       Document 0114
 DOCN  M9630114
 TI    Lipid membrane fusion induced by the human immunodeficiency virus type 1
       gp41 N-terminal extremity is determined by its orientation in the lipid
       bilayer.
 DT    9603
 AU    Martin I; Schaal H; Scheid A; Ruysschaert JM; Laboratoire de
       Chimie-Physique des Macromolecules aux; Interfaces, Universite Libre de
       Bruxelles, Belgium.
 SO    J Virol. 1996 Jan;70(1):298-304. Unique Identifier : AIDSLINE
       MED/96099443
 AB    The amino-terminal extremity of the human immunodeficiency virus type 1
       transmembrane protein (gp41) is thought to play a pivotal role in the
       fusion of virus membranes with the plasma membrane of the target cell
       and in syncytium formation. Peptides with sequences taken from the human
       immunodeficiency virus type 1 gp41 fusogenic (synthetic peptides SPwt
       and SP-2) and nonfusogenic (SP-3 and SP-4) glycoproteins adopt mainly a
       beta-sheet conformation in the absence of lipid, as determined by
       attenuated total reflection Fourier transform infrared spectroscopy, and
       after interaction with large unilamellar liposomes, the beta-sheet is
       partly converted into an alpha-helical conformation. Peptides SPwt and
       SP-2 but not SP-3 or SP-4 were able to promote lipid mixing as assessed
       by fluorescence energy transfer assay and dye leakage in a vesicle
       leakage assay. By using polarized attenuated total reflection Fourier
       transform infrared spectroscopy, SPwt and SP-2 were found to adopt an
       oblique orientation in the lipid membrane whereas SP-3 and SP-4 were
       oriented nearly parallel to the plane of the membrane. These findings
       confirm the correlation between the membrane orientation of the
       alpha-helix and the lipid mixing ability in vitro. Interestingly, the
       data provide a direct correlation with the fusogenic activity of the
       parent glycoproteins in vivo.
 DE    Amino Acid Sequence  Binding Sites  Dyes  Human  HIV Envelope Protein
       gp41/CHEMISTRY/*METABOLISM  Lipid Bilayers  *Membrane Fusion  Molecular
       Sequence Data  Protein Conformation  Spectroscopy, Fourier Transform
       Infrared  Support, Non-U.S. Gov't  JOURNAL ARTICLE

       SOURCE: National Library of Medicine.  NOTICE: This material may be
       protected by Copyright Law (Title 17, U.S.Code).

