1SF3

Structure of the reduced form of the P94A mutant of amicyanin


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.05 Å
  • R-Value Free: 0.147 
  • R-Value Work: 0.117 
  • R-Value Observed: 0.117 

Starting Model: experimental
View more details

wwPDB Validation   3D Report Full Report


This is version 1.4 of the entry. See complete history


Literature

Structural Studies of Two Mutants of Amicyanin from Paracoccus denitrificans That Stabilize the Reduced State of the Copper.

Carrell, C.J.Sun, D.Jiang, S.Davidson, V.L.Mathews, F.S.

(2004) Biochemistry 43: 9372-9380

  • DOI: https://doi.org/10.1021/bi049634z
  • Primary Citation of Related Structures:  
    1SF3, 1SF5, 1SFD, 1SFH

  • PubMed Abstract: 

    Mutation of Pro94 to phenylalanine or alanine significantly alters the redox properties of the type I copper center of amicyanin. Each mutation increases the redox midpoint potential (E(m)) value by at least 140 mV and shifts the pK(a) for the pH dependence of the E(m) value to a more acidic value. Atomic resolution (0.99-1.1 A) structures of both the P94F and P94A amicyanin have been determined in the oxidized and reduced states. In each amicyanin mutant, an electron-withdrawing hydrogen bond to the copper-coordinating thiolate sulfur of Cys92 is introduced by movement of the amide nitrogens of Phe94 and Ala94 much closer to the thiolate sulfur than in wild-type amicyanin. This is the likely explanation for the much more positive E(m) values which result from each of these mutations. The observed decrease in the pK(a) value for the pH dependence of the E(m) value that is seen in the mutants seems to be correlated with steric hindrance to the rotation of the His95 copper ligand which results from the mutations. In wild-type amicyanin the His95 side chain undergoes a redox and pH-dependent conformational change which accounts for the pH dependence of the E(m) value of amicyanin. The reduced P94A amicyanin exhibits two alternate conformations with the positions of the copper 1.4 A apart. In one of these conformations, a water molecule appears to have replaced Met98 as a copper ligand. The relevance of these structures to the electron transfer properties of P94F and P94A amicyanin are also discussed.


  • Organizational Affiliation

    Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, Missouri 63110, USA.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Amicyanin105Paracoccus denitrificansMutation(s): 1 
Gene Names: MAUCAMI
UniProt
Find proteins for P22364 (Paracoccus denitrificans)
Explore P22364 
Go to UniProtKB:  P22364
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP22364
Sequence Annotations
Expand
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.05 Å
  • R-Value Free: 0.147 
  • R-Value Work: 0.117 
  • R-Value Observed: 0.117 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 28.412α = 90
b = 55.557β = 95.98
c = 27.122γ = 90
Software Package:
Software NamePurpose
DENZOdata reduction
SCALEPACKdata scaling
CNSrefinement
SHELXL-97refinement
CNSphasing

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2004-07-27
    Type: Initial release
  • Version 1.1: 2008-04-29
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance
  • Version 1.3: 2021-10-27
    Changes: Database references, Derived calculations
  • Version 1.4: 2023-08-23
    Changes: Data collection, Refinement description