This view shows enzymes only for those organisms listed below, in the list of taxa known to possess the pathway. If an enzyme name is shown in bold, there is experimental evidence for this enzymatic activity.
|Superclasses:||Degradation/Utilization/Assimilation → Carbohydrates Degradation → Polysaccharides Degradation → Glycans Degradation|
|Degradation/Utilization/Assimilation → Carbohydrates Degradation → Polysaccharides Degradation → Glycosaminoglycan Degradation|
|Degradation/Utilization/Assimilation → Polymeric Compounds Degradation → Polysaccharides Degradation → Glycans Degradation|
|Degradation/Utilization/Assimilation → Polymeric Compounds Degradation → Polysaccharides Degradation → Glycosaminoglycan Degradation|
Some taxa known to possess this pathway include : Homo sapiens
Expected Taxonomic Range: Metazoa
Chondroitin sulfate is a sulfated glycosaminoglycan composed of alternating units of N-acetyl-β-D-galactosamine(β1,3)β-D-glucuronate linked to each other by a β(1,4) linkage. It is usually found attached to proteins as part of a proteoglycan.Chondroitin sulfate is a major component of connective tissue matrix (such as skin and cartilage), but is also found on cell surface and basement membranes and in intracellular granules of certain cells. Functions in matrix locations are mainly structural, while functions in membranes are mainly as receptors.
Degradation of chondroitin sulfate within the animal is part of many processes. For example, such degradation increases the permeability of connective tissues and decreases the viscosity of body fluids. Although some of the enzymes involved are circulated in the plasma, the general process of chondroitin sulfate degradation generally takes place in the lysosome. Chondroitin degradation promoted by bacterial of other enzymes is also involved in bacterial pathogenesis and the spread of toxins and venoms. The process starts with hydrolysis of the large chondroitin sulfate polymer to small segments, which is catalyzed by a family of enzymes known as hyaluronidases. One of these enzymes, encoded by the HYAL4, is a dedicated chondroitinase. Others, encoded by HYAL1 and SPAM1, have higher affinity towards hyaluronan, but also degrade chondroitin sulfate at a lower rate.
Depending on the enzyme, the large chondroitin sulfate polymers are degraded into smaller oligosaccharides, often hexa- and tetrasaccharides, and eventually into disaccharides. Since the sugars in the chondroitin sulfate molecule are sulfated, dedicated enzymes, such as the arylsulfatase B and N-acetylgalactosamine-6-sulfatase remove the sulfate groups, resulting in regular disaccharide molecules that can be degraded further into basic building blocks.
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