glycoprotein 4-β-galactosyltransferase

gly·co·pro·tein 4-β-ga·lac·to·syl·trans·fer·ase (gli″ko-proґtēn gə-lak″to-səl-transґfər-ās) an enzyme of the transferase class that catalyzes the attachment of galactose moieties derived from UDP-galactose to N-acetylglucosamine residues of glycoproteins. The enzyme is present in many tissues; in secreting mammary gland cells it complexes with α-lactalbumin to form lactose synthase. In EC nomenclature, called β-N-acetylglucosaminyl-glycopeptide β-1,4-galactosyltransferase.