title: Synthesis of flavonoid O-pentosides by Escherichia coli through engineering of nucleotide sugar pathways and glycosyltransferase.
abstract: Plants produce two flavonoid O-pentoses, flavonoid O-xyloside and flavonoid O-arabinoside. However, analyzing their biological properties is difficult because flavonoids are not naturally produced in sufficient quantities. In this study, Escherichia coli was used to synthesize the plant-specific flavonoid O-pentosides quercetin 3-O-xyloside and quercetin 3-O-arabinoside. Two strategies were used. First, E. coli was engineered to express components of the biosynthetic pathways for UDP-xylose and UDP-arabinose. For UDP-xylose biosynthesis, two genes, UXS (UDP-xylose synthase) from Arabidopsis thaliana and ugd (UDP-glucose dehydrogenase) from E. coli, were overexpressed. In addition, the gene encoding ArnA (UDP-l-Ara4N formyltransferase/UDP-GlcA C-4″-decarboxylase), which competes with UXS for UDP-glucuronic acid, was deleted. For UDP-arabinose biosynthesis, UXE (UDP-xylose epimerase) was overexpressed. Next, we engineered UDP-dependent glycosyltransferases (UGTs) to ensure specificity for UDP-xylose and UDP-arabinose. The E. coli strains thus obtained synthesized approximately 160 mg/liter of quercetin 3-O-xyloside and quercetin 3-O-arabinoside.
authors.affiliation: Department of Bioscience and Biotechnology, Bio/Molecular Informatics Center, Konkuk University, Seoul, South Korea.
authors.forename: So Hyun
authors.initials: SH
authors.lastname: Han
authors.forename: Bong Gyu
authors.initials: BG
authors.lastname: Kim
authors.forename: Jeong A
authors.initials: JA
authors.lastname: Yoon
authors.forename: Youhoon
authors.initials: Y
authors.lastname: Chong
authors.forename: Joong-Hoon
authors.initials: JH
authors.lastname: Ahn
mesh_terms: D017360:Arabidopsis / Q000201:enzymology / Q000235:genetics; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism; D001089:Arabinose / Q000378:metabolism*; D053898:Biosynthetic Pathways; D002262:Carboxy-Lyases / Q000235:genetics / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics* / Q000378:metabolism*; D005419:Flavonoids / Q000737:chemistry / Q000378:metabolism*; D016695:Glycosyltransferases / Q000235:genetics / Q000378:metabolism; D060847:Metabolic Engineering; D014533:Uridine Diphosphate Glucose Dehydrogenase / Q000235:genetics / Q000378:metabolism; D014539:Uridine Diphosphate Sugars / Q000378:metabolism; D014994:Xylose / Q000378:metabolism*
chemical_list: D029681:Arabidopsis Proteins; D005419:Flavonoids; D014539:Uridine Diphosphate Sugars; C040817:uridine diphosphate arabinose; D014994:Xylose; D001089:Arabinose; D014533:Uridine Diphosphate Glucose Dehydrogenase; D016695:Glycosyltransferases; D002262:Carboxy-Lyases; C023257:UDPglucuronate decarboxylase