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Tytuł:
Escherichia Coli w produktach mleczarskich
Escherichia Coli in dairy products
Autorzy:
Garbowska, M.
Berthold-Pluta, A.
Powiązania:
https://bibliotekanauki.pl/articles/228132.pdf
Data publikacji:
2013
Wydawca:
Wyższa Szkoła Menedżerska w Warszawie
Tematy:
Escherichia coli
chorobotwórczość
zatrucie pokarmowe
STEC
EHEC
O157:H7
pathogenesis
foodborne infection
Opis:
Gatunek Escherichia coli przyjęto za wskaźnik zanieczyszczenia fekalnego produktów spożywczych ze względu na występowanie tych drobnoustrojów w przewodzie pokarmowym i odchodach zwierząt stałocieplnych. Niektóre szczepy E. coli uznano za chorobotwórcze, gdyż wywołują szereg różnych chorób, począwszy od łagodnych biegunek, przez zapalenie jelit do poważnych chorób nerek. Szczepy chorobotwórczego serotypu E. coli O157 izolowano z odchodów zdrowych sztuk bydła, dlatego też sery produkowane z mleka niepasteryzowanego są potencjalnymi nośnikami tych drobnoustrojów. W pracy scharakteryzowano gatunek Escherichia coli, ze szczególnym uwzględnieniem serotypów chorobotwórczych w tym serotypu O157:H7. Dokonano przeglądu piśmiennictwa dotyczącego występowania chorobotwórczych szczepów Escherichia coli w mleku surowym oraz produktach mlecznych w różnych krajach oraz w Polsce. Przedstawiono wybrane przykłady występowania szczepów chorobotwórczych w mleku surowym i produktach mlecznych, przypadki zatruć wywołanych spożyciem produktów mlecznych zanieczyszczonych tymi serotypami.
Escherichia coli was accepted as a faecal contamination indicator of food products because of its presence in the intestinal system and faeces of warm blooded organisms. Several E. coli strains represent pathogens with wide spectrum of illness which may ensue ranging from mild diarrhoea through colitis to severe urinary diseases. Because pathogenic E. coli O157 serotypes have been found from healthy cattle faeces, cheeses made from unpasteurized milk are potential vehicle of this microorganisms. The study characterized the specium Escherichia coli, with particular emphasis on pathogenic serotypes, including serotype O157: H7. Has reviewed the literature regarding the occurrence of pathogenic strains of Escherichia coli in raw milk and dairy products in different countries and Poland. The paper has presented selected examples of occurrence pathogenic strains in raw milk and dairy products, incidents of foodborne infections caused by the consumption of dairy products contaminated by these serotypes.
Źródło:
Postępy Techniki Przetwórstwa Spożywczego; 2013, 1; 106-111
0867-793X
2719-3691
Pojawia się w:
Postępy Techniki Przetwórstwa Spożywczego
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Escherichia coli in sewage sludge - detection method
Escherichia coli w osadach ściekowych - metoda wykrywania
Autorzy:
Machnicka, A.
Powiązania:
https://bibliotekanauki.pl/articles/106338.pdf
Data publikacji:
2014
Wydawca:
Towarzystwo Chemii i Inżynierii Ekologicznej
Tematy:
E.coli
sewage sludge
enrichment of Escherichia coli
detection of Escherichia coli
E. coli
osady ściekowe
namnażanie Escherichia coli
wykrywanie Escherichia coli
Opis:
Escherichia coli is Gram-negative optionally anaerobic roads which belongs to Enterobacteriaceae family. Includes in a physiological bacterial flora of human and warm-blooded animals large intestine. Escherichia coli is being met in abiotic elements of the environment so as waters, wastewater, sewage sludge, soil and the food. This bacterium is showing the pathogenicity in named terms for the peoples, triggering diseases mainly: gastrointestinal tract and urinary. Quality and quantitative proposed detections method of the bacteria E. coli contains five/six steps: - appointment dry suspended solid, - preparation averaged, test of sample and resuscitation of bacteria, - making dilutions, - enrichment and differentiation in chromogenic-selective medium, - enumerating the amount of cfu E. coli in 1 g of a dry weight, - optionally, the biochemical identification.
Escherichia coli jest Gram-negatywną, względnie beztlenową pałeczką należącą do rodziny Enterobacteriaceae. Wchodzi w skład fizjologicznej flory bakteryjnej jelita grubego człowieka oraz zwierząt stałocieplnych. Spotyka się ją w elementach abiotycznych środowiska, takich jak wody, ścieki, osady ściekowe, gleba i żywność. Bakteria ta w określonych warunkach wykazuje chorobotwórczość dla człowieka, wywołując głównie schorzenia układów pokarmowego i moczowego. Proponowana metoda jakościowa i ilościowa wykrywania bakterii E. coli zawiera pięć/sześć etapów: - oznaczenie suchej masy osadu, - przygotowanie próbki uśrednionej i badawczej oraz przywrócenie bakteriom aktywności fizjologicznej, - wykonanie rozcieńczeń, - namnażanie i identyfikacja na podłożu chromogennym-selektywnym, - wyliczenie ilości jtk E. coli w 1 g suchej masy osadu, - opcjonalnie identyfikacja biochemiczna.
Źródło:
Chemistry-Didactics-Ecology-Metrology; 2014, 19, 1-2; 79-85
2084-4506
Pojawia się w:
Chemistry-Didactics-Ecology-Metrology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Środowisko a antybiotykooporność izolatów Escherichia coli
Envirnomental dissemision of resistance among Escherichia coli isolates
Autorzy:
Krzyśko-Łupicka, T.
Kręcidło, M.
Mysłek, M.
Kręcidło, Ł.
Powiązania:
https://bibliotekanauki.pl/articles/126404.pdf
Data publikacji:
2017
Wydawca:
Towarzystwo Chemii i Inżynierii Ekologicznej
Tematy:
metoda Kirby-Bauera
testowanie antybiotykoodporności
Escherichia coli
Kirby-Bauera method
antibiotic susceptibility testing
Opis:
Pula farmaceutyków w środowisku powiększa się w wyniku kontaminacji wód, gruntów, ścieków, a także surowców pochodzenia zwierzęcego. Obecność antybiotyków w środowisku wpływa nie tylko na zahamowanie rozwoju mikroorganizmów, ale w stężeniu subinhibicyjnym może stymulować ekspresję genów wywołujących zjawisko antybiotykooporności. Celem pracy było porównanie wrażliwości na antybiotyki pałeczek Escherichia coli wyizolowanych z surowego mleka i zmieszanych odpadów drobiarskich. Materiał badawczy stanowiły szczepy E.coli wyizolowane z surowca mleczarskiego i zmieszanych odpadów drobiarskich. Ocenę wrażliwości izolatów na antybiotyki przeprowadzono metodą Kirby-Bauera. Profil oporności E. coli ustalano na podstawie rekomendacji CLSI. Wykorzystano krążki firmy BTL wysycone takimi antybiotykami, jak: ampicylina (AM10), chloramfenikol (C30), gentamycyna (CN10), tetracyklina (TE30) oraz mieszaniną sulfmetoksazolu i trimetoprimu (SXT25). Izolaty E. coli z surowca mleczarskiego charakteryzowały się większą opornością na ampicylinę i wyższą wrażliwością na pozostałe badane antybiotyki w porównaniu do izolatów z odpadów drobiarskich.
Recently amount of pharmaceutical substances in the environment is getting higher due to spreading and relocation of water and soil contamination by sources such as a livestock production or sewage. The persistence of antibiotic in the environment may affect both the inhibition of microbial growth and also the stimulation of resistance gens expression, when antibiotics are in the subinhibitory concentration. The purpose of a study was to compare susceptibility of Escherichia coli isolates from two following sources: a raw milk from dairy and a poultry waste. The assessment of susceptibility on antibiotic was carried out by the Kirby-Bauer’s method. The resistance profile of isolates was estimated with using of CLSI standards. Antibiotic discs from BTL company were tested with particular type of substances: ampicillin (AM10), chloramphenicol (C30), gentamicin (CN10), tetracycline (TE30) and solution of sulfamethoxazole and trimethoprim (SXT25). Isolates of E. coli from raw milk were more resistant to ampicillin and characterised by higher susceptibility to the other antibiotics in the comparison to the isolates from poultry waste.
Źródło:
Proceedings of ECOpole; 2017, 11, 2; 517-523
1898-617X
2084-4557
Pojawia się w:
Proceedings of ECOpole
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Wpływ Escherichia coli na wzrost Bacillus cereus
The effect of Escherichia coli on growth of Bacillus cereus
Autorzy:
Stec, E.
Powiązania:
https://bibliotekanauki.pl/articles/874920.pdf
Data publikacji:
1991
Wydawca:
Narodowy Instytut Zdrowia Publicznego. Państwowy Zakład Higieny
Tematy:
produkty spozywcze
antagonizm bakteryjny
drobnoustroje
Escherichia coli
Bacillus cereus
Źródło:
Roczniki Państwowego Zakładu Higieny; 1991, 42, 1
0035-7715
Pojawia się w:
Roczniki Państwowego Zakładu Higieny
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Synergistic antibacterial effect of phenolic acids against Escherichia coli
Synergistyczne działanie przeciwbakteryjne kwasów fenolowych przeciwko Escherichia coli
Autorzy:
Synowiec, A.
Żyła, K.
Gniewosz, M.
Powiązania:
https://bibliotekanauki.pl/articles/13925559.pdf
Data publikacji:
2019
Wydawca:
Szkoła Główna Gospodarstwa Wiejskiego w Warszawie. Wydawnictwo Szkoły Głównej Gospodarstwa Wiejskiego w Warszawie
Tematy:
synergy
antibacterial effect
phenolic acid
Escherichia coli
biofilm
Źródło:
Zeszyty Problemowe Postępów Nauk Rolniczych; 2019, 598; 51-62
0084-5477
Pojawia się w:
Zeszyty Problemowe Postępów Nauk Rolniczych
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Genetic similarities of Escherichia coli isolated from hospitalized patients
Autorzy:
Żórawski, M.J.
Dudzik, D.
Musiałowska, D.
Powiązania:
https://bibliotekanauki.pl/articles/1918517.pdf
Data publikacji:
2017
Wydawca:
Uniwersytet Medyczny w Białymstoku
Tematy:
Escherichia coli
ADSRRSA
Opis:
Introduction: Escherichia coli is a component of human physiological flora. Pathogenic E. coli strains are a significant etiologic factor for numerous infections, mainly the urinary system, digestive system, respiratory system as well as bacteraemia and post-operative infections. Purpose: To compare the genetic similarity of Escherichia coli strains, isolated from biological material collected for routine microbiological diagnostics. Materials and methods: The examination performed on the Escherichia coli strains, isolated from material collected from patients hospitalized in various clinics and delivered for routine laboratory diagnostics. The analysis was conducted using the ADRSSR method.Results: As a result of the analysis of genetic similarities of examined strains using the ADRSSR method, nine clones were distinguished, clones A and B considered being most numerous. Clone A was predominant in samples from internal diseases clinics while cloning B – from neonatological clinics. Conclusions: The results point to a significant role of monitoring of homogeneity of bacteria strains isolated in the range of the health care providers. It is directly connected with the safety of hospitalized patients as well as effectiveness and course of the treatment. The use of the ADSRRS method gives the opportunity of early detection of the moment of colonization in the monitored place
Źródło:
Progress in Health Sciences; 2017, 7(1); 145-150
2083-1617
Pojawia się w:
Progress in Health Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Removal of Escherichia coli from Domestic Wastewater Using Electrocoagulation
Autorzy:
Aguilar-Ascon, Edwar
Powiązania:
https://bibliotekanauki.pl/articles/124695.pdf
Data publikacji:
2019
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
domestic wastewater
electrocoagulation
escherichia coli
electrochemical disinfection
Opis:
The objective of this study was to evaluate the efficiency of electrocoagulation in the removal of Escherichia coli from domestic and urban wastewaters and to determine the effects of the main operational parameters on the process. An electrocoagulation reactor with aluminum and iron electrodes was built for this purpose. A factorial design was applied, where amperage, treatment time, and pH were considered as the factors and E. coli percent removal was the response variable. After 20 min of treatment, >97% removal efficiency was achieved. The highest E. coli removal efficiency achieved was 99.9% at a neutral pH of 7, amperage of 3 A, and treatment time of 60 min. However, the removal efficiency of close to 99% was also achieved at natural wastewater pH of 8.5. The statistical analyses showed that the three tested factors significantly affected the E. coli removal percentage (p < 0.05). These results indicate that electrocoagulation has a high disinfection power in a primary reactor in removing water contaminants as well as simultaneously removing pathogenic microorganisms when compared to biological treatment processes. This represents an additional benefit, because it will considerably reduce the use of chlorine during the final disinfection stage.
Źródło:
Journal of Ecological Engineering; 2019, 20, 5; 42-51
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Escherichia coli as a potential indicator of Biebrza River enrichment sources
Escherichia coli jako potencjalny wskaźnik wzbogacania wód rzeki Biebrzy
Autorzy:
Frąk, M.
Powiązania:
https://bibliotekanauki.pl/articles/292919.pdf
Data publikacji:
2013
Wydawca:
Instytut Technologiczno-Przyrodniczy
Tematy:
Escherichia coli
indicator
water quality
sources of contamination
wskaźnik
jakość wody
źródła zanieczyszczeń
Opis:
The number of Escherichia coli cells in the waters of the Biebrza River was analyzed. The results were compared with the values of select chemical water quality indicators and with the Biebrza River catchment development. Organic contamination was detected along the entire run of the River and was caused by the presence of substances washed off the adjacent marshy areas and the influx of household and agricultural wastewaters. The highest number of bacteria was found in the Middle and Lower Basins of the Biebrza River. The incease in the number of E. coli in the spring to over 24 MPN·cm–3 is a result of the numerous presence of water birds in the area of the National Park. Of consequence are also meltwaters that introduce contamination from peat lands into the watercourse. The increased number of E. coli cells in the summer is related to runoff from the areas along the River with numerous farms and dairy cattle pastures. The number of bacteria in the river is most probably influenced by changes in water levels and types of accumulated sediment. The Escherichia coli count allows determining the source of the contamination of surface waters, which is of particular significance for planned water management on protected areas. The number of E. coli below 7 MPN·cm–3 in the waters of the Biebrza River is at the natural background level, whereas counts of over 24 MPN·cm–3 are related to the influx of household wastewaters.
W wodzie rzeki Biebrza analizowano liczebność Escherichia coli. Wyniki zestawiono z poziomem wybranych wskaźników jakości chemicznej wody oraz danymi, dotyczącymi zagospodarowania zlewni. Stwierdzono zanieczyszczenie organiczne na całej długości biegu rzeki, wywołane obecnością substancji wymywanych z okolicznych terenów bagiennych oraz dopływem ścieków bytowych i rolniczych. Największą liczebność bakterii stwierdzono w środkowym i dolnym basenie rzeki Biebrzy. W okresie wiosennym wzrost liczebności E. coli do ponad 24 NPL·cm–3 wynika z licznego występowania ptactwa wodnego na obszarze Parku Narodowego. Wpływ mają też wody roztopowe wnoszące do cieku zanieczyszczenia z terenów torfowych. Latem wzrost liczebności E. coli związany jest ze spływem z sąsiadujących z rzeką terenów, na których są gospodarstwa i pastwiska bydła mlecznego. Na liczebność bakterii w wodzie mają także prawdopodobnie wpływ zmiany poziomu wód, uruchamiające zasoby osadów dennych. Dzięki określeniu liczebności Escherichia coli można określić źródła zanieczyszczenia wód powierzchniowych, co jest szczególnie istotne dla planowej gospodarki wodnej na obszarach chronionych. Liczebność E. coli w wodach Biebrzy poniżej 7 MPN·cm–3 jest naturalnym poziomem, natomiast ponad 24 MPN·cm–3 wskazuje na napływ ścieków bytowych.
Źródło:
Journal of Water and Land Development; 2013, no. 19 [VII-XII]; 31-37
1429-7426
2083-4535
Pojawia się w:
Journal of Water and Land Development
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Mutator specificity of Escherichia coli alkB117 allele
Autorzy:
Nieminuszczy, Jadwiga
Janion, Celina
Grzesiuk, Elżbieta
Powiązania:
https://bibliotekanauki.pl/articles/1041261.pdf
Data publikacji:
2006
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
lacZ → Lac+ reversion
mutational specificity
E. coli
MMS
alkB117
Opis:
The Escherichia coli AlkB protein encoded by alkB gene was recently found to repair cytotoxic DNA lesions 1-methyladenine (1-meA) and 3-methylcytosine (3-meC) by using a novel iron-catalysed oxidative demethylation mechanism that protects the cell from the toxic effects of methylating agents. Mutation in alkB results in increased sensitivity to MMS and elevated level of MMS-induced mutations. The aim of this study was to analyse the mutational specificity of alkB117 in a system developed by J.H. Miller involving two sets of E. coli lacZ mutants, CC101-106 allowing the identification of base pair substitutions, and CC107-CC111 indicating frameshift mutations. Of the six possible base substitutions, the presence of alkB117 allele led to an increased level of GC→AT transitions and GC→TA and AT→TA transversions. After MMS treatment the level of GC→AT transitions increased the most, 22-fold. Among frameshift mutations, the most numerous were -2CG, -1G, and -1A deletions and +1G insertion. MMS treatment appreciably increased all of the above types of frameshifts, with additional appearance of the +1A insertion.
Źródło:
Acta Biochimica Polonica; 2006, 53, 2; 425-428
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The occurence of plasmid DNA in natural population of animal strains of Escherichia coli
Występowanie DNA plazmidowego w naturalnej populacji odzwierzęcych szczepów Escherichia coli
Vystuplenie plazmidnojj DNK v naturalnojj populjacii linijj Escherichia coli, proiskhodjashhikh ot zhivotnykh
Autorzy:
Kolodynski, J.
Franiczek, R.
Powiązania:
https://bibliotekanauki.pl/articles/68766.pdf
Data publikacji:
1991
Wydawca:
Polska Akademia Nauk. Instytut Genetyki Roślin PAN
Źródło:
Genetica Polonica; 1991, 32, 1-2
0016-6715
Pojawia się w:
Genetica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Wrażliwość na olejki eteryczne środowiskowych lekoopornych szczepów Escherichia coli
Sensitivity to the essential oils of environmental, resistant to drugs strains of Escherichia coli
Autorzy:
Krzyśko-Łupicka, T.
Mysłek, M.
Błaszczyk, K.
Powiązania:
https://bibliotekanauki.pl/articles/126593.pdf
Data publikacji:
2015
Wydawca:
Towarzystwo Chemii i Inżynierii Ekologicznej
Tematy:
Escherichia coli
antybiotykooporność
olejki eteryczne
antibiotic resistance
essential oils
Opis:
W środowisku coraz powszechnej stwierdzana jest obecność lekoopornych szczepów Escherichia coli. Alternatywną drogę ich eliminacji mogą stanowić biodegradowalne i nietoksyczne substancje, między innymi olejki eteryczne. Celem pracy była ocena działania olejków eterycznych na środowiskowe lekooporne szczepy Escherichia coli. Materiał badawczy stanowiło 10 wyizolowanych ze środowiska naturalnego lekooopornych szczepów E. coli, w tym 8 glukuronidazo-dodatnich. Wrażliwość szczepów na takie antybiotyki, jak: ampicylina, amoksycylina, cefotaksym, chloramfenikol, cyprofloksacyna, ceftazydym, doksycyklina, gentamycyna, kanamycyna, trimetoprim, tetracyklina, streptomycyna, kwas nalidyksowy oraz na sulfonamidy, oznaczono na podłożu Mueller-Hinton. Metodą dyfuzyjną płytkowo-cylinderkową oceniono wrażliwość szczepów na olejki: tymiankowy, oregano, herbaciany, lemongrasowy, cytrynowy i kminkowy oraz tymol w stężeniach 1,5%; 1,0%; 0,5%; 0,25%. Na podstawie uzyskanych wyników stwierdzono, że testowane szczepy E. coli wykazywały oporność na co najmniej połowę testowanych antybiotyków, a 90% z nich było oporne na ampicylinę i amoksycylinę. Także wrażliwość szczepów na testowane olejki eteryczne była zróżnicowana. Tylko olejek tymiankowy w stężeniach 1 i 1,5% zahamował rozwój 90% badanych szczepów E. coli. Olejki herbaciany, lemongrasowy, cytrynowy, oregano i kminkowy w testowanych stężeniach nie hamowały rozwoju testowanych szczepów Escherichia coli.
In an environment increasingly common finding is the presence of antibiotic-resistant strains of Escherichia coli. An alternative way to eliminate them can provide biodegradable and non-toxic substances, including essential oils. The aim of this study was to evaluate the effect of essential oils on environmental, antibiotic-resistant strains of Escherichia coli. The research material consisted of 10 isolated from the environment, antibiotic-resistant strains of E. coli, including 8 glucuronidase-positive. Using the Mueller-Hinton medium was evaluated the sensitivity to antibiotics such as ampicillin, amoxicillin, cefotaxime, chloramphenicol, ciprofloxacin, ceftazidime, doxycycline, gentamycin, kanamycin, trimethoprim, tetracycline, streptomycin, nalidixic acid and sulfonamides. Using the platelet-cylinders diffusion method was assessed the sensitivity of the strains on essential oils: thyme, oregano, tea tree, lemongrass, lemon, and caraway, at concentrations of 1.5%; 1.0%; 0.5%, 0.25%. Based on the results, it was found that the tested strains of E. coli were resistant to at least half of the used antibiotics and 90% of them showed resistance to ampicillin, and amoxicillin. Also, the sensitivity of the strains to tested essential oils has been diverse. Only thyme oil in a concentration of 1.5% inhibited growth of 90% of the tested strains of E. coli. On the other hand, oregano oil in a concentration of 1.5% inhibited the development of 3 out of 10 tested strains. Oils of tea, lemongrass, lemon and caraway, at the mentioned concentrations have been not bactericidal against strains of Escherichia coli.
Źródło:
Proceedings of ECOpole; 2015, 9, 2; 633-639
1898-617X
2084-4557
Pojawia się w:
Proceedings of ECOpole
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Ekspresja genów klonowanych w wektorach plazmidowych w zrekombinowanych szczepach Escherichia Coli
Expression of genes cloned in plasmid vectors in recombinant Escherichia Coli strains
Autorzy:
Sęktas, Marian
Powiązania:
https://bibliotekanauki.pl/articles/1201663.pdf
Data publikacji:
2002
Wydawca:
Polskie Towarzystwo Przyrodników im. Kopernika
Opis:
Use of Escherichia coli bacteria as a host for high-level expression of cloned genes has become common. The purification of a recombinant protein is greatly accelerated if the protein can be isolated from cells that overproduce it. To maximize expression, the cloned gene must be transcribed and translated as efficiently as possible. This is possible due to the construction of expression vectors, modified plasmids with useful features, which can be propagated and controlled in special hosts (expression systems). Usually, vectors for cloning and expressing target DNA are derived from medium-copy plasmids like pBR322. E. coli expression systems should meet several criteria including (i) minimal basal expression of the gene to be expressed under repressed conditions, (ii) fast and uncomplicated induction of a wide variety of genes to a high level of expression, and, (iii) easy cloning and DNA manipulation features. This article describes how the most common T7 expression system, derived from bacteriophage T7, functions. The system consists of a plasmid vector that allows cloning of the target DNA under T7 promoter control, and the T7 RNA polymerase gene borne by the recombinant bacterial host. The system is capable of expressing a wide variety of DNAs from prokaryotic and eukaryotic sources. In principle, the T7 system can be completely selective because host RNA polymerase and phage's polymerase recognize different promoters. However, synthesis of recombinant proteins, especially those that are toxic to the host, must be controlled, being at zero or non-toxic levels in uninduced cells, and high only after induction of expression during the appropriate phase of growth. Basal activity of the T7 RNA polymerase in uninduced cells is lower when the growth medium contains glucose (catobolite repression) and/or its natural inhibitor T7 lysozyme. Another way to reduce the basal expression of the target genes is to use expression vectors with lower or controllable copy numbers. The last possibility is offered by a new single-conditional-medium copy vector, a derivative of two replicons with different functions, oriS/RepE from plasmid F and oriV/TrfA from RK2 plasmid. The genetic elements from F plasmid enable stable maintenance of a single copy of the plasmid, while the RK2 replicon permits dosage-dependent gene expression and serves as the means for plasmid DNA amplification.
Źródło:
Kosmos; 2002, 51, 3; 365-373
0023-4249
Pojawia się w:
Kosmos
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Virulence and antibiotic resistance of Escherichia coli isolated from rooks
Autorzy:
Kmet, V.
Drugdova, Z.
Kmetova, M.
Stanko, M.
Powiązania:
https://bibliotekanauki.pl/articles/51141.pdf
Data publikacji:
2013
Wydawca:
Instytut Medycyny Wsi
Tematy:
virulence
antibiotic resistance
Escherichia coli
isolation
rook
polymerase chain reaction
DNA microarray
Opis:
With regard to antibiotic resistance studies in various model animals in the urban environment, the presented study focused on the rook, many behavioural and ecological aspects of which are important from an epidemiological point of view. A total of 130 Escherichia coli strains isolated from rook faeces during a two-year period (2011–2012) were investigated for antibiotic resistance and virulence. Resistance to ampicillin (60%) and streptomycin (40%) were the most frequent, followed by resistance to fluoroquinolones (ciprofloxacin-22% and enrofloxacin-24%), tetracycline (18%), cotrimoxazol (17%) and florfenicol (14%). Ceftiofur resistance occured in 10.7 % of strains and cefquinom resistance in 1.5 % of strains. Twenty-five E.coli strains with a higher level of MICs of cephalosporins (over 2mg/L of ceftazidime and ceftriaxon) and fluoroquinolones were selected for detection of betalactamase genes (CTX-M, CMY), plasmid-mediated quinolone resistance qnrS, integrase 1, and for APEC (avian pathogenic E.coli) virulence factors (iutA, cvaC, iss, tsh, ibeA, papC, kpsII). Genes of CTX-M1, CMY-2, integrase 1, papC, cvaC, iutA were detected in one strain of E.coli, and qnrS, integrase 1, iss, cvaC, tsh were detected in another E.coli. DNA microarray revealed the absence of verotoxin and enterotoxin genes and pathogenicity islands. The results show that rooks can serve as a reservoir of antibiotic-resistant E. coli with avian pathogenic virulence factors for the human population, and potentially transmit such E.coli over long distances.
Źródło:
Annals of Agricultural and Environmental Medicine; 2013, 20, 2
1232-1966
Pojawia się w:
Annals of Agricultural and Environmental Medicine
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Extended spectrum beta-lactamases in Escherichia coli from municipal wastewater
Autorzy:
Cornejova, T.
Venglovsky, J.
Gregova, G.
Kmetova, M.
Kmet, V.
Powiązania:
https://bibliotekanauki.pl/articles/50050.pdf
Data publikacji:
2015
Wydawca:
Instytut Medycyny Wsi
Źródło:
Annals of Agricultural and Environmental Medicine; 2015, 22, 3
1232-1966
Pojawia się w:
Annals of Agricultural and Environmental Medicine
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Antibiotic resistance of Escherichia coli isolated from a poultry slaughterhouse
Autorzy:
Gregova, G.
Kmetova, M.
Kmet, V.
Venglovsky, J.
Feher, A.
Powiązania:
https://bibliotekanauki.pl/articles/52172.pdf
Data publikacji:
2012
Wydawca:
Instytut Medycyny Wsi
Opis:
The aim of the study was to investigate the antibiotic resistant E. coli strains isolated from bioaerosols and surface swabs in a slaughterhouse as a possible source of poultry meat contamination. The highest air coliforms contamination was during shackling, killing and evisceration of poultry. The strains showed resistance to ampicillin (89%), ceftiofur (62%) and cefquinome (22%), while resistance to ampicillin with sulbactam was only 6%. Resistance to streptomycin and gentamicin was detected in 43% vs. 14% isolates; to tetracycline 33%; to chloramphenicol and florfenicol in 10% vs. 18% isolates; to cotrimoxazol in 35% isolates; to enrofloxacin in 43 % isolates. The higher MIC of ceftazidime (3.6 mg.l-1) and ceftriaxon (5.2 mg.l-1) revealed the presence of ESBLs in 43% of isolates. From 19 selected phenotypically ESBL positive strains, 16 consisted of CMY-2 genes, while CTX-M genes were not detected by PCR. Maldi tof analysis of selected E. coli showed a clear clonal relatedness of environmental strains from various withdrawals.
Źródło:
Annals of Agricultural and Environmental Medicine; 2012, 19, 1
1232-1966
Pojawia się w:
Annals of Agricultural and Environmental Medicine
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Antibacterial activity of Tribulus terrestris methanol extract against clinical isolates of Escherichia coli
Działanie antybakteryjne wyciągu etanolowego z Tribulus terrestris na kliniczne izolaty Escherichia coli
Autorzy:
Batoei, S.
Mahboubi, M.
Yari, R.
Powiązania:
https://bibliotekanauki.pl/articles/72055.pdf
Data publikacji:
2016
Wydawca:
Instytut Włókien Naturalnych i Roślin Zielarskich
Opis:
Introduction: Tribulus terrestris L. is traditionally used for treatment of urinary tract infections. Escherichia coli, as the most prominent agent of urinary tract infections, can be sensitive to T. terrestris extract. Objectives: The aim of this study was to evaluate the antibacterial activity of T. terrestris methanol extract against clinical isolates of E. coli from urinary tract infections. Saponins were determined as main constituents of T. terrestris methanol extract. Methods: The antibacterial activities of T. terrestris methanol extract were evaluated by micro-broth dilution assay. The synergistic effects of T. terrestris methanol extract were screened with gentamicin by micro titer plate and disc diffusion assays. The isobologram curve was figured and the Fractional Inhibitory Concentration Index (FICI) was determined. Results: The saponin content of T. terrestris methanol extract was 54% (w/w). The means of MIC and MBC values for E. coli clinical isolates (n=51) were 3.5±0.27 and 7.4±0.5 mg/ml while these amounts were 3.9±1.3 and 6.4±1.8 μg/ml for gentamicin. T. terrestris methanol extract and gentamicin had synergistic effect with FICI equal to 0.1375. Conclusion: Therefore, T. terrestris can be applicable as alternative treatment in management of urinary tract infections.
Wstęp: Tribulus terrestris L. jest tradycyjnie stosowany w leczeniu zakażeń układu moczowego. Escherichia coli, jako główny czynnik zakażeń tego układu, może wykazywać wrażliwość na działanie ekstraktu z T. terrestris.Cel: Celem badań było określenie aktywności przeciwbakteryjnej ekstraktu metanolowego uzyskanego z ziela T. terrestris w stosunku do szczepów E. coli izolowanych od osób z zakażeniami układu moczowego. Metody: Działanie przeciwbakteryjne ekstraktu metanolowego z T. terrestris określano metodą rozcieńczeń w pożywce płynnej. Działanie synergistyczne ekstraktu metanolowego z T. terrestris z gentamycyną badano metodą krążków bibułowych w podłożu agarowym. Na tej podstawie wyznaczono krzywą izobolograficzną oraz ułamkowe stężenie hamujace dla obu substancji (Fractional Inhibitory Concentration Index – FICI). Wyniki: Zawartość saponin w ekstrakcie metanolowym z T. terrestris wynosiła 54% (w/w). Średnie wartości MIC i MBC dla szczepów klinicznych E. coli (n=51) wynosiły odpowiednio 3,5±0,27, 7,4±0,5 mg/ml, a dla gentamycyny odpowiednio 3,9±1,3 i 6,4±1,8 µg/ml. Ekstrakt metanolowy i gentamycyna wykazywały działanie synergistyczne na poziomie FICI równego 0,1375. Wniosek: Wykazano, że ekstrakt metanolowy z ziela T. terrestris, może być stosowany jako alternatywny środek do leczenia zakażeń układu moczowego.
Źródło:
Herba Polonica; 2016, 62, 2
0018-0599
Pojawia się w:
Herba Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Selective depression of Escherichia coli on flotation of collophanite and dolomite
Autorzy:
Li, JiaXin
Nie, GuangHua
Jiang, Ying
Luo, GuoJv
Li, Jie
Powiązania:
https://bibliotekanauki.pl/articles/2146918.pdf
Data publikacji:
2022
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
Escherichia coli
collophanite
dolomite
flotation
phosphate rock
Opis:
The phosphate rock flotatio n test was carried out using Escherichia coli E. coli ) as a depressant of dolomite. The results showed that E. coli had a great selective depression on dolomite during flotation. With E. coli as a depressant of dolomite, a useful beneficiation index of phosphorus concentrate with P2O5 grade of more than 30% and MgO content less than 1.2% can be obtained by closed circuit of one stage roughing and one stage cleaning. Furthermore, the depression mechanism of E. coli was studied by ad sorption experiments, infrared spectrum, and zeta potential. This study shows that the adsorption ability of E. coli onto dolomite is stronger than that of collophanite. When the pH is greater than 6, E. coli are chemically adsorbed on the surface of the c ollophanite and dolomite,which also increases the negative charge on the surface of the two minerals. The selective adsorption of E. coli cells to dolomite was best when the pH value is about 7.8.
Źródło:
Physicochemical Problems of Mineral Processing; 2022, 58, 4; art. no. 150604
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Antibiotic resistance and siderophores production by clinical Escherichia coli strains
Autorzy:
Khazaal, Mohamed T.
El-Hendawy, Hoda H.
Mabrouk, Mona I.
Faraag, Ahmed H.I.
Bakkar, Marwa R.
Powiązania:
https://bibliotekanauki.pl/articles/16648088.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
siderophores
Escherichia coli
clinical strains
antibiotic susceptibility
Opis:
The phenomenon of antibiotic resistance has dramatically increased in the last few decades, especially in enterobacterial pathogens. Different strains of Escherichia coli have been reported to produce a variety of structurally different siderophores. In the present study, 32 E. coli strains were collected from different clinical settings in Cairo, Egypt and subjected to the antibiotic susceptibility test by using 19 antibiotics belonging to 7 classes of chemical groups. The results indicated that 31 strains could be considered as extensively drug-resistant and only one strain as pan drug-resistant. Siderophores production by all the tested E. coli strains was determined qualitatively and quantitatively. Two E. coli strains coded 21 and 49 were found to be the most potent siderophores producers, with 79.9 and 46.62%, respectively. Bacterial colonies with cured plasmids derived from strain 49 showed susceptibility to all the tested antibiotics. Furthermore, E. coli DH5α cells transformed with the plasmid isolated from E. coli strain 21 or E. coli strain 49 were found to be susceptible to ansamycins, quinolones, and sulfonamide groups of antibiotics. In contrast, both plasmid-cured and plasmid-transformed strains did not produce siderophores, indicating that the genes responsible for siderophores production were located on plasmids and regulated by genes located on the chromosome. On the basis of the obtained results, it could be concluded that there is a positive correlation between antibiotic resistance, especially to quinolones and sulfonamide groups, and siderophores production by E. coli strains used in this study.
Źródło:
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology; 2022, 103, 2; 169-184
0860-7796
Pojawia się w:
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Determination of epoxides in Escherichia coli expressing recombinant zeaxanthin epoxidase
Autorzy:
Kuczynska, P.
Leskiewicz, S.
Strzalka, W.
Olchawa-Pajor, M.
Bojko, M.
Latowski, D.
Strzalka, K.
Powiązania:
https://bibliotekanauki.pl/articles/81277.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
conference
zeaxanthin epoxidase
overexpression
violaxanthin
antheraxanthin
Escherichia coli
spectrofluorometry
Źródło:
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology; 2013, 94, 3
0860-7796
Pojawia się w:
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Type 1 fimbriae in commensal Escherichia coli derived from healthy humans
Autorzy:
Pusz, Paweł
Bok, Ewa
Mazurek, Justyna
Stosik, Michał
Baldy-Chudzik, Katarzyna
Powiązania:
https://bibliotekanauki.pl/articles/1039310.pdf
Data publikacji:
2014
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
commensal E. coli
type 1 fimbriae
gene expression
Opis:
Type 1 fimbriae are one of the most important factors of Escherichia coli adaptation to different niches in the host. Our study indicated that the genetic marker - fimH gene occurred commonly in commensal E. coli derived from healthy humans but expression of the type 1 fimbriae was not observed. Identification of fim structural subunit genes (fimA-fimH) and recombinase fimE and fimB genes showed that many of the strains were carrying an incomplete set of genes and the genes expression study revealed that in strains with complete set of fim genes, the fimC gene, encoding the chaperone protein, was not expressed.
Źródło:
Acta Biochimica Polonica; 2014, 61, 2; 389-392
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Extra-intestinal pathogenic Escherichia coli – threat connected with food-borne infections
Autorzy:
Wasiński, B.
Powiązania:
https://bibliotekanauki.pl/articles/2085200.pdf
Data publikacji:
2019
Wydawca:
Instytut Medycyny Wsi
Tematy:
food
food-borne pathogens
extra-intestinal pathogenic escherichia coli
ExPEC
Opis:
Infections caused by extra-intestinal pathogenic Escherichia coli (ExPEC) are a serious public health problem worldwide. The most troublesome are urinary tract infections, severe neonatal meningitis, serious intraabdominal infections, and more rarely, pneumonia, intravascular-device infections, osteomyelitis, soft-tissue infections or sometimes bacteraemia. These strains are also able cause significant economic losses in animal husbandry. A thorough understanding of ExPEC ecology, reservoirs, chains and dynamics of transmission can greatly contribute to a reduction in the burden of ExPEC-associated disease. The ability of E. coli (including ExPEC) to exist and survive in various ecological niches impedes the precise recognition and indication of transmission routes most important for individual infections cases. Among many identified ExPEC reservoirs, animal companion and animals providing food seem to be important sources of infection for human; however, the real level of risk connected with potential transmission of these bacteria remains unclear. Food is indicated as one of potential ways of transmission. Despite a quite high number of reports, many of the uncertainties are expected to be reliably elucidated. This review presents most important data on the current state of knowledge concerning the potential role of food in ExPEC transmission. The possible consequences of ExPEC infections in human and animals are briefly described.
Źródło:
Annals of Agricultural and Environmental Medicine; 2019, 26, 4; 532-537
1232-1966
Pojawia się w:
Annals of Agricultural and Environmental Medicine
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis of uropathogenic Escherichia coli biofilm formation under different growth conditions
Autorzy:
Adamus-Białek, Wioletta
Kubiak, Anna
Czerwonka, Grzegorz
Powiązania:
https://bibliotekanauki.pl/articles/1038911.pdf
Data publikacji:
2015
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
biofilm
uropathogenic Escherichia coli
urinary tract infections
Opis:
The ability to form different types of biofilm enables bacteria to survive in a harsh or toxic environment. Different structures of biofilms are related to different surfaces and environment of bacterial growth. The aim of this study was analysis of the biofilm formation of 115 clinical uropathogenic Escherichia coli strains under different growth conditions: surface for biofilm formation, medium composition and time of incubation. The biofilm formation after 24 h, 48 h, 72 h and 96 h was determined spectrophotometrically (A531) after crystal violet staining and it was correlated with bacterial growth (A600). The live and dead cells in biofilm structures was also observed on the glass surface by an epi-fluorescence microscope. Additionally, the presence of rpoS, sdiA and rscA genes was analyzed. The statistical significance was estimated by paired T-test. The observed biofilms were different for each particular strain. The biofilm formation was the highest in the rich medium (LB) after 24 h and its level hasn't changed in time. When biofilm level was compared to bacterial growth (relative biofilm) - it was higher in a minimal medium in comparison to enriched medium. These results suggest that most of the bacterial cells prefer to live in a biofilm community under the difficult environmental conditions. Moreover, biofilm formation on polyurethane surface did not correlate with biofilm formation on glass. It suggests that mechanisms of biofilm formation can be correlated with other bacterial properties. This phenomenon may explain different types of biofilm formation among one species and even one pathotype - uropathogenic Escherichia coli.
Źródło:
Acta Biochimica Polonica; 2015, 62, 4; 765-771
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Properties of recombinant trehalose synthase from Deinococcus radiodurans expressed in Escherichia coli
Autorzy:
Filipkowski, Paweł
Pietrow, Olga
Panek, Anna
Synowiecki, Józef
Powiązania:
https://bibliotekanauki.pl/articles/1039724.pdf
Data publikacji:
2012
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
trehalose
trehalose synthase
Escherichia coli
gene expression
Deinococcus radiodurans
Opis:
A trehalose synthase gene from Deinococcus radiodurans (DSMZ 20539) containing 1659 bp reading frame encoding 552 amino acids was amplified using PCR. The gene was finally ligated into pET30Ek/LIC vector and expressed after isopropyl β-d-thiogalactopyranoside induction in Escherichia coli (DE3) Rosetta pLysS. The recombinant trehalose synthase (DraTreS) containing a His6-tag at the C-terminus was purified by metal affinity chromatography and characterized. The expressed enzyme is a homodimer with molecular mass of 126.9 kDa and exhibits the highest activity of 11.35 U/mg at pH 7.6 and at 30°C. DraTreS activity was almost unchanged after 2 h preincubation at 45°C and pH 7.6, and retained about 56% of maximal value after 8 h incubation at 50°C. The DraTreS was strongly inhibited by Cu2+, Hg2+, Zn2+, Al3+ and 10 mM Tris. The Km value of maltose conversion was 290.7 mM.
Źródło:
Acta Biochimica Polonica; 2012, 59, 3; 425-431
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Escherichia coli strains from ostriches and their sensitivity to antimicrobial substances
Autorzy:
Scerbova, J.
Laukova, A.
Powiązania:
https://bibliotekanauki.pl/articles/31475.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Opis:
Ostriches are bred especially for their high-quality meat. There is a lack of knowledge concerning the ostrich’s microflora. Escherichia coli is a commensal microorganism of the poultry intestine, ostriches included. However, some strains may become pathogenic. This study was therefore undertaken to detect coliform bacteria in ostrich faeces and to test their antibiotic profile and sensitivity to enterocins. Faeces (n=54, 18 mixture samples from 3 different age groups of 140 ostriches) were sampled to isolate coliform bacteria. The counts of coliform bacteria varied from 5.69 ± 2.4 log10 CFU/g to 5.73 ± 2.4 CFU/g. Pure colonies were identified using MALDI-TOF MS mass spectrometry and confirmed by phenotypization. Seventy-one strains were allotted to the species E. coli. Sixty-four of those 71 strains caused hemolysis. They were mostly polyresistant to antibiotics. Thirty-two poly-resistant strains of E. coli were sensitive to enterocins. These strains were most sensitive to Ent 9296 (26 strains). Moreover, Ent EM41 produced by E. faecium EM41 (isolated from ostrich faeces) inhibited the growth of 20 strains, reaching activity of 100 AU/ml. Our results indicate the possibility of enterocins being used for prevention/reduction of coliforms. Of course, in vivo studies are also being processed.
Źródło:
Polish Journal of Veterinary Sciences; 2016, 19, 2
1505-1773
Pojawia się w:
Polish Journal of Veterinary Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Occurrence and Survivability of Escherichia coli and Enterococci in Waters Used as Bathing Areas
Występowanie i przeżywalność Escherichia coli i enterokoków w wodach wykorzystywanych jako kąpieliska
Autorzy:
Budzińska, K.
Szejniuk, B.
Michalska, M.
Berleć, K.
Powiązania:
https://bibliotekanauki.pl/articles/1813714.pdf
Data publikacji:
2018
Wydawca:
Politechnika Koszalińska. Wydawnictwo Uczelniane
Tematy:
bathing water
indicator bacteria
survivability
Escherichia coli
Enterococcus faecalis
woda kąpieliskowa
bakterie wskaźnikowe
przeżywalność
Opis:
Bathing waters during the holiday season are used with great frequency for recreational purposes. It should be noted that they are subject to microbiological contamination, and therefore pose a serious health risk to the people using them. In accordance with the above, study which was undertaken aimed at assessing the purity status of water used for bathing purposes and determining the survival time of Escherichia coli and Enterococcus faecalis bacteria in the test water. Water samples were taken from three bathing areas of the Koronowo Reservoir: Samociążek (batching area I), Pieczyska (bathing area II), Kręgiel (bathing area III) three times in the months of July, August and September. The number of indicator bacteria Escherichia coli and enterococci was determined in the water samples. Additionally, each time the samples were taken, the water temperature and the number of bathers were measured. The determination of the number of Escherichia coli and enterococci bacteria in the tested water samples was performed by membrane filtration. Two strains of Escherichia coli ATCC 25922 and Enterococcus faecalis ATCC 19433 were used in studies to determine the survival time. Changes in the number of indicator bacteria were determined by usage of MPN method (most probable number of bacteria). The analyzes indicated that the water tested was characterized by significant microbiological contamination, because in July the occurrence of E.coli bacteria was recorded at an average of 3697 cfu/100 ml (bathing area I) to 4539 cfu/100 ml (bathing area II). Additionally, in the samples of water taken from the bathing area III, the number of these bacteria was high and amounted to 3836 cfu/100 ml. However, in August the number of these bacteria decreased and ranged from 2062 cfu/100 ml (bathing area I) to 3327 cfu/100 ml (bathing area III). In the case of enterococci, it was found that the majority of these microorganisms were isolated from water from bathing area I in July and their number was 412 cfu/100 ml and from the bathing area III in August – 404 cfu/100 ml. In the remaining samples of the analyzed water, the number of enterococci didn’t exceed the normative value of 400 cfu/100 ml. It was indicated that in September the water from all the examined bathing areas met the microbiological requirements specified in the applicable legal acts. The obtained results proved that the number of indicator bacteria was determined by the temperature of water and the number of bathers. In accordance to regression equations, it was found that Escherichia coli and Enterococcus faecalis lasted longer in water at temperature of 4°C respectively: 45 and 52 days, while at temperature of 20°C their survival time was 52 and 26 days. The study indicated the necessity to perform permanent sanitary control of water used for bathing purposes in the aspect of epidemiological threats.
Wody kąpieliskowe w sezonie wakacyjnym wykorzystywane są z dużą częstotliwością w celach rekreacyjnych. Należy podkreślić, że ulegają one zanieczyszczeniu mikrobiologicznemu, w związku z czym stanowią poważne zagrożenie zdrowotne dla korzystających z nich osób. W związku z powyższym podjęto badania, których celem była ocena stanu czystości wody wykorzystywanej w celach kąpieliskowych oraz ustalenie w badanej wodzie czasu przeżywalności bakterii Escherichia coli i Enterococcus faecalis. Próbki wody pobierano z trzech kąpielisk Zalewu Koronowskiego: Samociążek (kąpielisko I), Pieczyska (kąpielisko II), Kręgiel (kąpielisko III) trzykrotnie w miesiącach lipcu, sierpniu oraz we wrześniu. W próbkach wody oznaczono liczbę bakterii wskaźnikowych Escherichia coli i enterokoków. Dodatkowo przy każdym poborze próbek dokonywano pomiaru temperatury wody oraz liczbę kąpiących się osób. Oznaczenie liczby bakterii Escherichia coli oraz enterokoków w badanych próbkach wody przeprowadzono metodą filtracji membranowej. W badaniach dotyczących ustalenia czasu przeżywalności wykorzystano dwa szczepy Escherichia coli ATCC 25922 oraz Enterococcus faecalis ATCC 19433. Zmiany liczebności bakterii wskaźnikowych oznaczono metodą NPL (najbardziej prawdopodobna liczba bakterii). Przeprowadzone analizy wykazały, że badana woda charakteryzowała się znacznym zanieczyszczeniem mikrobiologicznym, ponieważ w miesiącu lipcu odnotowano występowanie bakterii E. coli średnio na poziomie od 3697 cfu/100 ml (kąpielisko I) do 4539 cfu/100 ml (kąpielisko II). Ponadto w próbkach wody pobranych z kąpieliska III liczba tych bakterii była wysoka i wynosiła 3836 cfu/100 ml. Z kolei w sierpniu liczba tych bakterii zmniejszyła się i kształtowała się w zakresie od 2062 cfu/100 ml (kąpielisko I) do 3327 cfu/100 ml (kąpielisko III). W przypadku enterokoków stwierdzono, że najwięcej tych drobnoustrojów wyizolowano z próbek wody z kąpieliska I w lipcu, liczba ich wynosiła 412 cfu/100 ml oraz z III kąpieliska w miesiącu sierpniu – 404 cfu/100 ml. W pozostałych próbkach analizowanej wody liczba enterokoków nie przekroczyła wartości normatywnej 400 cfu/100 ml. Wykazano, że w miesiącu wrześniu woda ze wszystkich badanych kąpielisk spełniała wymagania mikrobiologiczne określone w obowiązujących aktach prawnych. Uzyskane wyniki dowiodły, że liczba bakterii wskaźnikowych determinowana była temperaturą wody i liczbą kąpiących się osób. Na podstawie równań regresji ustalono że bakterie Escherichia coli i Enterococcus faecalis dłużej przeżywały w wodzie o temperaturze 4°C odpowiednio: 45 i 52 dni, natomiast w temperaturze 20°C czas ich przetrwania wynosił 52 i 26 dni. Przeprowadzone badania wskazują na konieczność ciągłego monitoringu wody wykorzystywanej w celach kąpieliskowych w aspekcie zagrożeń epidemiologicznych.
Źródło:
Rocznik Ochrona Środowiska; 2018, Tom 20, cz. 1; 309-325
1506-218X
Pojawia się w:
Rocznik Ochrona Środowiska
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Role of rpoS in the regulation of glyoxalase III in Escherichia coli.
Autorzy:
Benov, Ludmil
Sequeira, Fatima
Beema, Anees
Powiązania:
https://bibliotekanauki.pl/articles/1041571.pdf
Data publikacji:
2004
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
methylglyoxal
stationary phase
glyoxalases
RpoS
Opis:
Methylglyoxal is an endogenous electrophile produced in Escherichia coli by the enzyme methylglyoxal synthase to limit the accumulation of phosphorylated sugars. In enteric bacteria methylglyoxal is detoxified by the glutathione-dependent glyoxalase I/II system, by glyoxalase III, and by aldehyde reductase and alcohol dehydrogenase. Here we demonstrate that glyoxalase III is a stationary-phase enzyme. Its activity reached a maximum at the entry into the stationary phase and remained high for at least 20 h. An rpoS- mutant displayed normal glyoxalase I and II activities but was unable to induce glyoxalase III in stationary phase. It thus appears that glyoxalase III is regulated by rpoS and might be important for survival of non-growing E. coli cultures.
Źródło:
Acta Biochimica Polonica; 2004, 51, 3; 857-860
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Monitoring of pharmaceutical residues of non-steroidal drugs with use of Escherichia coli-gfp biosensors
Monitorowanie pozostałości farmaceutycznych leków niesterydowych z zastosowaniem Escherichia coli-gfp biosensorów
Autorzy:
Matejczyk, M.
Rosochacki, S. J.
Jabłońska-Trypuć, A.
Powiązania:
https://bibliotekanauki.pl/articles/387762.pdf
Data publikacji:
2016
Wydawca:
Towarzystwo Chemii i Inżynierii Ekologicznej
Tematy:
environmental monitoring
non-steroidal anti-inflammatory drugs
cytotoxicity
genotoxicity
gfp biosensor
monitoring środowiskowy
niesterydowe przeciwzapalne leki
cytotoksyczność
genotoksyczność
Opis:
Escherichia coli strains containing a three different plasmid-borne transcriptional fusion between genotoxin-inducible recA, kat G and sodA promoters involved in the SOS regulon and bacteria stress response and mutated form of gfp reporter gene, have been used. GFP-based bacterial biosensors allowed for detection of a cytotoxic and genotoxic activity of ibuprofenum, ketoprofenum and paracetamolum – conventional non-steroidal anti-inflammatory drugs in PBS buffer and surface water. For experimental tests drugs were used at concentration of 10–6; 10–7; 10–8; 10–9 and 10–10 mg/dm3, with bacteria strains time incubation of 3 and 24 hours. Experimental data indicated, that three promoters fusions with gfp gene as reporter were differently sensitive to applied drugs. Bacteria strains, recA, kat G and sodA promoters were a good bioindicator for cytotoxic and genotoxic effect monitoring of tested drugs in PBS buffer and surface water. The results showed, that applied in this experiment E. coli gfp biosensors strains could be potentially useful for environmental monitoring of cytotoxic and genotoxic effect of pharmacist residues of drugs in surface water.
W pracy wykorzystano szczepy Escherichia coli zawierające plazmidowe, trzy różne konstrukty genowe indukowalnych genotoksynami promotorów recA, kat G i sodA pochodzących z regulonu SOS oraz szlaków bakteryjnej odpowiedzi stresowej w fuzji z genem reporterowym gfp. GFP-bakteryjny biosensor pozwolił na detekcję cyto- i genotoksycznej aktywności ibuprofenu, ketoprofenu i paracetamolu – konwencjonalnych niesterydowych leków przeciwzapalnych w buforze PBS oraz wodzie powierzchniowej. Leki stosowano w stężeniach 10–6; 10–7; 10–8; 10–9 and 10–10 mg/dm3, z czasem inkubacji bakterii 3 i 24 godziny. Wyniki eksperymentu wykazały zróżnicowaną wrażliwość trzech różnych konstrukcji genowych na badane leki. Szczepy bakterii oraz RecA, kat G i sodA promotory okazały się dobrymi bioindykatorami monitorowanego cyto- i genotoksycznego efektu testowanych leków w buforze PBS i wodzie powierzchniowej. Uzyskane rezultaty wskazują na potencjalną użyteczność stosowanych w pracy bakteryjnych biosensorów w monitorowaniu pozostałości farmaceutycznych leków w środowisku.
Źródło:
Ecological Chemistry and Engineering. A; 2016, 23, 1; 45-62
1898-6188
2084-4530
Pojawia się w:
Ecological Chemistry and Engineering. A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Characterization of disulfide exchange between DsbA and HtrA proteins from Escherichia coli
Autorzy:
Skórko-Glonek, Joanna
Sobiecka-Szkatuła, Anna
Lipińska, Barbara
Powiązania:
https://bibliotekanauki.pl/articles/1041221.pdf
Data publikacji:
2006
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
DsbA oxidoreductase
disulfide exchange
HtrA protease
stoichiometry of HtrA-DsbA interaction
kinetics of HtrA oxidation
Opis:
DsbA is the major oxidase responsible for generation of disulfide bonds in proteins of E. coli envelope. In the present work we provided the first detailed characterization of disulfide exchange between DsbA and its natural substrate, HtrA protease. We demonstrated that HtrA oxidation relies on DsbA, both in vivo and in vitro. We followed the disulfide exchange between these proteins spectrofluorimetrically and found that DsbA oxidizes HtrA with a 1 : 1 stoichiometry. The calculated second-order apparent rate constant (kapp) of this reaction was 3.3 × 104 ± 0.6 × 104 M-1s-1. This value was significantly higher than the values obtained for nonfunctional disulfide exchanges between DsbA and DsbC or DsbD and it was comparable to the kapp values calculated for in vitro oxidation of certain non-natural DsbA substrates of eukaryotic origin.
Źródło:
Acta Biochimica Polonica; 2006, 53, 3; 585-589
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Wpływ endotoksyny bakteryjnej z Escherichia coli na hematopoezę u myszy
Vlijanie bakterialnykh ehndotoksinov osvobozhdaemykh kishechnymi palochkami na krovetvorenie u myshejj
The effect of endotoxin from Escherichia coli on mouse haematopoiesis
Autorzy:
Gadomski, T.
Kondracka, E.
Szmitkowski, M.
Powiązania:
https://bibliotekanauki.pl/articles/2187885.pdf
Data publikacji:
1985
Wydawca:
Polskie Towarzystwo Diagnostyki Laboratoryjnej
Źródło:
Diagnostyka Laboratoryjna; 1985, 21, 3; 148-154
0867-4043
Pojawia się w:
Diagnostyka Laboratoryjna
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A comparison between the crystal and solution structures of Escherichia coli asparaginase II.
Autorzy:
Kozak, Maciej
Jurga, Stefan
Powiązania:
https://bibliotekanauki.pl/articles/1043790.pdf
Data publikacji:
2002
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
structure in solution
small angle X-ray scattering
asparaginase
Opis:
The small angle X-ray scattering (SAXS) pattern of the homotetrameric asparaginase II from Escherichia coli was measured in solution in conditions resembling those in which its crystal form was obtained and compared with that calculated from the crystallographic model. The radius of gyration measured by SAXS is about 5% larger and the maximum dimension in the distance distribution function about 12% larger than the corresponding value calculated from the crystal structure. A comparison of the experimental and calculated distance distribution functions suggests that the overall quaternary structure in the crystal and in solution are similar but that the homotetramer is less compact in solution than in the crystal.
Źródło:
Acta Biochimica Polonica; 2002, 49, 2; 509-513
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Wpływ kwaśnego odczynu na szczepy Escherichia coli 0157 izolowane z wody powierzchniowej i materiału klinicznego
The influence of acidity on Escherichia coli 0157 strains isolated from surface water and clinical material
Autorzy:
Michalska-Szymaszek, M.
Powiązania:
https://bibliotekanauki.pl/articles/876083.pdf
Data publikacji:
2009
Wydawca:
Narodowy Instytut Zdrowia Publicznego. Państwowy Zakład Higieny
Opis:
Szczepy E. coli O 157 wyizolowane z wody powierzchniowej i od człowieka chorego testowano na zdolność do przeżywania i namnażania się w podłożu o pH≤7 (w środowisku kwaśnym). Badania przeprowadzono w bulionie TSB zakwaszonym 1M HCl w temperaturach 5ºC, 25ºC, 36ºC w czasie 0, 5 h i 24 h. Badania wykazały, że niektóre z badanych szczepów E. coli O157 mają zdolność przeżywania w niskim pH=2 i 3 przez co najmniej 5 h w temperaturach 5ºC, 25ºC i 36ºC. Szczepy E. coli O157 wyizolowane z wody mają zdolność wzrostu w temp. 25 ºC już w pH=4, natomiast E. coli O157 wyizolowana od człowieka przy pH>4. Można domniemywać, że kwasotolerancja umożliwia badanym szczepom stanie się patogenami dla człowieka.
E. coli O157 strains isolated from surface water and from a sick human were tested for their ability to survive in environment with pH≤7. Examinations were carried on TSB broth with pH range ≤ 7 (modified with 1M HCl) in temperatures 5ºC, 25ºC, 36ºC after 5 hours and 24 hours. It was shown that some of E. coli O157 strains have the survival ability in acid medium pH=2 and 3 within 5h in temperatures 5ºC, 25ºC, 36ºC. E. coli O157 strain, of human origin, grows at pH>4 in temp. 25°C and strain E. coli O157 from water at pH = 4 in this temperature. The acid tolerance of E. coli O157 suggested that the strain be came pathogenic for humans.
Źródło:
Roczniki Państwowego Zakładu Higieny; 2009, 60, 3
0035-7715
Pojawia się w:
Roczniki Państwowego Zakładu Higieny
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Biotechnological conversion of glycerol from biofuels to 1,3-propanediol using Escherichia coli
Autorzy:
Przystałowska, Hanna
Lipiński, Daniel
Słomski, Ryszard
Powiązania:
https://bibliotekanauki.pl/articles/1039124.pdf
Data publikacji:
2015
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
bioconversion
biodiesel
carbon source
Escherichia coli
glycerol
1,3-propanediol
Opis:
In the face of shortage of fossil fuel supplies and climate warming triggered by excessive carbon dioxide emission, alternative resources for chemical industry have gained considerable attention. Renewable resources and their derivatives are of particular interest. Glycerol, which constitutes one of the by-products during biodiesel production, is such a substrate. Thus, generated excess glycerol may become an environmental problem, since it cannot be disposed of in the environment. The most promising products obtained from glycerol are polyols, including 1,3-propanediol, an important substrate in the production of synthetic materials, e.g. polyurethanes, unsaturated polyesters, and epoxy resins. Glycerol can be used as a carbon and energy source for microbial growth in industrial microbiology to produce 1,3-propanediol. This paper is a review of metabolic pathways of native producers and E. coli with the acquired ability to produce the diol via genetic manipulations. Culture conditions during 1,3-PDO production and genetic modifications of E. coli used in order to increase efficiency of glycerol bioconversion are also described in this paper.
Źródło:
Acta Biochimica Polonica; 2015, 62, 1; 23-34
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Escherichia coli O104:H4 outbreak - have we learnt a lesson from it?
Autorzy:
Bloch, Sylwia
Felczykowska, Agnieszka
Nejman-Faleńczyk, Bożena
Powiązania:
https://bibliotekanauki.pl/articles/1039632.pdf
Data publikacji:
2012
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
detection methods
Escherichia coli O104:H4
STEC
mobile genetic elements
outbreak
Opis:
Shiga toxin-producing Escherichia coli (STEC) strains belong to the group of pathogens that cause bloody diarrhea and hemorrhagic colitis with often severe complications. The main problem with human pathogenic E. coli strains, including STEC, is a wide spectrum of phenotypes and clinical manifestations. It is related to a variety of exchangeable genetic elements, like plasmids, bacteriophages, transposons and pathogenicity islands, that take part in horizontal gene transfer which influences creation of new dangerous bacterial strains. A good example of this phenomenon is a novel Shiga toxin-producing E. coli O104:H4 serotype that was associated with a widespread and severe foodborne disease outbreak in Germany in 2011. The O104:H4 strain was created by a number of horizontal gene transfer events between two distinct pathogens, resulting in the emergence of the new, atypical strain. That outbreak proved that also rare and unusual serotypes of STEC may be a significant risk factor and that the procedures recommended for STEC detection were not suitable to deal with this kind of pathogens. With respect to new combinations of chromosomal and extrachromosomal elements in susceptible bacterial hosts, epidemics and frequent human infections caused by STEC strains, we suggest that more attention should be paid to the development and improvement of diagnostic methods. It is difficult to determine STEC bacteria by general microbiological, biochemical and immunological assays, because strains can vary dramatically in their phenotypic and serotypic properties. It is postulated that standardized genetic tests, based on detection of features most frequently presented by STEC, particularly those located on easily exchangeable elements (such as Shiga toxin-encoding phages), can be more adequate for STEC detection.
Źródło:
Acta Biochimica Polonica; 2012, 59, 4; 483-488
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Ocena toksyczności nanocząstek srebra w stosunku do lekoopornych szczepów Escherichia coli izolowanych z odpadów komunalnych
Evaluation of silver nanoparticles toxicity to drug-resistant Escherichia coli strains isolated from municipal waste
Autorzy:
Wolny-Koładka, K.
Sikora, A.
Malina, D.
Powiązania:
https://bibliotekanauki.pl/articles/101027.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Stowarzyszenie Infrastruktura i Ekologia Terenów Wiejskich PAN
Tematy:
Escherichia coli
lekooporność
nanocząstki srebra
toksyczność
drug resistance
silver nanoparticles
toxicity
Opis:
Celem pracy była ocena bakteriobójczych właściwości nanocząstek srebra w stosunku do bakterii Escherichia coli. Ponadto, wykonano analizę wrażliwości bakterii E. coli na powszechnie stosowane antybiotyki. W przeprowadzonych badaniach wykorzystano 51 szczepów izolowanych z odpadów komunalnych. Zastosowano wzrastające stężenia nanosrebra: 5, 10, 15, 30, 60 oraz 125 ppm. Kontrolą pozytywną był antybiotyk - ampicylina, negatywną - woda destylowana. Analizę lekooporności wykonano przy pomocy metody dyfuzyjno-krążkowej. Wraz ze wzrostem stężenia nanocząstek srebra, wzrastały ich właściwości antybakteryjne. Najmniejszym stężeniem hamującym wzrost niektórych izolatów było 5 ppm, natomiast najskuteczniejsze było stężenie 125 ppm. Analiza lekooporności wykazała, że antybiotykiem hamującym wzrost największej liczby szczepów E. coli była amikacyna. Ponadto, wykryto szczepy wielolekooporne stanowiące 22%. Nanosrebro posiada duży potencjał bakteriobójczy i może okazać się pomocne w rozwiązaniu problemu lekooporności. Jednak, zasadne jest prowadzenie dalszych badań oceniających wpływ toksyczności nanocząstek na środowisko i organizmy wyższe.
The aim of the study was to evaluate the bactericidal properties of silver nanoparticles against bacteria Escherichia coli. In addition, a sensitivity analysis was made of E. coli to commonly used antibiotics. In the study were used 51 strains isolated from municipal waste. Applied growing concentrations of nanosilver were used: 5, 10, 15, 30, 60 and 125 ppm. The positive control was an antibiotic - ampicillin, negative control - a distilled water. Drug-resistance analysis was performed by disc-diffusion method. Along with the increase in the concentration of silver nanoparticles their antibacterial properties is also growing. The smallest concentration that inhibited growth of some isolates was 5 ppm, while the most effective concentration was 125 ppm. Analysis of drug resistance showed that the antibiotic inhibits growth of a large number of E. coli strains was amikacin. In addition, 22% of all isolates analyzed were drug-resistant. Nanosilver has a high bactericidal potential and may be helpful in solving the problem of drug resistance. However, it is reasonable to conduct further studies on the effects of toxicity of nanoparticles on the environment and higher organisms.
Źródło:
Infrastruktura i Ekologia Terenów Wiejskich; 2018, I/1; 7-23
1732-5587
Pojawia się w:
Infrastruktura i Ekologia Terenów Wiejskich
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Występowanie werotoksycznych Escherichia coli w żywności, ze szczególnym uwzględnienim serotypu O104:H4
Occurrence of verotoxic Escherichia coli in food with particular focus on serotype O104:H4
Autorzy:
Pappelbaum, K.
Kasprzak, J.
Czaczyk, K.
Powiązania:
https://bibliotekanauki.pl/articles/826504.pdf
Data publikacji:
2015
Wydawca:
Polskie Towarzystwo Technologów Żywności
Tematy:
zywnosc
zanieczyszczenia mikrobiologiczne
bakterie
Escherichia coli
wystepowanie
szczepy werotoksyczne
zagrozenia zdrowia
zatrucia pokarmowe
ogniska chorobowe
Opis:
Skażenia mikrobiologiczne związane z żywnością stanowią bardzo istotny problem we współczesnym świecie. Pomimo zaawansowanych technik detekcji mikroorganizmów chorobotwórczych w żywności oraz postępów w leczeniu chorób spowodowanych przez te drobnoustroje, problem nadal pozostaje aktualny. W pracy opisano potencjalne zagrożenia dla ludzi związane z występowaniem werotoksycznych Escherichia coli w żywności. Przedstawiono także charakterystykę serotypu E. coli O104:H4, który był przyczyną dużego ogniska zatrucia, które stwierdzono w Niemczech w 2011 roku. Omówiono występowanie E. coli O104:H4 u ludzi, zwierząt i w żywności oraz występowanie ognisk zatruć spowodowanych przez tę grupę mikroorganizmów.
Microbiological contaminations of food constitute a very significant problem in the modern world. Despite the advanced techniques for detection of pathogenic microorganisms in food and the progress in treating diseases caused by them, the problem is still relevant. In the paper, there are described potential risks to people that are associated with the occurrence of verotoxic E.coli in food. Also, the paper presents a detailed profile of the serotype of E. coli O104:H4, which was a causative agent of the large outbreak of food poisoning in Germany in 2011. The occurrence of E.coli O104:H4 in humans, animals, and foods are discussed as is the occurrence of food-borne outbreaks caused by this group of microorganisms.
Źródło:
Żywność Nauka Technologia Jakość; 2015, 22, 5
1425-6959
Pojawia się w:
Żywność Nauka Technologia Jakość
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of Ionic Liquids on growth of Escherichia coli strain possessing β-galactosidase activity
Autorzy:
Stobińska, M.
Urbański, D.
Bartkowiak, A.
Powiązania:
https://bibliotekanauki.pl/articles/115739.pdf
Data publikacji:
2013
Wydawca:
Fundacja na Rzecz Młodych Naukowców
Tematy:
ionic liquids
β-galactosidase
toxicity
Opis:
Ionic liquids (ILs) have gained a significant attention as alternative solvents in many chemical and biological reactions. ILs have evolved as a new type of non-aqueous solvents for biocatalysis, because they can stabilize and activate enzymes. Ionic liquids to be considered as so called “green solvents” should possess only very low or no toxicity to living organism and the environment. Currently, very little is known about the biotoxicity of ionic liquids. Within this paper a relative toxicity of two ionic liquids 1,3 dimethylimidazolium methyl sulfate [MMIM][MeSO4] and 1-hexyl-3-methylimidazolium chloride [HMIM][Cl]) on the growth of Escherichia coli (E.coli) was evaluated. In this study we focused on ionic liquids, which potentially could increase activity of β-galactosidase produced by selected strain of E. coli. The inhibition of cell growth in the presence of various ionic liquids was determined using both, solid and liquid cultures. Liquid culture was incubated in culture medium with different concentrations of ionic liquids (0.1, 1, 5, 10% (v/v)). Determination of the minimal inhibitory concentration (MIC50) of ionic liquids was based on monitoring of E. coli growth by optical density measured at 600 nm using densitometer. In the second method the solid culture plate with addition of various amount of ILs has been used. The number of colonies formed on the solid culture plate was converted to colony forming units (CFUs). The obtained results have confirmed, that prescreening based on cytotoxicity tests is a key element in selection procedure of ILs for any biotechnological processes based on application of microorganisms.
Źródło:
Challenges of Modern Technology; 2013, 4, 1; 38-40
2082-2863
2353-4419
Pojawia się w:
Challenges of Modern Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Preliminary crystallographic studies of Y25F mutant of periplasmic Escherichia coli L-asparaginase.
Autorzy:
Kozak, Maciej
Jaskólski, Mariusz
Röhm, Klaus
Powiązania:
https://bibliotekanauki.pl/articles/1044330.pdf
Data publikacji:
2000
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
protein crystallography
mutagenesis
leukemia
amidohydrolase
Opis:
Periplasmic Escherichia coli L-asparaginase II with Y25F mutation in the active-site cavity has been obtained by recombinant techniques. The protein was crystallized in a new hexagonal form (P6522). Single crystals of this polymorph, suitable for X-ray diffraction, were obtained by vapor diffusion using 2-methyl-2,4-pentanediol as precipitant (pH 4.8). The crystals are characterized by a = 81.0, c = 341.1 Å and diffract to 2.45 Å resolution. The asymmetric unit contains two protein molecules arranged into an AB dimer. The physiologically relevant ABA'B' homotetramer is generated by the action of the crystallographic 2-fold axis along [1, -1, 0]. Kinetic studies show that the loss of the phenolic hydroxyl group at position 25 brought about by the replacement of Y with F strongly impairs kcat without significantly affecting Km.
Źródło:
Acta Biochimica Polonica; 2000, 47, 3; 807-814
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The relationship between biofilm formation, genes of virulence and iron metabolism in Escherichia coli
Autorzy:
Handrová, Lívia
Čuvalová, Anna
Kmeť, Vladimír
Powiązania:
https://bibliotekanauki.pl/articles/2183556.pdf
Data publikacji:
2018-12-31
Wydawca:
Uniwersytet Pedagogiczny im. Komisji Edukacji Narodowej w Krakowie
Tematy:
biofilm
virulence genes
iron metabolisms genes
Opis:
Escherichia coli is known as one of the bacterial species with the widest adaptability to variety of niches either within organisms or outside in environment. Most strains of E. coli are of low virulence and associated with opportunistic infections, whereas others are highly virulent. The success of E. coli in colonising such a wide range of hosts and environments is basically due to a noticeable ductility in exploiting the available resources. It is becoming increasingly clear that biofilms have an enormous impact on medicine because since 65% of animal and human bacterial infections involve biofilms. In present study, we isolated strains of E. coli from animals. 19 interesting isolates were selected and tested by PCR amplification to virulence - iutA, cvaC, iss, tsh, papC, kps, iha and iron metabolism genes - sitA, feoB, irp2, fyuA, iroN, ireA. The ability of biofilm formation was assessed in a quantitative assay using a microtiter-plate test. Bacterial strains were grown on BHI. We divided isolates of E. coli into four classes: very weak (63.0%), weak (10.5%), moderate (10.5%) and strong (16.0%) biofilm producers. Representation genes of virulence were highly in isolates from very weak biofilm producers - from 7 genes were 6 highly; only papC (P fimbrial adhesin) was low. Genes of iron metabolism were different. Genes - sitA, fyuA, ireA in strong isolates producing biofilm and feoB, irp2, iroN in weak producers were most represented. The results show possible relation between presence virulence factor and low biofilm formation.
Źródło:
Annales Universitatis Paedagogicae Cracoviensis Studia Naturae; 2018, 3 (suppl.); 24-32
2543-8832
2545-0999
Pojawia się w:
Annales Universitatis Paedagogicae Cracoviensis Studia Naturae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Horizontal transfer and functional evaluation of high pathogenicity islands in Avian Escherichia coli
Autorzy:
Tu, J.
Qi, K.
Song, X.
Xue, T.
Ji, H.
Shao, Y.
Liu, H.
Zhou, X.
Zhu, L.
Powiązania:
https://bibliotekanauki.pl/articles/30119.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Opis:
High pathogenicity islands (HPIs) in Escherichia coli encode genes that are primarily involved in iron uptake and regulation, and confer virulence and pathogenicity. The aim of this study was to investigate the transfer of HPIs in avian E. coli and identify the function of HPI in the acceptor strain. The HPI transfer strain was obtained under conditions of low temperature and low iron abundance, and the donor and acceptor strains were confirmed. E. coli HPIs are transferred by horizontal gene transfer events, which are likely mediated primarily by homologous recombination in HPI-adjacent sequences. Assays for biological activity and pathogenicity changes in the acceptor strain indicated that HPIs might not be involved in pathogenesis in avian E. coli, and thus the main function of HPIs in this strain of bacteria may be to regulate iron nutrition.
Źródło:
Polish Journal of Veterinary Sciences; 2017, 20, 2
1505-1773
Pojawia się w:
Polish Journal of Veterinary Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Purification and characterization of GlcNAc-6-P 2-epimerase from Escherichia coli K92
Autorzy:
Ferrero, Miguel
Martínez-Blanco, Honorina
Lopez-Velasco, Federico
Ezquerro-Sáenz, Carlos
Navasa, Nicolas
Lozano, Sofia
Rodríguez-Aparicio, Leandro
Powiązania:
https://bibliotekanauki.pl/articles/1041092.pdf
Data publikacji:
2007
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
sialic acid
capsular polysialic acid
N-acetylglucosamine
2-epimerase
Opis:
N-Acetylmannosamine (ManNAc) is the first committed intermediate in sialic acid metabolism. Thus, the mechanisms that control intracellular ManNAc levels are important regulators of sialic acid production. In prokaryotic organisms, UDP-N-acetylglucosamine (GlcNAc) 2-epimerase and GlcNAc-6-P 2-epimerase are two enzymes capable of generating ManNAc from UDP-GlcNAc and GlcNAc-6-P, respectively. We have purified for the first time native GlcNAc-6-P 2-epimerase from bacterial source to apparent homogeneity (1 200 fold) using Butyl-agarose, DEAE-FPLC and Mannose-6-P-agarose chromatography. By SDS/PAGE the pure enzyme showed a molecular mass of 38.4 ± 0.2 kDa. The maximum activity was achieved at pH 7.8 and 37°C. Under these conditions, the Km calculated for GlcNAc-6-P was 1.5 mM. The 2-epimerase activity was activated by Na+ and inhibited by mannose-6-P but not mannose-1-P. Genetic analysis revealed high homology with bacterial isomerases. GlcNAc-6-P 2-epimerase from E. coli K92 is a ManNAc-inducible protein and is detected from the early logarithmic phase of growth. Our results indicate that, unlike UDP-GlcNAc 2-epimerase, which promotes the biosynthesis of sialic acid, GlcNAc-6-P 2-epimerase plays a catabolic role. When E. coli grows using ManNAc as a carbon source, this enzyme converts the intracellular ManNAc-6-P generated into GlcNAc-6-P, diverting the metabolic flux of ManNAc to GlcNAc.
Źródło:
Acta Biochimica Polonica; 2007, 54, 2; 387-399
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Effect of Heavy Metals on the Growth of Waterborne Escherichia coli of Municipal Landfill Origin
Wpływ metali ciężkich na wzrost Escherichia coli izolowanych z wód pochodzących ze składowiska odpadów komunalnych
Autorzy:
Frączek, K.
Ropek, D.
Lenart-Boroń, A.
Powiązania:
https://bibliotekanauki.pl/articles/388581.pdf
Data publikacji:
2016
Wydawca:
Towarzystwo Chemii i Inżynierii Ekologicznej
Tematy:
municipal waste landfill
Escherichia coli
heavy metals
municipal waste
składowisko odpadów komunalnych
metale ciężkie
odpady komunalne
Opis:
The aim of this study was to assess the sensitivity of Escherichia coli isolates originating from a municipal waste landfill to the selected heavy metals. The analyses were conducted using environmental strains, isolated from surface water – a stream flowing along the landfill and from leachate and the observations were compared to the reaction of a reference strain EC ATCC 25922. The growth rate of bacterial cultures was evaluated in the liquid medium supplemented with 0.02; 0.1 and 0.5 mg dm–3 of heavy metal salts: chromium, zinc, cadmium, copper, lead and mercury. The bacterial growth was examined turbidimetrically every 24 hours for 5 days. The performed study showed differences between the examined isolates in their response to the addition of the heavy metals in the liquid medium. Additionally, varied intensity of the heavy metals’ effect on bacterial growth was observed, with the weakest growth inhibition being recorded in the case of lead, while chromium and mercury causing the greatest growth inhibition of bacterial strains.
Celem pracy była ocena wrażliwości izolatów Escherichia coli, pochodzących ze składowiska odpadów komunalnych na działanie wybranych metali ciężkich. Badaniu poddano izolaty środowiskowe, pochodzące z wody powierzchniowej – strumienia płynącego wzdłuż składowiska oraz z odcieków, a także szczep wzorcowy EC ATCC 25922. Ocenie poddano tempo wzrostu kultur bakteryjnych w podłożu płynnym z dodatkiem 0,02; 0,1 oraz 0,5 mg dm–3 soli metali ciężkich: chromu, cynku, kadmu, miedzi, ołowiu i rtęci. The Effect of Heavy Metals on the Growth of Waterborne Escherichia coli... 183 Wzrost bakterii badano turbidymetrycznie w odstępach 24-godzinnych przez okres 5 dni. Na podstawie przeprowadzonych badań stwierdzono różnice pomiędzy badanymi izolatami w ich reakcji na obecność badanych metali ciężkich w podłożu. Zaobserwowano także różną intensywność działania metali, przy czym najsłabsze zahamowanie wzrostu bakterii stwierdzono w przypadku ołowiu, natomiast najsilniejszy efekt hamujący miały chrom i rtęć.
Źródło:
Ecological Chemistry and Engineering. A; 2016, 23, 2; 173-184
1898-6188
2084-4530
Pojawia się w:
Ecological Chemistry and Engineering. A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Wound healing potential of Capparis spinosa against cutaneous wounds infected by Escherichia coli in a rat model
Możliwość leczenia ran ciętych zainfekowanych Escherichia coli za pomocą Capparis spinosa na modelu szczurzym
Autorzy:
Asheghian Amiri, I.
Moslemi, H.R.
Tehrani-Sharif, M.
Kafshdouzan, K.
Powiązania:
https://bibliotekanauki.pl/articles/72825.pdf
Data publikacji:
2015
Wydawca:
Instytut Włókien Naturalnych i Roślin Zielarskich
Tematy:
wound
cutaneous wound
Escherichia coli
wound infection
treatment
Capparis spinosa
plant extract
ethanol extract
rat
animal model
Opis:
Wound infection has become a major medical problem in recent years. This study was conducted to evaluate the healing activity of Capparis spinosa against surgical wounds infected by Escherichia coli. Twenty male rats were divided into two groups. Excisions were created surgically on the animals’ skin and then infected with E coli. Group 1 was treated with C spinosa while Group 2 was untreated. Wound biopsy specimens were collected on days 5, 10 and 16 and analyzed. Results showed that the hydroxyproline content in treatment group was significantly higher in various post wounding days. Protein content increased gradually in ten days. Results of histopathological studies showed moderate to intense granulation tissue formation in treated group on day 10. The histopathological studies showed, that the new epidermis in treated group was thicker than in control group on day 16 post wounding. The present study has demonstrated that ethanol extract of C spinosa includes properties that accelerate wound healing activities.
Infekcje ran stały się ostatnio dużym problemem medycznym. W prezentowanym artykule przedstawiono badania przeprowadzone w celu określenia działania Capparis spinosa przeciwko infekcjom ran pooperacyjnych przez Escherichia coli. Dwadzieścia szczurów płci męskiej podzielono na dwie grupy. Skórę zwierząt nacięto operacyjnie, a następnie ranę zainfekowano E coli. Grupę 1 leczono C spinosa, grupa 2 nie była leczona. Biopsję ran przeprowadzono 5., 10. i 16. dnia, a następnie poddano analizie. Wyniki wykazały, że zawartość hydroksyproliny w grupie leczonej była wyraźnie wyższa w poszczególnych dniach następujących po powstaniu rany. Zawartość białka rosła stopniowo przez 10 dni. Obserwacje histopatologiczne wskazywały na umiarkowaną do intensywnej granulację tkanki w grupie leczonej 10. dnia. Na ich podstawie stwierdzono również, że nowa epiderma w grupie leczonej była grubsza niż w grupie kontrolnej po 16 dniach od zranienia. Prezentowane badania wskazują, że wyciąg etanolowy z C spinosa ma właściwości przyspieszające gojenie się ran.
Źródło:
Herba Polonica; 2015, 61, 2
0018-0599
Pojawia się w:
Herba Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Antibiotic resistance among Escherichia coli urinary isolates and their susceptibility to clove essential oil
Autorzy:
Dąbrowski, Michał
Sienkiewicz, Monika
Zielińska-Bliźniewska, Hanna
Dąbrowska, Marta
Seredyńska, Małgorzata
Kochan, Ewa
Powiązania:
https://bibliotekanauki.pl/articles/763827.pdf
Data publikacji:
2016
Wydawca:
Uniwersytet Marii Curie-Skłodowskiej. Wydawnictwo Uniwersytetu Marii Curie-Skłodowskiej
Tematy:
Escherichia coli, clove oil, urinary tract infections
Opis:
Escherichia coli is a Gram-negative, facultatively anaerobic, rod-shaped, coliform bacterium, which is a primary cause of urinary tract infections. Resistance to antibiotics has become a particular problem in recent decades. Consequently, there is an unmet need for new therapeutic options. It has been observed that essential oils have bactericidal effects. The antimicrobial susceptibility testing for Escherichia coli isolates obtained from urine of patients with urinary tract infections was determined via disk diffusion method according to the European Committee on Antimicrobial Susceptibility Testing (EUCAST, 2015). Essential oil from clove – Syzygium aromaticum (L.) Merill et L.M. (Myrtaceae) was analyzed by GC-FID-MS. Minimal Inhibitory Concentration (MIC) and Minimal Bactericidal Concentration (MBC) were detected by using the micro-dilution broth method. Escherichia coli clinical isolates are characterized by high resistance to ampicillin, amoxicillin with clavulanic acid, norfloxacin, trimethoprim/sulfamethoxazole, tetracycline, tobramycin and ticarcillin. Clove oil possesses strong inhibiting and killing properties against E. coli isolates, among them the ones resistant to recommended antibiotics. The results of this study highlight the need for testing the efficacy of new agents to inactivate bacteria in clinical settings.
Źródło:
Annales Universitatis Mariae Curie-Sklodowska, sectio C – Biologia; 2016, 71, 2
2083-3563
0066-2232
Pojawia się w:
Annales Universitatis Mariae Curie-Sklodowska, sectio C – Biologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
1,3-Propanediol production by Escherichia coli using genes from Citrobacter freundii atcc 8090
Autorzy:
Przystałowska, Hanna
Zeyland, Joanna
Kośmider, Alicja
Szalata, Marlena
Słomski, Ryszard
Lipiński, Daniel
Powiązania:
https://bibliotekanauki.pl/articles/1039012.pdf
Data publikacji:
2015
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
bio-based 1,3-propanediol
genetically modified bacteria
glycerol utilization
renewable resources
Citrobacter freundii
Escherichia coli
Opis:
Compared with chemical synthesis, fermentation has the advantage of mass production at low cost, and has been used in the production of various industrial chemicals. As a valuable organic compound, 1,3-propanediol (1,3-PDO) has numerous applications in the production of polymers, lubricants, cosmetics and medicines. Here, conversion of glycerol (a renewable substrate and waste from biodiesel production) to 1,3-PDO by E. coli bacterial strain carrying altered glycerol metabolic pathway was investigated. Two gene constructs containing the 1,3-PDO operon from Citrobacter freundii (pCF1 and pCF2) were used to transform the bacteria. The pCF1 gene expression construct contained dhaBCE genes encoding the three subunits of glycerol dehydratase, dhaF encoding the large subunit of the glycerol dehydratase reactivation factor and dhaG encoding the small subunit of the glycerol dehydratase reactivating factor. The pCF2 gene expression construct contained the dhaT gene encoding the 1,3-propanediol dehydrogenase. Expression of the genes cloned in the above constructs was under regulation of the T7lac promoter. RT-PCR, SDS-PAGE analyses and functional tests confirmed that 1,3-PDO synthesis pathway genes were expressed at the RNA and protein levels, and worked flawlessly in the heterologous host. In a batch flask culture, in a short time applied just to identify the 1,3-PDO in a preliminary study, the recombinant E. coli bacteria produced 1.53 g/L of 1,3-PDO, using 21.2 g/L of glycerol in 72 h. In the Sartorius Biostat B Plus reactor, they produced 11.7 g/L of 1,3-PDO using 24.2 g/L of glycerol, attaining an efficiency of 0.58 [mol1,3-PDO/molglycerol].
Źródło:
Acta Biochimica Polonica; 2015, 62, 3; 589-597
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Cloning and purification of functionally active Fas ligand interfering protein (FIP) expressed in Escherichia coli
Autorzy:
Wisniewski, Pawel
Master, Adam
Kaminska, Bozena
Powiązania:
https://bibliotekanauki.pl/articles/1040813.pdf
Data publikacji:
2008
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
Fas ligand
interfering molecules
recombinant protein purification
Fas
apoptosis
Opis:
This report presents purification and characterization of the extracellular domain of rat Fas protein, called FIP (FasL interfering protein), expressed as inclusion bodies in Escherichia coli. FIP was extracted from the inclusion bodies, solubilized with 8 M urea, purified by a single-step immobilized metal ion (Ni2+) affinity chromatography and refolded. SDS/PAGE and mass spectrometry analysis of the purified protein verified its purity. Fluorescence spectrum analysis showed that the refolding procedure caused structural changes which presumably might have led to oligomerization. The purified FIP has biological activities: it binds specifically soluble Fas ligand and protects human Jurkat lymphocytes against FasL-dependent apoptosis. This efficient procedure of FIP expression in E. coli and renaturation may be useful for production of therapeutically important proteins.
Źródło:
Acta Biochimica Polonica; 2008, 55, 1; 51-56
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Thermodynamic aspects of the self-assembly of DsrA, a small noncoding RNA from Escherichia coli
Autorzy:
Geinguenaud, Frédéric
Gesson, Maeva
Arluison, Véronique
Powiązania:
https://bibliotekanauki.pl/articles/1039361.pdf
Data publikacji:
2014
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
DsrA
small noncoding RNA
nucleic acid self-assembly
RNA nanotechnology
Opis:
DsrA is an Escherichia coli small noncoding RNA that acts by base pairing to some mRNAs in order to control their translation and turnover. It was recently shown that DsrA is able to self-associate in a way similar to DNA and to build nanostructures. Although functional consequence of this RNA self-assembly in vivo is not yet understood, the formation of such an assemblage more than likely influences the noncoding RNA function. We report here for the first time the thermodynamic basis of this natural RNA self-assembly. In particular we show that assembling of the ribonucleic acid is enthalpy driven and that the versatility of the RNA molecule is important for the polymerisation; indeed, an equivalent DNA sequence is unable to make a nanoassembly. The origin of the difference is discussed herein.
Źródło:
Acta Biochimica Polonica; 2014, 61, 1; 179-184
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A search for the in trans role of GraL, an Escherichia coli small RNA
Autorzy:
Dylewski, Maciej
Ćwiklińska, Monika
Potrykus, Katarzyna
Powiązania:
https://bibliotekanauki.pl/articles/1038537.pdf
Data publikacji:
2018
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
GraL
GreA
sRNA
sRNA targets
synthetic lethal genes
Opis:
Small RNA are very important post-transcriptional regulators in both, bacteria and eukaryotes. One of such sRNA is GraL, encoded in the greA leader region and conserved among enteric bacteria. Here, we conducted a bioinformatics search for GraL's targets in trans and validated our findings in vivo by constructing fusions of probable targets with lacZ and measuring their activity when GraL was overexpressed. Only one target's activity (nudE) decreased under those conditions and was thus selected for further analysis. In the absence of GraL and greA, the nudE::lacZ fusion's β-galactosidase activity was increased. However, a similar effect was also visible in the strain deleted only for greA. Furthermore, overproduction of GreA alone increased the nudE::lacZ fusion's activity as well. This suggests existence of complex regulatory loop-like interactions between GreA, GraL and nudE mRNA. To further dissect this relationship, we performed in vitro EMSA experiments employing GraL and nudE mRNA. However, stable GraL-nudE complexes were not detected, even though the detectable amount of unbound GraL decreased as increasing amounts of nudE mRNA were added. Interestingly, GraL is being bound by Hfq, but nudE easily displaces it. We also conducted a search for genes that are synthetic lethal when deleted along with GraL. This revealed 40 genes that are rendered essential by GraL deletion, however, they are involved in many different cellular processes and no clear correlation was found. The obtained data suggest that GraL's mechanism of action is non-canonical, unique and requires further research.
Źródło:
Acta Biochimica Polonica; 2018, 65, 1; 141-149
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Wybrane podłoże kompleksowe do szybkiej diagnostyki Enterobacteriaceae w zastosowaniu do badań pałeczki okrężnicy (Escherichia coli)
The application of the selected complex culture media used for rapid diagnosis of Enterobacteriaceae to Escherichia coli detection
Autorzy:
Hendrich, Z.
Powiązania:
https://bibliotekanauki.pl/articles/2189764.pdf
Data publikacji:
1970
Wydawca:
Polskie Towarzystwo Diagnostyki Laboratoryjnej
Źródło:
Diagnostyka Laboratoryjna; 1970, 06, 2; 169-178
0867-4043
Pojawia się w:
Diagnostyka Laboratoryjna
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Design of small molecule inhibitors of type III secretion system ATPase EscN from enteropathogenic Escherichia coli
Autorzy:
Bzdzion, Lukasz
Krezel, Hanna
Wrzeszcz, Karol
Grzegorek, Irmina
Nowinska, Katarzyna
Chodaczek, Grzegorz
Swietnicki, Wieslaw
Powiązania:
https://bibliotekanauki.pl/articles/1038684.pdf
Data publikacji:
2017
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
Escherichia coli (E. coli)
type III secretion system (T3SS)
enzyme inhibitor
small molecule
Opis:
Enteropathogenic E. coli (EPEC) is a human pathogen using type III secretion system for delivery of proteins directly into the human host. The system contains a single ATPase, EscN, which is essential for uncoupling of proteins from their complexes with chaperones before the delivery. The structure of EscN ATPase (PDB code: 2obm) was used to screen computationally for small molecule inhibitors blocking its active site. Two lead candidates were examined but only one, Compound 54, was selected for further optimization. After extended QSAR optimization, two derivatives were found to be competitive inhibitors of EscN capable of blocking ATPase activity with a Ki below 50 µM. One candidate, WEN05-03, with a Ki=16±2 µM, was also minimally toxic to mammalian cells as determined by other assays. In the cell infection model of HeLa cells with EPEC, Compound WEN05-03 completely blocked actin cluster formation at 100 µM concentration, when analyzed by confocal microscopy. The second best inhibitor of EscN ATPase activity was WEN04-34 with a Ki=46±2 µM. However, the compound was highly toxic to the BALB/3T3 cell line. In summary, the work identifies a compound blocking bacterial ATPase in its active site without causing cellular toxicity to the host cells. It is the first report showing feasibility of using bacterial virulence system ATPase as a target for safe, non-toxic compounds and offering a proof-of-concept for non-antibiotic alternatives.
Źródło:
Acta Biochimica Polonica; 2017, 64, 1; 49-63
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Application of an aptamer and a reagent based on gold nanoparticles for detection of Escherichia coli
Autorzy:
Pięta, P. P.
Szczerba, A.
Dobroczyńska, J. I.
Grabas, K.
Powiązania:
https://bibliotekanauki.pl/articles/207434.pdf
Data publikacji:
2013
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
Escherichia coli
złoto
aptamery
komórki bakteryjne
nanocząstki złota
zawiesiny wodne
gold
aptamers
bacterial cells
gold nanoparticles
water suspensions
Opis:
Plates functionalized with an Escherichia coll binding aptamer and a reagent based on gold nanoparticles were used for the detection of bacterial cells. Bacteria suspended in samples were caught by specific aptamers immobilized on a plastic plate whereas the gold nanoparticle reagent is an indicator reagent for visualization of the test result. Changes in colour of the gold nanoparticle reagent caused by gold nanoparticle agglomeration were observed with the naked eye. The test was designed for the detection of Escherichia coli in water suspensions.
Źródło:
Environment Protection Engineering; 2013, 39, 4; 125-133
0324-8828
Pojawia się w:
Environment Protection Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
7-Deazapurine 2-deoxyribofuranosides are noncleavable competitive inhibitors of Escherichia coli purine nucleoside phosphorylase (PNP)
Autorzy:
Bzowska, Agnieszka
Kazimierczuk, Zygmunt
Seela, Frank
Powiązania:
https://bibliotekanauki.pl/articles/1044781.pdf
Data publikacji:
1998
Wydawca:
Polskie Towarzystwo Biochemiczne
Źródło:
Acta Biochimica Polonica; 1998, 45, 3; 755-768
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Expression of goose parvovirus whole VP3 protein and its epitopes in Escherichia coli cells
Autorzy:
Tarasiuk, K.
Wozniakowski, G.
Holec-Gasior, L.
Powiązania:
https://bibliotekanauki.pl/articles/32169.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Opis:
The aim of this study was the expression of goose parvovirus capsid protein (VP3) and its epitopes in Escherichia coli cells. Expression of the whole VP3 protein provided an insufficient amount of protein. In contrast, the expression of two VP3 epitopes (VP3ep4, VP3ep6) in E. coli, resulted in very high expression levels. This may suggest that smaller parts of the GPV antigenic determinants are more efficiently expressed than the complete VP3 gene.
Źródło:
Polish Journal of Veterinary Sciences; 2015, 18, 4
1505-1773
Pojawia się w:
Polish Journal of Veterinary Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Rapid detection and enumeration of coliforms and Escherichia coli in River Nile using membrane filtration technique
Autorzy:
Shash, S. M.
Kamel, M. M.
Al-Wasify, R. S.
Samhan, F. A.
Powiązania:
https://bibliotekanauki.pl/articles/363162.pdf
Data publikacji:
2010
Wydawca:
Uniwersytet Warmińsko-Mazurski w Olsztynie
Tematy:
filtracja membranowa
Nil rzeka
bakterie grupy coli
membrane filtration
Nile river
total coliforms
Opis:
The purpose of this investigation was to compare Rapid Hicoliform Agar® (RHA, Himedia, India) with the conventional m-Endo Agar (DIFCO, Michigan, USA) for detection and enumeration of Total Coliforms (TC) and with the conventional Seven Hour Fecal Coliforms Agar (7hFC) for detection and enumeration of Escherichia coli using Membrane Filtration (MF) in River Nile water, Egypt. Sixty samples were collected (five samples per month) from five regions (Kafr El-Elw, El-Maasara, El-Giza, Embaba and El-Galatma) during one year (December 2005-November 2006). The results showed that total coliforms counts ranged from 103 to 104 CFU*100ml-1 using RHA but using m-Endo Agar the counts were around 104 CFU*100ml-1. Escherichia coli counts ranged from 103 to 104 CFU*100ml-1 using 7hFC Agar, while using RHA the counts ranged from 103 to 104 CFU*100ml-1. Statistical analysis showed that there was no significant difference (p=0.423) between total coliforms counts using m-Endo Agar and RHA media, also, there was no significant difference (p=0.546) between fecal coliforms (E. coli) counts using 7hFC Agar and RHA media. We conclude that RHA is a potential alternative medium for detection and enumeration of total coliforms and E. coli at the same time and the same Petri dish within 24h. Also, RHA medium was a very sensitive medium, which did not require any confirmatory tests and secured rapid recovery of total coliforms or E. coli.
Źródło:
Environmental Biotechnology; 2010, 6, 1; 6-10
1734-4964
Pojawia się w:
Environmental Biotechnology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Escherichia Coli-Lux Biosensor Used to Monitor the Cytotoxicity and Genotoxicity of Pharmacological Residues in Environment
Autorzy:
Hawrylik, E.
Matejczyk, M.
Powiązania:
https://bibliotekanauki.pl/articles/124989.pdf
Data publikacji:
2018
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
bacterial biosensors
reporter gene lux
β-blockers
cytotoxicity
genotoxicity
Opis:
The aim of the study was to evaluate the usefulness of Escherichia coli K-12 RFM 443 recA::lux for cytotoxicity and genotoxicity monitoring of metoprolol in the environment. Metoprolol is one of the most popular cardiac drug which belongs to the group of β-blockers. The drug was applied at the concentrations ranging from 0.01 μg/cm3 to 100 μg/cm3. The conducted research constitutes preliminary study aimed at validation of the recA::lux gene construct in order to determine its sensitivity to metoprolol. The drug concentrations were selected experimentally to obtain a positive luminescence response. The obtained data indicated the influence of metoprolol on lux gene expression and recA promoter activity based on the application of laboratory samples using PBS buffer. The results indicate a potential for using a bacterial biosensor Escherichia coli K-12 RFM 443 with recA::lux gene fusion in cytotoxicity and genotoxicity monitoring of the cardiac drugs residue in the environment.
Źródło:
Journal of Ecological Engineering; 2018, 19, 3; 11-17
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Escherichia coli small heat shock proteins IbpA/B enhance activity of enzymes sequestered in inclusion bodies.
Autorzy:
Kuczyńska-Wiśnik, Dorota
Żurawa-Janicka, Dorota
Narkiewicz, Joanna
Kwiatkowska, Joanna
Lipińska, Barbara
Laskowska, Ewa
Powiązania:
https://bibliotekanauki.pl/articles/1041504.pdf
Data publikacji:
2004
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
protein aggregation
inclusion bodies
IbpA/B
Opis:
Escherichia coli small heat shock proteins, IbpA/B, function as molecular chaperones and protect misfolded proteins against irreversible aggregation. IbpA/B are induced during overproduction of recombinant proteins and bind to inclusion bodies in E. coli cells. We investigated the effect of ΔibpA/B mutation on formation of inclusion bodies and biological activity of enzymes sequestered in the aggregates in E. coli cells. Using three different recombinant proteins: Cro-β-galactosidase, β-lactamase and rat rHtrA1 we demonstrated that deletion of the ibpA/B operon did not affect the level of produced inclusion bodies. However, in aggregates containing IbpA/B a higher enzymatic activity was detected than in the IbpA/B-deficient inclusion bodies. These results confirm that IbpA/B protect misfolded proteins from inactivation in vivo.
Źródło:
Acta Biochimica Polonica; 2004, 51, 4; 925-931
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Escherichia coli RNA polymerase α subunit and transcriptional activation by bacteriophage λ CII protein
Autorzy:
Gabig, Magdalena
Obuchowski, Michał
Ciesielska, Agnieszka
Latała, Barbara
Węgrzyn2, Alicja
Thomas, Mark
Węgrzyn, Grzegorz
Powiązania:
https://bibliotekanauki.pl/articles/1044881.pdf
Data publikacji:
1998
Wydawca:
Polskie Towarzystwo Biochemiczne
Źródło:
Acta Biochimica Polonica; 1998, 45, 1; 271-280
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Estimation of significance of AlkB and AlkA proteins in DNA repair in Escherichia coli model
Autorzy:
Sokołowska, B.
Maciejewska, A. M.
Jóźwik, A.
Kuśmierek, J. T.
Powiązania:
https://bibliotekanauki.pl/articles/333316.pdf
Data publikacji:
2011
Wydawca:
Uniwersytet Śląski. Wydział Informatyki i Nauki o Materiałach. Instytut Informatyki. Zakład Systemów Komputerowych
Tematy:
rozpoznawanie obrazów
klasyfikator najbliższych sąsiadów
analiza cech pracy odbiornika
naprawa DNA
adaptacyjna odpowiedź
powstawanie mutacji
bakterie e.coli
pattern recognition
fuzzy k-NN classifier
ROC analysis
DNA repair
adaptive response
mutagenesis
AlkB dioxygenase
AlkA glycosylase
E.coli
Opis:
The paper concerns estimation of significance of differences of mutagenesis level between the wild-type strain (wt) and its derivatives which differ in DNA repair ability, namely alkA and alkB strain, devoided AlkA glycosylase and AlkB dioxygenase activity, respectively. The strains were analyzed for their ability to repair 1,N6-ethenoadenine (εA) - chloroacetaldehyde adduct to DNA. The analysis was done using classical statistical and pattern recognition methods. The obtained results confirmed that AlkB dioxygenase plays the most important role in εA repair in E. coli in the experimental modeling.
Źródło:
Journal of Medical Informatics & Technologies; 2011, 17; 321-326
1642-6037
Pojawia się w:
Journal of Medical Informatics & Technologies
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Escherichia coli - gfp biosensors used to monitor the biological activity of carmustine residues in surface water
Autorzy:
Matejczyk, M.
Jabłońska-Trypuć, A.
Rosochacki, S. J.
Powiązania:
https://bibliotekanauki.pl/articles/402643.pdf
Data publikacji:
2015
Wydawca:
Politechnika Białostocka. Oficyna Wydawnicza Politechniki Białostockiej
Tematy:
environmental monitoring
gfp biosensor
carmustine
cytotoxity
genotoxity
monitoring środowiska
GFP biosensor
karmustyna
cytotoksyczność
genotoksyczność
Opis:
Three genetic constructs with transcriptional fusion of recA, kat G and sodA genotoxin and genotoxin sensitive promoters with green fluorescent protein (gfp) reporter gene in Escherichia coli have been used for assessment of cytotoxic and genotoxic activity of carmustine in surface water. For experiments, the drug was used at concentrations of 0,01; 0,001; 0,0001; 0,00001 and 0,000001 mg/ml. Bacteria strains were incubated with carmustine for 3 and 24 hours. Experimental data showed different sensitivity of applied promoters for the same concentrations of carmustine. Obtained results indicated that, recA::gfpmut2, katG::gfpmut2 and sodA::gfpmut2 genetic systems were sensitive to carmustine, especially at the concentrations of 0,001; 0,0001 and 0,00001 mg/ml. The strongest reactivity was noticed for recA promoter (FI = 14,64). The results indicated that gfp E. coli strains with recA, katG and sodA could be potentially useful for monitoring of cyto- and genotoxic effect of pharmacist residues in surface water.
Źródło:
Budownictwo i Inżynieria Środowiska; 2015, 6, 3; 131-136
2081-3279
Pojawia się w:
Budownictwo i Inżynieria Środowiska
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Sequence-specific p53 gene damage by chloroacetaldehyde and its repair kinetics in Escherichia coli
Autorzy:
Kowalczyk, Paweł
Cieśla, Jarosław
Saparbaev, Murat
Laval, Jacques
Tudek, Barbara
Powiązania:
https://bibliotekanauki.pl/articles/1041247.pdf
Data publikacji:
2006
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
chloroacetaldehyde
p53
replication
exocyclic DNA adducts
vinyl chloride
LM-PCR
DNA repair
sequence-specific DNA damage
Opis:
Oxidative stress and certain environmental carcinogens, e.g. vinyl chloride and its metabolite chloroacetaldehyde (CAA), introduce promutagenic exocyclic adducts into DNA, among them 1,N6-ethenoadenine (εA), 3,N4-ethenocytosine (εC) and N2,3-ethenoguanine (εG). We studied sequence-specific interaction of the vinyl-chloride metabolite CAA with human p53 gene exons 5-8, using DNA Polymerase Fingerprint Analysis (DPFA), and identified sites of the highest sensitivity. CAA-induced DNA damage was more extensive in p53 regions which revealed secondary structure perturbations, and were localized in regions of mutation hot-spots. These perturbations inhibited DNA synthesis on undamaged template. We also studied the repair kinetics of CAA-induced DNA lesions in E. coli at nucleotide resolution level. A plasmid bearing full length cDNA of human p53 gene was modified in vitro with 360 mM CAA and transformed into E. coli DH5α strain, in which the adaptive response system had been induced by MMS treatment before the cells were made competent. Following transformation, plasmids were re-isolated from transformed cultures 35, 40, 50 min and 1-24 h after transformation, and further subjected to LM-PCR, using ANPG, MUG and Fpg glycosylases to identify the sites of DNA damage. In adaptive response-induced E. coli cells the majority of DNA lesions recognized by ANPG glycosylase were removed from plasmid DNA within 35 min, while MUG glycosylase excised base modifications only within 50 min, both in a sequence-dependent manner. In non-adapted cells resolution of plasmid topological forms was perturbed, suggesting inhibition of one or more bacterial topoisomerases by unrepaired ε-adducts. We also observed delayed consequences of DNA modification with CAA, manifesting as secondary DNA breaks, which appeared 3 h after transformation of damaged DNA into E. coli, and were repaired after 24 h.
Źródło:
Acta Biochimica Polonica; 2006, 53, 2; 337-347
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Antimicrobial resistance of Escherichia coli and Klebsiella spp. conventionally sampled from factory-farmed chickens – clinical submissions
Autorzy:
Majewski, M.
Józefiak, A.
Kimsa-Furdzik, M.
Dziubdziela, L.
Hudak-Nowak, M.
Wilczyński, J.
Anusz, K.
Powiązania:
https://bibliotekanauki.pl/articles/28762783.pdf
Data publikacji:
2021
Wydawca:
Instytut Medycyny Wsi
Źródło:
Annals of Agricultural and Environmental Medicine; 2021, 28, 2; 271-276
1232-1966
Pojawia się w:
Annals of Agricultural and Environmental Medicine
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Cloning, purification and enzymatic characterization of recombinant human superoxide dismutase 1 (hSOD1) expressed in Escherichia coli
Autorzy:
Lin, Feng
Yan, Dandan
Chen, Yawen
E, Fletcher
Shi, Haifeng
Han, Bangxing
Zhou, Yang
Powiązania:
https://bibliotekanauki.pl/articles/1038395.pdf
Data publikacji:
2018
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
superoxide dismutase 1
Escherichia coli
soluble expression
metal ions
catalytic activity
Opis:
Superoxide dismutase 1 (SOD1) is a metalloenzyme that catalyzes the disproportionation of superoxide into molecular oxygen and hydrogen peroxide. In this study, the human SOD1 (hSOD1) gene was cloned, expressed and purified. The hSOD1 gene was amplified from a pool of Bxpc3 cell cDNAs by PCR and cloned into expression vector pET-28a (+). The recombinant soluble hSOD1 was expressed in E. coli BL21 (DE3) at 37°C and purified using nickel column affinity chromatography. Soluble hSOD1 was produced with a yield of 5.9 μg/mL medium. As metal ions can have a certain influence on protein structure and activity, we researched the influences of different concentrations of Cu2+ and Zn2+ on hSOD1 activity at induction and the time of activity detection. The results implied that Cu2+ and Zn2+ do not enhance SOD1 expression and solubility; they can, however, improve the catalytic activity at induction. Meanwhile, Cu2+ and Zn2+ also enhanced the enzyme activity at the time of detection. Furthermore, most other bivalent cations had the potential to replace Zn2+ and Cu2+, and also improved enzyme activity at the time of detection.
Źródło:
Acta Biochimica Polonica; 2018, 65, 2; 235-240
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effectiveness bacteriolysis of Shiga toxin-producing Escherichia coli O157: H7 caused by specific bacteriophage isolated from pig slurry
Efektywna bakterioliza Shigatoksycznych szczepów Escherichia coli O157: H7 spowodowana przez specyficznego bakteriofaga wyizolowanego ze świńskiej gnojowicy
Autorzy:
Grygorcewicz, B.
Struk, M.
Wasak, A.
Nawrotek, P.
Powiązania:
https://bibliotekanauki.pl/articles/44668.pdf
Data publikacji:
2015
Wydawca:
Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
Źródło:
Acta Scientiarum Polonorum. Zootechnica; 2015, 14, 1
1644-0714
Pojawia się w:
Acta Scientiarum Polonorum. Zootechnica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Spontaneous mutagenesis in exponentially growing and stationary-phase, umuDC-proficient and -deficient, Escherichia coli dnaQ49.
Autorzy:
Nowosielska, Anetta
Nieminuszczy, Jadwiga
Grzesiuk, Elżbieta
Powiązania:
https://bibliotekanauki.pl/articles/1041546.pdf
Data publikacji:
2004
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
dnaQ49
argE3→Arg+ revertants
E. coli
Pol V
spontaneous mutagenesis
stationary-phase mutations
Opis:
Spontaneous mutations arise not only in exponentially growing bacteria but also in non-dividing or slowly dividing stationary-phase cells. In the latter case mutations are called adaptive or stationary-phase mutations. High spontaneous mutability has been observed in temperature sensitive Escherichia coli dnaQ49 strain deficient in 3'→5' proofreading activity assured by the ε subunit of the main replicative polymerase, Pol III. The aim of this study was to evaluate the effects of the dnaQ49 mutation and deletion of the umuDC operon encoding polymerase V (Pol V) on spontaneous mutagenesis in growing and stationary-phase E. coli cells. Using the argE3OC →Arg+ reversion system in the AB1157 strain, we found that the level of growth-dependent and stationary-phase Arg+ revertants was significantly increased in the dnaQ49 mutant at the non-permissive temperature of 37°C. At this temperature, in contrast to cultures grown at 28°C, SOS functions were dramatically increased. Deletion of the umuDC operon in the dnaQ49 strain led to a 10-fold decrease in the level of Arg+ revertants in cultures grown at 37°C and only to a 2-fold decrease in cultures grown at 28°C. Furthermore, in stationary-phase cultures Pol V influenced spontaneous mutagenesis to a much lesser extent than in growing cultures. Our results indicate that the level of Pol III desintegration, dependent on the temperature of incubation, is more critical for spontaneous mutagenesis in stationary-phase dnaQ49 cells than the presence or absence of Pol V.
Źródło:
Acta Biochimica Polonica; 2004, 51, 3; 683-692
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Properties of Escherichia coli RNA polymerase from a strain devoid of the stringent response alarmone ppGpp
Autorzy:
Szalewska-Pałasz, Agnieszka
Powiązania:
https://bibliotekanauki.pl/articles/1040748.pdf
Data publikacji:
2008
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
RNA polymerase
ppGpp
stringent response
transcription
Opis:
The stringent response alarmone guanosine tetraphosphate (ppGpp) affects transcription from many promoters. ppGpp binds directly to the transcription enzyme of Escherichia coli, RNA polymerase. Analysis of the crystal structure of RNA polymerase with ppGpp suggested that binding of this nucleotide may result in some conformational or post-translational alterations to the enzyme. These changes might affect in vitro performance of the enzyme. Here, a comparison of the in vitro properties of RNA polymerases isolated from wild type and ppGpp-deficient bacteria shows that both enzymes do not differ in i) transcription activity of various promoters (e.g. σ70-rrnB P1, λpL, T7A1), ii) response to ppGpp, iii) promoter-RNA polymerase open complex stability. Thus, it may be concluded that ppGpp present in the bacterial cell prior to purification of the RNA polymerase does not result in the alterations to the enzyme that could be permanent and affect its in vitro transcription capacity.
Źródło:
Acta Biochimica Polonica; 2008, 55, 2; 317-323
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis of glycosylated flavonoids extracted from sweet-cherry stems, as antibacterial agents against pathogenic Escherichia coli isolates
Autorzy:
Aires, Alfredo
Dias, Carla
Carvalho, Rosa
Saavedra, Maria
Powiązania:
https://bibliotekanauki.pl/articles/1038644.pdf
Data publikacji:
2017
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
flavonoids
agro-food wastes
enhanced extraction
antimicrobial agents
pathogenic bacteria
Opis:
The aim of this study was to evaluate the bioactivity of flavonoids extracted from sweet-cherry stems which are often used by a traditional system of medicine to treat gastro-intestinal and urinary tract infections but lacking any consistent scientific evidence; moreover the information about the class of phenolics, their content and the potential bioactivity of such material is very scarce. Thus, in this context, we have set a research study in which we evaluated the profile and content of phenolics extracted from sweet-cherry stems through a conventional (70ºC and 20 min) and ultrasound assisted extraction (40 kHz, room temperature and 20 min). The extracts were phytochemically characterized by using an HPLC-DAD-UV/VIS system and assayed by an in vitro minimum inhibitory concentration (MIC) bioassay against Escherichia coli isolates. Simultaneously, the total antioxidant activities were measured using the 2,2'-azinobis-3-ethylbenzothiazoline-6-sulphonate (ABTS•+) radical cation assay. Our results indicate that sweet-cherry stems have a high content of sakuranetin, ferulic acid, p-coumaric acid, p-coumaroylquinic acid, chlorogenic acid and its isomer neochlorogenic acid. Their average levels were highly affected by the extraction method used (p<0.001). The same trend was observed for total antioxidant activity and MIC values. The extracts produced with ultrasounds presented both, a higher total antioxidant activity and a lower minimum inhibitory concentration. Statistical analyses of our results showed a significant correlation (p<0.01) of total antioxidant activity and minimum inhibitory concentration with phenolics present in the extracts studied. Thus, we can conclude that cherry stems can be further exploited to purify compounds and produce coproducts with enhanced biologically added value for pharmaceutical industry.
Źródło:
Acta Biochimica Polonica; 2017, 64, 2; 265-271
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Modulation of virulence genes by the two-component system PhoP - PhoQ in avian pathogenic Escherichia coli
Autorzy:
Tu, J.
Huang, B.
Zhang, Y.
Xue, T.
Li, S.
Qi, K.
Powiązania:
https://bibliotekanauki.pl/articles/30418.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Opis:
Avian pathogenic Escherichia coli (APEC) infections are a very important problem in the poultry industry. PhoP-PhoQ is a two-component system that regulates virulence genes in APEC. In this study, we constructed strains that lacked the PhoP or PhoQ genes to assess regulation of APEC pathogenicity by the PhoP-PhoQ two-component system. The PhoP mutant strain AE18, PhoQ mutant strain AE19, and PhoP/PhoQ mutant strain AE20 were constructed by the Red homologous recombination method. Swim plates were used to evaluate the motility of the APEC strains, viable bacteria counting was used to assess adhesion and invasion of chick embryo fibroblasts, and Real-Time PCR was used to measure mRNA expression of virulence genes. We first confirmed that AE18, AE19, and AE20 were successfully constructed from the wild-type AE17 strain. AE18, AE19, and AE20 showed significant decreases in motility of 70.97%, 83.87%, and 37.1%, respectively, in comparison with AE17. Moreover, in comparison with AE17, AE18, AE19, and AE20 showed significant decreases of 63.11%, 65.42%, and 30.26%, respectively, in CEF cell adhesion, and significant decreases of 59.83%, 57.82%, and 37.90%, respectively, in CEF cell invasion. In comparison with AE17, transcript levels of sodA, polA, and iss were significantly decreased in AE18, while transcript levels of fimC and iss were significantly decreased in AE19. Our results demonstrate that deletion of PhoP or PhoQ inhibits invasion and adhesion of APEC to CEF cells and significantly reduces APEC virulence by regulating transcription of virulence genes.
Źródło:
Polish Journal of Veterinary Sciences; 2016, 19, 1
1505-1773
Pojawia się w:
Polish Journal of Veterinary Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Expression in Escherichia coli of human ARHGAP6 gene and purification of His-tagged recombinant protein.
Autorzy:
Ochocka, Anna-Maria
Czyżewska, Marzena
Pawełczyk, Tadeusz
Powiązania:
https://bibliotekanauki.pl/articles/1043671.pdf
Data publikacji:
2003
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
His-tag
IbpB
ARHGAP6
IbpA
Opis:
In this report we describe cloning and expression of human Rho GTPase activating protein (ARHGAP6) isoform 4 in Escherichia coli cells as a fusion protein with 6xHis. We cloned the ARHGAP6 cDNA into the bacterial expression vector pPROEX-1. Induction of the 6xHis-ARHGAP6 protein in BL21(DE3) and DH5α cells caused lysis of the cells irrespective of the kind of culture medium used. Successful expression of the fusion protein was obtained in the MC4100Δibp mutant strain lacking the small heat-shock proteins IbpA and IbpB. Reasonable yield was obtained when the cells were cultured in Terrific Broth + 1% glucose medium at 22°C for 16 h. The optimal cell density for expression of soluble 6xHis-ARHGAP6 protein was at A_600 about 0.5. Under these conditions over 90% of the fusion protein was present in a soluble form. The 6xHis-ARHGAP6 protein was purified to near homogeneity by a two step procedure comprising chromatography on Ni-nitrilotriacetate and cation exchange columns. The expression system and purification procedure employed made it possible to obtain 1-2 mg of pure 6xHis-ARHGAP6 protein from 300 ml (1.5 g of cells) of E. coli culture.
Źródło:
Acta Biochimica Polonica; 2003, 50, 1; 239-247
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The DnaK chaperones from the archaeon Methanosarcina mazei and the bacterium Escherichia coli have different substrate specificities
Autorzy:
Żmijewski, Michal
Skórko-Glonek, Joanna
Tanfani, Fabio
Banecki, Bogdan
Kotlarz, Agnieszka
Macario, Alberto
Lipińska, Barbara
Powiązania:
https://bibliotekanauki.pl/articles/1040934.pdf
Data publikacji:
2007
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
archaeal DnaK quaternary structure
archaeal Hsp70(DnaK)
substrate-binding by archaeal DnaK
Opis:
Hsp70 (DnaK) is a highly conserved molecular chaperone present in bacteria, eukaryotes, and some archaea. In a previous work we demonstrated that DnaK from the archaeon Methanosarcina mazei (DnaKMm) and the DnaK from the bacterium Escherichia coli (DnaKEc) were functionally similar when assayed in vitro but DnaKMm failed to substitute for DnaKEc in vivo. Searching for the molecular basis of the observed DnaK species specificity we compared substrate binding by DnaKMm and DnaKEc. DnaKMm showed a lower affinity for the model peptide (a-CALLQSRLLS) compared to DnaKEc. Furthermore, it was unable to negatively regulate the E. coli σ32 transcription factor level under heat shock conditions and poorly bound purified σ32, which is a native substrate of DnaKEc. These observations taken together indicate differences in substrate specificity of archaeal and bacterial DnaKs. Structural modeling of DnaKMm showed some structural differences in the substrate-binding domains of DnaKMm and DnaKEc, which may be responsible, at least partially, for the differences in peptide binding. Size-exclusion chromatography and native gel electrophoresis revealed that DnaKMm was found preferably in high molecular mass oligomeric forms, contrary to DnaKEc. Oligomers of DnaKMm could be dissociated in the presence of ATP and a substrate (peptide) but not ADP, which may suggest that monomer is the active form of DnaKMm.
Źródło:
Acta Biochimica Polonica; 2007, 54, 3; 509-522
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Stan sanitarny wód użytku ekologicznego Staw przy Kaczeńcowej oraz lekooporność bakterii Escherichia coli izolowanych ze zbiornika
Sanitary condition of water of the “Staw przy Kaczeńcowej” ecological area and antimicrobial resistance of escherichia coli isolated from the reservoir
Autorzy:
Wolny-Koładka, K.
Powiązania:
https://bibliotekanauki.pl/articles/339309.pdf
Data publikacji:
2018
Wydawca:
Instytut Technologiczno-Przyrodniczy
Tematy:
Escherichia coli
lekooporność
metoda dyfuzyjno-krążkowa
mikrobiologiczne zanieczyszczenie
wody
użytek ekologiczny
ecological area
disc diffusion method
drug resistance
microbiological
contamination of water
Opis:
Badania miały na celu ocenę stanu mikrobiologicznego wód pobranych z użytku ekologicznego „Staw przy Kaczeńcowej” w Nowej Hucie (Kraków), a także określenie, czy w zbiorniku występują drobnoustroje potencjalnie niebezpieczne z epidemiologicznego punktu widzenia. Dodatkowo z wód „Stawu przy Kaczeńcowej” izolowano bakterie z gatunku E. coli, w celu określenia ich profilu lekooporności. Analizy mikrobiologiczne obejmowały określenie liczebności bakterii mezofilnych, psychrofilnych, bakterii z grupy coli, form kałowych E. coli, a także E. faecalis, C. perfringens, Staphylococcus spp. i Salmonella spp. Próbki wód pobierane były 4 razy w roku (wiosna, lato, jesień, zima) w 5 punktach na terenie zbiornika. Ponadto, w każdym punkcie pomiarowym mierzono temperaturę wody oraz powietrza. Za pomocą metody dyfuzyjno-krążkowej określono wrażliwość szczepów E. coli na powszechnie stosowane antybiotyki. W pobranych próbkach zidentyfikowano wszystkie badane wskaźniki czystości mikrobiologicznej wód, które stanowią potencjalne zagrożenie epidemiologiczne. Wyizolowano 60 szczepów zidentyfikowanych jako E. coli, które najczęściej miały oporność na tikarcylinę i ampicylinę. Mimo że stwierdzono obecność szczepów wielolekoopornych, mechanizmu ESBL (β-laktamazy o rozszerzonym spektrum substratowym) nie wykryto.
This study was aimed to assess the microbiological quality of water in the ecological area „Staw przy Kaczeńcowej” in Nowa Huta (Cracow) as well as to determine whether its waters contain microorganisms potentially dangerous from an epidemiological point of view. In addition, E. coli bacteria were isolated from the water of “Staw przy Kaczeńcowej” to determine their drug resistance profile. Microbiological analyses included the determination of the number of mesophilic and psychrophilic bacteria, coliforms, fecal E. coli, as well as E. faecalis, C. perfringens, Staphylococcus spp. and Salmonella spp. Water samples were collected 4 times per year (spring, summer, autumn, winter) at 5 points within the area of the reservoir. Water and air temperature was measured onsite. Using the disc diffusion method, the sensitivity of E. coli strains to commonly used antibiotics was determined. All analyzed microbiological indicators of poor water quality were found in the analyzed water samples, which may pose a potential epidemiological risk. In addition were isolated 60 strains identified as E. coli, that most commonly had resistance to ticarcillin and ampicillin. Although, multidrug resistant strains have been identified, ESBL (β-lactamases with an extended substrate spectrum) mechanism has not been detected.
Źródło:
Woda-Środowisko-Obszary Wiejskie; 2018, 18, 1; 99-112
1642-8145
Pojawia się w:
Woda-Środowisko-Obszary Wiejskie
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Prevalence of pathogenicity island ETT2 in Escherichia coli isolated from piglets with diarrhea in northeast of China
Autorzy:
Yuan, C.W.
Liu, W.X.
Hou, J.L.
Zhang, L.G.
Wang, G.Q.
Powiązania:
https://bibliotekanauki.pl/articles/2087783.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Escherichia coli
pathogenicity island
ETT2
piglets
diarrhea
Źródło:
Polish Journal of Veterinary Sciences; 2018, 21, 1; 5-12
1505-1773
Pojawia się w:
Polish Journal of Veterinary Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Characterization of the Escherichia coli gene encoding a new member of the short-chain dehydrogenase/reductase (SDR) family
Autorzy:
Sirko, Agnieszka
Węgleńska, Anna
Hryniewicz, Monika
Hulanicka, Danuta
Powiązania:
https://bibliotekanauki.pl/articles/1044977.pdf
Data publikacji:
1997
Wydawca:
Polskie Towarzystwo Biochemiczne
Źródło:
Acta Biochimica Polonica; 1997, 44, 1; 153-157
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of disulfide and sulfhydryl reagents on abortive and productive elongation catalyzed by Escherichia coli RNA polymerase
Autorzy:
Radłowski, Marek
Job, Dominique
Powiązania:
https://bibliotekanauki.pl/articles/1045305.pdf
Data publikacji:
1994
Wydawca:
Polskie Towarzystwo Biochemiczne
Źródło:
Acta Biochimica Polonica; 1994, 41, 4; 415-419
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Development and application of isothermal amplification methods for rapid detection of F4 fimbriae producing Escherichia coli
Autorzy:
Zhao, L.Y.
Niu, J.H.
Gao, X.L.
Liu, C.N.
Liu, S.M.
Jiang, N.
Lv, X.P.
Zheng, S.M.
Powiązania:
https://bibliotekanauki.pl/articles/2087340.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Escherichia coli
F4 fimbriae
isothermal amplification
rapid detection
clinical samples
Źródło:
Polish Journal of Veterinary Sciences; 2020, 23, 1; 143-152
1505-1773
Pojawia się w:
Polish Journal of Veterinary Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Non-random distribution of GATC sequences in regions of promoters stimulated by the SeqA protein of Escherichia coli.
Autorzy:
Strzelczyk, Barbara
Słomińska-Wojewódzka, Monika
Węgrzyn, Grzegorz
Węgrzyn, Alicja
Powiązania:
https://bibliotekanauki.pl/articles/1043365.pdf
Data publikacji:
2003
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
transcription regulation
SeqA protein
promoter sequence
GATC motif
Opis:
The SeqA protein of Escherichia coli is not only the main negative regulator of DNA replication initiation but also a specific transcription factor. It binds to hemimethylated GATC sequences and, with somewhat different specificity, to fully methylated GATC regions. Recently, a microarray analysis was reported, in which transcriptomes of wild-type and ΔseqA strains were compared. Although in the seqA mutant the levels of some transcripts were significantly decreased while certain transcripts were evidently more abundant relative to wild-type bacteria, no correlation between the presence of GATC motifs in promoter sequences and transcription activity was found. However, here we show that when larger DNA fragments, encompassing positions from -250 to +250 relative to the transcription start site, are analyzed, some common features of GATC distribution near the promoters activated by SeqA can be demonstrated. Nevertheless, it seems that the GATC pattern is not the only determinant of SeqA-dependence of promoter activity.
Źródło:
Acta Biochimica Polonica; 2003, 50, 4; 941-945
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The use of infrared spectroscopy and artificial neural networks for detection of uropathogenic Escherichia coli strains susceptibility to cephalothin
Autorzy:
Lechowicz, Łukasz
Urbaniak, Mariusz
Adamus-Białek, Wioletta
Kaca, Wiesław
Powiązania:
https://bibliotekanauki.pl/articles/1039472.pdf
Data publikacji:
2013
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
infrared spectroscopy
artificial neural network
uropathogenic Escherichia coli
antibiotic resistance
Opis:
Background & Aims: Infrared spectroscopy is an increasingly common method for bacterial strains' testing. For the analysis of bacterial IR spectra, advanced mathematical methods such as artificial neural networks must be used. The combination of these two methods has been used previously to analyze taxonomic affiliation of bacteria. The aim of this study was the classification of Escherichia coli strains in terms of susceptibility/resistance to cephalothin on the basis of their infrared spectra. The infrared spectra of 109 uropathogenic E. coli strains were measured. These data are used for classification of E. coli strains by using designed artificial neural networks. Results: The most efficient artificial neural networks classify the E. coli sensitive/resistant strains with an error of 5%. Conclusions: Bacteria can be classified in terms of their antibiotic susceptibility by using infrared spectroscopy and artificial neural networks.
Źródło:
Acta Biochimica Polonica; 2013, 60, 4; 713-718
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Zastosowanie immunofluorescencji w mikrobiologii wody na przykładzie wybranych chorobotwórczych szczepów Escherichia coli. Cz.II. Badania z zakażaną wodą naturalną
The use of immunofluorescence in water microbiology as exemplified by selected strains of enteropathogenic Escherichia coli Part.II. Studies on infected natural water
Autorzy:
Danielsson, D.
Zieminska, S.
Powiązania:
https://bibliotekanauki.pl/articles/871783.pdf
Data publikacji:
1973
Wydawca:
Narodowy Instytut Zdrowia Publicznego. Państwowy Zakład Higieny
Tematy:
mikrobiologia wod
immunofluorescencja
szczepy chorobotworcze
Escherichia coli
woda
badania naukowe
zanieczyszczenia wod
Źródło:
Roczniki Państwowego Zakładu Higieny; 1973, 24, 3
0035-7715
Pojawia się w:
Roczniki Państwowego Zakładu Higieny
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Reversion of argE3 to Arg+ in Escherichia coli AB1157 -an informative bacterial system for mutation detection
Autorzy:
Sikora, Anna
Grzesiuk, Elżbieta
Powiązania:
https://bibliotekanauki.pl/articles/1040308.pdf
Data publikacji:
2010
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
mutations
Arg+ revertants
Escherichia coli K12
prototrophy
T4 phages
suppressor tRNA
Opis:
This review concerns reversion of the argE3 (ochre) nonsense mutation to prototrophy in E. coli AB1157 strain as an informative system for mutation detection. Strain AB1157 bears the argE3 (ochre), hisG4 (ochre) and thr-1 (amber) mutations, and the supE44 amber suppressor on its chromosome. The Arg+ phenotype can be restored by (i) any base substitution at the argE3 site that changes the nonsense UAA codon to any sense nucleotide triplet or to UAG recognized by the supE44 amber suppressor, or (ii) suppressor mutations enabling the reading of the UAA nonsense codon. The argE3 → Arg+ reversion-based system enables (i) determination of the spontaneous or induced mutation level; (ii) determination of base substitutions (suppressor analysis); (iii) examination of transcription-coupled repair (TCR) since targets for DNA damage are situated on the transcribed or coding strand of DNA; (iv) detection of mutations resulting from single stranded DNA damage. This review focuses on studies carried out since the early 1990s till now with the application of the AB1157-based mutation detection system. Recently, the system has been used to obtain new data on the processes of methyl methanesulfonate-induced mutagenesis and DNA repair in E. coli alkB- mutants.
Źródło:
Acta Biochimica Polonica; 2010, 57, 4; 479-485
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A freeze-thaw method for disintegration of Escherichia coli cells producing T7 lysozyme used in pBAD expression systems
Autorzy:
Wanarska, Marta
Hildebrandt, Piotr
Kur, Józef
Powiązania:
https://bibliotekanauki.pl/articles/1041062.pdf
Data publikacji:
2007
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
pBAD expression systems
disintegration
T7 lysozyme
Opis:
The pLysN plasmid containing the T7 lysozyme gene under control of the lac promoter was constructed to facilitate cell disintegration after expression of recombinant proteins in arabinose-induced expression systems. The usefulness of this plasmid was tested in Escherichia coli TOP10 and E. coli LMG194 cells carrying pBADMHADgeSSB plasmid containing Deinococcus geothermalis SSB protein gene under control of the araBAD promoter. The results showed that low-level expression of T7 lysozyme did not interfere with the target SSB protein production, and that the freezing-thawing treatment was sufficient for disruption of the E. coli cells producing low amounts of T7 lysozyme.
Źródło:
Acta Biochimica Polonica; 2007, 54, 3; 671-672
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Szacowanie wplywu warunkow wedzenia surowych wyrobow miesnych na mozliwosc wzrostu Listeria monocytogenes i Escherichia coli O157:H7
Predicting the effect of smoking conditions on the growth of Listeria monocytogenes and Escherichia coli O157:H7 in raw meat products
Autorzy:
Kaczmarek, A
Zabielski, J
Zielonka, P
Powiązania:
https://bibliotekanauki.pl/articles/826570.pdf
Data publikacji:
2005
Wydawca:
Polskie Towarzystwo Technologów Żywności
Tematy:
przetwory miesne wedzone
przetwory miesne surowe
wedzenie
warunki wedzenia
zawartosc azotanow
zawartosc soli
pH
czas wedzenia
stabilnosc mikrobiologiczna
Escherichia coli
Listeria monocytogenes
bakterie
wyrozniki fizykochemiczne
smoked meat product
raw meat product
smoking process
nitrate content
salt content
microbial stability
bacteria
physicochemical feature
Opis:
Celem pracy była prognoza wpływu warunków wędzenia trzech gatunków surowych wyrobów mięsnych na możliwość wzrostu bakterii Listeria monocytogenes i Escherichia coli O157:H7. Badania przeprowadzono w wybranym zakładzie mięsnym, w rzeczywistych warunkach produkcji handlowej. Obiekt badawczy stanowiły wyroby z 5 partii produkcyjnych schabu surowego, frankfurterek oraz kiełbasy polskiej surowej. W produktach wędzonych oznaczano zawartość: soli, azotanów(III), pH oraz czas wędzenia w zakresie temp. 30–37°C. Prognozy wzrostu wybranych patogenów, z uwzględnieniem wyników przeprowadzonych oznaczeń, obliczono za pomocą programu Pathogen Modeling Program 6,0. Wykazano bardzo dużą zmienność zawartości azotanów(III) (V = 23,63–59,76%), soli (V = 10,82–17,78%) oraz rzeczywistych okresów obróbki wędzarniczej (V = 35,1–39,1%) poszczególnych partii produkcyjnych badanych wyrobów. W konsekwencji, obliczone prognozy okresów stabilności mikrobiologicznej Escherichia coli O157:H7 w poszczególnych partiach produkcyjnych schabu surowego charakteryzowały się znacznym zróżnicowaniem (V = 9–95%). Zastosowane warunki wędzenia spowodowały, że w przypadku kiełbasy polskiej oraz frankfurterek prawdopodobne było zakończenie okresu lag-fazy Escherichia coli O157:H7 jeszcze w czasie tego zabiegu.
The objective of the study was to predict the effect of smoking conditions applied to smoke three types of raw meat products on the potential for Listeria monocytogenes and Escherichia coli O157:H7 to grow in those products. The study was performed in a selected meat processing plant, under real production conditions as existing during any regular, commercial production process carried out in this plant. The study target comprised five batches of the following products being produced: a raw pork loin, Frankfurter sausages, and a raw soft ‘Polish’ sausage. The following parameters of products being smoked were determined: contents of salts and nitrates(III), pH, and the smoking process temperatures within a range from 30℃ to 37℃ . The pathogen growth levels being predicted were calculated using a Pathogen Modelling Software, version 6.0; the calculations performed included the parameters as determined above. With regard to individual production batches of products under analysis, there were stated very high variations among the following parameters characterizing the same product type in all 5 batches: contents of nitrates (III) (V = 23.63–59.6%), contents of salts (V = 10.82–17.78%), and real smoking times (V = 35.1–39.1%). Consequently, there were high differences among predicted periods of microbial stability of Escherichia coli O157:H7 calculated for each individual production batch of raw pork loin (V = 9–95%). The smoking conditions applied in this plant caused that, in the case of the Polish sausages and Frankfurter sausages, it was possible for the lag-phase of Escherichia coli O157:H7 to end prior to the completion of the entire smoking process.
Źródło:
Żywność Nauka Technologia Jakość; 2005, 12, 1; 18-26
1425-6959
Pojawia się w:
Żywność Nauka Technologia Jakość
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Wpływ temperatury na przeżywalność, właściwości fenotypowe i antygenowe szczepów Escherichia coli O157 wyizolowanych z wody i materiału klinicznego
The influence of temperature on survival, phenotype and antygen properties of Escherichia coli O157 strains isolated from water and clinical material
Autorzy:
Michalska-Szymaszek, M.
Powiązania:
https://bibliotekanauki.pl/articles/874600.pdf
Data publikacji:
2010
Wydawca:
Narodowy Instytut Zdrowia Publicznego. Państwowy Zakład Higieny
Opis:
W badaniach określono przeżywalność szczepów E. coli O157 (SF-fermentujących sorbitol i NSF – nie fermentujących sorbitolu) w sterylnych próbkach wody powierzchniowej. Próbki wody były dodatkowo zakażone innymi bakteriami stanowiącymi mikroflorę towarzyszącą. Próbki wody były badane w temperaturze 5ºC i 25ºC w stabilnych warunkach laboratoryjnych i w warunkach środowiskowych. Wyniki badań wykazały zmiany właściwości fenotypowych i antygenowych badanych szczepów. Zmiany te utrudniają identyfikację i izolację E. coli O157 z wód powierzchniowych zawierających mieszaną mikroflorę towarzyszącą. Szczepy E. coli O157 obecne w wodzie stanowią zagrożenie dla człowieka kąpiącego się w tych wodach. Ryzyko dla zdrowia wynika z obecności czynników wirulencji w komórkach tych bakterii, które po pewnym czasie przebywania w wodzie są jednak częściowo tracone.
In this research I evaluated E. coli O157 strains’ ( SF-sorbitolfermenting and NSF – non sorbitolfermenting) ability to survive in samples of surface waters. These samples were additionally contaminated with other strains, used as background microflora. These water samples were stored in the temperature 5ºC i 25ºC in laboratory and environmental conditions. The results of the research show changes of phenotype and antigen properties of E. coli O157 strains during research. These changes make it difficult to isolate E. coli O157 strains from natural water with numerous background microflora. These strains in surface water are threat for humans, who swim such waters in the summer. The threat results from toxic virulent factors staying for a short period of time in bacterial cells, which are lost in water.
Źródło:
Roczniki Państwowego Zakładu Higieny; 2010, 61, 2
0035-7715
Pojawia się w:
Roczniki Państwowego Zakładu Higieny
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Maillard neoglycans as inhibitors for in vitro adhesion of F4+ enterotoxigenic Escherichia coli to piglet intestinal cells
Autorzy:
Sarabia-Sainz, Héctor
Mata Haro, Verónica
Sarabia Sainz, José
Vázquez-Moreno, Luz
Montfort, Gabriela
Powiązania:
https://bibliotekanauki.pl/articles/1038559.pdf
Data publikacji:
2017
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
Albumin glycation
biorecognition
anti-adhesion
E. coli
Opis:
Adhesion of enterotoxigenic (ETEC) E. coli to host intestinal cells is mediated by lectin-like fimbriae that bind to specific glycan moieties on the surfaces of enterocytes. To prevent in vitro binding of E. coli F4 fimbriae (F4 ETEC+) to piglet enterocytes, neoglycans were synthesized by the Maillard reaction conjugating lactose (Lac), galacto-oligosaccharides (GOS) or chitin oligosaccharides (Ochit) to porcine serum albumin (PSA). Neoglycans were characterized by SDS-PAGE, intrinsic tryptophan fluorescence and recognition by plant lectins, as well as by F4 ETEC variants. Electrophoretic patterns suggested the binding to PSA of 63, 13 and 2 molecules of Lac, GOS and Ochit, respectively. All neoglycans displayed quenching of tryptophan fluorescence consistent with the degree of glycation estimated by SDS-PAGE. Plant lectins recognized the neoglycans according to their specificity, whereas antigenic variants of F4 ETEC (ab, ac and ad) recognized PSA-Ochit and PSA-Lac with higher affinity than that for GOS. Neoglycans partially hindered the in vitro binding of F4+ ETEC to piglet enterocytes in a dose-dependent manner. The most effective blocking was observed with PSA-Lac that partially inhibited the adhesion of bacteria to enterocytes in a dose dependent manner, as quantified by flow cytometry. Increased production of the cytokines IL-6 and TNF-α was observed in response to F4+ ETEC infection of enterocytes and production was reduced in the presence of PSA-Ochit and PSA-GOS. These results suggest that neoglycans synthesized by the Maillard reaction could be useful in the prophylaxis of diarrhea in piglets.
Źródło:
Acta Biochimica Polonica; 2017, 64, 4; 679-686
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On the mode of integration of the thylakoid membrane protein cytochrome b6 into cytoplasmic membrane of Escherichia coli
Autorzy:
Króliczewski, Jaroslaw
Gubernator, Beata
Rögner, Matthias
Szczepaniak, Andrzej
Powiązania:
https://bibliotekanauki.pl/articles/1039882.pdf
Data publikacji:
2011
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
membrane protein
signal sequence
integration/translocation
cytochrome b6
Opis:
In the stroma compartment, several pathways are used for integration/translocation of chloroplast proteins into or across the thylakoid membrane. In this study we investigated the mode of incorporation of the chloroplast-encoded cytochrome b6 into the bacterial membrane. Cytochrome b6 naturally comprises of four transmembrane helices (A,B,C,D) and contains two b-type hemes. In the present study, mature cytochrome b6 or constructed deletion mutants of cytochrome were expressed in E. coli cells. The membrane insertion of cytochrome b6 in this bacterial model system requires an artificially added presequence that directs the protein to use an E. coli membrane-insertion pathway. This could be accomplished by fusion to maltose-binding protein (MBP) or to the bacterial Sec-dependent signal peptide (SSpelB). The integration of mature cytochrome b6 into the bacterial cytoplasmic membrane by the Sec pathway has been reported previously by our group (Kroliczewski et al., 2005, Biochemistry, 44: 7570). The results presented here show that cytochrome b6 devoid of the first helix A can be inserted into the membrane, as can the entire ABCD. On the other hand, the construct devoid of helices A and B is translocated through the membrane into the periplasm without any effective insertion. This suggests the importance of the membrane-anchoring sequences that are likely to be present in only the A and B part, and it is consistent with the results of computational prediction which did not identify any membrane-anchoring sequences for the C or D helices. We also show that the incorporation of hemes into the truncated form of cytochrome b6 is possible, as long as the B and D helices bearing axial ligands to heme are present.
Źródło:
Acta Biochimica Polonica; 2011, 58, 3; 335-343
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Expression of three diadinoxanthin de-epoxidase genes of Phaeodacylum tricornutum in Escherichia coli Origami b and BL21 strain
Autorzy:
Bojko, Monika
Olchawa-Pajor, Monika
Tuleja, Urszula
Kuczyńska, Paulina
Strzałka, Wojciech
Latowski, Dariusz
Strzałka, Kazimierz
Powiązania:
https://bibliotekanauki.pl/articles/1039507.pdf
Data publikacji:
2013
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
diadinoxanthin cycle
marine diatoms
violaxanthin
de-epoxidation
Opis:
In the diadinoxanthin cycle the epoxy group is removed from diadinoxanthin and diatoxanthin is created. This conversion takes place e.g. in diatoms with the involvement of the enzyme diadinoxanthin de-epoxidase. In one of the diatom species, Phaeodactylum tricornutum (CCAP 1055/1 strain with genome sequenced) three de-epoxidase genes (PtVDE, PtVDL1, PtVDL2) have been identified, but only one of them (PtVDE) corresponds to violaxanthin de-epoxidase, an enzyme which is commonly found in higher plants. In these studies, the expression of two de-epoxidase genes of another Phaeodactylum tricornutum strain (UTEX 646), which is commonly used in diatom studies, were obtained in Origami b and BL21 E. coli strains. The molecular masses of the mature proteins are about 49 kDa and 60 kDa, respectively, for VDE and VDL2. Both enzymes are active with violaxanthin as a substrate.
Źródło:
Acta Biochimica Polonica; 2013, 60, 4; 857-860
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Overexpression of genes involved in phytochelatin biosynthesis in Escherichia coli: effects on growth, cadmium accumulation and thiol level.
Autorzy:
Wawrzyńska, Anna
Wawrzyński, Adam
Gaganidze, Dali
Kopera, Edyta
Piątek, Katarzyna
Bal, Wojciech
Sirko, Agnieszka
Powiązania:
https://bibliotekanauki.pl/articles/1041468.pdf
Data publikacji:
2005
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
cadmium
thiols
phytochelatin
glutathione
Opis:
In Escherichia coli, heterologous production of Schizosaccharomyces pombe phytochelatin synthase (PCS) along with overproduction of E. coli serine acetyltransferase (SAT) and γ-glutamylcysteine synthase (γECS) was achieved and resulted in the accumulation of phytochelatins in bacterial cells. Overproduction of either γECS alone or simultaneous production of all three proteins in bacterial cells were accompanied by reduced growth rate in liquid cultures. Interestingly, bacteria overproducing either γECS or both SAT and γECS (with elevated level of γ-glutamylcysteine but not of phytochelatins) were able to accumulate more cadmium per dry weight than the control. However, the most efficient cadmium accumulation was observed in bacteria with elevated levels of all three proteins: SAT, γECS and PCS. Therefore, "pushing" the entire pathway might be the most promising approach in modification of bacteria for potential bioremediation purposes because the level of intermediates, cysteine and glutathione, can limit the rate of production of phytochelatins. However, in such bacteria other metabolic process might become limiting for efficient growth.
Źródło:
Acta Biochimica Polonica; 2005, 52, 1; 109-116
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Organic bacteriostatic material
Autorzy:
Flak, Tomasz
Paluch, Jarosław
Gabor, Jadwiga
Okła, Hubert
Stanula, Arkadiusz
Markowski, Jarosław
Plich, Jan
Swinarew, Andrzej S.
Powiązania:
https://bibliotekanauki.pl/articles/1844975.pdf
Data publikacji:
2020
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Polskie Towarzystwo Biominerałów
Tematy:
bacteriostatic
rhodamine
polymer
Escherichia Coli
Opis:
The use of antibiotics to treat bacterial infections is becoming less and less effective year by year due to the increasing resistance of bacteria. The microbial evolutionarily acquired resistance to antibiotics increases the threat to man’s life due to difficulties regarding effective therapies to fight infections. Therefore, apart from treatment, it is necessary to introduce appropriate prophylaxis which limits the multiplication of bacterial colonies on everyday use objects. Due to the antibiotic resistance phenomenon, it is important to find a new material with antibacterial properties for FDM 3D printing in medical applications. The work contains research on a new chemical compound used as an additive to thermoplastics. The rhodamine derivative was synthesized via the 4-diphenylaminobenzaldehyde reaction with 1.3-indendione in a boiling mixture of EtOH/H2SO4. The obtained chemical compound was used as a bacteriostatic modifier of the polycarbonate (PC) properties, as such a modification enables application e.g. for medical device housings or for surfaces frequently touched by people. The modifier and the commercially available polymer were compounded with a high-temperature screw extruder and a filament for FDM 3D printer was created. The modified polymer revealed antibacterial properties relative to Escherichia coli and good thermal stability during the processing.
Źródło:
Engineering of Biomaterials; 2020, 23, 155; 17-21
1429-7248
Pojawia się w:
Engineering of Biomaterials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Expression of bovine leukemia virus protein p24 in Escherichia coli and its use in the immunoblotting assay.
Autorzy:
Bicka, Leokadia
Kuźmak, Jacek
Kozaczyńska, Bożena
Płucienniczak, Andrzej
Skorupska, Anna
Powiązania:
https://bibliotekanauki.pl/articles/1044191.pdf
Data publikacji:
2001
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
bovine leukemia virus
fusion protein p24
immunoblotting assay
gag gene cloning
Opis:
The gag gene encoded protein, p24 of bovine leukemia virus (BLV), was cloned and expressed as thioredoxin-6xHis-p24 protein in Escherichia coli. The bacterial cells carrying plasmid pT7THis-p24 expressed the protein of 38 kDa that was detected by immunoblotting analysis using anti-p24 monoclonal antibodies and sera from BLV infected cattle and sheep. The purified p24 fusion protein was shown to be sensitive and specific for detection of BLV antibodies in the infected cattle.
Źródło:
Acta Biochimica Polonica; 2001, 48, 1; 227-232
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-100 z 209

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