Figure 2.

A. Cooperative quinolone–DNA binding model of Shen et al. for the inhibition of the DNA gyrase. Four molecules of quinolones are self‐associated. Quinolones bind to DNA via hydrogen bonds to the unpaired bases.
B. Model of Maxwell et al. for quinolone binding to DNA and GyrA (DNA gyrase) or ParC (Topo IV). Mutations in DNA gyrase or Topo IV that confer quinolone resistance are clustered principally within a small region (QRDR). The most common mutations of the QRDR include Ser‐83 and Asp‐87 for GyrA, or Ser‐80 and Glu‐84 for ParC.