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| =='''Introduction to α-lactalbumin and its Function''' ==
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| α-lactalbumin is a 123 residue ~14kD whey protein that is only found in milk and the mammary gland and is involved in production of lactose. α-lactalbumin is produced in the endoplasmic reticulum. When it makes it way to the Golgi it encounters galactosyltransferase and other substrates necessary for lactose synthesis.<ref>Neville MC.. 2009. Introduction: alpha-lactalbumin, a multifunctional protein that specifies lactose synthesis in the Golgi. '' J Mammary Gland Biol Neoplasia.'' (3):211-2</ref> The complex is made up of galactosyltransferase, α-lactalbumin, nucleotide substrate, and metal ion cofactors. α-lactalbumin is a modifier protein of the lactose synthetase complex.<ref name="ii">Cawthern KM, Permyakov E, Berliner LJ. 1996. Membrane-bound states of α-lactalbumin:Implications for the protein stability and conformation. Protein Science. 5: 1394-1405</ref> Lactose synthetase catalyzes the final step in the biosynthesis of lactose in the mammary gland by the reaction:
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| UDP-D-galactose + D-glucose -- lactose + UDP.<ref> Keith Brew, Thomas C. Vanaman and Robert L. Hill. 1967. The Role Of α-lactalbumin and The A Protein in Lactose Sythetase: A Unique Mechanism For the Control of A Biological Reaction. ''Biochemistry PNAS'' 491-497</ref>
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| α-lactalbumin is found in human milk of mothers who have been lactating for at least one month. It is the most abundant protein providing an osmotic force that drives water from the mothers blood vessels into her mammary glands as well as the formation of lactose as part of the lactose synthesis molecule. It provides much of the nutrients that an infant needs ~15% of the protein and 16% of the nitrogen content.<ref>Jackson JG, Janszenb DB, Lonnerdalc B, Liena EL, Pramuka KP, Kuhlman CF. 2004. A multinational study of α-lactalbumin concentrations in human milk. Journal of Nutritional Biochemistry. 15: 517-521.</ref> α-lactalbumin is highly similar to the c-type lysozymes sharing primary, secondary and tertiary structures. It is supposed that α-lactalbumin has evolved from c-type lysozyme, however the function of α-lactalbumin is distinct from c-type lysozyme.<ref name="ii"> </ref>
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| {{STRUCTURE_1a4v | PDB=1a4v | SCENE= }} | |
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| == '''Secondary and Tertiary Structure of α-lactalbumin'''== | | == '''Secondary and Tertiary Structure of α-lactalbumin'''== |
