1BC2

ZN-DEPENDENT METALLO-BETA-LACTAMASE FROM BACILLUS CEREUS


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.90 Å
  • R-Value Free: 0.279 
  • R-Value Work: 0.208 
  • R-Value Observed: 0.208 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Crystal structure of the zinc-dependent beta-lactamase from Bacillus cereus at 1.9 A resolution: binuclear active site with features of a mononuclear enzyme.

Fabiane, S.M.Sohi, M.K.Wan, T.Payne, D.J.Bateson, J.H.Mitchell, T.Sutton, B.J.

(1998) Biochemistry 37: 12404-12411

  • DOI: 10.1021/bi980506i
  • Primary Citation of Related Structures:  
    1BC2

  • PubMed Abstract: 
  • The structure of the zinc-dependent beta-lactamase II from Bacillus cereus has been determined at 1.9 A resolution in a crystal form with two molecules in the asymmetric unit and 400 waters (space group P3121; Rcryst = 20.8%). The active site contains two zinc ions: Zn1 is tightly coordinated by His86, His88, and His149, while Zn2 is loosely coordinated by Asp90, Cys168, and His210 ...

    The structure of the zinc-dependent beta-lactamase II from Bacillus cereus has been determined at 1.9 A resolution in a crystal form with two molecules in the asymmetric unit and 400 waters (space group P3121; Rcryst = 20.8%). The active site contains two zinc ions: Zn1 is tightly coordinated by His86, His88, and His149, while Zn2 is loosely coordinated by Asp90, Cys168, and His210. A water molecule (W1) lies between the two zinc ions but is significantly closer to Zn1 and at a distance of only 1.9 A is effectively a hydroxide moiety and a potential, preactivated nucleophile. In fact, Asp90 bridges W1 to Zn2, and its location is thus distinct from that of the bridging water molecules in the binuclear zinc peptidases or other binuclear zinc hydrolases. Modeling of penicillin, cephalosporin, and carbapenem binding shows that all are readily accommodated within the shallow active site cleft of the enzyme, and the Zn1-bound hydroxide is ideally located for nucleophilic attack at the beta-lactam carbonyl. This enzyme also functions with only one zinc ion present. The Zn1-Zn2 distances differ in the two independent molecules in the crystal (3.9 and 4.4 A), yet the Zn1-W1 distances are both 1.9 A, arguing against involvement of Zn2 in W1 activation. The role of Zn2 is unclear, but the B. cereus enzyme may be an evolutionary intermediate between the mono- and bizinc metallo-beta-lactamases. The broad specificity of this enzyme, together with the increasing prevalence of zinc-dependent metallo-beta-lactamases, poses a real clinical threat, and this structure provides a basis for understanding its mechanism and designing inhibitors.


    Organizational Affiliation

    The Randall Institute, King's College London, U.K.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
METALLO-BETA-LACTAMASE IIA, B227Bacillus cereusMutation(s): 0 
Gene Names: blm
EC: 3.5.2.6
UniProt
Find proteins for P04190 (Bacillus cereus)
Explore P04190 
Go to UniProtKB:  P04190
Protein Feature View
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.90 Å
  • R-Value Free: 0.279 
  • R-Value Work: 0.208 
  • R-Value Observed: 0.208 
  • Space Group: P 31 2 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 67.63α = 90
b = 67.63β = 90
c = 178.38γ = 120
Software Package:
Software NamePurpose
SOLOMONphasing
X-PLORmodel building
X-PLORrefinement
DENZOdata reduction
CCP4data scaling
SCALAdata scaling
TRUNCATE)data scaling
X-PLORphasing

Structure Validation

View Full Validation Report




Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 1998-10-14
    Type: Initial release
  • Version 1.1: 2008-03-03
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance