Bacterial Exotoxins

Question 1

Diphtheria toxin

Answer 1

1. Classification: ADP-ribosylation
2. Action: inhibits protein synthesis
3. Bacteria: Corynebacterium diphtheriae

Question 2

Cholera toxin

Answer 2

1. Classification: ADP-ribosylation
2. Action: Increases adenylate cyclase activity
3. Bacteria: Vibrio cholerae

Question 3

Pertussis toxin

Answer 3

1. Classification: ADP-ribosylation
2. Action: Increases adenylate cyclase activity
3. Bacteria: Bordetella pertussis

Question 4

Anthrax toxin (edema factor)

Answer 4

1. Classification: ADP-ribosylation
2. Action: Increases adenylate cyclase activity
3. Bacteria: Bacillus anthracis

Question 5

Heat-labile toxin

Answer 5

1. Classification: ADP-ribosylation
2. Action: Increases adenylate cyclase activity
3. Bacteria: E. coli

Question 6

TSST

Answer 6

1. Classification: superantigen
2. Action: binds to both class II MHC and T-cell receptors -> release of cytokines from Th-cells
3. Bacteria: Staph. aureus

Question 7

Erythrogenic toxin

Answer 7

1. Classification: superantigen
2. Action: binds to both class II MHC and T-cell receptors -> release of cytokines from Th-cells
3. Bacteria: Strep. pyogenes

Question 8

Tetanus toxin

Answer 8

1. Classification: protease
2. Action: neurotoxin, inhibits glycine NT
3. Bacteria: Clostridium tetani

Question 9

Botulinum toxin

Answer 9

1. Classification: protease
2. Action: neurotoxin, inhibits Ach at synapse
3. Bacteria: Clostridium botulinum

Question 10

Anthrax toxin (lethal factor)

Answer 10

1. Classification: protease
2. Action: cleaves phosphokinase
3. Bacteria: Bacillus anthracis

Question 11

Exfoliatin

Answer 11

1. Classification: protease
2. Action: cleaves desmoglein
3. Bacteria: Staph. aureus

Question 12

a-toxin

Answer 12

1. Classification: lecithinase
2. Action: cleaves lecithin in cell membrane
3. Bacteria: Clostridium perfringens