Insight into the Mechanism of Phenylacetate Decarboxylase (PhdB), a Toluene-Producing Glycyl Radical Enzyme.

ABSTRACT: We recently reported the discovery of phenylacetate decarboxylase (PhdB), representing one of only ten glycyl-radical-enzyme reaction types known, and a promising biotechnological tool for first-time biochemical synthesis of toluene from renewable resources. Here, we used experimental and computational data to evaluate the plausibility of three candidate PhdB mechanisms, involving either attack at the phenylacetate methylene carbon or carboxyl group [via H-atom abstraction from COOH or single-electron oxidation of COO^- (Kolbe-type decarboxylation)]. In vitro experimental data included assays with F-labeled phenylacetate, kinetic studies, and tests with site-directed PhdB mutants; computational data involved estimation of reaction energetics using density functional theory (DFT).

SUBMITTER: Rodrigues AV 

PROVIDER: S-EPMC7079210 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature