2SAS

STRUCTURE OF A SARCOPLASMIC CALCIUM-BINDING PROTEIN FROM AMPHIOXUS REFINED AT 2.4 ANGSTROMS RESOLUTION


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.40 Å
  • R-Value Work: 0.199 
  • R-Value Observed: 0.199 

wwPDB Validation   3D Report Full Report


This is version 1.4 of the entry. See complete history


Literature

Structure of a sarcoplasmic calcium-binding protein from amphioxus refined at 2.4 A resolution.

Cook, W.J.Jeffrey, L.C.Cox, J.A.Vijay-Kumar, S.

(1993) J Mol Biol 229: 461-471

  • DOI: https://doi.org/10.1006/jmbi.1993.1046
  • Primary Citation of Related Structures:  
    2SAS

  • PubMed Abstract: 

    The three-dimensional structure of a sarcoplasmic Ca(2+)-binding protein from the protochordate amphioxus has been determined at 2.4 A resolution using multiple-isomorphous-replacement techniques. The refined model includes all 185 residues, three calcium ions, and one water molecule. The final crystallographic R-factor is 0.199. Bond lengths and bond angles in the molecules have root-mean-square deviations from ideal values of 0.015 A and 2.8 degrees, respectively. The overall structure is highly compact and globular with a predominantly hydrophobic core, unlike the extended dumbbell-shaped structures of calmodulin or troponin C. There are four distinct domains with the typical helix-loop-helix Ca(2+)-binding motif (EF hand). The conformation of the pair of EF hands in the N-terminal half of the protein is unusual due to the presence of an aspartate residue in the twelfth position of the first Ca(2+)-binding loop, rather than the usual glutamate. The C-terminal half of the molecule contains one Ca(2+)-binding domain with a novel helix-loop-helix conformation and one Ca(2+)-binding domain that is no longer functional because of amino acid changes. The overall structure is quite similar to a sarcoplasmic Ca(2+)-binding protein from sandworm, although there is only about 12% amino acid sequence identity between them. The similarity of the structures of these two proteins suggests that all sarcoplasmic Ca(2+)-binding proteins will have the same general conformation, even though there is very little conservation of primary structure among the proteins from various species.


  • Organizational Affiliation

    Department of Pathology, University of Alabama, Birmingham 35294.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
SARCOPLASMIC CALCIUM-BINDING PROTEIN185Branchiostoma lanceolatumMutation(s): 0 
UniProt
Find proteins for P04570 (Branchiostoma lanceolatum)
Explore P04570 
Go to UniProtKB:  P04570
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP04570
Sequence Annotations
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.40 Å
  • R-Value Work: 0.199 
  • R-Value Observed: 0.199 
  • Space Group: C 2 2 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 59.6α = 90
b = 81.3β = 90
c = 82.4γ = 90
Software Package:
Software NamePurpose
X-PLORmodel building
PROLSQrefinement
X-PLORrefinement
X-PLORphasing

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 1993-10-31
    Type: Initial release
  • Version 1.1: 2008-03-03
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance
  • Version 1.3: 2019-07-17
    Changes: Data collection, Other, Refinement description
  • Version 1.4: 2019-08-14
    Changes: Data collection, Refinement description