InterPro domain: IPR002213

UDP glycosyltransferases (UGT) are a superfamily of enzymes that catalyses the addition of the glycosyl group from a UTP-sugar to a small hydrophobic molecule. This family currently consist of:

• Mammalian UDP-glucuronosyl transferases ( 2.4.1.17 ) (UDPGT) [ 1 ]. A large family of membrane-bound microsomal enzymes which catalyse the transfer of glucuronic acid to a wide variety of exogenous and endogenous lipophilic substrates. These enzymes are of major importance in the detoxification and subsequent elimination of xenobiotics such as drugs and carcinogens. These enzymes are also involved in cancer progression and drug resistance [ 2 ].
• A large number of putative UDPGT from Caenorhabditis elegans.
• Mammalian 2-hydroxyacylsphingosine 1-beta-galactosyltransferase [ 3 ] ( 2.4.1.47 ) (also known as UDP-galactose-ceramide galactosyltransferase). This enzyme catalyses the transfer of galactose to ceramide, a key enzymatic step in the biosynthesis of galactocerebrosides, which are abundant sphingolipids of the myelin membrane of the central nervous system and peripheral nervous system.
• Plants flavonol O(3)-glucosyltransferase ( 2.4.1.91 ), an enzyme that catalyses the transfer of glucose from UDP-glucose to a flavanol. This reaction is essential and one of the last steps in anthocyanin pigment biosynthesis. Gallate 1-beta-glucosyltransferase ( 2.4.1.136 ), a glucosyltransferase that catalyses the formation of 1-O-galloyl-beta-D-glucose, the first committed step of hydrolyzable tannins (HTs) biosynthesis [ 4 ].
• (R)-mandelonitrile beta-glucosyltransferase from almond, which is involved in the biosynthesis of the cyanogenic glycoside (R)-prunasin (stereo-selective), a precursor of (R)-amygdalin which at high concentrations is associated with bitterness in kernels of almond [ 5 ].
• Baculoviruses ecdysteroid UDP-glucosyltransferase ( 2.4.1 ) [ 6 ] (egt). This enzyme catalyses the transfer of glucose from UDP-glucose to ectysteroids which are insect molting hormones. The expression of egt in the insect host interferes with the normal insect development by blocking the molting process.
• Prokaryotic zeaxanthin glucosyltransferase ( 2.4.1 ) (gene crtX), an enzyme involved in carotenoid biosynthesis and that catalyses the glycosylation reaction which converts zeaxanthin to zeaxanthin-beta-diglucoside; Enterobactin C-glucosyltransferase iroB which catalyses the successive monoglucosylation, diglucosylation and triglucosylation of enterobactin decreasing the membrane affinity of Enterobactin and increasing the iron acquisition rate [ 7 , 8 ].
• Streptomyces macrolide glycosyltransferases ( 2.4.1 ) [ 9 ]. These enzymes specifically inactivate macrolide antibiotics via 2'-O-glycosylation using UDP-glucose.

1. The UDP glucuronosyltransferase gene superfamily: suggested nomenclature based on evolutionary divergence. DNA Cell Biol. 10, 487-94
2. Emerging roles for UDP-glucuronosyltransferases in drug resistance and cancer progression. Br. J. Cancer 122, 1277-1287
3. Ceramide UDPgalactosyltransferase from myelinating rat brain: purification, cloning, and expression. Proc. Natl. Acad. Sci. U.S.A. 90, 10265-9
4. Two UGT84 Family Glycosyltransferases Catalyze a Critical Reaction of Hydrolyzable Tannin Biosynthesis in Pomegranate (Punica granatum). PLoS One 11, e0156319
5. A seed coat cyanohydrin glucosyltransferase is associated with bitterness in almond (Prunus dulcis) kernels. Funct Plant Biol 35, 236-246
6. A baculovirus blocks insect molting by producing ecdysteroid UDP-glucosyl transferase. Science 245, 1110-2
7. The C-glycosyltransferase IroB from pathogenic Escherichia coli: identification of residues required for efficient catalysis. Biochim Biophys Acta 1844, 1619-30
8. Enzymatic tailoring of enterobactin alters membrane partitioning and iron acquisition. ACS Chem Biol 1, 29-32
9. Characterization of a Streptomyces antibioticus gene cluster encoding a glycosyltransferase involved in oleandomycin inactivation. Gene 134, 139-40