TABLE 1.
Characteristics of strains used in this study
| Phenotypea and strain no. | Origin | SCCmec group | MIC (mg/liter)
|
|
|---|---|---|---|---|
| pH 7.4 | pH 5.5 | |||
| MSSA | ||||
| ATCC 25923 (β-lactamase −) | Laboratory standardb | NAg | 0.5 | 0.25 |
| ATCC 11632 (β-lactamase +) | Laboratory standardb | NA | 0.5-1 | 0.25-0.5 |
| NRS52 (VISA) | Clinical (bile infection)c | NA | 1 | 0.5 |
| Geometric mean | 0.72 | 0.36 | ||
| HA-MRSA | ||||
| ATCC 33591 (inducible) | Laboratory standardb | III | 2 | 0.5 |
| ATCC 33592 | Laboratory standardb | NDh | 2 | 0.5-1 |
| ATCC 43300 | Laboratory standardb | ND | 1 | 0.5 |
| N4120210 | Clinical (wound infection)d | I | 2 | 1 |
| N4112910 | Clinical (nasal swab)d | ND | 0.5-1 | 0.25-0.5 |
| N4120032 | Clinical (urinary tract infection)d | ND | 2 | 0.5 |
| NRS18 (VISA) | Clinical (wound, skin and soft tissue infection)-c | II | 0.5-1 | 0.5 |
| NRS126 (VISA) | Clinical (bloodstream infection)c | II | 1-2 | 0.25-0.5 |
| VRS1 (VRSA) | Clinical (catheter exit site)c | II | 2 | 0.5 |
| VRS2 (VRSA) | Clinical (wound infection)c | II | 1-2 | 0.5 |
| Geometric mean | 1.45 | 0.43 | ||
| CA-MRSA | ||||
| NRS192 (PVL +) | Clinical (pneumonia, septic arthritis)c | IVa | 2 | 1 |
| NRS384 (PVL +) | Clinical (wound, skin and soft tissue infection)c | IVa | 2 | 1 |
| N4090440 (PVL +) | Clinical (wound infection)d | IVa | 1 | 0.5 |
| N4042228 (PVL +) | Clinical (septicemia sec. to soft-tissues abscess)d | IVa | 1 | 0.5 |
| STA 44 (PVL +) | Clinicale | V | 2 | 1 |
| STA 268 (PVL +) | Clinicale | V | 2 | 1 |
| CHU (PVL +) | Clinicale | V | 2 | 1 |
| MEH2225605 (PVL +) | Clinicalf | IVa | 2 | 1 |
| NRS386 (PVL −) | Clinical (bloodstream infection)c | IVa | 2 | 0.5-1 |
| Geometric mean | 1.71 | 0.83 | ||
a
VISA, vancomycin intermediate S. aureus (MICs, >2 and <8 mg/liter); VRSA, vancomycin-resistant S. aureus (MICs, >8 mg/liter); PVL, Panton-Valentine leucocidin; −, negative; +, positive.
b
From the American Type Culture Collection.
c
From the Network on Antimicrobial Resistance in Staphylococcus aureus (operated by Eurofins Medinet, Inc., Herndon, VA).
d
Clinical collection (Y. Glupczynski, Cliniques Universitaires UCL de Mont-Godinne, Yvoir, Belgium).
e
Clinical collection (Y. C. Huang, Chang Gung Children's Hospital, Taiwan).
f
Clinical collection (L. Y. Hsu, Singapore General Hospital, Singapore).
g
NA, not applicable.
h
ND, not determined.