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许多含伯胺、仲胺和叔胺的的化学物质与葡糖醛酸结合能形成N-葡糖醛酸代谢物。大约30余种UDP-葡糖醛酸转移酶已经被纯化,或克隆与表达,其中一些可以催化伯胺和叔胺的N-葡醛酸结合反应。UGT1的基因突变,致使一些物种不能形成季铵葡醛酸结合物。研究UGT同工酶对致癌芳杂环胺的代谢产物的催化活性,对于了解这些化合物的致癌危险性具有很大的意义。致癌的芳杂环胺通过代谢成为N-羟化物后,产生基因毒性,UDP-葡糖醛酸转移酶和母体胺结合或与N-羟化代谢物结合形成N-羟化胺类的N-葡醛酸苷,使之代谢失活,或产生稳定的结合物后转移到靶相组织(膀胱),进一步变成有活性的代谢物。
Many chemicals containing primary, secondary, and tertiary amines can combine with glucuronic acid to form N-glucuronate metabolites. About 30 UDP-glucuronosyltransferases have been purified, or cloned and expressed, some of which catalyze the N-glucuronidation of primary and tertiary amines. UGT1 gene mutations, resulting in some species can not form quaternary ammonium gluconate conjugates. Studying the catalytic activities of UGT isoenzymes on the metabolites of carcinogenic aromatic heterocyclic amines is of great significance for understanding the carcinogenic risk of these compounds. The oncogenic aromatic heterocyclic amines produce, via metabolism to N-hydroxylates, genotoxicity, binding of UDP-glucuronosyltransferases to the parent amine or to N-hydroxylated metabolites to form N- Glucuronide, the metabolism of inactivation, or to produce a stable conjugate after the transfer to target tissues (bladder), further into an active metabolite.