A catalytic dyad modulates conformational change in the CO₂-fixing flavoenzyme 2-ketopropyl coenzyme M oxidoreductase/carboxylase.

ABSTRACT: 2-Ketopropyl-coenzyme M oxidoreductase/carboxylase (2-KPCC) is a member of the flavin and cysteine disulfide containing oxidoreductase family (DSOR) that catalyzes the unique reaction between atmospheric CO₂ and a ketone/enolate nucleophile to generate acetoacetate. However, the mechanism of this reaction is not well understood. Here, we present evidence that 2-KPCC, in contrast to the well-characterized DSOR enzyme glutathione reductase, undergoes conformational changes during catalysis. Using a suite of biophysical techniques including limited proteolysis, differential scanning fluorimetry, and native mass spectrometry in the presence of substrates and inhibitors, we observed conformational differences between different ligand-bound 2-KPCC species within the catalytic cycle. A

SUBMITTER: Mattice JR 

PROVIDER: S-EPMC9062435 | biostudies-literature | 2022 May

REPOSITORIES: biostudies-literature