Glucosyltransferase function

Various strains of oral streptococci produce D-glucosyltransferases which utilize sucrose as a o-glucosyl donor in the production of soluble and insoluble D-glucans. Consequently, it may be expected that some deoxyfluoro derivatives of sucrose function as competitive inhibitors for the dextransu-crases of tooth bacteria, thus preventing decay, or at least may be used as active-site probes for the enzymes. Another aim of these researches is to find non-metabolizable sweeteners. 

The oxime, 34, is glycosylated by a UDPG-thiohydroximate glucosyltransferase, and subsequently sulfonated by sulfotransferase to yield a glucosinolate of the type Thus, aldoximes generated by initial oxygenation of amino acids are found to serve as substrates of a wide variety of plant enzymes that act directly at the hydroximino function. 

Hall D, de Luca Y. 2007. Mesocarp localization of a bi-functional resveratrol/hydro-xycinnamic acid glucosyltransferase of Concord grape (Vitis labrusca). Plant J 49 579-591. 

Figure 3.7 Biosynthesis of cyanogenic glucosides. The biosynthetic pathway of cyanogenic glucosides exemplarily is mentioned for dhurrin. The biosynthesis is performed by the two multi-functional cytochrome P450 enzymes and a UDP-glucosyltransferase. All three enzymes are joined together in a metabolon located in the ER-membrane (according to Nielsen et al., 2008).

Grubb, G.D., Zipp, B.J., Ludwig-Muller, J., Masuno, M.N., Molinski, T.F. and Abel, S. (2004) Arabidopsis glucosyltransferase UGT74B1 functions in glucosinolate biosynthesis and auxinhomeostasis. Plant., 40, 893-908. 

Wamecke, D., Erdmann, R., Fahl, A., Hube, B., Muller, R, Zank, T., Zahringer, U. and Heinz, E. (1999) Cloning and functional expression of UGT genes encoding sterol glucosyltransferases from Saccharomyces cerevisiae, Candida albicans, Pichia pastoris, and Dictyostelium discoideum. J. Biol. Chem., 274,13048-59. 

Wamecke, D.C., Baltrusch, M., Buck, R, Wolter, RP. and Heinz, E. (1997) UDP-glucoseisterol glucosyltransferase cloning and functional expression in Escherichia coli. Plant Mol. Biol, 35, 597-603. 

Hundle BS, O Brien DA, Alberti M, Beyer P and Hearst JE (1992) Functional expression of zeaxanthin glucosyltransferase from Erwinia herbicola and a proposed uridine diphosphate binding site. Proc Natl Acad Sci USA 89 9321-9325... 

---