Stabilising normal and mis-sense variant α-glucosidase

alpha-Glucosidase (EC 3.2.1.3) is a lysosomal enzyme that hydrolyses alpha-1,4- and alpha-1,6-linkages of glycogen to produce free glucose. A deficiency in alpha-glucosidase activity results in glycogen storage disorder type II (GSD II), also called Pompe disease. Here, D-glucose was shown to be a competitive inhibitor of alpha-glucosidase and when added to culture medium at 6.0 g/L increased the production of this protein by CHO-K1 expression cells and stabilised the enzyme activity. D-Glucose also prevented a-glucosidase aggregation/precipitation and increased protein yield in a modified purification scheme. In fibroblast cells, from adult-onset GSD II patients, D-glucose increased the residual level of a-glucosidase activity, suggesting that a structural analogue Of D-glucose may be used for enzyme enhancement therapy. (c) 2006 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.