PDBsum entry 1df4

Viral protein

PDB id: 1df4

Contents

Protein chain

57 a.a. *

Waters ×77

* Residue conservation analysis

PDB id:

1df4

Name:

Viral protein

Title:

Interactions between HIV-1 gp41 core and detergents and their implications for membrane fusion

Structure:

HIV-1 envelope glycoprotein gp41. Chain: a. Fragment: residues 1 - 34 and 41 - 68 connected by a six-residue linker (ser-gly-gly-arg- gly-gly). Engineered: yes

Source:

Human immunodeficiency virus 1. Organism_taxid: 11676. Expressed in: escherichia coli. Expression_system_taxid: 562. Other_details: recombinant gp41 with linker (ser-gly-gly- arg-gly- gly) between two fragments

Biol. unit:

Trimer (from PDB file)

Resolution:

1.45Å R-factor: 0.200 R-free: 0.245

Authors:

W.Shu,H.Ji,M.Lu

Key ref:

W.Shu et al. (2000). Interactions between HIV-1 gp41 core and detergents and their implications for membrane fusion. J Biol Chem, 275, 1839-1845. PubMed id: 10636883 DOI: 10.1074/jbc.275.3.1839

Date:

17-Nov-99 Release date: 24-Nov-99

Protein chain

P04578  (ENV_HV1H2) -  Envelope glycoprotein gp160 from Human immunodeficiency virus type 1 group M subtype B (isolate HXB2)

Seq: 856 a.a.

Struc: 57 a.a.*

* PDB and UniProt seqs differ at 1 residue position (black cross)

Enzyme reactions

• Enzyme class: E.C.?

DOI no: 10.1074/jbc.275.3.1839

J Biol Chem 275:1839-1845 (2000)

PubMed id: 10636883

Interactions between HIV-1 gp41 core and detergents and their implications for membrane fusion.

W.Shu, H.Ji, M.Lu.

ABSTRACT

The gp41 envelope protein mediates entry of human immunodeficiency virus type 1 (HIV-1) into the cell by promoting membrane fusion. The crystal structure of a gp41 ectodomain core in its fusion-active state is a six-helix bundle in which a N-terminal trimeric coiled coil is surrounded by three C-terminal outer helices in an antiparallel orientation. Here we demonstrate that the N34(L6)C28 model of the gp41 core is stabilized by interaction with the ionic detergent sodium dodecyl sulfate (SDS) or the nonionic detergent n-octyl-beta-D-glucopyranoside (betaOG). The high resolution x-ray structures of N34(L6)C28 crystallized from two different detergent micellar media reveal a six-helix bundle conformation very similar to that of the molecule in water. Moreover, N34(L6)C28 adopts a highly alpha-helical conformation in lipid vesicles. Taken together, these results suggest that the six-helix bundle of the gp41 core displays substantial affinity for lipid bilayers rather than unfolding in the membrane environment. This characteristic may be important for formation of the fusion-active gp41 core structure and close apposition of the viral and cellular membranes for fusion.

Selected figure(s)

Figure 1.
Fig. 1. HIV-1 gp41 core structure. A schematic diagram of gp41 showing the important functional regions of the ectodomain. The amino acid sequences of the N34 and C28 segments are shown. The N34(L6)C28 model of the gp41 core consists of N34 and C28 plus a linker of six hydrophilic residues. The disulfide bond and four potential N-glycosylation sites are depicted. The residues are numbered according to their position in gp160.

Figure 7.
Fig. 7. Stereo view of the superposition of residues 564-571 of N34 and 628-633 of C28 in the N34(L6)C28 structures in water (red), SDS (green), and OG (white), showing a cross-section of helix packing near the conserved hydrophobic cavity in the gp41 core. Figure was generated with the program SETOR (56).

The above figures are reprinted by permission from the ASBMB: J Biol Chem (2000, 275, 1839-1845) copyright 2000.

Figures were selected by an automated process.