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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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Mechanism of action of quinolones is:
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The correct answer is  Mechanism of action of Fluoroquinolones
The FQs inhibit the enzyme bacterial DNA gyrase (primarily active in gram negative bacteria), which nicks double-stranded DNA, introduces negative supercoils and then reseals the nicked ends. This is necessary to prevent excessive positive supercoiling of the strands when they separate to permit replication or transcription.
Reference: Essentials of Medical Pharmacology Eighth Edition KD TRIPATHI page no 760