1L4I

Crystal Structure of the Periplasmic Chaperone SfaE


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.2 Å
  • R-Value Free: 0.244 
  • R-Value Work: 0.190 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Structure of the S pilus periplasmic chaperone SfaE at 2.2 A resolution.

Knight, S.D.Choudhury, D.Hultgren, S.Pinkner, J.Stojanoff, V.Thompson, A.

(2002) Acta Crystallogr.,Sect.D 58: 1016-1022


  • PubMed Abstract: 
  • S pili are sialic acid binding hair-like appendages expressed by pathogenic strains of Escherichia coli. The presence of S pili has been implicated as a virulence factor in both urinary-tract infections and new-born meningitis. Assembly of S pili pro ...

    S pili are sialic acid binding hair-like appendages expressed by pathogenic strains of Escherichia coli. The presence of S pili has been implicated as a virulence factor in both urinary-tract infections and new-born meningitis. Assembly of S pili proceeds via the ubiquitous chaperone/usher pathway. Previously, structures of the homologous chaperones PapD and FimC involved in assembly of P and type-1 pili, respectively, have been solved. Here, the 2.2 A X-ray structure of the S pilus chaperone SfaE is reported. SfaE has the same overall L-shaped structure as PapD and FimC, with two immunoglobulin-like domains oriented at about a 90 degrees angle to each other. Conserved residues in the subunit-binding cleft known to be critical for chaperone function occupy essentially identical positions in SfaE, FimC and PapD. As in free PapD and FimC, the long F1-G1 loop connecting the two last strands of the N-terminal domain is disordered. SfaE crystallizes as a dimer with an extensive dimer interface involving the subunit-binding surfaces of the chaperone. Dimerization via these regions has previously been observed for PapD and might be a general side effect arising from the subunit-binding properties of periplasmic chaperones. The domain interface contains an extended hydrogen-bond network involving three invariant charged residues and two structurally conserved water molecules. It is suggested that disruption of the domain interactions may destabilize the N-terminal domain through exposure of three conserved hydrophobic residues, thereby promoting release of pilus subunits during pilus assembly.


    Organizational Affiliation

    Department of Molecular Biology, Uppsala Biomedical Centre, Swedish University of Agricultural Sciences, Box 590, S-753 24 Uppsala, Sweden. stefan@xray.bmc.uu.se




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
SfaE PROTEIN
A, B
206Escherichia coliGene Names: focC
Find proteins for P62609 (Escherichia coli)
Go to UniProtKB:  P62609
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.2 Å
  • R-Value Free: 0.244 
  • R-Value Work: 0.190 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 53.500α = 90.00
b = 84.240β = 90.00
c = 97.340γ = 90.00
Software Package:
Software NamePurpose
SCALEPACKdata scaling
SHARPphasing
REFMACrefinement
DENZOdata reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2002-06-12
    Type: Initial release
  • Version 1.1: 2008-04-28
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance