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1.
J Agric Food Chem ; 67(37): 10448-10457, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31453693

RESUMO

Carabrone is isolated from Carpesium macrocephalum Franch. et Sav, which has good fungicidal activity, especially for Gaeumannomyces graminis (Get). According to previous studies, we speculated that carabrone targets the mitochondrial enzyme complex III of Get. To elucidate the mode of action, we used carabrone to induce oxidative stress and apoptosis in Get. Incubation with carabrone reduced the burst of reactive oxygen species (ROS) and mitochondrial membrane potential, as well as phosphatidylserine release. Carabrone caused ROS accumulation in mycelia by inhibiting the activity of antioxidase enzymes, among which inhibition of glutathione reductase (GR) activity was most obvious. The catalytic center of GR consists of l-cysteine residues that react with the α-methylene-γ-butyrolactone active site of carabrone. Additionally, a positive TUNEL reaction led to diffusion of the DNA electrophoresis band and upregulation of Ggmet1 and Ggmet2. We propose that carabrone inhibits antioxidant enzymes and promotes ROS overproduction, which causes membrane hyperpermeability, release of apoptotic factors, activation of the mitochondria-mediated apoptosis pathway, and fungal cell apoptosis.


Assuntos
Apoptose/efeitos dos fármacos , Ascomicetos/efeitos dos fármacos , Fungicidas Industriais/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Ascomicetos/citologia , Ascomicetos/metabolismo , Asteraceae/química , Proteínas Fúngicas/metabolismo , Glutationa Redutase/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Espécies Reativas de Oxigênio/metabolismo
2.
Chem Biol Interact ; 311: 108798, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31433962

RESUMO

Natural products are a valuable source of anticancer agents, with many naturally derived compounds currently used in clinical and preclinical treatments. This study aims to investigate the antiproliferative activity and potential mechanism of action of the xanthoquinodin JBIR-99, isolated from fungi Parengyodontium album MEXU 30,054 and identified by single-crystal X-ray crystallography. Cytotoxicity of xanthoquinodin was evaluated in a panel of human cancer cells lines and CCD-112-CoN normal colon cells, using the sulforhodamine B assay. PC-3 prostate cancer cells were used in biochemical assays including cell cycle, mitochondrial transmembrane potential (MTP), reactive oxygen species (ROS) and caspase activity. Expression levels of apoptosis-pathway-related proteins were analyzed by Western blot. The in vivo toxicity of xanthoquinodin was determined using a zebrafish model. Xanthoquinodin showed cytotoxicity in all cancer cell lines but demonstrated relative selective potency against PC-3 cells with an IC50 1.7 µM. In CCD-112-CoN cells, xanthoquinodin was non-cytotoxic at 100 µM. In PC-3 cells, the compound induced loss of MTP, production of ROS, and cell cycle arrest in S phase. The expression and activity of caspase-3 was increased, which correlates with the upregulation of Cyt c, Bax, nuclear factor kappa-B (NF-κB) (p65) and IKKß, and downregulation of poly ADP ribose polymerase (PARP-1) and Bcl-2. Lastly, xanthoquinodin did not cause any visible developmental toxicity in zebrafish at 50 µM. These results demonstrate xanthoquinodin induces apoptosis in PC-3 prostate cancer cells by activation of both intrinsic and extrinsic apoptotic pathways. In addition, the non-toxic effect in vivo indicates that xanthoquinodin could be a useful lead in the development of a novel, anti-cancer agent that is selective for prostate cancer.


Assuntos
Apoptose/efeitos dos fármacos , Ascomicetos/química , Cromonas/farmacologia , Ascomicetos/metabolismo , Linhagem Celular Tumoral , Cromonas/química , Cristalografia por Raios X , Citocromos c/metabolismo , Humanos , Quinase I-kappa B/metabolismo , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Conformação Molecular , Poli(ADP-Ribose) Polimerase-1/metabolismo , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteínas Repressoras/metabolismo , Pontos de Checagem da Fase S do Ciclo Celular/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
3.
World J Microbiol Biotechnol ; 35(7): 105, 2019 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-31267317

RESUMO

Pseudocercospora fijiensis causes black Sigatoka disease, the most important threat to banana. The cell wall is crucial for fungal biological processes, including pathogenesis. Here, we performed cell wall proteomics analyses of two P. fijiensis strains, the highly virulent Oz2b, and the less virulent C1233 strains. Strains were starved from nitrogen to mimic the host environment. Interestingly, in vitro cultures of the C1233 strain grew faster than Oz2b in PDB medium, suggesting that C1233 survives outside the host better than the highly virulent Oz2b strain. Both strains were submitted to nitrogen starvation and the cell wall proteins were isolated and subjected to nano-HPLC-MS/MS. A total of 2686 proteins were obtained from which only 240 had a known function and thus, bioinformatics analyses were performed on this group. We found that 90 cell wall proteins were shared by both strains, 21 were unique for Oz2b and 39 for C1233. Shared proteins comprised 24 pathogenicity factors, including Avr4 and Ecp6, two effectors from P. fijiensis, while the unique proteins comprised 16 virulence factors in C1233 and 11 in Oz2b. The P. fijiensis cell wall proteome comprised canonical proteins, but thirty percent were atypical, a feature which in other phytopathogens has been interpreted as contamination. However, a comparison with the identities of atypical proteins in other reports suggests that the P. fijiensis proteins we detected were not contaminants. This is the first proteomics analysis of the P. fijiensis cell wall and our results expands the understanding of the fundamental biology of fungal phytopathogens and will help to decipher the molecular mechanisms of pathogenesis and virulence in P. fijiensis.


Assuntos
Ascomicetos/genética , Ascomicetos/metabolismo , Parede Celular/genética , Parede Celular/metabolismo , Proteoma , Fatores de Virulência/genética , Fatores de Virulência/metabolismo , Ascomicetos/isolamento & purificação , Ascomicetos/patogenicidade , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Genes Fúngicos/genética , Genoma Fúngico , Musa/microbiologia , Doenças das Plantas/microbiologia , Folhas de Planta/microbiologia , Espectrometria de Massas em Tandem , Virulência
4.
Ecotoxicol Environ Saf ; 181: 481-490, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31228824

RESUMO

Peroxidases and catalases are well-known antioxidant enzymes produced in almost all living organisms for the elimination of reactive oxygen species (ROS) and thus they prevent the occurrence of oxidative stress. In our study we focused on two soil fungi of the family Chaetomiaceae (mesophilic Chaetomium cochliodes and its thermophilic counterpart C. thermophilum var. dissitum) in order to explore the presence of peroxidase and catalase genes, formation of their native transcripts and protective effect of corresponding translation products in a case study. Predicted genes of our interest were confirmed by genomic PCR and their inducible transcripts by RT-PCR. We were able to quantify the expression levels of newly discovered fungal heme peroxidases and catalases with the reverse-transcription quantitative real-time PCR method. We compared obtained quantitative levels of mRNA production with the level of corresponding extracellular protein occurrence as detected with monitoring their specific peroxidase and catalase activities directly in the cultivation media at optimal growth temperatures. The presence of secretory Catalase 2 from C. thermophilum var. dissitum was detected and identified with mass spectrometry approach directly in the growth medium. This unique catalase is phylogenetically closely related with a previously described catalase-phenol oxidase thus representing an effective and versatile antioxidant in the environment of the fungal mycelia also involved in the catabolism of recalcitrant phenolic substances.


Assuntos
Ascomicetos/metabolismo , Catalase/metabolismo , Espaço Extracelular/enzimologia , Estresse Oxidativo , Peroxidases/metabolismo , Antioxidantes/metabolismo , Ascomicetos/classificação , Ascomicetos/enzimologia , Ascomicetos/genética , Catalase/genética , Meios de Cultura/metabolismo , Espaço Extracelular/metabolismo , Oxirredução , Peroxidases/genética , Filogenia , Temperatura Ambiente
5.
Ecotoxicol Environ Saf ; 181: 187-193, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31195227

RESUMO

Microbial polysaccharides, due to their unique physiochemical properties, have found application in the food industry, cosmetics, pharmacy and medicine. In the environment, microbes can use polysaccharides to alleviate the adverse effects of heavy metals in their close proximity. This adaptive property shows interesting potential for bioremediation. Herein, the effects of the exopolysaccharides (EPS) levan, produced by the bacterium Bacillus licheniformis NS032 and pullulan, produced by the fungus Aureobasidium pullulans CH-1 in the presence of copper (Cu2+) have been investigated for the first time on antioxidant enzyme activity, respiration and Cu2+ bioaccumulation of Daphnia magna as well as the bioluminescence of Vibrio fischeri. Both EPS decreased toxicity of Cu2+ in the acute test with D. magna. The activity of catalase (CAT) was significantly diminished after acute exposure to Cu2+ in comparison to treatments with Cu2+ and EPS, while in the prolonged acute exposure the CAT activity did not show statistically significant (P ≤ 0.05) differences between treatments with and without the EPS. According to ICP-MS results, during prolonged acute exposure of neonates, the bioaccumulation of Cu2+ in treatments without the EPS was 52.03 µg/g of biomass (wet), while in treatments with EPS, the bioaccumulation was lower by one order of magnitude. The respiration of neonates during acute exposure to Cu2+ with or without the EPS was monitored using the MicroOxymax respirometer, and the results show the EPS can positively effect the respiration. In the case of bacterial bioluminescence, the toxicity of Cu2+ decreased in treatments with EPS (30 min EC10) from 3.54 mg/L to 140.61 mg/L (levan) and 45.00 mg/L (pullulan). This study demonstrates protective effect of EPS against Cu2+ toxicity on D. magna and V. fischeri, and opens the door for further investigation of potential application of levan and pullulan in bioremediation of heavy metals and mitigation of their adverse effects in the aquatic environment.


Assuntos
Cobre/toxicidade , Frutanos/farmacologia , Glucanos/farmacologia , Poluentes Químicos da Água/toxicidade , Aliivibrio fischeri/química , Aliivibrio fischeri/efeitos dos fármacos , Animais , Ascomicetos/metabolismo , Bacillus licheniformis/metabolismo , Catalase/metabolismo , Cobre/farmacocinética , Daphnia/efeitos dos fármacos , Daphnia/enzimologia , Daphnia/crescimento & desenvolvimento , Daphnia/metabolismo , Luminescência , Substâncias Protetoras/farmacologia , Poluentes Químicos da Água/farmacocinética
6.
Plant Dis ; 103(8): 2076-2082, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31194616

RESUMO

Stem-end rot caused by Botryodiplodia theobromae is a destructive disease of mango. B. theobromae field isolates resistant to carbendazim (MBC) were collected in Hainan Province, China. In this study, the characteristics of these field isolates with resistance to MBC were investigated. The resistance of B. theobromae isolates to MBC was stably inherited. Both the MBC-resistant and MBC-sensitive isolates had similar mycelial growth rates, pathogenicity, sensitivity to high glucose, glycerol content, and peroxidase activity. Compared with MBC-sensitive isolates, MBC-resistant isolates were more sensitive to low temperature and had a significant decrease in sensitivity to high NaCl and a significant increase in catalase (CAT) and glutathione S-transferase (GST) activities. After MBC treatment, the cell membrane permeability of the sensitive isolates was markedly increased compared with that of the resistant isolates. Analysis of the ß-tubulin gene sequence revealed point mutations resulting in substitutions at codon 198 from glutamic acid (GAG) to alanine (GCG) in moderately resistant isolates, and at codon 200 from phenylalanine (TTC) to tyrosine (TAC) in highly resistant isolates. These ß-tubulin gene mutations were consistently associated with MBC resistance. Overall, we infer that the altered cell membrane permeability and the increase in CAT and GST activities of the resistant isolates are linked to MBC resistance.


Assuntos
Ascomicetos , Benzimidazóis , Carbamatos , Farmacorresistência Fúngica , Fungicidas Industriais , Ascomicetos/efeitos dos fármacos , Ascomicetos/enzimologia , Ascomicetos/genética , Ascomicetos/metabolismo , Benzimidazóis/farmacologia , Carbamatos/farmacologia , China , Farmacorresistência Fúngica/genética , Fungicidas Industriais/farmacologia , Genes Fúngicos/genética
7.
Carbohydr Polym ; 219: 368-377, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31151536

RESUMO

A water-soluble polysaccharide was isolated from Tornabea scutellifera and fractionated using a DAEA Sepharose FF column to evaluate its capacity to stimulate natural killer (NK) cells and macrophages. Neutral sugars (71.8-93.5%) constituted the major part of crude polysaccharides and fractions (TSF1 and TSF2) with relatively lower levels of proteins (0.4-20.3%) and uronic acids (0.8-4.9%). The weight average molecular weights (Mw) of 152.7-537.3 × 103 g/mol were measured for isolated polysaccharides. The polysaccharides were composed of glucose (14.4-44.0%), galactose (23.2-43.2%), mannose (28.5-34.2%) and rhamnose (2.6-13.9%) units connected through (1→2)-Galp, (1→2,6)-Galp, (1→4)-Glcp, (1→6)-Glcp, (1→3)-Rhap, (1→2)-Rhap and (1→4)-Manp residues. TSF2 polysaccharide effectively induced RAW264.7 murine macrophages to release nitric oxide, TNF-α, IL-1ß and IL-6, and activated NK cells to produce TNF-α, INF-γ, granzyme-B, perforin, NKG2D and FasL through NF-κB and MAPKs signaling pathways. Overall results suggested that polysaccharides from T. scutellifera could be potent immunostimulatory compounds inducing both macrophages and NK cells.


Assuntos
Ascomicetos/metabolismo , Citocinas/metabolismo , Fatores Imunológicos/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Óxido Nítrico/metabolismo , Polissacarídeos/farmacologia , Animais , Galactose/química , Glucose/química , Irã (Geográfico) , Células Matadoras Naturais , Manose/química , Camundongos , Polissacarídeos/química , Células RAW 264.7 , Ramnose/química , Ácidos Urônicos/metabolismo
8.
J Sci Food Agric ; 99(13): 5899-5909, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31225657

RESUMO

BACKGROUND: Most allelochemicals are secondary products released from root excretions or plant residues that accumulate in continuous cropping systems and cause severe decline in peanut yield. Resveratrol is a plant-derived stilbene that is released from peanut residues and accumulates in the soil; however, its allelopathic effects on peanut production are overlooked. Effective management solutions need to be developed to relieve allelopathy caused by soil resveratrol. Here, the biodegradation of resveratrol by the fungal endophyte Phomopsis liquidambari was investigated in a mineral salt medium and a soil trial. Resveratrol and its metabolites (produced by degradation by P. liquidambari) were detected by high-performance liquid chromatography-mass spectrometry (HPLC-MS). RESULTS: Resveratrol released from peanut residues reached a maximum concentration of 0.18 µg g-1 soil in litterbag experiments. Exogenous resveratrol inhibited peanut growth, nodule formation, and soil dehydrogenase activity, and reduced the soil microbial biomass carbon content and bacterial abundance, indicating an allelopathic role in peanut growth. More than 97% of the resveratrol was degraded within 72 and 168 h by P. liquidambari in pure culture and soil conditions, respectively. Resveratrol was first cleaved to 3,5-dihydroxybenzaldehyde and 4-hydroxybenzaldehyde, which were subsequently oxidized into 3,5-dihydroxybenzoic acid and 4-hydroxybenzoic acid, respectively. Fungal resveratrol cleavage oxygenase and the related gene expression were enhanced when P. liquidambari was induced by the resveratrol during the incubation. CONCLUSION: Our results indicate that the practical application of the fungal endophyte P. liquidambari has strong potential for biodegrading soil resveratrol, which can cause allelopathy in peanut continuous cropping systems. © 2019 Society of Chemical Industry.


Assuntos
Arachis/química , Ascomicetos/metabolismo , Endófitos/metabolismo , Feromônios/metabolismo , Resveratrol/metabolismo , Arachis/metabolismo , Arachis/microbiologia , Bactérias/classificação , Bactérias/efeitos dos fármacos , Bactérias/genética , Bactérias/isolamento & purificação , Biodegradação Ambiental , Feromônios/análise , Feromônios/farmacologia , Resveratrol/análise , Resveratrol/farmacologia , Solo/química , Microbiologia do Solo
9.
Molecules ; 24(9)2019 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-31052486

RESUMO

Morels famous for their taste and nutrition are in short supply all over the world although they were considered as one of the most highly prized edible and medicinal mushrooms. Because of the limitation of resource and cultivation technology, fermentation of edible mushroom was gradually applied to nutrient, bioactivity and breeder seed preparation. At present, there are more reports on sugar and amino acid but less on other components. Morchella sp. YDJ-ZY-1 was isolated from the wild fruiting body by the spores releasing method in Zunyi Guizhou province in Southwest China and identified based on phenotype and genotype characteristics. Chemical compositions of YDJ-ZY-1 were investigated from liquid fermentation that will lay the foundation for further development and utilization. Four pyranoids (1-4) and 2-(1-oxo-2-hydroxyethyl) furan (5), linoleic acid (6), Morelin (2-hydroxy-cinnamic acid methyl ester, (7) and 1-O-ß-d-ribofuranose-Morelin (8) were obtained from EtOAc extraction and elucidated by spectral data. Product 4 and 8 were new compounds and 7 was isolated from nature for the first time. Antiradical activity was evaluated by free radical scavenging effect on DPPH (1,1-Diphenyl-2-picrylhydrazyl radical 2,2-Diphenyl-1-(2,4,6-trinitrophenyl)hydrazyl). Compound 5 exhibited strong antiradical activity while compounds 1 and 2 exhibited moderate activity. Thus, incubation of Morchella sp YDJ-ZY-1 separated from the wild fruit body afforded eight compounds. Secondary metabolites with new structures were mined from fermentation of Morchella sp. and antiradical activity was evaluated.


Assuntos
Ascomicetos/metabolismo , Produtos Biológicos/isolamento & purificação , Produtos Biológicos/farmacologia , Fermentação , Depuradores de Radicais Livres/isolamento & purificação , Depuradores de Radicais Livres/farmacologia , Metabolismo Secundário , Agaricales , Ascomicetos/classificação , Ascomicetos/ultraestrutura , Produtos Biológicos/química , China , Depuradores de Radicais Livres/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular
10.
Fungal Biol ; 123(5): 397-407, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31053329

RESUMO

Fungal secondary metabolites have important functions for the fungi that produce them, such as roles in virulence and competition. The hemibiotrophic pine needle pathogen Dothistroma septosporum has one of the lowest complements of secondary metabolite (SM) backbone genes of plant pathogenic fungi, indicating that this fungus produces a limited range of SMs. Amongst these SMs is dothistromin, a well-characterised polyketide toxin and virulence factor that is required for expansion of disease lesions in Dothistroma needle blight disease. Dothistromin genes are dispersed across six loci on one chromosome, rather than being clustered as for most SM genes. We explored other D. septosporum SM genes to determine if they are associated with gene clusters, and to predict what their likely products and functions might be. Of nine functional SM backbone genes in the D. septosporum genome, only four were expressed under a range of in planta and in culture conditions, one of which was the dothistromin PKS backbone gene. Of the other three expressed genes, gene knockout studies suggested that DsPks1 and DsPks2 are not required for virulence and attempts to determine a functional squalestatin-like SM product for DsPks2 were not successful. However preliminary evidence suggested that DsNps3, the only SM backbone gene to be most highly expressed in the early stage of disease, appears to be a virulence factor. Thus, despite the small number of SM backbone genes in D. septosporum, most of them appear to be poorly expressed or dispensable for virulence in planta. This work contributes to a growing body of evidence that many fungal secondary metabolite gene clusters might be non-functional and may be evolutionary relics.


Assuntos
Ascomicetos/genética , Ascomicetos/metabolismo , Redes e Vias Metabólicas/genética , Metabolismo Secundário , Antraquinonas/metabolismo , Ascomicetos/crescimento & desenvolvimento , Ascomicetos/isolamento & purificação , Perfilação da Expressão Gênica , Família Multigênica , Pinus/microbiologia , Doenças das Plantas/microbiologia , Folhas de Planta/microbiologia
11.
Carbohydr Polym ; 217: 46-57, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31079684

RESUMO

Pullulan is a microbial exopolysaccharide produced from Aureobasidium pullulans by submerged fermentation of a medium supplemented with carbon, nitrogen and other essential nutrients. These nutrients are expensive which increase the cost of pullulan production. The requirement of alternative cost-effective substrates for pullulan production is a prerequisite. Agro-based industries generate a large volume of solid/liquid waste and its accumulation generates a severe environmental impact. These wastes are composed of carbohydrates, proteins and other constituents, and can be used as substrates for the development of low-cost processes for the production of various microbial products. This could be a good environmental friendly waste management system. Pullulan production from agro-industrial wastes can be carried out by both submerged and solid-state fermentation by A. pullulans. Owing to its unique properties, pullulan has wide applications in many food-based industries. This review highlights pullulan production from agro-industrial wastes and potential applications of pullulan in various food industries.


Assuntos
Indústria Alimentícia/métodos , Glucanos/biossíntese , Resíduos Industriais , Agricultura/métodos , Ascomicetos/metabolismo , Fermentação , Resíduos Sólidos
12.
Lett Appl Microbiol ; 69(2): 88-95, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31102470

RESUMO

Natural enzyme inhibitors have been widely described in literature because of its pharmacological and cosmetic applications. Fungi found in caves represent a promising source of bioactive substances that are still little explored scientifically. Thus, the present work evaluated the presence of enzymatic modulators in a filtrate obtained from the cultivation of the cave fungus Lecanicillium aphanocladii (Family: Cordycipitaceae). Snake venoms from Bothrops alternatus and Bothrops atrox were used as an enzymatic source for the induction of the phospholipase, proteolytic, thrombolytic, cytotoxic and coagulant activities. Compounds present in the fungal filtrate inhibited 50, 23·8, 26·6, 50·9 and 52·5% of the proteolytic, phospholipase, haemolytic, thrombolytic and coagulant activities respectively. The filtrate was not cytotoxic on erythrocytes, but induced partial dissolution of thrombi. Fungal enzyme inhibitors that have low or no toxicity and can be obtained on a large scale and at low cost are relevant in the medical-scientific context. Therefore, the inhibition of phospholipases A2 and proteases observed in the present work highlights the potential of fungal metabolites for the development of drugs that can be used in the treatment of haemostasis and inflammation-related disorders. SIGNIFICANCE AND IMPACT OF THE STUDY: In this study, secondary metabolites synthesized by Lecanicillium aphanocladii, a fungus isolated from caves, demonstrated modulating action on proteases and phospholipases A2 present in snake venoms of the Bothrops genus, widely used as tools for the study of pathophysiology processes related to haemostasis and inflammation. The results suggest the possibility of future applications for these metabolites in the development of pharmaceuticals of medical-scientific interest.


Assuntos
Ascomicetos/química , Bothrops/metabolismo , Venenos de Crotalídeos/enzimologia , Peptídeo Hidrolases/metabolismo , Inibidores de Fosfolipase A2/farmacologia , Fosfolipases A2/metabolismo , Inibidores de Proteases/farmacologia , Animais , Ascomicetos/metabolismo , Coagulação Sanguínea/efeitos dos fármacos , Eritrócitos/efeitos dos fármacos , Hemostasia/efeitos dos fármacos , Humanos , Inflamação/tratamento farmacológico , Proteólise/efeitos dos fármacos
13.
World J Microbiol Biotechnol ; 35(5): 69, 2019 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-31011888

RESUMO

The filamentous Bipolaris and Curvularia genera consist of species known to cause severe diseases in plants and animals amounting to an estimated annual loss of USD $10 billion worldwide. Despite the harmful effect of Bipolaris and Curvularia species, scarce attention is paid on beneficial areas where the fungi are used in industrial processes to generate biotechnological products. Catalytic potential of Bipolaris and Curvularia species in the production of biodiesel, bioflucculant, biosorbent, and mycoherbicide are promising for the bioeconomy. It is herein demonstrated that knowledge-based application of some endophytic Bipolaris and Curvularia species are indispensable vectors of sustainable economic development. In the twenty-first century, India, China, and the USA have taken progress in the biotechnological application of these fungi to generate wealth. As such, some Bipolaris and Curvularia species significantly impact on global crop improvement, act as catalyst in batch-reactors for biosynthesis of industrial enzymes and medicines, bioengineer of green-nanoparticle, agent of biofertilizer, bioremediation and bio-hydrometallurgy. For the first time, this study discusses the current advances in biotechnological application of Bipolaris and Curvularia species and provide new insights into the prospects of optimizing their bioengineering potential for developing bioeconomy.


Assuntos
Ascomicetos , Bioengenharia , Biotecnologia , Endófitos , Ascomicetos/classificação , Ascomicetos/enzimologia , Ascomicetos/metabolismo , Biodegradação Ambiental , Biocombustíveis , Agentes de Controle Biológico , Biotransformação , Endófitos/classificação , Endófitos/enzimologia , Endófitos/metabolismo , Fertilizantes , Floculação , Micovírus , Herbicidas , Metalurgia , Nanopartículas , Solo/química , Simbiose , Termotolerância , Urânio
14.
Plant Physiol Biochem ; 139: 459-469, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30999133

RESUMO

Salinity stress can severely affect the growth and production of the crop plants. Cheap and reliable actions are needed to enable the crop plants to grow normal under saline conditions. Modification at the molecular level to produce resistant cultivars is one of the promising, yet highly expensive techniques, whereas application of endophytes on the other hand are very cheap. In this regard, the role of Cochliobolus sp. in alleviating NaCl-induced stress in okra has been investigated. The growth and biomass yield, relative water content, chlorophyll content and IAA were decreased, whereas malondialdehyde (MDA) and proline content were increased in okra plants treated with 100 mM NaCl. On the contrary, okra plants inoculated with C. lunatus had higher shoot length, root length, plant dry weight, chlorophyll, carotenoids, xanthophyll, phenolicss, flavonoids, IAA, total soluble sugar and relative water content, while lower MDA. LC-MS/MS analysis of the Cochliobolus sp. extract revealed the presence of pinocembrin, chlorogenic acids, wogonin, calycosin and diadzein as a salinity stress reliever. From the results, it can be concluded that colonization of Cochliobolus sp. improves the NaCl tolerance by ameliorating the physicochemical attributes of the host plants.


Assuntos
Abelmoschus/efeitos dos fármacos , Abelmoschus/microbiologia , Ascomicetos/metabolismo , Ascomicetos/fisiologia , Cloreto de Sódio/farmacologia , Abelmoschus/metabolismo , Malondialdeído/metabolismo , Prolina/metabolismo , Salinidade , Espectrometria de Massas em Tandem
15.
Pestic Biochem Physiol ; 156: 123-128, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31027571

RESUMO

Sclerotinia homoeocarpa causes dollar spot disease on turfgrass and is a serious problem on many species worldwide. Fludioxonil, a phenylpyrrole fungicide, is not currently registered for dollar spot control in China. In this study, the baseline sensitivity to fludioxonil was established using an in vitro assay for 105 isolates of S. homoeocarpa collected from 10 locations in different regions of China. Results indicate that the frequency distribution of effective concentration for 50% inhibition of mycelial growth (EC50) values of the S. homoeocarpa isolates was unimodal (W = 0.9847, P = .2730). The mean EC50 value was 0.0020 ±â€¯0.0006 µg/ml with a range from 0.0003 to 0.0035 µg/ml. A total of 7 fludioxonil-resistant mutants were obtained in laboratory, the mutants were stable in fludioxonil sensitivity after the 10th transfer, with resistance factor (RF) ranging from 4.320 to >13,901.4. The mutants showed a positive cross-resistance between fludioxonil and the dicarboximide fungicide iprodione, but not propiconazole, fluazinam, and thiophanate-methyl. When mycelial growth rate, pathogenicity and osmotic sensitivity were assessed, the mutants decreased in the fitness compared with their parental isolates. Sequence alignment of the histidine kinase gene Shos1 revealed a 13-bp fragment deletion only in one mutant, no mutations were observed on Shos1 in the rest resistant mutants.


Assuntos
Ascomicetos/efeitos dos fármacos , Ascomicetos/metabolismo , Dioxóis/farmacologia , Fungicidas Industriais/farmacologia , Pirróis/farmacologia , Aminoimidazol Carboxamida/análogos & derivados , Aminoimidazol Carboxamida/farmacologia , Aminopiridinas/farmacologia , Ascomicetos/genética , China , Farmacorresistência Fúngica/genética , Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Regulação Fúngica da Expressão Gênica/genética , Hidantoínas/farmacologia , Mutação/genética , Tiofanato/farmacologia , Triazóis/farmacologia
16.
Biomolecules ; 9(4)2019 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-30934922

RESUMO

Greensporone A is a fungal secondary metabolite that has exhibited potential in vitro for anti-proliferative activity in vitro. We studied the anticancer activity of greensporone A in a panel of leukemic cell lines. Greensporone A-mediated inhibition of proliferation is found to be associated with the induction of apoptotic cell death. Greensporone A treatment of leukemic cells causes inactivation of constitutively activated AKT and its downstream targets, including members GSK3 and FOXO1, and causes downregulation of antiapoptotic genes such as Inhibitor of Apoptosis (IAPs) and Bcl-2. Furthermore, Bax, a proapoptotic member of the Bcl-2 family, was found to be upregulated in leukemic cell lines treated with greensporone A. Interestingly, gene silencing of AKT using AKT specific siRNA suppressed the expression of Bcl-2 with enhanced expression of Bax. Greensporone A-mediated increase in Bax/Bcl-2 ratio causes permeabilization of the mitochondrial membrane leading to the accumulation of cytochrome c in the cytoplasm. Greensporone A-induced cytochrome c accumulation causes the activation of caspase cascade and cleavage of its effector, poly(ADP-ribose) polymerase (PARP), leading to apoptosis. Greensporone A-mediated apoptosis in leukemic cells occurs through the generation of reactive oxygen species (ROS) due to depletion of glutathione (GSH) levels. Finally, greensporone A potentiated the anticancer activity of imatinib in leukemic cells. In summary, our study showed that greensporone A suppressed the growth of leukemic cells via induction of apoptotic cell death. The apoptotic cell death occurs by inhibition of AKT signaling and activation of the intrinsic apoptotic/caspase pathways. These results raise the possibility that greensporone A could be developed as a therapeutic agent for the treatment of leukemia and other hematological malignancies.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Ascomicetos/química , Macrolídeos/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Ascomicetos/metabolismo , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Macrolídeos/química , Macrolídeos/isolamento & purificação , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Estrutura Molecular , Proteínas Proto-Oncogênicas c-akt , Espécies Reativas de Oxigênio/análise , Metabolismo Secundário , Relação Estrutura-Atividade , Células Tumorais Cultivadas
17.
Appl Microbiol Biotechnol ; 103(12): 4741-4752, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31020382

RESUMO

Liamocins are biosurfactants produced by the fungus Aureobasidium pullulans. A. pullulans belongs to the black yeasts and is known for its ability to produce pullulan and melanin. However, the production of liamocins has not been investigated intensively. Initially, HPLC methods for the quantification of liamocin and the identification of liamocin congeners were established. Eleven congeners could be detected, differing in the polyol head groups arabitol or mannitol. In addition, headless molecules, so-called exophilins, were also identified. The HPLC method reported here allows quick and reliable quantification of all identified congeners, an often-overlooked prerequisite for the investigation of valuable product formation. Liamocin synthesis was optimized during cultivation in lab-scale fermenters. While the pH can be kept constant, the best strategy for liamocin synthesis consists of a growth phase at neutral pH and a subsequent production phase induced by a manual pH shift to pH 3.5. Finally, combining increased nitrogen availability with a pulsed fed-batch fermentation, cell growth, and liamocin titers could be enhanced. Here, the maximal titers of above 10 g/L that were reached are the highest reported to date for liamocin synthesis using A. pullulans in lab-scale fermenters.


Assuntos
Ascomicetos/metabolismo , Meios de Cultura/química , Fermentação , Manitol/análogos & derivados , Óleos/metabolismo , Tensoativos/metabolismo , Técnicas de Cultura Celular por Lotes , Reatores Biológicos , Concentração de Íons de Hidrogênio , Microbiologia Industrial , Manitol/metabolismo , Nitrogênio/metabolismo , Álcoois Açúcares/metabolismo
18.
Fungal Biol ; 123(4): 318-329, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30928040

RESUMO

In lichen symbiosis, polyol transfer from green algae is important for acquiring the fungal carbon source. However, the existence of polyol transporter genes and their correlation with lichenization remain unclear. Here, we report candidate polyol transporter genes selected from the genome of the lichen-forming fungus (LFF) Ramalina conduplicans. A phylogenetic analysis using characterized polyol and monosaccharide transporter proteins and hypothetical polyol transporter proteins of R. conduplicans and various ascomycetous fungi suggested that the characterized yeast' polyol transporters form multiple clades with the polyol transporter-like proteins selected from the diverse ascomycetous taxa. Thus, polyol transporter genes are widely conserved among Ascomycota, regardless of lichen-forming status. In addition, the phylogenetic clusters suggested that LFFs belonging to Lecanoromycetes have duplicated proteins in each cluster. Consequently, the number of sequences similar to characterized yeast' polyol transporters were evaluated using the genomes of 472 species or strains of Ascomycota. Among these, LFFs belonging to Lecanoromycetes had greater numbers of deduced polyol transporter proteins. Thus, various polyol transporters are conserved in Ascomycota and polyol transporter genes appear to have expanded during the evolution of Lecanoromycetes.


Assuntos
Ascomicetos/enzimologia , Ascomicetos/metabolismo , Líquens/microbiologia , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Polímeros/metabolismo , Ascomicetos/genética , Sequência Conservada , Filogenia , Homologia de Sequência
19.
Prep Biochem Biotechnol ; 49(6): 557-566, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30957655

RESUMO

Pullulan is an extracellular water-soluble polysaccharide with wide applications. In this study, we screened strains that could selectively produce high molecular weight pullulan for application in industrial pullulan production. A new fungus strain A4 was isolated from soil and identified as Aureobasidium melanogenum based on colony characteristics, morphology, and internally transcribed spacer analysis. Thin-layer chromatography, Fourier-transform infrared spectroscopy, and nuclear magnetic resonance analysis suggested that the dominant exopolysaccharide produced by this strain, which presented a molecular weight of 1.384 × 106 Dalton in in-gel permeation chromatography, was pullulan. The culture conditions for A. melanogenum A4 were optimized at 30 °C and 180 rpm: carbon source, 50 g/L maltose; initial pH 7; and 8 g/L Tween 80. Subsequently, batch fermentation was performed under the optimized conditions in a 5-L stirred-tank fermentor with a working volume of 3 L. The fermentation broth contained 303 g/L maltose, which produced 122.34 g/L pullulan with an average productivity of 1.0195 g/L/h and 82.32 g/L dry biomass within 120 h. The conversion efficiency of maltose to pullulan (Y%) and specific production rate (g/h/g dry cells) (Qs) reached 40.3% and 0.0251 g/L/g dry cells, respectively. The results showed strain A4 could be a good candidate for industrial production.


Assuntos
Ascomicetos/metabolismo , Glucanos/biossíntese , Biomassa , Cromatografia em Camada Delgada , Meios de Cultura , Fermentação/efeitos dos fármacos , Glucanos/química , Glucanos/isolamento & purificação , Concentração de Íons de Hidrogênio , Espectroscopia de Ressonância Magnética , Peso Molecular , Polissorbatos/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier , Açúcares/metabolismo
20.
PLoS Genet ; 15(4): e1008093, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-31009462

RESUMO

Chromosome and genome stability are important for normal cell function as instability often correlates with disease and dysfunction of DNA repair mechanisms. Many organisms maintain supernumerary or accessory chromosomes that deviate from standard chromosomes. The pathogenic fungus Zymoseptoria tritici has as many as eight accessory chromosomes, which are highly unstable during meiosis and mitosis, transcriptionally repressed, show enrichment of repetitive elements, and enrichment with heterochromatic histone methylation marks, e.g., trimethylation of H3 lysine 9 or lysine 27 (H3K9me3, H3K27me3). To elucidate the role of heterochromatin on genome stability in Z. tritici, we deleted the genes encoding the methyltransferases responsible for H3K9me3 and H3K27me3, kmt1 and kmt6, respectively, and generated a double mutant. We combined experimental evolution and genomic analyses to determine the impact of these deletions on chromosome and genome stability, both in vitro and in planta. We used whole genome sequencing, ChIP-seq, and RNA-seq to compare changes in genome and chromatin structure, and differences in gene expression between mutant and wildtype strains. Analyses of genome and ChIP-seq data in H3K9me3-deficient strains revealed dramatic chromatin reorganization, where H3K27me3 is mostly relocalized into regions that are enriched with H3K9me3 in wild type. Many genome rearrangements and formation of new chromosomes were found in the absence of H3K9me3, accompanied by activation of transposable elements. In stark contrast, loss of H3K27me3 actually increased the stability of accessory chromosomes under normal growth conditions in vitro, even without large scale changes in gene activity. We conclude that H3K9me3 is important for the maintenance of genome stability because it disallows H3K27me3 in regions considered constitutive heterochromatin. In this system, H3K27me3 reduces the overall stability of accessory chromosomes, generating a "metastable" state for these quasi-essential regions of the genome.


Assuntos
Instabilidade Genômica , Histonas/metabolismo , Lisina/metabolismo , Ascomicetos/genética , Ascomicetos/metabolismo , Cromossomos Fúngicos , Deleção de Genes , Heterocromatina/genética , Heterocromatina/metabolismo , Histona-Lisina N-Metiltransferase/genética , Histonas/química , Metilação , Sequências Repetitivas de Ácido Nucleico , Ativação Transcricional
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