Nanotube width difference in assemblies consisting of E22L vs E22V

A residue substitution from Leu (E22L) to Val (E22V), essentially a single methyl's difference, in the amyloid beta-42 16-22 truncation of KLVFFAE resulted in nanotubes of drastically different widths. While E22L nanotubes registered at 38 nm, E22V nanotubes registered at 278 nm. Peptides were assembled at 1.3 mM in 40% acetonitrile and 0.1 % trifluoroacetic acid.