Proton Gradient-Induced Water Transport Mediated by Water Wires Inside Narrow Aquapores of Aquafoldamer Molecules

Abstract

Hollow tubular aquapores inside aquafoldamers can be created via the “sticky” end-mediated formation of 1D chiral helical stacks involving same-handed helices, and are capable of aligning H-bonded water molecules in a chain-like fashion. These aquapores uniquely feature a small cavity of ∼2.8 Å in diameter, a size identical to that of the water molecule and also comparable to the narrowest opening in naturally occurring aquaporins measuring ∼3 Å across, and hence allow not only proton transport but also unique proton-gradient-induced water transport across the lipid membranes in the presence of proton gradient.