ENZYME PATTERNS IN TISSUES AND BODY FLUIDS IN MUCOPOLYSACCHARIDOSES

The activity of one of two demonstrable 4-methylumbelliferyl-β-galactosidase (MU-β-galactosidase) activities was decreased in brain, kidney and spleen from patients with mucopolysaccharidosis (MPS) type I and II. Increased activities of β-acetylglucosaminidase, acid phosphatase and β-glucuronidase were found in all or some of the gargoylism tissues analysed, whereas α-mannosidase and α-fucosidase had the same activity as in controls. Studies of total activity, heat inactivation, inhibition by gluconolactone, and substrate specificity showed that the one of the two MU-β-galactosidase activities, that was markedly deficient in all tissues analysed, was not significantly diminished in plasma and urine. In cases of MPS type I, II, III and IV part of the MU-β-galactosidase activity in urine in gel filtration experiments was displaced from a fraction with apparent M.W. 85000 to a larger-molecular fraction. An explanation is discussed of these findings. It is concluded that MPS patients have a deficiency of one of the two demonstrable MU-β-galactosidase activities in many tissues, but urine and plasma cannot be used for diagnosing the defect. © 1969.