title: NMR study of five N-terminal peptide fragments of the vasoactive intestinal peptide: crucial role of aromatic residues.
abstract: Five peptides related to the N-terminal sequence of the vasoactive intestinal peptide (VIP) have been synthesized. Two-dimensional nuclear magnetic resonance (2D-NMR) experiments (i.e., correlated spectroscopy [COSY]) and low temperature coefficient measurements for particular NH chemical shifts suggest the presence of hydrogen bondings in both VIP (1-7, and VIP (1-11) fragments. Nuclear Over-hauser enhancement spectroscopy (NOESY) show that aromatic interactions stabilize a preferred conformation. The crucial role of the first histidine residue, which is a determinant for the biological activity, is explained by specific interactions with the aromatic protons of Phe6 and Tyr10.
authors.affiliation: Institut de Chimie Pharmaceutique. Université de Lille II, France.
authors.forename: J F
authors.initials: JF
authors.lastname: Goossens
authors.forename: P
authors.initials: P
authors.lastname: Cotelle
authors.forename: P
authors.initials: P
authors.lastname: Chavatte
authors.forename: J P
authors.initials: JP
authors.lastname: Hénichart
mesh_terms: D000577:Amides / Q000737:chemistry; D006860:Hydrogen Bonding; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D010446:Peptide Fragments / Q000138:chemical synthesis / Q000737:chemistry*; D010649:Phenylalanine / Q000737:chemistry; D017510:Protein Folding; D017433:Protein Structure, Secondary; D011522:Protons; D013696:Temperature; D014443:Tyrosine / Q000737:chemistry; D014660:Vasoactive Intestinal Peptide / Q000737:chemistry*
chemical_list: D000577:Amides; D010446:Peptide Fragments; D011522:Protons; D014660:Vasoactive Intestinal Peptide; D014443:Tyrosine; D010649:Phenylalanine