TABLE 2.
Drug resistance of MRSA strains from Taiwan
| Drug, resistance gene | Presence of gene or gene mutation in the following MRSA strains (% of strains)a:
|
|||||
|---|---|---|---|---|---|---|
| PVL+ ST59 (n = 24) | PVL+ ST30 (n = 1) | PVL− ST239/ST900 (n = 8) | PVL− ST59 (n = 7) | PVL− ST5 (n = 1) | PVL− ST8 (n = 1) | |
| Tetracycline | ||||||
| tetK | + (75)b | − | + (63) | + (71)c | − | − |
| tetM | − | − | + | + (14) | − | − |
| Gentamicin-kanamycin, aac(6′)-aph(2″) | − | − | + | + (71) | + | − |
| Kanamycin | ||||||
| aph(3′)-IIIa | + (92)d | − | + | + (71) | − | − |
| ant(4′)-Ia | − | − | − | − | + | − |
| Streptomycin | ||||||
| aadE | + (92)d | − | + (25) | + (14) | − | − |
| spc | − | − | + | − | + | − |
| Erythromycin-clindamycin | ||||||
| ermA | − | − | + | − | + | + |
| ermB | + (92)d | − | − | + | − | − |
| ermC | − | − | − | + (14) | − | − |
| Erythromycin, msrA/msrB | − | − | − | − | − | − |
| Chloramphenicol, cat | + (75) | − | − | + (57) | − | − |
| Fluoroquinolonese | ||||||
| gyrA mutation | − | − | S84L (88), E88K (12) | − | S84L | − |
| grlA mutation | − | − | S80F | − | S80Y | − |
| Ampicillin, blaZ | + (96)b | + | + | + (86)c | +f | + |
| Cadmium | ||||||
| cadDX | + (96)b | + | + (63) | + (86)c | +f | − |
| cadA | − | − | + (50) | − | − | − |
| cadC | − | − | + (50) | − | − | − |
Strains are from Table 1. PVL+ ST59 includes groups 1 and groups 1-v1 to 1-v4. PVL+ ST30 corresponds to group 2. PVL− ST239/ST900 includes group 3 and group 3-v1. PVL− ST59 includes group 4 and groups 4-v1 to 4-v3. PVL− ST5 and PVL− ST8 correspond to groups 5 and 6, respectively.
The PCase plasmids of strains PM1 and PM9 code for tetracycline resistance (tetK), ampicillin resistance (blaZ), and cadmium resistance (cadDX).
The PCase plasmids of strains PM26 and PM34 code for tetracycline resistance (tetK), ampicillin resistance (blaZ), and cadmium resistance (cadDX).
The resistance to kanamycin, streptomycin, and erythromycin-clindamycin of strain PM1 was encoded by rgc (drug resistance gene cluster), shown in Fig. 1.
+, fluoroquinolone resistance with gyrA and grlA mutations; −, fluoroquinolone susceptible.
The PCase plasmid of strain PM29 codes only for ampicillin resistance (blaZ) and cadmium resistance (cadDX).