Enforcing periodic secondary structures in hybrid peptides: a novel hybrid foldamer containing periodic gamma-turn motifs.
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.
Baruah
Pranjal K
PK
Division of Organic Synthesis, Central Material Characterization Division, and Central NMR Facility, National Chemical Laboratory, Dr. Homi Bhabha Road, Pune 411 008, India.
Sreedevi
N K
NK
Gonnade
Rajesh
R
Ravindranathan
Sapna
S
Damodaran
Krishnan
K
Hofmann
Hans-Jörg
HJ
Sanjayan
Gangadhar J
GJ
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
D010455:Peptides