Functional Role of Water in Membranes Updated: A Tribute to Träuble

DISALVO E.A.; PINTO O. A; MARTINI M.F. ; BOUCHET A.M; HALLMANN A; FRIAS M.A.

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2015

he classical view of a cell membrane is as a hydrophobic slab in which only nonpolar solutes can dissolve and permeate. However, water-soluble non-electrolytes such as glycerol, erythritol, urea and others can permeate lipid membranes in the liquid crystalline state. Moreover, recently polar amino acid?s penetration has been explained by means of molecular dynamics in which appearance of water pockets is postulated. According to Träuble (1971), water diffuses across the lipid membranes by occupying holes formed in the lipid matrix due to fluctuations of the acyl chain trans-gauche isomers. These holes, named ?kinks? have the molecular dimension of CH2 vacancies. The condensation of kinks may form aqueous spaces into which molecular species of the size of low molecular weight can dissolve. This molecular view can explain permeability properties considering that water may be distributed along the hydrocarbon chains in the lipid matrix. The purpose of