Molecular basis for nanoscopic membrane curvature generation from quantum mechanical models and synthetic transporter sequences.

摘要: We investigate the physical origin of peptide-induced membrane curvature by contrasting differences between H-bonding interactions prototypical cationic amino acids, arginine (Arg) and lysine (Lys), with phosphate groups phospholipid heads using quantum mechanical (QM) calculations a minimum model test results via synthetic oxaorbornene-based transporter sequences without geometric constraints polypeptide backbones. QM suggest that although individual Lys can in principle coordinate two phosphates, they are not able to do so at small inter-Lys distances drastic energetic penalties. In contrast, Arg phosphates down less than 5 A, where guanidinium stack “face face”. agreement these observations, poly-Lys cannot generate nanoscale positive necessary for inducing negative Gaussian curvature, contrast poly-Arg. Also consistent calculations, polyguanidine-oxanorbornene homopolymers (PGO...