Biomaterial Database

The monomeric casein composition of different size bovine casein micelles. 1978

B Ekstrand, and M Larsson-Raźnikiewicz

The fractionation by size of casein micelles from bovine skim milk was performed by chromatography on controlled-pore glass granules (CPG-10/3000). Acid precipitation of the fractionated proteins in combination with polyacrylamide gel electrophoresis gave no indication for monomeric caseins in the whey fractions. A factor besides low temperature appears necessary for the dissociation of, for example, beta-casein from casein micelles. The casein composition was studied by DEAE-cellulose chromatography. In bulk skim milk the alphas-, beta- and kappa-caseins were shown to occur in the following relative amounts: 52, 33 and 15%, respectively. The distribution varies with the size of the micelle. In large and medium size micelles the alphas1-casein content is almost constant; beta-casein and kappa-casein appear to be complementary so that the kappa-casein content increases with the decrease in the size of the micelle. In small micelles the relative beta-casein content is about 50%, alphas1-casein is only about 33%. We suggest that beta-casein plays a special role as initiator of micelle formation, and that alphas1-casein stabilizes the structure of the larger micelles.

UI	MeSH Term	Description	Entries
D008823	Micelles	Particles consisting of aggregates of molecules held loosely together by secondary bonds. The surface of micelles are usually comprised of amphiphatic compounds that are oriented in a way that minimizes the energy of interaction between the micelle and its environment. Liquids that contain large numbers of suspended micelles are referred to as EMULSIONS.	Micelle
D008892	Milk	The off-white liquid secreted by the mammary glands of humans and other mammals. It contains proteins, sugar, lipids, vitamins, and minerals.	Cow Milk,Cow's Milk,Milk, Cow,Milk, Cow's
D008970	Molecular Weight	The sum of the weight of all the atoms in a molecule.	Molecular Weights,Weight, Molecular,Weights, Molecular
D002364	Caseins	A mixture of related phosphoproteins occurring in milk and cheese. The group is characterized as one of the most nutritive milk proteins, containing all of the common amino acids and rich in the essential ones.	alpha-Casein,gamma-Casein,AD beta-Casein,Acetylated, Dephosphorylated beta-Casein,Casein,Casein A,K-Casein,Sodium Caseinate,alpha(S1)-Casein,alpha(S1)-Casein A,alpha(S1)-Casein B,alpha(S1)-Casein C,alpha(S2)-Casein,alpha-Caseins,beta-Casein,beta-Caseins,epsilon-Casein,gamma-Caseins,kappa-Casein,kappa-Caseins,AD beta Casein,Caseinate, Sodium,K Casein,alpha Casein,alpha Caseins,beta Casein,beta Caseins,beta-Casein Acetylated, Dephosphorylated,beta-Casein, AD,epsilon Casein,gamma Casein,gamma Caseins,kappa Casein,kappa Caseins
D002417	Cattle	Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.	Beef Cow,Bos grunniens,Bos indicus,Bos indicus Cattle,Bos taurus,Cow,Cow, Domestic,Dairy Cow,Holstein Cow,Indicine Cattle,Taurine Cattle,Taurus Cattle,Yak,Zebu,Beef Cows,Bos indicus Cattles,Cattle, Bos indicus,Cattle, Indicine,Cattle, Taurine,Cattle, Taurus,Cattles, Bos indicus,Cattles, Indicine,Cattles, Taurine,Cattles, Taurus,Cow, Beef,Cow, Dairy,Cow, Holstein,Cows,Dairy Cows,Domestic Cow,Domestic Cows,Indicine Cattles,Taurine Cattles,Taurus Cattles,Yaks,Zebus
D003102	Colloids	Two-phase systems in which one is uniformly dispersed in another as particles small enough so they cannot be filtered or will not settle out. The dispersing or continuous phase or medium envelops the particles of the discontinuous phase. All three states of matter can form colloids among each other.	Hydrocolloids,Colloid,Hydrocolloid
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D046911	Macromolecular Substances	Compounds and molecular complexes that consist of very large numbers of atoms and are generally over 500 kDa in size. In biological systems macromolecular substances usually can be visualized using ELECTRON MICROSCOPY and are distinguished from ORGANELLES by the lack of a membrane structure.	Macromolecular Complexes,Macromolecular Compounds,Macromolecular Compounds and Complexes,Complexes, Macromolecular,Compounds, Macromolecular,Substances, Macromolecular