1SG2

Crystal structure of the periplasmic chaperone Skp


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.35 Å
  • R-Value Free: 0.279 
  • R-Value Work: 0.223 
  • R-Value Observed: 0.226 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Structure of the periplasmic chaperone Skp suggests functional similarity with cytosolic chaperones despite differing architecture.

Korndorfer, I.P.Dommel, M.K.Skerra, A.

(2004) Nat Struct Mol Biol 11: 1015-1020

  • DOI: 10.1038/nsmb828
  • Primary Citation of Related Structures:  
    1SG2

  • PubMed Abstract: 
  • The 17-kDa protein (Skp) of Escherichia coli is a homotrimeric periplasmic chaperone for newly synthesized outer-membrane proteins. Here we present its X-ray structure at a resolution of 2.35 A. Three hairpin-shaped alpha-helical extensions reach out by approximately 60 A from a trimerization domain, which is composed of three intersubunit beta-sheets that wind around a central axis ...

    The 17-kDa protein (Skp) of Escherichia coli is a homotrimeric periplasmic chaperone for newly synthesized outer-membrane proteins. Here we present its X-ray structure at a resolution of 2.35 A. Three hairpin-shaped alpha-helical extensions reach out by approximately 60 A from a trimerization domain, which is composed of three intersubunit beta-sheets that wind around a central axis. The alpha-helical extensions approach each other at their distal turns, resulting in a fold that resembles a 'three-pronged grasping forceps'. The overall shape of Skp is reminiscent of the cytosolic chaperone prefoldin, although it is based on a radically different topology. The peculiar architecture, with apparent plasticity of the prongs and distinct electrostatic and hydrophobic surface properties, supports the recently proposed biochemical mechanism of this chaperone: formation of a Skp(3)-Omp complex protects the outer membrane protein from aggregation during passage through the bacterial periplasm.


    Related Citations: 
    • The periplasmic E. coli chaperone Skp is a trimer in solution: biophysical and preliminary crystallographic characterization
      Schlapschy, M., Dommel, M.K., Hadian, K., Fogarasi, M., Korndoerfer, I.P., Skerra, A.
      () To be published --: --

    Organizational Affiliation

    Lehrstuhl für Biologische Chemie, Technische Universität München, 85350 Freising-Weihenstephan, Germany.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Seventeen Kilodalton ProteinA, B, C153Escherichia coliMutation(s): 0 
Gene Names: hlpAskpompHb0178C0215Z0190ECS0180SF0168S0171
UniProt
Find proteins for P0AEU7 (Escherichia coli (strain K12))
Explore P0AEU7 
Go to UniProtKB:  P0AEU7
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP0AEU7
Protein Feature View
Expand
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.35 Å
  • R-Value Free: 0.279 
  • R-Value Work: 0.223 
  • R-Value Observed: 0.226 
  • Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 54.985α = 90
b = 83.911β = 90
c = 158.378γ = 90
Software Package:
Software NamePurpose
REFMACrefinement
MOSFLMdata reduction
CCP4data scaling
SHELXSphasing

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2004-09-14
    Type: Initial release
  • Version 1.1: 2008-04-29
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Advisory, Version format compliance