TABLE 1.
Restriction patterns of PCR products showing differentiation between the CTX-M clusters
| CTX-M clustera | No. of restriction sites
|
Expected length(s) (bp) of PstI-PvuII digestion product(s) | |
|---|---|---|---|
| PstI | PvuII | ||
| CTX-M-1 (CTX-M-1, -3, -10, -11, -12, -15 [UOE-1], -22) | 0 | 2 | 267, 156, 121 |
| CTX-M-2 (CTX-M-2, -4, -5, -6, -7, and -20; Toho-1; KluA) | 1 | 0 | 355, 188 |
| CTX-M-8 | 0 | 0 | 544 |
| CTX-M-9 | |||
| CTX-M-9, -13, and -16 | 1 | 1 | 426, 72, 46 |
| CTX-M-14 (-18, UOE-2, Toho-3), -15, -17, -19, and -21 | 0 | 1 | 472, 72 |
| Toho-2 | 0 | 1 | 466, 72 |
a
Grouping is based on >95% sequence identity of the coding genes.