Which antibiotic class inhibits folic acid production in bacteria?

The class of antibiotics that inhibits folic acid production in bacteria is sulfa drugs. These drugs, also known as sulfonamides, work by mimicking para-aminobenzoic acid (PABA), a substrate for the bacterial synthesis of folate. Folic acid is crucial for the production of nucleic acids and is necessary for DNA synthesis and cell division in bacteria. By inhibiting the enzyme dihydropteroate synthase, sulfa drugs prevent the conversion of PABA to folate, effectively starving the bacteria of this essential nutrient and hindering their growth and replication.

Other antibiotic classes do not primarily target folic acid synthesis. For instance, fluoroquinolones inhibit bacterial DNA gyrase and topoisomerase IV, key enzymes involved in DNA replication. Tetracyclines disrupt protein synthesis by binding to the bacterial ribosome, while beta-lactam antibiotics target the bacterial cell wall synthesis by inhibiting penicillin-binding proteins. Each of these mechanisms is distinct and does not involve the metabolic pathway of folic acid production. This specificity in action helps to explain why sulfa drugs are recognized for their role in inhibiting folic acid synthesis in bacteria.