4K8W

An arm-swapped dimer of the S. pyogenes pilin specific assembly factor SipA


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.67 Å
  • R-Value Free: 0.215 
  • R-Value Work: 0.185 
  • R-Value Observed: 0.187 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history


Literature

An arm-swapped dimer of the Streptococcus pyogenes pilin specific assembly factor SipA.

Young, P.G.Kang, H.J.Baker, E.N.

(2013) J Struct Biol 183: 99-104

  • DOI: 10.1016/j.jsb.2013.05.021
  • Primary Citation of Related Structures:  
    4K8W

  • PubMed Abstract: 
  • Streptococcus pyogenes (group A streptococcus [GAS]) is a major human pathogen. Attachment of GAS to host cells depends in large part on pili. These assemblies are built from multiple covalently linked subunits of a backbone protein (FctA), which for ...

    Streptococcus pyogenes (group A streptococcus [GAS]) is a major human pathogen. Attachment of GAS to host cells depends in large part on pili. These assemblies are built from multiple covalently linked subunits of a backbone protein (FctA), which forms the shaft of the pilus, and two minor pilin proteins, FctB anchoring the pilus to the cell wall and Cpa functioning as the adhesin at the tip. Polymerisation of the pilin subunits is mediated by a specific sortase, which catalyzes the formation of peptide bonds linking successive subunits. An additional gene, SipA, is also essential for GAS pilus polymerisation, but its function remains undefined. Here we report the crystal structure of a truncated SipA protein from GAS, determined at 1.67Å resolution. The structure reveals that SipA has the same core fold as the Escherichia coli type-I signal peptidase (SPase-I), but has a much smaller non-catalytic domain. The truncated protein, which lacks 9 N-terminal residues, forms an arm-swapped dimer in which the C-terminal β-strand of each monomer crosses over to interact with an N-terminal strand from the other monomer. In addition, there is no peptide binding cleft and significant differences in the putative membrane association region.


    Organizational Affiliation

    School of Biological Sciences, University of Auckland, Auckland, New Zealand. p.young@auckland.ac.nz



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
LepAA129Streptococcus pyogenesMutation(s): 0 
Gene Names: lepAsipAlepBspsBG3M98_09535GT971_00570SAMEA3918781_01140
EC: 3.4.21.89
Find proteins for Q8RP52 (Streptococcus pyogenes)
Explore Q8RP52 
Go to UniProtKB:  Q8RP52
Protein Feature View
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  • Reference Sequence
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
EDO
Query on EDO

Download CCD File 
A
1,2-ETHANEDIOL
C2 H6 O2
LYCAIKOWRPUZTN-UHFFFAOYSA-N
 Ligand Interaction
EOH
Query on EOH

Download CCD File 
A
ETHANOL
C2 H6 O
LFQSCWFLJHTTHZ-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.67 Å
  • R-Value Free: 0.215 
  • R-Value Work: 0.185 
  • R-Value Observed: 0.187 
  • Space Group: P 41 21 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 53.285α = 90
b = 53.285β = 90
c = 131.749γ = 90
Software Package:
Software NamePurpose
MAR345dtbdata collection
SHELXSphasing
REFMACrefinement
XDSdata reduction
SCALAdata scaling

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2013-06-26
    Type: Initial release
  • Version 1.1: 2013-07-24
    Changes: Database references