1QWD

CRYSTAL STRUCTURE OF A BACTERIAL LIPOCALIN, THE BLC GENE PRODUCT FROM E. COLI


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.75 Å
  • R-Value Free: 0.204 
  • R-Value Work: 0.169 
  • R-Value Observed: 0.171 

wwPDB Validation   3D Report Full Report


This is version 1.4 of the entry. See complete history


Literature

The crystal structure of the Escherichia coli lipocalin Blc suggests a possible role in phospholipid binding

Campanacci, V.Nurizzo, D.Spinelli, S.Valencia, C.Tegoni, M.Cambillau, C.

(2004) FEBS Lett 562: 183-188

  • DOI: https://doi.org/10.1016/S0014-5793(04)00199-1
  • Primary Citation of Related Structures:  
    1QWD

  • PubMed Abstract: 

    Lipocalins form a large multifunctional family of small proteins (15-25 kDa) first discovered in eukaryotes. More recently, several types of bacterial lipocalins have been reported, among which Blc from Escherichia coli is an outer membrane lipoprotein. As part of our structural genomics effort on proteins from E. coli, we have expressed, crystallized and solved the structure of Blc at 1.8 A resolution using remote SAD with xenon. The structure of Blc, the first of a bacterial lipocalin, exhibits a classical fold formed by a beta-barrel and a alpha-helix similar to that of the moth bilin binding protein. Its empty and open cavity, however, is too narrow to accommodate bilin, while the alkyl chains of two fatty acids or of a phospholipid could be readily modeled inside the cavity. Blc was reported to be expressed under stress conditions such as starvation or high osmolarity, during which the cell envelope suffers and requires maintenance. These data, together with our structural interpretation, suggest a role for Blc in storage or transport of lipids necessary for membrane repair or maintenance.


  • Organizational Affiliation

    Architecture et Fonction des Macromolécules Biologiques, UMR 6098, CNRS and Universités Aix-Marseille I and II, 31 chemin J. Aiguier, F-13402 Marseille Cedex 20, France.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Outer membrane lipoprotein blc
A, B
177Escherichia coliMutation(s): 0 
Gene Names: BLC OR B4149 OR Z5756 OR ECS5130
Membrane Entity: Yes 
UniProt
Find proteins for P0A901 (Escherichia coli (strain K12))
Explore P0A901 
Go to UniProtKB:  P0A901
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP0A901
Sequence Annotations
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.75 Å
  • R-Value Free: 0.204 
  • R-Value Work: 0.169 
  • R-Value Observed: 0.171 
  • Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 57.999α = 90
b = 80.779β = 90
c = 88.953γ = 90
Software Package:
Software NamePurpose
MOSFLMdata reduction
SCALAdata scaling
SHELXDphasing
SHARPphasing
REFMACrefinement
CCP4data scaling

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2004-04-06
    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: 2017-10-11
    Changes: Refinement description
  • Version 1.4: 2024-02-14
    Changes: Data collection, Database references