3EKD

Crystal structure of the A264M heme domain of cytochrome P450 BM3


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.50 Å
  • R-Value Free: 0.252 
  • R-Value Work: 0.217 
  • R-Value Observed: 0.219 

wwPDB Validation   3D Report Full Report


This is version 1.1 of the entry. See complete history


Literature

Novel haem co-ordination variants of flavocytochrome P450BM3.

Girvan, H.M.Toogood, H.S.Littleford, R.E.Seward, H.E.Smith, W.E.Ekanem, I.S.Leys, D.Cheesman, M.R.Munro, A.W.

(2009) Biochem J 417: 65-76

  • DOI: 10.1042/BJ20081133
  • Primary Citation of Related Structures:  
    3EKB, 3EKD, 3EKF

  • PubMed Abstract: 
  • Bacillus megaterium flavocytochrome P450 BM3 is a catalytically self-sufficient fatty acid hydroxylase formed by fusion of soluble NADPH-cytochrome P450 reductase and P450 domains. Selected mutations at residue 264 in the haem (P450) domain of the enzyme lead to novel amino acid sixth (distal) co-ordination ligands to the haem iron ...

    Bacillus megaterium flavocytochrome P450 BM3 is a catalytically self-sufficient fatty acid hydroxylase formed by fusion of soluble NADPH-cytochrome P450 reductase and P450 domains. Selected mutations at residue 264 in the haem (P450) domain of the enzyme lead to novel amino acid sixth (distal) co-ordination ligands to the haem iron. The catalytic, spectroscopic and thermodynamic properties of the A264M, A264Q and A264C variants were determined in both the intact flavocytochromes and haem domains of P450 BM3. Crystal structures of the mutant haem domains demonstrate axial ligation of P450 haem iron by methionine and glutamine ligands trans to the cysteine thiolate, creating novel haem iron ligand sets in the A264M/Q variants. In contrast, the crystal structure of the A264C variant reveals no direct interaction between the introduced cysteine side chain and the haem, although EPR data indicate Cys(264) interactions with haem iron in solution. The A264M haem potential is elevated by comparison with wild-type haem domain, and substrate binding to the A264Q haem domain results in a approximately 360 mV increase in potential. All mutant haem domains occupy the conformation adopted by the substrate-bound form of wild-type BM3, despite the absence of added substrate. The A264M mutant (which has higher dodecanoate affinity than wild-type BM3) co-purifies with a structurally resolved lipid. These data demonstrate that a single mutation at Ala(264) is enough to perturb the conformational equilibrium between substrate-free and substrate-bound P450 BM3, and provide firm structural and spectroscopic data for novel haem iron ligand sets unprecedented in nature.


    Organizational Affiliation

    Manchester Interdisciplinary Biocentre, University of Manchester, Faculty of Life Sciences, 131 Princess Street, Manchester M17DN, UK.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Cytochrome P450(BM-3)A, B470Priestia megateriumMutation(s): 1 
Gene Names: cyp102A1cyp102
EC: 1.14.14.1 (PDB Primary Data), 1.6.2.4 (UniProt)
UniProt
Find proteins for P14779 (Bacillus megaterium (strain ATCC 14581 / DSM 32 / JCM 2506 / NBRC 15308 / NCIMB 9376 / NCTC 10342 / NRRL B-14308 / VKM B-512))
Explore P14779 
Go to UniProtKB:  P14779
Protein Feature View
Expand
  • Reference Sequence
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
HEM
Query on HEM

Download Ideal Coordinates CCD File 
D [auth A], E [auth B]PROTOPORPHYRIN IX CONTAINING FE
C34 H32 Fe N4 O4
KABFMIBPWCXCRK-RGGAHWMASA-L
 Ligand Interaction
PAM
Query on PAM

Download Ideal Coordinates CCD File 
C [auth A]PALMITOLEIC ACID
C16 H30 O2
SECPZKHBENQXJG-FPLPWBNLSA-N
 Ligand Interaction
External Ligand Annotations 
IDBinding Affinity (Sequence Identity %)
PAMKd:  7400   nM  Binding MOAD
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.50 Å
  • R-Value Free: 0.252 
  • R-Value Work: 0.217 
  • R-Value Observed: 0.219 
  • Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 63.769α = 90
b = 125.171β = 90
c = 153.943γ = 90
Software Package:
Software NamePurpose
ADSCdata collection
REFMACrefinement
MOSFLMdata reduction
SCALAdata scaling

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2008-12-30
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Version format compliance