Exotoxins in disease

Although bacterial growth and invasiveness can challenge the body's defenses and impair normal function, often the symptoms of a bacterial infection are due to the production of specific exotoxins. An exotoxin is a protein molecule (with one or more subunits) that is secreted by bacteria at the site of infection. The secreted toxin may act locally or systemically via the bloodstream. Exotoxins generally fall into several types:

Pathogen Exotoxin Effect
Bacillus anthracis Edema factor cAMP = edema
Lethal factor Kills cell
Bordetella pertussis Pertussis toxin (PTx) Inactivates G-protein = cAMP
Clostridium botulinum Botulinum toxin (botox) Acetylcholine release = flaccid paralysis
Clostridium tetani Tetanus toxin Inhibitory neurotransmitter release = spastic paralysis
Corynebacterium diphtheriae Diphtheria toxin Binds EF-2, protein synthesis = cell death
ETEC Heat -labile enterotoxin (LT-I) same as CTx
Heat-stable enterotoxin (STa) increases cGMP = fluid hypersecretion
EHEC Shiga toxins (STx-1 and STx-2) protein synthesis = fluid absorption; cell death; glomerular damage = HUS
Pseudomonas aeruginosa Exotoxin A Same as DTx
Shigella dysenteriae Shiga toxin (STx) protein synthesis = fluid absorption; cell death
Shigella spp. Shiga-like toxin similar to ST
Staphylococcous aureus Toxic shock syndrome toxin (TSST) superantigen
Staphylococcal enterotoxin superantigen
Streptococcus pyogenes Streptococcal pyrogenic exotoxin (Spe) superantigen
Vibrio cholerae Cholera toxin (CTx) cAMP = fluid secretion & diarrhea