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1.
Ann Agric Environ Med ; 28(3): 414-418, 2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34558263

RESUMO

INTRODUCTION: Fusaria are microscopic filamentous fungi which are spread in soil, in various organic substrates, and include more than 80 phytopathogenic species which are predominantly hosted by cereals, fruits and vegetables. Many of these species, under certain conditions, are capable of synthesizing secondary metabolites, mycotoxins. At present, various substances are used for their elimination and one of the solutions appears to be essential oils. In the presented study, the antifungal activity of essential oils was researched in vitro. MATERIAL AND METHODS: In this study, two standard fungal isolates Fusarium graminearum CCM F-683 and Fusarium graminearum CCM 8244 (Brno, Czech Republic) were used. The antifungal effect of 6 tested essential oils (Syzygium aromaticum, Origanum vulgare, Thymus vulgaris, Hyssopus officinalis , Ocimum basilicum, Myristica fragrans) was determined using the broth microdilution method, which allows reading of the MIC (minimum inhibitory concentration). According to the results obtained, the growth inhibition of Fusarium graminearum was determined by assay for the inhibition of radial growth of the mycelium. RESULTS: The inhibitory effects of thymus, oregano, basil, myristica, hyssop and syzygium essential oil (EO) on mycelial growth of Fusarium graminearum CCM F-683 and CCM 8244 were investigated. The best antifungal activity against the both strains of Fusarium graminearum (37.4%; 40.7%) was demonstrated by Origanum vulgare EO at the concentration 100 µg/mL. Among the four tested oils, three (Syzygium aromaticum, Thymus vulgaris, Origanum vulgare) achieved the best inhibitory effect (100%) at concentrations 500 µg/mL and 1000 µg/mL. CONCLUSIONS: In the protection of plants against pathogenic fungi, essential oils appear to be a suitable substitute for synthetic chemicals.


Assuntos
Fungicidas Industriais/farmacologia , Fusarium/efeitos dos fármacos , Óleos Voláteis/farmacologia , Óleos Vegetais/farmacologia , Fusarium/crescimento & desenvolvimento , Hyssopus/química , Testes de Sensibilidade Microbiana , Myristica/química , Ocimum basilicum/química , Origanum/química , Syzygium/química , Thymus (Planta)/química
2.
Int J Mol Sci ; 22(17)2021 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-34502209

RESUMO

The contamination of maize by Fusarium species able to produce mycotoxins raises great concern worldwide since they can accumulate these toxic metabolites in field crop products. Furthermore, little information exists today on the ability of Fusarium proliferatum and Fusarium graminearum, two well know mycotoxigenic species, to translocate from the seeds to the plants up to the kernels. Marketing seeds coated with fungicide molecules is a common practice; however, since there is a growing need for reducing chemicals in agriculture, new eco-friendly strategies are increasingly tested. Technologies based on ionized gases, known as plasmas, have been used for decades, with newer material surfaces, products, and approaches developed continuously. In this research, we tested a plasma-generated bilayer coating for encapsulating prothioconazole at the surface of maize seeds, to protect them from F. graminearum and F. proliferatum infection. A minimum amount of chemical was used, in direct contact with the seeds, with no dispersion in the soil. The ability of F. graminearum and F. proliferatum species to translocate from seeds to seedlings of maize has been clearly proven in our in vitro experiments. As for the use of plasma technology, the combined use of the plasma-generated coating with embedded prothioconazole was the most efficient approach, with a higher reduction of the infection of the maize seminal root system and stems. The debated capability of the two Fusarium species to translocate from seeds to seedlings has been demonstrated. The plasma-generated coating with embedded prothioconazole resulted in a promising sustainable approach for the protection of maize seedlings.


Assuntos
Contaminação de Alimentos/análise , Fungicidas Industriais/farmacologia , Fusarium/crescimento & desenvolvimento , Gases em Plasma/farmacologia , Plântula/crescimento & desenvolvimento , Triazóis/farmacologia , Zea mays/crescimento & desenvolvimento , Contaminação de Alimentos/prevenção & controle , Fusarium/efeitos dos fármacos , Plântula/efeitos dos fármacos , Plântula/microbiologia , Zea mays/efeitos dos fármacos , Zea mays/microbiologia
3.
Biomed Res Int ; 2021: 9930210, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34395628

RESUMO

The present study was aimed at isolating endophytic fungi from the Asian culinary and medicinal plant Lilium davidii and analyzing its antifungal and plant growth-promoting effects. In this study, the fungal endophyte Acremonium sp. Ld-03 was isolated from the bulbs of L. davidii and identified through morphological and molecular analysis. The molecular and morphological analysis confirmed the endophytic fungal strain as Acremonium sp. Ld-03. Antifungal effects of Ld-03 were observed against Fusarium oxysporum, Botrytis cinerea, Botryosphaeria dothidea, and Fusarium fujikuroi. The highest growth inhibition, i.e., 78.39 ± 4.21%, was observed for B. dothidea followed by 56.68 ± 4.38%, 43.62 ± 3.81%, and 20.12 ± 2.45% for B. cinerea, F. fujikuroi, and F. oxysporum, respectively. Analysis of the ethyl acetate fraction through UHPLC-LTQ-IT-MS/MS revealed putative secondary metabolites which included xanthurenic acid, valyl aspartic acid, gancidin W, peptides, and cyclic dipeptides such as valylarginine, cyclo-[L-(4-hydroxy-Pro)-L-leu], cyclo(Pro-Phe), and (3S,6S)-3-benzyl-6-(4-hydroxybenzyl)piperazine-2,5-dione. Other metabolites included (S)-3-(4-hydroxyphenyl)-2-((S)-pyrrolidine-2-carboxamido)propanoic acid, dibutyl phthalate (DBP), 9-octadecenamide, D-erythro-C18-Sphingosine, N-palmitoyl sphinganine, and hydroxypalmitoyl sphinganine. The strain Ld-03 showed indole acetic acid (IAA) production with or without the application of exogenous tryptophan. The IAA ranged from 53.12 ± 3.20 µg ml-1 to 167.71 ± 7.12 µg ml-1 under different tryptophan concentrations. The strain was able to produce siderophore, and its production was significantly decreased with increasing Fe(III) citrate concentrations in the medium. The endophytic fungal strain also showed production of organic acids and phosphate solubilization activity. Plant growth-promoting effects of the strain were evaluated on in vitro seedling growth of Allium tuberosum. Application of 40% culture dilution resulted in a significant increase in root and shoot length, i.e., 24.03 ± 2.71 mm and 37.27 ± 1.86 mm, respectively, compared to nontreated control plants. The fungal endophyte Ld-03 demonstrated the potential of conferring disease resistance and plant growth promotion. Therefore, we conclude that the isolated Acremonium sp. Ld-03 should be further investigated before utilization as a biocontrol agent and plant growth stimulator.


Assuntos
Acremonium/química , Antifúngicos/farmacologia , Ascomicetos/crescimento & desenvolvimento , Botrytis/crescimento & desenvolvimento , Fusarium/crescimento & desenvolvimento , Lilium/microbiologia , Reguladores de Crescimento de Plantas/farmacologia , Acetatos/química , Acetatos/farmacologia , Acremonium/isolamento & purificação , Acremonium/fisiologia , Antifúngicos/química , Ascomicetos/efeitos dos fármacos , Botrytis/efeitos dos fármacos , Cebolinha-Francesa/efeitos dos fármacos , Cebolinha-Francesa/crescimento & desenvolvimento , Cromatografia Líquida de Alta Pressão , Resistência à Doença , Endófitos/isolamento & purificação , Endófitos/fisiologia , Fusarium/efeitos dos fármacos , Ácidos Indolacéticos/química , Ácidos Indolacéticos/isolamento & purificação , Ácidos Indolacéticos/farmacologia , Metabolômica/métodos , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos , Desenvolvimento Vegetal , Reguladores de Crescimento de Plantas/química , Reguladores de Crescimento de Plantas/isolamento & purificação , Raízes de Plantas/microbiologia , Metabolismo Secundário , Espectrometria de Massas em Tandem
4.
Molecules ; 26(16)2021 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-34443447

RESUMO

Okara is a soybean transformation agri-food by-product, the massive production of which currently poses severe disposal issues. However, its composition is rich in seed storage proteins, which, once extracted, can represent an interesting source of bioactive peptides. Antimicrobial and antifungal proteins and peptides have been described in plant seeds; thus, okara is a valuable source of compounds, exploitable for integrated pest management. The aim of this work is to describe a rapid and economic procedure to isolate proteins from okara, and to produce an enzymatic proteolyzed product, active against fungal plant pathogens. The procedure allowed the isolation and recovery of about 30% of okara total proteins. Several proteolytic enzymes were screened to identify the proper procedure to produce antifungal compounds. Antifungal activity of the protein digested for 24 h with pancreatin against Fusarium and R. solani mycelial growth and Pseudomonas spp was assessed. A dose-response inhibitory activity was established against fungi belonging to the Fusarium genus. The exploitation of okara to produce antifungal bioactive peptides has the potential to turn this by-product into a paradigmatic example of circular economy, since a field-derived food waste is transformed into a source of valuable compounds to be used in field crops protection.


Assuntos
Antifúngicos/farmacologia , Enzimas/metabolismo , Proteínas de Plantas/metabolismo , Plantas/microbiologia , Polissacarídeos/metabolismo , Liofilização , Fusarium/efeitos dos fármacos , Fusarium/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Peso Molecular , Proteólise/efeitos dos fármacos , Alimentos de Soja , Espectrofotometria Ultravioleta , Tripsina/metabolismo , Inibidores da Tripsina/farmacologia
5.
Appl Environ Microbiol ; 87(20): e0096721, 2021 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-34378994

RESUMO

The plant pathogen Fusarium graminearum contains two α-tubulin isotypes (α1 and α2) and two ß-tubulin isotypes (ß1 and ß2). The functional roles of these tubulins in microtubule assembly are not clear. Previous studies reported that α1- and ß2-tubulin deletion mutants showed severe growth defects and hypersensitivity to carbendazim, which have not been well explained. Here, we investigated the interaction between α- and ß-tubulin of F. graminearum. Colocalization experiments demonstrated that ß1- and ß2-tubulin are colocalized. Coimmunoprecipitation experiments suggested that ß1-tubulin binds to both α1- and α2-tubulin and that ß2-tubulin can also bind to α1- or α2-tubulin. Interestingly, deletion of α1-tubulin increased the interaction between ß2-tubulin and α2-tubulin. Microtubule observation assays showed that deletion of α1-tubulin completely disrupted ß1-tubulin-containing microtubules and significantly decreased ß2-tubulin-containing microtubules. Deletion of α2-, ß1-, or ß2-tubulin had no obvious effect on the microtubule cytoskeleton. However, microtubules in α1- and ß2-tubulin deletion mutants were easily depolymerized in the presence of carbendazim. The sexual reproduction assay indicates that α1- and ß1-tubulin deletion mutants could not produce asci and ascospores. These results implied that α1-tubulin may be essential for the microtubule cytoskeleton. However, our Δα1-2×α2 mutant (α1-tubulin deletion mutant containing two copies of α2-tubulin) exhibited normal microtubule network, growth, and sexual reproduction. Interestingly, the Δα1-2×α2 mutant was still hypersensitive to carbendazim. In addition, both ß1-tubulin and ß2-tubulin were found to bind the mitochondrial outer membrane voltage-dependent anion channel (VDAC), indicating that they could regulate the function of VDAC. IMPORTANCE In this study, we found that F. graminearum contains four different α-/ß-tubulin heterodimers (α1-/ß1-, α1-/ß2-, α2-/ß1-, and α2-/ß2-tubulin heterodimers), and they assemble together into a single microtubule. Moreover, α1- and α2-tubulins are functionally interchangeable in microtubule assembly, vegetative growth, and sexual reproduction. These results provide more insights into the functional roles of different tubulins of F. graminearum, which could be helpful for purification of tubulin heterodimers and development of new tubulin-binding agents.


Assuntos
Fusarium/fisiologia , Microtúbulos/fisiologia , Tubulina (Proteína)/fisiologia , Proteínas Fúngicas/fisiologia , Fusarium/genética , Fusarium/crescimento & desenvolvimento , Canais de Ânion Dependentes de Voltagem/fisiologia
6.
Molecules ; 26(13)2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34208916

RESUMO

Vascular wilt caused by F. oxysporum (FOX) is one of the main limitations of producing several agricultural products worldwide, causing economic losses between 40% and 100%. Various methods have been developed to control this phytopathogen, such as the cultural, biological, and chemical controls, the latter being the most widely used in the agricultural sector. The treatment of this fungus through systemic fungicides, although practical, brings problems because the agrochemical agents used have shown mutagenic effects on the fungus, increasing the pathogen's resistance. The design and the synthesis of novel synthetic antifungal agents used against FOX have been broadly studied in recent years. This review article presents a compendium of the synthetic methodologies during the last ten years as promissory, which can be used to afford novel and potential agrochemical agents. The revision is addressed from the structural core of the most active synthetic compounds against FOX. The synthetic methodologies implemented strategies based on cyclo condensation reactions, radical cyclization, electrocyclic closures, and carbon-carbon couplings by metal-organic catalysis. This revision contributes significantly to the organic chemistry, supplying novel alternatives for the use of more effective agrochemical agents against F. oxysporum.


Assuntos
Agricultura , Antifúngicos , Fusarium/crescimento & desenvolvimento , Doenças das Plantas/microbiologia , Antifúngicos/síntese química , Antifúngicos/química , Antifúngicos/farmacologia
7.
Molecules ; 26(13)2021 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34202905

RESUMO

Cereals are subject to contamination by pathogenic fungi, which damage grains and threaten public health with their mycotoxins. Fusarium graminearum and its mycotoxins, trichothecenes B (TCTBs), are especially targeted in this study. Recently, the increased public and political awareness concerning environmental issues tends to limit the use of traditional fungicides against these pathogens in favor of eco-friendlier alternatives. This study focuses on the development of biofungicides based on the encapsulation of a curcumin derivative, tetrahydrocurcumin (THC), in polysaccharide matrices. Starch octenylsuccinate (OSA-starch) and chitosan have been chosen since they are generally recognized as safe. THC has been successfully trapped into particles obtained through a spray-drying or freeze-drying processes. The particles present different properties, as revealed by visual observations and scanning electron microscopy. They are also different in terms of the amount and the release of encapsulated THC. Although freeze-dried OSA-starch has better trapped THC, it seems less able to protect the phenolic compound than spray-dried particles. Chitosan particles, both spray-dried and lyophilized, have shown promising antifungal properties. The IC50 of THC-loaded spray-dried chitosan particles is as low as 0.6 ± 0.3 g/L. These particles have also significantly decreased the accumulation of TCTBs by 39%.


Assuntos
Antifúngicos , Agentes de Controle Biológico , Quitosana , Fusarium/crescimento & desenvolvimento , Amido/análogos & derivados , Antifúngicos/química , Antifúngicos/farmacologia , Agentes de Controle Biológico/química , Agentes de Controle Biológico/farmacologia , Quitosana/química , Quitosana/farmacologia , Curcumina/análogos & derivados , Curcumina/química , Curcumina/farmacologia , Amido/química , Amido/farmacologia
8.
PLoS One ; 16(7): e0254170, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34293008

RESUMO

Several species of Fusarium cause serious diseases in date palm worldwide. In the present work, 14 SSR markers were used to assess the genetic variation of Fusarium strains isolated from diseased trees in Saudi Arabia. We also studied the effect of different temperatures on mycelial growth of these strains. The pathogenicity of four strains of F. proliferatum was also evaluated on local date palm cultivars. Eleven SSR markers amplified a total of 57 scorable alleles from Fusarium strains. Phylogenetic analysis showed that F. proliferatum strains grouped in one clade with 95% bootstrap value. Within F. proliferatum clade, 14 SSR genotypes were identified, 9 of them were singleton. Four out of the five multi-individual SSR genotypes contained strains isolated from more than one location. Most F. solani strains grouped in one clade with 95% bootstrap value. Overall, the SSR markers previously developed for F. verticillioides and F. oxysporum were very useful in assessing the genetic diversity and confirming the identity of Saudi Fusarium strains. The results from the temperature study showed significant differences in mycelial growth of Fusarium strains at different temperatures tested. The highest average radial growth for Fusarium strains was observed at 25°C, irrespective of species. The four F. proliferatum strains showed significant differences in their pathogenicity on date palm cultivars. It is anticipated that the assessment of genetic diversity, effect of temperature on hyphal growth and pathogenicity of potent pathogenic Fusarium strains recovered from date palm-growing locations in Saudi Arabia can help in effectively controlling these pathogens.


Assuntos
Fusarium , Variação Genética , Genótipo , Phoeniceae/microbiologia , Filogenia , Doenças das Plantas , Alelos , Fusarium/genética , Fusarium/crescimento & desenvolvimento , Fusarium/patogenicidade , Phoeniceae/genética , Doenças das Plantas/genética , Doenças das Plantas/microbiologia
9.
PLoS One ; 16(7): e0250064, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34329342

RESUMO

The ascomycete fungus Fusarium oxysporum f.sp. cucumerinum causes vascular wilt diseases in cucumber. However, few genes related to morphogenesis and pathogenicity of this fungal pathogen have been functionally characterized. BLASTp searches of the Aspergillus fumigatus UgmA and galatofuranosyltransferases (Galf-transferases) sequences in the F. oxysporum genome identified two genes encoding putative UDP-galactopyranose mutase (UGM), ugmA and ugmB, and six genes encoding putative Galf-transferase homologs. In this study, the single and double mutants of the ugmA, ugmB and gfsB were obtained. The roles of UGMs and GfsB were investigated by analyzing the phenotypes of the mutants. Our results showed that deletion of the ugmA gene led to a reduced production of galactofuranose-containing sugar chains, reduced growth and impaired conidiation of F. oxysporum f.sp. cucumerinum. Most importantly, the ugmA deletion mutant lost the pathogenicity in cucumber plantlets. Although deletion of the ugmB gene did not cause any visible phenotype, deletion of both ugmA and ugmB genes caused more severe phenotypes as compared with the ΔugmA, suggesting that UgmA and UgmB are redundant and they can both contribute to synthesis of UDP-Galf. Furthermore, the ΔgfsB exhibited an attenuated virulence although no other phenotype was observed. Our results demonstrate that the galactofuranose (Galf) synthesis contributes to the cell wall integrity, germination, hyphal growth, conidiation and virulence in Fusarium oxysporum f.sp. cucumerinum and an ideal target for the development of new anti-Fusarium agents.


Assuntos
Fusarium/genética , Galactose/metabolismo , Virulência/genética , Aspergillus nidulans/enzimologia , Cucumis sativus/microbiologia , Proteínas Fúngicas/classificação , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Fusarium/crescimento & desenvolvimento , Fusarium/patogenicidade , Galactose/análise , Hifas/genética , Hifas/crescimento & desenvolvimento , Transferases Intramoleculares/classificação , Transferases Intramoleculares/genética , Transferases Intramoleculares/metabolismo , Mananas/análise , Mananas/metabolismo , Mutagênese , Fenótipo , Filogenia , Doenças das Plantas/microbiologia
10.
Int J Food Microbiol ; 353: 109297, 2021 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-34153829

RESUMO

The Fusarium incarnatum-equiseti species complex (FIESC) is a phylogenetically rich complex. It includes more than 30 cryptic phylogenetic species, making morphological identification problematic. FIESC has previously been detected in Tunisian cereals, but knowledge on the phylogeny and the ecophysiology of their species is lacking. In this work a phylogenetic analysis was performed using partial sequences of the translation elongation factor 1a gene (EF1a) of three FIESC strains isolated from barley and wheat from Tunisia, situated south in the Mediterranean basin, and additional strains from other countries. The results indicated that all Tunisian strains clustered with FIESC 5 group (F. clavum) together with other Spanish FIESC 5 strains also isolated from cereals. Growth rate profiles of the Tunisian strains were also determined on wheat and sorghum based media at a range of temperatures (15, 20, 25, 30, 35 and 40 °C) and water potential values (-0.7, -2.8, -7.0, and -9.8 MPa, corresponding to 0.995, 0.98, 0.95 and 0.93 aw values). Optimal growth was observed at 20-30 °C and between -0.7 and -7.0 MPa on both substrates (wheat and sorghum). The highest growth rate for the three strains was seen at 25 °C combined with -2.8 MPa. The comparison between the growth profiles of Tunisian and Spanish FIESC 5 strains showed similar trends with some interesting differences regarding temperature and water potential factors. Tunisian strains seem to perform better between 15 and 30 °C and, notably, at even lower water potentials included -9.8 Mpa. This might suggest that tolerance to low water potentials might be for Tunisian strains a more important selective clue than to higher temperatures. These results appeared to be consistent with a population well adapted to the present climatic conditions and predicted scenarios for North Africa.


Assuntos
Grão Comestível , Fusarium , Hordeum , Filogenia , Triticum , Grão Comestível/microbiologia , Fusarium/classificação , Fusarium/genética , Fusarium/crescimento & desenvolvimento , Fusarium/isolamento & purificação , Hordeum/microbiologia , Fatores de Alongamento de Peptídeos/genética , Triticum/microbiologia , Tunísia
11.
Microbiol Res ; 249: 126770, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33932742

RESUMO

Trichoderma species are well known for producing various secondary metabolites in response to different fungal pathogens. This paper reports the effects of the metabolites produced during one-day cultivation of Trichoderma harzianum on the growth and development of the popular pathogen Fusarium culmorum. Inhibition of the growth of the pathogen and production of secondary metabolites including zearalenone was observed on Petri dishes. The presence of proteins such as cytochrome c oxidase subunit 4, glutathione-independent glyoxalase HSP31, and putative peroxiredoxin pmp20 in the extract-treated culture indicated oxidative stress, which was confirmed by the presence of a higher amount of catalase and dismutase in the later hours of the culture. A larger amount of enolase and glyceraldehyde 3-phosphate dehydrogenase resulted in faster growth, and the overexpression of stress protein and Woronin body major protein indicated the activation of defense mechanisms. In addition, a cardinal reduction in major mycotoxin production was noted.


Assuntos
Antibiose , Proteínas Fúngicas/metabolismo , Fusarium/crescimento & desenvolvimento , Fusarium/metabolismo , Hypocreales/metabolismo , Meios de Cultura , Metaboloma , Micotoxinas/metabolismo , Estresse Oxidativo , Pigmentos Biológicos/metabolismo , Proteoma , Metabolismo Secundário , Zearalenona/metabolismo
12.
World J Microbiol Biotechnol ; 37(6): 93, 2021 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-33948741

RESUMO

Chlorogenic acid is a plant polyphenol with antioxidant and antimicrobial activities. Fusarium fujikuroi is a fungal pathogen that causes many vegetables and fruits, including tomato, to rot. The effects of chlorogenic acid on the development of Fusarium rot of cherry tomato fruit were examined in the present study. Results showed that conidial germination, germ tube elongation, cell viability, and mycelial growth of F. fujikuroi were all significantly inhibited by chlorogenic acid. Chlorogenic acid stimulated the accumulation of reactive oxygen species (ROS), leading to cell apoptosis in F. fujikuroi. The addition of N-acetylcysteine partially recovered the mycelial growth, implying the antifungal activity of chlorogenic acid is related to a ROS burst. The application of chlorogenic acid decreased disease incidence and severity in cherry tomato fruit in a concentration-dependent manner. Taken together, these results suggest that chlorogenic acid inhibits the postharvest rot of cherry tomato fruit caused by F. fujikuroi by inducing cellular oxidative stress in the pathogen.


Assuntos
Ácido Clorogênico/farmacologia , Fusarium/crescimento & desenvolvimento , Lycopersicon esculentum/crescimento & desenvolvimento , Acetilcisteína/farmacologia , Relação Dose-Resposta a Droga , Fusarium/efeitos dos fármacos , Fusarium/metabolismo , Lycopersicon esculentum/microbiologia , Viabilidade Microbiana/efeitos dos fármacos , Micélio/efeitos dos fármacos , Doenças das Plantas/prevenção & controle , Espécies Reativas de Oxigênio/metabolismo , Esporos Fúngicos/efeitos dos fármacos
13.
Methods Mol Biol ; 2309: 105-111, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34028682

RESUMO

Current knowledge on the mechanism of strigolactones (SLs) as signaling molecules during specific interactions in the rhizosphere is mainly related to the control of germination of parasitic weed seeds and hyphal branching of arbuscular mycorrhizal fungi. Thus, the role of plant secreted SLs in regulating the growth and development of root-colonizing fungi still remains controversial. Fusarium oxysporum can sense and respond to extracellular signals through oriented germ tube emergence and redirectioning of hyphal growth toward gradients of nutrients, sex pheromones, or plant root exudates. However, chemoattractant activity of SLs against microorganisms living in the soil has not been tested so far. Here we propose a quantitative chemotropic assay to understand if and how soil fungi could sense gradients of SLs and SLs-like sources. In the example case of F. oxysporum, hyphae of fungal representative mutants preferentially grow toward the synthetic SL analog GR24; and this chemotropic response requires conserved elements of the fungal invasive growth mitogen-activated protein kinase (MAPK) cascade.


Assuntos
Fusarium/efeitos dos fármacos , Compostos Heterocíclicos com 3 Anéis/farmacologia , Lactonas/farmacologia , Reguladores de Crescimento de Plantas/farmacologia , Raízes de Plantas/microbiologia , Microbiologia do Solo , Tropismo/efeitos dos fármacos , Fusarium/crescimento & desenvolvimento , Fusarium/metabolismo
14.
Sci Rep ; 11(1): 7962, 2021 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-33846413

RESUMO

Fusarium graminearum is a major fungal pathogen affecting crops of worldwide importance. F. graminearum produces type B trichothecene mycotoxins (TCTB), which are not fully eliminated during food and feed processing. Therefore, the best way to minimize TCTB contamination is to develop prevention strategies. Herein we show that treatment with the reduced form of the γ-core of the tick defensin DefMT3, referred to as TickCore3 (TC3), decreases F. graminearum growth and abrogates TCTB production. The oxidized form of TC3 loses antifungal activity, but retains anti-mycotoxin activity. Molecular dynamics show that TC3 is recruited by specific membrane phospholipids in F. graminearum and that membrane binding of the oxidized form of TC3 is unstable. Capping each of the three cysteine residues of TC3 with methyl groups reduces its inhibitory efficacy. Substitutions of the positively-charged residues lysine (Lys) 6 or arginine 7 by threonine had the highest and the lesser impact, respectively, on the anti-mycotoxin activity of TC3. We conclude that the binding of linear TC3 to F. graminearum membrane phospholipids is required for the antifungal activity of the reduced peptide. Besides, Lys6 appears essential for the anti-mycotoxin activity of the reduced peptide. Our results provide foundation for developing novel and environment-friendly strategies for controlling F. graminearum.


Assuntos
Defensinas/farmacologia , Fusarium/crescimento & desenvolvimento , Micotoxinas/biossíntese , Carrapatos/metabolismo , Sequência de Aminoácidos , Animais , Antifúngicos/farmacologia , Cisteína/metabolismo , Lipídeos de Membrana/metabolismo , Metilação , Peptídeos/química , Fosfolipídeos/metabolismo , Ligação Proteica
15.
Pol J Microbiol ; 70(1): 131-136, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33815534

RESUMO

In dual culture confrontation assays, basidiomycete Irpex lacteus efficiently antagonized Fusarium spp., Colletotrichum spp., and Phytophthora spp. phytopathogenic strains, with growth inhibition percentages between 16.7-46.3%. Antibiosis assays evaluating the inhibitory effect of soluble extracellular metabolites indicated I. lacteus strain inhibited phytopathogens growth between 32.0-86.7%. Metabolites in the extracellular broth filtrate, identified by UPLC-QTOF mass spectrometer, included nine terpenes, two aldehydes, and derivatives of a polyketide, a quinazoline, and a xanthone, several of which had antifungal activity. I. lacteus strain and its extracellular metabolites might be valuable tools for phytopathogenic fungi and oomycete biocontrol of agricultural relevance.


Assuntos
Antifúngicos/farmacologia , Fusarium/efeitos dos fármacos , Oomicetos/efeitos dos fármacos , Phytophthora/efeitos dos fármacos , Doenças das Plantas/microbiologia , Polyporales/química , Aldeídos/química , Aldeídos/metabolismo , Aldeídos/farmacologia , Antifúngicos/química , Antifúngicos/metabolismo , Fusarium/crescimento & desenvolvimento , Espectrometria de Massas , Oomicetos/crescimento & desenvolvimento , Phytophthora/crescimento & desenvolvimento , Polyporales/metabolismo , Quinazolinas/química , Quinazolinas/metabolismo , Quinazolinas/farmacologia , Terpenos/química , Terpenos/metabolismo , Terpenos/farmacologia
16.
Toxins (Basel) ; 13(3)2021 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-33803037

RESUMO

Deoxynivalenol (DON), a trichothecene mycotoxin produced by Fusarium species, is the most widespread mycotoxin in poultry feed worldwide. Long term-exposure from low to moderate DON concentrations can produce alteration in growth performance and impairment of the health status of birds. To evaluate the efficacy of mycotoxin-detoxifying agent alleviating the toxic effects of DON, the most relevant biomarkers of toxicity of DON in chickens should be firstly determined. The specific biomarker of exposure of DON in chickens is DON-3 sulphate found in different biological matrices (plasma and excreta). Regarding the nonspecific biomarkers called also biomarkers of effect, the most relevant ones are the impairment of the productive parameters, the intestinal morphology (reduction of villus height) and the enlargement of the gizzard. Moreover, the biomarkers of effect related to physiology (decrease of blood proteins, triglycerides, hemoglobin, erythrocytes, and lymphocytes and the increase of alanine transaminase (ALT)), immunity (response to common vaccines and release of some proinflammatory cytokines) and welfare status of the birds (such as the increase of Thiobarbituric acid reactive substances (TBARS) and the stress index), has been reported. This review highlights the available information regarding both types of biomarkers of DON toxicity in chickens.


Assuntos
Ração Animal/microbiologia , Bem-Estar do Animal , Galinhas/crescimento & desenvolvimento , Metabolismo Energético , Microbiologia de Alimentos , Fusarium/metabolismo , Tricotecenos/toxicidade , Criação de Animais Domésticos , Animais , Biomarcadores/sangue , Galinhas/imunologia , Galinhas/metabolismo , Fusarium/crescimento & desenvolvimento , Nível de Saúde , Fatores de Tempo , Tricotecenos/metabolismo
17.
Toxins (Basel) ; 13(3)2021 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-33809408

RESUMO

The levels of fumonisins (FUMO)-mycotoxins produced by Fusarium verticillioides-in maize for food and feed are subject to European Union regulations. Compliance with the regulations requires the targeting of, among others, the agroclimatic factors influencing fungal contamination and FUMO production. Arvalis-Institut du végétal has created a national, multiyear database for maize, based on field survey data collected since 2003. This database contains information about agricultural practices, climatic conditions and FUMO concentrations at harvest for 738 maize fields distributed throughout French maize-growing regions. A linear mixed model approach highlights the presence of borers and the use of a late variety, high temperatures in July and October, and a water deficit during the maize cycle as creating conditions favoring maize contamination with Fusarium verticillioides. It is thus possible to target a combination of risk factors, consisting of this climatic sequence associated with agricultural practices of interest. The effects of the various possible agroclimatic combinations can be compared, grouped and classified as promoting very low to high FUMO concentrations, possibly exceeding the regulatory threshold. These findings should facilitate the creation of a national, informative and easy-to-use prevention tool for producers and agricultural cooperatives to manage the sanitary quality of their harvest.


Assuntos
Clima , Proteção de Cultivos , Contaminação de Alimentos/prevenção & controle , Microbiologia de Alimentos , Fumonisinas/análise , Fusarium/metabolismo , Zea mays/microbiologia , Irrigação Agrícola , Bases de Dados Factuais , França , Fumonisinas/toxicidade , Fusarium/crescimento & desenvolvimento , Estado de Hidratação do Organismo , Medição de Risco , Fatores de Risco , Temperatura , Fatores de Tempo
18.
Molecules ; 26(7)2021 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-33806149

RESUMO

Bacillus subtilis SH21 was observed to produce an antifungal protein that inhibited the growth of F. solani. To purify this protein, ammonium sulfate precipitation, gel filtration chromatography, and ion-exchange chromatography were used. The purity of the purified product was 91.33% according to high-performance liquid chromatography results. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis and liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis revealed that the molecular weight of the protein is 30.72 kDa. The results of the LC-MS/MS analysis and a subsequent sequence-database search indicated that this protein was a chitosanase, and thus, we named it chitosanase SH21. Scanning and transmission electron microscopy revealed that chitosanase SH21 appeared to inhibit the growth of F. solani by causing hyphal ablation, distortion, or abnormalities, and cell-wall depression. The minimum inhibitory concentration of chitosanase SH21 against F. solani was 68 µg/mL. Subsequently, the corresponding gene was cloned and sequenced, and sequence analysis indicated an open reading frame of 831 bp. The predicted secondary structure indicated that chitosanase SH21 has a typical a-helix from the glycoside hydrolase (GH) 46 family. The tertiary structure shared 40% similarity with that of Streptomyces sp. N174. This study provides a theoretical basis for a topical cream against fungal infections in agriculture and a selection marker on fungi.


Assuntos
Antifúngicos , Bacillus subtilis/enzimologia , Proteínas de Bactérias , Fusarium/crescimento & desenvolvimento , Glicosídeo Hidrolases , Antifúngicos/química , Antifúngicos/isolamento & purificação , Antifúngicos/farmacologia , Proteínas de Bactérias/química , Proteínas de Bactérias/isolamento & purificação , Proteínas de Bactérias/farmacologia , Glicosídeo Hidrolases/química , Glicosídeo Hidrolases/isolamento & purificação , Glicosídeo Hidrolases/farmacologia
19.
Int J Food Microbiol ; 347: 109171, 2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-33872940

RESUMO

Potatoes contain several nutrients essential for fungal growth, making them an excellent component of media such as the popular Potato Dextrose Agar (PDA) medium. Commercially, PDA is available from multiple retailers offering virtually the same product. These media, however, could contain small differences in composition of nutrients affecting the expression of secondary metabolites. This study aims to investigate the use of four PDA media from different manufacturers (Fluka, Oxoid, Sigma, and VWR) and their effect on the metabolite profile of four species of Fusarium (F. fujikuroi, F. graminearum, F. pseudograminearum and F. avenaceum). Secondary metabolites were analysed using HPLC-HRMS, from which statistically significant differences in intensities were observed for 9 out of 10 metabolites.


Assuntos
Meios de Cultura/química , Fusarium/metabolismo , Glucose/metabolismo , Solanum tuberosum/química , Ágar/metabolismo , Meios de Cultura/metabolismo , Fusarium/classificação , Fusarium/crescimento & desenvolvimento , Metabolismo Secundário/fisiologia
20.
Plant Cell ; 33(2): 224-247, 2021 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-33681966

RESUMO

The broad host range of Fusarium virguliforme represents a unique comparative system to identify and define differentially induced responses between an asymptomatic monocot host, maize (Zea mays), and a symptomatic eudicot host, soybean (Glycine max). Using a temporal, comparative transcriptome-based approach, we observed that early gene expression profiles of root tissue from infected maize suggest that pathogen tolerance coincides with the rapid induction of senescence dampening transcriptional regulators, including ANACs (Arabidopsis thaliana NAM/ATAF/CUC protein) and Ethylene-Responsive Factors. In contrast, the expression of senescence-associated processes in soybean was coincident with the appearance of disease symptom development, suggesting pathogen-induced senescence as a key pathway driving pathogen susceptibility in soybean. Based on the analyses described herein, we posit that root senescence is a primary contributing factor underlying colonization and disease progression in symptomatic versus asymptomatic host-fungal interactions. This process also supports the lifestyle and virulence of F. virguliforme during biotrophy to necrotrophy transitions. Further support for this hypothesis lies in comprehensive co-expression and comparative transcriptome analyses, and in total, supports the emerging concept of necrotrophy-activated senescence. We propose that F. virguliforme conditions an environment within symptomatic hosts, which favors susceptibility through transcriptomic reprogramming, and as described herein, the induction of pathways associated with senescence during the necrotrophic stage of fungal development.


Assuntos
Fusarium/fisiologia , Interações Hospedeiro-Patógeno/genética , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Soja/microbiologia , Transcrição Genética , Zea mays/microbiologia , Contagem de Colônia Microbiana , Fusarium/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Soja/genética , Fatores de Tempo , Fatores de Transcrição/metabolismo , Transcriptoma/genética , Zea mays/genética
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