title: Structural and mechanistic insights into NDM-1 catalyzed hydrolysis of cephalosporins.
abstract: Cephalosporins constitute a large class of β-lactam antibiotics clinically used as antimicrobial drugs. New Dehli metallo-β-lactamase (NDM-1) poses a global threat to human health as it confers on bacterial pathogen resistance to almost all β-lactams, including penicillins, cephalosporins, and carbapenems. Here we report the first crystal structures of NDM-1 in complex with cefuroxime and cephalexin, as well as NMR spectra monitoring cefuroxime and cefixime hydrolysis catalyzed by NDM-1. Surprisingly, cephalosporoate intermediates were captured in both crystal structures determined at 1.3 and 2.0 Å. These results provide detailed information concerning the mechanism and pathways of cephalosporin hydrolysis. We also present the crystal structure and enzyme assays of a D124N mutant, which reveals that D124 most likely plays a more structural than catalytic role.
authors.affiliation: National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences , Beijing 100101, China.
authors.forename: Han
authors.initials: H
authors.lastname: Feng
authors.forename: Jingjin
authors.initials: J
authors.lastname: Ding
authors.forename: Deyu
authors.initials: D
authors.lastname: Zhu
authors.forename: Xuehui
authors.initials: X
authors.lastname: Liu
authors.forename: Xueyong
authors.initials: X
authors.lastname: Xu
authors.forename: Ying
authors.initials: Y
authors.lastname: Zhang
authors.forename: Shanshan
authors.initials: S
authors.lastname: Zang
authors.forename: Da-Cheng
authors.initials: DC
authors.lastname: Wang
authors.forename: Wei
authors.initials: W
authors.lastname: Liu
mesh_terms: D055162:Biocatalysis; D002511:Cephalosporins / Q000737:chemistry* / Q000378:metabolism; D018360:Crystallography, X-Ray; D006868:Hydrolysis; D008958:Models, Molecular; D011487:Protein Conformation; D001618:beta-Lactamases / Q000737:chemistry / Q000378:metabolism*
chemical_list: D002511:Cephalosporins; D001618:beta-Lactamases; C552864:beta-lactamase NDM-1