Crystal structure and biophysical properties of Bacillus subtilis BdbD. An oxidizing thiol:disulfide oxidoreductase containing a novel metal site.

ABSTRACT: BdbD is a thiol:disulfide oxidoreductase (TDOR) from Bacillus subtilis that functions to introduce disulfide bonds in substrate proteins/peptides on the outside of the cytoplasmic membrane and, as such, plays a key role in disulfide bond management. Here we demonstrate that the protein is membrane-associated in B. subtilis and present the crystal structure of the soluble part of the protein lacking its membrane anchor. This reveals that BdbD is similar in structure to Escherichia coli DsbA, with a thioredoxin-like domain with an inserted helical domain. A major difference, however, is the presence in BdbD of a metal site, fully occupied by Ca(2+), at an inter-domain position some 14 A away from the CXXC active site. The midpoint reduction potential of soluble BdbD was determined as -75 mV

SUBMITTER: Crow A 

PROVIDER: S-EPMC2749146 | biostudies-literature | 2009 Aug

REPOSITORIES: biostudies-literature