A conserved sequence motif in the Escherichia coli soluble FAD-containing pyridine nucleotide transhydrogenase is important for reaction efficiency.

ABSTRACT: Soluble pyridine nucleotide transhydrogenases (STHs) are flavoenzymes involved in the redox homeostasis of the essential cofactors NAD(H) and NADP(H). They catalyze the reversible transfer of reducing equivalents between the two nicotinamide cofactors. The soluble transhydrogenase from Escherichia coli (SthA) has found wide use in both in vivo and in vitro applications to steer reducing equivalents toward NADPH-requiring reactions. However, mechanistic insight into SthA function is still lacking. In this work, we present a biochemical characterization of SthA, focusing for the first time on the reactivity of the flavoenzyme with molecular oxygen. We report on oxidase activity of SthA that takes place both during transhydrogenation and in the absence of an oxidized nicotinamide cofactor as

SUBMITTER: Partipilo M 

PROVIDER: S-EPMC9460512 | biostudies-literature | 2022 Sep

REPOSITORIES: biostudies-literature