Toxin targets + sepsis

Question 1

Toxins

Answer 1

Poisonous substances produced by microorganism

Question 2

2 classes of toxins

Answer 2

Endotoxins + Exotoxins

Question 3

Exotoxins

Answer 3

Produced by anaerobic gram-positive
High toxicity
Secrete enzymes and accessory proteins from living bacteria

Question 4

Endotoxins

Answer 4

Produced by gram-negative
Breakdown products of the cell wall
Non-specific
Low toxicity but immunogenic (able to cause an immune response)

Question 5

Exotoxin symptom

Answer 5

Botulism
Whoopy cough
Cholera
Dysentry (type of gastroenteritis including blood + diarrhoea)

Question 6

Classes of exotoxin

Answer 6

Enzyme mechanism
Cellular target
Molecular target

Question 7

What are the neurotoxins

Answer 7

Botulinum toxin

Tetanus toxin

Question 8

Botulinum toxin

Answer 8

• zinc metalloproteases that cleave snare proteins to pre-synaptic terminals
• prevent vesicle fusion therefore acetylcholine is not released
• act on acetylcholine releasing cells

Question 9

What does Botulinum toxin act on

Answer 9

Acetylcholine releasing cells

Question 10

What does Tetanus toxin act on

Answer 10

Glycine + GABA releasing cells

Question 11

GPCR - targeting toxins

Answer 11

Cholera toxin

Pertussis toxin

Question 12

Toxin - targeting toxins

Answer 12

Clostridium sp. Toxins
Clostridum difficile toxins A + B
- both inhibit actin polymerisation

Question 13

Cholera toxin

Answer 13

ADP-ribosyltransferase adds ADP-ribose moiety to alpha subunits of heterotrimeric G proteins
Persistent activation of adenylyl cyclase by activation of Gs