Antimicrobial peptides could help address the problem of bacterial drug resistance if their mechanisms for disrupting bacterial membranes are better understood. New techniques are needed to help characterize peptide-lipid systems and understand the mechanisms by which peptides disrupt membranes. We introduce distance perturbations for 2D correlation spectroscopy (2D-COS) to aid in characterizing peptide-lipid systems. The 2D-COS order of positions method links spectral changes to the positions of functional groups in peptide-bilayer systems. As a first step in our exploration, we study the quantum density functional theory normal modes of lipids to model the order of positions for lipid bilayers. The Z coordinate and radial coordinate orders of positions are explored to determine if they can be mapped back to distance-related metrics, such as RMSD. Overall, we are creating a framework to describe the structure and structural distributions from a 2D-COS point of view, which helps describe systems like the peptide-lipid system in terms of an ensemble of important conformations.
Allsopp et al. (Sun,) studied this question.