A technique for the enzymatic diagnosis of glycogen storage disease on very small tissue specimens

Glucose-containing oligosaccharides in the urine of patients with glycogen storage disease type II and type III

Patients with glycogen storage disease type II and type III were recently found to excrete increased amounts of a glucose-containing tetrasaccharide DGlcp(alpha1 leads to 6)DGlcp(alpha1 leads to 4)DGlcp(alpha1 leads to 4)DGlc [Lennartson, G., Lundblad, A., Sjöblad, S., Svensson, S. and Ockerman, P.A. (1976) Biomed. Mass Spectrom. 3, 51--54]. In addition to this tetrasaccharide, urine from these patients also contains larger oligosaccharides containing only glucose. From urine of patients with glycogen storage disease type II and type III, three and four oligosaccharides respectively have been isolated. Structural studies including sugar analyses, methylation analyses, partial acid hydrolysis and optical rotation revealed that three compounds were present in the urine of both patients. Their proposed structures or partial structures are as follows: DGlcp(alpha1--6)DGlcp(alpha1--6)DGlcp(alpha1--4)DGlcp(alpha1--4)DGlcp(alpha1--4)DGlc, DGlcp(alpha1--4)DGlcp(alpha1--6)DGlcp(alpha1--6)DGlcp(alpha1--4)DGlcp(alpha1--4)DGlc, and DGlcp(alpha1--6)DGlcp(alpha1--4)DGlcp(alpha1--4)DGlcp(alpha1--4)DGlcp(alpha1--6)DGlcp(alpha1--4)DGlcp(alpha1--4)DGlc. A fourth compound has been partially characterized as a branched heptasaccharide with four (1 leads to 4) linkages and two (1 lead to 6) linkages. Glycogen is possibly the origin of these compounds. However, the number of (1 leads to 6) linkages is higher than expected and may indicate a shorter distance between branches in glycogen than has been generally assumed.

Gargoylism: hydrolysis of beta-galactosides and tissure accumulation of galactose- and mannose-containing compounds

The sugars present in hydrolyzed extracts of human liver and brain were analyzed by gasliquid chromatography after conversion to their alditol acetates. The samples analyzed were obtained from control subjects, patients with gargoylism, and patients with a few other kinds of storage disorders. Accumulation of galactose was demonstrated in the liver and the brain of two patients with gargoylism, and in the liver samples, high levels of mannose were found too. We also studied the hydrolysis of a number of galactosides by homogenates from different tissues in the control subjects and in the patients. Separation methods and kinetic studies demonstrated the presence in normal human tissues of two different beta-galactosidases, which we call enzyme A and enzyme B, respectively. Enzyme A hydrolyzed all the beta-galactosides tested. Enzyme B hydrolyzed the synthetic substrates tested (4-methylumbelliferyl-, p-nitrophenyl-, o-nitrophenyl-, and phenyl-beta-galactoside) but not the natural substrates tested (ceramide-beta-galactoside, ceramide lactoside, transferrin glycopeptide, and keratan sulfate). Enzyme B also exerted beta-glucosidase activity. In various tissues from patients with gargoylism, deficiency of beta-galactosidase A could be demonstrated. It is suggested that the high level of galactose found in the hydrolyzed extracts of tissues from gargoylism patients is due to storage of galactose-rich glycosaminoglycans and glycopeptides, and that this storage is a result of the deficiency of beta-galactosidase A. The high level of mannose in the liver from gargoylism patients seems to indicate storage of glycopeptide, adding a new group of substances to those known to be stored in gargoylism.