Question

Think of the FO as inhibiting FOlic Acid Synthesis. What is the mechanism of action of Folic Acid Synthesis Inhibitors?

1) Competitive inhibition of dihydrofolate reductase
2) Non-competitive inhibition of dihydrofolate reductase
3) Inhibition of thymidylate synthase
4) Inhibition of DNA polymerase

Answer 1

Folic acid synthesis inhibitors act through competitive inhibition of dihydrofolate reductase, preventing the conversion of folic acid to tetrahydrofolic acid necessary for DNA and RNA synthesis. Drugs such as methotrexate and trimethoprim are typical competitive inhibitors of this enzyme.

Step-by-step explanation:

The mechanism of action of Folic Acid Synthesis Inhibitors involves:

1) Competitive inhibition of dihydrofolate reductase

Folic Acid Synthesis Inhibitors, like sulfonamides or trimethoprim, function by competitively inhibiting dihydrofolate reductase, a critical enzyme in the folate metabolic pathway. This inhibition prevents the conversion of dihydrofolate to tetrahydrofolate, a form essential for the synthesis of nucleic acids (DNA and RNA) and important for cell division and growth.

By interfering with the synthesis of tetrahydrofolate, these inhibitors disrupt the production of nucleic acids in microbial cells, inhibiting their ability to replicate and grow. This mechanism selectively targets microbial cells while minimizing adverse effects on human cells, making these inhibitors valuable in the treatment of various bacterial infections.