Critical Role of Molecular Packing in Lo Phase Membrane Solubilization

Membrane solubilization induced by Triton X-100 (TX-100) was investigated. Different membrane compositions and phase states were studied along the detergent titration. Expected profiles obtained but new information is provided. The fluorescence of nitrobenzoxadiazole (NBD)-labeled lipids indicates that liquid-ordered (Lo)/liquid-disordered (Ld) coexistence barely unaffected at sub-solubilizing concentrations highlights vesicle-to-micelle transition. Moreover, location NBD group in bilayer emphasizes a detergent–membrane interaction case insoluble Lo membrane. It has also been shown molecular packing loosens presence TX-100, regardless profile. Motivated studies on GPMVs, less ordered membranes considered order to improve effect extent solubilization. Membranes composed SM Chol an equimolar ratio doped with different amounts PC studied. more absence detergent, likely it be solubilized. Furthermore, contrast what observed for exhibiting Lo/Ld coexistence, very small decrease radically modifies These results have implications reliability TX-100 insolubility as method detect domains.