Methylation of ethanolamine groups in phosphoethanolamines is relevant for L-arginine insertion in lipid membranes

► H bond formation with the lipid NH groups drives Arg adsorption on DMPE in a 2:1 lipid Arg complex. ► Blocking the NH groups of PE by methylation changes the pattern of adsorption to a 1:1 lipid:Arg ratio as in PCs. ► Similar response is obtained when PE groups are in a PC environment.