Effects of Guanidinium-Phosphate Hydrogen Bonding on the Membrane-Bound Structure and Activity of an Arginine-Rich Membrane Peptide from Solid-State NMR Spectroscopy

Barreling through: Guanidinium–phosphate hydrogen bonding significantly affects the structure and activity of the antimicrobial peptide PG‐1. Solid‐state NMR data show that a mutant of PG‐1, having dimethylated Arg residues, adopts an in‐plane orientation, interfacial location, and fast uniaxial motion around the membrane normal (see scheme). The less active mutant thus disrupts the membrane by in‐plane diffusion, in contrast to the more active wild‐type PG‐1, which forms immobile transmembrane β‐barrels to cause toroidal‐pore membrane defects.