... 2035 Bacitracin inhibits the reductive activity of protein disulfide isomerase by disulfide bond formation with free cysteines in the substrate-binding domain Nina Dickerhof1, Torsten Kleffmann2, ... Ruddock LW, Darby NJ & Freedman RB(1998) The b domain provides the principal peptide-binding site of protein disulde isomerase but alldomains contribute to binding of misfolded proteins.EMBO ... thiazoline ring of bacitracin A and Cys345are shown as chemical structures, the rest of bacitracin A as Bacitracin A’, and all other amino acids not involved in the crosslink by the sin-gle-letter...