Mechanism of action of ciprofloxacin in gram negative bacteria:-: (A) Inhibition of mycolic acid, (B) Inhibition of topoisomerase IV, (C) Inhibition of DNA gyrase, (D) Inhibition of helicase
Answer is C. MECHANISM OF FLUOROQUINOLONES (FQ) In gram negative bacteria, FQ inhibit DNA gyrase by binding to its A subunit and interfere with cutting and resealing function. In gram positive bacteria, FQ inhibit similar enzyme DNA topoisomerase IV.