Glucuronic acid, conjugation with

Although UGTs catalyze only glucuronic acid conjugation, CYPs catalyze a variety of oxidative reactions. Oxidative biotransformations include aromatic and side chain hydroxylation, N-, O-, S-dealkylation, N-oxidation, sulfoxidation, N-hydroxylation, deamination, dehalogenation and desulfation. The majority of these reactions require the formation of radical species this is usually the rate-determining step for the reactivity process [28]. Hence, reactivity contributions are computed for CYPs, but a different computation is performed with the UGT enzyme (as described in Section 12.4.2). 

C2. Childs, B., Sudbury, J. B., and Migeon, C. J., Glucuronic acid conjugation by patients with familial nonhemolytic jaundice and their relatives. Pediatrics 23, 903-913 (1959). 

Certain thiols may be conjugated directly through the sulfur atom (Fig. 4.55). Glucuronic acid conjugated directly to carbon atoms has been reported such as with the drug phenylbutazone. 

The mouse has less sulfotransferase activity with respect to the a-hydroxytamoxifen, but more glucuronosyl transferase activity. The resulting glucuronic acid conjugation is a clear detoxication pathway, as a stable metabolite is formed, which can be readily eliminated. Hence, the mouse is much less susceptible, and although some tamoxifen is covalently bound to liver DNA, no hepatic tumors have been detected. 

This, together with the glucuronic acid conjugate, is eliminated predominantly in the urine and feces... 

The first, unequivocal evidence for N-hydroxylation of an aromatic amine in vivo was obtained with 2-(acetamido)fluorene, which was detected in urine as its N-hydroxy derivative almost entirely in the form of a D-glucuronic acid conjugate (that could be cleaved by /3-d-glucosiduronase), to which structure 133 was assigned.362,383 Activation of chemical carcinogens (that are not themselves reactive, but are... 

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