Diphtheria Toxin CRM197 mutant from Corynebacterium diphtheriae

Diphtheria toxin CRM197 mutant from C. diphtheriae is an inactive and non-toxic version of diphtheria toxin. It contains a single base change in the structural gene resulting in the substitution of glutamic acid for glycine which blocks ADP-ribosylation.1 Diphtheria toxin CRM197 mutant has no enzymatic activity but is immunologically indistinguishable from diphtheria toxin. Formulations containing diphtheria toxin CRM197 mutant have been used as carriers of conjugated polysaccharides in the development of vaccines against encapsulated bacterial pathogens.2WARNING This product is not for human or veterinary use.

[1] A.M. PAPPENHEIMER JR.  Annabel A H  Tsuyoshi Uchida. An immunological study of the diphtheria toxin molecule[J]. Immunochemistry, 1972, 9 9: Pages 891-906, IN5-IN6. DOI: 10.1016/0019-2791(72)90163-2
[2] B. BENAISSA-TROUW. Synthetic Polysaccharide Type 3-Related Di-, Tri-, and Tetrasaccharide–CRM197 Conjugates Induce Protection against Streptococcus pneumoniae Type 3 in Mice[J]. Infection and Immunity, 2001, 69 1: 4698-4701. DOI: 10.1128/iai.69.7.4698-4701.2001