| Ambler (molecular) Class | Bush & Jacoby group (2009) | Substrate/target | Inhibition profile | Member examples | |
| Clavulanic acid | azobactam | ||||
| A | 2a | Penicillins | Yes | No | PC-1 |
| 2b | Penicillins, some of the 1st-generation cephalosporin | Yes | No | TEM-1, TEM-2, SHV-1 | |
| 2be | Extended spectrum cephalosporin, monobactam | Yes | No | TEM-3, SHV-2, CTX-M-15, PET-1, VEB-1 | |
| 2br | Penicillins | No | No | TEM-30, SHV-10 | |
| 2ber | Extended spectrum cephalosporin, monobactam | No | No | TEM-50 | |
| 2c | Carbenicillin | Yes | No | PSE-1, CARB-3 | |
| 2ce | Carbenicillin, cefepime | Yes | No | RTG-4 | |
| 2e | Extended spectrum beta-lactams | Yes | No | CepA | |
| B | 2f |
| Changing | No | KPC-2, 1M1-1, SME-1 |
| 3a | Carbapenems | No | Yes | IMP-1, VIM-1, CcrA, IND-1, NDM-1 | |
| C | 3b | Carbapenems | No | Yes | CphA, Sfh-1 |
| 1 | Cephalosporins | No | No | AmpC, P99, ACT 1, CMY-2, FOX-1, MIR-1 | |
| 1e | Cephalosporins | No | Yes | GC1, CMY-37 | |
| D | 2d | Cloxacillin | Changeable | No | OXA-1, OXA-10 |
| 2de | Extended spectrum cephalosporin | Changeable | No | OXA-11, OXA-15 | |
| 2df | Carbapenems | Variable | No | OXA-23, OXA-48 | |