title: Conformation and interaction with the membrane models of the amino-terminal peptide of influenza virus hemagglutinin HA2 at fusion pH.
abstract: Conformations of a 48-mer peptide corresponding to the amino-terminal region of influenza HA2 in aqueous and membranous environments were studied. In aqueous solution the peptide was found to be oligomeric and its helicity was enhanced at higher concentrations. The conformation in phospholipid bilayer and insertion depth into the sodium dodecyl sulfate (SDS) micelle for the fusion peptide were in line with those determined for the amino-terminal 25-mer analog. The turn of residues 28-31 found in the crystal structure of hemagglutinin at neutral pH persisted in the presence of SDS at pH 5.0. Except for the turn, conformational lability of the amino portion of HA2 is suggested by comparison of the secondary structure determined herein with that obtained with the influenza fusion protein crystallized in the aqueous phase at neutral pH. The backbone amide proton exchange experiment suggested an interaction with the micellar surface for the segment carboxy-terminal to the fusion peptide domain.
authors.affiliation: Institute of Chemistry, Academia Sinica, Taipei, Taiwan, 115, Republic of China. dkc@chem.sinica.edu.tw
authors.forename: D K
authors.initials: DK
authors.lastname: Chang
authors.forename: S F
authors.initials: SF
authors.lastname: Cheng
authors.forename: V D
authors.initials: VD
authors.lastname: Trivedi
mesh_terms: D000595:Amino Acid Sequence; D002942:Circular Dichroism; D005453:Fluorescence; D019267:Hemagglutinin Glycoproteins, Influenza Virus; D006388:Hemagglutinins / Q000737:chemistry* / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D037102:Lectins; D008051:Lipid Bilayers / Q000737:chemistry*; D008823:Micelles; D008969:Molecular Sequence Data; D019906:Nuclear Magnetic Resonance, Biomolecular; D009975:Orthomyxoviridae / Q000737:chemistry* / Q000472:pathogenicity; D010446:Peptide Fragments / Q000737:chemistry* / Q000378:metabolism; D010743:Phospholipids; D011485:Protein Binding; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D012967:Sodium Dodecyl Sulfate; D014764:Viral Proteins
chemical_list: D019267:Hemagglutinin Glycoproteins, Influenza Virus; D006388:Hemagglutinins; D037102:Lectins; D008051:Lipid Bilayers; D008823:Micelles; D010446:Peptide Fragments; D010743:Phospholipids; D014764:Viral Proteins; C442835:influenza virus-hemagglutinin peptide 2 (1-48); D012967:Sodium Dodecyl Sulfate