Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

Wyszukujesz frazę "Mariusz" wg kryterium: Autor


Tytuł:
Personal remarks on the future of protein crystallography and structural biology
Autorzy:
Jaskolski, Mariusz
Powiązania:
https://bibliotekanauki.pl/articles/1040362.pdf
Data publikacji:
2010
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
high-throughput crystallography
single-particle imaging
synchrotron radiation
X-ray free-electron laser
structural genomics
Opis:
Protein crystallography, the main experimental method of structural biology, has undergone in the recent past three revolutionary changes leading to its unexpected renaissance. They were connected with (i) the introduction of synchrotron radiation sources for X-ray diffraction experiments, (ii) implementation of Se-Met multiwavelength anomalous diffraction (MAD) for phasing, and (iii) initiation of structural genomics (SG) programs. It can be foreseen that in the next 10-15 years protein crystallography will continue to be in this revolutionary phase. We can expect not only an avalanche of protein crystal structures from SG centers, but also attacking of more demanding projects, such as the structure of membrane proteins and of very large macromolecular complexes. On the technological front, the introduction of X-ray radiation from free-electron lasers will revolutionize the experimental possibilities, making feasible even the imaging of single molecules and of intact biological cells.
Źródło:
Acta Biochimica Polonica; 2010, 57, 3; 261-264
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
3D Domain swapping, protein oligomerization, and amyloid formation.
Autorzy:
Jaskólski, Mariusz
Powiązania:
https://bibliotekanauki.pl/articles/1043850.pdf
Data publikacji:
2001
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
protein aggregation
amyloid
amyloid fibrils
3D domain swapping
conformational diseases
amyloidosis
Opis:
In 3D domain swapping, first described by Eisenberg, a structural element of a monomeric protein is replaced by the same element from another subunit. This process requires partial unfolding of the closed monomers that is then followed by adhesion and reconstruction of the original fold but from elements contributed by different subunits. If the interactions are reciprocal, a closed-ended dimer will be formed, but the same phenomenon has been suggested as a mechanism for the formation of open-ended polymers as well, such as those believed to exist in amyloid fibrils. There has been a rapid progress in the study of 3D domain swapping. Oligomers higher than dimers have been found, the monomer-dimer equilibrium could be controlled by mutations in the hinge element of the chain, a single protein has been shown to form more than one domain-swapped structure, and recently, the possibility of simultaneous exchange of two structural domains by a single molecule has been demonstrated. This last discovery has an important bearing on the possibility that 3D domain swapping might be indeed an amyloidogenic mechanism. Along the same lines is the discovery that a protein of proven amyloidogenic properties, human cystatin C, is capable of 3D domain swapping that leads to oligomerization. The structure of do-main-swapped human cystatin C dimers explains why a naturally occurring mutant of this protein has a much higher propensity for aggregation, and also suggests how this same mechanism of 3D domain swapping could lead to an open-ended polymer that would be consistent with the cross-β structure, which is believed to be at the heart of the molecular architecture of amyloid fibrils.
Źródło:
Acta Biochimica Polonica; 2001, 48, 4; 807-827
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A study of free radical chemistry: their role and pathophysiological significance
Autorzy:
Gutowski, Mariusz
Kowalczyk, Sławomir
Powiązania:
https://bibliotekanauki.pl/articles/1039594.pdf
Data publikacji:
2013
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
ascorbic acid
reactive nitrogen species
catalytic ions
reactive oxygen species
lipid peroxidation
Opis:
Oxygen is one of the most important molecules on Earth mainly because of the biochemical symmetry of oxygenic photosynthesis and aerobic respiration that can maintain homeostasis within our planet's biosphere. Oxygen can also produce toxic molecules, reactive oxygen species (ROS). ROS play a dual role in biological systems, since they can be either harmful or beneficial to living systems. They can be considered a double-edged sword because at moderate concentrations, nitric oxide (NO•), superoxide anion, and related reactive oxygen species play an important role as regulatory mediators in signalling processes. Many of the ROS-mediated responses actually protect the cells against oxidative stress and re-establish "redox homeostasis". On the other hand, overproduction of ROS has the potential to cause damage. In the recent decades, ROS has become a focus of interest in most biomedical disciplines and many types of clinical research. Increasing evidence from research on several diseases shows that oxidative stress is associated with the pathogenesis of diabetes mellitus, obesity, cancer, cardiovascular diseases, inflammation, ischaemia/reperfusion injury, obstructive sleep apnea, neurodegenerative disorders, hypertension and ageing.
Źródło:
Acta Biochimica Polonica; 2013, 60, 1; 1-16
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Structural aspects of l-asparaginases, their friends and relations
Autorzy:
Michalska, Karolina
Jaskolski, Mariusz
Powiązania:
https://bibliotekanauki.pl/articles/1041150.pdf
Data publikacji:
2006
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
Ntn-hydrolase
l-asparaginase
isoaspartyl peptidase
Opis:
Enzymes capable of converting l-asparagine to l-aspartate can be classified as bacterial-type or plant-type l-asparaginases. Bacterial-type l-asparaginases are further divided into subtypes I and II, defined by their intra-/extra-cellular localization, substrate affinity, and oligomeric form. Plant-type l-asparaginases are evolutionarily and structurally distinct from the bacterial-type enzymes. They function as potassium-dependent or -independent Ntn-hydrolases, similar to the well characterized aspartylglucosaminidases with (αβ)2 oligomeric structure. The review discusses the structural aspects of both types of l-asparaginases and highlights some peculiarities of their catalytic mechanisms. The bacterial-type enzymes are believed to have a disordered active site which gets properly organized on substrate binding. The plant-type enzymes, which are more active as isoaspartyl aminopeptidases, pose a chemical challenge common to other Ntn-hydrolases, which is how an N-terminal nucleophile can activate itself or cleave its own α-amide bond before the activation is even possible. The K+-independent plant-type l-asparaginases show an unusual sodium coordination by main-chain carbonyl groups and have a key arginine residue which by sensing the arrangement at the oligomeric (αβ)-(αβ) interface is able to discriminate among substrates presented for hydrolysis.
Źródło:
Acta Biochimica Polonica; 2006, 53, 4; 627-640
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Alternative therapies in Staphylococcus aureus diseases
Autorzy:
Kurlenda, Julianna
Grinholc, Mariusz
Powiązania:
https://bibliotekanauki.pl/articles/1039729.pdf
Data publikacji:
2012
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
Staphylococcus aureus diseases
alternative therapies
Opis:
Staphylococcus aureus is a common pathogen responsible for health-care-associated infections as well as community acquired ones. It is the etiological factor of a wide spectrum of infections. Therapeutic problems are caused by resistance of S. aureus to many antibiotics, specifically to methicillin (methicillin-resistant S. aureus, MRSA). In such cases a limited spectrum of antibiotics may be used and prolonged hospitalization is costly. Hence, there is an urgent need for the development of alternative antibiotic therapeutics. This work reviews the current knowledge concerning prospective treatment of staphylococcal diseases.
Źródło:
Acta Biochimica Polonica; 2012, 59, 2; 171-184
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Generation of reactive oxygen species by a sufficient, insufficient and varicose vein wall
Autorzy:
Krzyściak, Wirginia
Kózka, Mariusz
Powiązania:
https://bibliotekanauki.pl/articles/1039956.pdf
Data publikacji:
2011
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
varicose vein
superoxide dismutase
oxidative stress
Opis:
Despite numerous theories, the etiology and pathogenesis of primary varicose veins remain unclear. The etiology of chronic venous diseases (CVDs) known as chronic venous insufficiency (CVI) is related to leukocyte trapping. Leukocyte trapping involves trapping of white cells in vessel walls followed by their activation and translocation outside the vessel. Release of reactive oxygen species (ROS) from trapped white cells has been documented. Superoxide dismutase (SOD) directly inhibits the generation of free radicals and compounds that are produced during oxidation by ROS, such as malonyldialdehyde (MDA). The aim of this study was to determine the involvement of free radicals in the etiology of venous changes. The following material was used for the study: fragments of sufficient or insufficient venous system and varices from 31 patients diagnosed with chronic venous disease in the 2nd or 3rd degree, according to clinical state, etiology, anatomy and pathophysiology (CEAP), which were qualified for surgical procedure. The levels of oxidative stress markers strongly correlated with lesions observed by USG in insufficient and varicose veins. In both a higher concentration of MDA was observed, which is a sign of lipid peroxidation. Antioxidative mechanisms, SOD activity and total antioxidative power expressed as FRAP were inversely proportional to MDA concentration. In insufficient and varicose veins both FRAP and SOD activities were significantly lower than in normal veins. The severity of clinical changes was inversely dependent on the efficiency of scavenging of ROS, which additionally proves the participation of free radicals in pathogenesis of CVDs.
Źródło:
Acta Biochimica Polonica; 2011, 58, 1; 89-94
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Sequence analysis of enzymes with asparaginase activity.
Autorzy:
Borek, Dominika
Jaskólski, Mariusz
Powiązania:
https://bibliotekanauki.pl/articles/1044033.pdf
Data publikacji:
2001
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
N-terminal nucleophile hydrolase
lysophospholipase
tRNA amidotransferase
aspartylglucosaminidase
asparaginase
L-asparagine
Opis:
Asparaginases catalyze the hydrolysis of asparagine to aspartic acid and ammonia. Enzymes with asparaginase activity play an important role both in the metabolism of all living organisms as well as in pharmacology. The main goal of this paper is to attempt a classification of all known enzymes with asparaginase activity, based on their amino acid sequences. Some possible phylogenetic consequences are also discussed using dendrograms and structural information derived from crystallographic studies.
Źródło:
Acta Biochimica Polonica; 2001, 48, 4; 893-902
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Why a "benign" mutation kills enzyme activity. Structure-based analysis of the A176V mutant of Saccharomyces cerevisiae L-asparaginase I
Autorzy:
Bonthron, David
Jaskólski, Mariusz
Powiązania:
https://bibliotekanauki.pl/articles/1044922.pdf
Data publikacji:
1997
Wydawca:
Polskie Towarzystwo Biochemiczne
Źródło:
Acta Biochimica Polonica; 1997, 44, 3; 491-504
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Isolation and characterisation of crocodile and python ovotransferrins
Autorzy:
Ciuraszkiewicz, Justyna
Olczak, Mariusz
Wątorek, Wiesław
Powiązania:
https://bibliotekanauki.pl/articles/1041133.pdf
Data publikacji:
2007
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
python
Crocodylus rhombifer
crocodile
Crocodylus niloticus
iron release
Python molarus bivittatus
ovotransferrin
N-glycans
Opis:
Transferrins play a major role in iron homeostasis and metabolism. In vertebrates, these proteins are synthesised in the liver and dispersed within the organism by the bloodstream. In oviparous vertebrates additional expression is observed in the oviduct and the synthesised protein is deposited in egg white as ovotransferrin. Most research on ovotransferrin has been performed on the chicken protein. There is a limited amount of information on other bird transferrins, and until our previous paper on red-eared turtle protein there was no data on the isolation, sequencing and biochemical properties of reptilian ovotransferrins. Recently our laboratory deposited ten new sequences of reptilian transferrins in the EMBL database. A comparative analysis of these sequences indicates a possibility of different mechanisms of iron release among crocodile and snake transferrin. In the present paper we follow with the purification and analysis of the basic biochemical properties of two crocodile (Crocodilus niloticus, C. rhombifer) and one snake (Python molurus bivittatus) ovotransferrins. The proteins were purified by anion exchange and hydrophobic chromatography, and their N-terminal amino-acid sequences, molecular mass and isoelectric points were determined. All three proteins are glycosylated and their N-glycan chromatographic profiles show the largest contribution of neutral oligosaccharides in crocodile and disialylated glycans in python ovotransferrin. The absorption spectra of iron-saturated transferrins were analysed. Iron release from these proteins is pH-dependent, showing a biphasic character in crocodile ovotransferrins and a monophasic type in the python protein. The reason for the different types of iron release is discussed.
Źródło:
Acta Biochimica Polonica; 2007, 54, 1; 175-182
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Stem cell biology - a never ending quest for understanding.
Autorzy:
Majka, Marcin
Kucia, Magdalena
Ratajczak, Mariusz
Powiązania:
https://bibliotekanauki.pl/articles/1041413.pdf
Data publikacji:
2005
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
stem cells
TCSC
plasticity
Opis:
Stem cells (SC) research is an important part of biotechnology that could lead to the development of new therapeutic strategies. A lot of effort has been put to understand biology of the stem cells and to find genes and subsequently proteins that are responsible for their proliferation, self-renewal and differentiation. Different cytokines and growth factors has been used to expand stem cells, but no combination of these factors was identified that could effectively expand the most primitive stem cells. Recently, however, genes and receptors responsible for SC proliferation and differentiation have been described. Ligands for these receptors or these genes themselves are being already used for ex vivo expansion of stem cells and the first data are very promising. New markers, such as CXCR4 and CD133, have been discovered and shown to be present on surface of hematopoietic stem cells. The same markers were recently also found to be expressed on neuronal-, hepatic- or skeletal muscle-stem cells. By employing these markers several laboratories are trying to isolate stem cells for potential clinical use. New characteristics of stem cells such as transdifferentiation and cell fusion have been described. Our team has identified a population of tissue committed stem cells (TCSC). These cells are present in a bone marrow and in other tissues and they can differentiate into several cell types including cardiac, neural and liver cells.
Źródło:
Acta Biochimica Polonica; 2005, 52, 2; 353-358
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A comparison of the in vitro genotoxicity of anticancer drugs idarubicin and mitoxantrone.
Autorzy:
Błasiak, Janusz
Gloc, Ewa
Warszawski, Mariusz
Powiązania:
https://bibliotekanauki.pl/articles/1043821.pdf
Data publikacji:
2002
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
mitoxantrone
oxidative DNA damage
DNA damage
idarubicin
comet assay
DNA methylation
DNA repair
Opis:
Idarubicin is an anthracycline antibiotic used in cancer therapy. Mitoxantrone is an anthracycline analog with presumed better antineoplastic activity and lesser toxicity. Using the alkaline comet assay we showed that the drugs at 0.01-10 μM induced DNA damage in normal human lymphocytes. The effect induced by idarubicin was more pronounced than by mitoxantrone (P < 0.001). The cells treated with mitoxantrone at 1 μM were able to repair damage to their DNA within a 30-min incubation, whereas the lymphocytes exposed to idarubicin needed 180 min. Since anthracyclines are known to produce free radicals, we checked whether reactive oxygen species might be involved in the observed DNA damage. Catalase, an enzyme inactivating hydrogen peroxide, decreased the extent of DNA damage induced by idarubicin, but did not affect the extent evoked by mitoxantrone. Lymphocytes exposed to the drugs and treated with endonuclease III or formamidopyrimidine-DNA glycosylase (Fpg), enzymes recognizing and nicking oxidized bases, displayed a higher level of DNA damage than the untreated ones. 3-Methyladenine-DNA glycosylase II (AlkA), an enzyme recognizing and nicking mainly methylated bases in DNA, increased the extent of DNA damage caused by idarubicin, but not that induced by mitoxantrone. Our results indicate that the induction of secondary malignancies should be taken into account as side effects of the two drugs. Direct strand breaks, oxidation and methylation of the DNA bases can underlie the DNA-damaging effect of idarubicin, whereas mitoxantrone can induce strand breaks and modification of the bases, including oxidation. The observed in normal lymphocytes much lesser genotoxicity of mitoxantrone compared to idarubicin should be taken into account in planning chemotherapeutic strategies.
Źródło:
Acta Biochimica Polonica; 2002, 49, 1; 145-155
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł

Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies