pathogenic determinants
Last reviewed 11/2022
C. diphtheriae has a number of pathogenic determinants:
- exotoxin:
- a single polypeptide chain of molecular weight 63,000
- enters cell and split into cell-binding domain and active fragment
- carried by a lysogenic phage
- expressed at low cellular free ion concentrations
- the active fragment:
- catalyses the transfer of the ADP-ribose moiety of NAD to a modified histidine residue of elongation factor 2 (EF2) within the cytoplasm
- inactivates EF2, preventing the translocation of peptidyl-tRNA and so inhibiting protein synthesis
- colonization factors
- a number of exoenzymes