TABLE 5.
Characterization of INH-resistant subcultures derived from INH-exposed culture of H37Rva
| Subculture | AST result by BACTEC | MIC (μg/ml) | Catalase activityb | Mutation in katG product |
|---|---|---|---|---|
| H37Rv control | +++ | None (WTd) | ||
| SC1 | Rc | 0.4 | ++ | None (WT) |
| SC2 | R | >2 | + | None (WT) |
| SC3 | R | >2 | + | D329H |
| SC4 | R | >2 | − | None (WT) |
| SC5 | R | 0.4 | ++ | None (WT) |
| SC6 | R | >2 | − | W328R |
| SC7 | R | >2 | − | W328R |
| SC8 | R | >2 | − | None (WT) |
a
INH-resistant subcultures derived from an INH-exposed H37Rv culture were characterized for level of resistance, catalase activity, and resistance mutations. SC1 to -4 and SC5 to -8 are subcultures derived from INH susceptibility testing vials inoculated with H37Rv containing 0.1 μg/ml and 0.4 μg/ml INH, respectively.
b
The number of + signs indicates relative catalase activity; − indicates no catalase activity.
c
R, resistance.
d
WT, wild type.