PDBsum entry 4jf6

Hydrolase

PDB id: 4jf6

Contents

Protein chain

239 a.a.

Ligands

PEG

Metals

__K

_CL ×4

Waters ×126

PDB id:

4jf6

Name:

Hydrolase

Title:

Structure of oxa-23 at ph 7.0

Structure:

Beta-lactamase. Chain: a. Synonym: beta-lactamase oxa-23, blaoxa-23, carbapenem-hydrolyzing beta-lactamase oxa-23, carbapenemase oxa-23, class d beta-lactamase oxa-23, class d beta-lactamase oxa-23, oxa-23, oxa-23 beta-lactamase, oxa-23 carbapenemase. Engineered: yes

Source:

Acinetobacter baumannii. Organism_taxid: 470. Gene: ari-1, bla(oxa-23), bla-oxa-23, bla-oxa-23, blaoxa-23, oxa-23, oxa-23, oxa23. Expressed in: escherichia coli. Expression_system_taxid: 562

Resolution:

2.50Å R-factor: 0.230 R-free: 0.285

Authors:

C.A.Smith,S.B.Vakulenko

Key ref:

C.A.Smith et al. (2013). Structural basis for carbapenemase activity of the OXA-23 β-lactamase from Acinetobacter baumannii. Chem Biol, 20, 1107-1115. PubMed id: 24012371 DOI: 10.1016/j.chembiol.2013.07.015

Date:

27-Feb-13 Release date: 25-Sep-13

Protein chain

Q9L4P2  (BLO23_ACIBA) -  Beta-lactamase OXA-23 from Acinetobacter baumannii

Seq: 273 a.a.

Struc: 239 a.a.*

* PDB and UniProt seqs differ at 1 residue position (black cross)

Enzyme reactions

• Enzyme class: E.C.3.5.2.6 - beta-lactamase.
• Pathway: Penicillin Biosynthesis and Metabolism
• Reaction: a beta-lactam + H2O = a substituted beta-amino acid
• Cofactor: Zn(2+)

DOI no: 10.1016/j.chembiol.2013.07.015

Chem Biol 20:1107-1115 (2013)

PubMed id: 24012371

Structural basis for carbapenemase activity of the OXA-23 β-lactamase from Acinetobacter baumannii.

C.A.Smith, N.T.Antunes, N.K.Stewart, M.Toth, M.Kumarasiri, M.Chang, S.Mobashery, S.B.Vakulenko.

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.