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1.
Dae Gyun An So Mi Yang Bong Gyu Kim Joong-Hoon Ahn 《Journal of industrial microbiology & biotechnology》2016,43(6):841-849
Various flavonoid glycosides are found in nature, and their biological activities are as variable as their number. In some cases, the sugar moiety attached to the flavonoid modulates its biological activities. Flavonoid glycones are not easily synthesized chemically. Therefore, in this study, we attempted to synthesize quercetin 3-O-glucosyl (1→2) xyloside and quercetin 3-O-glucosyl (1→6) rhamnoside (also called rutin) using two uridine diphosphate-dependent glycosyltransferases (UGTs) in Escherichia coli. To synthesize quercetin 3-O-glucosyl (1→2) xyloside, sequential glycosylation was carried out by regulating the expression time of the two UGTs. AtUGT78D2 was subcloned into a vector controlled by a Tac promoter without a lacI operator, while AtUGT79B1 was subcloned into a vector controlled by a T7 promoter. UDP-xyloside was supplied by concomitantly expressing UDP-glucose dehydrogenase (ugd) and UDP-xyloside synthase (UXS) in the E. coli. Using these strategies, 65.0 mg/L of quercetin 3-O-glucosyl (1→2) xyloside was produced. For the synthesis of rutin, one UGT (BcGT1) was integrated into the E. coli chromosome and the other UGT (Fg2) was expressed in a plasmid along with RHM2 (rhamnose synthase gene 2). After optimization of the initial cell concentration and incubation temperature, 119.8 mg/L of rutin was produced. The strategies used in this study thus show promise for the synthesis of flavonoid diglucosides in E. coli. 相似文献
2.
Hyeon Jeong Kim Bong-Gyu Kim Joong-Hoon Ahn 《Applied microbiology and biotechnology》2013,97(12):5275-5282
Regioselective glycosylation of flavonoids cannot be easily achieved due to the presence of several hydroxyl groups in flavonoids. This hurdle could be overcome by employing uridine diphosphate-dependent glycosyltransferases (UGTs), which use nucleotide sugars as sugar donors and diverse compounds including flavonoids as sugar acceptors. Quercetin rhamnosides contain antiviral activity. Two quercetin diglycosides, quercetin 3-O-glucoside-7-O-rhamnoside and quercetin 3,7-O-bisrhamnoside, were synthesized using Escherichia coli expressing two UGTs. For the synthesis of quercetin 3-O-glucoside-7-O-rhamnoside, AtUGT78D2, which transfers glucose from UDP-glucose to the 3-hydroxyl group of quercetin, and AtUGT89C1, which transfers rhamnose from UDP-rhamnose to the 7-hydroxyl group of quercetin 3-O-glucoside, were transformed into E. coli. Using this approach, 67 mg/L of quercetin 3-O-glucoside-7-O-rhamnoside was synthesized. For the synthesis of quercetin 3,7-O-bisrhamnoside, AtUGT78D1, which transfers rhamnose to the 3-hydroxy group of quercetin, and AtUGT89C1 were used. The RHM2 gene from Arabidopsis thaliana was coexpressed to supply the sugar donor, UDP-rhamnose. E. coli expressing AtUGT78D1, AtUGT89C1, and RHM2 was used to obtain 67.4 mg/L of quercetin 3,7-O-bisrhamnoside. 相似文献
3.
Ozaki S Imai H Iwakiri T Sato T Shimoda K Nakayama T Hamada H 《Biotechnology letters》2012,34(3):475-481
A glucosyltransferase (GT) of Phytolacca americana (PaGT3) was expressed in Escherichia coli and purified for the synthesis of two O-β-glucoside products of trans-resveratrol. The reaction was moderately regioselective with a ratio of 4′-O-β-glucoside: 3-O-β-glucoside at 10:3. We used not only the purified enzyme but also the E. coli cells containing the PaGT3 gene for the synthesis of glycoconjugates. E. coli cell cultures also have other advantages, such as a shorter incubation time compared with cultured plant cells, no need for
the addition of exogenous glucosyl donor compounds such as UDP-glucose, and almost complete conversion of the aglycone to
the glucoside products. Furthermore, a homology model of PaGT3 and mutagenesis studies suggested that His-20 would be a catalytically
important residue. 相似文献
4.
Dinesh Simkhada Nagendra Prasad Kurumbang Hei Chan Lee Jae Kyung Sohng 《Biotechnology and Bioprocess Engineering》2010,15(5):754-760
Flavonoids glycosylated with UDP-glucuronic acid and UDP-xylose are spatially distributed in nature. To produce these glycosides,
E. coli was engineered to overexpress biosynthetic gene clusters of UDP-sugars (galU from E. coli K12, UDP-glucose dehydrogenase (calS8), and UDP-glucuronic acid decarboxylase (calS9) from Micromonospora echinospora spp. calichensis). Flavonoids were glycosylated by overexpression of the glycosyltransferase gene (atGt-5) from Arabidopsis thaliana. Finally, metabolically engineered host E. coli (US89Gt-5) was generated. Production of flavonoid glycosides was observed in a biotransformation system consisting of flavonoids
(naringenin and quercetin) exogenously fed to host cells. The glycosylated derivatives 7-O-glucuronyl naringenin (m/z+ 449), 7-O-xylosyl naringenin (m/z+ 405), and 7-O-glucuronyl quercetin (m/z+ 479) were detected and confirmed by ESI-MS/MS, ESI-MS/MS and LC/MS-MS analysis, respectively. 相似文献
5.
We isolated several mutants of Arabidopsis thaliana (L.) Heynh. that accumulated less anthocyanin in the plant tissues, but had seeds with a brown color similar to the wild-type.
These mutants were allelic with the anthocyaninless1 (anl1) mutant that has been mapped at 15.0 cM of chromosome 5. We performed fine mapping of the anl1 locus and determined that ANL1 is located between the nga106 marker and a marker corresponding to the MKP11 clone. About 70 genes are located between these
two markers, including three UDP-glucose:flavonoid-3-O-glucosyltransferase-like genes and a glutathione transferase gene (TT19). A mutant of one of the glucosyltransferase genes (At5g17050) was unable to complement the anl1 phenotype, showing that the ANL1 gene encodes UDP-glucose:flavonoid-3-O-glucosyltransferase. ANL1 was expressed in all tissues examined, including rosette leaves, stems, flower buds and roots. ANL1 was not regulated by TTG1. 相似文献
6.
Buriev ZT Saha S Shermatov SE Jenkins JN Abdukarimov A Stelly DM Abdurakhmonov IY 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2011,123(8):1359-1373
The Gossypium MIC-3 (Meloidogyne Induced Cotton-3) gene family is of great interest for molecular evolutionary studies because of its uniqueness to Gossypium species, multi-gene content, clustered localization, and root-knot nematode resistance-associated features. Molecular evolution
of the MIC-3 gene family was studied in 15 tetraploid and diploid Gossypium genotypes that collectively represent seven phylogenetically distinct genomes. Synonymous (dS) and non-synonymous (dN) nucleotide substitution rates suggest that the second of the two exons of the MIC-3 genes has been under strong positive selection pressure, while the first exon has been under strong purifying selection to
preserve function. Based on nucleotide substitution rates, we conclude that MIC-3 genes are evolving by a birth-and-death process and that a ‘gene amplification’ mechanism has helped to retain all duplicate
copies, which best fits with the “bait and switch” model of R-gene evolution. The data indicate MIC-3 gene duplication events occurred at various rates, once per 1 million years (MY) in the allotetraploids, once per ~2 MY in
the A/F genome clade, and once per ~8 MY in the D-genome clade. Variations in the MIC-3 gene family seem to reflect evolutionary selection for increased functional stability, while also expanding the capacity
to develop novel “switch” pockets for responding to diverse pests and pathogens. Such evolutionary roles are congruent with
the hypothesis that members of this unique resistance gene family provide fitness advantages in Gossypium. 相似文献
7.
Young-Cheon Kim Namrata D. Udeshi Jeremy L. Balsbaugh Jeffrey Shabanowitz Donald F. Hunt Neil E. Olszewski 《Amino acids》2011,40(3):869-876
The capsid protein of Plum pox virus (PPV-CP) is modified with O-linked β-N-acetylglucosamine (O-GlcNAc). In Arabidopsis thaliana this modification is made by an O-GlcNAc transferase named SECRET AGENT (SEC). Modification of PPV-CP by SEC is hypothesized to have a direct role in the infection
process, because virus titer and rate of spread are reduced in SEC mutants. Previous studies used deletion mapping and site-directed
mutagenesis to identify four O-GlcNAc sites on the capsid protein that are modified by Escherichia coli-expressed SEC. The infection process was not affected when two of these sites were mutated suggesting that O-GlcNAcylation of these sites does not have a significant role in the infection process or that a subset of the modifications
is sufficient. Since it is possible that the mutational mapping approach missed or incorrectly identified O-GlcNAc sites, the modifications produced by E. coli-expressed SEC were characterized using mass spectrometry. O-GlcNAcylated peptides were enzymatically tagged with galactose, the products were enriched on immobilized Ricinus communis agglutinin I and sequenced by electron transfer dissociation (ETD) mass spectrometry. Five O-GlcNAc sites on PPV-CP were identified. Two of these sites were not identified in by the previous mutational mapping. In
addition, one site previously predicted by mutation mapping was not detected, but modification of this site was not supported
when the mutation mapping was repeated. This study suggests that mapping modification sites by ETD mass spectrometry is more
comprehensive and accurate than mutational mapping. 相似文献
8.
A-Rang Im Youmie Park Joon-Soo Sim Zhenqing Zhang Zhenling Liu Robert J. Linhardt Yeong Shik Kim 《Glycoconjugate journal》2010,27(2):249-257
The whole tissue of the earthworm (Eisenia andrei) was lyophilized and extracted to purify glycosaminoglycans. Fractions, eluting from an anion-exchange column at 1.0 M and
2.0 M NaCl, showed the presence of acidic polysaccharides on agarose gel electrophoresis. Monosaccharide compositional analysis
showed that galactose and glucose were most abundant monosaccharides in both fractions. Depolymerization of the polysaccharide
mixture with glycosaminoglycan-degrading enzymes confirmed the presence of chondroitin sulfate/dermatan sulfate and heparan
sulfate in the 2.0 M NaCl fraction. The content of GAGs (uronic acid containing polysaccharide) in the 2.0 M NaCl fraction
determined by carbazole assay was 2%. Disaccharide compositional analysis using liquid chromatography–electrospray ionization
mass spectrometry (LC–ESI–MS) analysis after chondroitinase digestion (ABC and ACII), showed that the chondroitin sulfate/dermatan
sulfate contained a 4-O-sulfo (76%), 2,4-di-O-sulfo (15%), 6-O-sulfo (6%), and unsulfated (4%) uronic acid linked N-acetylgalactosamine residues. LC–ESI–MS analysis of heparin lyase I/II/III digests demonstrated the presence of N-sulfo (69%), N-sulfo-6-O-sulfo (25%) and 2-O-sulfo-N-sulfo-6-O-sulfo (5%) uronic acid linked N-acetylglucosamine residues. 相似文献
9.
V. N. Verbenko L. V. Kuznetsova E. P. Krupyan V. I. Shalguev 《Russian Journal of Genetics》2009,45(10):1192-1199
Plasmids pKS5 and pKSrec30 carrying normal and mutant alleles of the Deinococcus recA gene controlled by the lactose promoter slightly increase radioresistance of Escherichia coli cells with mutations in genes recA and ssb. The RecA protein of D. radiodurans is expressed in E. coli cells, and its synthesis can be supplementary induced. The radioprotective effect of the xenologic protein does not exceed
1.5 fold and yields essentially to the contribution of plasmid pUC19-recA1.1 harboring the E. coli recA
+ gene in the recovery of resistance of the ΔrecA deletion mutant. These data suggest that the expression of D. radiodurans recA gene in E. coli cells does not complement mutations at gene recA in the chromosome possibly due to structural and functional peculiarities of the D. radiodurans RecA protein. 相似文献
10.
11.
Himi E Maekawa M Miura H Noda K 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2011,122(8):1561-1576
The grain color of wheat affects not only the brightness of flour, but also tolerance to preharvest sprouting. Grain color
is controlled by dominant R-1 genes located on the long arm of hexaploid wheat chromosomes 3A, 3B, and 3D (R-A1, R-B1, and R-D1, respectively). The red pigment of the grain coat is composed of catechin and proanthocyanidin (PA), which are synthesized
via the flavonoid biosynthetic pathway. We isolated the Tamyb10-A1, Tamyb10-B1, and Tamyb10-D1 genes, located on chromosomes 3A, 3B, and 3D, respectively. These genes encode R2R3-type MYB domain proteins, similar to
TT2 of Arabidopsis, which controls PA synthesis in testa. In recessive R-A1 lines, two types of Tamyb10-A1 genes: (1) deletion of the first half of the R2-repeat of the MYB region and (2) insertion of a 2.2-kb transposon belonging
to the hAT family. The Tamyb10-B1 genes of recessive R-B1 lines had 19-bp deletion, which caused a frame shift in the middle part of the open reading frame. With a transient assay
using wheat coleoptiles, we revealed that the Tamyb10 gene in the dominant R-1 allele activated the flavonoid biosynthetic genes. We developed PCR-based markers to detect the dominant/recessive alleles
of R-A1, R-B1, and R-D1. These markers proved to be correlated to known R-1 genotypes of 33 varieties except for a mutant with a single nucleotide substitution. Furthermore, double-haploid (DH) lines
derived from the cross between red- and white-grained lines were found to necessarily carry functional Tamyb10 gene(s). Thus, PCR-based markers for Tamyb10 genes are very useful to detect R-1 alleles. 相似文献
12.
Foley S Stolarczyk E Mouni F Brassart C Vidal O Aïssi E Bouquelet S Krzewinski F 《Archives of microbiology》2008,189(2):157-167
Bifidobacterium bifidum, in contrast to other bifidobacterial species, is auxotrophic for N-acetylglucosamine. Growth experiments revealed assimilation of radiolabelled N-acetylglucosamine in bacterial cell walls and in acetate, an end-product of central metabolism via the bifidobacterial d-fructose-6-phosphate shunt. While supplementation with fructose led to reduced N-acetylglucosamine assimilation via the d-fructose-6-phosphate shunt, no significant difference was observed in levels of radiolabelled N-acetylglucosamine incorporated into cell walls. Considering the central role played by glutamine fructose-6-phosphate transaminase
(GlmS) in linking the biosynthetic pathway for N-acetylglucosamine to hexose metabolism, the GlmS of Bifidobacterium was characterized. The genes encoding the putative GlmS of B. longum DSM20219 and B. bifidum DSM20082 were cloned and sequenced. Bioinformatic analyses of the predicted proteins revealed 43% amino acid identity with
the Escherichia coli GlmS, with conservation of key amino acids in the catalytic domain. The B. longum GlmS was over-produced as a histidine-tagged fusion protein. The purified C-terminal His-tagged GlmS possessed glutamine
fructose-6-phosphate amidotransferase activity as demonstrated by synthesis of glucosamine-6-phosphate from fructose-6-phosphate
and glutamine. It also possesses an independent glutaminase activity, converting glutamine to glutamate in the absence of
fructose-6-phosphate. This is of interest considering the apparently reduced coding potential in bifidobacteria for enzymes
associated with glutamine metabolism.
S. Foley and E. Stolarczyk contributed equally to this work 相似文献
13.
Cigang Yu Haidong Xu Guodong Huang Ting Chen Guiyou Liu Nan Chai Yin Ji Siyuan Wang Yijun Dai Sheng Yuan 《Applied microbiology and biotechnology》2010,86(3):863-870
The main product of the conversion of puerarin by unpermeabilized cells of bacterium Microbacterium oxydans CGMCC 1788 was puerarin-7-O-glucoside (241 ± 31.9 μM). Permeabilization with 40% ethanol could not increase conversion yield, whereas it resulted in
change of main product; a previous trace product became a main product (213 ± 48.0 μM) which was identified as a novel puerarin-7-O-fructoside by electrospray ionization time-of-flight MS, 13C NMR, 1H NMR, and GC-MS analysis of sugar composition, and puerarin-7-O-glucoside became a trace product (14.8 ± 5.4 μM). However, the extract from cells of M. oxydans CGMCC 1788 permeabilized with ethanol converted puerarin to form 113.9 ± 27.7 μM puerarin-7-O-glucoside and 187.8 ± 29.5 μM puerarin-7-O-fructoside under the same conditions. When unpermeabilized intact cells were recovered and used repeatedly for the conversion
of puerarin, with increase of reuse times, the yield of puerarin-7-O-glucoside gradually decreased, whereas the yield of puerarin-7-O-fructoside increased gradually in the conversion mixture. The main product of the conversion of puerarin by the tenth recycled
unpremerbilized cells was puerarin-7-O-fructoside (288.4 ± 24.0 μM). Therefore, the change of permeability of cell membrane of bacterium M. oxydans CGMCC 1788 contributed to the change of conversion of the product’s composition. 相似文献
14.
Sanath Kumar Ammini Parvathi Ricardo L. Hernandez Kathleen M. Cadle Manuel F. Varela 《Archives of microbiology》2009,191(5):425-429
MurA [UDP-N-acetylglucosamine (UDP-NAG) enolpyruvyl transferase] is a key enzyme involved in bacterial cell wall peptidoglycan synthesis
and a target for the antimicrobial agent fosfomycin, a structural analog of the MurA substrate phosphoenol pyruvate. In this
study, we identified, cloned and sequenced a novel murA gene from an environmental isolate of Vibrio fischeri that is naturally resistant to fosfomycin. The fosfomycin resistance gene was isolated from a genomic DNA library of V. fischeri. An antimicrobial agent hypersensitive strain of Escherichia coli harboring murA from V. fischeri exhibited a high fosfomycin resistance phenotype, with minimum inhibitory concentration of 3,000 μg/ml. The cloned murA gene was 1,269 bp long encoding a 422 amino acid polypeptide with an estimated pI of 5.0. The deduced amino acid sequence
of the putative protein was identified as UDP-NAG enolpyruvyl transferase by homology comparison. The MurA protein with an
estimated molecular weight of 44.7 kDa was expressed in E. coli and purified by affinity chromatography. MurA of V. fischeri will be a useful target to identify potential inhibitors of fosfomycin resistance in pharmacological studies. 相似文献
15.
A cDNA encoding UDP-glucose: formononetin 7-O-glucosyltransferase, designated UGT73F1, was cloned from yeast extract-treated Glycyrrhiza echinata L. cell-suspension cultures using probes from Scutellaria baicalensis UDP-glucose: flavonoid 7-O-glucosyltransferase. The open reading frame of the UGT73F1 cDNA encodes a 441-amino-acid protein with a predicted molecular mass of 48.7 kDa. The deduced amino acid sequence showed that the protein is related to the stress-inducible glucosyltransferases. UGT73F1 mRNA was not detected in untreated G. echinata cultures but was transiently induced by treatment with yeast extract. Recombinant UGT73F1 was expressed as a histidine-tag fusion protein in Escherichia coli and purified to near homogeneity by nickel chelate chromatography. The purified recombinant enzyme was selective for isoflavonoid, formononetin and daidzein as substrates, while flavonoids and various tested non-flavonoid compounds were poor substrates.Abbreviations GT
UDP-glycosyltransferase
- rUGT73F1
recombinant UGT73F1
- UBGT: UDP-glucose:
baicalein 7-O-glucosyltransferase
The nucleotide sequence data reported in this paper will appear in the DDBJ/EMBL/GenBank nucleotide sequence databases with the accession number AB098614. 相似文献
16.
Yoon SH Kim JE Lee SH Park HM Choi MS Kim JY Lee SH Shin YC Keasling JD Kim SW 《Applied microbiology and biotechnology》2007,74(1):131-139
The lycopene synthetic pathway was engineered in Escherichia coli using the carotenoid genes (crtE, crtB, and crtI) of Pantoea agglomerans and Pantoea ananatis. E. coli harboring the P. agglomerans crt genes produced 27 mg/l of lycopene in 2YT medium without isopropyl-beta-d-thiogalactopyranoside (IPTG) induction, which was twofold higher than that produced by E. coli harboring the P. ananatis crt genes (12 mg/l lycopene) with 0.1 mM IPTG induction. The crt genes of P. agglomerans proved better for lycopene production in E. coli than those of P. ananatis. The crt genes of the two bacteria were also compared in E. coli harboring the mevalonate bottom pathway, which was capable of providing sufficient carotenoid building blocks, isopentenyl
diphosphate (IPP) and dimethylallyl diphosphate (DMAPP), with exogenous mevalonate supplementation. Lycopene production significantly
increased using the mevalonate bottom pathway and 60 mg/l of lycopene was obtained with the P. agglomerans crt genes, which was higher than that obtained with the P. ananatis crt genes (35 mg/l lycopene). When crtE among the P. ananatis crt genes was replaced with P. agglomerans crtE or Archaeoglobus fulgidus gps, both lycopene production and cell growth were similar to that obtained with P. agglomerans
crt genes. The crtE gene was responsible for the observed difference in lycopene production and cell growth between E. coli harboring the crt genes of P. agglomerans and P. ananatis. As there was no significant difference in lycopene production between E. coli harboring P. agglomerans
crtE and A. fulgidus gps, farnesyl diphosphate (FPP) synthesis was not rate-limiting in E. coli.
Sang-Hwal Yoon and Ju-Eun Kim: These authors contributed equally to this work. 相似文献
17.
A biotransformation system was designed to co-express CYP107P3 (CSP4), cytochrome P450, from Streptomyces peuceticus, along with CamA (putidaredoxin reductase) and CamB (putidaredoxin) from Pseudomonas putida, the necessary reducing equivalents, in a class I type electron-transfer system in E. coli BL21 (DE3). This was carried out using two plasmids with different selection markers and compatible origins of replication.
The study results showed that this biotransformation system was able to mediate the O-dealkylation of 7-ethoxycumarin. 相似文献
18.
Toluene dioxygenase (TDO) catalyzes asymmetric cis-dihydroxylation of aromatic compounds. To achieve high efficient biotransformation of benzene to benzene cis-diols, Pseudomonas putida KT2442, Pseudomonas stutzeri 1317, and Aeromonas hydrophila 4AK4 were used as hosts to express TDO gene tod. Plasmid pSPM01, a derivative of broad-host plasmid pBBR1MCS-2 harboring tod from plasmid pKST11, was constructed and introduced into the above three strains. Their abilities to catalyze the biotransformation
of benzene to benzene cis-diols, namely, cis-3,5-cyclohexadien-1,2-diols abbreviated as DHCD, were examined. In shake-flask cultivation under optimized culture media
and growth condition, benzene cis-diols production by recombinant P. putida KT2442 (pSPM01), P. stutzeri 1317 (pSPM01), and A. hydrophila 4AK4 (pSPM01) were 2.68, 2.13, and 1.17 g/l, respectively. In comparison, Escherichia coli JM109 (pSPM01) and E. coli JM109 (pKST11) produced 0.45 and 0.53 g/l of DHCD, respectively. When biotransformation was run in a 6-l fermenter, DHCD
production in P. putida KT2442 (pSPM01) was approximately 60 g/l; this is the highest DHCD production yield reported so far. 相似文献
19.
Bioconversion of quercetin glucosides using four generally recognized as safe (GRAS) organisms (Aspergillus oryzae, Bacillus subtilis, Lactobacillus plantarum, and Saccharomyces cerevisiae) was evaluated by measuring changes in the levels of quercetin compounds of onion. Of the four organisms, S. cerevisiae increased the content of quercetin-3-O-β-d-glucoside (III; isoquercitrin) and quercetin (IV), whereas decreasing quercetin-3,4′-O-β-d-glucoside (I) and quercetin-4′-O-β-d-glucoside (II). Also, S. cerevisiae converted authentic compound I to III, and II to IV, respectively. These results suggest that S. cerevisiae can be used to increase the levels of isoquercitrin (III), the most bioavailable quercetin compound in onion. 相似文献
20.
Bong-Gyu Kim Na Yeon Kim Jeong Ho Kim Kazuya Akimitsu Youhoon Chong Joong-Hoon Ahn 《Journal of Plant Biology》2009,52(1):41-48
Among more than 100 rice uridine diphosphate glycosyltransferases (UGTs), OsUGT-3 was selected as a candidate for producing flavonoid O-diglycosyltransferases based on phylogenetic analysis and molecular docking. This gene was functionally expressed in Escherichia coli. Analysis of kaempferol, luteolin, quercetin, and tricin reaction products using liquid chromatography-mass spectrometry revealed
that these were diglucosylated. The glucosylation positions of kaempferol, which was the best substrate, were determined to
be the 3- and 7-hydroxyl groups. This is the first flavonoid O-diglucosyltransferase described from rice. 相似文献