Iduronate 2-sulfatase (EC 3.1.6.13; systematic name
L-iduronate-2-sulfate 2-sulfohydrolase) is a
sulfatase
In biochemistry, sulfatases are a class of enzymes of the esterase class that catalyze the hydrolysis of sulfate esters into an Alcohol (chemistry), alcohol and a bisulfate:
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Text may refer to:
Written word
* Text (literary theory)
In literary theory, a text is any object that can be "read", whether this object is a work of literature, a street sign, an arrangement of buildings on a city block, or styles of clothi ...
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These may be found on a rang ...
enzyme
An enzyme () is a protein that acts as a biological catalyst by accelerating chemical reactions. The molecules upon which enzymes may act are called substrate (chemistry), substrates, and the enzyme converts the substrates into different mol ...
associated with
Hunter syndrome
Hunter syndrome, or mucopolysaccharidosis type II (MPS II), is a rare genetic disorder, inherited lysosomal storage disease in which large sugar molecules called glycosaminoglycans (or GAGs or mucopolysaccharides) build up in body tissues. Hunte ...
.
It catalyses hydrolysis of the 2-sulfate groups of the
L-iduronate 2-sulfate units of dermatan sulfate, heparan sulfate and heparin.
Function
Iduronate 2-sulfatase is required for the lysosomal degradation of
heparan sulfate
Heparan sulfate (HS) is a linear polysaccharide found in all animal tissues. It occurs in 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 ...
and
dermatan sulfate
Dermatan sulfate is a glycosaminoglycan (formerly called a mucopolysaccharide) found mostly in skin, but also in blood vessels, heart valves, tendons, and lungs.
It is also referred to as chondroitin sulfate B, although it is no longer classifi ...
. Mutations in this X-chromosome gene that result in enzymatic deficiency lead to the sex-linked
mucopolysaccharidosis
Mucopolysaccharidoses are a group of metabolic disorders caused by the absence or malfunctioning of lysosomal enzymes needed to break down molecules called glycosaminoglycans (GAGs). These long chains of sugar carbohydrates occur within the cel ...
type II, also known as Hunter syndrome. At least 174 disease-causing mutations in this gene have been discovered.
Iduronate-2-sulfatase has a strong
sequence homology
Sequence homology is the homology (biology), biological homology between DNA sequence, DNA, RNA sequence, RNA, or Protein primary structure, protein sequences, defined in terms of shared ancestry in the evolutionary history of life. Two segments ...
with human
arylsulfatases A, B, and C, and human
glucosamine-6-sulfatase. A splice variant of this gene has been described.
See also
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Idursulfase
References
Further reading
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External links
GeneReviews/NIH/NCBI/UW entry on Mucopolysaccharidosis Type II
EC 3.1.6
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