TABLE 7.
Characterization of mutants from step selections undertaken with strains exhibiting resistance to rifamycin and/or quinolone agents
| Strain | Selectiona | Relevant genotyped | MIC (μg/ml)
|
||||
|---|---|---|---|---|---|---|---|
| CBR-2092
|
Rifampin | Ciprob | EtBrc | ||||
| Broth | Agar | ||||||
| CB1884 | Parent | rpoBR484HgyrAΔL520, S84LparCR236,†H103Y | 64 | 4 | >250 | 8 | 2 |
| CB1887 | CB1884 plus 20 days selection with ABT-719 | rpoBR484HgyrAΔL520, S84L, E88KparCR236,†H103Y, S80Y, E84G | >250 | >8 | >250 | 64 | ND |
| CB370 | Parent | rpoBH481Y | 0.12 | 0.03 | >250 | 0.25 | 4 |
| CB1947 | CB370 plus 20 days selection with CBR-2092 | rpoBH481YgyrAS84L, ΔE697parCG167V | 4 | 1 | >250 | 2 | 4 |
| CB814 | Parent | rpoBWTgyrAS84LparCS80F | 0.015 | 0.06 | 0.008 | 16 | 4 |
| CB1952 | CB814 plus 21 days selection with CBR-2092 | rpoBS486LgyrAS84L, E88Q, G532SparCS80F, E84L | 31 | 4 | >250 | 64 | 4 |
| CB815 | Parent | rpoBH481YgyrAS84LparCS80F | 1 | 0.25 | >125 | 16 | 4 |
| CB1953 | CB815 plus 7 days selection with CBR-2092 | rpoBH481YgyrAS84L, V598IparCS80F, R570H | 16 | 2 | >125 | 64 | 4 |
| CB1954 | CB815 plus 7 days selection with CBR-2092 | rpoBH481YgyrAS84L, ΔK809parCS80F, A523D | 16 | 2 | >125 | 64 | 4 |
a
Step selections were undertaken in MHII broth medium with supplementation (CBR-2092) or without supplementation (ABT-719) with 0.002% (vol/vol) P-80.
b
Cipro, ciprofloxacin.
c
EtBr, ethidium bromide.
d
†, duplication.