Collect. Czech. Chem. Commun. 1996, 61, 742-750

Conformational Features of a Synthetic Cyclic Peptide Corresponding to the Complete V3 Loop of the ELI HIV-1 Strain in Water

Wim F. Vrankena, Miloš Buděšínskýb, Franky Fanta, Kris Bouleza, Hélène Gras-Massec and Frans A. M. Borremansa

a Biomolecular NMR Unit, Department of Organic Chemistry, University of Gent, B-9000 Gent, Belgium
b Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, 166 10 Prague 6, Czech Republic
c Institut Pasteur de Lille, Chimie des Biomolecules, F-59019 Lille, France


The disulfide bridge closed cyclic peptide corresponding to the whole V3 loop of the envelope protein gp120 of the ELI HIV-1 strain was synthesized and examined by proton 2D NMR spectroscopy in water. Although the peptide is mainly conformationally flexible, a turn appears to be present at an N-terminal glycosylation site, while in the C-terminal half of the peptide the data point toward nascent helical structures. Similar conformational preferences in aqueous solution were observed in other V3 loop peptides, especially for the Ile28-Gly30 tripeptide part.

Keywords: 2D NMR; ELI sequence V3 loop; Conformation in water; gp120; HIV-1.