Structure and orientation of a bilayer-bound model tripeptide: a proton NMR study

The conformation and orientation of a model peptide, A-F-A-O-tert-butyl, was studied in sonicated unilamellar phosphatidylcholine (PC) vesicles by proton NMR. Intramolecular nuclear Overhauser enhancements (NOEs) were measured for the tripeptide in free solution and with PC vesicles. The peptide has no stable tertiary structure in free solution but adopts a structure in the presence of PC vesicles. Restrained molecular dynamics using NOE constraints were used to deduce a preferred structure for the bound tripeptide