Characterization of substance P-membrane interaction by transferred nuclear Overhauser effect

Substance P, one of the mammalian tachykinins is known to interact strongly with lipid bilayers and this interaction may play a role in the receptor-p eptide recognition process. The conformation of substance P bound to vesicl es consisting of perdeuterated phosphatidylcholine has been investigated by means of two-dimensional transferred nuclear Overhauser (trNOE) spectrosco py. Nuclear magnetic resonance data analysis resulted in a unique conformat ional family characterized by a well-defined conformation of the last seven C-terminal amino acids, which consists of a sequence of nonstandard turns following each other in a helix-like manner. The absence of short- or mediu m-range trNOE in the N-terminal part indicates its structural flexibility. (C) 2000 John Wiley & Sons, Inc.