1EL4

STRUCTURE OF THE CALCIUM-REGULATED PHOTOPROTEIN OBELIN DETERMINED BY SULFUR SAS


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.73 Å
  • R-Value Free: 0.205 
  • R-Value Work: 0.188 
  • R-Value Observed: 0.191 

wwPDB Validation   3D Report Full Report


This is version 1.3 of the entry. See complete history


Literature

Structure of the Ca2+-regulated photoprotein obelin at 1.7 A resolution determined directly from its sulfur substructure.

Liu, Z.J.Vysotski, E.S.Chen, C.J.Rose, J.P.Lee, J.Wang, B.C.

(2000) Protein Sci 9: 2085-2093

  • DOI: https://doi.org/10.1110/ps.9.11.2085
  • Primary Citation of Related Structures:  
    1EL4

  • PubMed Abstract: 

    The crystal structure of the photoprotein obelin (22.2 kDa) from Obelia longissima has been determined and refined to 1.7 A resolution. Contrary to the prediction of a peroxide, the noncovalently bound substrate, coelenterazine, has only a single oxygen atom bound at the C2-position. The protein-coelenterazine 2-oxy complex observed in the crystals is photo-active because, in the presence of calcium ion, bioluminescence emission within the crystal is observed. This structure represents only the second de novo protein structure determined using the anomalous scattering signal of the sulfur substructure in the crystal. The method used here is theoretically different from that used for crambin in 1981 (4.72 kDa) and represents a significant advancement in protein crystal structure determination.


  • Organizational Affiliation

    Department of Biochemistry and Molecular Biology, University of Georgia, Athens 30602, USA.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
OBELIN195Obelia longissimaMutation(s): 0 
UniProt
Find proteins for Q27709 (Obelia longissima)
Explore Q27709 
Go to UniProtKB:  Q27709
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupQ27709
Sequence Annotations
Expand
  • Reference Sequence
Small Molecules
Ligands 2 Unique
IDChains Name / Formula / InChI Key2D Diagram3D Interactions
CTZ
Query on CTZ

Download Ideal Coordinates CCD File 
C [auth A]C2-HYDROXY-COELENTERAZINE
C26 H21 N3 O4
ULLMMKZQNNBLRN-SANMLTNESA-N
CL
Query on CL

Download Ideal Coordinates CCD File 
B [auth A]CHLORIDE ION
Cl
VEXZGXHMUGYJMC-UHFFFAOYSA-M
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.73 Å
  • R-Value Free: 0.205 
  • R-Value Work: 0.188 
  • R-Value Observed: 0.191 
  • Space Group: P 62
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 81.562α = 90
b = 81.562β = 90
c = 86.088γ = 120
Software Package:
Software NamePurpose
SOLVEphasing
CNSrefinement
HKL-2000data reduction
HKL-2000data scaling
ISASphasing

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2001-03-13
    Type: Initial release
  • Version 1.1: 2008-04-27
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance
  • Version 1.3: 2024-02-07
    Changes: Data collection, Database references, Derived calculations