FORMATION OF AN EXTREMELY STABLE POLYALANINE BETA-SHEET MACROMOLECULE

We have designed a 16-mer peptide composed of a stretch of alanine res idues (Ac-KA(14)K-NH2) which is an effective, simple model for the stu dy of beta-sheet formation in the hydrophobic cores of proteins. This peptide adopts an aqueous soluble ''bundling'' macromolecular beta-she et structure, which is extremely stable to a wide range of pHs, temper atures and/or denaturants. Its unusual stability appears to be due to tight hydrophobic packing of the alanine residues in multilayer sheets or micellar forms with the multimeric lysine array being directed out ward at the aqueous environment, allowing aqueous solubility. (C) 1995 Academic Press, Inc.