Altered order of substrate binding by DNA polymerase X from African Swine Fever virus.

ABSTRACT: A sequential ordered substrate binding established previously for several DNA polymerases is generally extended to all DNA polymerases, and the characterization of novel polymerases is often based on the assumption that the enzymes should productively bind DNA substrate first, followed by template-directed dNTP binding. The comprehensive kinetic study of DNA polymerase X (Pol X) from African swine fever virus reported here is the first analysis of the substrate binding order performed for a low-fidelity DNA polymerase. A classical steady-state kinetic approach using substrate analogue inhibition assays demonstrates that Pol X does not follow the bi-bi ordered mechanism established for other DNA polymerases. Further, using isotope-trapping experiments and stopped-flow fluorescence assays, w

SUBMITTER: Kumar S 

PROVIDER: S-EPMC2652249 | biostudies-literature | 2008 Jul

REPOSITORIES: biostudies-literature