SOLUTION CONFORMATION OF AN ETB SELECTIVE AGONIST, ET-1[CYS(ACM)(1,15),ALA(3),LEU(7),AIB(11)], IN CD3OH H2O BY H-1-NMR AND MOLECULAR MODELING/

To understand the basic structural requirements for the biological act ivity of endothelin peptides, the solution structure of an ETB selecti ve agonist, ET-1[Cys-(Acm)(1,15), Ala(3),Leu(7),Aib(11)], was investig ated by H-1 NMR spectroscopy and molecular modelling. The structure is characterised by an alpha-helical conformation between residues Ser(5 )-His(16) but is undefined at both the N and C termini. To date, neith er the solution structures of linear modified peptides nor the effects of a methano/water solvent system have been examined for endothelin o r endothelin-like peptides. This structure plays an important role tow ards the design of endothelin receptor selective agonists and antagoni sts. (C) 1998 Federation of European Biochemical Societies.