title: Aromatic interactions with naphthylalanine in a β-hairpin peptide.
abstract: Stable peptides have been explored as epitope mimics for protein-protein and protein-nucleic acid interactions; however, presentation of a regular structure is critical. Aromatic interactions are ubiquitous and are competent at stabilizing a β-hairpin fold. The greatest stabilization has been reported from pairs of tryptophan side chains. Naphthylalanine residues are often used as tryptophan replacements, but it is not clear if 1-naphthylalanine or 2-naphthylalanine is adequate at replicating the geometry and stability observed with tryptophan aromatic interactions. Herein, a 12-residue peptide has been constructed with laterally disposed aromatic amino acids. A direct comparison is made between tryptophan and other bicyclic, unnatural amino acids. Significant stabilization is gained from all bicyclic amino acids; however, geometric analysis shows that only 1-naphthylalanine adopts a similar edge to face geometry as tryptophan, whereas the 2-naphthylalanine appears most similar to a substituted phenylalanine.
authors: Calvin College, Chemistry and Biochemistry, Grand Rapids, Michigan, USA.
authors: Daniel
authors: D
authors: Meyer
authors: Caleb
authors: C
authors: Mutschler
authors: Ian
authors: I
authors: Robertson
authors: Alexandra
authors: A
authors: Batt
authors: Chad
authors: C
authors: Tatko
mesh_terms: D000409:Alanine / Q000031:analogs & derivatives / Q000737:chemistry; D024322:Amino Acids, Aromatic / Q000138:chemical synthesis* / Q000737:chemistry; D003871:Dermatan Sulfate / Q000138:chemical synthesis* / Q000737:chemistry; D009281:Naphthalenes / Q000737:chemistry; D010455:Peptides / Q000138:chemical synthesis* / Q000737:chemistry; D010649:Phenylalanine / Q000737:chemistry; D014364:Tryptophan / Q000737:chemistry
chemical_list: D024322:Amino Acids, Aromatic; D009281:Naphthalenes; D010455:Peptides; D003871:Dermatan Sulfate; D010649:Phenylalanine; C059031:1-naphthylalanine; D014364:Tryptophan; D000409:Alanine; C513002:2-naphthylalanine