Accepted name: N-hydroxythioamide S-β-glucosyltransferase
Reaction: (1) UDP-α-D-glucose + (Z)-2-phenyl-1-thioacetohydroximate = UDP + desulfoglucotropeolin
(2) UDP-α-D-glucose + an (E)-ω-(methylsulfanyl)alkyl-thiohydroximate = UDP + an aliphatic desulfoglucosinolate
(3) UDP-α-D-glucose + (E)-2-(1H-indol-3-yl)-1-thioacetohydroximate = UDP + desulfoglucobrassicin
Glossary: an aliphatic desulfoglucosinolate = an ω-(methylsulfanyl)alkylhydroximate S-glucoside
Other name(s): UGT74B1 (gene name); desulfoglucosinolate-uridine diphosphate glucosyltransferase; uridine diphosphoglucose-thiohydroximate glucosyltransferase; thiohydroximate β-D-glucosyltransferase; UDPG:thiohydroximate glucosyltransferase; thiohydroximate S-glucosyltransferase; thiohydroximate glucosyltransferase; UDP-glucose:thiohydroximate S-β-D-glucosyltransferase; UDP-glucose:N-hydroxy-2-phenylethanethioamide S-β-D-glucosyltransferase
Systematic name: UDP-α-D-glucose:N-hydroxy-2-phenylethanethioamide S-β-D-glucosyltransferase
Comments: The enzyme specifically glucosylates the thiohydroximate functional group. It is involved in the biosynthesis of glucosinolates in cruciferous plants, and acts on aliphatic, aromatic, and indolic substrates.
1.  Jain, J.C., Reed, D.W., Groot Wassink, J.W.D. and Underhill, E.W. A radioassay of enzymes catalyzing the glucosylation and sulfation steps of glucosinolate biosynthesis in Brassica species. Anal. Biochem. 178 (1989) 137–140. [PMID: 2524977]
2.  Reed, D.W., Davin, L., Jain, J.C., Deluca, V., Nelson, L. and Underhill, E.W. Purification and properties of UDP-glucose:thiohydroximate glucosyltransferase from Brassica napus L. seedlings. Arch. Biochem. Biophys. 305 (1993) 526–532. [PMID: 8373190]
3.  Marillia, E.F., MacPherson, J.M., Tsang, E.W., Van Audenhove, K., Keller, W.A. and GrootWassink, J.W. Molecular cloning of a Brassica napus thiohydroximate S-glucosyltransferase gene and its expression in Escherichia coli. Physiol. Plant 113 (2001) 176–184. [PMID: 12060294]
4.  Fahey, J.W., Zalcmann, A.T. and Talalay, P. The chemical diversity and distribution of glucosinolates and isothiocyanates among plants. Phytochemistry 56 (2001) 5–51. [PMID: 11198818]
5.  Grubb, C.D., Zipp, B.J., Ludwig-Muller, J., Masuno, M.N., Molinski, T.F. and Abel, S. Arabidopsis glucosyltransferase UGT74B1 functions in glucosinolate biosynthesis and auxin homeostasis. Plant J. 40 (2004) 893–908. [PMID: 15584955]
[EC created 1992, modified 2006, modified 2018]

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