Computationally designed β‐turn foldamers of γ‐peptides based on 2‐(aminomethyl)cyclohexanecarboxylic acid |
| |
Authors: | Young Kee Kang Byung Jin Byun |
| |
Institution: | Department of Chemistry, Chungbuk National University, Cheongju, Chungbuk 361‐763, Republic of Korea |
| |
Abstract: | The γ‐peptide β‐turn structures have been designed computationally by the combination of chirospecific γ 2 , 3 ‐residues of 2‐(aminomethyl)cyclohexanecarboxylic acid (γAmc6) with a cyclohexyl constraint on the Cα?Cβ bond using density functional methods in water. The chirospecific γAmc6 dipeptide with the (2S,3S)‐(2R,3R) configurations forms a stable turn structure in water, resembling a type II′ turn of α‐peptides, which can be used as a β‐turn motif in β‐hairpins of Ala‐based α‐peptides. The γAmc6 dipeptide with homochiral (2S,3S)‐(2S,3S) configurations but different cyclohexyl puckerings shows the capability to be incorporated into one of two β‐turn motifs of gramicidin S. The overall structure of this gramicidin S analogue is quite similar to the native gramicidin S with the same patterns and geometries of hydrogen bonds. Our calculated results and the recently observed results may imply the wider applicability of chirospecific γ‐peptides with a cyclohexyl constraint on the backbone to form various peptide foldamers. © 2012 Wiley Periodicals, Inc. Biopolymers 97:1018–1025, 2012. |
| |
Keywords: | γ ‐peptides foldamers turn structures hairpin structures density functional calculations |
|
|