Identification of a Gal beta 1 goes to 3GlcNAc alpha 2 goes to 3 sialyltransferase in rat liver.
Rat liver Golgi was found to contain a sialyltransferase activity which would convert lacto-N-tetraose (Gal beta 1 goes to 3GlcNAc beta 1 goes to 3Gal beta 1 goes to 4Glc) to LS-tetrasaccharide a (NeuAc alpha 2 goes to 3Gal beta 1 goes to 3GlcNAc beta 1 goes to 3Gal beta 1 goes to 4Glc). The enzyme has been partially purified by affinity chromatography on CDP-hexanolamine agarose. Of the glycoprotein substrates examined, it utilizes the Gal beta 1 goes to 3GlcNAc sequence found on the asparagine-linked oligosaccharides of prothrombin as its preferred acceptor substrate, and thus has been tentatively designated a Gal beta 1 goes to 3GlcNAc alpha 2 goes to 3 sialyltransferase. The partially purified enzyme has an acceptor specificity distinct from other purified mammalian sialyltransferases which synthesize the NeuAc alpha 2 goes to 3Gal beta 1 goes to 3 GalNAc and NeuAc alpha 2 goes to 6 GalNAc sequences common to oligosaccharides O-linked to threonine or serine and the NeuAc alpha 2 goes to 6Gal beta 1 goes to 4GlcNAc sequence found on oligosaccharides N-linked to asparagine.
D000818:Animals; D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D006056:Golgi Apparatus / Q000201:enzymology; D008099:Liver / Q000201:enzymology*; D051381:Rats; D012799:Sialyltransferases / Q000302:isolation & purification / Q000378:metabolism; D013379:Substrate Specificity
D012799:Sialyltransferases; C034256:beta-galactosyl(1-3)N-acetylglucosaminide alpha(2-3)-sialyltransferase