RNA-hydrolyzing activity of metallo-β-lactamase IMP-1

Structural and kinetic studies on metallo-β-lactamase IMP-1.

In an effort to probe for metal binding to metallo-β-lactamase (MβL) IMP-1, the enzyme was overexpressed, purified, and characterized. The resulting enzyme was shown to bind 2 equiv of Zn(II), exhibit significant catalytic activity, and yield EXAFS results similar to crystallographic data previously reported. Rapid kinetic studies showed that IMP-1 does not stabilize a nitrocefin-derived reacti...

Biochemical characterization of IMP-30, a metallo-β-lactamase with enhanced activity toward ceftazidime.

IMP-type enzymes constitute a clinically important family of metallo-β-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 in...

Emergence of Salmonella strain that produces IMP-1-type metallo-β-lactamase in a Japanese patient.

1Department of Joint Research Laboratory of Clinical Medicine and 2Department of Quality and Safety in Healthcare, Fujita Health University Hospital, Toyoake 470-1192; 3Department of Pediatrics, Fujita Health University School of Medicine, Toyoake 470-1192; 4Department of Bacteriology II, National Institute of Infectious Diseases, Tokyo 208-0011; and 5Department of Microbiology and Medical Zool...

The Development of an IMP Metallo-β-lactamase Detection Assay Using a Bioinformatic Approach

IMP-27, a Unique Metallo-β-Lactamase Identified in Geographically Distinct Isolates of Proteus mirabilis

A novel metallo-β-lactamase gene, blaIMP-27, was identified in unrelated Proteus mirabilis isolates from two geographically distinct locations in the United States. Both isolates harbor blaIMP-27 as part of the first gene cassette in a class 2 integron. Antimicrobial susceptibility testing indicated susceptibility to aztreonam, piperacillin-tazobactam, and ceftazidime but resistance to ertapene...