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Reuben J Peters - One of the best experts on this subject based on the ideXlab platform.
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probing labdane related Diterpenoid biosynthesis in the fungal genus aspergillus
Journal of Natural Products, 2017Co-Authors: Meimei Xu, Matthew L Hillwig, Mollie S Tiernan, Reuben J PetersAbstract:While terpenoid production is generally associated with plants, a variety of fungi contain operons predicted to lead to such biosynthesis. Notably, fungi contain a number of cyclases characteristic of labdane-related Diterpenoid metabolism, which have not been much explored. These also are often found near cytochrome P450 (CYP) mono-oxygenases that presumably further decorate the ensuing diterpene, suggesting that these fungi might produce more elaborate Diterpenoids. To probe the functional diversity of such biosynthetic capacity, an investigation of the phylogenetically diverse cyclases and associated CYPs from the fungal genus Aspergillus was undertaken, revealing their ability to produce isopimaradiene-derived Diterpenoids. Intriguingly, labdane-related Diterpenoid biosynthetic genes are largely found in plant-associated fungi, hinting that these natural products may play a role in such interactions. Accordingly, it is hypothesized here that isopimarane production may assist the plant-saprophytic life...
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Investigation of the chemical interface in the soybean-aphid and rice-bacteria interactions using maldi-mass spectrometry imaging
Analytical Chemistry, 2015Co-Authors: Adam T Klein, Gargey B. Yagnik, Jessica D. Hohenstein, Malinda D. Reichert, Zhiyuan Ji, Gustavo C Macintosh, Jiachen Zi, Reuben J Peters, Bing Yang, Javier VelaAbstract:Mass spectrometry imaging (MSI) is an emerging technology for high-resolution plant biology. It has been utilized to study plant-pest interactions, but limited to the surface interfaces. Here we expand the technology to explore the chemical interactions occurring inside the plant tissues. Two sample preparation methods, imprinting and fracturing, were developed and applied, for the first time, to visualize internal metabolites of leaves in matrix-assisted laser desorption ionization (MALDI)-MSI. This is also the first time nanoparticle-based ionization was implemented to ionize Diterpenoid phytochemicals that were difficult to analyze with traditional organic matrices. The interactions between rice-bacterium and soybean-aphid were investigated as two model systems to demonstrate the capability of high-resolution MSI based on MALDI. Localized molecular information on various plant- or pest-derived chemicals provided valuable insight for the molecular processes occurring during the plant-pest interactions. Specifically, salicylic acid and isoflavone based resistance was visualized in the soybean-aphid system and antibiotic Diterpenoids in rice-bacterium interactions.
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functional characterization of wheat ent kaurene like synthases indicates continuing evolution of labdane related Diterpenoid metabolism in the cereals
Phytochemistry, 2012Co-Authors: Ke Zhou, Meimei Xu, Mollie S Tiernan, Tomonobu Toyomasu, Chizu Sugawara, Masami Usui, Wataru Mitsuhashi, Makiko Chono, Peter M Chandler, Reuben J PetersAbstract:Abstract Wheat (Triticum aestivum) and rice (Oryza sativa) are two of the most agriculturally important cereal crop plants. Rice is known to produce numerous Diterpenoid natural products that serve as phytoalexins and/or allelochemicals. Specifically, these are labdane-related Diterpenoids, derived from a characteristic labdadienyl/copalyl diphosphate (CPP), whose biosynthetic relationship to gibberellin biosynthesis is evident from the relevant expanded and functionally diverse family of ent-kaurene synthase-like (KSL) genes found in rice the (OsKSLs). Herein reported is the biochemical characterization of a similarly expansive family of KSL from wheat (the TaKSLs). In particular, beyond ent-kaurene synthases (KS), wheat also contains several biochemically diversified KSLs. These react either with the ent-CPP intermediate common to gibberellin biosynthesis or with the normal stereoisomer of CPP that also is found in wheat (as demonstrated by the accompanying paper describing the wheat CPP synthases). Comparison with a barley (Hordeum vulgare) KS indicates conservation of monocot KS, with early and continued expansion and functional diversification of KSLs in at least the small grain cereals. In addition, some of the TaKSLs that utilize normal CPP also will react with syn-CPP, echoing previous findings with the OsKSL family, with such enzymatic promiscuity/elasticity providing insight into the continuing evolution of Diterpenoid metabolism in the cereal crop plant family, as well as more generally, which is discussed here.
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functional characterization of wheat copalyl diphosphate synthases sheds light on the early evolution of labdane related Diterpenoid metabolism in the cereals
Phytochemistry, 2012Co-Authors: Yisheng Wu, Ke Zhou, Tomonobu Toyomasu, Chizu Sugawara, Masami Usui, Wataru Mitsuhashi, Makiko Chono, Peter M Chandler, Reuben J PetersAbstract:Abstract Two of the most agriculturally important cereal crop plants are wheat (Triticum aestivum) and rice (Oryza sativa). Rice has been shown to produce a number of Diterpenoid natural products as phytoalexins and/or allelochemicals – specifically, labdane-related Diterpenoids, whose biosynthesis proceeds via formation of an eponymous labdadienyl/copalyl diphosphate (CPP) intermediate (e.g., the ent-CPP of gibberellin phytohormone biosynthesis). Similar to rice, wheat encodes a number of CPP synthases (CPS), and the three CPS characterized to date (TaCPS1–3) all have been suggested to produce ent-CPP. However, several of the downstream diterpene synthases will only react with CPP intermediate of normal or syn, but not ent, stereochemistry, as described in the accompanying report. Investigation of additional CPS did not resolve this issue, as the only other functional synthase (TaCPS4) also produced ent-CPP. Chiral product characterization of all the TaCPS then established that TaCPS2 uniquely produces normal, rather than ent-, CPP, thus, providing a suitable substrate source for the downstream diterpene synthases. Notably, TaCPS2 is most homologous to the similarly stereochemically differentiated syn-CPP synthase from rice (OsCPS4), while the non-inducible TaCPS3 and TaCPS4 cluster with the rice OsCPS1 required for gibberellin phytohormone biosynthesis, as well as with a barley (Hordeum vulgare) CPS (HvCPS1) that also is characterized here as similarly producing ent-CPP. These results suggest that diversification of labdane-related Diterpenoid metabolism beyond the ancestral gibberellins occurred early in cereal evolution, and included the type of stereochemical variation demonstrated here.
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two rings in them all the labdane related Diterpenoids
Natural Product Reports, 2010Co-Authors: Reuben J PetersAbstract:Covering: up to the end of March 2010 Unlike the majority of terpenoids, a significant fraction of the polycyclic Diterpenoids (∼7000 already known) are now understood to originate from dual, rather than single, biosynthetic cyclization and/or rearrangement reactions, which proceed via a bicyclic diphosphate intermediate. The trivial name for the hydrocarbon skeleton of the most commonly found version of this biosynthetic intermediate forms the basis for a unifying “labdane-related” designation for this large super-family of natural products. Notably, many of these are found in plants, where the requisite biosynthetic machinery for gibberellin phytohormones, particularly the relevant diterpene cyclases, provides a biosynthetic reservoir that appears to have been repeatedly drawn upon to evolve new labdane-related Diterpenoids. The potent biological activity of the “ancestral” gibberellins, which has led to the independent evolution of distinct gibberellin biosynthetic pathways in plants, fungi, and bacteria, is further discussed as an archetypical example of the selective pressure driving evolution of the large super-family of labdane-related Diterpenoid natural products, with the observed diversification suggesting that their underlying hydrocarbon skeletal structures might serve as privileged scaffolds from which biological activity is readily derived.
Meimei Xu - One of the best experts on this subject based on the ideXlab platform.
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probing labdane related Diterpenoid biosynthesis in the fungal genus aspergillus
Journal of Natural Products, 2017Co-Authors: Meimei Xu, Matthew L Hillwig, Mollie S Tiernan, Reuben J PetersAbstract:While terpenoid production is generally associated with plants, a variety of fungi contain operons predicted to lead to such biosynthesis. Notably, fungi contain a number of cyclases characteristic of labdane-related Diterpenoid metabolism, which have not been much explored. These also are often found near cytochrome P450 (CYP) mono-oxygenases that presumably further decorate the ensuing diterpene, suggesting that these fungi might produce more elaborate Diterpenoids. To probe the functional diversity of such biosynthetic capacity, an investigation of the phylogenetically diverse cyclases and associated CYPs from the fungal genus Aspergillus was undertaken, revealing their ability to produce isopimaradiene-derived Diterpenoids. Intriguingly, labdane-related Diterpenoid biosynthetic genes are largely found in plant-associated fungi, hinting that these natural products may play a role in such interactions. Accordingly, it is hypothesized here that isopimarane production may assist the plant-saprophytic life...
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functional characterization of wheat ent kaurene like synthases indicates continuing evolution of labdane related Diterpenoid metabolism in the cereals
Phytochemistry, 2012Co-Authors: Ke Zhou, Meimei Xu, Mollie S Tiernan, Tomonobu Toyomasu, Chizu Sugawara, Masami Usui, Wataru Mitsuhashi, Makiko Chono, Peter M Chandler, Reuben J PetersAbstract:Abstract Wheat (Triticum aestivum) and rice (Oryza sativa) are two of the most agriculturally important cereal crop plants. Rice is known to produce numerous Diterpenoid natural products that serve as phytoalexins and/or allelochemicals. Specifically, these are labdane-related Diterpenoids, derived from a characteristic labdadienyl/copalyl diphosphate (CPP), whose biosynthetic relationship to gibberellin biosynthesis is evident from the relevant expanded and functionally diverse family of ent-kaurene synthase-like (KSL) genes found in rice the (OsKSLs). Herein reported is the biochemical characterization of a similarly expansive family of KSL from wheat (the TaKSLs). In particular, beyond ent-kaurene synthases (KS), wheat also contains several biochemically diversified KSLs. These react either with the ent-CPP intermediate common to gibberellin biosynthesis or with the normal stereoisomer of CPP that also is found in wheat (as demonstrated by the accompanying paper describing the wheat CPP synthases). Comparison with a barley (Hordeum vulgare) KS indicates conservation of monocot KS, with early and continued expansion and functional diversification of KSLs in at least the small grain cereals. In addition, some of the TaKSLs that utilize normal CPP also will react with syn-CPP, echoing previous findings with the OsKSL family, with such enzymatic promiscuity/elasticity providing insight into the continuing evolution of Diterpenoid metabolism in the cereal crop plant family, as well as more generally, which is discussed here.
Shaojiang Song - One of the best experts on this subject based on the ideXlab platform.
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kaurane and abietane Diterpenoids from the roots of tripterygium wilfordii and their cytotoxic evaluation
Bioorganic & Medicinal Chemistry Letters, 2016Co-Authors: Di Wang, Xiaoxiao Huang, Yan Zhang, Shaojiang SongAbstract:Abstract Kaurane Diterpenoids and abietane Diterpenoids are the major anti-tumor components in Tripterygium wilfordii (Celastraceae). Extraction of Tripterygium wilfordii afforded a new Diterpenoid and twenty known Diterpenoids belonging to the abietane and ent-kaurane families. The structures of all these compounds were characterized by spectroscopic techniques. All compounds were evaluated using the MTT method for in vitro cytotoxicity against six human cancer cell lines (HepG2, Hep3B, Bcap37, U251, MCF-7 and A549). Compounds 7 and 12 exhibited marked cytotoxicity against a six cell lines with IC 50 values in the range 5.10–23.30 μM. The structure–cytotoxic activity relationships of these Diterpenoids are also discussed.
Ke Zhou - One of the best experts on this subject based on the ideXlab platform.
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functional characterization of wheat ent kaurene like synthases indicates continuing evolution of labdane related Diterpenoid metabolism in the cereals
Phytochemistry, 2012Co-Authors: Ke Zhou, Meimei Xu, Mollie S Tiernan, Tomonobu Toyomasu, Chizu Sugawara, Masami Usui, Wataru Mitsuhashi, Makiko Chono, Peter M Chandler, Reuben J PetersAbstract:Abstract Wheat (Triticum aestivum) and rice (Oryza sativa) are two of the most agriculturally important cereal crop plants. Rice is known to produce numerous Diterpenoid natural products that serve as phytoalexins and/or allelochemicals. Specifically, these are labdane-related Diterpenoids, derived from a characteristic labdadienyl/copalyl diphosphate (CPP), whose biosynthetic relationship to gibberellin biosynthesis is evident from the relevant expanded and functionally diverse family of ent-kaurene synthase-like (KSL) genes found in rice the (OsKSLs). Herein reported is the biochemical characterization of a similarly expansive family of KSL from wheat (the TaKSLs). In particular, beyond ent-kaurene synthases (KS), wheat also contains several biochemically diversified KSLs. These react either with the ent-CPP intermediate common to gibberellin biosynthesis or with the normal stereoisomer of CPP that also is found in wheat (as demonstrated by the accompanying paper describing the wheat CPP synthases). Comparison with a barley (Hordeum vulgare) KS indicates conservation of monocot KS, with early and continued expansion and functional diversification of KSLs in at least the small grain cereals. In addition, some of the TaKSLs that utilize normal CPP also will react with syn-CPP, echoing previous findings with the OsKSL family, with such enzymatic promiscuity/elasticity providing insight into the continuing evolution of Diterpenoid metabolism in the cereal crop plant family, as well as more generally, which is discussed here.
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functional characterization of wheat copalyl diphosphate synthases sheds light on the early evolution of labdane related Diterpenoid metabolism in the cereals
Phytochemistry, 2012Co-Authors: Yisheng Wu, Ke Zhou, Tomonobu Toyomasu, Chizu Sugawara, Masami Usui, Wataru Mitsuhashi, Makiko Chono, Peter M Chandler, Reuben J PetersAbstract:Abstract Two of the most agriculturally important cereal crop plants are wheat (Triticum aestivum) and rice (Oryza sativa). Rice has been shown to produce a number of Diterpenoid natural products as phytoalexins and/or allelochemicals – specifically, labdane-related Diterpenoids, whose biosynthesis proceeds via formation of an eponymous labdadienyl/copalyl diphosphate (CPP) intermediate (e.g., the ent-CPP of gibberellin phytohormone biosynthesis). Similar to rice, wheat encodes a number of CPP synthases (CPS), and the three CPS characterized to date (TaCPS1–3) all have been suggested to produce ent-CPP. However, several of the downstream diterpene synthases will only react with CPP intermediate of normal or syn, but not ent, stereochemistry, as described in the accompanying report. Investigation of additional CPS did not resolve this issue, as the only other functional synthase (TaCPS4) also produced ent-CPP. Chiral product characterization of all the TaCPS then established that TaCPS2 uniquely produces normal, rather than ent-, CPP, thus, providing a suitable substrate source for the downstream diterpene synthases. Notably, TaCPS2 is most homologous to the similarly stereochemically differentiated syn-CPP synthase from rice (OsCPS4), while the non-inducible TaCPS3 and TaCPS4 cluster with the rice OsCPS1 required for gibberellin phytohormone biosynthesis, as well as with a barley (Hordeum vulgare) CPS (HvCPS1) that also is characterized here as similarly producing ent-CPP. These results suggest that diversification of labdane-related Diterpenoid metabolism beyond the ancestral gibberellins occurred early in cereal evolution, and included the type of stereochemical variation demonstrated here.
Mollie S Tiernan - One of the best experts on this subject based on the ideXlab platform.
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probing labdane related Diterpenoid biosynthesis in the fungal genus aspergillus
Journal of Natural Products, 2017Co-Authors: Meimei Xu, Matthew L Hillwig, Mollie S Tiernan, Reuben J PetersAbstract:While terpenoid production is generally associated with plants, a variety of fungi contain operons predicted to lead to such biosynthesis. Notably, fungi contain a number of cyclases characteristic of labdane-related Diterpenoid metabolism, which have not been much explored. These also are often found near cytochrome P450 (CYP) mono-oxygenases that presumably further decorate the ensuing diterpene, suggesting that these fungi might produce more elaborate Diterpenoids. To probe the functional diversity of such biosynthetic capacity, an investigation of the phylogenetically diverse cyclases and associated CYPs from the fungal genus Aspergillus was undertaken, revealing their ability to produce isopimaradiene-derived Diterpenoids. Intriguingly, labdane-related Diterpenoid biosynthetic genes are largely found in plant-associated fungi, hinting that these natural products may play a role in such interactions. Accordingly, it is hypothesized here that isopimarane production may assist the plant-saprophytic life...
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functional characterization of wheat ent kaurene like synthases indicates continuing evolution of labdane related Diterpenoid metabolism in the cereals
Phytochemistry, 2012Co-Authors: Ke Zhou, Meimei Xu, Mollie S Tiernan, Tomonobu Toyomasu, Chizu Sugawara, Masami Usui, Wataru Mitsuhashi, Makiko Chono, Peter M Chandler, Reuben J PetersAbstract:Abstract Wheat (Triticum aestivum) and rice (Oryza sativa) are two of the most agriculturally important cereal crop plants. Rice is known to produce numerous Diterpenoid natural products that serve as phytoalexins and/or allelochemicals. Specifically, these are labdane-related Diterpenoids, derived from a characteristic labdadienyl/copalyl diphosphate (CPP), whose biosynthetic relationship to gibberellin biosynthesis is evident from the relevant expanded and functionally diverse family of ent-kaurene synthase-like (KSL) genes found in rice the (OsKSLs). Herein reported is the biochemical characterization of a similarly expansive family of KSL from wheat (the TaKSLs). In particular, beyond ent-kaurene synthases (KS), wheat also contains several biochemically diversified KSLs. These react either with the ent-CPP intermediate common to gibberellin biosynthesis or with the normal stereoisomer of CPP that also is found in wheat (as demonstrated by the accompanying paper describing the wheat CPP synthases). Comparison with a barley (Hordeum vulgare) KS indicates conservation of monocot KS, with early and continued expansion and functional diversification of KSLs in at least the small grain cereals. In addition, some of the TaKSLs that utilize normal CPP also will react with syn-CPP, echoing previous findings with the OsKSL family, with such enzymatic promiscuity/elasticity providing insight into the continuing evolution of Diterpenoid metabolism in the cereal crop plant family, as well as more generally, which is discussed here.