1UWX

P1.2 serosubtype antigen derived from N. meningitidis PorA in complex with Fab fragment


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.2 Å
  • R-Value Free: 0.265 
  • R-Value Work: 0.223 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Structural Variation and Immune Recognition of the P1.2 Subtype Meningococcal Antigen.

Tzitzilonis, C.Prince, S.M.Collins, R.F.Achtman, M.Feavers, I.M.Maiden, M.C.J.Derrick, J.P.

(2005) Proteins: Struct., Funct., Bioinf. 62: 947

  • DOI: 10.1002/prot.20800

  • PubMed Abstract: 
  • Neisseria meningitidis is a globally important cause of bacterial meningitis and septicemia. No comprehensive antimeningococcal vaccine is available, largely as a consequence of the high sequence diversity of those surface proteins that could functio ...

    Neisseria meningitidis is a globally important cause of bacterial meningitis and septicemia. No comprehensive antimeningococcal vaccine is available, largely as a consequence of the high sequence diversity of those surface proteins that could function as components of a vaccine. One such component is the protein PorA, a major surface porin of this Gram-negative organism that has been used in a number of experimental and licensed vaccines. Here we describe a series of experiments designed to investigate the consequences for antibody recognition of sequence diversity within a PorA antigen. The binding of a 14-residue peptide, corresponding to the P1.2 subtype antigen, to the MN16C13F4 monoclonal antibody was sensitive to mutation of five out of the six residues within the epitope sequence. The crystal structure of the antibody Fab fragment, determined in complex with the peptide antigen, shows a remarkably hydrophobic binding site and interactions between the antigen and antibody are dominated by apolar residues. Nine intrachain hydrogen bonds are formed within the antigen which maintain the beta-hairpin conformation of the peptide. These hydrogen bonds involve residues that are highly conserved amongst different P1.2 sequence variants, suggesting that some positions may be conserved for structural reasons in these highly polymorphic regions. The sensitivity of antibody recognition of the antigen towards mutation provides a structural explanation for the widespread sequence variation seen in different PorA sequences in this region. Single point mutations are sufficient to remove binding capability, providing a rationale for the manner in which different meningococcal PorA escape variants arise.


    Organizational Affiliation

    Faculty of Life Sciences, The University of Manchester, Manchester, United Kingdom.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
PROTEIN G-PRIME
A, B
63Streptococcus sp. group GMutation(s): 1 
Gene Names: spg
Find proteins for P19909 (Streptococcus sp. group G)
Go to UniProtKB:  P19909
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
ANTIBODY
H, M
225N/AMutation(s): 0 
Protein Feature View is not available: No corresponding UniProt sequence found.
Entity ID: 3
MoleculeChainsSequence LengthOrganismDetails
ANTIBODY
K, L
213Mus musculusMutation(s): 0 
Gene Names: Igkc
Find proteins for P01837 (Mus musculus)
Go to UniProtKB:  P01837
Entity ID: 4
MoleculeChainsSequence LengthOrganismDetails
CLASS 1 OUTER MEMBRANE PROTEIN VARIABLE REGION 2
P, Q
13Neisseria meningitidisMutation(s): 0 
Gene Names: porA
Find proteins for Q9JPT2 (Neisseria meningitidis)
Go to UniProtKB:  Q9JPT2
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.2 Å
  • R-Value Free: 0.265 
  • R-Value Work: 0.223 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 81.426α = 90.00
b = 110.568β = 90.00
c = 138.734γ = 90.00
Software Package:
Software NamePurpose
SCALAdata scaling
AMoREphasing
REFMACrefinement
MOSFLMdata reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2005-06-15
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Refinement description, Version format compliance