Uridine diphosphate (UDP)-glucose dehydrogenase (UDPGDH) represents a key enzyme required for synthesis of glycosaminoglycans (GAGs) and for detoxification of toxins, drugs, and endogenous substances such as steroids, heme pigments, and thyroxine via glucuronidation. UDPGDH is a four-electron transferring NAD- oxidoreductase that oxidizes UDP-Glc to UDP-GlcA through two separate but linked reactions. The product of the first half-reaction remains covalently bound to the enzyme and is the substrate for the second half-reaction. The active UDPGDH (the form best characterized is from bovine liver) is an apparent homohexamer of 52- kilodalton (kDa) subunits functioning as a trimer of dimers. The primary product of UDPGDH action, UDP-GlcA, is critical to the synthesis of GAGs and to the function of proteoglycans. UDP-GlcA is converted to UDP-Xyl, which is required for initiation of the GAG chain on proteoglycan cores. Furthermore, UDP-GlcA is required for polymerization of the GAGs, hyaluronan (HA), heparan sulfate (HS), chondroitin sulfate (CS), and dermatan sulfate (DS).
KeywordsDermatan Sulfate Bovine Liver Glucose Dehydrogenase Uridine Diphosphate Catalytic Cysteine
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