background: sandhoff disease is an autosomal recessive disorder caused by β-hexosaminidase deficiency and accumulation of gm2 ganglioside resulting in progressive motor neuron manifestations and death from respiratory failure and infections in infantiles. pathogenic mutations in hexb gene were observed which leads to enzyme activity reduction and interruption of normal metabolic cycle of gm2 ga...

Hexosaminidase S (HEX S), the residual isozyme found in tissues and body fluids of children with the O variant of GM2 gangliosidosis, was purified from tissues of variant individuals and biochemically and immunochemically characterized. This enzyme has an apparent molecular weight of 103,000 with an isoelectric point of 4.2, is heat labile to the same extent as HEX A, and loses most of its acti...

Exoglycosidases are hydrolases involved in lysosomal degradation of oligosaccharide chains of glycoconjugates (glycoproteins, glycolipids and proteoglycans). In tissues and body fluids, a higher exoglycosidase specific activity is found in N-acetyl-β-hexosaminidase, than β-glucuronidase, α-L-fucosidase, β-galactosidase, α-mannosidase and α-glucosidase. Determination of exoglycosidases (especial...

The separation of N-acetyl-beta-D-hexosaminidase isoenzymes from human tissues is used in the diagnosis and differential diagnosis of GM(2) gangliosidosis, since in type 1 the A isoenzyme is deficient and in type 2 both the A and B isoenzymes are deficient. Peripheral blood leucocytes are commonly used for these investigations, and the present study demonstrates that, in addition to these two i...

Monocyte hydrolases are harmful when secreted inappropriately. In this study we have investigated the levels of one of the hydrolases. beta-hexosaminidase in patients with obstructive jaundice. These patients showed markedly elevated plasma levels, and their monocytes show increased spontaneous secretion and total enzyme content. The plasma enzyme levels correlate with monocyte enzyme content a...

The expression of constitutively active H-RasV12 oncogene has been described to induce proliferative arrest and premature senescence in many cell models. There are a number of studies indicating an association between senescence and lysosomal enzyme alterations, e.g. lysosomal β-galactosidase is the most widely used biomarker to detect senescence in cultured cells and we previously reported tha...

We describe a method for continuous kinetic measurement of hexosaminidase activity, and have applied it to detection of heterozygotes for Tay-Sachs gene. In contrast to existing single-point methods, a ph of 4.5, which is optimal for hexosaminidase activity on the substrate (4-methylumbelliferyl-N-acetyl-beta-d-glucosaminide) is maintained while the increase in fluorescence produced by 4-methyl...