Sulfadiazine is a sulfonamide antibacterial agent with a broad spectrum of activity against gram-positive and gram-negative bacteria. It functions primarily by inhibiting bacterial folic acid synthesis, which is crucial for the production of nucleotides, the building blocks of DNA.
Mechanism of Action:
Competitive Inhibition: Sulfadiazine is structurally similar to para-aminobenzoic acid (PABA), a substrate necessary for bacterial synthesis of dihydrofolic acid. By competing with PABA, sulfadiazine inhibits dihydropteroate synthetase, an enzyme that is crucial for the conversion of PABA to dihydrofolic acid.
Folic Acid Synthesis Inhibition: This inhibition prevents the bacteria from synthesizing folic acid, ultimately leading to the cessation of bacterial growth and replication.
