TABLE 2.
Phenotypic and genotypic characteristics of C. difficile mutants obtained after selection by MX
| Parent strain | Mutants selected | Step of selection (μg/ml MX) | MIC (μg/ml)
|
Substitution(s) in:
|
|||
|---|---|---|---|---|---|---|---|
| Agar dilution method for:
|
Etest for GA | ||||||
| MX | LE | GyrA | GyrB | ||||
| C253 | C253 a, b, c | I (2) | 2 | 4 | 1 | ||
| C253 d, e, f | II (4) | 4 | 4 | 1 | |||
| C253 g, h, i | III (8) | 16 | 64 | 8 | Ala118 to Ser | ||
| CD5 | CD5 a, b, c | I (2) | 2 | 2 | 0.75 | Ser416 to Ala | |
| CD5 d, e, f | II (4) | 4 | 2 | 0.75 | Ser416 to Ala | ||
| CD5 1-g, h, i | III (8) | 8 | 16 | 3 | Ala92 to Glu | Ser416 to Ala | |
| CD5 2-g, h, i | III (8) | 16 | 64 | 16 | Ala118 to Ser/Thr82 to Ala | Ser416 to Ala | |
| A422 | A422 a, b, c | I (2) | 2 | 4 | 1.5 | ||
| A422 d, e, f | II (4) | 4 | 4 | 1.5 | |||
| A422 g, h, i | III (8) | 32 | 64 | ≥32 | Asp81 to Asn | ||
| 630 | 630 a, b, c | I (2) | 2 | 4 | 0.75 | ||
| 630 d, e, f | II (4) | 4 | 4 | 2 | |||
| 630 g, h, i | III (8) | 16 | 64 | ≥32 | Asp426 to Val | ||
| BI2 | BI2 a, b, c | I (2) | 16 | 8 | 1.5 | Arg447 to Lys | |
| BI2 d, e, f | II (32) | 128 | 64 | 6 | Arg447 to Lys/Asp426 to Asn | ||