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Yuko Fukui - One of the best experts on this subject based on the ideXlab platform.

  • functional differentiation of the glycosyltransferases that contribute to the chemical diversity of bioactive flavonol glycosides in grapevines vitis vinifera
    The Plant Cell, 2010
    Co-Authors: Yu Homma, Yuko Fukui, Seiji Takahashi, Manabu Horikawa, Satoshi Kunikanedoi, Haruna Imai, Yosuke Kawai, Masaji Ishiguro, Toru Nakayama
    Abstract:

    We identified two glycosyltransferases that contribute to the structural diversification of flavonol glycosides in grapevine (Vitis vinifera): glycosyltransferase 5 (Vv GT5) and Vv GT6. Biochemical analyses showed that Vv GT5 is a UDP-glucuronic acid:flavonol-3-O-glucuronosyltransferase (GAT), and Vv GT6 is a bifunctional UDP-glucose/UDP-galactose:flavonol-3-O-glucosyltransferase/galactosyltransferase. The Vv GT5 and Vv GT6 genes have very high sequence similarity (91%) and are located in tandem on chromosome 11, suggesting that one of these genes arose from the other by gene duplication. Both of these enzymes were expressed in accordance with flavonol synthase gene expression and flavonoid distribution patterns in this plant, corroborating their significance in flavonol glycoside biosynthesis. The determinant of the specificity of Vv GT5 for UDP-glucuronic acid was found to be Arg-140, which corresponded to none of the determinants previously identified for other plant GATs in primary structures, providing another example of convergent evolution of plant GAT. We also analyzed the determinants of the sugar donor specificity of Vv GT6. Gln-373 and Pro-19 were found to play important roles in the bifunctional specificity of the enzyme. The results presented here suggest that the sugar donor specificities of these Vv GTs could be determined by a limited number of amino acid substitutions in the primary structures of protein duplicates, illustrating the plasticity of plant glycosyltransferases in acquiring new sugar donor specificities.

  • sequential glucosylation of a furofuran lignan sesaminol by sesamum indicum ugt71a9 and ugt94d1 Glucosyltransferases
    Plant Journal, 2008
    Co-Authors: Akio Noguchi, Yuko Fukui, Saki Kakutani, Honoo Satake, Takashi Iwashita, Masahiro Nakao, Toshiaki Umezawa, Asako Iuchiokada, Eiichiro Ono
    Abstract:

    (+)-Sesaminol 2-O-triglucoside is the most abundant water-soluble furofuran lignan in sesame seeds (Sesamum indicum) and is considered to be a beneficial compound for human health. The biosyntheses and physiological roles of lignan glycosides, however, remain elusive. Here we report the molecular identification and biochemical characterization of two Sesamum uridine diphosphate (UDP) glucose:lignan Glucosyltransferases. Sesamum indicum UGT71A9 preferentially glucosylated at the 2-hydroxyl group of (+)-sesaminol, resulting in (+)-sesaminol 2-O-glucoside. Similarly, two UGT71A9 homologs from Sesamum radiatum (UGT71A10) and Sesamum alatum (UGT71A8) also showed (+)-sesaminol glucosylating activity, evidencing the functional conservation of (+)-sesaminol 2-O-Glucosyltransferases in the Sesamum genus. In addition, S. indicum UGT94D1 specifically glucosylated at the 6'-hydroxyl group of the sugar moiety of (+)-sesaminol 2-O-glucoside but not at that of flavonoid glucosides. The gene expression patterns of UGT71A9 and UGT94D1 during seed development were correlated with the glucosylating activities toward (+)-sesaminol in planta, suggesting that the two lignan UDP-glycosyltransferases participate in the sequential glucosylation steps in the biosynthesis of (+)-sesaminol 2-O-triglucoside.

  • Sequential glucosylation of a furofuran lignan, (+)‐sesaminol, by Sesamum indicum UGT71A9 and UGT94D1 Glucosyltransferases
    The Plant Journal, 2008
    Co-Authors: Akio Noguchi, Yuko Fukui, Asako Iuchi-okada, Saki Kakutani, Honoo Satake, Takashi Iwashita, Masahiro Nakao, Toshiaki Umezawa, Eiichiro Ono
    Abstract:

    (+)-Sesaminol 2-O-triglucoside is the most abundant water-soluble furofuran lignan in sesame seeds (Sesamum indicum) and is considered to be a beneficial compound for human health. The biosyntheses and physiological roles of lignan glycosides, however, remain elusive. Here we report the molecular identification and biochemical characterization of two Sesamum uridine diphosphate (UDP) glucose:lignan Glucosyltransferases. Sesamum indicum UGT71A9 preferentially glucosylated at the 2-hydroxyl group of (+)-sesaminol, resulting in (+)-sesaminol 2-O-glucoside. Similarly, two UGT71A9 homologs from Sesamum radiatum (UGT71A10) and Sesamum alatum (UGT71A8) also showed (+)-sesaminol glucosylating activity, evidencing the functional conservation of (+)-sesaminol 2-O-Glucosyltransferases in the Sesamum genus. In addition, S. indicum UGT94D1 specifically glucosylated at the 6'-hydroxyl group of the sugar moiety of (+)-sesaminol 2-O-glucoside but not at that of flavonoid glucosides. The gene expression patterns of UGT71A9 and UGT94D1 during seed development were correlated with the glucosylating activities toward (+)-sesaminol in planta, suggesting that the two lignan UDP-glycosyltransferases participate in the sequential glucosylation steps in the biosynthesis of (+)-sesaminol 2-O-triglucoside.

  • biochemical and molecular characterization of a novel udp glucose anthocyanin 3 o glucosyltransferase a key enzyme for blue anthocyanin biosynthesis from gentian
    Plant Physiology, 2003
    Co-Authors: Masako Fukuchimizutani, Yuko Fukui, Masahiro Nakao, Takaaki Kusumi, Hiroaki Okuhara, Yukihisa Katsumoto, Keiko Yonekurasakakibara, Toshiharu Hase, Yoshikazu Tanaka
    Abstract:

    Gentian (Gentiana triflora) blue petals predominantly contain an unusually blue and stable anthocyanin, delphinidin 3-O-glucosyl-5-O-(6-O-caffeoyl-glucosyl)-3'-O-(6-O-caffeoyl-glucoside) (gentiodelphin). Glucosylation and the subsequent acylation of the 3'-hydroxy group of the B-ring of anthocyanins are important to the stabilization of and the imparting of bluer color to these anthocyanins. The enzymes and their genes involved in these modifications of the B-ring, however, have not been characterized, purified, or isolated to date. In this study, we purified a UDP-glucose (Glc):anthocyanin 3'-O-glucosyltransferase (3'GT) enzyme to homogeneity from gentian blue petals and isolated a cDNA encoding a 3'GT based on the internal amino acid sequences of the purified 3'GT. The deduced amino acid sequence indicates that 3'GT belongs to the same subfamily as a flavonoid 7-O-glucosyltransferase from Schutellaria baicalensis in the plant glucosyltransferase superfamily. Characterization of the enzymatic properties using the recombinant 3'GT protein revealed that, in contrast to most of flavonoid Glucosyltransferases, it has strict substrate specificity: 3'GT specifically glucosylates the 3'-hydroxy group of delphinidin-type anthocyanins containing Glc groups at 3 and 5 positions. The enzyme specifically uses UDP-Glc as the sugar donor. The specificity was confirmed by expression of the 3'GT cDNA in transgenic petunia (Petunia hybrida). This is the first report of the gene isolation of a B-ring-specific glucosyltransferase of anthocyanins, which paves the way to modification of flower color by production of blue anthocyanins.

  • two flavonoid Glucosyltransferases from petunia hybrida molecular cloning biochemical properties and developmentally regulated expression
    Plant Molecular Biology, 2002
    Co-Authors: Mami Yamazaki, Yuko Fukui, Yoshikazu Tanaka, Masako Fukuchimizutani, Takaaki Kusumi, Emiko Yamagishi, Zhizhong Gong, Masaatsu Yamaguchi, Kazuki Saito
    Abstract:

    Two flavonoid Glucosyltransferases, UDP-glucose:flavonoid 3-0-glucosyltransferase (3-GT) and UDP-glucose: anthocyanin 5-O-glucosyltransferase (5-GT), are responsible for the glucosylation of anthocyani(di)ns to produce stable molecules in the anthocyanin biosynthetic pathway. The cDNAs encoding 3-GT and 5-GT were isolated from Petunia hybrida by hybridization screening with heterologous probes. The cDNA clones of 3-GT, PGT8, and 5-GT, PH1, encode putative polypeptides of 448 and 468 amino acids, respectively. A phylogenetic tree based on amino acid sequences of the family of glycosyltransferases from various plants shows that PGT8 belongs to the 3-GT subfamily and PH1 belongs to the 5-GT subfamily. The function of isolated cDNAs was identified by the catalytic activities for 3-GT and 5-GT exhibited by the recombinant proteins produced in yeast. The recombinant PGT8 protein could convert not only anthocyanidins but also flavonols into the corresponding 3-O-glucosides. In contrast, the recombinant PH1 protein exhibited a strict substrate specificity towards anthocyanidin 3-acylrutinoside, comparing with other 5-GTs from Perilla frutescens and Verbena hybrida, which showed broad substrate specificities towards several anthocyanidin 3-glucosides. The mRNA expression of both 3-GT and 5-GT increased in the early developmental stages of P. hybrida flower, reaching the maximum at the stage before flower opening. Southern blotting analysis of genomic DNA indicates that both 3-GT and 5-GT genes exist in two copies in P. hybrida, respectively. The results are discussed in relation to the molecular evolution of flavonoid glycosyltransferases.

Ming Zeng - One of the best experts on this subject based on the ideXlab platform.

  • Functional Characterization of a Flavonoid Glycosyltransferase in Sweet Orange (Citrus sinensis)
    Frontiers in Plant Science, 2018
    Co-Authors: Xiaogang Liu, Cailing Lin, Yan Tan, Jiuzhao Wang, Ming Zeng
    Abstract:

    Fruits of sweet orange (Citrus sinensis), a popular commercial Citrus species, contains high concentrations of flavonoids beneficial to human health. These fruits predominantly accumulate O-glycosylated flavonoids, in which the disaccharides (neohesperidose (rhamnosyl-α-1,2-glucose) or rutinose (rhamnosyl-α-1,6-glucose)) are linked to the flavonoid aglycones through the 3- or 7-hydroxyl sites. The biotransformation of the flavonoid aglycones into O-rutinosides or O-neohesperidosides in the Citrus plants usually consists of two glycosylation reactions involving a series of uridine diphosphate (UDP)-sugar dependent glycosyltransferases (UGTs). Although several genes encoding flavonoid UGTs have been functionally characterized in the Citrus plants, full elucidation of the flavonoid glycosylation process remains elusive. Based on the available genomic and transcriptome data, we isolated a UGT with a high expression level in the sweet orange fruits that possibly encodes a flavonoid glucosyltransferase and/or rhamnosyltransferase. Biochemical analyses revealed that a broad range of flavonoid substrates could be glucosylated at their 3- and/or 7-hydrogen sites by the recombinant enzyme, including hesperetin, naringenin, diosmetin, quercetin, and kaempferol. Furthermore, overexpression of the gene could significantly increase the accumulation levels of quercetin 7-O-rhamnoside, quercetin 7-O-glucoside, and kaempferol 7-O-glucoside, implying that the enzyme has flavonoid 7-O-glucosyltransferase and 7-O-rhamnosyltransferase activities in vivo.

  • Functional Characterization of a Flavonoid Glycosyltransferase in Sweet Orange (Citrus sinensis)
    Frontiers Media S.A., 2018
    Co-Authors: Xiaogang Liu, Cailing Lin, Yan Tan, Jiuzhao Wang, Ming Zeng
    Abstract:

    Fruits of sweet orange (Citrus sinensis), a popular commercial Citrus species, contain high concentrations of flavonoids beneficial to human health. These fruits predominantly accumulate O-glycosylated flavonoids, in which the disaccharides [neohesperidose (rhamnosyl-α-1,2-glucose) or rutinose (rhamnosyl-α-1,6-glucose)] are linked to the flavonoid aglycones through the 3- or 7-hydroxyl sites. The biotransformation of the flavonoid aglycones into O-rutinosides or O-neohesperidosides in the Citrus plants usually consists of two glycosylation reactions involving a series of uridine diphosphate-sugar dependent glycosyltransferases (UGTs). Although several genes encoding flavonoid UGTs have been functionally characterized in the Citrus plants, full elucidation of the flavonoid glycosylation process remains elusive. Based on the available genomic and transcriptome data, we isolated a UGT with a high expression level in the sweet orange fruits that possibly encodes a flavonoid glucosyltransferase and/or rhamnosyltransferase. Biochemical analyses revealed that a broad range of flavonoid substrates could be glucosylated at their 3- and/or 7-hydrogen sites by the recombinant enzyme, including hesperetin, naringenin, diosmetin, quercetin, and kaempferol. Furthermore, overexpression of the gene could significantly increase the accumulations of quercetin 7-O-rhamnoside, quercetin 7-O-glucoside, and kaempferol 7-O-glucoside, implying that the enzyme has flavonoid 7-O-glucosyltransferase and 7-O-rhamnosyltransferase activities in vivo

Akio Noguchi - One of the best experts on this subject based on the ideXlab platform.

  • identification of an inducible glucosyltransferase from phytolacca americana l cells that are capable of glucosylating capsaicin
    Plant Biotechnology, 2009
    Co-Authors: Akio Noguchi, Hisashi Katsuragi, Satoshi Kunikane, Hiroaki Homma, Takashi Sekiya, Miho Hosoya, Soonil Kwon, Shingo Ohiwa, Tokuzo Nishino, Seiji Takahashi
    Abstract:

    Cell suspension cultures of Phytolacca americana L. (pokeweed) are capable of glycosylating capsaicinoids that have several biomedical applications. To identify the capsaicinoid glucosyltransferase involved in this biotransformation, we isolated three full-length cDNAs (PaGTs) encoding homologs of plant secondary product glycosyltransferases from cultured cells of P. americana L. These glycosyltransferase cDNAs were heterologously expressed in Escherichia coli cells and the expressed products were functionally characterized. Although all of these glycosyltransferases displayed broad glucosyl-acceptor specificities toward phenolics, capsaicinoid glucosyltransferase activity was found only for one of the cloned enzymes, PaGT3. Phylogenetic analysis showed that PaGT3 is the most closely related to betanidin 5-O-glucosyltransferase from Dorotheanthus bellidiformis, and in fact, it displayed a weak betanidin 5-O-glucosyltransferase activity. Transcription analyses showed that the expression of PaGT3 in P. americana L. was strongly induced by exposure of the cells to capsaicin (0.65 mM). These results show that PaGT3 should be, at least in part, responsible for the capsaicinoid glucosyltransferase activity of this plant.

  • sequential glucosylation of a furofuran lignan sesaminol by sesamum indicum ugt71a9 and ugt94d1 Glucosyltransferases
    Plant Journal, 2008
    Co-Authors: Akio Noguchi, Yuko Fukui, Saki Kakutani, Honoo Satake, Takashi Iwashita, Masahiro Nakao, Toshiaki Umezawa, Asako Iuchiokada, Eiichiro Ono
    Abstract:

    (+)-Sesaminol 2-O-triglucoside is the most abundant water-soluble furofuran lignan in sesame seeds (Sesamum indicum) and is considered to be a beneficial compound for human health. The biosyntheses and physiological roles of lignan glycosides, however, remain elusive. Here we report the molecular identification and biochemical characterization of two Sesamum uridine diphosphate (UDP) glucose:lignan Glucosyltransferases. Sesamum indicum UGT71A9 preferentially glucosylated at the 2-hydroxyl group of (+)-sesaminol, resulting in (+)-sesaminol 2-O-glucoside. Similarly, two UGT71A9 homologs from Sesamum radiatum (UGT71A10) and Sesamum alatum (UGT71A8) also showed (+)-sesaminol glucosylating activity, evidencing the functional conservation of (+)-sesaminol 2-O-Glucosyltransferases in the Sesamum genus. In addition, S. indicum UGT94D1 specifically glucosylated at the 6'-hydroxyl group of the sugar moiety of (+)-sesaminol 2-O-glucoside but not at that of flavonoid glucosides. The gene expression patterns of UGT71A9 and UGT94D1 during seed development were correlated with the glucosylating activities toward (+)-sesaminol in planta, suggesting that the two lignan UDP-glycosyltransferases participate in the sequential glucosylation steps in the biosynthesis of (+)-sesaminol 2-O-triglucoside.

  • Sequential glucosylation of a furofuran lignan, (+)‐sesaminol, by Sesamum indicum UGT71A9 and UGT94D1 Glucosyltransferases
    The Plant Journal, 2008
    Co-Authors: Akio Noguchi, Yuko Fukui, Asako Iuchi-okada, Saki Kakutani, Honoo Satake, Takashi Iwashita, Masahiro Nakao, Toshiaki Umezawa, Eiichiro Ono
    Abstract:

    (+)-Sesaminol 2-O-triglucoside is the most abundant water-soluble furofuran lignan in sesame seeds (Sesamum indicum) and is considered to be a beneficial compound for human health. The biosyntheses and physiological roles of lignan glycosides, however, remain elusive. Here we report the molecular identification and biochemical characterization of two Sesamum uridine diphosphate (UDP) glucose:lignan Glucosyltransferases. Sesamum indicum UGT71A9 preferentially glucosylated at the 2-hydroxyl group of (+)-sesaminol, resulting in (+)-sesaminol 2-O-glucoside. Similarly, two UGT71A9 homologs from Sesamum radiatum (UGT71A10) and Sesamum alatum (UGT71A8) also showed (+)-sesaminol glucosylating activity, evidencing the functional conservation of (+)-sesaminol 2-O-Glucosyltransferases in the Sesamum genus. In addition, S. indicum UGT94D1 specifically glucosylated at the 6'-hydroxyl group of the sugar moiety of (+)-sesaminol 2-O-glucoside but not at that of flavonoid glucosides. The gene expression patterns of UGT71A9 and UGT94D1 during seed development were correlated with the glucosylating activities toward (+)-sesaminol in planta, suggesting that the two lignan UDP-glycosyltransferases participate in the sequential glucosylation steps in the biosynthesis of (+)-sesaminol 2-O-triglucoside.

Hajime Mizukami - One of the best experts on this subject based on the ideXlab platform.

  • Functional and structural characterization of a flavonoid glucoside 1,6-glucosyltransferase from Catharanthus roseus.
    Plant and Cell Physiology, 2009
    Co-Authors: Sayaka Masada, Yukie Oguchi, Seiji Okazaki, Tunehiro Mizushima, Kazuyoshi Terasaka, Hajime Mizukami
    Abstract:

    Sugar-sugar glycosyltransferases play an important role in structural diversity of small molecule glycosides in higher plants. We isolated a cDNA clone encoding a sugar-sugar glucosyltransferase (CaUGT3) catalyzing 1,6-glucosylation of flavonol and flavone glucosides for the first time from Catharanthus roseus. CaUGT3 exhibited a unique glucosyl chain elongation activity forming not only gentiobioside but also gentiotrioside and gentiotetroside in a sequential manner. We investigated the functional properties of CaUGT3 using homology modeling and site-directed mutagenesis, and identified amino acids positioned in the acceptor-binding pocket as crucial for providing enough space to accommodate flavonoid glucosides instead of flavonoid aglycones. These results provide basic information for understanding and engineering the catalytic functions of sugar-sugar glycosyltransferases involved in biosynthesis of plant glycosides.

  • an efficient chemoenzymatic production of small molecule glucosides with in situ udp glucose recycling
    FEBS Letters, 2007
    Co-Authors: Sayaka Masada, Yukie Oguchi, Kazuyoshi Terasaka, Yoji Kawase, Mai Nagatoshi, Hajime Mizukami
    Abstract:

    A one-pot system for efficient enzymatic synthesis of curcumin glucosides is described. The method couples the activities of two recombinant enzymes, UDP-glucose: curcumin glucosyltransferase from Catharanthus roseus (CaUGT2) and sucrose synthase from Arabidopsis thaliana (AtSUS1). UDP, a product inhibitor of UDP-glucosyltransferase, was removed from the system and used for regeneration of UDP-glucose by the second enzyme, AtSUS1. The productivity was increased several-fold and UDP-glucose initially added to the reaction mixture could be reduced to one-tenth of the normal level. The concept of enhancing glucosylation efficiency by coupling a UDP-glucose regeneration system with Glucosyltransferases should be applicable to enzymatic production of a wide range of glucosides.

  • molecular cloning and characterization of a glucosyltransferase catalyzing glucosylation of curcumin in cultured catharanthus roseus cells
    FEBS Letters, 2004
    Co-Authors: Yasuhisa Kaminaga, Pinar F Sahin, Hajime Mizukami
    Abstract:

    Catharanthus roseus cell suspension cultures are capable of converting exogenously supplied curcumin to various glucosides. The glucosylation efficiency is enhanced by addition of methyl jasmonate (MJ) to the cultures prior to curcumin administration. Two cDNAs encoding UDP-Glucosyltransferases (CaUGT1 and CaUGT2) were isolated from a cDNA library of cultured C. roseus cells, using a PCR method directed at the conserved UDP-binding domain of plant glycosyltransferases. The sequence identity between their deduced amino acid sequences was 27%. The expression of both genes was up-regulated by addition of MJ to the cell cultures although the mRNA level of CaUGT1 was much lower than that of CaUGT2. The corresponding cDNAs were expressed in Escherichia coli as fusion proteins with maltose-binding protein. The recombinant CaUGT1 exhibited no glucosylation activity with either curcumin or curcumin monoglucoside as substrate, whereas the recombinant CaUGT2 catalyzed the formation of curcumin monoglucoside from curcumin and also conversion of curcumin monoglucoside to curcumin diglucoside. The use of the recombinant CaUGT2 may provide a useful new route for the production of curcumin glucosides.

Wei Wang - One of the best experts on this subject based on the ideXlab platform.

  • identification and characterization of two new 1 o acyl glucose ester forming Glucosyltransferases from erigeron breviscapus
    Journal of Agricultural and Food Chemistry, 2019
    Co-Authors: Yan Yang, Minzhi Liu, Wenxuan Zhang, Yunsong Cao, Wei Wang
    Abstract:

    Two versatile UDP-Glucosyltransferases, UGT75L25 and UGT75X1, were isolated from Erigeron breviscapus. The enzymes display high sequence identity to flavonoid 7- O-glucosyltransferase from Malus species and cluster to the phylogenetic group L of plant Glucosyltransferases, also involved in the formation of hydroxycinnamoyl glucose esters, which are used as bifunctional donors in the glucosylation or acylation of anthocyanins. The enzymes, functionally expressed in Escherichia coli, exhibit broad substrate specificity toward 21 structurally diverse types of phenolic acids, including (hydroxy)cinnamates, vanillic acid, 3-hydroxycoumarin, and 7-hydroxyflavonoids. The catalytic characteristics of UGT75L25 and UGT75X1 were exploited to generate the corresponding acyl-glucose-esters or glucosides with high efficiency. These findings demonstrate the significant potential of acyl-glucose-esters in the further enzymatic synthesis of bioactive anthocyanins.

  • Identification and Characterization of Two New 1‑O‑Acyl-glucose-ester Forming Glucosyltransferases from Erigeron breviscapus
    2019
    Co-Authors: Yan Yang, Minzhi Liu, Wenxuan Zhang, Yunsong Cao, Wei Wang
    Abstract:

    Two versatile UDP-Glucosyltransferases, UGT75L25 and UGT75X1, were isolated from Erigeron breviscapus. The enzymes display high sequence identity to flavonoid 7-O-glucosyltransferase from Malus species and cluster to the phylogenetic group L of plant Glucosyltransferases, also involved in the formation of hydroxycinnamoyl glucose esters, which are used as bifunctional donors in the glucosylation or acylation of anthocyanins. The enzymes, functionally expressed in Escherichia coli, exhibit broad substrate specificity toward 21 structurally diverse types of phenolic acids, including (hydroxy)­cinnamates, vanillic acid, 3-hydroxycoumarin, and 7-hydroxyflavonoids. The catalytic characteristics of UGT75L25 and UGT75X1 were exploited to generate the corresponding acyl-glucose-esters or glucosides with high efficiency. These findings demonstrate the significant potential of acyl-glucose-esters in the further enzymatic synthesis of bioactive anthocyanins