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David R. Gang - One of the best experts on this subject based on the ideXlab platform.
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identification and cloning of an nadph dependent hydroxycinnamoyl coa double bond reductase involved in dihydrochalcone formation in malus domestica borkh
Phytochemistry, 2014Co-Authors: Mwafaq Ibdah, Stefan Martens, Anna Berim, Andrea Lorena Herrera Valderrama, Luisa Palmieri, Efraim Lewinsohn, David R. GangAbstract:Abstract The apple tree ( Malus sp.) is an agriculturally and economically important source of food and beverages. Many of the health beneficial properties of apples are due to (poly)phenolic metabolites that they contain, including various dihydrochalcones. Although many of the genes and enzymes involved in polyphenol biosynthesis are known in many plant species, the specific reactions that lead to the biosynthesis of the dihydrochalcone precursor, p -dihydrocoumaroyl-CoA ( 3 ), are unknown. To identify genes involved in the synthesis of these metabolites, existing genome databases of the Rosaceae were screened for apple genes with significant sequence similarity to Arabidopsis alkenal double bond reductases. Herein described are the isolation and characterization of a Malus hydroxycinnamoyl-CoA double bond reductase, which catalyzed the NADPH-dependent reduction of p -coumaroyl-CoA and Feruloyl-CoA to p -dihydrocoumaroyl-CoA and dihydroFeruloyl-CoA, respectively. Its apparent K m values for p -coumaroyl-CoA, Feruloyl-CoA and NADPH were 96.6, 92.9 and 101.3 μM, respectively. The Malus double bond reductase preferred Feruloyl-CoA to p -coumaroyl-CoA as a substrate by a factor of 2.1 when comparing catalytic efficiencies in vitro . Expression analysis of the hydroxycinnamoyl-CoA double bond reductase gene revealed that its transcript levels showed significant variation in tissues of different developmental stages, but was expressed when expected for involvement in dihydrochalcone formation. Thus, the hydroxycinnamoyl-CoA double bond reductase appears to be responsible for the reduction of the α , β -unsaturated double bond of p -coumaroyl-CoA, the first step of dihydrochalcone biosynthesis in apple tissues, and may be involved in the production of these compounds.
Ian A. Dubery - One of the best experts on this subject based on the ideXlab platform.
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Similar, but different: structurally related azelaic acid and hexanoic acid trigger differential metabolomic and transcriptomic responses in tobacco cells
BMC Plant Biology, 2017Co-Authors: Arnaud T. Djami-tchatchou, Efficient N. Ncube, Paul A. Steenkamp, Ian A. DuberyAbstract:BackgroundPlants respond to various stress stimuli by activating an enhanced broad-spectrum defensive ability. The development of novel resistance inducers represents an attractive, alternative crop protection strategy. In this regard, hexanoic acid (Hxa, a chemical elicitor) and azelaic acid (Aza, a natural signaling compound) have been proposed as inducers of plant defense, by means of a priming mechanism. Here, we investigated both the mode of action and the complementarity of Aza and Hxa as priming agents in Nicotiana tabacum cells in support of enhanced defense.ResultsMetabolomic analyses identified signatory biomarkers involved in the establishment of a pre-conditioned state following Aza and Hxa treatment. Both inducers affected the metabolomes in a similar manner and generated common biomarkers: caffeoylputrescine glycoside, cis-5-caffeoylquinic acid, feruloylglycoside, feruloyl-3-methoxytyramine glycoside and feruloyl-3-methoxytyramine conjugate. Subsequently, quantitative real time-PCR was used to investigate the expression of inducible defense response genes: phenylalanine ammonia lyase, hydroxycinnamoyl CoA quinate transferase and hydroxycinnamoyl transferase to monitor activation of the early phenylpropanoid pathway and chlorogenic acids metabolism, while ethylene response element-binding protein, small sar1 GTPase, heat shock protein 90, RAR1, SGT1, non-expressor of PR genes 1 and thioredoxin were analyzed to report on signal transduction events. Pathogenesis-related protein 1a and defensin were quantified to investigate the activation of defenses regulated by salicylic acid and jasmonic acid respectively. The qPCR results revealed differential expression kinetics and, in general (except for NPR1, Thionin and PR1a), the relative gene expression ratios observed in the Hxa-treated cells were significantly greater than the expression observed in the cells treated with Aza.ConclusionsThe results indicate that Aza and Hxa have a similar priming effect through activation of genes involved in the establishment of systemic acquired resistance, associated with enhanced synthesis of hydroxycinnamic acids and related conjugates.
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similar but different structurally related azelaic acid and hexanoic acid trigger differential metabolomic and transcriptomic responses in tobacco cells
BMC Plant Biology, 2017Co-Authors: Arnaud T Djamitchatchou, Paul A. Steenkamp, Efficient N. Ncube, Ian A. DuberyAbstract:Plants respond to various stress stimuli by activating an enhanced broad-spectrum defensive ability. The development of novel resistance inducers represents an attractive, alternative crop protection strategy. In this regard, hexanoic acid (Hxa, a chemical elicitor) and azelaic acid (Aza, a natural signaling compound) have been proposed as inducers of plant defense, by means of a priming mechanism. Here, we investigated both the mode of action and the complementarity of Aza and Hxa as priming agents in Nicotiana tabacum cells in support of enhanced defense. Metabolomic analyses identified signatory biomarkers involved in the establishment of a pre-conditioned state following Aza and Hxa treatment. Both inducers affected the metabolomes in a similar manner and generated common biomarkers: caffeoylputrescine glycoside, cis-5-caffeoylquinic acid, feruloylglycoside, feruloyl-3-methoxytyramine glycoside and feruloyl-3-methoxytyramine conjugate. Subsequently, quantitative real time-PCR was used to investigate the expression of inducible defense response genes: phenylalanine ammonia lyase, hydroxycinnamoyl CoA quinate transferase and hydroxycinnamoyl transferase to monitor activation of the early phenylpropanoid pathway and chlorogenic acids metabolism, while ethylene response element-binding protein, small sar1 GTPase, heat shock protein 90, RAR1, SGT1, non-expressor of PR genes 1 and thioredoxin were analyzed to report on signal transduction events. Pathogenesis-related protein 1a and defensin were quantified to investigate the activation of defenses regulated by salicylic acid and jasmonic acid respectively. The qPCR results revealed differential expression kinetics and, in general (except for NPR1, Thionin and PR1a), the relative gene expression ratios observed in the Hxa-treated cells were significantly greater than the expression observed in the cells treated with Aza. The results indicate that Aza and Hxa have a similar priming effect through activation of genes involved in the establishment of systemic acquired resistance, associated with enhanced synthesis of hydroxycinnamic acids and related conjugates.
Sueharu Horinouchi - One of the best experts on this subject based on the ideXlab platform.
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identification and characterization of multiple curcumin synthases from the herb curcuma longa
FEBS Letters, 2009Co-Authors: Yohei Katsuyama, Tomoko Kita, Sueharu HorinouchiAbstract:Curcuminoids are pharmaceutically important compounds isolated from the herb Curcuma longa. Two additional type III polyketide synthases, named CURS2 and CURS3, that are capable of curcuminoid synthesis were identified and characterized. In vitro analysis revealed that CURS2 preferred Feruloyl-CoA as a starter substrate and CURS3 preferred both Feruloyl-CoA and p-coumaroyl-CoA. These results suggested that CURS2 synthesizes curcumin or demethoxycurcumin and CURS3 synthesizes curcumin, bisdemethoxycurcumin and demethoxycurcumin. The availability of the substrates and the expression levels of the three different enzymes capable of curcuminoid synthesis with different substrate specificities might influence the composition of curcuminoids in the turmeric and in different cultivars.
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curcuminoid biosynthesis by two type iii polyketide synthases in the herb curcuma longa
Journal of Biological Chemistry, 2009Co-Authors: Yohei Katsuyama, Tomoko Kita, Nobutaka Funa, Sueharu HorinouchiAbstract:Curcuminoids found in the rhizome of turmeric, Curcuma longa, possess various biological activities. Despite much attention regarding the biosynthesis of curcuminoids because of their pharmaceutically important properties and biosynthetically intriguing structures, no enzyme systems have been elucidated. Here we propose a pathway for curcuminoid biosynthesis in the herb C. longa, which includes two novel type III polyketide synthases. One of the type III polyketide synthases, named diketide-CoA synthase (DCS), catalyzed the formation of feruloyldiketide-CoA by condensing Feruloyl-CoA and malonyl-CoA. The other, named curcumin synthase (CURS), catalyzed the in vitro formation of curcuminoids from cinnamoyldiketide-N-acetylcysteamine (a mimic of the CoA ester) and Feruloyl-CoA. Co-incubation of DCS and CURS in the presence of Feruloyl-CoA and malonyl-CoA yielded curcumin at high efficiency, although CURS itself possessed low activity for the synthesis of curcumin from Feruloyl-CoA and malonyl-CoA. These findings thus revealed the curcumin biosynthetic route in turmeric, in which DCS synthesizes feruloyldiketide-CoA, and CURS then converts the diketide-CoA esters into a curcuminoid scaffold.
Mwafaq Ibdah - One of the best experts on this subject based on the ideXlab platform.
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identification and cloning of an nadph dependent hydroxycinnamoyl coa double bond reductase involved in dihydrochalcone formation in malus domestica borkh
Phytochemistry, 2014Co-Authors: Mwafaq Ibdah, Stefan Martens, Anna Berim, Andrea Lorena Herrera Valderrama, Luisa Palmieri, Efraim Lewinsohn, David R. GangAbstract:Abstract The apple tree ( Malus sp.) is an agriculturally and economically important source of food and beverages. Many of the health beneficial properties of apples are due to (poly)phenolic metabolites that they contain, including various dihydrochalcones. Although many of the genes and enzymes involved in polyphenol biosynthesis are known in many plant species, the specific reactions that lead to the biosynthesis of the dihydrochalcone precursor, p -dihydrocoumaroyl-CoA ( 3 ), are unknown. To identify genes involved in the synthesis of these metabolites, existing genome databases of the Rosaceae were screened for apple genes with significant sequence similarity to Arabidopsis alkenal double bond reductases. Herein described are the isolation and characterization of a Malus hydroxycinnamoyl-CoA double bond reductase, which catalyzed the NADPH-dependent reduction of p -coumaroyl-CoA and Feruloyl-CoA to p -dihydrocoumaroyl-CoA and dihydroFeruloyl-CoA, respectively. Its apparent K m values for p -coumaroyl-CoA, Feruloyl-CoA and NADPH were 96.6, 92.9 and 101.3 μM, respectively. The Malus double bond reductase preferred Feruloyl-CoA to p -coumaroyl-CoA as a substrate by a factor of 2.1 when comparing catalytic efficiencies in vitro . Expression analysis of the hydroxycinnamoyl-CoA double bond reductase gene revealed that its transcript levels showed significant variation in tissues of different developmental stages, but was expressed when expected for involvement in dihydrochalcone formation. Thus, the hydroxycinnamoyl-CoA double bond reductase appears to be responsible for the reduction of the α , β -unsaturated double bond of p -coumaroyl-CoA, the first step of dihydrochalcone biosynthesis in apple tissues, and may be involved in the production of these compounds.
Stefan Martens - One of the best experts on this subject based on the ideXlab platform.
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identification and cloning of an nadph dependent hydroxycinnamoyl coa double bond reductase involved in dihydrochalcone formation in malus domestica borkh
Phytochemistry, 2014Co-Authors: Mwafaq Ibdah, Stefan Martens, Anna Berim, Andrea Lorena Herrera Valderrama, Luisa Palmieri, Efraim Lewinsohn, David R. GangAbstract:Abstract The apple tree ( Malus sp.) is an agriculturally and economically important source of food and beverages. Many of the health beneficial properties of apples are due to (poly)phenolic metabolites that they contain, including various dihydrochalcones. Although many of the genes and enzymes involved in polyphenol biosynthesis are known in many plant species, the specific reactions that lead to the biosynthesis of the dihydrochalcone precursor, p -dihydrocoumaroyl-CoA ( 3 ), are unknown. To identify genes involved in the synthesis of these metabolites, existing genome databases of the Rosaceae were screened for apple genes with significant sequence similarity to Arabidopsis alkenal double bond reductases. Herein described are the isolation and characterization of a Malus hydroxycinnamoyl-CoA double bond reductase, which catalyzed the NADPH-dependent reduction of p -coumaroyl-CoA and Feruloyl-CoA to p -dihydrocoumaroyl-CoA and dihydroFeruloyl-CoA, respectively. Its apparent K m values for p -coumaroyl-CoA, Feruloyl-CoA and NADPH were 96.6, 92.9 and 101.3 μM, respectively. The Malus double bond reductase preferred Feruloyl-CoA to p -coumaroyl-CoA as a substrate by a factor of 2.1 when comparing catalytic efficiencies in vitro . Expression analysis of the hydroxycinnamoyl-CoA double bond reductase gene revealed that its transcript levels showed significant variation in tissues of different developmental stages, but was expressed when expected for involvement in dihydrochalcone formation. Thus, the hydroxycinnamoyl-CoA double bond reductase appears to be responsible for the reduction of the α , β -unsaturated double bond of p -coumaroyl-CoA, the first step of dihydrochalcone biosynthesis in apple tissues, and may be involved in the production of these compounds.