Which class of antibiotics inhibits DNA gyrase?

Fluoroquinolones are a class of antibiotics that specifically target and inhibit DNA gyrase, an important enzyme in bacterial DNA replication and transcription. DNA gyrase is responsible for introducing negative supercoils into DNA, which is essential for the proper functioning of bacterial DNA during replication. By inhibiting this enzyme, fluoroquinolones prevent bacterial cells from replicating and dividing, ultimately leading to the death of the bacteria.

In contrast, macrolides primarily work by inhibiting bacterial protein synthesis through binding to the 50S ribosomal subunit, which does not directly impact DNA processes. Penicillins are β-lactam antibiotics that disrupt bacterial cell wall synthesis, and their mechanism is unrelated to DNA gyrase. Similarly, aminoglycosides also inhibit protein synthesis but do so by binding to the 30S ribosomal subunit, further distinguishing their mode of action from that of fluoroquinolones. Thus, the distinct ability of fluoroquinolones to inhibit DNA gyrase makes them the correct choice in this question about antibiotic action.