1YWM

Crystal structure of the N-terminal domain of group B Streptococcus alpha C protein


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.86 Å
  • R-Value Free: 0.233 
  • R-Value Work: 0.188 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Crystal structure of the N-terminal domain of the group B streptococcus alpha C protein.

Auperin, T.C.Bolduc, G.R.Baron, M.J.Heroux, A.Filman, D.J.Madoff, L.C.Hogle, J.M.

(2005) J.Biol.Chem. 280: 18245-18252

  • DOI: 10.1074/jbc.M412391200

  • PubMed Abstract: 
  • Group B Streptococcus (GBS) is the leading cause of bacterial pneumonia, sepsis, and meningitis among neonates and an important cause of morbidity among pregnant women and immunocompromised adults. Invasive diseases due to GBS are attributed to the a ...

    Group B Streptococcus (GBS) is the leading cause of bacterial pneumonia, sepsis, and meningitis among neonates and an important cause of morbidity among pregnant women and immunocompromised adults. Invasive diseases due to GBS are attributed to the ability of the pathogen to translocate across human epithelial surfaces. The alpha C protein (ACP) has been identified as an invasin that plays a role in internalization and translocation of GBS across epithelial cells. The soluble N-terminal domain of ACP (NtACP) blocks the internalization of GBS. We determined the 1.86-A resolution crystal structure of NtACP comprising residues Ser(52) through Leu(225) of the full-length ACP. NtACP has two domains, an N-terminal beta-sandwich and a C-terminal three-helix bundle. Structural and topological alignments reveal that the beta-sandwich shares structural elements with the type III fibronectin fold (FnIII), but includes structural elaborations that make it unique. We have identified a potential integrin-binding motif consisting of Lys-Thr-Asp(146), Arg(110), and Asp(118). A similar arrangement of charged residues has been described in other invasins. ACP shows a heparin binding activity that requires NtACP. We propose a possible heparin-binding site, including one surface of the three-helix bundle, and nearby portions of the sandwich and repeat domains. We have validated this prediction using assays of the heparin binding and cell-adhesion properties of engineered fragments of ACP. This is the first crystal structure of a member of the highly conserved Gram-positive surface alpha-like protein family, and it will enable the internalization mechanism of GBS to be dissected at the atomic level.


    Related Citations: 
    • The Alpha C Protein Mediates Internalization of Group B Streptococcus within Human Cervical Epithelial Cells
      Bolduc, G.R.,Baron, M.J.,Gravekamp, C.,Lachenauer, C.S.,Madoff, L.C.
      (2002) Cell.Microbiol. 4: 751
    • Large, Identical, Tandem Repeating Units in the C Protein Alpha Antigen Gene, Bca, of Group B Streptococci
      Michel, J.L.,Madoff, L.C.,Olson, K.,Kling, D.E.,Kasper, D.L.,Ausubel, F.M.
      (1992) Proc.Natl.Acad.Sci.USA 89: 10060
    • Alpha C Protein of Group B Streptococcus Binds Host Cell Surface Glycosaminoglycan and Enters Cells by an Actin-Dependent Mechanism
      Baron, M.J.,Bolduc, G.R.,Goldberg, M.B.,Auperin, T.C.,Madoff, L.C.
      (2004) J.Biol.Chem. 279: 24714


    Organizational Affiliation

    Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
C protein alpha-antigen
A
200Streptococcus agalactiae serotype Ia (strain ATCC 27591 / A909 / CDC SS700)Mutation(s): 0 
Gene Names: bca
Find proteins for Q02192 (Streptococcus agalactiae serotype Ia (strain ATCC 27591 / A909 / CDC SS700))
Go to UniProtKB:  Q02192
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
DTU
Query on DTU

Download SDF File 
Download CCD File 
A
(2R,3S)-1,4-DIMERCAPTOBUTANE-2,3-DIOL
C4 H10 O2 S2
VHJLVAABSRFDPM-ZXZARUISSA-N
 Ligand Interaction
GOL
Query on GOL

Download SDF File 
Download CCD File 
A
GLYCEROL
GLYCERIN; PROPANE-1,2,3-TRIOL
C3 H8 O3
PEDCQBHIVMGVHV-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.86 Å
  • R-Value Free: 0.233 
  • R-Value Work: 0.188 
  • Space Group: P 61 2 2
Unit Cell:
Length (Å)Angle (°)
a = 56.464α = 90.00
b = 56.464β = 90.00
c = 271.617γ = 120.00
Software Package:
Software NamePurpose
DENZOdata reduction
SCALEPACKdata scaling
REFMACrefinement
EPMRphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2005-03-08
    Type: Initial release
  • Version 1.1: 2008-04-30
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Source and taxonomy, Version format compliance