4P0D

The T6 backbone pilin of serotype M6 Streptococcus pyogenes has a modular three-domain structure decorated with variable loops and extensions


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.90 Å
  • R-Value Free: 0.250 
  • R-Value Work: 0.209 
  • R-Value Observed: 0.211 

wwPDB Validation   3D Report Full Report


This is version 1.1 of the entry. See complete history


Literature

Structural Conservation, Variability, and Immunogenicity of the T6 Backbone Pilin of Serotype M6 Streptococcus pyogenes.

Young, P.G.Moreland, N.J.Loh, J.M.Bell, A.Atatoa Carr, P.Proft, T.Baker, E.N.

(2014) Infect Immun 82: 2949-2957

  • DOI: https://doi.org/10.1128/IAI.01706-14
  • Primary Citation of Related Structures:  
    4P0D

  • PubMed Abstract: 

    Group A streptococcus (GAS; Streptococcus pyogenes) is a Gram-positive human pathogen that causes a broad range of diseases ranging from acute pharyngitis to the poststreptococcal sequelae of acute rheumatic fever. GAS pili are highly diverse, long protein polymers that extend from the cell surface. They have multiple roles in infection and are promising candidates for vaccine development. This study describes the structure of the T6 backbone pilin (BP; Lancefield T-antigen) from the important M6 serotype. The structure reveals a modular arrangement of three tandem immunoglobulin-like domains, two with internal isopeptide bonds. The T6 pilin lysine, essential for polymerization, is located in a novel VAKS motif that is structurally homologous to the canonical YPKN pilin lysine in other three- and four-domain Gram-positive pilins. The T6 structure also highlights a conserved pilin core whose surface is decorated with highly variable loops and extensions. Comparison to other Gram-positive BPs shows that many of the largest variable extensions are found in conserved locations. Studies with sera from patients diagnosed with GAS-associated acute rheumatic fever showed that each of the three T6 domains, and the largest of the variable extensions (V8), are targeted by IgG during infection in vivo. Although the GAS BP show large variations in size and sequence, the modular nature of the pilus proteins revealed by the T6 structure may aid the future design of a pilus-based vaccine.


  • Organizational Affiliation

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


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Trypsin-resistant surface T6 protein489Streptococcus pyogenes MGAS10394Mutation(s): 1 
Gene Names: tee6M6_Spy0160
UniProt
Find proteins for P18481 (Streptococcus pyogenes serotype M6 (strain ATCC BAA-946 / MGAS10394))
Explore P18481 
Go to UniProtKB:  P18481
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP18481
Sequence Annotations
Expand
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.90 Å
  • R-Value Free: 0.250 
  • R-Value Work: 0.209 
  • R-Value Observed: 0.211 
  • Space Group: P 63
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 104.24α = 90
b = 104.24β = 90
c = 84.22γ = 120
Software Package:
Software NamePurpose
XDSdata reduction
SCALAdata scaling
PHASERphasing
REFMACrefinement
PDB_EXTRACTdata extraction
XSCALEdata reduction
Aimlessdata scaling

Structure Validation

View Full Validation Report



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
Health Research CouncilNew Zealand--

Revision History  (Full details and data files)

  • Version 1.0: 2014-08-27
    Type: Initial release
  • Version 1.1: 2023-12-20
    Changes: Data collection, Database references, Derived calculations, Refinement description