Deciphering the role of interfacial properties of milk fat globule membrane in its interaction with the surrounding proteins, the casein micelles
| Autor: | Obeid, Sameh, Guyomarc'h, Fanny, David Briand, Elisabeth, Riaublanc, Alain, Lopez, Christelle, Gaucheron, Frederic |
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| Přispěvatelé: | Science et Technologie du Lait et de l'Oeuf (STLO), Institut National de la Recherche Agronomique (INRA)-AGROCAMPUS OUEST, Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), Institut National de la Recherche Agronomique (INRA), Centre National Interprofessionnel de l'Economie Laitière (CNIEL), 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) |
| Jazyk: | angličtina |
| Rok vydání: | 2018 |
| Předmět: |
milk fat globules
sphingomyeline matière grasse du lait propriété interfacial interaction physicochimique micelle de caséine globule gras du lait sphingomyelin fat globule microscopie à force atomique milk protein protéine du lait [SDV.IDA]Life Sciences [q-bio]/Food engineering globule lipidique lipids (amino acids peptides and proteins) [SDV.AEN]Life Sciences [q-bio]/Food and Nutrition |
| Zdroj: | IDF World Dairy Summit 2018 IDF World Dairy Summit 2018, Oct 2018, Daejeon, North Korea. 2018 |
| Popis: | The interactions between the milk fat globule membrane (MFGM) and proteins (e.g. enzymes, caseins, whey proteins) are poorly known despite their importance in many interfacial mechanisms occurring at the surface of milk fat globules. The MFGM exhibits polar lipids lateral heterogeneities: the zwitterionic milk sphingomyelin (MSM) molecules form domains in gel-phase or in liquid-ordered (Lo) phase in the presence of cholesterol, that are surrounded by a fluid matrix of phospholipids in the liquid-disordered (Ld) phase composed of the unsaturated phosphatidylcholine (PC) and the anionic phosphatidylserine (PS) and phosphatidylinositol (PI) [1,2].AimThe aim of this study was to determine how the phase state and head-group charge of MFGM polar lipids drive interactions with the negatively charged casein micelles, as the major milk protein assembly.MethodsHydrated supported lipid bilayers with various compositions were prepared, including MFGM polar lipid extract, MSM, MSM/cholesterol, MSM/DOPC, DOPC/PS/PI. Real-time atomic force microscopy (AFM) imaging in liquid was performed before and after injection of casein micelles. Zeta-potential and Langmuir isotherms of the different polar lipids offered complementary information.ResultsThe interaction of casein micelles with milk polar lipids is hindered by the high lateral packing density of MSM domains in gel and Lo phases and by the negative charge of PI and PS, certainly due to electrostatic repulsions. But the casein micelles did adsorb onto the Ld phases of DOPC and of MSM above its phase transition temperature (T>Tm=34.3°C[3]), probably as a result of large inter-molecular distances.ConclusionThe absence of interaction between casein micelles and the complex MFGM polar lipids is due to the MSM-rich ordered domains and to the presence of anionic phospholipids in the Ld phase. These results open perspectives for the design of liposomes and emulsions with variable capacity for protein adsorption by the modulation of phase state and charge of the interfacial polar lipids.References: [1] Et-Thakafy et al., Food Chem., 2017, 220, 352–361 [2] Murthy et al., BBA-Biomembranes, 2016, 1858, 2181-2190[3] Murthy et al., BBA-Biomembranes, 2015, 1848, 2308-2316 |
| Databáze: | OpenAIRE |
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