Cloning And Functional Study Of Key Enzymes In The Natural Product Glucosides’ Biosynthesis Pathway From Ornithogalum Caudatum

Sugar moieties, as part of many bioactive natural products, have important effects on the physiological activity, selectivity, and pharmacological properties of these products. Glycosylation is a prominent modification reaction and is often the last step in the biosynthesis of natural compounds. Glycosyltransferases are key enzymes in glycosylation.UDP-sugars are important substrate for glycosyltransferase to form glycosylation in the biosynthesis of natural compound. There are lots of UDP-sugars in living beings. Plants and microorganism possess a sophisticated sugar biosynhthetic machinery comprising families of nucleotide sugar interconversion enzymes.Our study is focused on biosynthesis of sugar moieties of natural compounds. We have cloned 17 genes from Ornithogalum caudatum in the UDP-sugars (UDP-glucose, UDP-galactose, UDP-xylose, UDP-arabinose, UDP-apiose, UDP-rhamnose, UDP-glucuronic acid, UDP-galacturonic acid) biosynthesis pathway concluding OcUXS1-6, OcUAXS1/2, OcUGE1/2, OcUXE1/2, OcRHM1, OcNER1, OcG1cAE 1/2/3. And we studied the function and character of these enzymes and analysis expression level in different plant tissues.28 genes of potential glycosyltransferases was cloned in Ornithogalum caudatum, and we analysis the function of 3 enzymes (OcUGT 1/2/3). We found 2 glycosyltransferases have broad substrate spectra.It is important for us to research the biosynhthetic pathway of these UDP-sugars, and it is a significant part of nature products biosynthesis. Combining the sugar donor pathway with glycosyltransferase is a useful method to form nature product glycosylation. This article is aimed to discuss the research progress in studying biosynhthetic pathway of these UDP-sugars and analysis the functions and features in the pathway which can provide the logical proofs to nature products biosynthesis.