Question
Virulence factor for the organism shown in the photomicrograph below ?
A. Endotoxin.
B. Tetanolysin.
C. Tetanospasmin.
D. Bacteremia.
Show Answer
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Correct Answer » C
Explanation
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The organism shown in the photomicrograph above represents clostridium tetani. Virulence factor for clostridium tetani is Tetanospasmin.
Pathogenicity of CI tetani
- Cl. tetani has little invasive property and is confined to the primary site of lodgment.
- Tetanus results from the action of the potent exotoxin it produces.
Toxins of CI tetani
1. Tetanolysin (Hemolysin)
- Not relevant in the pathogenesis of tetanus.
2. Tetanospasmin (neurotoxin)
- In the brainstem and spinal cord it blocks release of the inhibitory neurotransmitter glycine and ‘yaminobutyric acid (GABA).
- It resembles strychnine in its effects, but it acts presynaptically, while strychnine acts postsynaptically.
- Tetanus toxin and botulinum toxin resemble each other in their aminoacid sequences.
3. Nonspasmogenic, peripherally active neurotoxin
