GLYCOSYL TRANSFERASE ACTIVITY IN NORMAL AND SCRAPIE-AFFECTED MOUSE BRAIN

—The conditions required for the optimal activity of several glycosyl transferases were determined in normal and scrapie-affected mouse brain. Particulate preparations were analysed for fucosyl, galactosyl, mannosyl and N-acetyl glucosaminyl transferase activity using endogenous acceptors. Solubilized preparations were analysed for fucosyl, galactosyl and sialyl transferase activity using defined exogenous acceptors. The activity of each of these enzymes was followed at intervals throughout the development of scrapie in the mouse. In the endogenous system no change was found in the fucosyl and mannosyl transferase activities of the scrapie material, but the levels of galactosyl and N-acetyl glucosaminyl transferase began to rise as clinical signs of scrapie developed i.e. at 15–16 weeks post-inoculation. In the exogenous system the levels of galactosyl and fucosyl transferase began to rise in the scrapie material at 11–12 weeks post-inoculation, rising to twice the normal value at 18–20 weeks. Sialyl transferase showed no change in activity.