Substrate induced population shifts and stochastic gating in the PBCV-1 mRNA capping enzyme.

ABSTRACT: The 317 residue PBCV-1 mRNA capping enzyme catalyzes the second enzymatic reaction in the formation of an N-7-methyl-GMP cap on the 5'-end of the nascent mRNA. It is composed of two globular domains bound by a short flexible peptide linker, which have been shown to undergo opening and closing events. The small size and experimentally demonstrated domain mobility make the PBCV-1 capping enzyme an ideally suited model system to explore domain mobility in context of substrate binding. Here, we specifically address the following four questions: (1) How does substrate binding affect relative domain mobility: is the system better described by an induced fit or population shift mechanism? (2) What are the gross characteristics of a conformation capable of binding substrate? (3) Does "domain gatin

SUBMITTER: Swift RV 

PROVIDER: S-EPMC2837470 | biostudies-literature | 2009 Apr

REPOSITORIES: biostudies-literature