The Sound of Evolution
Sulfisoxazole
Mechanism of action:
Sulfisoxazole is a sulfonamide antibiotic. Structurally, sulfisoxazole resembles para-aminobenzoic acid (PABA), which is an essential precursor for bacterial folic acid synthesis. Sulfisoxazole competitively binds to dihydropteroate synthase in place of para-aminobenzoic acid, thereby blocking the formation of dihydrofolic acid and ultimately interfering with bacterial nucleic acid synthesis.
Reference(s):
1. Jorgensen JH et al. (2005). Susceptibility of Neisseria meningitidis to 16 antimicrobial agents and characterization of resistance mechanisms affecting some agents. J Clin Microbiol.
2. Fiebelkorn KR et al. (2005). Mutations in folP associated with elevated sulfonamide MICs for Neisseria meningitidis clinical isolates from five continents. Antimicrob Agents Chemother.
3. Hong YL et al. (1995). Inhibition of recombinant Pneumocystis carinii dihydropteroate synthetase by sulfa drugs. Antimicrob Agents Chemother.