Lecture 6:

Question 1

what are the 4 faces of clostridium botulinum

Answer 1

1. intoxication (ingestion or injection)
2. infant botulism (ingestion and intestinal proliferation of the organism, internal production of the toxin - infection)
3. wound botulism - deep wound results in anaerobic environment
4. bioterrorism

Question 2

BoNT is an ___ toxin that consists of what 2 subunits

Answer 2

AB toxin that consists of subunits A and B

Question 3

T or F: botulism neurotoxin is inactive after production

Answer 3

True

Question 4

what are the two types of Cb

Answer 4

1. proteolytic: the bacteria produce the protease that activates the neurotoxin
2. non proteolytic: the hosts stomach acids cleave the toxin (activating it)

Question 5

following the ingestion of BoNT molecules are absorbed in the ____ and spread via the ____

Answer 5

gut, blood to the peripheral nerves

Question 6

explain the process whereby the botulinum toxin may cause flaccid paralysis following ingestion

Answer 6

1. following ingestion & production of the toxin molecules are absorbed in the gut and spread via the blood to the peripheral nerves.
2. Normally the axon terminal of the neuron connects with muscle tissues through snare proteins and releases acetylcholine into the muscle cells which causes contraction.
3. BoNT acts as a protease cleaving the snare proteins. This deprives the muscle of acetylcholie signal and results in flaccid paralysis.
4. major issue for lung and heart muscles.

Question 7

human illness is generally caused by what strains of Cb

Answer 7

group 1 and 2
Group 1: C. botulinum A and proteolytic strains of B and F (Human)
Group 2: C. botulinum E and non-proteolytic strains of B and F (Human)