Dsb proteins control the formation and rearrangement of disulfide bonds during the folding of secreted and membrane proteins in bacteria. DsbG, a member of this family, has disulfide bond isomerase and chaperone activity. So DsbG was shown to interact with refolding intermediates of chemically denatured citrate synthase and prevents their aggregation in vitro. In addition to sharing sequence homology with the thiol disulfide exchange protein DsbC, DsbG likewise was shown to form a stable periplasmic dimer and it displays an equilibrium constant with glutathione comparable with DsbA and DsbC. DsbG was found to be expressed at approximately 25% the level of DsbC. Recombinant DsbG was expressed in E.coli and purified by conventional chromatography techniques.