This Diphtheria toxin CRM197 was highly purified from growth media of Corynebacterium diphtheriae mutant CRM197. CRM197 like wild-typediphtheria toxin is a single polypeptide chain of 535 amino acids (58 kD) consisting of two subunits linked by disulfide bridges. Binding to the cell surface of the less stable of these two subunits allows the more stable part of the protein to penetrate the host cell. Wild-type toxin catalyzes the ADP-ribosylation of eucaryotic elongation factor-2 (eEF2) by using NAD, thus inactivating this protein. However, CRM197 has an alteration of 52nd Gly to Glu and it has no ADP ribosylation activity nor toxicity to cells.
Diphtheria Toxin mutant CRM197
To be used for research only. DO NOT use for human gene therapy or clinical diagnosis.