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Tytuł:
Enzymatic oxidation of phthalazine with guinea pig liver aldehyde oxidase and liver slices: inhibition by isovanillin
Autorzy:
Panoutsopoulos, Georgios
Beedham, Christine
Powiązania:
https://bibliotekanauki.pl/articles/1041506.pdf
Data publikacji:
2004
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
xanthine oxidase
phthalazine
aldehyde oxidase
liver slices
disulfiram
isovanillin
allopurinol
Opis:
The enzymes aldehyde oxidase and xanthine oxidase catalyze the oxidation of a wide range of N-heterocycles and aldehydes. These enzymes are widely known for their role in the metabolism of N-heterocyclic xenobiotics where they provide a protective barrier by aiding in the detoxification of ingested nitrogen-containing heterocycles. Isovanillin has been shown to inhibit the metabolism of aromatic aldehydes by aldehyde oxidase, but its inhibition towards the heterocyclic compounds has not been studied. The present investigation examines the oxidation of phthalazine in the absence and in the presence of the inhibitor isovanillin by partially purified aldehyde oxidase from guinea pig liver. In addition, the interaction of phthalazine with freshly prepared guinea pig liver slices, both in the absence and presence of specific inhibitors of several liver oxidizing enzymes, was investigated. Aldehyde oxidase rapidly converted phthalazine into 1-phthalazinone, which was completely inhibited in the presence of isovanillin (a specific inhibitor of aldehyde oxidase). In freshly prepared liver slices, phthalazine was also rapidly converted to 1-phthalazinone. The formation of 1-phthalazinone was completely inhibited by isovanillin, whereas disulfiram (a specific inhibitor of aldehyde dehydrogenase) only inhibited 1-phthalazinone formation by 24% and allopurinol (a specific inhibitor of xanthine oxidase) had little effect. Therefore, isovanillin has been proved as an inhibitor of the metabolism of heterocyclic substrates, such as phthalazine, by guinea pig liver aldehyde oxidase, since it had not been tested before. Thus it would appear from the inhibitor results that aldehyde oxidase is the predominant enzyme in the oxidation of phthalazine to 1-phthalazinone in freshly prepared guinea pig liver slices, whereas xanthine oxidase only contributes to a small extent and aldehyde dehydrogenase does not take any part.
Źródło:
Acta Biochimica Polonica; 2004, 51, 4; 943-951
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Kinetics and specificity of guinea pig liver aldehyde oxidase and bovine milk xanthine oxidase towards substituted benzaldehydes.
Autorzy:
Panoutsopoulos, Georgios
Beedham, Christine
Powiązania:
https://bibliotekanauki.pl/articles/1041542.pdf
Data publikacji:
2004
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
xanthine oxidase
dopamine
benzaldehydes
aldehyde oxidase
protocatechuic aldehyde
isovanillin
Opis:
Molybdenum-containing enzymes, aldehyde oxidase and xanthine oxidase, are important in the oxidation of N-heterocyclic xenobiotics. However, the role of these enzymes in the oxidation of drug-derived aldehydes has not been established. The present investigation describes the interaction of eleven structurally related benzaldehydes with guinea pig liver aldehyde oxidase and bovine milk xanthine oxidase, since they have similar substrate specificity to human molybdenum hydroxylases. The compounds under test included mono-hydroxy and mono-methoxy benzaldehydes as well as 3,4-dihydroxy-, 3-hydroxy-4-methoxy-, 4-hydroxy-3-methoxy-, and 3,4-dimethoxy-benzaldehydes. In addition, various amines and catechols were tested with the molybdenum hydroxylases as inhibitors of benzaldehyde oxidation. The kinetic constants have shown that hydroxy-, and methoxy-benzaldehydes are excellent substrates for aldehyde oxidase (Km values 5×10-6 M to 1×10-5 M) with lower affinities for xanthine oxidase (Km values around 10-4 M). Therefore, aldehyde oxidase activity may be a significant factor in the oxidation of the aromatic aldehydes generated from amines and alkyl benzenes during drug metabolism. Compounds with a 3-methoxy group showed relatively high Vmax values with aldehyde oxidase, whereas the presence of a 3-hydroxy group resulted in minimal Vmax values or no reaction. In addition, amines acted as weak inhibitors, whereas catechols had a more pronounced inhibitory effect on the aldehyde oxidase activity. It is therefore possible that aldehyde oxidase may be critical in the oxidation of the analogous phenylacetaldehydes derived from dopamine and noradrenaline.
Źródło:
Acta Biochimica Polonica; 2004, 51, 3; 649-663
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The age of shelterbelts as a factor determining of enzymes activity in the agricultural landscape
Wiek zadrzewienia jako czynnik determinujący aktywność enzymów w krajobrazie rolniczym
Autorzy:
Wojciech, Szajdak
Meysner, Teresa
Gaca, Wioletta
Styła, Katarzyna
Szczepański, Marek
Powiązania:
https://bibliotekanauki.pl/articles/126159.pdf
Data publikacji:
2019
Wydawca:
Towarzystwo Chemii i Inżynierii Ekologicznej
Tematy:
shelterbelts
xanthine oxidase activity
urate oxidase activity
phenol oxidase activity
zadrzewienia
aktywność oksydazy ksantynowej
aktywność oksydazy moczanowej
aktywność oksydazy fenolowej
Opis:
Shelterbelts belong to the stable elements in the agricultural landscape which reduce very successfully the concentrations of many chemical compounds migrating with ground water, restrain the erosion and regulate water regime in soils. The investigations were conducted in General Dezydery Chlapowski Landscape Park (West Polish Lowland). For purpose of this experiment three shelterbelts and adjoining cultivated fields were selected. Two of them were planted 200 years ago. The dominant species in the first shelterbelts is Robinia pseudacacia and the second one includes of Crataegus monogyna. The third - new shelterbelt was planted in 1993 and consists of several species of plants. An activity of xanthine, urate, and phenol oxidase was investigated. The obtained results have revealed that annual mean activity of xanthine, urate, and phenol oxidase was statistically significant higher in soils under Robinia pseudacacia (6.42, 13.23, 14.22 μmol · h–1 · g–1, respectively), Crataegus monogyna (4.21, 7.02, 12.79 μmol · h–1 · g–1, respectively) than in the soil under new shelterbelt (2.14, 2.15, 8.05 μmol · h–1 · g–1, respectively) and adjoining cultivated fields. The study was to investigate the influence of the age of shelterbelts on the activity of xanthine, urate, and phenol oxidase.
Zadrzewienia należą do stabilnych elementów krajobrazu rolniczego, które skutecznie redukują stężenia wielu biogenów migrujących z wodą gruntową, ograniczają erozję i regulują reżim wodny w glebie. Funkcje, jakie spełniają zadrzewienia w krajobrazie rolniczym, są ważne ze względu na zrównoważony rozwój obszarów wiejskich. Badania prowadzono w Parku Krajobrazowym im. gen. Dezyderego Chłapowskiego w Turwi (województwo wielkopolskie). Próbki gleb pobierano pod trzema zadrzewieniami różniącymi się wiekiem i składem gatunkowym drzew oraz na przyległych polach uprawnych. Dwa z nich powstały około 200 lat temu. W skład gatunkowy pierwszego wchodzi Robinia pseudacacia, natomiast drugiego Crataegus monogyna. Trzecie, nowe wielogatunkowe zadrzewienie powstało w 1993 roku. W glebach oznaczono aktywność oksydazy ksantynowej, moczanowej i fenolowej. Badania wykazały, że średnia roczna aktywność oznaczonych enzymów była statystycznie istotnie wyższa i wynosiła odpowiednio w glebach pod zdrzewieniem robiniowym 6,42, 13,23, 14,22 μmol · h–1 · g–1, pod zadrzewieniem głogowym 4,21, 7,02, 12,79 μmol · h–1 · g–1 niż pod nowym zadrzewieniem 2,14, 2,15, 8,05 μmol · h–1 · g–1 i na przyległych polach uprawnych. Stwierdzono wpływ wieku zadrzewień na aktywność oksydazy ksantynowej, moczanowej i fenolowej.
Źródło:
Proceedings of ECOpole; 2019, 13, 1-2; 53-67
1898-617X
2084-4557
Pojawia się w:
Proceedings of ECOpole
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Polyphenol oxidase from wheat bran is a serpin
Autorzy:
Yamasaki, Yoshiki
Konno, Haruyoshi
Noda, Kazuhiko
Powiązania:
https://bibliotekanauki.pl/articles/1040750.pdf
Data publikacji:
2008
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
polyphenol oxidase
serpin
wheat bran
Opis:
Polyphenol oxidase (PPO; EC 1.10.3.2) was isolated from wheat bran by a procedure that included ammonium sulfate fractionation, batch adsorption by DEAE-cellulofine, CM-cellulofine column chromatography, DEAE-cellulofine column chromatography, preparative isoelectric focusing, adsorption on the membrane of a Vivapure Q Maxi H spin column, and heat treatment. These procedures led to 150-fold purification with 4.2% recovery. The PPO was homogeneous by SDS/PAGE. The relative molecular weight of the PPO was estimated to be 37000 based on its mobility in SDS/PAGE. The isoelectric point of the PPO was 4.4. The Km values of the PPO for caffeic acid, chlorogenic acid, pyrocatechol, 4-methyl catechol and l-DOPA as substrates were 0.077, 0.198, 1.176, 1.667 and 4.545 mM. The PPO was strongly inhibited by tropolone. The Ki value for tropolone is 2.2 × 10-7 M. The sequence of the 15 N-terminal amino-acid residues was determined to be ATDVRLSIAHQTRFA, which was identical to those of serpin from Triticum aestivum and protein Z from Hordeum vulgare. The PPO strongly inhibited the activity of trypsin, which is an enzyme of serine proteases; 50% inhibition was observed with 1.5 × 10-7 M PPO. The Ki value for PPO is 2.3 × 10-8 M. The wheat bran PPO should be a very important protein for protecting wheat against disease, virus, insect and herbivore damages by both the activities of PPO and protease inhibitor.
Źródło:
Acta Biochimica Polonica; 2008, 55, 2; 325-328
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A possible involvement of plasma membrane NAD(P)H oxidase in the switch mechanism of the cell death mode from apoptosis to necrosis in menadione-induced cell injury.
Autorzy:
Niemczyk, Edyta
Majczak, Anna
Hallmann, Anna
Kędzior, Jakub
Woźniak, Michał
Wakabayashi, Takashi
Powiązania:
https://bibliotekanauki.pl/articles/1041516.pdf
Data publikacji:
2004
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
menadione
NADPH oxidase
necrosis
superoxide
apoptosis
Opis:
The effects of inhibitors of plasma membrane NADPH oxidase on menadione-induced cell injury processes were studied using human osteosarcoma 143B cells. The intracellular level of superoxide in the cells treated with menadione for 6 h reached a maximum followed by an abrupt decrease. The population of apoptotic cells detected by Annexin V and propidium iodide double staining also reached its maximum at 6 h of menadione-treatment while that of necrotic cells increased continuously reaching 90% of the total population at 9 h of the treatment. Pretreatment of the cells with inhibitors of NADPH oxidase, including diphenyliodonium chloride, apocynin, N-vanillylnonanamide and staurosporine was effective in lowering the menadione-induced elevations of superoxide, and also in the suppression of the switch of the cell death mode from apoptosis to necrosis in menadione-treated cells except for the case of staurosporine. These results strongly suggest that superoxide generated by NADPH oxidase, besides that generated by the mitochondria, may contribute to the remarkable increase in the intracellular level of superoxide in the cells treated with menadione for 6 h resulting in the switch from apoptosis to necrosis, although a direct evidence of the presence of active and inactive forms of NADPH oxidase in control and menadione-treated 143B cells is lacking at present.
Źródło:
Acta Biochimica Polonica; 2004, 51, 4; 1015-1022
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Peroxidase and IAA oxidase activities during sink development in cotton seed.
Autorzy:
Rabadia, Vraj
Thaker, Vrinda
Singh, YeshDev
Powiązania:
https://bibliotekanauki.pl/articles/2199024.pdf
Data publikacji:
2006-06-22
Wydawca:
Instytut Hodowli i Aklimatyzacji Roślin
Tematy:
cotton
IAA oxidase
peroxidase
seed development
Opis:
Seeds of the three cotton genotypes, H-6 and H-4 (Gossypium hirsutum),and V797 (G. herbaceum) for their growth variations in IAA oxidase and peroxidase activities. The three genotypes varied in their final seed weight. The peroxidase analysis was done with four different hydrogen donors. Though the trends in peroxidase activitywere almost similar in the three genotypes, there was variation with different hydrogen donors. These was an inverse correlation between Cytoplasmic peroxidase and Wall bound peroxidase activity and rate of water uptake of the seed. The peroxidase activity showed up increasing levels only after the rate of water uptake decreased. However, IAA oxidase activity did not show any discernible trend with water content. The role of cytoplasmic and wall bound peroxidase in seed development is discussed in detail    
Źródło:
Plant Breeding and Seed Science; 2006, 53; 27-36
1429-3862
2083-599X
Pojawia się w:
Plant Breeding and Seed Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The role of alternative oxidase in hypoxic metabolism of nitric oxide
Autorzy:
Igamberdiev, A.
Shah, J.
Cochrane, D.
Gupta, K.
Vanlerberghe, G.
Powiązania:
https://bibliotekanauki.pl/articles/81011.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
conference
alternative oxidase
cytochrome C oxidase
nitric oxide
metabolism
hypoxia
gene expression
oxygen condition
Źródło:
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology; 2013, 94, 2
0860-7796
Pojawia się w:
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Oxalic acid degradation by a novel fungal oxalate oxidase from Abortiporus biennis
Autorzy:
Grąz, Marcin
Rachwał, Kamila
Zan, Radosław
Jarosz-Wilkołazka, Anna
Powiązania:
https://bibliotekanauki.pl/articles/1038790.pdf
Data publikacji:
2016
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
oxalate oxidase
oxalic acid
Abortiporus biennis
Opis:
Oxalate oxidase was identified in mycelial extracts of a basidiomycete Abortiporus biennis strain. Intracellular enzyme activity was detected only after prior lowering of the pH value of the fungal cultures by using oxalic or hydrochloric acids. This enzyme was purified using size exclusion chromatography (Sephadex G-25) and ion-exchange chromatography (DEAE-Sepharose). This enzyme exhibited optimum activity at pH 2 when incubated at 40°C, and the optimum temperature was established at 60°C. Among the tested organic acids, this enzyme exhibited specificity only towards oxalic acid. Molecular mass was calculated as 58 kDa. The values of Km for oxalate and Vmax for the enzyme reaction were 0.015 M and 30 mmol min-1, respectively.
Źródło:
Acta Biochimica Polonica; 2016, 63, 3; 595-600
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
In vivo and in vitro activity of 1-aminocyclopropane-1-carboxylic acid oxidase in germinating seeds of China aster (Callistephus chinensis Nees)
Autorzy:
Chojnowski, M.
Skorupinska, A.
Powiązania:
https://bibliotekanauki.pl/articles/1078232.pdf
Data publikacji:
2020
Wydawca:
Instytut Ogrodnictwa
Tematy:
1-amino-cyclopropane-1-carboxylic acid oxidase
Callistephus chinensis
China aster
germinating seed
protein determination
oxidase activity
Opis:
The activity of 1-aminocyclopropane-1-carboxylic acid oxidase (ACO; EC 1.4.3.3) in germinating seeds of Callistephus chinensis was studied. For maximum recovery of ACO activity in vitro, the presence of 10% (w/v) insoluble polyvinylpolypyrrolidone (PVPP) and 30% of glycerol in the extraction medium was necessary. The optimum pH for this activity was 7.0. Ethylene production by whole achenes or enzymatic extract increased due to increasing 1-aminocyclopropane-1-carboxylic acid (ACC) concentrations. Saturation level of ACC for in vivo ACO activity was 10-1 M and Vmax was 10.89 nL C2H4·mg protein-1·h-1. For in vitro ACO activity, the saturation level of ACC was 10-3 M and Vmax was 2.299 nL C2H4·mg protein-1·h-1. Both, in vivo and in vitro ACO activities did not follow Michaelis-Menten kinetics. The Hill coefficients (h) were estimated on the basis of non-linear estimation. Their values were 0.63 for in vivo ACO activity and 1.73 for in vitro ACO activity. The experimental data show that ACO from C. chinensis seeds is an oligomeric enzyme with at least two active sites. During seed germination, in vitro ACO activity was detectable after 12 hours of imbibition, while in vivo ACC conversion to ethylene was observed after 24 h, i.e. – after radicle protrusion. The activity of ACO in C. chinensis seeds is associated with germination sensu stricto, and might be a good marker of this process.
Źródło:
Journal of Horticultural Research; 2020, 28, 2; 11-20
2300-5009
Pojawia się w:
Journal of Horticultural Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Antioxidant Enzyme Mechanism of Cluster Bean (Cyamopsis tetragonaloba (L.) Taub). Under Cobalt Stress
Autorzy:
Jayakumar, Kaliyamoorthy
Powiązania:
https://bibliotekanauki.pl/articles/1076708.pdf
Data publikacji:
2019
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Catalase
Cobalt
Cyamopsis tetragonaloba
Peroxidasa
Polyphenol oxidase
Opis:
The research work has been carried out to estimate the low level cobalt application enhance antioxidant enzyme activities of cluster bean plants. The experiments were conducted in earthen pots containing 3 kg of air dried soil. The inner surface of pots was lined with polythene sheet. Cluster bean plants were raised in soil amended with different concentration of cobalt (0, 50, 100, 150, 200 and 250 mg/kg). The antioxidant enzyme activities were analysed at 30, 60, and 90 days after sowing (DAS). There found a significant enhance antioxidant enzyme activities at 50 mg/kg cobalt application in the soil in all the sampling days when compared to control. Further increase in the cobalt level (100-250 mg/kg) in the soil decreased antioxidant enzyme activities of cluster bean plants in all the sampling days.
Źródło:
World News of Natural Sciences; 2019, 24; 64-70
2543-5426
Pojawia się w:
World News of Natural Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Uncoupling proteins in mitochondria of plants and some microorganisms.
Autorzy:
Jarmuszkiewicz, Wiesława
Powiązania:
https://bibliotekanauki.pl/articles/1044176.pdf
Data publikacji:
2001
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
uncoupling protein
alternative oxidase
mitochondria
fatty acid
Opis:
Uncoupling proteins, members of the mitochondrial carrier family, are present in mitochondrial inner membrane and mediate free fatty acid-activated, purine-nucleotide-inhibited H+ re-uptake. Since 1995, it has been shown that the uncoupling protein is present in many higher plants and some microorganisms like non-photosynthetic amoeboid protozoon, Acanthamoeba castellanii and non-fermentative yeast Candida parapsilosis. In mitochondria of these organisms, uncoupling protein activity is revealed not only by stimulation of state 4 respiration by free fatty acids accompanied by decrease in membrane potential (these effects being partially released by ATP and GTP) but mainly by lowering ADP/O ratio during state 3 respiration. Plant and microorganism uncoupling proteins are able to divert very efficiently energy from oxidative phosphorylation, competing for ΔμH+ with ATP synthase. Functional connection and physiological role of uncoupling protein and alternative oxidase, two main energy-dissipating systems in plant-type mitochondria, are discussed.
Źródło:
Acta Biochimica Polonica; 2001, 48, 1; 145-155
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Changes in chemical composition of stored honeydew honeys
Zmiany składu chemicznego przechowywanych miodów spadziowych
Autorzy:
Krauze, A.
Krauze, J.
Powiązania:
https://bibliotekanauki.pl/articles/1402028.pdf
Data publikacji:
1991
Wydawca:
Instytut Rozrodu Zwierząt i Badań Żywności Polskiej Akademii Nauk w Olsztynie
Tematy:
honey
sugars
acidity
invertase
glucose oxidase
catalase
Opis:
Changes in sugars, acidity and activity of enzymes and other components were studies in honeydew honeys stored at room temperature for over two years. The glucose, fructose and saccharose contents decreased, while the content of disaccharides ot her than saccharose increased. Accumulation of lactone of gluconic acid was higher than of free acids. Glucose oxidase and catalase activities and the inhibin value as well as invertase activity decreased to a greater extent than diastase activity.
Miody spadziowe przechowywano ponad 2 lata w temperaturze pokojowej, w ciemności. Po tym okresie następowały znaczne zmiany składu cukrów, który badano stosując rozdział na Bio-Gel P2 i metody enzymatyczne. Zawartość glukozy obniżyła się średnio o 6.33%, fruktozy o 3,49%, a sacharozy oznaczonej eznymatycznie w rozdzielonej frakcji disacharydów o ok. 40%. Ten ubytek sacharozy był zbliżony do zmian sacharozy łącznie z melezytozą oznaczonych na podstawie zawartości cukrów redukujących przed i po hydrolizie kwasowej. Podwyższyła się natomiast zawartość disacharydów innych niż sacharoza (średnio o 45, 17%) i praktycznie nic zmieniła ilość tri i wyższych oligosacharydów. Po przechowywaniu wzrosła kwasowość miodów, a średni wzrost zawartości laktonu był większy niż wolnych kwasów. 5-hydroksymetylofurfural nagromadzał się w różnych ilościach, a przewodność elektryczna i pH utrzymywały się na poziomic zbliżonym do wartości wyjściowych. Długookresowe przechowywanie miodów spadziowych nie spowodowało całkowitej utraty aktywności enzymów. Spadek aktywności inwertazy, który był większy niż diastazy, wynosił średnio ok. 30%. Aktywność oksydazy glukozowej i katalazy, jak również działanie bakteriostatyczne świeżych miodów wahały się w szerokich granicach. Po przechowywaniu obniżenie aktywności oksydazy glukozowej nie było dużo większe niż inwertazy, przy czym aktywności obu enzymów były znacznie skorelowane. Wydaje się, że aktywność inwertazy może w przybliżeniu wskazywać, czy w przechowywanym miodzie spadziowym zachowała się aktywność oksydazy glukozowej i zdolność wytwarzania nadtlenku wodoru, z którą jest związane działanie bakteriostatyczne.
Źródło:
Acta Alimentaria Polonica; 1991, 17(41), 2; 119-126
0137-1495
Pojawia się w:
Acta Alimentaria Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Enzymatic oxidation of substituted tryptamines catalysed by monoamine oxidase
Autorzy:
Dragulska, S.
Kańska, M.
Powiązania:
https://bibliotekanauki.pl/articles/146939.pdf
Data publikacji:
2014
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
monoamine oxidase (MAO)
tryptamine
serotonin
isotope effects
Opis:
The enzymatic deamination of 5-fl uorotryptamine and 5-hydroxytryptamine, 5-HT, catalysed by enzyme monoamine oxidase A (MAO-A, EC 1.4.3.4) was investigated using the kinetic (KIE) and solvent (SIE) isotope effects methods. The numerical values of deuterium isotope effects in the (1R) positions of 5-F-tryptamine were determined using non-competitive spectrophotomeric method. Isotopologue 5-F-[(1R)- -2H]-tryptamine, needed for kinetic studies was obtained by enzymatic decarboxylation of 5'-fl uoro-L-tryptophan, 5'-F-L-Trp, in fully deuteriated medium.
Źródło:
Nukleonika; 2014, 59, 3; 91-95
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Novel laccase-like multicopper oxidases from the Myrothecium roridum fungus - production enhancement, identification and application in the dye removal process
Autorzy:
Jasińska, Anna
Góralczyk, Aleksandra
Soboń, Adrian
Długoński, Jerzy
Powiązania:
https://bibliotekanauki.pl/articles/1038404.pdf
Data publikacji:
2018
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
multicopper oxidases
laccase
bilirubin oxidase
Myrothecium roridum
decolorization
Opis:
The aim of this study was to overproduce, identify and apply novel laccase-like multicopper oxidases (LMCOs) from Myrothecium roridum in a dye removal process. LMCOs' production was enhanced by modifying the medium and adding copper ions. After purification, two proteins, LMCO1 and LMCO2, with molecular masses of 46.7 and 66.3 kDa were discovered. Peptide analysis by mass spectrometry revealed that they belong to the cupredoxin superfamily. Characteristic peptide sequences were obtained for MCOs and bilirubin oxidases. Crude enzymes were applied in a dye decolorization process. Supplementation with 1 mM of vanillin allowed an almost complete elimination of the Indigo carmine within 3 hours. The dye was removed from a solution containing metals, surfactants and organic solvents. The in-gel assessment of the activity and decolorization ability of MCOs, followed by protein extraction and SDS-PAGE, confirmed that only LMCO2 was responsible for the dye removal. MCOs produced by Myrothecium sp. have been poorly studied before. The obtained results broaden knowledge on this subject and may contribute to the development of an eco-friendly method of dye elimination.
Źródło:
Acta Biochimica Polonica; 2018, 65, 2; 287-295
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effects of pH on the activity and structure of choline oxidase from Alcaligenes species
Autorzy:
Hekmat, Azadeh
Saboury, Ali
Moosavi-Movahedi, Ali
Ghourchian, Hedayatollah
Ahmad, Faizan
Powiązania:
https://bibliotekanauki.pl/articles/1040713.pdf
Data publikacji:
2008
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
optimum pH
choline oxidase
nile red
glycine-betaine
Opis:
A reversible effect of pH on the ionization of amino-acid residues at the active center of choline oxidase was observed near the optimum pH (8). Inactivation of choline oxidase took place in the pH ranges 3-6 and 9-11, in which irreversible changes in the structure occur leading to the enzyme inactivation. The first order rate constants of the enzyme's inactivation at various pH values were estimated for the irreversible changes. The Arrhenius analysis revealed no significant changes in the activation enthalpy, while an increase in the activation entropy reflected an increase in the conformational freedom.
Źródło:
Acta Biochimica Polonica; 2008, 55, 3; 549-557
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of growth at low temperature on the alternative pathway respiration in Acanthamoeba castellanii mitochondria.
Autorzy:
Jarmuszkiewicz, Wiesława
Frączyk, Olaf
Hryniewiecka, Lilla
Powiązania:
https://bibliotekanauki.pl/articles/1044102.pdf
Data publikacji:
2001
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
Acanthamoeba castellanii
low temperature adaptation
alternative oxidase
mitochondria
Opis:
Mitochondria of amoeba Acanthamoeba castellanii in addition to the conventional cytochrome pathway possess, like plant mitochondria, a cyanide-resistant alternative quinol oxidase. In mitochondria isolated from amoeba batch culture grown temporarily at low temperature (6°C), higher respiration was accompanied by lower coupling parameters as compared to control culture (grown at 28°C). In the presence of benzohydroxamate, respiratory rates and coupling parameters were similar in both types of mitochondria indicating that growth in cold conditions did not disturb the cytochrome pathway. Increased contribution of alternative oxidase in total mitochondrial respiration in low-temperature-grown amoeba cells was confirmed by calculation of its contribution using ADP/O measurements. Furthermore, in mitochondria from low-temperature- grown cells the content of the alternative oxidase was increased and correlated with the increase in the unstimulated and GMP-stimulated cyanide-resistant respiratory activity. A possible physiological role of higher activity of alternative oxidase as response to growth at a low temperature in unicellular organisms, such as amoeba, is discussed.
Źródło:
Acta Biochimica Polonica; 2001, 48, 3; 729-737
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Molecular cloning and characterization of pearl millet polyphenol oxidase and its role in defense against downy mildew
Autorzy:
Niranjan-Raj, S.
Lavanya, S.N.
Nayaka, S.C.
Powiązania:
https://bibliotekanauki.pl/articles/2084674.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
downy mildew
plant defense
Pennisetum glaucum
polyphenol oxidase
Opis:
Polyphenol oxidase partial gene PG-PPO was cloned and characterized from Pennisetum glaucum (pearl millet) which showed 42% identity to a PPO sequence isolated from wheat at the region of Copper B with a score of 40 and e-value of 2.8. Multiple sequence alignment results revealed similarity to polyphenol oxidase (PPO) sequences from wheat, trifolium, lettuce, apricot, tobacco, tomato, pokeweed, apple, grape and poplar especially at the Copper B region of PPO. The 395 bp pearl millet PPO sequence was AT rich (53.3%) and contained the highly conserved amino acids of histidine-rich copper binding sites similar to PPO sequences from other crops. Results also indicated that PPO in pearl millet exists in multi copy. The role of the isolated PPO gene during pearl millet-downy mildew interaction was analyzed and the results showed significantly higher and rapid accumulation of PPO mRNAs in resistant pearl millet seedlings inoculated with Sclerospora graminicola in comparison to the susceptible control, demonstrating that the PPO plays a prominent role in pearl millet defense against pathogens, particularly downy mildew pathogen.
Źródło:
Journal of Plant Protection Research; 2019, 59, 3; 423-427
1427-4345
Pojawia się w:
Journal of Plant Protection Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Cloning, expression and characterization of thermostable YdaP from Bacillus licheniformis 9A
Autorzy:
Wani Lako, Joseph
Yengkopiong, Jada
Stafford, William
Tuffin, Marla
Cowan, Don
Powiązania:
https://bibliotekanauki.pl/articles/1038524.pdf
Data publikacji:
2018
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
Bacillus licheniformis
pyruvate oxidase
YdaP
thiamine diphosphate enzyme
Opis:
The Bacillus licheniformis ydaP gene encodes for a pyruvate oxidase that catalyses the oxidative decarboxylation of pyruvate to acetate and CO2. The YdaP form of this enzyme was purified about 48.6-folds to homogeneity in three steps. The enzyme was recovered in a soluble form and demonstrated significant activity on pyruvate using 2, 6-dichlorophenolindophenol (DCPIP) as an artificial electron acceptor. HPLC analysis of the YdaP-enzyme catalysed conversion of pyruvate showed acetate as the sole product, confirming the putative identity of pyruvate oxidase. Analysis of the substrate specificity showed that the YdaP enzyme demonstrated preference for short chain oxo acids; however, it was activated by 1% Triton X-100. The YdaP substrate-binding pocket from the YdaP protein differed substantially from the equivalent site in all of the so far characterized pyruvate oxidases, suggesting that the B. licheniformis YdaP might accept different substrates. This could allow more accessibility of large substrates into the active site of this enzyme. The thermostability and pH activity of the YdaP enzyme were determined, with optimums at 50ºC and pH 5.8, respectively. The amino acid residues forming the catalytic cavity were identified as Gln460 to Ala480.
Źródło:
Acta Biochimica Polonica; 2018, 65, 1; 59-66
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Deuterium isotope effects in oxidation of dopamine by tyramine oxidase
Autorzy:
Pająk, M.
Byszewska, W.
Kańska, M.
Powiązania:
https://bibliotekanauki.pl/articles/147724.pdf
Data publikacji:
2013
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
deuterium
dopamine (DA)
isotope effects
oxidation
tyramine oxidase
Opis:
We report the studies on the mechanism of oxidation of dopamine (DA) to 3’,4’-dihydroxyphenylacetaldehyde (DOPAL) by enzyme tyramine oxidase (EC 1.4.3.6) using kinetic isotope effects (KIE) and solvent isotope effects (SIE) methods. For kinetic studies, the selectively deuterium labelled isotopologues of dopamine, i.e., [(1R)-2H]-, and [(1S)- -2H]-DA were used. The numerical values of KIE’s for the (1R)- and (1S)-isotopologues of dopamine in the enzymatic oxidation of DA to DOPAL were determined using the non competitive spectrophotometric method. Also, the SIE’s for this reaction carried out in heavy water were obtained spectrophotometrically. Some mechanistic details of enzymatic oxidation of DA to DOPAL were discussed.
Źródło:
Nukleonika; 2013, 58, 2; 255-259
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Molecular genetics of exfoliation syndrome
Genetyka molekularna zespołu pseudoeksfoliacji
Autorzy:
Kasım, Burcu
Mocan, Mehmet Cem
İrkeç, Murat
Powiązania:
https://bibliotekanauki.pl/articles/1929154.pdf
Data publikacji:
2015
Wydawca:
Medical Education
Tematy:
exfoliation glaucoma
exfoliation syndrome
genetics
lysyl oxidase-like 1
Opis:
Exfoliation syndrome is an age-related disorder of the extracellular matrix, characterized by progressive accumulation of abnormal fibrillar material in several ocular and extraocular tissues. Although the exact etiopathogenesis is still unknown, several genetic and environmental factors appear to be involved in disease pathogenesis. Recently, single nucleotide polymorphisms in lysyl oxidase-like 1 have been found to be strongly associated with exfoliation syndrome. Dysregulation of lysyl oxidase-like 1 specifity and activity, an enzyme with a role in tropoelastin cross-linking and elastin homeostasis is thought to be involved in the development of exfoliation syndrome. This review aims to examine the recent genetic findings in the disease process.
Zespół pseudoeksfoliacji to związane z wiekiem zaburzenie macierzy zewnątrzkomórkowej, charakteryzujące się postępującym odkładaniem się nieprawidłowego materiału fibrylarnego w różnych tkankach oka i poza nimi. Dokładna etiopatogeneza choroby pozostaje nieznana, jednak wydaje się, że istnieje kilka czynników genetycznych i środowiskowych w nią zaangażowanych. Niedawno wykazano, że polimorfizmy pojedynczego nukleotydu w obrębie oksydazy lizynowej 1 są silnie powiązane z zespołem pseudoeksfoliacji. Dysregulacja swoistości i aktywności oksydazy lizynowej 1, czyli enzymu odgrywającego rolę w sieciowaniu tropoelastyny i homeostazie elastyny, jest uważana za jeden z czynników rozwoju zespołu pseudoeksfoliacji. Celem niniejszej pracy jest przeanalizowanie najnowszych doniesień dotyczących genetyki wspomnianego procesu chorobowego.
Źródło:
OphthaTherapy; 2015, 2, 1; 13-20
2353-7175
2543-9987
Pojawia się w:
OphthaTherapy
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Properties, various functions and application of bacterial melanins – some properties and possible application of melanin produced by Azotobacter chroococcum
Autorzy:
Kozieł, Monika
Powiązania:
https://bibliotekanauki.pl/articles/2163439.pdf
Data publikacji:
2023-01-31
Wydawca:
Instytut Uprawy Nawożenia i Gleboznawstwa – Państwowy Instytut Badawczy
Tematy:
bacterial melanin
polyphenol oxidase
stress protection
biosynthesis
Azotobacter chroococcum
Opis:
Melanins are a group of macromolecular pigments formed as a result of oxidative polymerization of phenolic and indole compounds. They are considered the most common, heterogeneous, resistant and evolutionarily oldest pigments found in nature. Melanins occurrred very early in the evolution of various groups of organisms. They have already been found in dinosaur, bird and primitive cephalopod fossils. Today, melanins are found in every kingdom of living organisms and play an important role in the processes of reproduction, thermoregulation, chemoprotection and camouflage. In addition to the important functions they perform in organisms, they exhibit a different chemical structure and are characterized by a wide range of colors, from black-brown to yellow-red. Differences in chemical structure have become the criterion for dividing melanins into four groups, i.e. eumelanin, allomelanin, pheomelanin and neuromelanin. Production of melanins is characteristic for many microorganisms, including free-living Azotobacter bacteria. The genus Azotobacter comprises eight species and only Azotobacter bryophylli does not produce pigments. Azotobacter chroococcum, the most abundant in soils all over the world, produces a dark brown melanin pigment non-diffusible into the substrate. Melanins synthesized by this species of bacteria increased the growth of some plants and detoxification of soils and waters polluted with heavy metals. In addition, the method of obtaining melanin produced by A. chroococcum is simple and relatively cheap compared to the cost of obtaining synthetic melanins, which gives the opportunity to conduct further research on the use of this pigment in biotechnology and molecular biology. In work it was describe the physicochemical properties, various functions and possible applications of bacterial melanins in various industries. The publication also summarizes the current knowledge on some properties and the possibility of use in bioremediation of soils and waters contaminated with heavy metals melanins synthesized by Azotobacter chroococcum.
Źródło:
Polish Journal of Agronomy; 2022, 51; 46-54
2081-2787
Pojawia się w:
Polish Journal of Agronomy
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Calcium dependent regulation of the Arabidopsis NADPH oxidase RbohF by CBL-CIPK complexes
Autorzy:
Drerup, M.
Hashimoto, K.
Schlucking, K.
Steinhorst, L.
Manishankar, P.
Kuchitsu, K.
Kudla, J.
Powiązania:
https://bibliotekanauki.pl/articles/80351.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
conference
reactive oxygen species
calcium accumulation
plant
NADPH oxidase
Arabidopsis
Źródło:
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology; 2013, 94, 2
0860-7796
Pojawia się w:
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Enancjoselektywna enzymatyczna desymetryzacja katalizowana oksydoreduktazami. Reakcje utleniania. Część 2
Enantioselective enzymatic desymmetrization catalyzed by oxidoreductases. Oxidation reactions. Part 2
Autorzy:
Karczmarska-Wódzka, A.
Kołodziejska, R.
Tafelska-Kaczmarek, A.
Studzińska, R.
Wróblewski, M.
Augustyńska, B.
Powiązania:
https://bibliotekanauki.pl/articles/172457.pdf
Data publikacji:
2015
Wydawca:
Polskie Towarzystwo Chemiczne
Tematy:
dioksygenaza
oksydaza
peroksydaza
reakcja utleniania
dioxygenase
oxidase
peroxidase
oxidation reaction
Opis:
In continuation of our work, we herein describe next enzyme classes applied for oxidation reaction. Dioxygenases, oxidases, and peroxidases are successfully used in the synthesis of desymmetrization products with high yields and enantiomeric excesses. Aromatic dioxygenases, such as toluene dioxygenase (TDO), naphthalene dioxygenase (NDO), and biphenyl dioxygenase (BPDO) found in the prokaryotic microorganisms are enzymes belonging to the dioxygenase class and are the most commonly used in organic synthesis. The α-oxidation of various fatty acids in the presence of an α-oxidase from germinating peas is one of the few examples of oxidases application in asymmetric organic synthesis. The intermediary α-hydroxyperoxyacids can undergo two competing reactions: decarboxylation of the corresponding aldehydes or reduction to the (R)-2-hydroxy acids. In order to eliminate the competitive decarboxylation reaction tin(II) chloride is used as an in situ reducing agent. Peroxidases are the redox enzymes found in various sources such as animals, plants, and microorganisms. Due to the fact that, in contrast to monooxygenases, no additional cofactors are required, peroxidases are highly attractive for the preparative biotransformation. Oxidation reactions catalyzed by (halo)peroxydases are also often used in organic synthesis. N-Oxidation of amines, for instance, leads to the formation of the corresponding aliphatic N-oxides, aromatic nitro-, or nitrosocompounds. From a preparative synthesis standpoint, however, sulfoxidation of thioether is important since it was proven to proceed in a highly stereo- and enantioselective manner. Furthermore, depending on the source of haloperoxidase, chiral sulfoxides of opposite configurations can be obtained.
Źródło:
Wiadomości Chemiczne; 2015, 69, 1-2; 53-64
0043-5104
2300-0295
Pojawia się w:
Wiadomości Chemiczne
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Kinetics properties of polyphenol oxidase in hawthorn (Crataegus spp.)
Autorzy:
Saeidian, S.
Powiązania:
https://bibliotekanauki.pl/articles/10795.pdf
Data publikacji:
2014
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
kinetic property
polyphenol oxidase
hawthorn
Crataegus
purification
inhibition
thermal inactivation
Opis:
Polyphenol oxidase (PPO) from hawthorn was extracted and partially purified through (NH4)2SO4 precipitation, dialysis and ion exchange chromatography. The activity of polyphenol oxidase was investigated in Crataegus spp. Spectrophotometric method was used to assay the enzyme activity and the kinetic constants - maximum enzyme velocity (Vmax) and Michealis - Menten constant (Km). Of the substrates tested, catechol was the best substrate for PPO with a Km value of 2.2 mM. The optimum pH for PPO activity was found to be 7. The enzyme showed high activity over a broad pH range of 4 - 8. The optimal pH and temperature for enzyme activity were found to be 7 and 40-45 °C, respectively. km value for hawthorn PPO is calculated 22 mM for catechol and 6.7 mM for pyrogallol and 9.7 mM for L-dopa. As can be seen, affinity of PPOs for various substrates varies widely. The enzyme showed a broad activity over a broad pH and temperature range. The thermal inactivation studies showed that the enzyme is heat resistant. The enzyme showed the highest activity toward pyrogallol and no activity toward tyrosine. Of the inhibitors tested, the most potent inhibitors were kojic acid, cysteine and glycine , respectively.
Źródło:
International Letters of Natural Sciences; 2014, 20
2300-9675
Pojawia się w:
International Letters of Natural Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Endothelial NADH/NADPH-dependent enzymatic sources of superoxide production: relationship to endothelial dysfunction.
Autorzy:
Kalinowski, Leszek
Malinski, Tadeusz
Powiązania:
https://bibliotekanauki.pl/articles/1043282.pdf
Data publikacji:
2004
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
peroxynitrite
endothelial dysfunction
NAD(P)H oxidase
nitric oxide
superoxide
eNOS
Opis:
There is growing evidence that endothelial dysfunction, which is often defined as the decreased endothelial-derived nitric oxide (NO) bioavailability, is a crucial factor leading to vascular disease states such as hypertension, diabetes, atherosclerosis, heart failure and cigarette smoking. This is due to the fact that the lack of NO in endothelium-dependent vascular disorders contributes to impaired vascular relaxation, platelet aggregation, increased vascular smooth muscle proliferation, and enhanced leukocyte adhesion to the endothelium. During the last several years, it has become clear that reduction of NO bioavailability in the endothelium-impaired function disorders is associated with an increase in endothelial production of superoxide (O2̇̄). Because O2̇̄ rapidly scavenges NO within the endothelium, a reduction of bioactive NO might occur despite an increased NO generation. Among many enzymatic systems that are capable of producing O2̇̄, NAD(P)H oxidase and uncoupled endothelial NO synthase (eNOS) apparently are the main sources of O2̇̄ in the endothelial cells. It seems that O2̇̄ generated by NAD(P)H oxidase may trigger eNOS uncoupling and contribute to the endothelial balance between NO and O2̇̄. That is maintained at diverse levels.
Źródło:
Acta Biochimica Polonica; 2004, 51, 2; 459-469
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-25 z 79

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