NMR and CD studies on the conformation of a synthetic peptide containing epitopes of the human immunodeficiency virus 1 transmembrane protein gp41.
CD and nmr characterizations are reported for the 23-mer peptide CMC3, corresponding to residues 577-599 of gp41, the transmembrane glycoprotein of the human immunodeficiency virus 1. Concentration, temperature, and pH dependencies of CD and nmr spectra are indicative of self-association with a consequent stabilization of secondary structural elements in water. The addition to the water solution of small amounts of trifluoroethanol induces a secondary structure, mostly due to the presence of helical elements. The amphipathic character of the helix and the presence of three hydrophobic 4/3 heptad repeats suggest that the peptide could be structured in a symmetric association of helices, such as in a coiled-coil structure. This behavior is discussed in terms of a possible role of this segment in the gp41 envelope oligomerization.
Istituto di Chimica delle Marcromolecole Lab. NMR, Milano, Italy.
R
R
Consonni
R
R
Limiroli
R
R
Longhi
E
E
Manera
G
G
Vecchio
L
L
Ragona
A G
AG
Siccardi
L
L
Zetta
D000595:Amino Acid Sequence; D002942:Circular Dichroism; D000939:Epitopes / Q000737:chemistry*; D015700:HIV Envelope Protein gp41 / Q000737:chemistry* / Q000276:immunology; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D010455:Peptides / Q000138:chemical synthesis / Q000737:chemistry*; D011487:Protein Conformation
D000939:Epitopes; D015700:HIV Envelope Protein gp41; D010455:Peptides