1CHH

STRUCTURAL STUDIES OF THE ROLES OF RESIDUES 82 AND 85 AT THE INTERACTIVE FACE OF CYTOCHROME C


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.97 Å
  • R-Value Observed: 0.186 

wwPDB Validation   3D Report Full Report


This is version 2.0 of the entry. See complete history


Literature

Structural studies of the roles of residues 82 and 85 at the interactive face of cytochrome c.

Lo, T.P.Guillemette, J.G.Louie, G.V.Smith, M.Brayer, G.D.

(1995) Biochemistry 34: 163-171

  • DOI: https://doi.org/10.1021/bi00001a020
  • Primary Citation of Related Structures:  
    1CHH, 1CHI, 1CHJ

  • PubMed Abstract: 

    A combination of structural, functional, and mutagenic experiments has been used to study the roles of the invariant Phe82 and highly conserved Leu85 residues in cytochrome c, especially with respect to the complexation interface with electron transfer partners and maintenance of the hydrophobic heme pocket. Structural analyses show that the F82Y, L85A, and F82Y/L85A mutant proteins all retain the characteristic cytochrome c fold, but that conformational alterations are introduced in the direct vicinity of the mutation sites. In particular, the additional hydroxyl group of Tyr82 is in direct spatial conflict with the side chain of Leu85 in the F82Y mutant protein, leading to rotation of the side chain of Tyr82 out toward the protein surface. This strain is relieved in the F82Y/L85A mutant protein where the phenyl ring of Tyr82 is accommodated in a conformation comparable to that of the phenylalanine normally present at this location. In addition, the available space vacated by the replacement of Leu85 with an alanine allows for the inclusion of two new internal water molecules, one of which is bound to Tyr82 and the other to Arg13. In contrast, in the L85A mutant protein, no internal water molecules are observed in this exclusively hydrophobic pocket, which is partially filled by shifts in nearby side chains. Overall, the conformational changes observed result from the optimization of side chain packing to reflect the spatial requirements of new side chains, the minimization of both vacant internal space and the solvent exposure of hydrophobic groups, and the attainment of maximal hydrogen bonding between available polar groups.(ABSTRACT TRUNCATED AT 250 WORDS)


  • Organizational Affiliation

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


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
CYTOCHROME C108Saccharomyces cerevisiaeMutation(s): 0 
UniProt
Find proteins for P00044 (Saccharomyces cerevisiae (strain ATCC 204508 / S288c))
Explore P00044 
Go to UniProtKB:  P00044
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP00044
Sequence Annotations
Expand
  • Reference Sequence
Small Molecules
Ligands 2 Unique
IDChains Name / Formula / InChI Key2D Diagram3D Interactions
HEC
Query on HEC

Download Ideal Coordinates CCD File 
C [auth A]HEME C
C34 H34 Fe N4 O4
HXQIYSLZKNYNMH-LJNAALQVSA-N
SO4
Query on SO4

Download Ideal Coordinates CCD File 
B [auth A]SULFATE ION
O4 S
QAOWNCQODCNURD-UHFFFAOYSA-L
Modified Residues  1 Unique
IDChains TypeFormula2D DiagramParent
M3L
Query on M3L
A
L-PEPTIDE LINKINGC9 H21 N2 O2LYS
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.97 Å
  • R-Value Observed: 0.186 
  • Space Group: P 43 21 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 36.43α = 90
b = 36.43β = 90
c = 136.67γ = 90
Software Package:
Software NamePurpose
PROLSQrefinement

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 1994-12-20
    Type: Initial release
  • Version 1.1: 2008-03-21
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance
  • Version 1.3: 2017-11-29
    Changes: Derived calculations, Other
  • Version 2.0: 2021-03-03
    Changes: Atomic model, Data collection, Database references, Derived calculations, Non-polymer description, Structure summary