TABLE 1.
Susceptibilities of strains to selected Fqs and mutations in the parC, parE, gyrA, and gyrB genesa
| Strain | MIC (μg/ml)
|
Amino acid change (codon change)b
|
|||||||
|---|---|---|---|---|---|---|---|---|---|
| Cp
|
SPA
|
CLX, agar dilution | |||||||
| E test | Agar dilution | E test | Agar dilution | ParCc | ParE | GyrAd | GyrB | ||
| S. pneumoniae R6 | 0.5 | 0.5 | 0.25 | 0.25 | 0.125 | — | — | — | — |
| S. oralis NCTC11427 | 4 | 2 | 0.5 | 0.5 | 0.125 | — | — | — | ND |
| S. oralis ATCC10557 | 2 | 2 | 0.5 | 0.5 | 0.125 | — | — | — | ND |
| S. mitis NCTC12261 | 1 | 1 | 0.25 | 0.25 | 0.06 | — | — | ND | — |
| S. mitis V1e | 16 | 4 | 1 | 0.25 | 0.125 | — | — | ND | ND |
| S. mitis V2 | 16 | 4 | 1 | 0.5 | 0.125 | — | — | ND | ND |
| S. mitis V3 | 16 | 4 | 1 | 0.25 | 0.125 | — | — | ND | ND |
| S. mitis V4 | 16 | 4 | 1 | 0.5 | 0.125 | — | — | ND | ND |
| S. sanguis V5 | 16 | 4 | 1 | 0.5 | 0.125 | — | — | ND | 425A→G (GCT→GGT) |
| S. mitis V6 | 16 | 4 | 2 | 0.5 | 0.125 | — | — | — | 425A→G (GCT→GGT) |
| S. mitis V10 | 16 | 4 | 1 | 0.5 | 0.125 | 79S→F (TCT→TTT) | — | — | ND |
| S. mitis V8 | >32 | 16 | 2 | 1 | 0.25 | 79S→F (TCT→TTT) | — | — | — |
| S. oralis V9 | >32 | 32 | 2 | 1 | 0.5 | 79S→Y (TCT→TAT) | — | — | — |
a
SPA, sparfloxacin; CLX, clinafloxacin; ND, not determined.
b
Positions of substitutions are according to the coordinates for S. pneumoniae R6. —, no change.
c
The sequenced strains had an additional 91N→D (AAC→GAC) change compared to the sequence of S. pneumoniae R6.
d
The sequenced strains had an additional 114S→G (AGT→GGT) change compared to the sequence of S. pneumoniae R6.
e
Classification of the VGS clinical isolates to the species level was done with the API 20-Strep and ID 32-Strep systems.