Article Gramicidin Ion Channels Isomerism Light Light activation of membrane channels Lipid Bilayers Membrane Proteins Photoinduced changes of membrane elasticity Photolipid Regulation of mechanosensitive channels Scattering, Small Angle X ray crystallography X ray diffraction X-Ray Diffraction cell vacuole chemistry dimer elasticity electric capacitance gramicidin gramicidin A hydrophobicity ion channel isomer isomerism isomerization light lipid bilayer membrane conductance