March 12, 2018
Journal Article

Peptoid backbone flexibilility dictates its interaction with water and surfaces: A molecular dynamics investigation

Abstract

Peptoids are peptide-mimetic biopolymers that are easy-to-synthesize and adaptable for use in drugs, chemical scaffolds, and coatings. However, there is insufficient information about their structural preferences and interactions with the environment in various applications. We conducted a study to understand the fundamental differences between peptides and peptoids using molecular dynamics simulations with semi-empirical (PM6) and empirical (AMBER) potentials, in conjunction with metadynamics enhanced sampling. From studies of single molecules in water and on surfaces, we found that sarcosine (model peptoid) is much more flexible than alanine (model peptide) in different environments. However, the sarcosine and alanine interact similarly with a hydrophobic or a hydrophilic. Finally, this study highlights the conformational landscape of peptoids and the dominant interactions that drive peptoids towards these conformations. ACKNOWLEDGMENT:MD simulations and manuscript preparation were supported by the MS3 (Materials Synthesis and Simulation Across Scales) Initiative at Pacific Northwest National Laboratory (PNNL), a multi-program national laboratory operated by Battelle for the U.S. Department of Energy. CJM was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences Division of Chemical Sciences, Geosciences, and Biosciences. MDB was supported by the US Department of Energy, Office of Basic Energy Sciences, Biomolecular Materials Program at PNNL. Computing resources were generously allocated by University of Washington's IT department and PNNL's Institutional Computing program. The authors greatly acknowledge conversations with Dr. Kayla Sprenger, Josh Smith, and Dr. Yeneneh Yimer.

Revised: May 18, 2018 | Published: March 12, 2018

Citation

Prakash A., M.D. Baer, C.J. Mundy, and W.J. Pfaendtner. 2018. Peptoid backbone flexibilility dictates its interaction with water and surfaces: A molecular dynamics investigation. Biomacromolecules 19, no. 3:1006-1015. PNNL-SA-132333. doi:10.1021/acs.biomac.7b01813