title: Enforcing periodic secondary structures in hybrid peptides: a novel hybrid foldamer containing periodic gamma-turn motifs.
abstract: This note describes the design, synthesis, and conformational studies of a novel hybrid foldamer that adopts a definite compact, three-dimensional structure determined by a combined effect of the special conformational properties of the foldamer constituents. The striking feature of this de novo designed foldamer is its ability to display periodic gamma-turn conformations stabilized by intramolecular hydrogen bonds. Conformational investigations by single-crystal X-ray studies, solution-state NMR, and ab initio MO theory at the HF/6-31G* level strongly support the prevalence of gamma-turn motifs in both the di- and tetrapeptide foldamers, which are presumably stabilized by bifurcated hydrogen bonds in the solid and solution states. The strategy disclosed herein for the construction of hybrid foldamers with periodic gamma-turn motifs has the potential to significantly augment the conformational space available for foldamer design with diverse backbone structures and conformations.
authors.affiliation: Division of Organic Synthesis, Central Material Characterization Division, and Central NMR Facility, National Chemical Laboratory, Dr. Homi Bhabha Road, Pune 411 008, India.
authors.forename: Pranjal K
authors.initials: PK
authors.lastname: Baruah
authors.forename: N K
authors.initials: NK
authors.lastname: Sreedevi
authors.forename: Rajesh
authors.initials: R
authors.lastname: Gonnade
authors.forename: Sapna
authors.initials: S
authors.lastname: Ravindranathan
authors.forename: Krishnan
authors.initials: K
authors.lastname: Damodaran
authors.forename: Hans-Jörg
authors.initials: HJ
authors.lastname: Hofmann
authors.forename: Gangadhar J
authors.initials: GJ
authors.lastname: Sanjayan
mesh_terms: D020816:Amino Acid Motifs; D018360:Crystallography, X-Ray; D006860:Hydrogen Bonding; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D008958:Models, Molecular; D010455:Peptides / Q000737:chemistry*; D017510:Protein Folding; D017433:Protein Structure, Secondary; D012680:Sensitivity and Specificity
chemical_list: D010455:Peptides