the galactosyltransferase of lactose synthase ( udpgalactose : d-glucose 4 beta-galactosyl-transferase , ec 2.4.1.22 ) was also present in secretory vesicle preparations , alphas1- and beta-caseins , alpha-lactalbumin , and beta-lactoglobulin , the major secretory proteins of differentiated mammary epithelial cells , were identified as constituents of vesicle-rich fractions from bovine mammary gland .
C0002287
alpha-lactalbumin
C0929301
mammary gland