Destabilization of a bovine B12 trafficking chaperone protein by oxidized form of glutathione

► Binding of GSSG destabilizes bCblCpro, the bovine B12 trafficking chaperone protein. ► Binding of GSSG induces conformational changes of bCblCpro. ► The binding affinity for GSSG is similar with the affinity for GSH. ► The molar ratio of GSH/GSSG would determine the stability of bCblCpro.