How does Flucytosine affect cellular processes?

Flucytosine primarily affects cellular processes by inhibiting DNA and RNA synthesis. This antifungal agent is a pyrimidine analog that is converted within fungal cells to 5-fluorouracil, a compound that disrupts nucleic acid metabolism. Specifically, 5-fluorouracil gets incorporated into RNA, which leads to the formation of faulty proteins that can disrupt essential cellular functions. Moreover, by inhibiting thymidylate synthase, a key enzyme in DNA synthesis, flucytosine effectively reduces the ability of the fungal cell to replicate its genetic material, ultimately hindering its growth and proliferation.

This mechanism is decisive for its effectiveness in treating certain fungal infections, particularly in immunocompromised patients, as it selectively targets fungal cells while having a less potent effect on human cells. Thus, the inhibition of both DNA and RNA synthesis is the cornerstone of how flucytosine exerts its therapeutic action against fungal infections.