Question

What is the diphtheria toxin?

Answer 1

Diphtheria toxin:

1. Diphtheria is a dangerous infection caused by bacteria called Corynebacterium diphtheriae, which produce a toxin (poison).
2. It can cause breathing difficulties, heart failure, paralysis, and even death.
3. The diphtheria toxin, a bacterial exotoxin of the A/B prototype, is produced by Corynebacterium diphtheriae.
4. Diphtheria toxin (DT) is a Corynebacterium diphtheriae extracellular protein that inhibits protein synthesis and kills sensitive cells.
5. It comprises two parts: subunit A and subunit B.
6. Subunit A – includes the enzymatic activity to block the elongation of factor-2, which is involved in the production of host proteins.
7. Subunit B is in charge of interacting with the membrane of a vulnerable host cell.
8. It has a T (translocation) domain that inserts into the endosome membrane, allowing the enzyme component to escape into the cytoplasm.