[Analysis of sialyltransferase activity in human serum (author's transl)].

The activity of sialyltransferase in human serum was determined by a radiochemical assay with desialylized fetuin as acceptor. The precision of this method proved to be low. The effect of storage, temperature, concentration of hydrogen ions and other substances was investigated. As at least 5 pH-optima were found, multiple forms of sialyltransferase may well exist in serum.