1I19

CRYSTAL STRUCTURE OF CHOLESTEROL OXIDASE FROM B.STEROLICUM


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.7 Å
  • R-Value Free: 0.201 
  • R-Value Work: 0.182 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Oxygen access to the active site of cholesterol oxidase through a narrow channel is gated by an Arg-Glu pair.

Coulombe, R.Yue, K.Q.Ghisla, S.Vrielink, A.

(2001) J.Biol.Chem. 276: 30435-30441

  • DOI: 10.1074/jbc.M104103200

  • PubMed Abstract: 
  • Cholesterol oxidase is a monomeric flavoenzyme that catalyzes the oxidation and isomerization of cholesterol to cholest-4-en-3-one. Two forms of the enzyme are known, one containing the cofactor non-covalently bound to the protein and one in which th ...

    Cholesterol oxidase is a monomeric flavoenzyme that catalyzes the oxidation and isomerization of cholesterol to cholest-4-en-3-one. Two forms of the enzyme are known, one containing the cofactor non-covalently bound to the protein and one in which the cofactor is covalently linked to a histidine residue. The x-ray structure of the enzyme from Brevibacterium sterolicum containing covalently bound FAD has been determined and refined to 1.7-A resolution. The active site consists of a cavity sealed off from the exterior of the protein. A model for the steroid substrate, cholesterol, can be positioned in the pocket revealing the structural factors that result in different substrate binding affinities between the two known forms of the enzyme. The structure suggests that Glu(475), located at the active site cavity, may act as the base for both the oxidation and the isomerization steps of the catalytic reaction. A water-filled channel extending toward the flavin moiety, inside the substrate-binding cavity, may act as the entry point for molecular oxygen for the oxidative half-reaction. An arginine and a glutamate residue at the active site, found in two conformations are proposed to control oxygen access to the cavity from the channel. These concerted side chain movements provide an explanation for the biphasic mode of reaction with dioxygen and the ping-pong kinetic mechanism exhibited by the enzyme.


    Related Citations: 
    • Crystallization and Preliminary X-Ray Analysis of Cholesterol Oxidase from Brevibacterium sterolicum Containing Covalently Bound FAD
      Croteau, N.,Vrielink, A.
      (1996) J.STRUCT.BIOL. 116: 317


    Organizational Affiliation

    Department of Biochemistry and Montréal Joint Center for Structural Biology, McIntyre Medical Sciences Building, McGill University, Montréal, Québec H3G 1Y6, Canada.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
CHOLESTEROL OXIDASE
A, B
561Brevibacterium sterolicumN/A
Find proteins for Q7SID9 (Brevibacterium sterolicum)
Go to UniProtKB:  Q7SID9
Small Molecules
Ligands 4 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
MN
Query on MN

Download SDF File 
Download CCD File 
B
MANGANESE (II) ION
Mn
WAEMQWOKJMHJLA-UHFFFAOYSA-N
 Ligand Interaction
FAD
Query on FAD

Download SDF File 
Download CCD File 
A, B
FLAVIN-ADENINE DINUCLEOTIDE
C27 H33 N9 O15 P2
VWWQXMAJTJZDQX-UYBVJOGSSA-N
 Ligand Interaction
EDO
Query on EDO

Download SDF File 
Download CCD File 
A, B
1,2-ETHANEDIOL
ETHYLENE GLYCOL
C2 H6 O2
LYCAIKOWRPUZTN-UHFFFAOYSA-N
 Ligand Interaction
CAC
Query on CAC

Download SDF File 
Download CCD File 
B
CACODYLATE ION
dimethylarsinate
C2 H6 As O2
OGGXGZAMXPVRFZ-UHFFFAOYSA-M
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.7 Å
  • R-Value Free: 0.201 
  • R-Value Work: 0.182 
  • Space Group: P 1 21 1
Unit Cell:
Length (Å)Angle (°)
a = 77.440α = 90.00
b = 124.470β = 109.17
c = 80.840γ = 90.00
Software Package:
Software NamePurpose
CNSrefinement
MLPHAREphasing
DENZOdata reduction
SCALEPACKdata scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2001-08-08
    Type: Initial release
  • Version 1.1: 2008-04-27
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Non-polymer description, Version format compliance