1HRC

HIGH-RESOLUTION THREE-DIMENSIONAL STRUCTURE OF HORSE HEART CYTOCHROME C


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.9 Å

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

High-resolution three-dimensional structure of horse heart cytochrome c.

Bushnell, G.W.Louie, G.V.Brayer, G.D.

(1990) J.Mol.Biol. 214: 585-595

  • DOI: 10.1016/0022-2836(90)90200-6

  • PubMed Abstract: 
  • The 1.94 A resolution three-dimensional structure of oxidized horse heart cytochrome c has been elucidated and refined to a final R-factor of 0.17. This has allowed for a detailed assessment of the structural features of this protein, including the p ...

    The 1.94 A resolution three-dimensional structure of oxidized horse heart cytochrome c has been elucidated and refined to a final R-factor of 0.17. This has allowed for a detailed assessment of the structural features of this protein, including the presence of secondary structure, hydrogen-bonding patterns and heme geometry. A comprehensive analysis of the structural differences between horse heart cytochrome c and those other eukaryotic cytochromes c for which high-resolution structures are available (yeast iso-1, tuna, rice) has also been completed. Significant conformational differences between these proteins occur in three regions and primarily involve residues 22 to 27, 41 to 43 and 56 to 57. The first of these variable regions is part of a surface beta-loop, whilst the latter two are located together adjacent to the heme group. This study also demonstrates that, in horse cytochrome c, the side-chain of Phe82 is positioned in a co-planar fashion next to the heme in a conformation comparable to that found in other cytochromes c. The positioning of this residue does not therefore appear to be oxidation-state-dependent. In total, five water molecules occupy conserved positions in the structures of horse heart, yeast iso-1, tuna and rice cytochromes c. Three of these are on the surface of the protein, serving to stabilize local polypeptide chain conformations. The remaining two are internally located. One of these mediates a charged interaction between the invariant residue Arg38 and a nearby heme propionate. The other is more centrally buried near the heme iron atom and is hydrogen bonded to the conserved residues Asn52, Tyr67 and Thr78. It is shown that this latter water molecule shifts in a consistent manner upon change in oxidation state if cytochrome c structures from various sources are compared. The conservation of this structural feature and its close proximity to the heme iron atom strongly implicate this internal water molecule as having a functional role in the mechanism of action of cytochrome c.


    Organizational Affiliation

    Department of Biochemistry, University of British Columbia, Vancouver, Canada.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
CYTOCHROME C
A
105Equus caballusGene Names: CYCS (CYC)
Find proteins for P00004 (Equus caballus)
Go to Gene View: CYCS
Go to UniProtKB:  P00004
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
HEM
Query on HEM

Download SDF File 
Download CCD File 
A
PROTOPORPHYRIN IX CONTAINING FE
HEME
C34 H32 Fe N4 O4
KABFMIBPWCXCRK-RGGAHWMASA-L
 Ligand Interaction
Modified Residues  1 Unique
IDChainsTypeFormula2D DiagramParent
ACE
Query on ACE
A
NON-POLYMERC2 H4 O

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Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.9 Å
  • Space Group: P 43
Unit Cell:
Length (Å)Angle (°)
a = 58.397α = 90.00
b = 58.397β = 90.00
c = 42.091γ = 90.00
Software Package:
Software NamePurpose
PROLSQrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

  • Deposited Date: 1994-08-16 
  • Released Date: 1994-11-01 
  • Deposition Author(s): Luo, Y., Brayer, G.D.

Revision History 

  • Version 1.0: 1994-11-01
    Type: Initial release
  • Version 1.1: 2008-03-24
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance