Biochemical Characterization of IMP-30, a Metallo-β-Lactamase with Enhanced Activity toward Ceftazidime

IMP-type enzymes constitute a clinically important family of metallo-beta-lactamases that has grown dramatically in the past decade to its current 45 known members. Here, we report the biochemical characterization of IMP-30 in comparison to IMP-1, from which it deviates by a single E59K mutation. Kinetics, MIC assays, docking, and molecular dynamics simulations support a scenario in which Lys59 interacts with the ceftazidime R-1 group, resulting in increased water access and enhanced turnover and MIC of ceftazidime.