TABLE 3.
Characterization of β-lactamase genes in E. coli clinical isolatesa
| E. coli isolate | PFGE type | pI | Detection of bla genes by PCR
|
|
|---|---|---|---|---|
| blaCTX-M | Additional broad and extended bla genes | |||
| 1020 | A | 5.4; 7.9 | CTX-M-2 | TEM-1; OXA-2 |
| 1438 | A | 5.4; 7.9 | CTX-M-2 | TEM-1 |
| 1241 | A | 5.4; 6.5; 7.6; 7.9 | CTX-M-2 | TEM-1 |
| 1254 | A | 5.4; 7.9 | CTX-M-2 | TEM-1; OXA-2 |
| 1131 | A | 5.4; 7.6; 7.8; 7.9 | CTX-M-2 | TEM-1 |
| 1482 | A | 5.4; 7.6; 7.9 | CTX-M-2 | TEM-1 |
| 1027 | B | 5.4; 7.7; 7.9 | CTX-M-2 | TEM-1; OXA-2 |
| 1031 | C | 5.4; 6.5; 7 7.5; 7.9 | CTX-M-2 | TEM-33 |
| 1227 | C | 5.4; 7.9 | CTX-M-2 | TEM-1; OXA-2 |
| 1266 | D | 5.4; 7.8; 8.2 | NI | SHV-12 |
| 1292 | D | 5.4; 5.6; 7.7; 7.9; 8.2 | CTX-M-2 | TEM-1; SHV-12; OXA-2 |
| 1204 | E | 5.2; 7.7; 7.9 | CTX-M-2 | TEM-30, OXA-2 |
| 1393 | F | 5.4; 6.8; 7.0 | CTX-M-39 | TEM-1 |
| 1430 | G | 5.4; 6.0; 6.8; 7.0 | CTX-M-39 | TEM-1 |
| 1455 | H | 5.4; 8.2 | NI | TEM-1, SHV-5 |
| 1299 | I | 5.4; 7.7; 7.9 | CTX-M-2 | TEM-1, OXA-2 |
| 1313 | I | 5.4; 6.5; 7.9 | CTX-M-2 | TEM-1, OXA-2 |
| 1466 | J | 5.4; 6.0; 6.8; 7.0 | CTX-M-2b; CTX-M-39 | TEM-1 |
| 1326 | K | 5.4; 7.8; 7.9 | CTX-M-2 | TEM-1 |
| 1356 | K | 5.4; 7.9 | CTX-M-2 | TEM-1 |
a
ESBL genes and the pI of CTX-M-2, 7.9, are marked in bold letters; CTX-M-39 and the proposed pI 6.8 to 7.0 are underlined. NI, not identified by PCR, but hybridized with CTX-M-2 probe in the Southern analysis.
b
blaCTX-M-2 gene detected in this strain by PCR, but a beta-lactamase with pI of 7.9 was not observed.