The recent studies on the interaction of surfactants and fatty acids with l
ipids are inspired by the want of knowledge from several research fields of
highest activity: identification of membrane rafts; membrane protein cryst
allization; formation of non-lamellar phases in membranes; membrane fusion.
Detailed phase diagrams for lipid-surfactant and lipid-fatty acid mixtures
, obtained in the last few years, reveal complicated mesomorphic and polymo
rphic behavior, including miscibility gaps and compound formation. Surfacta
nt-induced non-lamellar to lamellar transitions in lipids and specific temp
erature-driven bilayer-micelle transitions represent extensions of the gene
ral three-stage model of membrane solubilization. Further research is requi
red to construct phase diagrams as to delineate the principles of lipid-sur
factant and lipid-fatty acid interactions for the variety of membrane lipid
classes. (C) 2001 Elsevier Science Ltd. All rights reserved.