5I0Q

Structure of human C4b-binding protein alpha chain CCP domains 1 and 2 in complex with the hypervariable region of mutant group A Streptococcus M2 (K65A, N66A) protein


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.29 Å
  • R-Value Free: 0.224 
  • R-Value Work: 0.203 
  • R-Value Observed: 0.205 

wwPDB Validation   3D Report Full Report


This is version 1.1 of the entry. See complete history


Literature

Conserved patterns hidden within group A Streptococcus M protein hypervariability recognize human C4b-binding protein.

Buffalo, C.Z.Bahn-Suh, A.J.Hirakis, S.P.Biswas, T.Amaro, R.E.Nizet, V.Ghosh, P.

(2016) Nat Microbiol 1: 16155-16155

  • DOI: 10.1038/nmicrobiol.2016.155
  • Primary Citation of Related Structures:  
    5HYP, 5HYT, 5HYU, 5HZP, 5I0Q

  • PubMed Abstract: 
  • No vaccine exists against group A Streptococcus (GAS), a leading cause of worldwide morbidity and mortality. A severe hurdle is the hypervariability of its major antigen, the M protein, with >200 different M types known. Neutralizing antibodies typically recognize M protein hypervariable regions (HVRs) and confer narrow protection ...

    No vaccine exists against group A Streptococcus (GAS), a leading cause of worldwide morbidity and mortality. A severe hurdle is the hypervariability of its major antigen, the M protein, with >200 different M types known. Neutralizing antibodies typically recognize M protein hypervariable regions (HVRs) and confer narrow protection. In stark contrast, human C4b-binding protein (C4BP), which is recruited to the GAS surface to block phagocytic killing, interacts with a remarkably large number of M protein HVRs (apparently ∼90%). Such broad recognition is rare, and we discovered a unique mechanism for this through the structure determination of four sequence-diverse M proteins in complexes with C4BP. The structures revealed a uniform and tolerant 'reading head' in C4BP, which detected conserved sequence patterns hidden within hypervariability. Our results open up possibilities for rational therapies that target the M-C4BP interaction, and also inform a path towards vaccine design.


    Organizational Affiliation

    Department of Chemistry &Biochemistry, University of California, San Diego, La Jolla, California 92093, USA.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
M protein, serotype 2.1A104Streptococcus pyogenesMutation(s): 2 
Gene Names: emmL2.1
UniProt
Find proteins for P50468 (Streptococcus pyogenes)
Explore P50468 
Go to UniProtKB:  P50468
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP50468
Protein Feature View
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  • Reference Sequence
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetailsImage
C4b-binding protein alpha chainB128Homo sapiensMutation(s): 0 
Gene Names: C4BPAC4BP
UniProt & NIH Common Fund Data Resources
Find proteins for P04003 (Homo sapiens)
Explore P04003 
Go to UniProtKB:  P04003
PHAROS:  P04003
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP04003
Protein Feature View
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.29 Å
  • R-Value Free: 0.224 
  • R-Value Work: 0.203 
  • R-Value Observed: 0.205 
  • Space Group: P 43 3 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 148.598α = 90
b = 148.598β = 90
c = 148.598γ = 90
Software Package:
Software NamePurpose
PHENIXrefinement
HKL-2000data reduction
HKL-2000data scaling
PHENIXphasing

Structure Validation

View Full Validation Report




Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2016-07-20
    Type: Initial release
  • Version 1.1: 2016-10-26
    Changes: Database references