TABLE 5.
Cleavage with parent and mutant S. aureusa topoisomerase IV (GrlA alteration)
| Strain | Minimum concn (μM) of quinolone required to induce cleavage with topoisomeraseb IV
|
||||
|---|---|---|---|---|---|
| Trovafloxacin | Ciprofloxacin | Levofloxacin | Sparfloxacin | Pefloxacin | |
| S. aureus parent | 0.036 | 0.16 | 0.62 | 0.28 | 1.18 |
| 4220-19 (GrlA; Phe80) | 0.99 | 3.9 | 15 | 11.25 | 35 |
| 4220-16 (GrlA; Lys84) | 1.11 | 3.3 | 10 | 11.7 | 30 |
a
Mutant 4220-19, Ser80 to Phe; mutant 4220-16, Glu84 to Lys.
b
Values are means of multiple assays; standard deviations are ≤20% of the mean.