Biosynthesis of Drug Glucuronide Metabolites in the Budding Yeast Saccharomyces cerevisiae

Abstract

Glucuronidation is one of the most common pathways in mammals for detoxification and elimination of hydrophobic xenobiotic compounds, including many drugs. Metabolites, however, can form active or toxic compounds, such as acyl glucuronides, and their safety assessment is often needed. The absence of efficient means for in vitro synthesis of correct glucuronide metabolites frequently limits such toxicological analyses. To overcome this hurdle we have developed a new approach, the essence of which is a coexpression system containing a human, or another mammalian UDP-glucuronosyltransferases (UGTs), as well as UDP-glucose-6-dehydrogenase (UGDH), within the budding yeast, Saccharomyces cerevisiae. The system was first tested using resting yeast cells coexpressing UGDH and human UGT1A6, 7-hydroxycoumarin as the substrate, in a reaction medium containing 8% glucose, serving as a source of UDP-glucuronic acid. Glucuronides were readily formed and recovered from the medium. Subsequently, by selecting suitable mammalian UGT enzyme for the coexpression system we could obtain the desired glucuronides of various compounds, including molecules with multiple conjugation sites and acyl glucuronides of several carboxylic acid containing drugs, namely, mefenamic acid, flufenamic acid, and zomepirac. In conclusion, a new and flexible yeast system with mammalian UGTs has been developed that exhibits a capacity for efficient production of various glucuronides, including acyl glucuronides.

In vivo absorption and metabolism of leptosperin and methyl syringate, abundantly present in manuka honey

“…MSYR‐GA was prepared by incubation of MSYR with resting yeast cells coexpressing uridine diphosphate (UDP)‐glucose dehydrogenase (UGDH) and human UDP‐glucuronosyltransferases (UGTs) according to the published method with some modifications . Among the 15 strains examined (UGT1A1, 1A3, 1A4, 1A5, 1A6, 1A7, 1A8, 1A9, 1A10, 2A1, 2B4, 2B7, 2B10, 2B15, and 2B17), yeast cells that expressed UGT1A7 generated MSYR‐GA most effectively (Supporting Information Table 1).…”

Flavonoid metabolism: the interaction of metabolites and gut microbiota

“…To estimate the physiological activity of flavonoid metabolites, the use of authentic pure molecules is critical. Recently, Ikushiro et al established a system for biosynthesis of various phase II conjugates in budding yeast culture, making it possible to obtain isolated conjugates on a massive scale [57]. These novel methods to produce various individual metabolites would be the key to further investigation.…”

Synthesis of steroid bisglucuronide and sulfate glucuronide reference materials: Unearthing neglected treasures of steroid metabolism

“…As an enzymatic method of glucuronylation, the E. coli glucuronylsynthase is mechanistically distinct from the UGT-promoted biosynthesis of steroid glucuronides [52], [53] but shares several key attributes, including mild and single-step conjugation. One notable feature of the glucuronylsynthase approach is the ability to adjust reaction scale using standard laboratory methods [42].…”