Micro Toxins

Protein Synthesis Inhibitors

100

This Gram-positive rod produces a toxin that inactivates EF-2 via ADP-ribosylation.

Corynebacterium diphtheriae — diphtheria toxin

200

This Gram-negative rod produces Exotoxin A, which has the same mechanism as diphtheria toxin.

Pseudomonas aeruginosa (inactivates EF-2 via ADP ribosylation)

300

This toxin produced by Shigella dysenteriae inactivates the 60S ribosome by cleaving rRNA

Shiga toxin

400

This E. coli strain produces a Shiga-like toxin, leading to bloody diarrhea and HUS

EHEC O157:H7

500

This pathogen produces Pneumolysin and IgA protease, but its capsule is the main virulence factor against phagocytosis

Streptococcus pneumoniae — capsule

cAMP Toxins

100

This toxin from ETEC increases cAMP via activation of Gs, causing watery diarrhea.

Heat-labile toxin

200

This ETEC toxin increases cGMP, decreasing NaCl reabsorption

Heat-stable toxin

300

This Gram-negative curved rod produces a toxin that permanently activates Gs → ↑ cAMP → rice-water diarrhea

Vibrio cholerae — cholera toxin

400

This Gram-positive rod produces Edema Factor, an adenylate cyclase

Bacillus anthracis

500

This toxin disables Gi proteins, increasing cAMP in host cells

Bordetella pertussis — pertussis toxin

Neurotoxins

100

This toxin blocks release of GABA and glycine from inhibitory interneurons

Clostridium tetani — tetanospasmin

200

This toxin blocks release of acetylcholine at the neuromuscular junction

Clostridium botulinum — botulinum toxin

300

This bacterium is acid-fast, and survives inside macrophages using sulfatides

Mycobacterium tuberculosis

400

This Streptococcus produces M protein that leads to molecular mimicry and rheumatic fever

Streptococcus pyogenes 

500

This Streptococcus virulence factor lyses RBCs and WBCs and is the target of ASO antibodies

Streptolysin O

Superantigens & Immune Modulators

100

This staphylococcal toxin is responsible for toxic shock syndrome.

TSST-1

200

This staphylococcal toxin causes scalded skin syndrome by cleaving desmoglein

Exfoliative toxin

300

This streptococcal exotoxin is a superantigen causing scarlet fever and toxic shock–like syndrome

Spe A/C — Streptococcus pyogenes exotoxin

400

This endotoxin’s Lipid A component triggers macrophages to release TNF-α and IL-1, leading to septic shock

Gram-negative bacteria LPS

500

This bacterium produces a superantigen responsible for scalded skin syndrome by cleaving desmoglein-1

Staphylococcus aureus (Exfoliative toxin

Diarrheal & Cytoskeletal Toxins

100

This toxin from Clostridium difficile causes mucosal necrosis and watery diarrhea

Toxin A

200

This toxin disrupts actin cytoskeleton and contributes to pseudomembranous colitis

Toxin B — Clostridium difficile

300

This Gram-negative rod causes bloody diarrhea by actin polymerization (“actin rockets”

Shigella species

400

This heat-labile toxin increases cAMP levels by permanently activating adenylate cyclase, leading to profuse watery diarrhea often associated with travel

Enterotoxigenic Escherichia coli (LT toxin)

500

This bacterium’s capsule and biofilm-forming alginate contribute to chronic pneumonia in cystic fibrosis patients

Pseudomonas aeruginosa — alginate capsule