N-linked carbohydrate moieties

N-linked carbohydrate moieties at Asn297 of the Ch2 domain and a protein A binding site between Ch2 and Ch3 [9, 10],... 

Schachter H, Brockhausen I (1992) The biosynthesis of Serine/Threonine-N-Acetylgalac-tosamine-Linked carbohydrate moieties. In Allen HJ, Kisalius EC (eds) Glycoconjugates composition, structure and function Marcel Dekker, New York, p 263... 

Schachter, H., and Brockhausen, I., 1992, The biosynthesis of serine (threonine)-N-acetylgalac-tosamine-linked carbohydrate moieties, in Glycoconjugates—Composition, Structure and Function (H. J. Allen and E. C. Kisailus, eds.), Dekker, New York, pp. 263-404. 

Immunoglobulins are glycoproteins. The carbohydrate moiety is attached to the heavy chain (usually the Ch2 domain) via an N-linked glycosidic bond. Removal of the carbohydrate group has no effect upon antigen binding but does affect various antibody effector functions and alters its serum half-life. 

Like as2-casein, /e-casein has two disulfide bonds which can form cross-links with /3-lactoglobulin. The N-terminal two-thirds of the molecule is hydrophobic and contains the two disulfide bonds. The C-termi-nal end is hydrophilic, polar, and charged. It varies in the number of attached carbohydrate moieties and has only one phosphate group. These characteristics make /c-casein ideal for the surface of casein micelles, where it is most often found. It is not susceptible to calcium ion binding, as the other caseins are, and when present on the surface of micelles, it protects the other caseins from calcium (McMahon and Brown 1984A Swaisgood 1982). 

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