Acyclovir requires activation by which enzyme to become active against herpes simplex virus?
Answer and explanation
Correct answer: B. Viral thymidine kinase
- Step 1: Acyclovir is a guanosine analog that is first phosphorylated by viral thymidine kinase. Step 2. Human enzymes then make the active triphosphate, which stops viral DNA polymerase. Answer: viral thymidine kinase. Why not the others: the other enzymes are not the activating step, which is why acyclovir spares uninfected cells.
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