[Properties of membrane-bound sialyltransferase from rana temporaria liver].

It was demonstrated that microsomal membranes from frog liver contain at least two different sialyltransferases involved in the synthesis of alpha 2 leads to 3 and alpha 2 leads to 6 oligosaccharide isomers. Studies on acceptor specificity of the sialyltransferase system with respect to low molecular acceptors revealed its similarity to the mammalian sialyltransferase system. However, sharp distinctions were observed in sialylation of mammalian glycoproteins. It was assumed that that the disaccharide unit of the acceptor oligosaccharide chain is a structural element, which in necessary but not sufficient for glycoprotein recognition by sialyltransferases.