PetriKey

Antimicrobial

Nucleoside analog antivirals

Fake nucleosides cause chain termination

NOO-klee-oh-side AN-uh-logz

antiviralnucleoside-analogchain-terminationmechanismherpesvirus

High-yield clue

A nucleoside analog lacking a 3'-hydroxyl gets built into the viral chain and terminates further elongation.

Overview

An antiviral class (e.g. acyclovir, ganciclovir) that mimics natural nucleosides and is incorporated into growing viral nucleic acid, used in coursework to teach selective activation and chain termination.

Classification

  • Antiviral
  • Nucleoside/nucleotide analog
  • Requires phosphorylation to active form
  • Inhibits viral polymerase

Lab & identification clues

  • Acyclovir activation depends on viral thymidine kinase vocabulary
  • Chain termination = missing 3'-OH group concept
  • Selective toxicity from preferential viral-enzyme activation

Associations

  • Herpesvirus study association (HSV, VZV, CMV)
  • Viral DNA polymerase target vocabulary
  • Resistance via thymidine-kinase or polymerase mutation framing

Commonly confused with

  • Reverse transcriptase inhibitors (NRTIs)
  • Neuraminidase inhibitors

Your notes

Original mechanism summary for microbiology study. Sources checked: CDC antimicrobial-resistance guidance, NCBI Bookshelf Medical Microbiology, and standard coursework frameworks; reviewed 2026-06. Covers class, mechanism, and resistance vocabulary only; no prescribing, dosing, or patient-specific treatment guidance.

CDC: CDC antimicrobial resistance overview and threat reportssourceWHO: WHO bacterial priority pathogens list 2024sourceNCBI Bookshelf: Medical Microbiology antimicrobial mechanism foundationssource