Reverse antibiotics’ may be found for any of the extant antibiotics
whose target of action is the enzyme essential for the viability
of bacteria. Since only a certain degree of conformational change
would be acceptable for the vital enzyme, a limited number and
kinds of mutations would be allowed to occur. GyrA may be a typical
example. In this study, only three patterns of gyrA mutations were
found in the 59 quinolone-resistant S. aureus strains, and all had
gyrA(Ser84Leu) in common