Thiol:disulphide interchange protein DsbA/DsbL (IPR023205)

Short name: DsbA/DsbL

Overlapping homologous superfamilies

Family relationships


Bacterial Disulfide bond forming (Dsb) proteins facilitate proper folding and disulfide bond formation of periplasmic and secreted proteins [PMID: 15546661].

Thiol:disulphide interchange proteins DsbA and DsbL are involved in disulfide-bond formation [PMID: 12524212, PMID: 11967064]. They act by transferring its disulfide bond to other proteins and are reduced in the process. DsbA is required for disulfide bond formation in some periplasmic proteins such as PhoA or OmpA and is reoxidised by DsbB [PMID: 21241169, PMID: 18082634]. DsbA is a monomeric thiol disulfide oxidoreductase protein containing a redox active CXXC motif imbedded in a TRX fold. It is involved in the oxidative protein folding pathway in prokaryotes, and is the strongest thiol oxidant known, due to the unusual stability of the thiolate anion form of the first cysteine in the CXXC motif [PMID: 9099998]. The highly unstable oxidized form of DsbA directly donates disulfide bonds to reduced proteins secreted into the bacterial periplasm. This rapid and unidirectional process helps to catalyze the folding of newly-synthesized polypeptides. To regain catalytic activity, reduced DsbA is then reoxidized by the membrane protein DsbB, which generates its disulfides from oxidized quinones, which in turn are reoxidized by the electron transport chain [PMID: 14739460]. DsbL is reoxidised by DsbI; DsbL and DsbI represent a second redox couple in some bacteria for specific substrates [PMID: 18565543].


Contributing signatures

Signatures from InterPro member databases are used to construct an entry.