2JC7

The crystal structure of the carbapenemase OXA-24 reveals new insights into the mechanism of carbapenem-hydrolysis


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.5 Å
  • R-Value Free: 0.234 
  • R-Value Work: 0.192 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Crystal Structure of the Carbapenemase Oxa-24 Reveals Insights Into the Mechanism of Carbapenem Hydrolysis.

Santillana, E.Beceiro, A.Bou, G.Romero, A.

(2007) Proc.Natl.Acad.Sci.USA 104: 5354

  • DOI: 10.1073/pnas.0607557104
  • Also Cited By: 3G4P, 3FYZ, 3FV7

  • PubMed Abstract: 
  • Combating bacterial resistance to beta-lactams, the most widely used antibiotics, is an emergent and clinically important challenge. OXA-24 is a class D beta-lactamase isolated from a multiresistant epidemic clinical strain of Acinetobacter baumannii ...

    Combating bacterial resistance to beta-lactams, the most widely used antibiotics, is an emergent and clinically important challenge. OXA-24 is a class D beta-lactamase isolated from a multiresistant epidemic clinical strain of Acinetobacter baumannii. We have investigated how OXA-24 specifically hydrolyzes the last resort carbapenem antibiotic, and we have determined the crystal structure of OXA-24 at a resolution of 2.5 A. The structure shows that the carbapenem's substrate specificity is determined by a hydrophobic barrier that is established through the specific arrangement of the Tyr-112 and Met-223 side chains, which define a tunnel-like entrance to the active site. The importance of these residues was further confirmed by mutagenesis studies. Biochemical and microbiological analyses of specific point mutants selected on the basis of structural criteria significantly reduced the catalytic efficiency (k(cat)/K(m)) against carbapenems, whereas the specificity for oxacillin was noticeably increased. This is the previously unrecognized crystal structure that has been obtained for a class D carbapenemase enzyme. Accordingly, this information may help to improve the development of effective new drugs to combat beta-lactam resistance. More specifically, it may help to overcome carbapenem resistance in A. baumannii, probably one of the most worrying infectious threats in hospitals worldwide.


    Organizational Affiliation

    Departamento de Estructura y Función de Proteínas, Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Cientificas, Ramiro de Maeztu 9, E-28040 Madrid, Spain.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
BETA-LACTAMASE OXA-24
A
244Acinetobacter baumanniiMutation(s): 0 
Gene Names: blaOXA-33 (bla-OXA-40, blaOXA-24, blaOXA-40, oxa-24, oxa40)
Find proteins for Q8RLA6 (Acinetobacter baumannii)
Go to UniProtKB:  Q8RLA6
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
SO4
Query on SO4

Download SDF File 
Download CCD File 
A
SULFATE ION
O4 S
QAOWNCQODCNURD-UHFFFAOYSA-L
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.5 Å
  • R-Value Free: 0.234 
  • R-Value Work: 0.192 
  • Space Group: P 41 21 2
Unit Cell:
Length (Å)Angle (°)
a = 102.200α = 90.00
b = 102.200β = 90.00
c = 86.100γ = 90.00
Software Package:
Software NamePurpose
SCALAdata scaling
CNSrefinement
AMoREphasing
MOSFLMdata reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2007-03-20
    Type: Initial release
  • Version 1.1: 2011-05-08
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance