The functional properties of DsbG, a thiol-disulfide oxidoreductase from the periplasm of Escherichia coli

Genetic studies have recently identified DsbG, a new member of the dsb group of redox proteins, which catalyze protein disulfide bond formation in the periplasm of Escherichia coli. We now demonstrate that DsbG functions primarily as an oxidant during protein disulfide bond formation, which is consistent with the low stability of its active site disulfide bond, There are indications, however, that the substrate range of DsbG mag be narrower than the other periplasmic oxidative enzymes, DsbA and DsbC. Our observations further elaborate the pathway of disulfide bond formation in E. coli. (C) 1998 Federation of European Biochemical Societies.