Sulfonamides are involved in blocking enzymes required for which process?

Sulfonamides work by mimicking p-aminobenzoic acid (PABA), which is a substrate for the enzyme dihydropteroate synthase in the folic acid synthesis pathway. Folic acid is essential for bacteria because it is necessary for the synthesis of nucleotides, which in turn are crucial for DNA and RNA synthesis. By inhibiting this enzyme, sulfonamides effectively block the production of folic acid, which disrupts the ability of bacteria to grow and reproduce.

The other processes listed involve different mechanisms and substrates. Cell wall synthesis is targeted by beta-lactams like penicillin while protein synthesis is inhibited by antibiotics such as tetracyclines or macrolides. DNA replication is affected by other classes of antibiotics such as quinolones. Overall, sulfonamides specifically inhibit folic acid synthesis, making this the correct choice.