Bacterial Toxins- Lecture 10/7/21

Question 1

4 Steps for bacterial disease

Answer 1

1. Encounter host
2. Establish an infectious niche
3. Multiply, cause tissue damage
4. Spread to other tissues, hosts, or both

Question 2

Toxin

Answer 2

A protein that damages eukaryotic cells

Question 3

Endotoxins

Answer 3

Non-proteinaceous lipopolysaccharide of gram-negative bacteria, overreaction of host immune response

Question 4

C. Difficile toxin structure (4 domains)

Answer 4

• Enzymatically active domain
• Cysteine protease domain (auto cleaves)
• Hydrophibic region
• Receptor binding carbohydrates

Question 5

Mechanism of C. Difficile

Answer 5

Threads through once early endosome acidifies-> acts on Rho proteins (G protein) which causes cell death

Question 6

Botulism symptom

Answer 6

Clostridium Botulinum causes flaccid paralysis

Question 7

Botulism mechanism of action

Answer 7

Cleaves proteins involved in the real ease of Acetylcholine at synaptic cleft, can’t contract muscles

Question 8

A-B toxin

Answer 8

A unit is enzymatically active

B unit is cell binding, triggers RME

Question 9

Tetanus symptoms

Answer 9

Clostridium tentani causes spastic paralysis

Question 10

Tetanus mechanism of action

Answer 10

Same as botulism, but targets GABA in the CNS which causes overactive contraction

Question 11

Cholera symptoms

Answer 11

A lot of diarrhea

Question 12

Cholera mechanism of action

Answer 12

Secretes AB toxin that locks GI G protein in on position, decreasing Na+ absorption and increases Cl- secretion, leading to mass water secretion