Direct electrochemical analyses of a thermophilic thioredoxin reductase: interplay between conformational change and redox chemistry.

ABSTRACT: Thioredoxin reductases (TrxRs) are flavin-containing dithioloxidoreductases that couple reduction equivalents from the soluble NAD(P)H pool to the soluble protein thioredoxin (Trx). Previous crystallographic studies of the Escherichia coli enzyme ( ecTrxR) have shown that low molecular weight TrxRs can adopt two distinct conformations: the first (FO) is required for the oxidation of the flavin cofactor and the generation of reduced Trx; the second (FR) is adopted for the reduction of the flavin by NAD(P)H. Here, protein electrochemistry has been used to interrogate the equilibrium between the oxidized and reduced conformations of the ecTrxR and a novel, low molecular weight TrxR from the thermophilic archaeon Thermoplasma acidophilum ( taTrxR) that is characterized structurally and biochem

SUBMITTER: Hamill MJ 

PROVIDER: S-EPMC3982938 | biostudies-literature | 2008 Sep

REPOSITORIES: biostudies-literature