Determining the catalytic role of remote substrate binding interactions in ketosteroid isomerase.

ABSTRACT: A fundamental difference between enzymes and small chemical catalysts is the ability of enzymes to use binding interactions with nonreactive portions of substrates to accelerate chemical reactions. Remote binding interactions can localize substrates to the active site, position substrates relative to enzymatic functional groups and other substrates, trigger conformational changes, induce local destabilization, and modulate an active site environment by solvent exclusion. We investigated the role of remote substrate binding interactions in the reaction catalyzed by the enzyme ketosteroid isomerase (KSI), which catalyzes a double bond migration of steroid substrates through a dienolate intermediate that is stabilized in an oxyanion hole. Comparison of a single-ring and multiple-ring substrat

SUBMITTER: Schwans JP 

PROVIDER: S-EPMC2732871 | biostudies-literature | 2009 Aug

REPOSITORIES: biostudies-literature