Morphology of bile salts micelles and mixed micelles with lipolysis products, from scattering techniques and atomistic simulations
2021
Pabois, Olivia | Ziolek, Robert | Lorenz, Christian | Prévost, Sylvain | Mahmoudi, Najet | Skoda, Maximilian W.A. | Welbourn, Rebecca J.L. | Valero, Margarita | Harvey, Richard | Grundy, Myriam M.-L. | Wilde, Peter | Grillo, Isabelle | Gerelli, Yuri | Dreiss, Cécile | Institut Laue-Langevin (ILL) | King‘s College London | ISIS Neutron and Muon Source (ISIS) ; STFC Rutherford Appleton Laboratory (RAL) ; Science and Technology Facilities Council (STFC)-Science and Technology Facilities Council (STFC) | Universidad de Salamanca [España] = University of Salamanca [Spain] | Universität Wien = University of Vienna | Physiologie, Environnement et Génétique pour l'Animal et les Systèmes d'Elevage [Rennes] (PEGASE) ; Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-INSTITUT AGRO Agrocampus Ouest ; Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro) | Quadram Institute ; Biotechnology and Biological Sciences Research Council (BBSRC) | Polytechnic University of Marche / Università Politecnica delle Marche (UNIVPM) | European Project: 654000
International audience
اظهر المزيد [+] اقل [-]إنجليزي. HypothesesBile salts (BS) are biosurfactants released into the small intestine, which play key and contrasting roles in lipid digestion: they adsorb at interfaces and promote the adsorption of digestive enzymes onto fat droplets, while they also remove lipolysis products from that interface, solubilising them into mixed micelles. Small architectural variations on their chemical structure, specifically their bile acid moiety, are hypothesised to underlie these conflicting functionalities, which should be reflected in different aggregation and solubilisation behaviour.ExperimentsThe micellisation of two BS, sodium taurocholate (NaTC) and sodium taurodeoxycholate (NaTDC), which differ by one hydroxyl group on the bile acid moiety, was assessed by pyrene fluorescence spectroscopy, and the morphology of aggregates formed in the absence and presence of fatty acids (FA) and monoacylglycerols (MAG) – typical lipolysis products – was resolved by small-angle X-ray/neutron scattering (SAXS, SANS) and molecular dynamics simulations. The solubilisation by BS of triacylglycerol-incorporating liposomes – mimicking ingested lipids – was studied by neutron reflectometry and SANS.FindingsOur results demonstrate that BS micelles exhibit an ellipsoidal shape. NaTDC displays a lower critical micellar concentration and forms larger and more spherical aggregates than NaTC. Similar observations were made for BS micelles mixed with FA and MAG. Structural studies with liposomes show that the addition of BS induces their solubilisation into mixed micelles, with NaTDC displaying a higher solubilising capacity.
اظهر المزيد [+] اقل [-]الكلمات المفتاحية الخاصة بالمكنز الزراعي (أجروفوك)
المعلومات البيبليوغرافية
تم تزويد هذا السجل من قبل Institut national de la recherche agronomique