While several mechanisms of resistance to β-lactamase inhibitor combinations have been suggested in E. coli, production of inhibitor-resistant TEMs (IRTs) or OXA-1 enzymes has been reported to predominate as the mechanism conferring resistance to amoxicillin-clavulanic acid – a widely used antibiotic for the treatment of E. coli infections.
Besides the IRTs, an S130G inhibitor-resistant mutation associated with the SHV enzyme in the E. coli clinical isolate was reported by Prinarakis et al. as early as.