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1.
Environ Monit Assess ; 192(11): 673, 2020 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-33011855

RESUMO

Plant responses to heavy metals and their storage constitute a crucial step to understand the environmental impacts of metallic trace elements (MTEs). In controlled experiments, we previously demonstrated the tolerance and resilience of Japanese knotweed to soil artificial polymetallic contamination. Using the same experimental design, we tested here the effect of three individual MTEs on Fallopia × bohemica performance traits. Rhizome fragments from three different sites (considered as distinct morphotypes) were grown in a greenhouse for 1 month on a prairial soil artificially contaminated with either Cd, Cr (VI) or Zn at concentrations corresponding to relatively highly polluted soils. Our results confirmed the high tolerance of Bohemian knotweed to metal stress, though, plant response to MTE pollution was dependant on MTE identity. Bohemian knotweed was stimulated by Cr (VI) (increased root and aerial masses), did not display any measurable change in performance traits under Cd at the high dose of 10 mg kg-1, and uptook all MTEs in its rhizome, but only Zn was transferred to its aerial parts. We also highlighted changes in root secondary metabolism that were more accentuated with Zn, including the increase of anthraquinone, stilbene and biphenyl derivatives. These results compared to multi-contamination experiments previously published suggest complex interactions between metals and plant, depending principally on metal identity and also suggest a potential role of soil microbes in the interactions.


Assuntos
Fallopia , Poluentes do Solo/análise , Poluentes do Solo/toxicidade , Cádmio , Monitoramento Ambiental , Metabolismo Secundário , Zinco
2.
Int J Nanomedicine ; 15: 5345-5360, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32801693

RESUMO

Background: Soft corals have been endorsed as a plentiful source of bioactive compounds with promising anti-inflammatory activities; therefore, exploring their potential as source of anti-inflammatory metabolites has stimulated a growing research interest. Purpose: To investigate the anti-inflammatory potential of the soft coral, Nephthea sp., in its bulk and silver nanostructure. Metabolomics analysis of Nephthea sp., followed by molecular docking studies, was also conducted in order to explore and predict the secondary metabolites that might provide its inhibitory actions on inflammation. Materials and Methods: The petroleum ether and ethyl acetate fractions were used to synthesize silver nanoparticles. The prepared silver nanoparticles were characterized through UV-vis spectrophotometric, transmission electron microscopy (TEM) and Fourier-transform infrared spectroscopy (FTIR) analyses. Testing for the anti-inflammatory activity was performed against COX-1 and COX-2. Furthermore, liquid chromatography-mass spectrometry (LC-MS) based metabolomics analysis and molecular docking were also applied. Results: A variety of secondary metabolites were identified, among them, sesquiterpenes were found to prevail. The petroleum ether and acetone fractions of Nephthea sp. showed the highest COX-2 inhibitory activities, possibly attributable to their substantial contents of terpenoids. Additionally, the green synthesized silver nanoparticles of both the petroleum ether and ethyl acetate fractions of Nephthea sp. demonstrated higher anti-COX-2 properties. Conclusion: The obtained results showed the effectiveness of non-targeted metabolomics technique in metabolic profiling of Nephthea sp., helping the search for new bioactive metabolites in future chemical studies on this soft coral. The interesting anti-inflammatory potential of the tested extracts and their nanoparticles could also be relevant to the development of new, effective anti-inflammatory agents.


Assuntos
Antozoários/metabolismo , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Nanopartículas Metálicas/química , Prata/química , Alcanos/química , Animais , Antozoários/química , Anti-Inflamatórios/síntese química , Ciclo-Oxigenase 1/química , Ciclo-Oxigenase 1/metabolismo , Inibidores de Ciclo-Oxigenase 2/química , Inibidores de Ciclo-Oxigenase 2/farmacologia , Inibidores de Ciclo-Oxigenase/química , Inibidores de Ciclo-Oxigenase/farmacologia , Química Verde , Humanos , Metabolômica , Simulação de Acoplamento Molecular , Metabolismo Secundário , Sesquiterpenos/análise , Espectrometria de Massas por Ionização por Electrospray , Espectroscopia de Infravermelho com Transformada de Fourier
3.
Ying Yong Sheng Tai Xue Bao ; 31(7): 2161-2167, 2020 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-32715677

RESUMO

Plants can produce diverse groups of secondary metabolites to adapt to environment. Many secondary metabolites are involved in the defense responses against pathogenic microbes, including phytoanticipins which are low molecular weight anti-microbial compounds presented in plants before infection, and phytoalexins produced by plants de novo in response to pathogen attack. Phytoalexins are an important part of plant defense repertoire to pathogenic microbes, especially to necrotrophs. Since the concept of phytoalexin was proposed 80 years ago, many kinds of phytoalexins were identified. In contrast, the biosynthesis of most phytoalexins and their regulatory networks are largely unknown. In this review, I summarized recent research progress of phytoalexins in Arabidopsis and Nicotiana species, with special focus on molecular regulations of their biosynthesis. The problems and future directions in phytoalexin research were also discussed.


Assuntos
Arabidopsis , Sesquiterpenos , Metabolismo Secundário , Tabaco
4.
PLoS One ; 15(6): e0233963, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32530961

RESUMO

Eclipta alba L., also known as false daisy, is well known and commercially attractive plant with excellent hepatotoxic and antidiabetic activities. Light is considered a key modulator in plant morphogenesis and survival by regulating important physiological cascades. Current study was carried out to investigate growth and developmental aspects of E. alba under differential effect of multispectral lights. In vitro derived callus culture of E. alba was exposed to multispectral monochromatic lights under controlled aseptic conditions. Maximum dry weight was recorded in culture grown under red light (11.2 g/L) whereas negative effect was observed under exposure of yellow light on callus growth (4.87 g/L). Furthermore, red light significantly enhanced phenolics and flavonoids content (TPC: 57.8 mg/g, TFC: 11.1 mg/g) in callus cultures compared to rest of lights. HPLC analysis further confirmed highest accumulation of four major compounds i.e. coumarin (1.26 mg/g), eclalbatin (5.00 mg/g), wedelolactone (32.54 mg/g) and demethylwedelolactone (23.67 mg/g) and two minor compounds (ß-amyrin: 0.38 mg/g, luteolin: 0.39 mg/g) in red light treated culture whereas stigmasterol was found optimum (0.22 mg/g) under blue light. In vitro based biological activities including antioxidant, antidiabetic and lipase inhibitory assays showed optimum values in cultures exposed to red light, suggesting crucial role of these phytochemicals in the enhancement of the therapeutic potential of E. alba. These results clearly revealed that the use of multispectral lights in in vitro cultures could be an effective strategy for enhanced production of phytochemicals.


Assuntos
Antioxidantes/metabolismo , Eclipta/metabolismo , Eclipta/efeitos da radiação , Hipoglicemiantes/metabolismo , Compostos Fitoquímicos/metabolismo , Antioxidantes/química , Cumarínicos/metabolismo , Eclipta/crescimento & desenvolvimento , Flavonoides/metabolismo , Hipoglicemiantes/química , Luz , Fenóis/metabolismo , Compostos Fitoquímicos/química , Metabolismo Secundário/efeitos da radiação , Técnicas de Cultura de Tecidos
5.
Gene ; 756: 144920, 2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-32593720

RESUMO

Basic helix-loop-helix (bHLH) transcription factors play essential roles in myriad regulatory processes, including secondary metabolism. In this study with Salvia miltiorrhiza, we isolated and characterized SmbHLH53, which encodes a bHLH family member. Expression of this gene was significantly induced by wounding and multiple hormones, including methyl jasmonic acid; transcript levels were highest in the leaves and roots. Phylogenetic analysis indicated that SmbHLH53 clusters withAtbHLH17 and AtbHLH13, two negative regulators of jasmonate (JA) responses, and is localized in the nucleus and cell membrane. Yeast two-hybrid and bimolecular fluorescent complementation assays indicated that SmbHLH53 forms a homodimer as well as a heterodimer with SmbHLH37. It also interacts with both SmJAZs1/3/8 and SmMYC2, the core members of the JA signal pathway. Unexpectedly, we noted that overexpression of SmbHLH53 did not significantly influence the concentrations of rosmarinic acid and salvianolic acid B in transgenic plants. Results from yeast one-hybrid assays showed that SmbHLH53 binds to the promoters of SmTAT1, SmPAL1, and Sm4CL9, the key genes for enzymes in the pathway for phenolic acid synthesis. Assays of transient transcriptional activity demonstrated that SmbHLH53 represses the promoter of SmTAT1 while activating the promoter of Sm4CL9. Thus, the present work revealed that SmbHLH53 may play dual roles in regulating the genes for enzymes in the pathway for Sal B biosynthesis.


Assuntos
Benzofuranos/metabolismo , Salvia miltiorrhiza/genética , Salvia miltiorrhiza/metabolismo , Transdução de Sinais , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/análise , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Vias Biossintéticas , Núcleo Celular/química , Ciclopentanos/metabolismo , Oxilipinas/metabolismo , Filogenia , Proteínas de Plantas/análise , Proteínas de Plantas/metabolismo , Regiões Promotoras Genéticas , Mapas de Interação de Proteínas , Multimerização Proteica , Salvia miltiorrhiza/enzimologia , Metabolismo Secundário
6.
Zhongguo Zhong Yao Za Zhi ; 45(9): 2002-2008, 2020 May.
Artigo em Chinês | MEDLINE | ID: mdl-32495545

RESUMO

This paper summarized the effects of ecological planting on secondary metabolism firstly and pointed out that ecological planting can increase the content of secondary metabolites in plants, especially the content of defensive secondary metabolites. The possible mechanism was analyzed subsequently. Then, we reviewed the induction and utilization of secondary metabolism in the ecological planting of Chinese materia medica from the perspectives of biological control of pests and diseases, promotion of beneficial microorganism accumulation, optimization of mixed planting, regulation of no-tillage and straw cover. In this article, we pointed out that paying close attention to secondary metabolism is the most important feature of ecological planting of Chinese materia medica. Ecological planting can promote the accumulation of secondary metabolites of Chinese materia medica which means can improve the quality of Chinese materia medica, beneficial to the prevention and control of diseases, insects and weeds. Furthermore, lacking of systemic researches,the extensive verifications and systematic in-depth researches on the ecological planting of Chinese materia medica should be carry out urgently.


Assuntos
Medicamentos de Ervas Chinesas , Materia Medica , Plantas Medicinais , Medicina Tradicional Chinesa , Metabolismo Secundário
7.
Zhongguo Zhong Yao Za Zhi ; 45(9): 2009-2016, 2020 May.
Artigo em Chinês | MEDLINE | ID: mdl-32495546

RESUMO

Numerous studies showed that the growth of medicinal plants in their native areas was simultaneously affected by abiotic stress combinations. Compared with single stress, plants have unique responses to a combination of different abiotic stresses and cannot be inferred directly from plants' responses to each individual stress. The effect of combined stresses on plants usually has three types of synergistic antagonism or independence. The secondary metabolism in the process of medicinal plant stress combination response also played a vital role, and environmental stresses can spur the accumulation of secondary metabolites, but under the stress combination, plants induce specific gene expression of key enzymes on secondary metabolic pathways, in turn, the accumulation of secondary metabolites against stress is formed. When plants are subjected to stress combination, the interaction of multiple signaling pathways makes it highly complex for plants to respond to stress combination. This paper summarized the effects of stress combination on physiological and secondary metabolism of medicinal plants, and discussed the related physiological, biochemical and molecular mechanisms. It provides theoretical basis for improving the adaptability of medicinal plants to adversity, improving the quality of Chinese medicinal materials, and further optimizing the cultivation of medicinal plants.


Assuntos
Plantas Medicinais , Regulação da Expressão Gênica de Plantas , Redes e Vias Metabólicas , Metabolismo Secundário , Estresse Fisiológico
8.
Food Chem ; 330: 127268, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32540519

RESUMO

Essential oils (EOs) are natural, volatile and aromatic liquids extracted from special plants. EOs are complex mixture of secondary metabolites (terpenes, phenolic compounds, alcohol). EOs possess a wide range of biological activities including antioxidant, antimicrobial and anti-inflammatory ones. Particularly, EOs exhibit pronounced antibacterial and food preservative properties that represent a real potential for the food industry. Numerous EOs have the potential to be used as a food preservative for meat and meat products, vegetables and fruits as well as for dairy products. The main obstacles for using EOs as food preservatives are their safety limits, marked organoleptic effects and possible contamination by chemical products such as pesticides. This review aims to provide an overview of current knowledge about EOs food preservative properties with special emphasis on their antibacterial activities and to support their uses as natural, eco-friendly, safe and easily biodegradable agents for food preservation.


Assuntos
Conservação de Alimentos/métodos , Conservantes de Alimentos/química , Conservantes de Alimentos/farmacologia , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Antibacterianos/química , Antibacterianos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Inocuidade dos Alimentos , Frutas/química , Humanos , Carne , Produtos da Carne , Metabolismo Secundário , Terpenos/análise , Verduras
9.
Ecotoxicol Environ Saf ; 200: 110720, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32470680

RESUMO

Acid rain is a widespread environmental issue intensely affecting normal plant growth of crops. Melatonin is well known pleiotropic molecule which improves abiotic and biotic stress tolerance of plants through physiological and molecular mediation. However, the impact of exogenous melatonin on molecular activities under acid rain conditions in plants has never been studied. The objective of the study is to expose the possible role of exogenous melatonin on physiological and molecular changes against acid rain stress in tomato. Transcriptome profile through RNA-sequence analysis identified 1228, 1120 and 1537 differentially expressed genes (DEGs) in control plant (Ctr) vs simulated acid rain stressed plant (P25) comparison, control plant vs melatonin treatment in simulated acid rain stressed plant (P25M) comparison and P25 vs P25M comparison, respectively. Among them, 152 differentially expressed genes (DEGs) were commonly expressed and the expression of secondary metabolites related gene was noticeably observed in all comparison. Moreover, transcript families such as ERF, WRKY, MYB and bZIP related gene accounted more in all treatment comparison. The RNA-sequence and qPCR results indicated that exogenous melatonin is closely associated with acid rain stress moderator and might be involved in alteration of differentially expressed genes (DEGs), biosynthesis of plant secondary metabolites and transcriptional factor encoding genes expression which might have potential application against environmental hazardous conditions.


Assuntos
Chuva Ácida/efeitos adversos , Lycopersicon esculentum/efeitos dos fármacos , Melatonina/farmacologia , Fatores de Transcrição/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Lycopersicon esculentum/genética , Lycopersicon esculentum/metabolismo , Metabolismo Secundário/efeitos dos fármacos , Metabolismo Secundário/genética , Análise de Sequência de RNA , Estresse Fisiológico , Fatores de Transcrição/genética , Transcriptoma/efeitos dos fármacos
10.
Ecotoxicol Environ Saf ; 200: 110736, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32450438

RESUMO

As an effective neonicotinoid insecticide, imidacloprid (IMI) has been widely used in crop production, but its residue affects normal plant growth. Selenium (Se) is a non-essential mineral nutrient in higher plants, that acts as the active centre of glutathione peroxidase (GSH-Px), which removes harmful peroxides. In this study, we investigated the mechanism by which selenium improves the growth status of IMI-treated garlic plants through analyses of apparent morphology and antioxidant enzyme activity as well as the dynamic changes in nutrients and metabolites in the plants. The results showed that 80 µg/kg Na2SeO3 had a strong effect on alleviating the damage in garlic plants exposed to IMI (1.2 mg/kg) by increasing the absorption of mineral elements to enhance the synthesis of chlorophyll and antioxidant enzymes. A nontarget metabolomics analysis based on gas chromatography-mass spectrometry (GC-MS) indicated that the addition of Na2SeO3 to IMI-treated garlic could reconstruct the plant metabolic distribution by enhancing the nitrogen and indole metabolism, maintaining lower concentrations of secondary metabolites and maintaining the balance of the plant energy metabolism. Our study provides novel insights into the molecular mechanisms by which garlic plants responds to IMI exposure and suggests the use of selenium with IMI-contaminated plants as a solution for the advancement of sustainable agricultural pesticide use.


Assuntos
Alho/efeitos dos fármacos , Inseticidas/toxicidade , Neonicotinoides/toxicidade , Nitrocompostos/toxicidade , Selenito de Sódio/farmacologia , Antioxidantes/metabolismo , Clorofila/metabolismo , Metabolismo Energético/efeitos dos fármacos , Alho/enzimologia , Alho/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Indóis/metabolismo , Nitrogênio/metabolismo , Metabolismo Secundário/efeitos dos fármacos
11.
PLoS One ; 15(5): e0232172, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32365106

RESUMO

BACKGROUND: The fungal toxin acts as effective, low-cost chemical substances for pest control worldwide and also an alternative to synthetic insecticides. This study assessed the larvicidal potential of Metarhizium anisopliae fungi derived metabolites against Aedes aegypti, Anopheles stephensi, Culex quinquefasciatus and non-targeted organisms at 24hr post treatment. METHOD: Isolation of entomopathogenic fungi M. anisopliae from natural traps confirmed by using 18s rDNA biotechnological tools. Crude extracts from M. anisopliae solvent extraction and their secondary metabolites were bio-assayed following WHO standard procedures against Ae. aegypti, An. stephensi and Cx. quinquefasciatus, Artemia nauplii, Eudrilus eugeniae, and Solanum lycopersicum after 24 hr exposure. Histopathological analysis of E. eugeniae treated with fungi metabolites toxicity compared to those treated with Monocrotophos after 24hrpost-treatment. M. anisopliae metabolites were characterized using GC-MS and FT-IR analysis. RESULTS: The larvicidal activity was recorded in highest concentration of 75µg/ml, with 85%, 97% and 89% mortality in Ae. aegypti, An. stephensi and Cx. quinquefasciatus respectively. M. anisopliae metabolites produced LC50 values in Ae. aegypti, 59.83µg/ml, in An. stephensi, 50.16µg/ml and in Cx. quinquefasciatus, 51.15µg/ml respectively. M. anisopliae metabolites produced lower toxic effects on A. nauplii, LC50 values were, 54.96µg/ml respectively. Bio-indicator toxicity results show 18% and 58% mortality was recorded in E. eugeniae and A. nauplii and also there is no phytotoxicity that was observed on S. lycopersicum L. under semi-field condition. E. eugeniae histopathological studies shows fungal metabolites showed lower sub-lethal effects compared to synthetic chemical pesticide at 24hrs of the treatment. The GC-MS and FT-IR analysis identified five major components of active ingredients. CONCLUSION: Findings of this study indicate that, M. anisopliae ethyl acetate derived secondary metabolites are effective against larvae of Ae. aegypti, An. stephensi and Cx. quinquefasciatus mosquito species, lower toxicity effects were observed on non-target organisms such as, Artemia nauplii, Eudrilus eugeniae as well as, no toxicity effect were observed on Solanum lycopersicum. Further research should be conducted in laboratory for separation of single pure molecule and be tested semifield conditions.


Assuntos
Aedes/efeitos dos fármacos , Anopheles/efeitos dos fármacos , Produtos Biológicos/farmacologia , Culex/efeitos dos fármacos , Metarhizium/química , Animais , Produtos Biológicos/química , DNA Fúngico/genética , DNA Ribossômico/genética , Cromatografia Gasosa-Espectrometria de Massas , Controle de Insetos , Larva/efeitos dos fármacos , Metarhizium/genética , Metarhizium/isolamento & purificação , Monocrotofós/farmacologia , RNA Ribossômico 18S/genética , Metabolismo Secundário , Espectroscopia de Infravermelho com Transformada de Fourier
12.
PLoS One ; 15(5): e0227396, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32469865

RESUMO

Elsinoë fawcettii, a necrotrophic fungal pathogen, causes citrus scab on numerous citrus varieties around the world. Known pathotypes of E. fawcettii are based on host range; additionally, cryptic pathotypes have been reported and more novel pathotypes are thought to exist. E. fawcettii produces elsinochrome, a non-host selective toxin which contributes to virulence. However, the mechanisms involved in potential pathogen-host interactions occurring prior to the production of elsinochrome are unknown, yet the host-specificity observed among pathotypes suggests a reliance upon such mechanisms. In this study we have generated a whole genome sequencing project for E. fawcettii, producing an annotated draft assembly 26.01 Mb in size, with 10,080 predicted gene models and low (0.37%) coverage of transposable elements. A small proportion of the assembly showed evidence of AT-rich regions, potentially indicating genomic regions with increased plasticity. Using a variety of computational tools, we mined the E. fawcettii genome for potential virulence genes as candidates for future investigation. A total of 1,280 secreted proteins and 276 candidate effectors were predicted and compared to those of other necrotrophic (Botrytis cinerea, Parastagonospora nodorum, Pyrenophora tritici-repentis, Sclerotinia sclerotiorum and Zymoseptoria tritici), hemibiotrophic (Leptosphaeria maculans, Magnaporthe oryzae, Rhynchosporium commune and Verticillium dahliae) and biotrophic (Ustilago maydis) plant pathogens. Genomic and proteomic features of known fungal effectors were analysed and used to guide the prioritisation of 120 candidate effectors of E. fawcettii. Additionally, 378 carbohydrate-active enzymes were predicted and analysed for likely secretion and sequence similarity with known virulence genes. Furthermore, secondary metabolite prediction indicated nine additional genes potentially involved in the elsinochrome biosynthesis gene cluster than previously described. A further 21 secondary metabolite clusters were predicted, some with similarity to known toxin producing gene clusters. The candidate virulence genes predicted in this study provide a comprehensive resource for future experimental investigation into the pathogenesis of E. fawcettii.


Assuntos
Ascomicetos/genética , Citrus/microbiologia , Genoma Fúngico/genética , Anotação de Sequência Molecular , Ascomicetos/patogenicidade , Parede Celular/enzimologia , Mineração de Dados , Família Multigênica/genética , Metabolismo Secundário/genética
13.
Planta Med ; 86(13-14): 997-1008, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32294787

RESUMO

Medicinal plants of the genus Hypericum are rich sources of bioactive naphthodianthrones, which are unique in the plant kingdom, but quite common in fungal endophytes. Cultivable endophytic fungi were isolated from 14 different Hypericum spp. originating from seeds grown under in vitro conditions and further acclimated to outdoor conditions. Among 37 fungal isolates yielded from the aerial and underground plant organs, 25 were identified at the species level by the fungal barcode marker internal transcribed spacer rDNA and protein-coding gene region of tef1α. Ten of them were isolated from Hypericum spp. for the first time. The axenic cultures of the isolated endophytes were screened for the production of extracellular enzymes, as well as bioactive naphthodianthrones and their putative precursors by Bornträger's test and HPLC-HRMS. Traces of naphthodianthrones and their intermediates, emodin, emodin anthrone, skyrin, or pseudohypericin, were detected in the fungal mycelia of Acremonium sclerotigenum and Plectosphaerella cucumerina isolated from Hypericum perforatum and Hypericum maculatum, respectively. Traces of emodin, hypericin, and pseudohypericin were released in the broth by Scedosporium apiospermum, P. cucumerina, and Fusarium oxysporum during submerged fermentation. These endophytes were isolated from several hypericin-producing Hypericum spp. Taken together, our results reveal the biosynthetic potential of cultivable endophytic fungi harbored in Hypericum plants as well as evidence of the existence of remarkable plant-endophyte relationships in selected non-native ecological niches. A possible role of the extracellular enzymes in plant secondary metabolism is discussed.


Assuntos
Hypericum , Plantas Medicinais , Endófitos/genética , Fungos/genética , Metabolismo Secundário , Sementes
14.
Zhongguo Zhong Yao Za Zhi ; 45(2): 321-330, 2020 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-32237314

RESUMO

Atropa belladonna seedlings were used as experimental materials and cultivated by soil culture method. Different concentrations(0,0.05,0.1,0.2,0.5 mmol·L~(-1))of NO donor sodium nitroprusside(SNP) were sprayed on the leaves. The effects of different concentrations of SNP and different treatment time(4,8,12,16 d) on nitrogen metabolism, secondary metabolite content, precursor content of tropane alkaloid synthesis pathway and expression of key enzyme genes under 100 mmol·L~(-1) NaCl stress were studied. The results showed that with the prolongation of salt stress, the nitrogen metabolism and the accumulation of secondary metabolites of A. belladonna were inhibited to some extent. After treatment with different concentrations of exogenous SNP, the ammonium nitrogen content decreased dramatically, and the contents of nitrate nitrogen, free amino acid, soluble protein and the activities of key enzymes of nitrogen metabolism(NR, GS, GDH) were all greatly improved; the contents of precursor amino acids(ornithine, arginine) and polyamines(Put, Spd, Spm) in the secondary metabolic pathway have increased to varying degrees. The qRT-PCR analysis showed that exogenous SNP treatment can effectively promote the high expression of key enzyme genes PMT, TRⅠ and H6H in the secondary metabolic pathway of A. belladonna, and the production of hyoscyamine and scopolamine were increased notably. In summary, the application of appropriate concentration of SNP can effectively alleviate the inhibition of salt stress on the nitrogen metabolism and secondary metabolism of Atropa belladonna, and enhance its salt tolerance. Overall, 0.1 mmol·L~(-1) and 0.2 mmol·L~(-1) SNP treatment achieved the most remarkable effect.


Assuntos
Atropa belladonna/metabolismo , Hiosciamina/análise , Nitrogênio/metabolismo , Escopolamina/análise , Nitroprussiato , Metabolismo Secundário , Cloreto de Sódio , Estresse Fisiológico
15.
Zhongguo Zhong Yao Za Zhi ; 45(6): 1272-1278, 2020 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-32281336

RESUMO

Molecular biology is a new subject that clarifies the phenomena and nature of life at the molecular level. Its development provides new biotechnology and methods for the study of traditional pharmacognosy. The formation of molecular biology has brought the development of pharmacognosy into a new era of gene research. Lonicerae Japonicae Flos is a classical Chinese medicine. Many scholars of home and abroad have carried out relevant studies on its molecular biology on the basis of the in-depth study with traditional methods, and have achieved certain results. In order to provide references on the method, technical for promoting the modernization of Lonicerae Japonicae Flos, and the development, protection, and utilization of other traditional Chinese medicine resources. This article summarized the application status of molecular biology methods and techniques on the identification, biosynthesis of active constituents, and molecular mechanism of secondary metabolite under stress conditions of Lonicerae Japonicae Flos in recent years. In hybridization technology of tag(RFLP), molecular markers based on PCR(RAPD, AFLP, SSR and ISSR), based on DNA sequence analysis of SNP and DNA barcode for the variety identification, diagnosis, identification of Lonicerae Japonicae Flos, and so forth in detail. At the same time, it is proposed that multi-omics technology can be used to build systems biology technology and platforms, and establish related models of secondary metabolite biosynthesis, so as to deepen acknowledge the molecular mechanism of the active component biosynthesis of Lonicerae Japonicae Flos and the accumulation of metabolites, life activities of other medicinal plants under adverse environment, then to regulate them.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Lonicera/química , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Cromatografia Líquida de Alta Pressão , Código de Barras de DNA Taxonômico , Medicina Tradicional Chinesa , Repetições de Microssatélites , Plantas Medicinais/química , Polimorfismo de Fragmento de Restrição , Polimorfismo de Nucleotídeo Único , Técnica de Amplificação ao Acaso de DNA Polimórfico , Metabolismo Secundário
16.
Zhongguo Zhong Yao Za Zhi ; 45(6): 1368-1373, 2020 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-32281350

RESUMO

Eight compounds,(R)-2-[5-(methoxycarbonyl)-4-methyl-6-oxo-3,6-dihydro-2H-pyran-2-yl]acetic acid(1),(3S,4R)-3,4-dihydro-3,4-epoxy-5-hydroxynaphthalen-1(2H)-one(2),(-)-mitorubrinol(3),(-)-mitorubrin(4),(±)-asperlone A(5), terreusinone(6), verrucisidinol(7) and cerebroside C(8) were isolated from the endophytic fungus Talaromyces purpurogenus by using various column chromatographic techniques. Their structures were identified by NMR, MS, CD and optical rotation. Compounds 1 and 2 were new compounds. Their anti-diabetic activities in vitro were evaluated, and compound 1 showed moderate inhibitory activity toward XOD at 10 µmol·L~(-1) with the inhibition rate of 69.9%.


Assuntos
Talaromyces/química , Tylophora/microbiologia , Endófitos/química , Hipoglicemiantes/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Metabolismo Secundário , Xantina Oxidase/antagonistas & inibidores
17.
Gene ; 744: 144626, 2020 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-32224272

RESUMO

Polygonatum odoratum (Mill.) Druce is a well-known traditional Chinese herb. Polysaccharides are major bioactive components of Polygonatum odoratum, which can improve immunity, and are used to treat rheumatic heart disease, cardiovascular disease, and diabetes. This study identified potential genes and transcription factors (TFs) that regulate polysaccharide synthesis in Polygonatum odoratum (Mill.) Druce using RNA sequencing data from leaf, stem, and rhizome tissues. 76,714 unigenes were annotated in public databases. Analysis of KEGG annotations identified 18 key enzymes responsible for polysaccharide biosynthesis and the most of the upregulated expressed unigenes were enriched in rhizome tissue compared with leaf or stem tissue. 73 TFs involved in polysaccharide synthesis were predicted. In addition, key enzyme genes were verified by quantitative real-time PCR. This study substantially enlarged the public transcriptome datasets of this species, and provided insight into detection of novel genes involved in synthesis of polysaccharides and other secondary metabolites.


Assuntos
Polygonatum/genética , Polissacarídeos/biossíntese , Transcriptoma , Expressão Gênica , Genes de Plantas , Folhas de Planta/genética , Folhas de Planta/metabolismo , Caules de Planta/genética , Caules de Planta/metabolismo , Polygonatum/enzimologia , Polygonatum/metabolismo , Polissacarídeos/metabolismo , RNA-Seq , Rizoma/genética , Rizoma/metabolismo , Metabolismo Secundário/genética , Fatores de Transcrição/metabolismo , beta-Frutofuranosidase/química
18.
Nat Commun ; 11(1): 1910, 2020 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-32313046

RESUMO

Yield losses caused by fungal pathogens represent a major threat to global food production. One of the most devastating fungal wheat pathogens is Zymoseptoria tritici. Despite the importance of this fungus, the underlying mechanisms of plant-pathogen interactions are poorly understood. Here we present a conceptual framework based on coinfection assays, comparative metabolomics, and microbiome profiling to study the interaction of Z. tritici in susceptible and resistant wheat. We demonstrate that Z. tritici suppresses the production of immune-related metabolites in a susceptible cultivar. Remarkably, this fungus-induced immune suppression spreads within the leaf and even to other leaves, a phenomenon that we term "systemic induced susceptibility". Using a comparative metabolomics approach, we identify defense-related biosynthetic pathways that are suppressed and induced in susceptible and resistant cultivars, respectively. We show that these fungus-induced changes correlate with changes in the wheat leaf microbiome. Our findings suggest that immune suppression by this hemibiotrophic pathogen impacts specialized plant metabolism, alters its associated microbial communities, and renders wheat vulnerable to further infections.


Assuntos
Ascomicetos/metabolismo , Interações Hospedeiro-Patógeno/imunologia , Interações Hospedeiro-Patógeno/fisiologia , Metaboloma , Microbiota/fisiologia , Imunidade Vegetal/fisiologia , Ascomicetos/patogenicidade , Benzoxazinas/metabolismo , Vias Biossintéticas , Coinfecção , Doenças das Plantas/microbiologia , Folhas de Planta/microbiologia , Metabolismo Secundário , Triticum/imunologia , Triticum/microbiologia
19.
Nat Commun ; 11(1): 1867, 2020 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-32313070

RESUMO

Plant halogenated natural products are rare and harbor various interesting bioactivities, yet the biochemical basis for the involved halogenation chemistry is unknown. While a handful of Fe(II)- and 2-oxoglutarate-dependent halogenases (2ODHs) have been found to catalyze regioselective halogenation of unactivated C-H bonds in bacteria, they remain uncharacterized in the plant kingdom. Here, we report the discovery of dechloroacutumine halogenase (DAH) from Menispermaceae plants known to produce the tetracyclic chloroalkaloid (-)-acutumine. DAH is a 2ODH of plant origin and catalyzes the terminal chlorination step in the biosynthesis of (-)-acutumine. Phylogenetic analyses reveal that DAH evolved independently in Menispermaceae plants and in bacteria, illustrating an exemplary case of parallel evolution in specialized metabolism across domains of life. We show that at the presence of azide anion, DAH also exhibits promiscuous azidation activity against dechloroacutumine. This study opens avenues for expanding plant chemodiversity through halogenation and azidation biochemistry.


Assuntos
Alcaloides/biossíntese , Compostos Ferrosos/metabolismo , Hidrolases/metabolismo , Ácidos Cetoglutáricos/metabolismo , Menispermaceae/metabolismo , Compostos de Espiro/metabolismo , Alcaloides/química , Alcaloides/genética , Bactérias/metabolismo , Biocatálise , Genes de Plantas/genética , Halogenação , Menispermaceae/embriologia , Menispermaceae/genética , Mutagênese , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas Recombinantes , Metabolismo Secundário/genética , Alinhamento de Sequência , Compostos de Espiro/química , Transcriptoma
20.
Proc Natl Acad Sci U S A ; 117(16): 8850-8858, 2020 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-32265283

RESUMO

Closthioamide (CTA) is a rare example of a thioamide-containing nonribosomal peptide and is one of only a handful of secondary metabolites described from obligately anaerobic bacteria. Although the biosynthetic gene cluster responsible for CTA production and the thioamide synthetase that catalyzes sulfur incorporation were recently discovered, the logic for peptide backbone assembly has remained a mystery. Here, through the use of in vitro biochemical assays, we demonstrate that the amide backbone of CTA is assembled in an unusual thiotemplated pathway involving the cooperation of a transacylating member of the papain-like cysteine protease family and an iteratively acting ATP-grasp protein. Using the ATP-grasp protein as a bioinformatic handle, we identified hundreds of such thiotemplated yet nonribosomal peptide synthetase (NRPS)-independent biosynthetic gene clusters across diverse bacterial phyla. The data presented herein not only clarify the pathway for the biosynthesis of CTA, but also provide a foundation for the discovery of additional secondary metabolites produced by noncanonical biosynthetic pathways.


Assuntos
Antibacterianos/metabolismo , Bactérias Anaeróbias/enzimologia , Proteínas de Bactérias/metabolismo , Cisteína Endopeptidases/metabolismo , Biossíntese de Peptídeos Independentes de Ácido Nucleico/genética , Tioamidas/metabolismo , Trifosfato de Adenosina/metabolismo , Bactérias Anaeróbias/genética , Proteínas de Bactérias/genética , Sítios de Ligação , Vias Biossintéticas/genética , Biologia Computacional , Cisteína Endopeptidases/genética , Genes Bacterianos , Família Multigênica , Metabolismo Secundário/genética
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