Document Type
Article
Publication Date
6-17-2019
Publisher
American Chemical Society
Abstract
In this study, we provide a quantitative description of the adsorption of water-soluble N-substituted glycine oligomers (peptoids) to supported lipid bilayers that mimic mammalian plasma membranes. We prepared a small array of systematically varied peptoid sequences ranging in length from 3 to 15 residues. Using the nonlinear optical method second harmonic generation (SHG), we directly monitored adsorption of aqueous solutions of 3- and 15-residue peptoids to phospholipid membranes of varying physical phase, cholesterol content, and head group charge in physiologically relevant pH buffer conditions without the use of extrinsic labels. Equilibrium binding constants and relative surface coverages of adsorbed peptoids were determined from fits to the Langmuir model. Three- and 15-residue peptoids did not interact with cholesterol-containing lipids or charged lipids in the same manner, suggesting that a peptoid’s adsorption mechanism changes with sequence length. In a comparison of four three-residue peptoids, we observed a correlation between equilibrium binding constants and calculated log D7.4 values. Cationic charge modulated surface coverage. Principles governing how peptoid sequence and membrane composition alter peptoid–lipid interactions may be extended to predict physiological effects of peptoids used as therapeutics or as coatings in medical devices.
Recommended Citation
Landry, M. R., Rangel, J. L., Dao, V. P., MacKenzie, M. A., Gutierrez, F. L., Dowell, K. M., Calkins, A. L., Fuller, A. A., & Stokes, G. Y. (2019). Length and Charge of Water-Soluble Peptoids Impact Binding to Phospholipid Membranes. The Journal of Physical Chemistry B, 123(27), 5822–5831. https://doi.org/10.1021/acs.jpcb.9b04641
Comments
This is an open access article published under an ACS AuthorChoice License, which permits copying and redistribution of the article or any adaptations for non-commercial purposes.