1CI8

ESTERASE ESTB FROM BURKHOLDERIA GLADIOLI: AN ESTERASE WITH (BETA)-LACTAMASE FOLD.


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2 Å
  • R-Value Free: 0.247 
  • R-Value Work: 0.184 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

EstB from Burkholderia gladioli: a novel esterase with a beta-lactamase fold reveals steric factors to discriminate between esterolytic and beta-lactam cleaving activity

Wagner, U.G.Petersen, E.I.Schwab, H.Kratky, C.

(2002) Protein Sci. 11: 467-478

  • DOI: 10.1110/ps.33002
  • Primary Citation of Related Structures:  1CI9

  • PubMed Abstract: 
  • Esterases form a diverse class of enzymes of largely unknown physiological role. Because many drugs and pesticides carry ester functions, the hydrolysis of such compounds forms at least one potential biological function. Carboxylesterases catalyze th ...

    Esterases form a diverse class of enzymes of largely unknown physiological role. Because many drugs and pesticides carry ester functions, the hydrolysis of such compounds forms at least one potential biological function. Carboxylesterases catalyze the hydrolysis of short chain aliphatic and aromatic carboxylic ester compounds. Esterases, D-alanyl-D-alanine-peptidases (DD-peptidases) and beta-lactamases can be grouped into two distinct classes of hydrolases with different folds and topologically unrelated catalytic residues, the one class comprising of esterases, the other one of beta-lactamases and DD-peptidases. The chemical reactivities of esters and beta-lactams towards hydrolysis are quite similar, which raises the question of which factors prevent esterases from displaying beta-lactamase activity and vice versa. Here we describe the crystal structure of EstB, an esterase isolated from Burkholderia gladioli. It shows the protein to belong to a novel class of esterases with homology to Penicillin binding proteins, notably DD-peptidase and class C beta-lactamases. Site-directed mutagenesis and the crystal structure of the complex with diisopropyl-fluorophosphate suggest Ser75 within the "beta-lactamase" Ser-x-x-Lys motif to act as catalytic nucleophile. Despite its structural homology to beta-lactamases, EstB shows no beta-lactamase activity. Although the nature and arrangement of active-site residues is very similar between EstB and homologous beta-lactamases, there are considerable differences in the shape of the active site tunnel. Modeling studies suggest steric factors to account for the enzyme's selectivity for ester hydrolysis versus beta-lactam cleavage.


    Related Citations: 
    • Crystallization and Preliminary X-Ray Diffraction Studies of the Pseudomonas marginata Esterase ESTB
      Wagner, U.G.,Soelkner, B.,Petersen, E.I.,Schlacher, A.,Schwab, H.,Kratky, C.
      (1997) Acta Crystallogr.,Sect.D 53: 596


    Organizational Affiliation

    Institut für Chemie, Strukturbiologie, Karl-Franzens-Universität, A-8010 Graz, Austria. Wagner@Uni-Graz.at




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
PROTEIN (CARBOXYLESTERASE)
A, B
392Burkholderia gladioliGene Names: estB
EC: 3.1.1.-
Find proteins for Q9KX40 (Burkholderia gladioli)
Go to UniProtKB:  Q9KX40
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
IPA
Query on IPA

Download SDF File 
Download CCD File 
A, B
ISOPROPYL ALCOHOL
2-PROPANOL
C3 H8 O
KFZMGEQAYNKOFK-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2 Å
  • R-Value Free: 0.247 
  • R-Value Work: 0.184 
  • Space Group: P 32 2 1
Unit Cell:
Length (Å)Angle (°)
a = 82.922α = 90.00
b = 82.922β = 90.00
c = 193.460γ = 120.00
Software Package:
Software NamePurpose
XDSdata reduction
XSCALEdata scaling
MLPHAREphasing
X-PLORrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2001-12-12
    Type: Initial release
  • Version 1.1: 2008-04-26
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance
  • Version 1.3: 2017-10-04
    Type: Refinement description