Peptoids with aliphatic sidechains as helical structures without hydrogen bonds and collagen/ inverse-collagen type structures

Abstract

Aliphatic homo-polypeptoids of NAla, NVal, NIle and NLeu both in the presence and absence of protecting groups adopt helical structures without hydrogen bonds with Φ, Ψ values of ~ 0, ± 90° with trans amide bonds. These structures are stabilized by carbonyl-carbonyl interactions and characterized by ~ 3.16 residues per turn with a pitch of ~ 6.13 Å. It has been shown that like polyvaline and polyleucine peptides, polypeptoids can also be exploited for the construction of potential surfactant like molecules by incorporating charged amino acid residues at the N terminal. A single-handed template with Φ, Ψ values of ~ 0, 90 ̊ can be attained by incorporating L-leu or L-val at the C-terminal of poly-NIle. Analysis of the simulation results in water as a function of time reveals that the opening of helical structures without hydrogen bonds takes place at sub-picosecond time scale starting from the N-terminal. This leads to the formation of collagen or inverse-collagen type structures (Φ, Ψ ~ -60, 145 ̊ and 60, -145 ̊ respectively) stabilized by interactions of water molecules with the backbone carbonyl groups.

12 Figures and Tables

Cite this paper

@inproceedings{Nandel2011PeptoidsWA, title={Peptoids with aliphatic sidechains as helical structures without hydrogen bonds and collagen/ inverse-collagen type structures}, author={Fateh Singh Nandel and Avneet Saini}, year={2011} }