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1.
PLoS One ; 15(8): e0235355, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32817671

RESUMO

The Arbuscular mycorrhizal fungi (AMF) (Funneliformis mosseae), are the most widely distributed symbiont assisting plants to overcome counteractive environmental conditions. In order to improve the sustainability and the activity of AMF, the use of nanotechnology was important. The main objective of this study was to investigate the effect of titanium dioxide nanoparticles (TiO2NPs) on the activity of AMF in common bean roots as well as its activity under salinity stress using morphological and molecular methods. The activity of AMF colonization has increased in the presence of TiO2NPs especially for arbuscule activity (A%), which increased three times with the presence of TiO2NPs. The improvement rate of Funneliformis mosseae on plant growth increased from 180% to 224% of control at the lowest level of salinity and increased from 48% to 130% at higher salinity level, respectively. The AMF dependencies for plant dry biomass increased in the presence of TiO2NPs from 277% in the absence of salinity to 465 and 883% % at low and high salinity levels, respectively. The presence of AMF co-inoculated with TiO2NPs resulted in increasing the salinity tolerance of plants at all levels and reached 110% at salinity level of 100 mM NaCl. Quantitative colonization methods showed that the molecular intensity ratio and the relative density of paired inocula AMF Nest (NS) or chitin synthases gene (Chs) with TiO2NPs were higher significantly P.>0.05 than single inoculants of AMF gene in roots under the presence or the absence of salinity by about two folds and about 40%. Hence, the positive effect of TiO2NPs was confined to its effect on AMF not on bean plants itself.


Assuntos
Ascomicetos/patogenicidade , Nanopartículas Metálicas/química , Phaseolus/microbiologia , Tolerância ao Sal , Ascomicetos/efeitos dos fármacos , Ascomicetos/metabolismo , Quitina Sintase/genética , Quitina Sintase/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Nanopartículas Metálicas/microbiologia , Phaseolus/metabolismo , Simbiose , Titânio/química , Titânio/farmacologia
2.
PLoS One ; 15(7): e0229192, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32701945

RESUMO

Tall fescue (Lolium arundinaceum) is a widely used forage grass which shares a symbiosis with the endophytic fungus Epichloë coenophiala. The endophyte produces an alkaloid toxin that provides herbivory, heat and drought resistance to the grass, but can cause fescue toxicosis in grazing livestock. Fescue toxicosis can lead to reduced weight gain and milk yields resulting in significant losses to the livestock industry. The objective of this study was to identify bacterial and fungal communities associated with fescue toxicosis tolerance. In this trial, 149 Angus cows across two farms were continuously exposed to toxic, endophyte-infected, fescue for a total of 13 weeks. Of those 149 cows, 40 were classified into either high (HT) or low (LT) tolerance groups according to their growth performance (weight gain). 20 HT and 20 LT cattle balanced by farm were selected for amplicon sequencing to compare the fecal microbiota of the two tolerance groups. This study reveals significantly (q<0.05) different bacterial and fungal microbiota between HT and LT cattle, and indicates that fungal phylotypes may be important for an animal's response to fescue toxicosis: We found that fungal phylotypes affiliating to the Neocallimastigaceae, which are known to be important fiber-degrading fungi, were consistently more abundant in the HT cattle. Whereas fungal phylotypes related to the genus Thelebolus were more abundant in the LT cattle. This study also found more pronounced shifts in the microbiota in animals receiving higher amounts of the toxin. We identified fungal phylotypes which were consistently more abundant either in HT or LT cattle and may thus be associated with the respective animal's response to fescue toxicosis. Our results thus suggest that some fungal phylotypes might be involved in mitigating fescue toxicosis.


Assuntos
Epichloe/metabolismo , Microbioma Gastrointestinal , Lolium/microbiologia , Animais , Ascomicetos/isolamento & purificação , Ascomicetos/metabolismo , Bovinos , Análise Discriminante , Alcaloides de Claviceps/análise , Alcaloides de Claviceps/toxicidade , Fezes/microbiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Neocallimastigales/isolamento & purificação , Neocallimastigales/metabolismo , Simbiose , Toxinas Biológicas/análise , Toxinas Biológicas/toxicidade
3.
J Genet ; 992020.
Artigo em Inglês | MEDLINE | ID: mdl-32529987

RESUMO

Powdery mildew (Blumeria graminis f. sp. Tritici, (Bgt)) is an important worldwide fungal foliar disease of wheat (Triticum aestivum) responsible for severe yield losses. The development of resistance genes and dissection of the resistance mechanism will therefore be beneficial in wheat breeding. The Bgt resistance gene PmAS846 was transferred to the hexaploid wheat lines N9134 from Triticum dicoccoides, and it is still one of the most effective resistance genes. Here, by RNA sequencing, we identified three co-expressed gene modules using pairwise comparisons and weighted gene co-expression network analysis during wheat-Bgt interactions compared with mock-infected plants. Hub genes of stress-specific modules were significantly enriched in spliceosomes, phagosomes, the mRNA surveillance pathway, protein processing in the endoplasmic reticulum, and endocytosis. Induced module genes located on chromosome 5BL were selected to construct a protein-protein interaction network. Several proteins were predicted as the key hub node, including Hsp70, DEAD/DEAH box RNA helicase PRH75, elongation factor EF-2, cell division cycle 5, ARF guanine-nucleotide exchange factor GNOM-like, and protein phosphatase 2C 70 protein, which interacted with several disease resistance proteins such as RLP37, RPP13 and RPS2 analogues. Gene ontology enrichment results showed that wheat could activate binding functional genes via an mRNA transcription mechanism in response to Bgt stress. Of these node genes, GNOM-like, PP2C isoform X1 and transmembrane 9 superfamily member 9 were mapped onto the genetic fragment of PmAS846 with a distance of 4.8 Mb. This work provides the foundations for understanding the resistance mechanism and cloning the resistance gene PmAS846.


Assuntos
Ascomicetos/metabolismo , Resistência à Doença/genética , Estresse Fisiológico , Triticum/genética , Triticum/metabolismo , Análise de Sequência de RNA
4.
PLoS Pathog ; 16(6): e1008652, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32574207

RESUMO

Plants trigger immune responses upon recognition of fungal cell wall chitin, followed by the release of various antimicrobials, including chitinase enzymes that hydrolyze chitin. In turn, many fungal pathogens secrete LysM effectors that prevent chitin recognition by the host through scavenging of chitin oligomers. We previously showed that intrachain LysM dimerization of the Cladosporium fulvum effector Ecp6 confers an ultrahigh-affinity binding groove that competitively sequesters chitin oligomers from host immune receptors. Additionally, particular LysM effectors are found to protect fungal hyphae against chitinase hydrolysis during host colonization. However, the molecular basis for the protection of fungal cell walls against hydrolysis remained unclear. Here, we determined a crystal structure of the single LysM domain-containing effector Mg1LysM of the wheat pathogen Zymoseptoria tritici and reveal that Mg1LysM is involved in the formation of two kinds of dimers; a chitin-dependent dimer as well as a chitin-independent homodimer. In this manner, Mg1LysM gains the capacity to form a supramolecular structure by chitin-induced oligomerization of chitin-independent Mg1LysM homodimers, a property that confers protection to fungal cell walls against host chitinases.


Assuntos
Ascomicetos/química , Quitina/química , Proteínas Fúngicas/química , Hifas/química , Multimerização Proteica , Ascomicetos/genética , Ascomicetos/metabolismo , Quitina/genética , Quitina/metabolismo , Cladosporium/química , Cladosporium/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Hifas/genética , Hifas/metabolismo , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Estrutura Quaternária de Proteína , Triticum/genética , Triticum/metabolismo , Triticum/microbiologia
5.
Nat Commun ; 11(1): 3090, 2020 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-32555161

RESUMO

Brassicales plants produce glucosinolates and myrosinases that generate toxic isothiocyanates conferring broad resistance against pathogens and herbivorous insects. Nevertheless, some cosmopolitan fungal pathogens, such as the necrotrophic white mold Sclerotinia sclerotiorum, are able to infect many plant hosts including glucosinolate producers. Here, we show that S. sclerotiorum infection activates the glucosinolate-myrosinase system, and isothiocyanates contribute to resistance against this fungus. S. sclerotiorum metabolizes isothiocyanates via two independent pathways: conjugation to glutathione and, more effectively, hydrolysis to amines. The latter pathway features an isothiocyanate hydrolase that is homologous to a previously characterized bacterial enzyme, and converts isothiocyanate into products that are not toxic to the fungus. The isothiocyanate hydrolase promotes fungal growth in the presence of the toxins, and contributes to the virulence of S. sclerotiorum on glucosinolate-producing plants.


Assuntos
Ascomicetos/enzimologia , Ascomicetos/metabolismo , Glucosinolatos/metabolismo , Glicosídeo Hidrolases/metabolismo , Glutationa/metabolismo , Glicosídeo Hidrolases/classificação , Glicosídeo Hidrolases/genética , Hidrólise , Isotiocianatos/metabolismo , Filogenia , Imunidade Vegetal/fisiologia
6.
Biofouling ; 36(3): 308-318, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32401558

RESUMO

In the present study, the composition of the extracellular matrix (ECM) of the biofilm formed by Scedosporium apiospermum, S. aurantiacum, S. minutisporum and Lomentospora prolificans on a polystyrene surface was investigated. Confocal laser scanning microscopy revealed a dense mycelial mass, with an ECM covering/interspersing the fungal cells and containing carbohydrate-rich molecules (e.g. glycoproteins) and extracellular DNA. The ECMs that were chemically extracted from mature biofilms formed by each of these fungi was predominantly composed of polysaccharides, followed by proteins, nucleic acids and sterols. In general, the amount of biofilm ECM was significantly greater in S. minutisporum and S. aurantiacum than in S. apiospermum and L. prolificans. Corroborating these results, the disarticulation of mature biofilms with enzymes, sodium metaperiodate and chelating agents occurred mainly in S. minutisporum and S. aurantiacum. Collectively, these results have revealed for the first time the composition of the ECM of the biofilms formed by Scedosporium/Lomentospora species and the role it plays in their architecture.


Assuntos
Ascomicetos/crescimento & desenvolvimento , Biofilmes/crescimento & desenvolvimento , Matriz Extracelular/metabolismo , Scedosporium/crescimento & desenvolvimento , Ascomicetos/metabolismo , Humanos , Microscopia Confocal , Poliestirenos/química , Scedosporium/metabolismo , Propriedades de Superfície
7.
Nat Commun ; 11(1): 2144, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32358542

RESUMO

The Saccharomycotina subphylum (budding yeasts) spans 400 million years of evolution and includes species that thrive in diverse environments. To study niche-adaptation, we identify changes in gene expression in three divergent yeasts grown in the presence of various stressors. Duplicated and non-conserved genes are significantly more likely to respond to stress than genes that are conserved as single-copy orthologs. Next, we develop a sorting method that considers evolutionary origin and duplication timing to assign an evolutionary age to each gene. Subsequent analysis reveals that genes that emerged in recent evolutionary time are enriched amongst stress-responsive genes for each species. This gene expression pattern suggests that budding yeasts share a stress adaptation mechanism, whereby selective pressure leads to functionalization of young genes to improve growth in adverse conditions. Further characterization of young genes from species that thrive in harsh environments can inform the design of more robust strains for biotechnology.


Assuntos
Saccharomycetales/metabolismo , Ascomicetos/genética , Ascomicetos/metabolismo , Biotecnologia/métodos , Genoma Fúngico/genética , Filogenia , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo
8.
Artigo em Inglês | MEDLINE | ID: mdl-32229427

RESUMO

Sclerotinia sclerotiorum is a necrotrophic phytopathogen that has been the subject of several scientific research efforts. Despite the numerous research efforts its proteome remains understudied. This study aimed to identify proteins produced by S. sclerotiorum, thereby increasing the current proteomic knowledge base. Total proteins were extracted from mycelia scraped from five-day old cultures of S. sclerotiorum. The extracted proteins were separated by sodium dodecyl polyacrylamide gel electrophoresis (SDS-PAGE) and were annotated using the AB Sciex TripleToF 6600 mass spectrometer. Exactly 1471 proteins were reproducibly present in all three replicates. All proteins detected were classified based on their molecular and biological functions. To the knowledge of the authors, this is the most comprehensive proteomic study on S. sclerotiorum (judging by the high number of proteins identified).


Assuntos
Ascomicetos/química , Proteínas Fúngicas/análise , Proteoma/análise , Ascomicetos/metabolismo , Dissulfetos/química , Eletroforese em Gel Bidimensional , Ensaios de Triagem em Larga Escala , Espectrometria de Massas , Micélio/química , Oxirredução , Proteômica
9.
Chemosphere ; 252: 126208, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32229362

RESUMO

Even though many fungi are known to degrade a range of organic chemicals and may be advantageous for targeting hydrophobic chemicals with low bioavailability due to their ability to secrete extracellular enzymes, fungi are not commonly leveraged in the context of bioremediation. Here we sought to examine the fungal microbiome (mycobiome) at a model creosote polluted site to determine if fungi were prevalent under high PAH contamination conditions as well as to identify potential mycostimulation targets. Several significant positive associations were detected between OTUs and mid-to high-molecular weight PAHs. Several OTUs were closely related to taxa that have previously been identified in culture-based studies as PAH degraders. In particular, members belonging to the Ascomycota phylum were the most diverse at higher PAH concentrations suggesting this phylum may be promising biostimulation targets. There were nearly three times more positive correlations as compared to negative correlations, suggesting that creosote-tolerance is more common than creosote-sensitivity in the fungal community. Future work including shotgun metagenomic analysis would help confirm the presence of specific degradation genes. Overall this study suggests that mycobiome and bacterial microbiome analyses should be performed in parallel to devise the most optimal in situ biostimulation treatment strategies.


Assuntos
Creosoto/análise , Locais de Resíduos Perigosos , Micobioma , Microbiologia do Solo , Poluentes do Solo/análise , Ascomicetos/metabolismo , Bactérias/metabolismo , Biodegradação Ambiental , Microbiota , Hidrocarbonetos Policíclicos Aromáticos/análise
10.
PLoS One ; 15(4): e0231453, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32298310

RESUMO

A laccase-producing ascomycete fungus was isolated from soil collected around the premises of a textile dye factory and identified as Nectriella pironii. Efficient laccase production was achieved via the synergistic action of 1 mM copper sulfate and ferulic acid. Extracts of rapeseed oil cake, grass hay, and leaf litter collected in a pocket urban park were used for enzyme production. The highest laccase activity (3,330 U/L) was observed in the culture grown on the leaf litter extract. This is the first report on biosynthesis of laccase by N. pironii. This is also the first study on utilization of naturally fallen park leaves as a substrate for fungal laccase production. The extracellular enzyme possessing laccase activity was purified to homogeneity by ion-exchange and gel filtration chromatographic techniques. The amino acid sequence of the protein revealed highest similarity to the laccase enzyme produced by Stachybotrys chartarum-and considerable homology to those produced by other fungal species. The purified laccase possessed a molecular mass of 50 kDa. The enzyme had an optimum pH of 2.0 or 6.0 and retained more than 50% of residual activity after 3 hours of incubation at pH 3.0-10.6 or 4.0-9.0 when 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid or 2,6-dimethoxyphenol, respectively, were used. Dithiothreitol, ß-mercaptoethanol, and sodium azide at 1 mM concentration strongly inhibited the laccase activity, while in the presence of 50 mM urea, the enzyme was found to retain 25% of its activity. The laccase was able to decolorize more than 80% of Indigo Carmine, Remazol Brilliant Blue R, Reactive Orange 16, and Acid Red 27 dyes within 1 h. The possibility of leaf litter use for the production of the laccase enzyme from N. pironii (IM 6443), exhibiting high pH stability and degradative potential, makes it a promising tool for use in different environmental and industrial operations.


Assuntos
Ascomicetos/enzimologia , Lacase/metabolismo , Parques Recreativos , Folhas de Planta/microbiologia , Ascomicetos/crescimento & desenvolvimento , Ascomicetos/metabolismo , Microbiologia do Solo
11.
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
12.
Food Microbiol ; 87: 103395, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31948636

RESUMO

Volatile compounds produced by L1 and L8 strains were assayed against mycelia and conidia growth of Monilinia laxa, M. fructicola, M. polystroma, and M. fructigena of stone fruits. Results showed that volatile metabolites inhibited significantly pathogens growth, in particular M. fructigena mycelium growth (70% by L1 and 50% by L8) and M. fructicola conidia germination (85% by L1 and 70% by L8) compared to the control. Moreover, the antagonistic activity was enhanced by the addition of asparagine (120 mg L-1) in the culture media composition. Synthetic pure compounds were tested in vitro on pathogens mycelial and conidia growth and their EC50 values were estimated, confirming 2-phenethyl as the most active compound. For this reason 2-phenethyl and VOCs of both yeast strains were assayed in vivo on cherry, peach, and apricot fruits. Regarding peach fruit, both treatments, yeasts and pure compounds, displayed the best inhibiting action against all the pathogens especially against M. laxa (100% by L1, 84% by L8 and 2-phenethyl). ATR/IR spectroscopy analysis showed how VOCs produced by both strains increase the fruit waxes complexity reducing the pathogens attack so playing an essential role in the antagonistic activity of both yeast strains and on fruit structural composition.


Assuntos
Ascomicetos/química , Fungicidas Industriais/farmacologia , Doenças das Plantas/microbiologia , Compostos Orgânicos Voláteis/farmacologia , Ascomicetos/crescimento & desenvolvimento , Ascomicetos/metabolismo , Frutas/microbiologia , Fungicidas Industriais/química , Fungicidas Industriais/metabolismo , Micélio/efeitos dos fármacos , Micélio/crescimento & desenvolvimento , Prunus persica/microbiologia , Esporos Fúngicos/efeitos dos fármacos , Esporos Fúngicos/crescimento & desenvolvimento , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/metabolismo
14.
Appl Biochem Biotechnol ; 190(1): 73-89, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31301009

RESUMO

Curvulamine, a novel scaffold alkaloid with remarkable selective antibacterial activity, is produced by marine fungus Curvularia sp. IFB-Z10. However, its deep pharmaceutical research and application are severely restricted by the low yield, which needs to be solved urgently. The purpose of this study was to improve curvulamine production via precursors co-addition strategy and further reveal the regulation mechanism. In this work, the optimal precursors co-addition conditions were firstly obtained, and curvulamine production achieved 166.74 mg/L with the supply of 250 mg/L alanine and 200 mg/L proline at 60 h, which was 4.08 times that of control. It was observed that under alanine and proline stimulation, fungus exhibited the morphology of a small-diameter compact pellet. Furthermore, the organic acid levels in central carbon metabolism (CCM) were declined with precursors supplement. Besides, precursors also induced the critical biosynthetic gene transcriptions. The above findings collectively promoted curvulamine synthesis. Finally, Curvularia sp. IFB-Z10 fermentation process was successfully established by feeding alanine and proline at 0.021 g/L/h and 0.017 g/L/h rate from 60 to 72 h, and curvulamine production reached 133.58 mg/L in a 5-L bioreactor. The information acquired would facilitate the enhancement of curvulamine yield in submerged fermentation and the research on synthesis regulation of other alkaloids.


Assuntos
Alcaloides/biossíntese , Ascomicetos/metabolismo , Aminoácidos/metabolismo , Ascomicetos/genética , Ascomicetos/crescimento & desenvolvimento , Reatores Biológicos , Metabolismo dos Carboidratos , Divisão Celular , Fermentação , Genes Fúngicos , Nitrogênio/metabolismo , Transcrição Genética
15.
Biosci Biotechnol Biochem ; 84(3): 433-444, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31738699

RESUMO

Ascomycota and basidiomycota fungi are prolific sources of biologically active natural products. Recent genomic data and bioinformatic analysis indicate that fungi possess a large number of biosynthetic gene clusters for bioactive natural products but more than 90% are silent. Heterologous expression in the filamentous fungi as hosts is one of the powerful tools to expression of the silent gene clusters. This review introduces recent studies on the total biosynthesis of representative family members via common platform intermediates, genome mining of novel di- and sesterterpenoids including detailed cyclization pathway, and development of expression host for basidiomycota genes with efficient genome editing method. In addition, this review will discuss the several strategies, for the generation of structural diversity, which are found through these studies.


Assuntos
Ascomicetos/metabolismo , Basidiomycota/metabolismo , Produtos Biológicos/metabolismo , Ascomicetos/genética , Basidiomycota/genética , Vias Biossintéticas/genética , Genes Fúngicos , Família Multigênica
16.
J Appl Microbiol ; 128(3): 747-762, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31710165

RESUMO

AIMS: Different endophytic fungi were isolated and screened for their digoxin-producing ability. Strain improvement and different culture conditions were studied for more effective production of digoxin. METHODS AND RESULTS: Among the isolated fungi, an isolate produced digoxin in a concentration of 2·07 mg l-1 . The digoxin-producing fungal isolate was identified as Epicoccum nigrum Link according to the morphological features and phylogenetic analyses. The potentiality of the fungal strain for production enhancement of digoxin was performed by gamma radiation mutagenesis. Gamma irradiation dose of 1000 Gy intensified the digoxin yield by five-fold. Using this dose, a stable mutant strain with improved digoxin productivity was isolated and the stability for digoxin production was followed up across four successive generations. In the effort to increase digoxin magnitude, selection of the proper cultivation medium, addition of some elicitors to the most proper medium and several physical fermentation conditions were tested. Fermentation process carried out in malt extract autolysate medium (pH 6·5) supplemented by methyl jasmonate and inoculated with 2 ml of 6-day-old culture and incubated at 25°C for 10 days stimulated the highest production of digoxin to attain 50·14 mg l-1 . Moreover, cytotoxicity of digoxin separated from the fungal culture was tested against five different cancer cell lines. Based on the MTT assay, digoxin inhibited the proliferation of the five different cancer cell lines and the recorded 50% inhibitory concentration ranged from 10·76 to 35·14 µg ml-1 . CONCLUSIONS: This is the first report on the production and enhancement of digoxin using fungal fermentation as a new and alternate source with high productivity. SIGNIFICANCE AND IMPACT OF THE STUDY: These findings offer new and alternate sources with excellent biotechnological potential for digoxin production by fungal fermentation. Moreover, digoxin proved to be a promising anticancer agent whose anticancer potential should be assessed in prospective cancer therapy.


Assuntos
Antineoplásicos/metabolismo , Ascomicetos/genética , Ascomicetos/metabolismo , Digoxina/metabolismo , Animais , Antineoplásicos/farmacologia , Ascomicetos/isolamento & purificação , Ascomicetos/efeitos da radiação , Células CHO , Linhagem Celular Tumoral , Cricetulus , Digoxina/farmacologia , Endófitos/genética , Endófitos/isolamento & purificação , Endófitos/metabolismo , Endófitos/efeitos da radiação , Fermentação , Raios gama , Humanos , Mutagênese , Filogenia
17.
J Agric Food Chem ; 68(1): 185-192, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31815467

RESUMO

Phytopathogenic fungi have been considered as being an enormous threat in the agricultural system. In our search of new antifungal natural products, nine new halogenated cyclopentenones, bicolorins A-I (1-3, and 5-10), along with three known cyclopentenones (4, 11, and 12) were isolated from the endophytic fungus Saccharicola bicolor of Bergenia purpurascens by the one strain-many compounds strategy. Their structures and absolute configurations were elucidated based on extensive spectroscopic analysis, X-ray crystallographic analysis, and time-dependent density functional theory-equivalent circulating density calculations. Compounds 1-12 showed antifungal activities against five phytopathogenic fungi (Uromyces viciae-fabae, Pythium dissimile, Gibberella zeae, Aspergillus niger, and Sclerotinia sclerotiorum). Especially, bicolorins B and D (2 and 5) exhibited strong antifungal activities against P. dissimile with the MIC values of 6.2 and 8.5 µg/mL, respectively, compared with the positive control cycloheximide (MIC of 8.6 µg/mL). Additionally, bicolorin D was proven to be potently antifungal against S. sclerotiorum in vitro and in vivo. This work provides an effective strategy for searching antifungal candidate agents.


Assuntos
Ascomicetos/química , Ciclopentanos/química , Ciclopentanos/farmacologia , Endófitos/química , Fungicidas Industriais/química , Fungicidas Industriais/farmacologia , Saxifragaceae/microbiologia , Ascomicetos/isolamento & purificação , Ascomicetos/metabolismo , Ciclopentanos/metabolismo , Endófitos/isolamento & purificação , Endófitos/metabolismo , Fungos/efeitos dos fármacos , Fungos/crescimento & desenvolvimento , Fungicidas Industriais/metabolismo , Halogenação , Estrutura Molecular , Doenças das Plantas/microbiologia
18.
Nat Prod Res ; 34(5): 646-650, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30388894

RESUMO

Alzheimer´s disease (AD) is the most common form of dementia involving Aß and tau protein. So far, AD cure remains elusive, but considering that AD progresses throughout tau pathology, which turns tau protein an appropriate target, besides tau is also included in other neurodegenerative disorders named as tauopathies. Here, we have isolated seventeen compounds belonging to six lichens species. Due to scarce of spectroscopic data of the compound 5,7-dihydroxy-6-methylphthalide, we explained their structural elucidation based on NMR data. In this study, we show that only tenuiorin from Umbilicaria antarctica inhibited 50% of tau 4R at 100 µM. Then, we shown that molecular interactions of tenuiorin with the steric zipper model of the hexapeptide 306VQIVYK311 were studied by docking calculations and the results suggested that tenuiorin forms both hydrogen bonds with lysine and glutamine side chains and forms several hydrophobic interactions with valine and lysine from 306VQIVYK311 motif.


Assuntos
Ascomicetos/química , Depsídeos/isolamento & purificação , Líquens/química , Resorcinóis/isolamento & purificação , Proteínas tau/antagonistas & inibidores , Doença de Alzheimer/tratamento farmacológico , Regiões Antárticas , Ascomicetos/metabolismo , Sítios de Ligação , Depsídeos/química , Humanos , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Ligação Proteica , Resorcinóis/química , Resorcinóis/metabolismo , Proteínas tau/metabolismo
19.
Genome ; 63(1): 37-52, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31580730

RESUMO

Lasiodiplodia theobromae (Pat.) Griffon & Maubl., a member of the family Botryosphaeriaceae, is becoming a significant threat to crops and woody plants in many parts of the world, including the major cacao growing areas. While attempting to isolate Ceratobasidium theobromae, a causal agent of vascular streak dieback (VSD), from symptomatic cacao stems, 74% of isolated fungi were Lasiodiplodia spp. Sequence-based identification of 52 putative isolates of L. theobromae indicated that diverse species of Lasiodiplodia were associated with cacao in the studied areas, and the isolates showed variation in aggressiveness when assayed using cacao leaf discs. The present study reports a 43.75 Mb de novo assembled genome of an isolate of L. theobromae from cacao. Ab initio gene prediction generated 13 061 protein-coding genes, of which 2862 are unique to L. theobromae, when compared with other closely related Botryosphaeriaceae. Transcriptome analysis revealed that 11 860 predicted genes were transcriptionally active and 1255 were more highly expressed in planta compared with cultured mycelia. The predicted genes differentially expressed during infection were mainly those involved in carbohydrate, pectin, and lignin catabolism, cytochrome P450, necrosis-inducing proteins, and putative effectors. These findings significantly expand our knowledge of the genome of L. theobromae and the genes involved in virulence and pathogenicity.


Assuntos
Ascomicetos/genética , Ascomicetos/patogenicidade , Cacau/microbiologia , Genoma Fúngico , Doenças das Plantas/microbiologia , Ascomicetos/isolamento & purificação , Ascomicetos/metabolismo , Proteínas Fúngicas/genética , Proteínas de Membrana/genética , RNA-Seq
20.
Chemosphere ; 238: 124700, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31524602

RESUMO

An eight-year field trial was conducted to investigate the effects of four different N fertilization treatments of urea (CO(NH2)2, the control), ammonium sulfate ((NH4)2SO4), ammonium chloride (NH4Cl), and ammonium hydrogen phosphate [(NH4)2HPO4]) on cadmium (Cd) phytotoxicity in rice and soil microbial communities in a Cd-contaminated paddy of southern China. The results demonstrate that the different N treatments exerted different effects: the application of (NH4)2HPO4 and (NH4)2SO4 significantly increased rice grain yield and decreased soil-extractable Cd content when compared with those of the control, while NH4Cl had a converse effect. Expression of genes related to Cd uptake (IRT and NRAPM genes) and transport (HMA genes) by roots may be responsible for Cd phytotoxicity in rice grown in the different N fertilization treatments. Our results further demonstrate that N fertilization had stronger effects on soil bacterial communities than fungal communities. The bacterial and fungal keystone species were identified by phylogenetic molecular ecological network (pMEN) analysis and mainly fell into the categories of Gammaproteobacteria, Acidobacteria and Actinobacteria for the bacterial species and Ascomycota for the fungal species; all of these keystone species were highly enriched in the (NH4)2HPO4 treatment. Soil pH and soil available-Cd content emerged as the major determinants of microbial network connectors. These results could provide effective fertilizing strategies for alleviating Cd phytotoxicity in rice and enhance the understanding of its underlying microbial mechanisms.


Assuntos
Ascomicetos/isolamento & purificação , Bactérias/isolamento & purificação , Cádmio/análise , Cádmio/toxicidade , Oryza/química , Poluentes do Solo/toxicidade , Acidobacteria/isolamento & purificação , Actinobacteria/isolamento & purificação , Cloreto de Amônio/química , Sulfato de Amônio/química , Ascomicetos/metabolismo , Bactérias/metabolismo , China , Grão Comestível/química , Poluição Ambiental/análise , Fertilizantes/análise , Gammaproteobacteria/isolamento & purificação , Microbiota , Oryza/microbiologia , Fosfatos/química , Filogenia , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Solo/química , Microbiologia do Solo , Poluentes do Solo/análise , Ureia/química
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