0-Glucuronidase

After exhaustive hydrolysis with bovine liver 3-glucuronidase. Trace -<0.01% administered dose. 

D-Saccharic acid 1,4-lactone (SAL 5-10 mM), a selective inhibitor of/3-glucuronidase [29], is often included in UGT reactions for improving yield. As /3-glucuronidases and UGTs have different optimal pH ranges, use of SAL in preparative-scale reactions may be avoided. 

Zenser, T.V., Lakshmi, V.M. and Davis, B.B. (1999) Human and Escherichia coli /3-glucuronidase hydrolysis of glucuronide conjugates of benzidine and 4-aminobiphenyl, and their hydroxy metabolites. Drug Metabolism and Disposition The Biological Fate of Chemicals, 27, 1064—1067. 

Kushinsky, S. and Chen, V.L. (1967) The inhibition of/3-glucuronidase from bovine liver by 1,4-saccharolactone. Comparative Biochemistry and Physiology, 20, 535—542. 

N-Hydroxy arylamines readily form glucuronide conjugates, but in contrast to the N-hydroxy arylamides, these are N-glucuronides which are unreactive and stable at neutral pH. The N-glucuronides are readily transported to the lumens of the urinary bladder and intestine where they can be hydrolyzed to the free N-hydroxy arylamines by mildly acidic urine or by intestinal bacterial 3-glucuronidases (13,14). Non-enzymatic activation of N-hydroxy arylamines can occur in an acidic environment by protonation (15,16) of the N-hydroxy group (VIII) as well as by air oxidation (reviewed in 17) to a nitrosoarene (IX). 

Kikuchi, H., Y. Suzuki, and Y. Hashimoto. 1981. Increase of (3-glucuronidase activity in the serum of rats administered organophosphate and carbamate insecticides. Jour. Toxicol. Sci. 6 27-35. 

The protocol consisted of preconditioning with methanol (1 mL) followed by water (1 mL). Urine samples (3 mL) were deconjugated by treatment with /3-glucuronidase and arylsulfatase (10 jt/L and 200 fig/fiL) in 0.1M sodium acetate (pH 5.5) and then loaded onto conditioned cartridges. After washing with water (1 mL) and methanoksodium acetate (3 mL, 4 6, pH 5.5), the PAH metabolites were eluted with dichloromethane (3 mL). The eluate was spiked with dodecane (used... 

Since then it has been established that emulsin is a mixture of enzymes comprising in addition to /3-glucosidase28 the enzymes a-galactosidase, a-mannosidase, /3-glucuronidase and /3-(N-acetyl)-glucosaminidase. Concerning the process of purification of the Rohferment and the mode of differentiation of the constituent enzymes of emulsin, the most informa-... 

Jain, S., Drendel, W., Chen, Z.-W., Mathews, F., Sly, W., and Grubb, J. (1996). Structure of human /3-glucuronidase reveals candidate lysosomal targeting and active-site motifs. 

Serum (3-glucuronidase activity was increased in a dose-related manner when disulfoton was given intraperitoneally to rats (Kikuchi et al. 1981). In the same study, this effect was not observed in mice, rabbits, or guinea pigs. This enzyme appears to be a useful biomarker of hepatic function in rats exposed to disulfoton, but may not be a useful biomarker in humans. 

The (3-glucuronidase activity of human blood has been studied by Fishman and co-workers.26 The range in 230 normals was found to be from 41 to 1285 units per 100 ml. of serum. In the diseased subjects studied, the minimum values tended to be higher and the maximum values were up to 2340 units. 

The (3-glucuronidase levels in normal healthy individuals are rather constant. Differences in glucuroic acid metabolism were observed which undoubtedly were connected in some way with the enzyme activity of the blood. 

Phenol red glucuronide was determined after either HC1 or 3-glucuronidase hydrolysis. The presence of the glucuronide was confirmed by thin layer chromatography in three systems (J3). 

M. C. Gehrmann, M. Opper, H. H. Sedlacek, K. Bosslet, J. Czech, Biochemical Properties of Recombinant Human /3-Glucuronidase Synthetized in Baby Hamster Kidney Cells , Biochem. J. 1994, 301, 821 - 828. 

J. W. Owens, P. Stahl, Purification and Characterization of Rat Liver Microsomal /3-Glucuronidase , Biochim. Biophys. Acta 1976, 438, 474 - 486. 

D. J. Smith, M. L. Appleton, J. R. Carlson, G. S. Yost, Identification of /3-Glucuronidase-Resistant Diastereomeric Glucuronides of 3-Hydroxy-3-methyloxindole Formed During 3-Methylindole Metabolism in Goats , Drug Metab. Dispos. 1996, 24, 119 - 125. 

P. H. J. Houba, R. G. G. Leenders, E. Boven, J. W. Scheeren, H. M. Pinedo, H. J. Hais-ma, Characterization of Novel Anthracycbne Prodrugs Activated by Human /3-Glucuronidase for Use in Antibody-Directed Enzyme Prodrug Therapy , Biochem. Pharmacol. 

T. V. Zenser, V. M. Lakshmi, B. B. Davis, Human and Escherichia coli /3-Glucuronidase Hydrolysis of Glucuronide Conjugates of Benzidine and 4-Aminobiphenyl, and Their Hydroxy Metabolites , Drug Metab. Dispos. 1999, 27, 1064 - 1077. 

Decreased lysozyme, acid phosphatase, and /3-glucuronidase activity in alveolar macrophages (appears to be linearly related to dose up to 1 ppm)... 

Exposure of animals to ozone lowers their resistance to bacterial infection of the limgs ( ). Ozone exposure also causes changes in the properties of material that can be lavaged from the lungs there is inactivation of the enzymes acid phosphatase, 3-glucuronidase and lysozyme, and there is a tendency for these enzymes to have been released from the alveolar macrophage cells ( ). vivo inactivation of lung lysozyme has... 

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