Autor: |
Fisher BF; Department of Chemistry, University of Wisconsin-Madison , Madison, Wisconsin 53706, United States., Gellman SH; Department of Chemistry, University of Wisconsin-Madison , Madison, Wisconsin 53706, United States. |
Jazyk: |
angličtina |
Zdroj: |
Journal of the American Chemical Society [J Am Chem Soc] 2016 Aug 31; Vol. 138 (34), pp. 10766-9. Date of Electronic Publication: 2016 Aug 16. |
DOI: |
10.1021/jacs.6b06177 |
Abstrakt: |
α/γ-Peptide foldamers containing either γ(4)-amino acid residues or ring-constrained γ-amino acid residues have been reported to adopt 12-helical secondary structure in nonpolar solvents and in the solid state. These observations have engendered speculation that the seemingly flexible γ(4) residues have a high intrinsic helical propensity and that residue-based preorganization may not significantly stabilize the 12-helical conformation. However, the prior studies were conducted in environments that favor intramolecular H-bond formation. Here, we use 2D-NMR to compare the ability of γ(4) residues and cyclic γ residues to support 12-helix formation in more challenging environments, methanol and water. Both γ residue types support 12-helical folding in methanol, but only the cyclically constrained γ residues promote helicity in water. These results demonstrate the importance of residue-based preorganization strategies for achieving stable folding among short foldamers in aqueous solution. |
Databáze: |
MEDLINE |
Externí odkaz: |
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