Biological Assembly 1  

 3D View: Structure | Electron Density | Ligand Interaction

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Hetero 3-mer - A1BC Pseudo Symmetry: Asymmetric - C1 
Pseudo Stoichiometry: Hetero 3-mer - A2B1 

Biological assembly 1 assigned by authors and generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 51.09 kDa 
• Atom Count: 4404 
• Residue Count: 449 
• Unique protein chains: 3

4XCF

Crystal structure of human 4E10 Fab in complex with its peptide epitope on HIV-1 gp41; crystals cryoprotected with phosphatidylcholine (03:0 PC)

• DOI: 10.2210/pdb4XCF/pdb

• Classification: IMMUNE SYSTEM
• Organism(s): Homo sapiens, Human immunodeficiency virus 1
• Expression System: Homo sapiens
• Mutation(s): No 


• Deposited: 2014-12-17 Released: 2016-02-03 
• Deposition Author(s): Irimia, A., Stanfield, R.L., Wilson, I.A.
• Funding Organization(s): National Institutes of Health/National Institute Of Allergy and Infectious Diseases (NIH/NIAID)

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.43 Å
• R-Value Free: 0.170 
• R-Value Work: 0.137 
• R-Value Observed: 0.138 

Literature

Crystallographic Identification of Lipid as an Integral Component of the Epitope of HIV Broadly Neutralizing Antibody 4E10.

Irimia, A., Sarkar, A., Stanfield, R.L., Wilson, I.A.

(2016) Immunity 44: 21-31

• PubMed: 26777395 
• DOI: 10.1016/j.immuni.2015.12.001
• Structures With Same Primary Citation


• PubMed Abstract: 
  

Numerous studies of the anti-HIV-1 envelope glycoprotein 41 (gp41) broadly neutralizing antibody 4E10 suggest that 4E10 also interacts with membrane lipids, but the antibody regions contacting lipids and its orientation with respect to the viral membrane are unknown. Vaccine immunogens capable of re-eliciting these membrane proximal external region (MPER)-like antibodies may require a lipid component to be successful. We performed a systematic crystallographic study of lipid binding to 4E10 to identify lipids bound by the antibody and the lipid-interacting regions. We identified phosphatidic acid, phosphatidylglycerol, and glycerol phosphate as specific ligands for 4E10 in the crystal structures. 4E10 used its CDRH1 loop to bind the lipid head groups, while its CDRH3 interacted with the hydrophobic lipid tails. Identification of the lipid binding sites on 4E10 may aid design of immunogens for vaccines that include a lipid component in addition to the MPER on gp41 for generation of broadly neutralizing antibodies.

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Organizational Affiliation: 

Department of Integrative Structural and Computational Biology, International AIDS Vaccine Initiative Neutralizing Antibody Center, Collaboration for AIDS Vaccine Discovery (CAVD), and Scripps Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery (CHAVI-ID), The Scripps Research Institute, La Jolla, CA 92037, USA. Electronic address: [e-mail].

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details
4E10 Fab light chain	L	215	Homo sapiens	Mutation(s): 0

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details
4E10 Fab heavy chain	H	228	Homo sapiens	Mutation(s): 0

Entity ID: 3
Molecule	Chains	Sequence Length	Organism	Details
MODIFIED FRAGMENT OF HIV-1 GLYCOPROTEIN (GP41) INCLUDING THE MPER REGION 671-683	P	16	Human immunodeficiency virus 1	Mutation(s): 0
Find proteins for P05877 (Human immunodeficiency virus type 1 group M subtype B (isolate MN)) Explore P05877  Go to UniProtKB:  P05877

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
43Y	H, L	[(2R)-3-[oxidanyl-[2-(trimethyl-$l^{4}-azanyl)ethoxy]phosphoryl]oxy-2-propanoyloxy-propyl] propanoate C14 H29 N O8 P LMBVWVMURYPSQM-GFCCVEGCSA-O

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.43 Å
• R-Value Free: 0.170 
• R-Value Work: 0.137 
• R-Value Observed: 0.138 
• Space Group: C 1 2 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 156.76	α = 90
b = 44.588	β = 113.53
c = 85.153	γ = 90

Software Package:

Software Name	Purpose
PHENIX	refinement
HKL-2000	data reduction
HKL-2000	data scaling
PHASER	phasing

Structure Validation

Entry History & Funding Information

Deposition Data

• Deposited Date: 2014-12-17 
• Released Date: 2016-02-03 
Deposition Author(s): Irimia, A., Stanfield, R.L., Wilson, I.A.

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Funding Organization	Location	Grant Number
National Institutes of Health/National Institute Of Allergy and Infectious Diseases (NIH/NIAID)	United States	R01 AI084817

Revision History 

• Version 1.0: 2016-02-03
  Type: Initial release
  
• Version 1.1: 2017-09-06
  Changes: Author supporting evidence, Database references, Derived calculations
• Version 1.2: 2019-12-11
  Changes: Author supporting evidence