title: Enzymatic and metabolic engineering for efficient production of syringin, sinapyl alcohol 4-O-glucoside, in Arabidopsis thaliana.
abstract: To promote efficient production of syringin, a plant-derived bioactive monolignol glucoside, synergistic effects of enzymatic and metabolic engineering were combined. Recombinant UGT72E3/E2 chimeras, generated by exchanging parts of the C-terminal domain including the Putative Secondary Plant Glycosyltransferase (PSPG) motif of UGT72E3 and UGT72E2, were expressed in leaves of transgenic Arabidopsis plants; syringin production was measured in vivo and by enzymatic assays in vitro. In both tests, UGT72E3/2 displayed substrate specificity for sinapyl alcohol like the parental enzyme UGT72E3, and the syringin production was significantly increased compared to UGT72E3. In particular, in the in vitro assay, which was performed in the presence of a high concentration of sinapyl alcohol, the production of syringin by UGT72E3/2 was 4-fold higher than by UGT72E3. Furthermore, to enhance metabolic flow through the phenylpropanoid pathway and maintain a high basal concentration of sinapyl alcohol in the leaves, UGT72E3/2 was combined with the sinapyl alcohol synthesis pathway gene F5H encoding ferulate 5-hydroxylase and the lignin biosynthesis transcriptional activator MYB58. The resulting UGT72E3/2+F5H+MYB58 OE plants, which simultaneously overexpress these three genes, accumulated a 56-fold higher level of syringin in their leaves than wild-type plants.
authors.affiliation: Department of Molecular Biotechnology, Dong-A University, Busan 604-714, South Korea.
authors.forename: Yang
authors.initials: Y
authors.lastname: Chu
authors.affiliation: Department of Molecular Biotechnology, Dong-A University, Busan 604-714, South Korea.
authors.forename: Tackmin
authors.initials: T
authors.lastname: Kwon
authors.affiliation: Department of Molecular Biotechnology, Dong-A University, Busan 604-714, South Korea. Electronic address: jnam@dau.ac.kr.
authors.forename: Jaesung
authors.initials: J
authors.lastname: Nam
mesh_terms: D017360:Arabidopsis / Q000201:enzymology / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000737:chemistry / Q000378:metabolism*; D003577:Cytochrome P-450 Enzyme System / Q000737:chemistry / Q000378:metabolism*; D005960:Glucosides / Q000096:biosynthesis* / Q000737:chemistry; D005964:Glucosyltransferases / Q000737:chemistry / Q000378:metabolism*; D060847:Metabolic Engineering; D008958:Models, Molecular; D015394:Molecular Structure; D010666:Phenylpropionates / Q000737:chemistry; D015534:Trans-Activators / Q000737:chemistry / Q000378:metabolism*; D015533:Transcriptional Activation
chemical_list: D029681:Arabidopsis Proteins; D005960:Glucosides; C000593916:MYB58 protein, Arabidopsis; D010666:Phenylpropionates; D015534:Trans-Activators; D003577:Cytochrome P-450 Enzyme System; C097486:CYP84A1 protein, Arabidopsis; D005964:Glucosyltransferases; C515049:UGT72E2 protein, Arabidopsis; C000593915:UGT72E3 protein, Arabidopsis; C028305:syringin
keywords: Arabidopsis thaliana; Coniferin; Coniferyl alcohol 4-O-glucoside; Cruciferae; Gene stacking; Glucosyltransferase 72E family; Monolignol biosynthesis; Phenylpropanoid pathway; Sinapyl alcohol 4-O-glucoside; Syringin