Table 1. 3GC susceptibility phenotypes for ESBL-assigned alleles.
| Allele | Ceftazidime (R/n, %R) | Cefotaxime (R/n, %R) | Ceftriaxone (R/n, %R | Mutation/s |
| Exact matches to known alleles assigned here as ESBL | ||||
| SHV-2 | 3/6 (50%) | 1/2 (50%) | 3/3 (100%) | 238S |
| SHV-2A | 5/6 (83.3%) | 2/3 (66.7%) | 2/2 (100%) | 35Q, 238S |
| SHV-5 | 4/4 (100%) | 1/1 (100%) | 3/3 (100%) | 238S, 240K |
| SHV-7 | 8/8 (100%) | – | 8/8 (100%) | 238S, 240K |
| SHV-12 | 81/83 (97.6%) | 2/2 (100%) | 82/82 (100%) | 35Q, 238S, 240K |
| SHV-31.v1 | 2/2 (100%) | – | 2/2 (100%) | 35Q, 240K |
| SHV-106 | 0/1 (0%) | 0/1 (0%) | – | 238S |
| SHV-154 | 1/1 (100%) | – | 1/1 (100%) | 238S, 240K |
| Other alleles with omega-loop mutations | ||||
| SHV-1* +165R | 0/1 (0%) | 0/1 (0%) | – | 165R |
| SHV-103* +176E | 0/1 (0%) | – | 0/1 (0%) | 176E |
| SHV-178* +178 h | 0/6 (0%) | 0/6 (0%) | 0/1 (0%) | 35Q, 178 h |
| SHV-214* +175A | 0/2 (0%) | – | 0/2 (0%) | 175A |
| SHV-51 (175A) | 0/1 (0%) | 0/1 (0%) | – | 175A |
| Exact matches to alleles reported in the literature as ESBL but assigned here as WT | ||||
| SHV-27 | 14/304 (4.6%) | 4/106 (3.8%) | 12/211 (5.7%) | 156D |
| SHV-38 | 1/21 (4.8%) | 0/14 (0%) | 1/7 (14.3%) | 146V |
| SHV-40 | 3/31 (9.7%) | 0/15 (0%) | 3/30 (10%) | 35Q |
| SHV-41 | 0/17 (0%) | 0/9 (0%) | 1/8 (12.5%) | – |
| SHV-42 | 0/3 (0%) | 0/3 (0%) | – | 25S |
| SHV-65 | 1/6 (16.7%) | 1/3 (33.3%) | 0/4 (0%) | – |
| SHV-164 | 0/7 (0%) | 0/5 (0%) | 0/2 (0%) | – |
| SHV-187 | 3/135 (2.2%) | 0/87 (0%) | 4/51 (7.8%) | – |
Novel alleles identified in this study have been highlighted with an ‘*’.