Uridine diphosphate-D-glucuronic acid

Feingold, D.S., Neufeld, E.F., and Hassid, W.Z. (1960) The 4-epimerization and decarboxylation of uridine diphosphate d-glucuronic acid by extracts from Phaseolus aureus seedlings. JBiol.Chem. 235 910-913. 

Neufeld, E.F., Feingold, D.S., and Hassid, W.Z. (1958) Enzymatic conversion of uridine diphosphate D-glucuronic acid to uridine diphosphate galacturonic acid, uridine diphosphate xylose, and uridine diphosphate arabinose. JAmer.Chem.Soc. 80 4430 Northcote, D.H. (1985) Control of cell wall formation during growth. In Biochemistry of Plant Cell Walls, edited by C.T. Brett, et al, pp. 177-197. Cambridge University Press, Cambridge. 

Loewus, M.W., and Loewus, F.A., 1974, myo-inositol 1-phosphate synthase inhibition and control of uridine diphosphate-D-glucuronic acid biosynthesis. Plant Physiol. 54 367-371. 

Jl. Jacobson, B, and Davidson, E. A., Biosynthesis of uronic acids by skin enzymes. II. Uridine diphosphate-D-glucuronic acid-5-epimerase. J. Biol. Chem. 237, 638-642 (1962). 

Uridine 5 -(a-D-glucopyranosyluronic acid diphosphate) (UDP-glucuronic acid) has been prepared enzymically from UDP-Glc on a gram scale by using UDP-Glc dehydrogenase.160... 

In a recent note, Dutton and Storey170 have reported the isolation of a thermostable factor necessary to the formation of o-aminophenyl D-glucosiduronic acid in liver homogenates. The compound was said to be a uridine diphosphate derivative of D-glucuronic acid. A series of D-glucuronic acid nucleosides of uracil have recently been synthesized by Goodman171 for study. 

Fig. 4 Formation of uridine diphosphate glucuronic acid (UDP-GA) and its conjugation with clofibric acid. Inversion takes place during conjugation, the a-D-glucuronic acid forming a P-D-glucuronide. At a more alkaline pH, such glu-curonides may undergo intramolecular rearrangement to forms resistant to enzymic hydrolysis by P-glucuronidase.

The enzyme and coenzyme for the above conjugation reactions are uridine diphosphate glucuronyl transferase and uridine-5 -diphospho-a-D-glucuronic acid, respectively.)... 

A. Glucuronidation UDP-glucuronyltransferases (EC 2.4.1.17) The reaction may occur spontaneously with some substrates Phenols, alcohols carboxylic acids amines, amides, sulphonamides, thiols RXH + uridinediphospho-j8-D-glucuronic acid RX-glucoronide + uridine-5 -diphosphate where X is O, N or S (and more rarely C) to give 0-, N- and S-glucuronides. 

The uridine diphosphate ester derivatives in a non-capsulated. Type II pneumococcus and a capsulated. Type III pneumococcus were investigated by Smith, Mills, and Harper." The capsule of the Type III pneumococcus is composed of a polysaccharide having 4-0-( 8-D-glucopyranosyluronic acid)-D-glucose as a repeating unit. n-Glucuronic acid, D-glucose, and L-rhamnose are constituents of the capsular polysaccharide of the Type II pneumococcus. 

Two additional related derivatives of uridine-5-phosphate have recently been reported. Uridine diphosphate acetylglucosamine has been isolated from yeast. (Cabib, E., Leloir, L. F., and Cardini, C. E., J. Biol. Chem. 203, 1055 (1953).) Uridine diphosphate glucuronic acid is stated to be an active metabolite in glu-curonide formation. (Dutton, G. J. and Storey, I. D. E., Biochem. J. 63, xxxvii (1953).)... 

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