The Levels of Nucleotide-Sugar: Glycoprotein Sialyl- and <i>N</i>-Acetyl-glucosaminyltransferases in Normal and Pathological Human Sera

Abstract

Enzymes which transfer N-acetylneuraminic acid and N-acetylglucosamine from their respective nucleotide-sugars to exogenously added glycoprotein acceptors are present in human sera. The levels of these enzymes have been determined in various pathological sera. Sialyltransferase and N-acetylglucosaminyltransferase levels were increased in a group of patients with various liver diseases. N-Acetylglucosaminyltransferase levels were also increased in a group of patients with a variety of infections. The data support the conclusion that these serum enzymes are derived at least in part from the liver.