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Birger Lindberg Moller - One of the best experts on this subject based on the ideXlab platform.

  • metabolic consequences of knocking out ugt85b1 the gene encoding the Glucosyltransferase required for synthesis of dhurrin in sorghum bicolor l moench
    Plant and Cell Physiology, 2016
    Co-Authors: Cecilia K Blomstedt, Natalie Odonnell, John D Hamill, Alan D Neale, Nanna Bjarnholt, Birger Lindberg Moller, Roslyn M Gleadow
    Abstract:

    Many important food crops produce cyanogenic glucosides as natural defense compounds to protect against herbivory or pathogen attack. It has also been suggested that these nitrogen-based secondary metabolites act as storage reserves of nitrogen. In sorghum, three key genes, CYP79A1, CYP71E1 and UGT85B1, encode two Cytochrome P450s and a glycosyltransferase, respectively, the enzymes essential for synthesis of the cyanogenic glucoside dhurrin. Here, we report the use of targeted induced local lesions in genomes (TILLING) to identify a line with a mutation resulting in a premature stop codon in the N-terminal region of UGT85B1. Plants homozygous for this mutation do not produce dhurrin and are designated tcd2 (totally cyanide deficient 2) mutants. They have reduced vigor, being dwarfed, with poor root development and low fertility. Analysis using liquid chromatography-mass spectrometry (LC-MS) shows that tcd2 mutants accumulate numerous dhurrin pathway-derived metabolites, some of which are similar to those observed in transgenic Arabidopsis expressing the CYP79A1 and CYP71E1 genes. Our results demonstrate that UGT85B1 is essential for formation of dhurrin in sorghum with no co-expressed endogenous UDP-Glucosyltransferases able to replace it. The tcd2 mutant suffers from self-intoxication because sorghum does not have a feedback mechanism to inhibit the initial steps of dhurrin biosynthesis when the Glucosyltransferase activity required to complete the synthesis of dhurrin is lacking. The LC-MS analyses also revealed the presence of metabolites in the tcd2 mutant which have been suggested to be derived from dhurrin via endogenous pathways for nitrogen recovery, thus indicating which enzymes may be involved in such pathways.

  • the udp glucose p hydroxymandelonitrile o Glucosyltransferase that catalyzes the last step in synthesis of the cyanogenic glucoside dhurrin in sorghum bicolor isolation cloning heterologous expression and substrate specificity
    Journal of Biological Chemistry, 1999
    Co-Authors: Patrik R Jones, Birger Lindberg Moller
    Abstract:

    Abstract The final step in the biosynthesis of the cyanogenic glucoside dhurrin in Sorghum bicolor is the transformation of the labile cyanohydrin into a stable storage form byO-glucosylation of (S)-p-hydroxymandelonitrile at the cyanohydrin function. The UDP-glucose:p-hydroxymandelonitrile-O-Glucosyltransferase was isolated from etiolated seedlings of S. bicoloremploying Reactive Yellow 3 chromatography with UDP-glucose elution as the critical step. Amino acid sequencing allowed the cloning of a full-length cDNA encoding the Glucosyltransferase. Among the few characterized Glucosyltransferases, the deduced translation product showed highest overall identity to Zea maysflavonoid-Glucosyltransferase (Bz-Mc-2 allele). The substrate specificity of the enzyme was established using isolated recombinant protein. Compared with endogenousp-hydroxymandelonitrile, mandelonitrile, benzyl alcohol, and benzoic acid were utilized at maximum rates of 78, 13, and 4%, respectively. Surprisingly, the monoterpenoid geraniol was glucosylated at a maximum rate of 11% compared withp-hydroxymandelonitrile. The picture that is emerging regarding plant Glucosyltransferase substrate specificity is one of limited but extended plasticity toward metabolites of related structure. This in turn ensures that a relatively high, but finite, number of Glucosyltransferases can give rise to the large number of glucosides found in plants.

William R. Belknap - One of the best experts on this subject based on the ideXlab platform.

  • the primary in vivo steroidal alkaloid Glucosyltransferase from potato
    Phytochemistry, 2006
    Co-Authors: Kent F. Mccue, Louise V T Shepherd, Paul V Allen, Malendia M Maccree, David R Rockhold, H V Davies, Alison Blake, Jonathan L Whitworth, Derek Stewart, William R. Belknap
    Abstract:

    To provide tools for breeders to control the steroidal glycoalkaloid (SGA) pathway in potato, we have investigated the steroidal alkaloid glycosyltransferase (Sgt) gene family. The committed step in the SGA pathway is the glycosylation of solanidine by either UDP-glucose or UDP-galactose leading to alpha-chaconine or alpha-solanine, respectively. The Sgt2 gene was identified by deduced protein sequence homology to the previously identified Sgt1 gene. SGT1 has Glucosyltransferase activity in vitro, but in vivo serves as the UDP-galactose:solanidine galactosyltransferase. Two alleles of the Sgt2 gene were isolated and its function was established with antisense transgenic lines and in vitro assays of recombinant protein. In tubers of transgenic potato (Solanum tuberosum) cvs. Lenape and Desiree expressing an antisense Sgt2 gene construct, accumulation of alpha-solanine was increased and alpha-chaconine was reduced. Studies with recombinant SGT2 protein purified from yeast show that SGT2 glycosylation activity is highly specific for UDP-glucose as a sugar donor. This data establishes the function of the gene product (SGT2), as the primary UDP-glucose:solanidine Glucosyltransferase in vivo.

  • metabolic compensation of steroidal glycoalkaloid biosynthesis in transgenic potato tubers using reverse genetics to confirm the in vivo enzyme function of a steroidal alkaloid galactosyltransferase
    Plant Science, 2005
    Co-Authors: Kent F. Mccue, Louise V T Shepherd, Paul V Allen, Malendia M Maccree, David R Rockhold, H V Davies, Dennis L. Corsini, William R. Belknap
    Abstract:

    Steroidal glycoalkaloids (SGAs) are secondary metabolites of Solanaceous plants. Two predominant glycoalkaloids, a-chaconine and asolanine are produced in potatoes. An antisense transgene was constructed to down-regulate glycoalkaloid biosynthesis using a potato cDNA encoding a sterol alkaloid glycosyltransferase (Sgt1). Introduction of this construct into potatoes resulted in some lines with an almost complete inhibition of a-solanine accumulation. This inhibition was compensated by elevated levels of a-chaconine and resulted in wild type total SGA levels in the transgenic lines. In vitro assays with the recombinant SGT1 isolated from yeast demonstrated that Sgt1 encodes an enzyme capable of both Glucosyltransferase and galactosyltransferase activity with a preference for UDP-galactose as the sugar donor. Together this data confirms SGT1’s role in vivo as the solanidine:UDP-galactose galactosyltransferase. # 2004 Elsevier Ireland Ltd. All rights reserved.

  • cloning and expression of solanidine udp glucose Glucosyltransferase from potato
    Plant Journal, 1997
    Co-Authors: Charles P. Moehs, Paul V Allen, Mendel Friedman, William R. Belknap
    Abstract:

    A cDNA encoding solanidine Glucosyltransferase (SGT) was isolated from potato. The cDNA was selected from a yeast expression library using a positive selection based on the higher toxicity of steroidal alkaloid aglycons relative to their associated glycosylated forms. The cDNA contained an open reading frame encoding a 56 kDa polypeptide with regions of similarity to previously characterized UDP-Glucosyltransferases. The enzyme activity and reaction products of recombinant SGT in yeast were consistent with those observed for the endogenous enzyme from potato. SGT mRNA and protein accumulated in tubers in response to wounding. The time course for SGT mRNA accumulation paralleled that of 3-hydroxy-3-methylglutaryl-coenzymeA isoform 1 (hmg1) mRNA. Steady-state SGT mRNA levels also increased transiently upon wounding of leaves.

Ernst Heinz - One of the best experts on this subject based on the ideXlab platform.

  • Glycolipid headgroup replacement: A new approach for the analysis of specific functions of glycolipids in vivo
    European Journal of Cell Biology, 2009
    Co-Authors: Dirk Warnecke, Ernst Heinz
    Abstract:

    Glycolipids with one or two sugar residues attached to different lipid backbones are found in biomembranes of bacteria, fungi, plants and animals in the form of steryl glycosides, glycosylceramides and diacylglycerol glycosides. They contain different sugar residues, mainly glucose and galactose, in either α- or β-configuration. Many of the isolated compounds have been studied in great detail with regard to their biophysical behavior in artificial membrane systems. With the availability of cloned genes, the methods of reverse genetics were used to study glycolipid functions in living cells. The deletion of a lipid glycosyltransferase gene leads to the loss of the corresponding glycolipid in the transformed pro- and eukaryotic organisms. Often, these glycosyltransferase deletion mutants showed many differences to the wild-type organisms and thus demonstrated the biological importance of the glycolipid. When extensive deletion-induced glycolipid losses were not complemented by higher proportions of other membrane lipids, the mutants could display severe phenotypes due to a serious dysfunction or even collapse of an entire membrane system. On the other hand, by this approach the specific contribution of characteristic head group details cannot be recognized and separated from more general glycolipid functions. Many of these difficulties can be circumvented by a glycolipid headgroup replacement approach. This new approach requires the exchange of a lipid glycosyltransferase in an organism by a heterologous glycosyltransferase having a different headgroup specificity, e.g. the substitution of a galactosyltransferase by a Glucosyltransferase. The resulting transgenic organism produces a novel glycolipid which differs from that of the native organism not in proportion, but only in structural details of its headgroup. Therefore, such rescued mutants are comparable to suppressor mutants and show less severe phenotypes than the intermediate deletion mutants. A comparison between the wild type, the simple deletion mutant and the mutant rescued by glycolipid replacement will not only disclose general functions of glycolipids, but also additional roles of headgroup details.

  • Cloning of a cholesterol-alpha-Glucosyltransferase from Helicobacter pylori
    The Journal of biological chemistry, 2006
    Co-Authors: Ah Lebrun, Ernst Heinz, Ulrich Zähringer, Christian Wunder, Hildebrand Janosch, Yuri Churin, Buko Lindner, Thomas F. Meyer, Dirk Warnecke
    Abstract:

    O-Glycans of the human gastric mucosa show antimicrobial activity against the pathogenic bacterium Helicobacter pylori by inhibiting the bacterial cholesterol-alpha-Glucosyltransferase (Kawakubo, M., Ito, Y., Okimura, Y., Kobayashi, M., Sakura, K., Kasama, S., Fukuda, M. N., Fukuda, M., Katsuyama, T., and Nakayama, J. (2004) Science 305, 1003-1006). This enzyme catalyzes the first step in the biosynthesis of four unusual glycolipids: cholesteryl-alpha-glucoside, cholesteryl-6'-O-acyl-alpha-glucoside, cholesteryl-6'-O-phosphatidyl-alpha-glucoside, and cholesteryl-6'-O-lysophosphatidyl-alpha-glucoside. Here we report the identification, cloning, and functional characterization of the cholesterol-alpha-Glucosyltransferase from H. pylori. The hypothetical protein HP0421 from H. pylori belongs to the glycosyltransferase family 4 and shows similarities to some bacterial diacylglycerol-alpha-Glucosyltransferases. Deletion of the HP0421 gene in H. pylori resulted in the loss of cholesteryl-alpha-glucoside and all of its three derivatives. Heterologous expression of HP0421 in the yeast Pichia pastoris led to the biosynthesis of ergosteryl-alpha-glucoside as demonstrated by purification of the lipid and subsequent structural analysis by nuclear magnetic resonance spectroscopy and mass spectrometry. In vitro enzyme assays were performed with cell-free homogenates obtained from cells of H. pylori or from transgenic Escherichia coli, which express HP0421. These assays revealed that the enzyme represents a membrane-bound, UDP-glucose-dependent cholesterol-alpha-Glucosyltransferase.

  • Glycoengineering of Cyanobacterial Thylakoid Membranes for Future Studies on the Role of Glycolipids in Photosynthesis
    Plant and Cell Physiology, 2005
    Co-Authors: Georg Hölzl, Dirk Warnecke, Ulrich Zähringer, Ernst Heinz
    Abstract:

    The lipid composition of thylakoid membranes is conserved from cyanobacteria to angiosperms. The predominating components are monogalactosyl- and digalactosyldiacylglycerol. In cyanobacteria, thylakoid membrane biosynthesis starts with the formation of monoglucosyldiacylglycerol which is C4-epimerized to the corresponding galactolipid, whereas in plastids monogalactosyldiacylglycerol is formed at the beginning. This suggests that galactolipids have specific functions in thylakoids. We wanted to investigate whether galactolipids can be replaced by glycosyldiacylglycerols with headgroups differing in their epimeric and anomeric details as well as the attachment point of the terminal hexose in diglycosyldiacylglycerols. For this purpose putative glycosyltransferase sequences were identified in databases to be used for functional expression in various host organisms. From 18 newly identified sequences, four turned out to encode glycosyltransferases catalyzing final steps in glycolipid biosynthesis: two alpha-Glucosyltransferases, one beta-galactosyltransferase and one beta-Glucosyltransferase. Their functional annotation was based on detailed structural characterization of the new glycolipids formed in the transformant hosts as well as on in vitro enzymatic assays. The expression of alpha-Glucosyltransferases in the cyanobacterium Synechococcus resulted in the accumulation of the new alpha-galactosyldiacylglycerol which is ascribed to epimerization of the corresponding glucolipid. The expression of the beta-Glucosyltransferase led to a high proportion of new beta-glucosyl-(1-->6)-beta-galactosyldiacylglycerol almost entirely replacing the native digalactosyldiacylglycerol. These results demonstrate that modifications of the glycolipid pattern in thylakoids are possible.

  • processive lipid galactosyl Glucosyltransferases from agrobacterium tumefaciens and mesorhizobium loti display multiple specificities
    Glycobiology, 2005
    Co-Authors: Georg Hölzl, Dirk Warnecke, Ulrich Zähringer, Buko Lindner, Martina Leipelt, Ernst Heinz
    Abstract:

    The glycosyltransferase family 21 (GT21) includes both enzymes of eukaryotic and prokaryotic organisms. Many of the eukaryotic enzymes from animal, plant, and fungal origin have been characterized as uridine diphosphoglucose (UDP-Glc):ceramide Glucosyltransferases (glucosylceramide synthases [Gcs], EC 2.4.1.80). As the acceptor molecule ceramide is not present in most bacteria, the enzymatic specificities and functions of the corresponding bacterial glycosyltransferases remain elusive. In this study, we investigated the homologous and heterologous expression of GT21 enzymes from Agrobacterium tumefaciens and Mesorhizobium loti in A. tumefaciens, Escherichia coli, and the yeast Pichia pastoris. Glycolipid analyses of the transgenic organisms revealed that the bacterial glycosyltransferases are involved in the synthesis of mono-, di- and even tri-glycosylated glycolipids. As products resulting from their activity, we identified 1,2-diacyl-3-(O-beta-D-galacto-pyranosyl)-sn-glycerol, 1,2-diacyl-3-(O-beta-D-gluco-pyranosyl)-sn-glycerol as well as higher glycosylated lipids such as 1,2-diacyl-3-[O-beta-D-galacto-pyranosyl-(1-->6)-O-beta-D-galacto-pyranosyl]-sn-glycerol, 1,2-diacyl-3-[O-beta-D-gluco-pyranosyl-(1-->6)-O-beta-D-galacto-pyranosyl]-sn-glycerol, 1,2-diacyl-3-[O-beta-D-gluco-pyranosyl-(1-->6)-O-beta-D-gluco-pyranosyl]-sn-glycerol, and the deviatingly linked diglycosyldiacylglycerol 1,2-diacyl-3-[O-beta-D-gluco-pyranosyl-(1-->3)-O-beta-D-galacto-pyranosyl]-sn-glycerol. From a mixture of triglycosyldiacylglycerols, 1,2-diacyl-3-[O-beta-D-galacto-pyranosyl-(1-->6)-O-beta-D-galacto-pyranosyl-(1-->6)-O-beta-D-galacto-pyranosyl]-sn-glycerol could be separated in a pure form. In vitro enzyme assays showed that the glycosyltransferase from A. tumefaciens favours uridine diphosphogalactose (UDP-Gal) over UDP-Glc. In conclusion, the bacterial GT21 enzymes differ from the eukaryotic ceramide Glucosyltransferases by the successive transfer of up to three galactosyl and glucosyl moieties to diacylglycerol.

  • peroxisome degradation requires catalytically active sterol Glucosyltransferase with a gram domain
    The EMBO Journal, 2003
    Co-Authors: Masahide Oku, Dirk Warnecke, Ernst Heinz, Takeshi Noda, Frank W Muller, Hiroyuki Mukaiyama, Nobuo Kato, Yasuyoshi Sakai
    Abstract:

    Fungal sterol Glucosyltransferases, which synthesize sterol glucoside (SG), contain a GRAM domain as well as a pleckstrin homology and a catalytic domain. The GRAM domain is suggested to play a role in membrane traffic and pathogenesis, but its significance in any biological processes has never been experimentally demonstrated. We describe herein that sterol Glucosyltransferase (Ugt51/Paz4) is essential for pexophagy (peroxisome degradation), but not for macroautophagy in the methylotrophic yeast Pichia pastoris. By expressing truncated forms of this protein, we determined the individual contributions of each of these domains to pexophagy. During micropexophagy, the Glucosyltransferase was associated with a recently identified membrane structure: the micropexophagic apparatus. A single amino acid substitution within the GRAM domain abolished this association as well as micropexophagy. This result shows that GRAM is essential for proper protein association with its target membrane. In contrast, deletion of the catalytic domain did not impair protein localization, but abolished pexophagy, suggesting that SG synthesis is required for this process.

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

  • A Glucosyltransferase specific for 4-hydroxy-2,5-dimethyl-3(2H)-furanone in strawberry
    2018
    Co-Authors: Aki Yamada, Kan’ichiro Ishiuchi, Toshiaki Makino, Hajime Mizukami, Kazuyoshi Terasaka
    Abstract:

    4-Hydroxy-2,5-dimethyl-3(2H)-furanone (HDMF) is a key aroma compound in Fragaria × ananassa (strawberry). A considerable amount of HDMF is converted into HDMF β-D-glucoside and accumulated in mature strawberry fruits. Here we isolated a novel UDP-glucose: HDMF Glucosyltransferase, UGT85K16 from Fragaria × ananassa. UGT85K16 preferentially glucosylated the hydroxyl group of HDMF and its structural analogs. Although UGT85K16 also catalyzed the glucosylation of vanillin, its affinity and efficiency toward HDMF was higher. The expression of UGT85K16 mRNA correlated with the accumulation of HDMF and its glucoside in Fragaria × ananassa plants. These results suggest that UGT85K16 might be UDP-glucose: HDMF Glucosyltransferase in strawberries. Abbreviations: DMMF: 2,5-dimethyl-4-methoxy-3(2H)-furanone; EHMF: 2(5)-ethyl-4-hydroxy-5(2)-methyl-3(2H)-furanone; GBV: glycosidically bound volatile; HDMF: 4-hydroxy-2,5-dimethyl-3(2H)-furanone; HMF: 4-hydroxy-5-methyl-3(2H)-furanone; HMMF: 4-hydroxy-5-methyl-2-methylene-3(2H)-furanone; PSPG: Plant secondary product glycosyltransferase; RT-PCR: reverse transcription-PCR; OMT: O-methyltransferase; UGT: UDP-glycosyltransferase Characterization of HDMF Glucosyltransferase (UGT85K16) from strawberry.

  • Identification and functional analysis of 2-hydroxyflavanone C-Glucosyltransferase in soybean (Glycine max).
    FEBS letters, 2015
    Co-Authors: Yoshihiro Hirade, Kazuyoshi Terasaka, Naoyuki Kotoku, Yumiko Saijo-hamano, Akemi Fukumoto, Hajime Mizukami
    Abstract:

    C-Glucosyltransferase is an enzyme that mediates carbon–carbon bond formation to generate C-glucoside metabolites. Although it has been identified in several plant species, the catalytic amino acid residues required for C-glucosylation activity remain obscure. Here, we identified a 2-hydroxyflavanone C-Glucosyltransferase (UGT708D1) in soybean. We found that three residues, His20, Asp85, and Arg292, of UGT708D1 were located at the predicted active site and evolutionarily conserved. The substitution of Asp85 or Arg292 with alanine destroyed C-Glucosyltransferase activity, whereas the substitution of His20 with alanine abolished C-Glucosyltransferase activity but enabled O-Glucosyltransferase activity. The catalytic mechanism is discussed on the basis of the findings.

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

Patrik R Jones - One of the best experts on this subject based on the ideXlab platform.

  • ugt73c6 and ugt78d1 glycosyltransferases involved in flavonol glycoside biosynthesis in arabidopsis thaliana
    Journal of Biological Chemistry, 2003
    Co-Authors: Patrik R Jones, Burkhard Messner, Junichiro Nakajima, Anton R Schaffner, Kazuki Saito
    Abstract:

    Abstract Flavonol glycosides constitute one of the most prominent plant natural product classes that accumulate in the model plant Arabidopsis thaliana. To date there are no reports of functionally characterized flavonoid glycosyltransferases in Arabidopsis, despite intensive research efforts aimed at both flavonoids and Arabidopsis. In this study, flavonol glycosyltransferases were considered in a functional genomics approach aimed at revealing genes involved in determining the flavonol-glycoside profile. Candidate glycosyltransferase-encoding genes were selected based on homology to other known flavonoid glycosyltransferases and two T-DNA knockout lines lacking flavonol-3-O-rhamnoside-7-O-rhamnosides (ugt78D1) and quercetin-3-O-rhamnoside-7-O-glucoside (ugt73C6 and ugt78D1) were identified. To confirm the in planta results, cDNAs encoding both UGT78D1 and UGT73C6 were expressed in vitro and analyzed for their qualitative substrate specificity. UGT78D1 catalyzed the transfer of rhamnose from UDP-rhamnose to the 3-OH position of quercetin and kaempferol, whereas UGT73C6 catalyzed the transfer of glucose from UDP-glucose to the 7-OH position of kaempferol-3-O-rhamnoside and quercetin-3-O-rhamnoside, respectively. The present results suggest that UGT78D1 and UGT73C6 should be classified as UDP-rhamnose:flavonol-3-Orhamnosyltransferase and UDP-glucose:flavonol-3-O-glycoside-7-O-Glucosyltransferase, respectively.

  • the udp glucose p hydroxymandelonitrile o Glucosyltransferase that catalyzes the last step in synthesis of the cyanogenic glucoside dhurrin in sorghum bicolor isolation cloning heterologous expression and substrate specificity
    Journal of Biological Chemistry, 1999
    Co-Authors: Patrik R Jones, Birger Lindberg Moller
    Abstract:

    Abstract The final step in the biosynthesis of the cyanogenic glucoside dhurrin in Sorghum bicolor is the transformation of the labile cyanohydrin into a stable storage form byO-glucosylation of (S)-p-hydroxymandelonitrile at the cyanohydrin function. The UDP-glucose:p-hydroxymandelonitrile-O-Glucosyltransferase was isolated from etiolated seedlings of S. bicoloremploying Reactive Yellow 3 chromatography with UDP-glucose elution as the critical step. Amino acid sequencing allowed the cloning of a full-length cDNA encoding the Glucosyltransferase. Among the few characterized Glucosyltransferases, the deduced translation product showed highest overall identity to Zea maysflavonoid-Glucosyltransferase (Bz-Mc-2 allele). The substrate specificity of the enzyme was established using isolated recombinant protein. Compared with endogenousp-hydroxymandelonitrile, mandelonitrile, benzyl alcohol, and benzoic acid were utilized at maximum rates of 78, 13, and 4%, respectively. Surprisingly, the monoterpenoid geraniol was glucosylated at a maximum rate of 11% compared withp-hydroxymandelonitrile. The picture that is emerging regarding plant Glucosyltransferase substrate specificity is one of limited but extended plasticity toward metabolites of related structure. This in turn ensures that a relatively high, but finite, number of Glucosyltransferases can give rise to the large number of glucosides found in plants.