title: A model peptide with enhanced helicity.
abstract: The sequence of a model monomeric peptide, acetylA(EAAAK)3Aamide was altered to expedite measurement of peptide concentration and to enhance its fractional helical content. Replacement of the N-terminal alanine residue with a tryptophan residue provides a convenient chromophore for measurement of peptide concentration without diminishing the helical content. Replacement of the three lysine residues with arginine residues enhances the helical content without loss of their electrostatic contributions. Increasing the number of EAAAR sequence units in the peptide acetylW(EAAAR)nAamide from three to five indicates that the spectral features anticipated for a completely helical peptide are closely approached.
authors.affiliation: Department of Biochemistry, University of Iowa, Iowa City 52242.
authors.forename: G
authors.initials: G
authors.lastname: Merutka
authors.forename: W
authors.initials: W
authors.lastname: Shalongo
authors.forename: E
authors.initials: E
authors.lastname: Stellwagen
mesh_terms: D000409:Alanine; D000595:Amino Acid Sequence; D002942:Circular Dichroism; D006863:Hydrogen-Ion Concentration; D008969:Molecular Sequence Data; D010455:Peptides / Q000737:chemistry*; D011487:Protein Conformation; D014364:Tryptophan
chemical_list: D010455:Peptides; D014364:Tryptophan; D000409:Alanine