Effect of dehydrocholic acid conjugated with a hydrocarbon on a lipid bilayer composed of 1,2-dioleoyl-sn-glycero-3-phosphocholine

Publication date: Available online 10 May 2019Source: Colloids and Surfaces B: BiointerfacesAuthor(s): Keita Hayashi, Kazutoshi Morimoto, Toshiyuki Kamei, Eiko Mieda, Sosaku Ichikawa, Takashi Kuroiwa, Sakiko Fujita, Hidemi Nakamura, Hiroshi UmakoshiAbstractThe effects of bile acids, dehydrocholic acid (DHA) and DHA conjugated with a hydrocarbon (6-aminohexanoate; 6A-DHA) were evaluated using a lipid bilayer composed of 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC). DOPC formed a homogenous thin membrane in presence or absence of theDHA, while 20 mol% 6A-DHA induced phase separation on the DOPC thin membrane. It was observed formation of a stomatocyte-like liposomes when these membranes were suspended in a buffer at pH 9. Generally,liposome formation can be prevented by some bile acids. It was found that DHA and 6A-DHA did not disrupt liposome formation, while it perturbed the liposomal membrane, resulting in increased local-fluidity due to the bent structure of DHA and 6A-DHA. DHA and 6A-DHA showed completely different effects on the hydrophobicity of the boundary surface of DOPC liposome membranes. The steroidal backbone of DHA was found to prevent the insertion of water molecules into the liposomal membrane, whereas 6A-DHA did not show the same behavior which was attributed to its conjugated hydrocarbon.Graphical abstract

Source: Colloids and Surfaces B: Biointerfaces - May 17, 2019 Category: Biochemistry Source Type: research