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Li C, Zhang Y. Glycosylation and methylation in the biosynthesis of isoflavonoids in Pueraria lobata. FRONTIERS IN PLANT SCIENCE 2023; 14:1330586. [PMID: 38162309 PMCID: PMC10757850 DOI: 10.3389/fpls.2023.1330586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Accepted: 12/01/2023] [Indexed: 01/03/2024]
Abstract
The pathway for forming isoflavonoid skeletal structure is primarily restricted to the Leguminosae family. Subsequent decorations on the compound backbone by tailoring enzymes would change their biological and medicinal properties. Pueraria lobata is a leguminous plant, and as a traditional Chinese medicine its roots have been ascribed a number of pharmacological activities. Glycosylation and methylation are the main modifying processes in isoflavonoid metabolism in P. lobata roots, resulting in the accumulation of unique glycosylated and methylated end isoflavonoid compounds. For instance, daidzein 8-C-glucoside (i.e., puerarin) and puerarin derivatives are produced only by the Pueraria genus. Puerarin has been established as a clinical drug for curing cardiovascular diseases. To better understand the characteristic isoflavonoid metabolism in P. lobata, this review attempts to summarize the research progress made with understanding the main glycosylation and methylation of isoflavonoids in P. lobata and their biosynthetic enzymes.
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Affiliation(s)
| | - Yansheng Zhang
- Shanghai Key Laboratory of Bio-Energy Crops, School of Life Sciences, Shanghai University, Shanghai, China
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2
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Adolfo LM, Burks D, Rao X, Alvarez‐Hernandez A, Dixon RA. Evaluation of pathways to the C-glycosyl isoflavone puerarin in roots of kudzu ( Pueraria montana lobata). PLANT DIRECT 2022; 6:e442. [PMID: 36091880 PMCID: PMC9438399 DOI: 10.1002/pld3.442] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Revised: 07/21/2022] [Accepted: 08/05/2022] [Indexed: 06/15/2023]
Abstract
Kudzu (Pueraria montana lobata) is used as a traditional medicine in China and Southeast Asia but is a noxious weed in the Southeastern United States. It produces both O- and C-glycosylated isoflavones, with puerarin (C-glucosyl daidzein) as an important bioactive compound. Currently, the stage of the isoflavone pathway at which the C-glycosyl unit is added remains unclear, with a recent report of direct C-glycosylation of daidzein contradicting earlier labeling studies supporting C-glycosylation at the level of chalcone. We have employed comparative mRNA sequencing of the roots from two Pueraria species, one of which produces puerarin (field collected P. montana lobata) and one of which does not (commercial Pueraria phaseoloides), to identify candidate uridine diphosphate glycosyltransferase (UGT) enzymes involved in puerarin biosynthesis. Expression of recombinant UGTs in Escherichia coli and candidate C-glycosyltransferases in Medicago truncatula were used to explore substrate specificities, and gene silencing of UGT and key isoflavone biosynthetic genes in kudzu hairy roots employed to test hypotheses concerning the substrate(s) for C-glycosylation. Our results confirm UGT71T5 as a C-glycosyltransferase of isoflavone biosynthesis in kudzu. Enzymatic, isotope labeling, and genetic analyses suggest that puerarin arises both from the direct action of UGT71T5 on daidzein and via a second route in which the C-glycosidic linkage is introduced to the chalcone isoliquiritigenin.
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Affiliation(s)
- Laci M. Adolfo
- BioDiscovery Institute and Department of Biological SciencesUniversity of North TexasDentonTexasUSA
| | - David Burks
- BioDiscovery Institute and Department of Biological SciencesUniversity of North TexasDentonTexasUSA
| | - Xiaolan Rao
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life SciencesHubei UniversityWuhanHubei ProvinceChina
| | | | - Richard A. Dixon
- BioDiscovery Institute and Department of Biological SciencesUniversity of North TexasDentonTexasUSA
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3
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Tay KC, Tan LTH, Chan CK, Hong SL, Chan KG, Yap WH, Pusparajah P, Lee LH, Goh BH. Formononetin: A Review of Its Anticancer Potentials and Mechanisms. Front Pharmacol 2019; 10:820. [PMID: 31402861 PMCID: PMC6676344 DOI: 10.3389/fphar.2019.00820] [Citation(s) in RCA: 147] [Impact Index Per Article: 29.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Accepted: 06/24/2019] [Indexed: 12/24/2022] Open
Abstract
Cancer, a complex yet common disease, is caused by uncontrolled cell division and abnormal cell growth due to a variety of gene mutations. Seeking effective treatments for cancer is a major research focus, as the incidence of cancer is on the rise and drug resistance to existing anti-cancer drugs is major concern. Natural products have the potential to yield unique molecules and combinations of substances that may be effective against cancer with relatively low toxicity/better side effect profile compared to standard anticancer therapy. Drug discovery work with natural products has demonstrated that natural compounds display a wide range of biological activities correlating to anticancer effects. In this review, we discuss formononetin (C16H12O4), which originates mainly from red clovers and the Chinese herb Astragalus membranaceus. The compound comes from a class of 7-hydroisoflavones with a substitution of methoxy group at position 4. Formononetin elicits antitumorigenic properties in vitro and in vivo by modulating numerous signaling pathways to induce cell apoptosis (by intrinsic pathway involving Bax, Bcl-2, and caspase-3 proteins) and cell cycle arrest (by regulating mediators like cyclin A, cyclin B1, and cyclin D1), suppress cell proliferation [by signal transducer and activator of transcription (STAT) activation, phosphatidylinositol 3-kinase/protein kinase-B (PI3K/AKT), and mitogen-activated protein kinase (MAPK) signaling pathway], and inhibit cell invasion [by regulating growth factors vascular endothelial growth factor (VEGF) and Fibroblast growth factor 2 (FGF2), and matrix metalloproteinase (MMP)-2 and MMP-9 proteins]. Co-treatment with other chemotherapy drugs such as bortezomib, LY2940002, U0126, sunitinib, epirubicin, doxorubicin, temozolomide, and metformin enhances the anticancer potential of both formononetin and the respective drugs through synergistic effect. Compiling the evidence thus far highlights the potential of formononetin to be a promising candidate for chemoprevention and chemotherapy.
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Affiliation(s)
- Kai-Ching Tay
- Biofunctional Molecule Exploratory (BMEX) Research Group, School of Pharmacy, Monash University Malaysia, Bandar Sunway, Malaysia
| | - Loh Teng-Hern Tan
- Novel Bacteria and Drug Discovery (NBDD) Research Group, Microbiome and Bioresource Research Strength Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, Bandar Sunway, Malaysia.,Institute of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou, China
| | | | - Sok Lai Hong
- Centre for Research Services, Institute of Research Management and Services, University of Malaya, Kuala Lumpur, Malaysia
| | - Kok-Gan Chan
- Division of Genetics and Molecular Biology, Institute of Biological Sciences, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia.,International Genome Centre, Jiangsu University, Zhenjiang, China
| | - Wei Hsum Yap
- School of Biosciences, Taylor's University, Subang Jaya, Malaysia
| | - Priyia Pusparajah
- Medical Health and Translational Research Group (MHTR), Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, Bandar Sunway, Malaysia
| | - Learn-Han Lee
- Novel Bacteria and Drug Discovery (NBDD) Research Group, Microbiome and Bioresource Research Strength Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, Bandar Sunway, Malaysia.,Institute of Pharmaceutical Science, University of Veterinary and Animal Science, Lahore, Pakistan
| | - Bey-Hing Goh
- Biofunctional Molecule Exploratory (BMEX) Research Group, School of Pharmacy, Monash University Malaysia, Bandar Sunway, Malaysia.,Institute of Pharmaceutical Science, University of Veterinary and Animal Science, Lahore, Pakistan
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Pandey A, Misra P, Khan MP, Swarnkar G, Tewari MC, Bhambhani S, Trivedi R, Chattopadhyay N, Trivedi PK. Co-expression of Arabidopsis transcription factor, AtMYB12, and soybean isoflavone synthase, GmIFS1, genes in tobacco leads to enhanced biosynthesis of isoflavones and flavonols resulting in osteoprotective activity. PLANT BIOTECHNOLOGY JOURNAL 2014; 12:69-80. [PMID: 24102754 DOI: 10.1111/pbi.12118] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2013] [Accepted: 08/09/2013] [Indexed: 05/07/2023]
Abstract
Isoflavones, a group of flavonoids, restricted almost exclusively to family Leguminosae are known to exhibit anticancerous and anti-osteoporotic activities in animal systems and have been a target for metabolic engineering in commonly consumed food crops. Earlier efforts based on the expression of legume isoflavone synthase (IFS) genes in nonlegume plant species led to the limited success in terms of isoflavone content in transgenic tissue due to the limitation of substrate for IFS enzyme. In this work to overcome this limitation, the activation of multiple genes of flavonoid pathway using Arabidopsis transcription factor AtMYB12 has been carried out. We developed transgenic tobacco lines constitutively co-expressing AtMYB12 and GmIFS1 (soybean IFS) genes or independently and carried out their phytochemical and molecular analyses. The leaves of co-expressing transgenic lines were found to have elevated flavonol content along with the accumulation of substantial amount of genistein glycoconjugates being at the highest levels that could be engineered in tobacco leaves till date. Oestrogen-deficient (ovariectomized, Ovx) mice fed with leaf extract from transgenic plant co-expressing AtMYB12 and GmIFS1 but not wild-type extract exhibited significant conservation of trabecular microarchitecture, reduced osteoclast number and expression of osteoclastogenic genes, higher total serum antioxidant levels and increased uterine oestrogenicity compared with Ovx mice treated with vehicle (control). The skeletal effect of the transgenic extract was comparable to oestrogen-treated Ovx mice. Together, our results establish an efficient strategy for successful pathway engineering of isoflavones and other flavonoids in crop plants and provide a direct evidence of improved osteoprotective effect of transgenic plant extract.
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Affiliation(s)
- Ashutosh Pandey
- Council of Scientific and Industrial Research-National Botanical Research Institute, (CSIR-NBRI), Lucknow, India
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5
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He X, Blount JW, Ge S, Tang Y, Dixon RA. A genomic approach to isoflavone biosynthesis in kudzu (Pueraria lobata). PLANTA 2011; 233:843-55. [PMID: 21221632 DOI: 10.1007/s00425-010-1344-1] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2010] [Accepted: 12/22/2010] [Indexed: 05/18/2023]
Abstract
Roots of kudzu (Pueraria lobata) are a rich source of isoflavone O- and C-glycosides. Although O-glycosylation of (iso)flavonoids has been well characterized at the molecular level, no plant isoflavonoid C-glycosyltransferase genes have yet been isolated. To address the biosynthesis of kudzu isoflavonoids, we generated 6,365 high-quality expressed sequence tags (ESTs) from a subtraction cDNA library constructed using RNA from roots that differentially accumulate puerarin. The ESTs were clustered into 722 TCs and 3,913 singletons, from which 15 family I glycosyltransferases (UGTs) were identified. Hierarchical clustering analysis of the expression patterns of these UGTs with isoflavone synthase (IFS) in a range of tissues identified UGTs with potential functions in isoflavone glycosylation. The open reading frames of these UGTs were expressed in E. coli for functional analysis, and one was shown to preferentially glycosylate isoflavones at the 7-O-position. In addition, ESTs corresponding to chalcone synthase, chalcone reductase, chalcone isomerase (CHI) and 2-hydroxyisoflavanone dehydratase were identified. Recombinant CHI proteins had high activities with both 6'-deoxy- and 6'-hydroxy chalcones, typical of Type II CHIs. Establishment of this EST database and identification of genes associated with kudzu isoflavone biosynthesis and glycosylation provide a new resource for metabolic engineering of bioactive kudzu isoflavones.
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Affiliation(s)
- XianZhi He
- Plant Biology Division, Samuel Roberts Noble Foundation, 2510 Sam Noble Parkway, Ardmore, OK 73401, USA
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6
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Choi KY, Park HY, Kim BG. Characterization of bi-functional CYP154 from Nocardia farcinica IFM10152 in the O-dealkylation and ortho-hydroxylation of formononetin. Enzyme Microb Technol 2010. [DOI: 10.1016/j.enzmictec.2010.08.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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7
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Du H, Huang Y, Tang Y. Genetic and metabolic engineering of isoflavonoid biosynthesis. Appl Microbiol Biotechnol 2010; 86:1293-312. [DOI: 10.1007/s00253-010-2512-8] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2009] [Revised: 02/15/2010] [Accepted: 02/16/2010] [Indexed: 10/19/2022]
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8
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Choi KY, Kim TJ, Koh SK, Roh CH, Pandey BP, Lee N, Kim BG. A-ringortho-specific monohydroxylation of daidzein by cytochrome P450s ofNocardia farcinicaIFM10152. Biotechnol J 2009; 4:1586-95. [DOI: 10.1002/biot.200900157] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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9
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Abstract
Isoflavonoids are found predominantly in subfamily Papilionoideae of the Leguminosae. This review describes more than 420 new examples of Leguminosae isoflavonoids, giving details of their source, identification, biological activity, synthesis, and ecological or chemosystematic significance. Other topics addressed include the application of hyphenated analytical techniques to the characterisation of legume-derived isoflavonoids, and advances made in biosynthetic studies. A checklist of new compounds by species is given, and 404 references are cited.
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Affiliation(s)
- Nigel C Veitch
- Jodrell Laboratory, Royal Botanic Gardens, Kew, Richmond, Surrey, TW9 3AB, UK.
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Prasain JK, Reppert A, Jones K, Moore DR, Barnes S, Lila MA. Identification of isoflavone glycosides in Pueraria lobata cultures by tandem mass spectrometry. PHYTOCHEMICAL ANALYSIS : PCA 2007; 18:50-9. [PMID: 17260698 DOI: 10.1002/pca.951] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Isoflavones in the methanolic extracts of kudzu (Pueraria lobata) callus, suspension and root cultures were compared in order to develop an experimental system in which puerarin (daidzein 8-C-glucoside) and other isoflavones could be synthesised in vitro. Quantitative variation of puerarin and other known isoflavones was estimated in kudzu culture extracts using HPLC-UV. The highest and lowest amounts of puerarin (14.56 and 0.33 mg/g) were present in in vitro root cultures and leaf tissue-derived callus cultures, respectively. A total of 48 isoflavone metabolites were detected in extracts of kudzu root cultures by HPLC-MS/MS, and the structures of 33 of them were tentatively assigned. Amongst these, 12 isoflavone C-glycosides were identified. Hydroxyderivatives of puerarin in several isomeric forms were detected, some of which have not been previously reported in kudzu root. The molecular weights, interpretation of characteristic fragment ions obtained from HPLC-MS/MS and comparison with reported data allowed the putative identification of the isoflavone metabolites.
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Affiliation(s)
- Jeevan K Prasain
- Department of Pharmacology and Toxicology, University of Alabama at Birmingham, Birmingham, AL 35294, USA.
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11
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Deavours BE, Liu CJ, Naoumkina MA, Tang Y, Farag MA, Sumner LW, Noel JP, Dixon RA. Functional analysis of members of the isoflavone and isoflavanone O-methyltransferase enzyme families from the model legume Medicago truncatula. PLANT MOLECULAR BIOLOGY 2006; 62:715-33. [PMID: 17001495 PMCID: PMC2862459 DOI: 10.1007/s11103-006-9050-x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2006] [Accepted: 07/08/2006] [Indexed: 05/12/2023]
Abstract
Previous studies have identified two distinct O-methyltransferases (OMTs) implicated in isoflavonoid biosynthesis in Medicago species, a 7-OMT methylating the A-ring 7-hydroxyl of the isoflavone daidzein and a 4'-OMT methylating the B-ring 4'-hydroxyl of 2,7,4'-trihydroxyisoflavanone. Genes related to these OMTs from the model legume Medicago truncatula cluster as separate branches of the type I plant small molecule OMT family. To better understand the possible functions of these related OMTs in secondary metabolism in M. truncatula, seven of the OMTs were expressed in E. coli, purified, and their in vitro substrate preferences determined. Many of the enzymes display promiscuous activities, and some exhibit dual regio-specificity for the 4' and 7-hydroxyl moieties of the isoflavonoid nucleus. Protein structure homology modeling was used to help rationalize these catalytic activities. Transcripts encoding the different OMT genes exhibited differential tissue-specific and infection- or elicitor-induced expression, but not always in parallel with changes in expression of confirmed genes of the isoflavonoid pathway. The results are discussed in relation to the potential in vivo functions of these OMTs based on our current understanding of the phytochemistry of M. truncatula, and the difficulties associated with gene annotation in plant secondary metabolism.
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Affiliation(s)
- Bettina E. Deavours
- Plant Biology Division, Samuel Roberts Noble Foundation, 2510 Sam Noble Parkway, Ardmore, OK 73401, USA
- Department of Biology, Colorado State University, Fort Collins, CO 80523, USA
| | - Chang-Jun Liu
- Howard Hughes Medical Institute, Jack Skirball Chemical Biology and Proteomics Laboratory, The Salk Institute for Biological Studies, 10010 N. Torrey Pines Road, La Jolla, CA 92036, USA
- Biology Department, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - Marina A. Naoumkina
- Plant Biology Division, Samuel Roberts Noble Foundation, 2510 Sam Noble Parkway, Ardmore, OK 73401, USA
| | - Yuhong Tang
- Plant Biology Division, Samuel Roberts Noble Foundation, 2510 Sam Noble Parkway, Ardmore, OK 73401, USA
| | - Mohamed A. Farag
- Plant Biology Division, Samuel Roberts Noble Foundation, 2510 Sam Noble Parkway, Ardmore, OK 73401, USA
| | - Lloyd W. Sumner
- Plant Biology Division, Samuel Roberts Noble Foundation, 2510 Sam Noble Parkway, Ardmore, OK 73401, USA
| | - Joseph P. Noel
- Howard Hughes Medical Institute, Jack Skirball Chemical Biology and Proteomics Laboratory, The Salk Institute for Biological Studies, 10010 N. Torrey Pines Road, La Jolla, CA 92036, USA
| | - Richard A. Dixon
- Plant Biology Division, Samuel Roberts Noble Foundation, 2510 Sam Noble Parkway, Ardmore, OK 73401, USA
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Akashi T, Aoki T, Ayabe SI. Molecular and biochemical characterization of 2-hydroxyisoflavanone dehydratase. Involvement of carboxylesterase-like proteins in leguminous isoflavone biosynthesis. PLANT PHYSIOLOGY 2005; 137:882-91. [PMID: 15734910 PMCID: PMC1065389 DOI: 10.1104/pp.104.056747] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2004] [Revised: 12/17/2004] [Accepted: 12/20/2004] [Indexed: 05/17/2023]
Abstract
Isoflavonoids are ecophysiologically active secondary metabolites of the Leguminosae and known for health-promoting phytoestrogenic functions. Isoflavones are synthesized by 1,2-elimination of water from 2-hydroxyisoflavanones, the first intermediate with the isoflavonoid skeleton, but details of this dehydration have been unclear. We screened the extracts of repeatedly fractionated Escherichia coli expressing a Glycyrrhiza echinata cDNA library for the activity to convert a radiolabeled precursor into formononetin (7-hydroxy-4'-methoxyisoflavone), and a clone of 2-hydroxyisoflavanone dehydratase (HID) was isolated. Another HID cDNA was cloned from soybean (Glycine max), based on the sequence information in its expressed sequence tag library. Kinetic studies revealed that G. echinata HID is specific to 2,7-dihydroxy-4'-methoxyisoflavanone, while soybean HID has broader specificity to both 4'-hydroxylated and 4'-methoxylated 2-hydroxyisoflavanones, reflecting the structures of isoflavones contained in each plant species. Strikingly, HID proteins were members of a large carboxylesterase family, of which plant proteins form a monophyletic group and some are assigned defensive functions with no intrinsic catalytic activities identified. Site-directed mutagenesis with soybean HID protein suggested that the characteristic oxyanion hole and catalytic triad are essential for the dehydratase as well as the faint esterase activities. The findings, to our knowledge, represent a new example of recruitment of enzymes of primary metabolism during the molecular evolution of plant secondary metabolism.
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Affiliation(s)
- Tomoyoshi Akashi
- Department of Applied Biological Sciences, Nihon University, Fujisawa, Kanagawa 252-8510, Japan
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Akashi T, Sawada Y, Shimada N, Sakurai N, Aoki T, Ayabe SI. cDNA cloning and biochemical characterization of S-adenosyl-L-methionine: 2,7,4'-trihydroxyisoflavanone 4'-O-methyltransferase, a critical enzyme of the legume isoflavonoid phytoalexin pathway. PLANT & CELL PHYSIOLOGY 2003; 44:103-12. [PMID: 12610212 DOI: 10.1093/pcp/pcg034] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Formononetin (7-hydroxy-4'-methoxyisoflavone, also known as 4'-O-methyldaidzein) is an essential intermediate of ecophysiologically active leguminous isoflavonoids. The biosynthetic pathway to produce 4'-methoxyl of formononetin has been unknown because the methyl transfer from S-adenosyl-L-methionine (SAM) to 4'-hydroxyl of daidzein has never been detected in any plants. A hypothesis that SAM: daidzein 7-O-methyltransferase (D7OMT), an enzyme with a different regiospecificity, is involved in formononetin biosynthesis through its intracellular compartmentation with other enzymes recently prevails, but no direct evidence has been presented. We proposed a new scheme of formononetin biosynthesis involving 2,7,4'-trihydroxyisoflavanone as the methyl acceptor and subsequent dehydration. We now cloned a cDNA encoding SAM: 2,7,4'-trihydroxyisoflavanone 4'-O-methyltransferase (HI4'OMT) through the screening of functionally expressed Glycyrrhiza echinata (Fabaceae) cDNAs. The reaction product, 2,7-dihydroxy-4'-methoxyisoflavanone, was unambiguously identified. Recombinant G. echinata D7OMT did not show HI4'OMT activity, and G. echinata HI4'OMT protein free from D7OMT was partially purified. HI4'OMT is thus concluded to be distinct from D7OMT, and their distant phylogenetic relationship was further presented. HI4'OMT may be functionally identical to (+)-6a-hydroxymaackiain 3-OMT of pea. Homologous cDNAs were found in several legumes, and the catalytic function of the Lotus japonicus HI4'OMT was verified, indicating that HI4'OMT is the enzyme of formononetin biosynthesis in general legumes.
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Affiliation(s)
- Tomoyoshi Akashi
- Department of Applied Biological Sciences, Nihon University, Fujisawa, Kanagawa, 252-8510 Japan
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Ayabe SI, Akashi T, Aoki T. Cloning of cDNAs encoding P450s in flavonoid/isoflavonoid pathway from elicited leguminous cell cultures. Methods Enzymol 2003; 357:360-9. [PMID: 12424926 DOI: 10.1016/s0076-6879(02)57694-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Shin-ichi Ayabe
- Department of Applied Biological Sciences, Nihon University, Fujisawa, Kanagawa 252-8510, Japan
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