thymidine phosphorylase;
thymidine derivatives;
substrate specificity;
inhibitors;
analysis in terms of steric interactions;
D O I:
10.1134/S0006297907010026
中图分类号:
Q5 [生物化学];
Q7 [分子生物学];
学科分类号:
071010 ;
081704 ;
摘要:
Substrate specificity of Escherichia coli thymidine phosphorylase to thymidine derivatives modified at 5'-, 3'-, and 2',3'-positions of the sugar moiety was studied. Equilibrium and kinetic constants (K (m), K (I), k (cat)) of the phosphorolysis reaction have been determined for 20 thymidine analogs. The results are compared with X-ray and molecular dynamics data. The most important hydrogen bonds in the enzyme-substrate complex are revealed.