4M1D

Crystal structure of anti-HIV-1 Fab 447-52D in complex with V3 cyclic peptide MN


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.8 Å
  • R-Value Free: 0.216 
  • R-Value Work: 0.186 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Thermodynamic Signatures of the Antigen Binding Site of mAb 447-52D Targeting the Third Variable Region of HIV-1 gp120.

Killikelly, A.Zhang, H.T.Spurrier, B.Williams, C.Gorny, M.K.Zolla-Pazner, S.Kong, X.P.

(2013) Biochemistry 52: 6249-6257

  • DOI: 10.1021/bi400645e

  • PubMed Abstract: 
  • The third variable region (V3) of HIV-1 gp120 plays a key role in viral entry into host cells; thus, it is a potential target for vaccine design. Human monoclonal antibody (mAb) 447-52D is one of the most broadly and potently neutralizing anti-V3 mAb ...

    The third variable region (V3) of HIV-1 gp120 plays a key role in viral entry into host cells; thus, it is a potential target for vaccine design. Human monoclonal antibody (mAb) 447-52D is one of the most broadly and potently neutralizing anti-V3 mAbs. We further characterized the 447-52D epitope by determining a high-resolution crystal structure of the Fab fragment in complex with a cyclic V3 and interrogated the antigen-antibody interaction by a combination of site-specific mutagenesis, isothermal titration calorimetry (ITC) and neutralization assays. We found that 447-52D's neutralization capability is correlated with its binding affinity and at 25 °C the Gibbs free binding energy is composed of a large enthalpic component and a small favorable entropic component. The large enthalpic contribution is due to (i) an extensive hydrogen bond network, (ii) a π-cation sandwiching the V3 crown apex residue Arg(315), and (iii) a salt bridge between the 447-52D heavy chain residue Asp(H95) and Arg(315). Arg(315) is often harbored by clade B viruses; thus, our data explained why 447-52D preferentially neutralizes clade B viruses. Interrogation of the thermodynamic signatures of residues at the antigen binding interface gives key insights into their contributions in the antigen-antibody interaction.


    Organizational Affiliation

    Departments of Biochemistry and Molecular Pharmacology and ‡Department of Pathology, New York University School of Medicine , New York, New York 10016, United States.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Fab mAb 447-52D Light Chain
L, M
216Homo sapiensN/A
Find proteins for A2NUT2 (Homo sapiens)
Go to UniProtKB:  A2NUT2
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Fab mAb 447-52D Heavy Chain
H, I
231N/AN/A
Protein Feature View is not available: No corresponding UniProt sequence found.
Entity ID: 3
MoleculeChainsSequence LengthOrganismDetails
Cyclic V3 Arch Peptide
P, Q
14Human immunodeficiency virus type 1 group M subtype BGene Names: env
Find proteins for P05877 (Human immunodeficiency virus type 1 group M subtype B)
Go to UniProtKB:  P05877
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
GOL
Query on GOL

Download SDF File 
Download CCD File 
H, I, L, M
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: 1.8 Å
  • R-Value Free: 0.216 
  • R-Value Work: 0.186 
  • Space Group: C 1 2 1
Unit Cell:
Length (Å)Angle (°)
a = 179.836α = 90.00
b = 59.781β = 127.35
c = 137.066γ = 90.00
Software Package:
Software NamePurpose
HKL-2000data collection
HKL-2000data scaling
PHENIXrefinement
MOLREPphasing
HKL-2000data reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2013-09-04
    Type: Initial release
  • Version 1.1: 2013-12-25
    Type: Database references