PDBsum entry 4jf6

Hydrolase

PDB id: 4jf6

Contents

Protein chain

239 a.a.

Ligands

PEG

Metals

__K

_CL ×4

Waters ×126

References listed in PDB file

Key reference

• Title: Structural basis for carbapenemase activity of the oxa-23 β-Lactamase from acinetobacter baumannii.
• Authors: C.A.Smith, N.T.Antunes, N.K.Stewart, M.Toth, M.Kumarasiri, M.Chang, S.Mobashery, S.B.Vakulenko.
• Ref.: Chem Biol, 2013, 20, 1107-1115. [DOI no: 10.1016/j.chembiol.2013.07.015]
• PubMed id: 24012371

Abstract

Dissemination of Acinetobacter baumannii strains harboring class D β-lactamases producing resistance to carbapenem antibiotics severely limits our ability to treat deadly Acinetobacter infections. Susceptibility determination in the A. baumannii background and kinetic studies with a homogeneous preparation of OXA-23 β-lactamase, the major carbapenemase present in A. baumannii, document the ability of this enzyme to manifest resistance to last-resort carbapenem antibiotics. We also report three X-ray structures of OXA-23: apo OXA-23 at two different pH values, and wild-type OXA-23 in complex with meropenem, a carbapenem substrate. The structures and dynamics simulations reveal an important role for Leu166, whose motion regulates the access of a hydrolytic water molecule to the acyl-enzyme species in imparting carbapenemase activity.