TABLE 2.
Mutational analysis of the PmrAB regulatory pathwaya
| Strain | CST concn used for selection (mg/liter) | PmrA (224 aa) response regulator (aa 4–113) | PmrB (444 aa) |
CST MIC (mg/liter) |
Population analysis profile | ||||
|---|---|---|---|---|---|---|---|---|---|
| aa 1–217 | HisK (aa 218–279) | aa 278–325 | HATpaseC (aa 326–436) | BMD | Etest | ||||
| Ab1 | 0 | 2 | 0.125 | S | |||||
| Ab1-2-R1 | 2 | M308R | 2 | 0.25 | HR | ||||
| Ab1-8-R1 | 8 | S144KLAGS | 2 | 0.38 | HR | ||||
| Ab2 | 0 | 2 | 0.19 | S | |||||
| Ab2-1-R1 | 1 | M12I | 2 | 0.25 | HR | ||||
| Ab2-1-R4 | 1 | T235I | 8 | 6 | R | ||||
| Ab2-32-R1 | 32 | A226T | 8 | 4 | R | ||||
| Ab2-32-R3 | 32 | P170L | 2 | 0.38 | HR | ||||
| Ab3 | 0 | 2 | 0.25 | S | |||||
| Ab3-2-R1 | 2 | P233S | 16 | 8 | R | ||||
| Ab3-16-R1 | 16 | P233S | 8 | 4 | R | ||||
a
aa, amino acids; CST, colistin; BMD, broth microdilution; S, susceptible; R, resistant; HR, heteroresistant.