The HIV-1 gp41 envelope glycoprotein promotes fusion of the virus and cell membranes through the formation of a trimer-of-hairpins structure, in which the amino- and carboxyl-terminal regions of the gp41 ectodomain are brought together. Synthetic peptides derived from these two regions (called N and C peptides, respectively) inhibit HIV-1 entry. In contrast to C peptides, which inhibit in the n...

The HIV-1 gp41 envelope protein mediates membrane fusion that leads to virus entry into the cell. The core structure of fusion-active gp41 is a six-helix bundle in which an N-terminal three-stranded coiled coil is surrounded by a sheath of antiparallel C-terminal helices. A conserved glutamine (Gln 652) buried in this helical interface replaced by leucine increases HIV-1 infectivity. To define ...

The gp41 envelope protein of human immunodeficiency virus type 1 (HIV-1) contains an alpha-helical core structure responsible for mediating membrane fusion during viral entry. Recent studies suggest that a conserved hydrophobic cavity in the coiled coil of this core plays a distinctive structural role in maintaining the fusogenic conformation of the gp41 molecule. Here we investigated the impor...

envelope complexreadily undergoes receptor-activated The human immunodeficiency virus type 1 (HIV-1) is conformational change suggests that its native state is an enveloped virus, and its envelope protein complex metastable, again similar to the pH-activated envelope controls the key process of viral entry. This envelope protein of influenza virus (Carr et al., 1997). That is, protein determine...

The gp41 envelope protein mediates the entry of primate immunodeficiency viruses into target cells by promoting the fusion of viral and cellular membranes. The structure of the gp41 ectodomain core represents a trimer of identical helical hairpins in which a central trimeric coiled-coil made up of three amino-terminal helices is wrapped in an outer layer of three antiparallel carboxyl-terminal ...

Fusion between viral and host cell membranes is the initial step of human immunodeficiency virus infection and is mediated by the gp41 protein, which is embedded in the viral membrane. The approximately 20-residue N-terminal fusion peptide (FP) region of gp41 binds to the host cell membrane and plays a critical role in fusion catalysis. Key gp41 fusion conformations include an early pre-hairpin...

The membrane fusion process mediated by the gp41 transmembrane envelope glycoprotein of the human immunodeficiency virus type 1 (HIV-1) was addressed by a flow cytometry assay detecting exchanges of fluorescent membrane probes (DiI and DiO) between cells expressing the HIV-1 envelope proteins (Env) and target cells. Double-fluorescent cells were detected when target cells expressed the type of ...

The transmembrane envelope protein gp41 of the human immunodeficiency virus HIV-1 plays an important role during infection allowing fusion of the viral and cellular membrane. In addition, there is increasing evidence that gp41 may contribute to the immunodeficiency induced by HIV-1. Recombinant gp41 and a synthetic peptide corresponding to a highly conserved domain in gp41, the immunosuppressiv...

Induction of effective antibody responses against HIV-1 infection remains an elusive goal for vaccine development. Progress may require in-depth understanding of the molecular mechanisms of neutralization by monoclonal antibodies. We have analyzed the molecular actions of two rare, broadly neutralizing, human monoclonal antibodies, 4E10 and 2F5, which target the transiently exposed epitopes in ...

A peptide construct (FPtr) was synthesized which mimics the biologically relevant topology of fusion peptide (FP) domains of the trimeric HIV-1 gp41 envelope protein. The FP domains play a critical role in gp41-catalyzed fusion of viral and host cell membranes which is a key step in viral infection. The FPtr construct contains three FP strands chemically bonded at their C-termini through lysine...