Acyclovir - An Antiviral Agent Flashcards
What is the role of thymidine kinase in viral DNA synthesis?
Synthesis of the protein coat
What nucleoside is acyclovir similar to?
Deoxyguanosine
How is acyclovir activated?
Inactive acyclovir is added.
Viral thymidine kinase has a high affinity for acyclovir and converts it to acycloGMP.
Host guanyate kinases convert this to acycloGDP.
Host phosphotransferases convert this to acycloGTP.
AcycloGTP is the active form and has a high affinity for viral DNA polymerase.
How does acyclovir prevent viral DNA synthesis?
It is a chain terminator and does not have a free 3’ hydroxyl group for dNTPs to bind to once incorporated into the chain.
Why does acyclovir only target infected cells and not normal host cells?
It needs viral thymidine kinase to be activated.
Why is acycloGTP not incorporated into host DNA?
It has a higher affinity for viral DNA polymerases.
What can acyclovir be used to treat?
Herpes cold sores in form of Zovirax.
Varicella zoster virus (chicken pox).
Herpes viruses.
Immunosuppressed.
