N-sulphoglucosamine sulphohydrolase is an

enzyme Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products. A ...

that in humans is encoded by the ''SGSH''

gene In biology, the word gene (from , ; "...Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a ba ...

Clinical significance

A number sign (#) is used with this entry because the phenotype is caused by mutation in the gene encoding

N-sulfoglucosamine sulfohydrolase In enzymology, a N-sulfoglucosamine sulfohydrolase () is an enzyme that catalyzes the chemical reaction :N-sulfo-D-glucosamine + H2O \rightleftharpoons D-glucosamine + sulfate Thus, the two substrates of this enzyme are N-sulfo-D-glucosamine an ...

(SGSH; MIM 605270). The

Sanfilippo syndrome Sanfilippo syndrome, also known as mucopolysaccharidosis type III (MPS III), is a rare autosomal recessive lysosomal storage disease that primarily affects the brain and spinal cord. It is caused by a buildup of large sugar molecules called glyc ...

, or mucopolysaccharidosis III, is a

lysosomal storage disease Lysosomal storage diseases (LSDs; ) are a group of over 70 rare inherited metabolic disorders that result from defects in lysosomal function. Lysosomes are sacs of enzymes within cells that digest large molecules and pass the fragments on to other ...

due to impaired degradation of

heparan sulfate Heparan sulfate (HS) is a linear polysaccharide found in all animal tissues. It occurs as a proteoglycan (HSPG, i.e. Heparan Sulfate ProteoGlycan) in which two or three HS chains are attached in close proximity to cell surface or extracellular ma ...

. MPS III includes 4 types, each due to the deficiency of a different enzyme: heparan N-sulfatase (type A); alpha-N-acetylglucosaminidase (type B; MIM 252920); acetyl CoA:alpha-glucosaminide acetyltransferase (type C; MIM 252930); and N-acetylglucosamine 6-sulfatase (type D; MIM 252940). The Sanfilippo syndrome is characterized by severe central nervous system degeneration, but only mild somatic disease. Onset of clinical features usually occurs between 2 and 6 years; severe neurologic degeneration occurs in most patients between 6 and 10 years of age, and death occurs typically during the second or third decade of life. Type A has been reported to be the most severe, with earlier onset and rapid progression of symptoms and shorter survival.

Clinical significance

References

Further reading