1I55

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


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.00 Å
  • R-Value Free: 0.247 
  • R-Value Work: 0.218 
  • R-Value Observed: 0.218 

wwPDB Validation   3D Report Full Report


This is version 2.1 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 U S A 98: 5002-5006

  • DOI: https://doi.org/10.1073/pnas.081072898
  • Primary Citation of Related Structures:  
    1I54, 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, 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:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
CYTOCHROME C
A, B
103Thunnus thynnusMutation(s): 0 
UniProt
Find proteins for P81459 (Thunnus alalunga)
Explore P81459 
Go to UniProtKB:  P81459
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP81459
Sequence Annotations
Expand
  • Reference Sequence
Small Molecules
Ligands 2 Unique
IDChains Name / Formula / InChI Key2D Diagram3D Interactions
ZNH
Query on ZNH

Download Ideal Coordinates CCD File 
D [auth A],
F [auth B]
PROTOPORPHYRIN IX CONTAINING ZN
C34 H32 N4 O4 Zn
FUTVBRXUIKZACV-RGGAHWMASA-L
HEC
Query on HEC

Download Ideal Coordinates CCD File 
C [auth A],
E [auth B]
HEME C
C34 H34 Fe N4 O4
HXQIYSLZKNYNMH-LJNAALQVSA-N
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.00 Å
  • R-Value Free: 0.247 
  • R-Value Work: 0.218 
  • R-Value Observed: 0.218 
  • Space Group: P 43
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 74.359α = 90
b = 74.359β = 90
c = 35.703γ = 90
Software Package:
Software NamePurpose
X-PLORmodel building
CNSrefinement
DENZOdata reduction
SCALEPACKdata scaling
X-PLORphasing

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2001-05-09
    Type: Initial release
  • Version 1.1: 2008-04-27
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance
  • Version 2.0: 2021-03-03
    Changes: Advisory, Atomic model, Data collection, Derived calculations, Non-polymer description, Structure summary
  • Version 2.1: 2023-08-09
    Changes: Data collection, Database references, Refinement description