title: Residue requirements for helical folding in short alpha/beta-peptides: crystallographic characterization of the 11-helix in an optimized sequence.
abstract: Design of functional foldamers requires knowledge of the conformational propensities of constituent residues. Here, we explore the effects of variations in both alpha-amino acid and beta-amino acid substitution on alpha/beta-peptide helicity. We also report the first X-ray crystal structure of a helical alpha/beta-peptide. We conclude that a certain amount of conformational preorganization in alpha/beta-peptides (via the inclusion of constrained beta-amino acids or alpha,alpha-disubstituted alpha-amino acids) is needed to promote helical folding; acyclic beta-amino acids and beta-branched alpha-amino acids are tolerated to only a limited extent.
authors.affiliation: Department of Chemistry, University of Wisconsin, Madison, Wisconsin 53706, USA.
authors.forename: Margaret A
authors.initials: MA
authors.lastname: Schmitt
authors.forename: Soo Hyuk
authors.initials: SH
authors.lastname: Choi
authors.forename: Ilia A
authors.initials: IA
authors.lastname: Guzei
authors.forename: Samuel H
authors.initials: SH
authors.lastname: Gellman
mesh_terms: D002240:Carbohydrate Sequence; D003461:Crystallography; D018360:Crystallography, X-Ray; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010455:Peptides / Q000737:chemistry*; D017510:Protein Folding; D017433:Protein Structure, Secondary
chemical_list: D010455:Peptides