1I54

CYTOCHROME C (TUNA) 2FE:1ZN MIXED-METAL PORPHYRINS


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.5 Å
  • R-Value Free: 0.247 
  • R-Value Work: 0.226 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Electron tunneling in protein crystals.

Tezcan, F.A.Crane, B.R.Winkler, J.R.Gray, H.B.

(2001) Proc.Natl.Acad.Sci.USA 98: 5002-5006

  • DOI: 10.1073/pnas.081072898
  • Primary Citation of Related Structures:  1I55

  • PubMed Abstract: 
  • The current understanding of electron tunneling through proteins has come from work on systems where donors and acceptors are held at fixed distances and orientations. The factors that control electron flow between proteins are less well understood, ...

    The current understanding of electron tunneling through proteins has come from work on systems where donors and acceptors are held at fixed distances and orientations. The factors that control electron flow between proteins are less well understood, owing to uncertainties in the relative orientations and structures of the reactants during the very short time that tunneling occurs. As we report here, the way around such structural ambiguity is to examine oxidation-reduction reactions in protein crystals. Accordingly, we have measured and analyzed the kinetics of electron transfer between native and Zn-substituted tuna cytochrome c (cyt c) molecules in crystals of known structure. Electron transfer rates [(320 s(-1) for *Zn-cyt c --> Fe(III)-cyt c; 2000 s(-1) for Fe(II)-cyt c --> Zn-cyt c(+))] over a Zn-Fe distance of 24.1 A closely match those for intraprotein electron tunneling over similar donor-acceptor separations. Our results indicate that van der Waals interactions and water-mediated hydrogen bonds are effective coupling elements for tunneling across a protein-protein interface.


    Organizational Affiliation

    Beckman Institute, MC 139-74, California Institute of Technology, Pasadena, CA 91125, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
CYTOCHROME C
A, B
103Thunnus alalungaGene Names: cyc
Find proteins for P81459 (Thunnus alalunga)
Go to UniProtKB:  P81459
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
HEM
Query on HEM

Download SDF File 
Download CCD File 
A, B
PROTOPORPHYRIN IX CONTAINING FE
HEME
C34 H32 Fe N4 O4
KABFMIBPWCXCRK-RGGAHWMASA-L
 Ligand Interaction
ZNH
Query on ZNH

Download SDF File 
Download CCD File 
A, B
PROTOPORPHYRIN IX CONTAINING ZN
C34 H32 N4 O4 Zn
FUTVBRXUIKZACV-UMRYFLQFDI
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.5 Å
  • R-Value Free: 0.247 
  • R-Value Work: 0.226 
  • Space Group: P 43
Unit Cell:
Length (Å)Angle (°)
a = 74.180α = 90.00
b = 74.180β = 90.00
c = 35.538γ = 90.00
Software Package:
Software NamePurpose
X-PLORmodel building
X-PLORphasing
DENZOdata reduction
SCALEPACKdata scaling
CNSrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2001-05-09
    Type: Initial release
  • Version 1.1: 2008-04-27
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance