title: Glycosyltransferases with endogenous acceptor activity in plasma membranes isolated from rat liver.
abstract: Plasma membrane fractions from rat liver exhibited glycosyltransferase activity with endogenous membrane-associated acceptors and either UDP-galactose, UDPglucose, UDP-N-acetylglucosamine, or GDPmannose donors. Of these, incorporation into non-lipid acceptors was most active with UDP-galactose and only with UDPgalactose and UDPmannose was there incorporation into endogenous lipid acceptors. CMP-N-acetylneuraminic acid was inactive as a donor with the isolated plasma membranes. In order to demonstrate transferase activity, low concentrations of substrate sugar nucleotides and short incubation times were used as well as sulfhydryl protectants and a phosphatase inhibitor (NaF) in the reaction mixtures. The findings support the concept of surface localization of at least a galactosyl transferase in cells of rat liver.
mesh_terms: D000818:Animals; D002462:Cell Membrane / Q000201:enzymology; D005700:Galactosyltransferases / Q000378:metabolism; D005964:Glucosyltransferases / Q000378:metabolism; D006602:Hexosyltransferases / Q000302:isolation & purification / Q000378:metabolism*; D008099:Liver / Q000201:enzymology*; D008297:Male; D008364:Mannosyltransferases / Q000378:metabolism; D051381:Rats; D012799:Sialyltransferases / Q000378:metabolism; D014537:Uridine Diphosphate N-Acetylglucosamine
chemical_list: D014537:Uridine Diphosphate N-Acetylglucosamine; D005700:Galactosyltransferases; D005964:Glucosyltransferases; D006602:Hexosyltransferases; D008364:Mannosyltransferases; D012799:Sialyltransferases