Table 3.
Mutations inactivating oprD in carbapenem-non-susceptible isolates.
| Type of mutation | Mutational characteristicsa | STs (no. of isolates) |
|---|---|---|
| Frameshift mutation | 1-bp deletion (G) at nt 276 | ST360 (19) |
| 1-bp deletion (T) at nt 912 | ST111 (22) | |
| 1-bp deletion (A) at nt 886 | ST385 (1) | |
| 1-bp deletion (G) at nt 376 | ST782 (1) | |
| 1-bp deletion (T) at nt 667 | ST385 (3) | |
| 2-bp deletion (AT) at nt 1114-1115 | ST316 (11), ST260 (4), ST2483 (4), ST485 (3), ST980 (2), ST274 (2), ST170 (1), ST270 (1), ST365 (1), ST499 (1), ST633 (1), ST782 (1), ST1028 (1), ST2420 (1), ST2492 (1), ST2493 (1), ST2494 (1) | |
| 2-bp deletion (TG) at nt 2-3 | ST2479 (1) | |
| 10-bp deletion at nt 126-143 (CGACCTGCTGCTCCGCAA) | ST385 (1) | |
| 10-bp deletion at nt 858-874 (TGCGCACACTTTCACCT) | ST292 (1) | |
| 5-bp insertion (ATGGC) at nt 1054-1055 | ST244 (4) | |
| 5-bp insertion (GGCCG) at nt 925-926 | ST244 (3), ST595 (1) | |
| 7-bp insertion (CCTGTTC) at nt 469-470 | ST244 (1) | |
| Premature stop codon | CAA→TAG at nt 199-201 | ST316 (4) |
| GAA→TAA at nt 220-222 | ST316 (3) | |
| TGG→TAG at nt 16-18 | ST639 (1) | |
| TGG→TGA at nt 1015-1017 | ST244 (2), ST385 (1) | |
| CAG→TAG at nt 496-498 | ST244 (1) | |
| IS insertion | IS1411 beginning at nt 788 | ST1158 (13) |
| IS1394 beginning at nt -11 | ST499 (4) | |
| IS1394 beginning at nt -1 | ST499 (1) | |
| Amino acid substitution | T103S, K115T, F170L | ST277 (3), ST2488 (2), ST2478 (1) |
| T103S, K115T, F170L, E185Q, P186G, V189T, R310E, A315G, G425A | ST245 (1), ST1648 (1) | |
| No mutation | None | ST244 (2), ST554 (3), ST111 (1) |
| Negative by PCR | Unknown change | ST1158 (2) |
IS, insertion sequence; nt, nucleotide. aSequences of oprD were compared to oprD in the reference strain PAO1. Bases in boldface indicate mutated nucleotides.