GLUCURONIDES (pair glucuronic acids) — glycosides of beta D-glucuronic acid; are formed in the course of desintoxication of medicinal, toxic, alien compounds and some metabolites in a human body and animals.
Glucuronides are formed in an organism by transfer of the rest glucuronic to - you about uridinediphosphate - alpha D-glucuronic to - you are (UDF-glyukuronat) on substance acceptor, e.g. alcohol: Udfglyukuronat + R — IT -> R — About • (C 6 O 6 H 9 ) + UDF. The rest glucuronic to - you can join also oxygen of carboxyl and gidroksilaminny groups (O-glucuronides), to a nitrogen atom (N-glyukurovidy) or are gray (S-glucuronides). Reaction is catalyzed by enzymes of a liver — Udfglyukuronat - glyukuroniltransferazam (not specific to an acceptor; KF 2. 4. 1. 17).
Important fiziol, the role of formation of glucuronides is connected with the fact that this reaction is one of the main conjugation tests leading to neutralization and allocation medicinal and toxics and some metabolites alien substances (products of metabolism of intestinal microflora, medicine, chemical environmental pollution) concern To them as many normal metabolites (bilirubin, steroids, thyroxine, etc.), and. At the heart of a pathogeny hemolitic disease of newborns (see) insufficiency of the glyukuroniltransferaza catalyzing G.'s education of bilirubin lies, i.e. that form of bilirubin, edge it is brought out of an organism; as a result of this enzymopathies bilirubin collects in blood and fabrics. The pathogeny of symptoms of pechenochnokletochny insufficiency and a hepatic coma is connected with poisoning of an organism with toxics owing to disturbance of the mechanism of reactions of neutralization in a liver, in particular reactions of formation of glucuronides (see. Liver ).
See also Hexuronic acids .
Bibliography: Kochetkov N. K., etc. Chemistry of carbohydrates, page 299, etc., M., 1967; Park D. B. Biochemistry of alien connections, the lane with English, page 93, M., 1973.
A. Ya. Nikolaev.