Genetic and biochemical characterisation of CTX-M-37 extended-spectrum β-lactamase from an Enterobacter cloacae clinical isolate from Mongolia.

•An Enterobacter cloacae isolate with blaCTX-M-37 showed a relatively low cefotaxime MIC of 16mg/L.•The kcat/Km value of CTX-M-37 for cefotaxime was lower (2.0μM−1s−1) compared with CTX-M-3 (3.5μM−1s−1).•blaCTX-M-37 in E. cloacae was associated with an upstream ISEcp1 element with −35 and −10 putative promoter sequences.•The isolate had a truncated W sequence (37bp instead of 48bp).