Biological Assembly 1  

 3D View: Structure

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 8.29 kDa 
• Atom Count: 555 
• Residue Count: 68 
• Unique protein chains: 1

2MK3

Solution NMR structure of gp41 ectodomain monomer on a DPC micelle

• DOI: 10.2210/pdb2MK3/pdb
• BMRB: 19750

• Classification: IMMUNE SYSTEM
• Organism(s): Human immunodeficiency virus 1
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2014-01-23 Released: 2014-02-19 
• Deposition Author(s): Roche, J., Louis, J.M., Grishaev, A., Ying, J., Bax, A.

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Experimental Data Snapshot

• Method: SOLUTION NMR
• Conformers Calculated: 30 
• Conformers Submitted: 20 
• Selection Criteria: structures with the lowest energy 

Literature

Dissociation of the trimeric gp41 ectodomain at the lipid-water interface suggests an active role in HIV-1 Env-mediated membrane fusion.

Roche, J., Louis, J.M., Grishaev, A., Ying, J., Bax, A.

(2014) Proc Natl Acad Sci U S A 111: 3425-3430

• PubMed: 24550514 
• DOI: 10.1073/pnas.1401397111
• Primary Citation of Related Structures:  
  2MK3


• PubMed Abstract: 
  

The envelope glycoprotein gp41 mediates the process of membrane fusion that enables entry of the HIV-1 virus into the host cell. The actual fusion process involves a switch from a homotrimeric prehairpin intermediate conformation, consisting of parallel coiled-coil helices, to a postfusion state where the ectodomains are arranged as a trimer of helical hairpins, adopting a six-helix bundle (6HB) state. Here, we show by solution NMR spectroscopy that a water-soluble 6HB gp41 ectodomain binds to zwitterionic detergents that contain phosphocholine or phosphatidylcholine head groups and phospholipid vesicles that mimic T-cell membrane composition. Binding results in the dissociation of the 6HB and the formation of a monomeric state, where its two α-helices, N-terminal heptad repeat (NHR) and C-terminal heptad repeat (CHR), become embedded in the lipid-water interface of the virus and host cell. The atomic structure of the gp41 ectodomain monomer, based on NOE distance restraints and residual dipolar couplings, shows that the NHR and CHR helices remain mostly intact, but they completely lose interhelical contacts. The high affinity of the ectodomain helices for phospholipid surfaces suggests that unzippering of the prehairpin intermediate leads to a state where the NHR and CHR helices become embedded in the host cell and viral membranes, respectively, thereby providing a physical force for bringing these membranes into close juxtaposition before actual fusion.

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Organizational Affiliation: 

Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Transmembrane glycoprotein, chimeric construct	A	72	Human immunodeficiency virus 1	Mutation(s): 0
Find proteins for D0VWW0 (Human immunodeficiency virus 1) Explore D0VWW0  Go to UniProtKB:  D0VWW0

Experimental Data & Validation

Experimental Data

• Method: SOLUTION NMR
• Conformers Calculated: 30 
• Conformers Submitted: 20 
• Selection Criteria: structures with the lowest energy 
• OLDERADO: 2MK3 Olderado

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2014-01-23 
• Released Date: 2014-02-19 
Deposition Author(s): Roche, J., Louis, J.M., Grishaev, A., Ying, J., Bax, A.

Revision History 

• Version 1.0: 2014-02-19
  Type: Initial release
  
• Version 1.1: 2014-03-19
  Changes: Database references