Premium
Helix promotion in polypeptides by polyols
Author(s) -
Bello Jake
Publication year - 1993
Publication title -
biopolymers
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.556
H-Index - 125
eISSN - 1097-0282
pISSN - 0006-3525
DOI - 10.1002/bip.360330315
Subject(s) - melittin , chemistry , glycerol , helix (gastropod) , sucrose , peptide , stereochemistry , crystallography , organic chemistry , biochemistry , ecology , snail , biology
Abstract The helix content of [ L ‐Lys(Me 3 )] n · ClO 4 , and [ L ‐Lys(Me 3 ) 50 , L ‐Ala 50 ] n · ClO 4 in water is markedly increased by the presence of sucrose and glycerol. For [ L ‐Lys(Me 3 )] n · ClO 4 the ellipticity at 222 nm changes from +2 × 10 3 deg cm 2 dmole −1 in water to −44 × 10 3 in 50% glycerol. Sucrose does not promote helix formation in melittin at pH 7.2, but glycerol does. At pH 5.5 sucrose and, more so, glycerol, induce helix in melittin. Glycerol induces some helix in methylated melittin, but less than in melittin. The results are discussed in relation to excluded volume effects, Δ G of transfer of peptide and hydrophobic groups from water to mixed solvents, electrostatic effects, and preferential hydration. © 1993 John Wiley & Sons, Inc.