1VYD

Crystal structure of cytochrome C2 mutant G95E


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.3 Å
  • R-Value Free: 0.242 
  • R-Value Work: 0.198 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Protein Dynamics in the Region of the Sixth Ligand Methionine Revealed by Studies of Imidazole Binding to Rhodobacter Capsulatus Cytochrome C2 Hinge Mutants.

Dumortier, C.Fitch, J.Van Petegem, F.Vermeulen, W.Meyer, T.E.Van Beeumen, J.J.Cusanovich, M.A.

(2004) Biochemistry 43: 7717

  • DOI: 10.1021/bi0362370

  • PubMed Abstract: 
  • All class I c-type cytochromes studied to date undergo a dynamic process in the oxidized state, which results in the transient breaking of the iron-methionine-sulfur bond and sufficient movement to allow the binding of exogenous ligands (imidazole in ...

    All class I c-type cytochromes studied to date undergo a dynamic process in the oxidized state, which results in the transient breaking of the iron-methionine-sulfur bond and sufficient movement to allow the binding of exogenous ligands (imidazole in this work). In the case of Rhodobacter capsulatus cytochrome c(2), the sixth heme ligand Met96 and up to 14 flanking residues (positions 88-100, termed the hinge region), located between two relatively rigid helical regions, may be involved in structural changes leading to a transient high-spin species able to bind ligands. We have examined 14 mutations at 9 positions in the hinge region of Rhodobacter capsulatus cytochrome c(2) and have determined the structure of the G95E mutant. Mutations near the N- and C-terminus of the hinge region do not affect the kinetics of movement but allow us to further define that portion of the hinge that moves away from the heme to the 93-100 region in the amino acid sequence. Mutations at positions 93 and 95 can alter the rate constant for hinge movement (up to 20-fold), presumably as a result of altering the structure of the native cytochrome to favor a more open conformation. The structure of one of these mutants, G95E, suggests that interactions within the hinge region are stabilized while interaction between the hinge and the heme are destabilized. In contrast, mutations at positions 98 and 99 alter imidazole binding kinetics but not the hinge movement. Thus, it appears that these mutations affect the structure of the cytochrome after the hinge region has moved away from the heme, resulting in increased solvent access to the bound imidazole or alter interactions between the protein and the bound imidazole.


    Organizational Affiliation

    Department of Biochemistry and Molecular Biophysics, University of Arizona, Tucson, Arizona 85721, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
CYTOCHROME C2
A, B
116Rhodobacter capsulatus (strain ATCC BAA-309 / NBRC 16581 / SB1003)Mutation(s): 1 
Gene Names: cycA
Find proteins for P00094 (Rhodobacter capsulatus (strain ATCC BAA-309 / NBRC 16581 / SB1003))
Go to UniProtKB:  P00094
Small Molecules
Ligands 1 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
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.3 Å
  • R-Value Free: 0.242 
  • R-Value Work: 0.198 
  • Space Group: H 3 2
Unit Cell:
Length (Å)Angle (°)
a = 100.230α = 90.00
b = 100.230β = 90.00
c = 162.150γ = 120.00
Software Package:
Software NamePurpose
REFMACrefinement
SCALEPACKdata scaling
AMoREphasing
DENZOdata reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2004-06-17
    Type: Initial release
  • Version 1.1: 2012-06-20
    Type: Database references, Derived calculations, Non-polymer description, Other, Structure summary, Version format compliance
  • Version 1.2: 2018-06-13
    Type: Data collection, Structure summary