Wszystkie pola: Olczak, Wiesław - Katalog OPAC zbiorów

Skocz do pozycji: 1.

Tytuł:: Plant purple acid phosphatases - genes, structures and biological function.
Autorzy:: Olczak, Mariusz
Morawiecka, Bronisława
Wątorek, Wiesław
Powiązania:: https://bibliotekanauki.pl/articles/1043418.pdf
Data publikacji:: 2003
Wydawca:: Polskie Towarzystwo Biochemiczne
Tematy:: metallophosphatases
plant purple acid phosphatases
Opis:: The properties of plant purple acid phosphatases (PAPs), metallophosphoesterases present in some bacteria, plants and animals are reviewed. All members of this group contain a characteristic set of seven amino-acid residues involved in metal ligation. Animal PAPs contain a binuclear metallic center composed of two irons, whereas in plant PAPs one iron ion is joined by zinc or manganese ion. Among plant PAPs two groups can be distinguished: small PAPs, monomeric proteins with molecular mass around 35 kDa, structurally close to mammalian PAPs, and large PAPs, homodimeric proteins with a single polypeptide of about 55 kDa. Large plant PAPs exhibit two types of structural organization. One type comprises enzymes with subunits bound by a disulfide bridge formed by cysteines located in the C-terminal region around position 350. In the second type no cysteines are located in this position and no disulfide bridges are formed between subunits. Differences in structural organisation are reflected in substrate preferences. Recent data reveal in plants the occurrence of metallophosphoesterases structurally different from small or large PAPs but with metal-ligating sequences characteristic for PAPs and expressing pronounced specificity towards phytate or diphosphate nucleosides and inorganic pyrophosphate.
Źródło:: Acta Biochimica Polonica; 2003, 50, 4; 1245-1256
0001-527X
Pojawia się w:: Acta Biochimica Polonica
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 2.

Tytuł:: Analysis of individual azurocidin N-glycosylation sites in regard to its secretion by insect cells, susceptibility to proteolysis and antibacterial activity
Autorzy:: Indyk, Katarzyna
Olczak, Teresa
Ciuraszkiewicz, Justyna
Wątorek, Wiesław
Olczak, Mariusz
Powiązania:: https://bibliotekanauki.pl/articles/1041040.pdf
Data publikacji:: 2007
Wydawca:: Polskie Towarzystwo Biochemiczne
Tematy:: glycosylation
protein secretion
azurocidin
antimicrobial activity
Opis:: Azurocidin is an inactive serine protease homolog with primary sequence similarity to neutrophil elastase, cathepsin G, and proteinase 3. The aim of this study was to investigate possible consequences of differential glycosylation of azurocidin in regard to its secretion, protein stability as measured by susceptibility to proteolysis, and antibacterial activity. Site-directed mutagenesis was employed to generate mutant azurocidin variants lacking individual N-glycosylation sites. Our results show that N-linked glycans may play a role in proper azurocidin folding and subsequent secretion by insect cells. We also demonstrate that N-linked glycosylation contributes to azurocidin stability by protecting it from proteolysis. The lack of N-glycosylation at individual sites does not significantly influence the azurocidin antibacterial activity.
Źródło:: Acta Biochimica Polonica; 2007, 54, 3; 567-573
0001-527X
Pojawia się w:: Acta Biochimica Polonica
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 3.

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