Wyniki wyszukiwania

1

An isotopic assay of dUTPase activity based on coupling with thymidylate synthase

100%

Golos B., Rode W.

Acta Biochimica Polonica

|

1999

|

tom 46

|

nr 3

A new rapid, sensitive and convenient procedure is presented allowing determination of dUTPase activity. With [5-3H]dUTP used as the substrate, dUTPase, converts it to the corresponding monophosphate and is coupled with a thymidylate synthase-catalyzed reaction, resulting in tritium release from [5-3H]dUMP. Following charcoal absorption of the labeled nuleotides, radioactivity of tritiated water is determined. The new assay was tested to show comparable results with a previously described assay, based on measuring dUTPase-catalyzed [5-3H]dUMP production.

2

Diminished expression of adenosine kinase in diabetic rats

63%

Sakowicz M., Pawelczyk T.

Cellular and Molecular Biology Letters

|

1999

|

tom 04

|

nr 3

3

Acyclic analogues of 5-fluoro-dUMP and 5-fluoro-2'-deoxyuridine: Synthesis and inhibition of thymidylate synthase and tumour cell growth

63%

Felczak K., Golos B., Dzik J., Rode W., Bretner M., Shugar D., Kulikowski T.

Acta Biochimica Polonica

|

1998

|

tom 45

|

nr 1

1-[(2-Hydroxyethoxy)methyl]-5-fluorouracil (HEMFU) and 1-[(1,3-dihydroxy-2-propoxy)methyl]-5-fluorouracil (DHPFU) were prepared by alkylation of the di-O-TMS derivative of 5-fluorouracil and phosphorylated with the use of the wheat shoot phosphotransferase system to their monophosphates, HEMFUMP and DHPFUMP. 1-(2-Phosphonylmethoxyethyl)-5-fluorouracil (PMEFU) was obtained by condensation of diethyl-2-chloroethoxymethanephosphonate with 5-fluorouracil and cleavage of the alkylphosphoester with trimethylbromosilane. Inhibition of highly purified thymidylate synthase from mouse tumour Ehrlich carcinoma and leukemia L1210 cells by each of the nucleotide analogues, DHPFUMP, PMEFU and HEMFUMP, and of L5178Y mouse leukemia cell growth by the nucleoside (HEMFU) analogue, were studied. DHPFUMP proved to be the strongest inhibitor, non-competitive vs dUMP, with Kiapp 2.8 μM for time-independent interaction with the enzyme and N5,N10-methylenetetrahydrofolate (CH2H4PteGlu). In the presence of CH2H4PteGlu, DHPFUMP exhibited time-dependent inactivation of the enzyme, the inactivation rate plots being biphasic and pointing to Ki values in the μM range (103-fold higher than for 5-fluoro-dUMP). HEMFUMP and PMEFU were much weaker inhibitors of the enzyme, with Kiapp values of 0.26 μM (non-competitive vs dUMP) and 30 mM (non-competitive vs dUMP), respectively. HEMFU, despite the weak interaction of its nucleotide analogue with the enzyme, proved to be a strong cell (L5178Y) growth inhibitor, with IC50 in the range 10-5 M.

4

Stucture-activity relationships for phosphorylation of nucleoside analogs to monophosphates by nucleoside kinases

63%

Johansson N. G., Eriksson S.

Acta Biochimica Polonica

|

1996

|

tom 43

|

nr 1

The mammalian deoxyribonucleoside kinases thymidine kinase 1 and 2, deoxy- cytidine kinase and deoxyguanosine kinase phosphorylate deoxyribonucleosides and provide an alternative to de novo synthesis of DNA precursors. Their activities are essential for activation of several chemotherapeutically important nucleoside analogs. These four salvage kinase enzymes exhibit distinct substrate specificities for nucleoside analogs modified in the base and glycon moieties. In this review their, structure-activity relationships are discussed. Alternative routes for phosphorylation of nucleoside analogs are also reviewed, such as the phosphotransfer capacity of 5'-nucleotidase and protein kinases.

5

Inducible overexpression of cytosolic 5'nucleotidases in mammalian cells

51%

Gazziola C., Moras M., Ferraro P., Rampazzo C., Gallinaro L., Reichard P., Bianchi V.

Cellular and Molecular Biology Letters

|

1999

|

tom 04

|

nr 3

6

Charakterystyka serow topionych pod wzgledem obecnosci dodanych fosforanow oraz zawartosci fosforu, wapnia, magnezu i cynku

38%

Oledzka R., Skrajnowska D., Kazimirska J.

Bromatologia i Chemia Toksykologiczna

|

2004

|

tom 37

|

nr 1

99-104

W pracy oznaczano zawartość fosforu, wapnia, magnezu i cynku oraz określono ich wzajemne relacje w wybranych serach topionych produkcji krajowej. Dokonano jakościowej oceny dodanych mono- i wielofosforanów. Stwierdzono zróżnicowaną zawartość składników mineralnych w zależności od gatunku sera topionego oraz od producenta. Wykazano, że 100 g badanych produktów pokrywa zapotrzebowanie na ok. 97,4% fosforu, 74,6% wapnia, 8,2% magnezu i 14,1% cynku dla osób dorosłych.

7

Effects of starch chemical structures on gelatinization and pasting properties

38%

Chen Y. Y., Mcpherson A. E., Radosavljevic M., Lee V., Wong K. S., Jane J.

Żywność Technologia Jakość. Suplement

|

1998

|

tom 05

|

nr 4

63-71

Ograniczanie wyników

An isotopic assay of dUTPase activity based on coupling with thymidylate synthase

Diminished expression of adenosine kinase in diabetic rats

Acyclic analogues of 5-fluoro-dUMP and 5-fluoro-2'-deoxyuridine: Synthesis and inhibition of thymidylate synthase and tumour cell growth

Stucture-activity relationships for phosphorylation of nucleoside analogs to monophosphates by nucleoside kinases

Inducible overexpression of cytosolic 5'nucleotidases in mammalian cells

Charakterystyka serow topionych pod wzgledem obecnosci dodanych fosforanow oraz zawartosci fosforu, wapnia, magnezu i cynku

Effects of starch chemical structures on gelatinization and pasting properties