Table 2.
Resistance phenotype of class 1 integrons and their gene cassettes in76 intl1-positive Proteus mirabilis isolates.
| Integrons group (no. of isolates) | Amplicon size of integrons (Kb) | Gene cassette(s) | Resistance phenotype | ERIC type (number) |
|---|---|---|---|---|
| A single amplicon produced | ||||
| 1 (1) | 3.5 | aadB-cat-oxa10-aadA1 | KmCAmSmSp | G (1) |
| 2 (1) | 3.2 | aac(6’)-Ib-aacA7-cmlA | GmCTpSmSp | H (1) |
| 3 (38) | 2.1 | dfr12-orfF-aadA2 | TpSmSp | C (9), D (4), E (2), G(21), H (1), ND(1) |
| 4 (8) | 1.8 | aadB-aadA2 | GmSmSp | B (2), G (4), ND (2) |
| 5 (5) | 1.8 | dfrA1-aadA1a | TpSmSp | A (1), B (1), G (3) |
| 6 (3) | 1.0 | aadA1 | SmSp | E (1), G (2) |
| 7 (5) | 0.9 | dfr12 | Tp | C (2), D (1), ND(2) |
| Two or more amplicons produced | ||||
| 8 (5) | 2.1/0.9 | dfr12-orfF-aadA2/dfr12 | TpSmSp | C (2), D (2), G (1) |
| 9 (3) | 2.1/1.8 | dfr12-orfF-aadA2/aadB-aadA2 | TpSmSp | C (1), F (1), G(1) |
| 10 (2) | 2.1/1.8/0.9 | dfr12-orfF-aadA2/aadB-aadA2/ dfr12 | TpSmSpGm | C (1), G (1) |
| 11 (1) | 3.1/2.1/1.8 | aadB-cat-aadA1a/dfr12-orfF-aadA2/dfrA1- aadA1a | KmTpSmSp | G (1) |
| Negative for cassette regions | ||||
| 12 (4) | 0.15 | – | – | C (1), D (2), ND(1) |
ND, not detected.
Am, ampicillin; C, chloramphenicol; Gm, gentamicin; Km, kenamycin; Tp, trimethoprim; Sm, streptomycin; Sp, spectinomycin.