How do quinolones/ floroquinolones work?

Question

I know they inhibit nucleic acid replication and transcription, but how? Do they interfere with a specific enzyme (helicase, polymerase, ligase etc)?

Ivy Acosta · Accepted Answer

Quinolones are a family of synthetic broad spectrum antibiotic drugs.

A fluorine atom is joined to the central quinolone ring by fluoro quinolones, which are useful in treating severe bacterial infections. By obstructing the DNA replication pathway of bacteria, quinolones and fluoroquinolones prevent them from replicating. Protein synthesis and DNA replication both depend on the unwinding of DNA, which is caused by enzymes of the topoisomerase II type. Quinolones and fluoroquinolones inhibit this enzyme by changing its activate site and preventing it from reacting with its substrate, which stops the bacterium from reproducing or synthesizing proteins. These typically selectively inhibit the topoisomerase II ligase domain, leaving the two nuclease domains intact. Together with the constant action of topoisomerase II in the bacterial cell, this modification leads to DNA fragmentation via the nucleasic activity of the intact enzyme domain. Fluoroquinolones enter the cells through porins and can target intracellular pathogens.

Julian Aguilar · Answer

undefined Quinolones/fluoroquinolones inhibit bacterial DNA gyrase and topoisomerase IV, disrupting DNA replication and repair, leading to bacterial cell death.