1RHH

Crystal Structure of the Broadly HIV-1 Neutralizing Fab X5 at 1.90 Angstrom Resolution


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.9 Å
  • R-Value Free: 0.227 
  • R-Value Work: 0.224 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Crystal Structure of the Broadly Cross-Reactive HIV-1-Neutralizing Fab X5 and Fine Mapping of Its Epitope

Darbha, R.Phogat, S.Labrijn, A.F.Shu, Y.Gu, Y.Andrykovitch, M.Zhang, M.Y.Pantophlet, R.Martin, L.Vita, C.Burton, D.R.Dimitrov, D.S.Ji, X.

(2004) Biochemistry 43: 1410-1417

  • DOI: 10.1021/bi035323x

  • PubMed Abstract: 
  • The human monoclonal antibody Fab X5 neutralizes a broad range of HIV-1 primary isolates. The crystal structure of X5 has been determined at 1.9 A resolution. There are two crystallographically independent Fab fragments in the asymmetric unit. The cr ...

    The human monoclonal antibody Fab X5 neutralizes a broad range of HIV-1 primary isolates. The crystal structure of X5 has been determined at 1.9 A resolution. There are two crystallographically independent Fab fragments in the asymmetric unit. The crystallographic R value for the final model is 0.22. The antibody-combining site features a long (22 amino acid residues) CDR H3 with a protruding hook-shaped motif. The X5 structure and site-directed mutagenesis data suggest that X5 amino acid residues W100 and Y100F in the CDR H3 motif may be critical for the binding of Fab X5 to gp120. X5 bound to a complex of a CD4 mimetic and gp120 with approximately the same kinetics and affinity as to a CD4-gp120 complex, suggesting that specific interactions between CD4 and X5 are unlikely to contribute to the binding of X5 to gp120-CD4 complexes. Binding of X5 to alanine scanning mutants of gp120JR-CSF complexed with CD4 suggested a critical role of the highly conserved amino acid residues at positions 423 and 432. The X5 structure and fine mapping of its epitope may assist in the elucidation of the mechanisms of viral entry and neutralization, and the development of HIV-1 inhibitors and vaccines.


    Organizational Affiliation

    Macromolecular Crystallography Laboratory, National Cancer Institute, Frederick, Maryland 21702, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Fab X5, light chain
A, C
215N/AMutation(s): 0 
Protein Feature View is not available: No corresponding UniProt sequence found.
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Fab X5, heavy chain
B, D
239N/AMutation(s): 0 
Protein Feature View is not available: No corresponding UniProt sequence found.
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.9 Å
  • R-Value Free: 0.227 
  • R-Value Work: 0.224 
  • Space Group: P 4 21 2
Unit Cell:
Length (Å)Angle (°)
a = 139.600α = 90.00
b = 139.600β = 90.00
c = 120.340γ = 90.00
Software Package:
Software NamePurpose
AMoREphasing
SCALEPACKdata scaling
DENZOdata reduction
CNSrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2004-02-24
    Type: Initial release
  • Version 1.1: 2008-04-29
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance