title: Biochemical characteristics of New Delhi metallo-β-lactamase-1 show unexpected difference to other MBLs.
abstract: New Delhi metallo-β-lactamase (NDM-1) is a new metallo-β-lactamase (MBL) that has recently emerged as a global threat because it confers bacteria with resistance to almost all clinically used β-lactam antibiotics. To determine the molecular basis of this threat, NDM-1 was purified from Escherichia coli TransB (DE3) carrying cloned blaNDM-1 gene by an anion-exchange chromatography step followed by a gel permeation chromatography step. The purified enzyme was stable even in extremely alkaline buffer (pH 11) and reached its highest activity at a low temperature (15°C), which was different from other MBLs. The 50% inhibition concentration of EDTA against NDM-1 was 412 nM, which showed that NDM-1 was more susceptible to EDTA than other MBLs. The effects of zinc on NDM-1 differed between cephem and carbapenem complexes, but inhibition at high Zn(2+) concentration was observed for all of tested β-lactam compounds.
authors.affiliation: State Key Laboratory of Pathogens and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Fengtai District, Beijing, PR China.
authors.forename: Tao
authors.initials: T
authors.lastname: Li
authors.forename: Qin
authors.initials: Q
authors.lastname: Wang
authors.forename: Fanghong
authors.initials: F
authors.lastname: Chen
authors.forename: Xiang
authors.initials: X
authors.lastname: Li
authors.forename: Sen
authors.initials: S
authors.lastname: Luo
authors.forename: Huali
authors.initials: H
authors.lastname: Fang
authors.forename: Dehui
authors.initials: D
authors.lastname: Wang
authors.forename: Zhan
authors.initials: Z
authors.lastname: Li
authors.forename: Xiaojun
authors.initials: X
authors.lastname: Hou
authors.forename: Hui
authors.initials: H
authors.lastname: Wang
mesh_terms: D055162:Biocatalysis / Q000187:drug effects; D004492:Edetic Acid / Q000494:pharmacology; D004591:Electrophoresis, Polyacrylamide Gel; D004795:Enzyme Stability / Q000187:drug effects; D004926:Escherichia coli / Q000187:drug effects / Q000201:enzymology*; D006801:Humans; D006863:Hydrogen-Ion Concentration / Q000187:drug effects; D006868:Hydrolysis / Q000187:drug effects; D020128:Inhibitory Concentration 50; D007700:Kinetics; D013379:Substrate Specificity / Q000187:drug effects; D013696:Temperature; D015032:Zinc / Q000494:pharmacology; D001618:beta-Lactamases / Q000302:isolation & purification / Q000378:metabolism*; D047090:beta-Lactams / Q000494:pharmacology
chemical_list: D047090:beta-Lactams; D004492:Edetic Acid; D001618:beta-Lactamases; C552864:beta-lactamase NDM-1; D015032:Zinc