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The phenylpropanoid pathway of flavonoid biosynthesis has been the subject of considerable research attention. By contrast, the proposed polyketide pathway, also known as the acetate pathway, which provides malonyl-CoA moieties for the C2 elongation reaction catalyzed by chalcone synthase, is less well studied. Here, we identified four genes as candidates for involvement in the supply of cytosolic malonyl-CoA from the catabolism of acyl-CoA, based on coexpression analysis with other flavonoid-related genes. Two of these genes, ACC and KAT5, have been previously characterized with respect to their involvement in lipid metabolism, but no information concerning their relationship to flavonoid biosynthesis is available. To assess the occurrence and importance of the acetate pathway, we characterized the metabolomes of two mutant or transgenic Arabidopsis lines for each of the four enzymes of this putative pathway using a hierarchical approach covering primary and secondary metabolites as well as lipids. Intriguingly, not only flavonoid content but also glucosinolate content was altered in lines deficient in the acetate pathway, as were levels of lipids and most primary metabolites. We discuss these data in the context of our current understanding of flavonoids and lipid metabolism as well as with regard to improving human nutrition.

Cell suspension culture has been used as a model to study metabolic changes to several stresses. To have detailed information of nitrogen (N) limitation on sugarcane metabolism, a controlled study of the primary metabolites and representative compounds of secondary metabolism was developed using suspension cells growing under three different N regimes: normal condition (40 mmol·L–1 NO-3), slightly deficient (12 mmol·L–1 NO-3) and completely deficient (0 mmol·L–1 NO-3). Sugarcane cells were harvested after 3 and 7 days of treatment. A range of changes in the levels of amino acids, organic acids, sugars and phenolic compounds were observed upon the growth conditions applied. Nitrogen limitation remarkably affected the amino acids and carbohydrates biosynthesis, which, associated with the changes observed on phenolic compounds contents, indicates the upregulation of carbon sink compensation mechanisms in these sugarcane cells exposed to N starvation. As expected, the results showed that N limitation might cause an extensive metabolic reprogramming of both carbon and N metabolism in sugarcane cells, and these changes are related to the intensity of the starvation. Nitrogen is essential for plant growth and development, and its limitation sharply reduces crop yield. Thus, these results open new perspectives for in planta studies concerning carbon and N metabolisms balance in this crop.

During the maturation phase of flower development, the onset of anthesis visibly marks the transition from buds to open flowers, during which petals stretch out, nectar secretion commences, and pollination occurs. Analysis of the metabolic changes occurring during this developmental transition has primarily focused on specific classes of metabolites, such as pigments and scent emission, and far less on the whole network of primary and secondary metabolites. To investigate the metabolic changes occurring at anthesis, we performed multi-platform metabolomics alongside RNA sequencing in individual florets harvested from the main inflorescence of Arabidopsis (Arabidopsis thaliana) ecotype Col-0. To trace metabolic fluxes at the level of the whole inflorescence and individual florets, we further integrated these studies with radiolabeled experiments. These extensive analyses revealed high-energy-level metabolism and transport of carbohydrates and amino acids, supporting intense metabolic rearrangements occurring at the time of this floral transition. These comprehensive data are discussed in the context of our current understanding of the metabolic shifts underlying flower opening. We envision that this analysis will facilitate the introgression of floral metabolic traits promoting pollination in crop species for which a comprehensive knowledge of flower metabolism is still limited.

Common bean (Phaseolus vulgaris L.) is an important legume species with a rich natural diversity of lan-draces that originated from the wild forms following multiple independent domestication events. After the publication of its genome, several resources for this relevant crop have been made available. A comprehen-sive characterization of specialized metabolism in P. vulgaris, however, is still lacking. In this study, we used a metabolomics approach based on liquid chromatography-mass spectrometry to dissect the chemical composition at a tissue-specific level in several accessions of common bean belonging to different gene pools. Using a combination of literature search, mass spectral interpretation, 13C-labeling, and correlation analyses, we were able to assign chemical classes and/or putative structures for approximately 39% of all measured metabolites. Additionally, we integrated this information with transcriptomics data and phyloge-netic inference from multiple legume species to reconstruct the possible metabolic pathways and identify sets of candidate genes involved in the biosynthesis of specialized metabolites. A particular focus was given to flavonoids, triterpenoid saponins and hydroxycinnamates, as they represent metabolites involved in important ecological interactions and they are also associated with several health-promoting benefits when integrated into the human diet. The data are presented here in the form of an accessible resource that we hope will set grounds for further studies on specialized metabolism in legumes.

During the maturation phase of flower development, the onset of anthesis visibly marks the transition from buds to open flowers, during which petals stretch out, nectar secretion commences, and pollination occurs. Analysis of the metabolic changes occurring during this developmental transition has primarily focused on specific classes of metabolites, such as pigments and scent emission, and far less on the whole network of primary and secondary metabolites. To investigate the metabolic changes occurring at anthesis, we performed multi-platform metabolomics alongside RNA sequencing in individual florets harvested from the main inflorescence of Arabidopsis (Arabidopsis thaliana) ecotype Col-0. To trace metabolic fluxes at the level of the whole inflorescence and individual florets, we further integrated these studies with radiolabeled experiments. These extensive analyses revealed high-energy-level metabolism and transport of carbohydrates and amino acids, supporting intense metabolic rearrangements occurring at the time of this floral transition. These comprehensive data are discussed in the context of our current understanding of the metabolic shifts underlying flower opening. We envision that this analysis will facilitate the introgression of floral metabolic traits promoting pollination in crop species for which a comprehensive knowledge of flower metabolism is still limited., identifier:1532-2548

Cell suspension culture has been used as a model to study metabolic changes to several stresses. To have detailed information of nitrogen (N) limitation on sugarcane metabolism, a controlled study of the primary metabolites and representative compounds of secondary metabolism was developed using suspension cells growing under three different N regimes: normal condition (40 mmol·L–1 NO-3), slightly deficient (12 mmol·L–1 NO-3) and completely deficient (0 mmol·L–1 NO-3). Sugarcane cells were harvested after 3 and 7 days of treatment. A range of changes in the levels of amino acids, organic acids, sugars and phenolic compounds were observed upon the growth conditions applied. Nitrogen limitation remarkably affected the amino acids and carbohydrates biosynthesis, which, associated with the changes observed on phenolic compounds contents, indicates the upregulation of carbon sink compensation mechanisms in these sugarcane cells exposed to N starvation. As expected, the results showed that N limitation might cause an extensive metabolic reprogramming of both carbon and N metabolism in sugarcane cells, and these changes are related to the intensity of the starvation. Nitrogen is essential for plant growth and development, and its limitation sharply reduces crop yield. Thus, these results open new perspectives for in planta studies concerning carbon and N metabolisms balance in this crop., identifier:1678-4499

The phenylpropanoid pathway of flavonoid biosynthesis has been the subject of considerable research attention. By contrast, the proposed polyketide pathway, also known as the acetate pathway, which provides malonyl-CoA moieties for the C2 elongation reaction catalyzed by chalcone synthase, is less well studied. Here, we identified four genes as candidates for involvement in the supply of cytosolic malonyl-CoA from the catabolism of acyl-CoA, based on coexpression analysis with other flavonoid-related genes. Two of these genes, ACC and KAT5, have been previously characterized with respect to their involvement in lipid metabolism, but no information concerning their relationship to flavonoid biosynthesis is available. To assess the occurrence and importance of the acetate pathway, we characterized the metabolomes of two mutant or transgenic Arabidopsis lines for each of the four enzymes of this putative pathway using a hierarchical approach covering primary and secondary metabolites as well as lipids. Intriguingly, not only flavonoid content but also glucosinolate content was altered in lines deficient in the acetate pathway, as were levels of lipids and most primary metabolites. We discuss these data in the context of our current understanding of flavonoids and lipid metabolism as well as with regard to improving human nutrition., identifier:1532-2548

The phenylpropanoid pathway of flavonoid biosynthesis has been the subject of considerable research attention. By contrast, the proposed polyketide pathway, also known as the acetate pathway, which provides malonyl-CoA moieties for the C2 elongation reaction catalyzed by chalcone synthase, is less well studied. Here, we identified four genes as candidates for involvement in the supply of cytosolic malonyl-CoA from the catabolism of acyl-CoA, based on coexpression analysis with other flavonoid-related genes. Two of these genes, ACC and KAT5, have been previously characterized with respect to their involvement in lipid metabolism, but no information concerning their relationship to flavonoid biosynthesis is available. To assess the occurrence and importance of the acetate pathway, we characterized the metabolomes of two mutant or transgenic Arabidopsis lines for each of the four enzymes of this putative pathway using a hierarchical approach covering primary and secondary metabolites as well as lipids. Intriguingly, not only flavonoid content but also glucosinolate content was altered in lines deficient in the acetate pathway, as were levels of lipids and most primary metabolites. We discuss these data in the context of our current understanding of flavonoids and lipid metabolism as well as with regard to improving human nutrition.

Common bean (Phaseolus vulgaris L.) is an important legume species with a rich natural diversity of lan-draces that originated from the wild forms following multiple independent domestication events. After the publication of its genome, several resources for this relevant crop have been made available. A comprehen-sive characterization of specialized metabolism in P. vulgaris, however, is still lacking. In this study, we used a metabolomics approach based on liquid chromatography-mass spectrometry to dissect the chemical composition at a tissue-specific level in several accessions of common bean belonging to different gene pools. Using a combination of literature search, mass spectral interpretation, 13C-labeling, and correlation analyses, we were able to assign chemical classes and/or putative structures for approximately 39% of all measured metabolites. Additionally, we integrated this information with transcriptomics data and phyloge-netic inference from multiple legume species to reconstruct the possible metabolic pathways and identify sets of candidate genes involved in the biosynthesis of specialized metabolites. A particular focus was given to flavonoids, triterpenoid saponins and hydroxycinnamates, as they represent metabolites involved in important ecological interactions and they are also associated with several health-promoting benefits when integrated into the human diet. The data are presented here in the form of an accessible resource that we hope will set grounds for further studies on specialized metabolism in legumes., identifier:1365-313X

Common bean (Phaseolus vulgaris L.) is an important legume species with a rich natural diversity of lan-draces that originated from the wild forms following multiple independent domestication events. After the publication of its genome, several resources for this relevant crop have been made available. A comprehen-sive characterization of specialized metabolism in P. vulgaris, however, is still lacking. In this study, we used a metabolomics approach based on liquid chromatography-mass spectrometry to dissect the chemical composition at a tissue-specific level in several accessions of common bean belonging to different gene pools. Using a combination of literature search, mass spectral interpretation, 13C-labeling, and correlation analyses, we were able to assign chemical classes and/or putative structures for approximately 39% of all measured metabolites. Additionally, we integrated this information with transcriptomics data and phyloge-netic inference from multiple legume species to reconstruct the possible metabolic pathways and identify sets of candidate genes involved in the biosynthesis of specialized metabolites. A particular focus was given to flavonoids, triterpenoid saponins and hydroxycinnamates, as they represent metabolites involved in important ecological interactions and they are also associated with several health-promoting benefits when integrated into the human diet. The data are presented here in the form of an accessible resource that we hope will set grounds for further studies on specialized metabolism in legumes.

Bruna Vidal Bonifácio,1 Matheus Aparecido dos Santos Ramos,1 Patrícia Bento da Silva,2 Kamila Maria Silveira Negri,1 Érica de Oliveira Lopes,1 Leonardo Perez de Souza,3 Wagner Vilegas,4 Fernando Rogério Pavan,1 Marlus Chorilli,2 Taís Maria Bauab11Department of Biological Sciences, 2Department of Drugs and Medicines, School of Pharmaceutical Sciences, 3Department of Organic Chemistry, Chemistry Institute, UNESP – Univ Estadual Paulista, Araraquara, São Paulo, Brazil; 4Coastal Campus of São Vicente, UNESP – Univ Estadual Paulista, São Vicente, São Paulo, BrazilAbstract: The genus Astronium (Anacardiaceae) includes species, such as Astronium fraxinifolium, Astronium graveolens, and Astronium urundeuva, which possess anti-inflammatory, anti-ulcerogenic, healing, and antimicrobial properties. Nanostructured lipid systems are able to potentiate the action of plant extracts, reducing the required dose and side effects and improving antimicrobial activity. This work aims to evaluate a nanostructured lipid system that was developed as a strategy to improve the anti-Candida albicans activity of hydroethanolic extracts of stems and leaves from Astronium sp. The antifungal activity against C. albicans (ATCC 18804) was evaluated in vitro by a microdilution technique. In addition to the in vitro assays, the Astronium sp. that showed the best antifungal activity and selectivity index was submitted to an in vivo assay using a model of vulvovaginal candidiasis infection. In these assays, the extracts were either used alone or were incorporated into the nanostructured lipid system (comprising 10% oil phase, 10% surfactant, and 80% aqueous phase). The results indicated a minimal inhibitory concentration of 125.00 µg/mL before incorporation into the nanostructured system; this activity was even more enhanced when this extract presented a minimal inhibitory co