RESUMO
BACKGROUND: Sophorolipids are glycolipid biosurfactants with potential antibacterial, antifungal, and anticancer applications, rendering them promising for research. Therefore, this study hypothesizes that sophorolipids may have a notable impact on disrupting membrane integrity and triggering the production of reactive oxygen species, ultimately resulting in the eradication of pathogenic microbes. RESULTS: The current study resulted in the isolation of two Metschnikowia novel yeast strains. Sophorolipids production from these strains reached maximum yields of 23.24 g/l and 21.75 g/l, respectively, at the bioreactors level. Biosurfactants sophorolipids were characterized using FTIR and LC-MS techniques and found to be a mixture of acidic and lactonic forms with molecular weights of m/z 678 and 700. Our research elucidated sophorolipids' mechanism in disrupting bacterial and fungal membranes through ROS generation, confirmed by transmission electron microscopy and FACS analysis. The results showed that these compounds disrupted the membrane integrity and induced ROS production, leading to cell death in Klebsiella pneumoniae and Fusarium solani. In addition, the anticancer properties of sophorolipids were investigated on the A549 lung cancer cell line and found that sophorolipid-11D (SL-11D) and sophorolipid-11X (SL-11X) disrupted the actin cytoskeleton, as evidenced by immunofluorescence microscopy. The A549 cells were stained with Acridine orange/Ethidium bromide, which showed that they underwent necrosis. This was confirmed by flow cytometric analysis using Annexin/PI staining. The SL-11D and SL-11X molecules exhibited low levels of haemolytic activity and in-vitro cytotoxicity in HEK293, Caco-2, and L929 cell lines. CONCLUSION: In this work, novel yeast species CIG-11DT and CIG-11XT, isolated from the bee's gut, produce significant yields of sophorolipids without needing secondary oil sources, indicating a more economical production method. Our research shows that sophorolipids disrupt bacterial and fungal membranes via ROS production. They suggest they may act as chemo-preventive agents by inducing apoptosis in lung cancer cells, offering the potential for enhancing anticancer therapies.
Assuntos
Antifúngicos , Antineoplásicos , Metschnikowia , Estresse Oxidativo , Espécies Reativas de Oxigênio , Tensoativos , Antifúngicos/farmacologia , Antifúngicos/química , Antifúngicos/metabolismo , Humanos , Tensoativos/farmacologia , Tensoativos/metabolismo , Tensoativos/química , Estresse Oxidativo/efeitos dos fármacos , Antineoplásicos/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Células A549 , Metschnikowia/metabolismo , Metschnikowia/efeitos dos fármacos , Fusarium/efeitos dos fármacos , Fusarium/metabolismo , Klebsiella pneumoniae/efeitos dos fármacos , Glicolipídeos/farmacologia , Glicolipídeos/metabolismo , Testes de Sensibilidade Microbiana , Ácidos OleicosRESUMO
BACKGROUND: ââThe genus Fusarium poses significant threats to food security and safety worldwide because numerous species of the fungus cause destructive diseases and/or mycotoxin contamination in crops. The adverse effects of climate change are exacerbating some existing threats and causing new problems. These challenges highlight the need for innovative solutions, including the development of advanced tools to identify targets for control strategies. DESCRIPTION: In response to these challenges, we developed the Fusarium Protein Toolkit (FPT), a web-based tool that allows users to interrogate the structural and variant landscape within the Fusarium pan-genome. The tool displays both AlphaFold and ESMFold-generated protein structure models from six Fusarium species. The structures are accessible through a user-friendly web portal and facilitate comparative analysis, functional annotation inference, and identification of related protein structures. Using a protein language model, FPT predicts the impact of over 270 million coding variants in two of the most agriculturally important species, Fusarium graminearum and F. verticillioides. To facilitate the assessment of naturally occurring genetic variation, FPT provides variant effect scores for proteins in a Fusarium pan-genome based on 22 diverse species. The scores indicate potential functional consequences of amino acid substitutions and are displayed as intuitive heatmaps using the PanEffect framework. CONCLUSION: FPT fills a knowledge gap by providing previously unavailable tools to assess structural and missense variation in proteins produced by Fusarium. FPT has the potential to deepen our understanding of pathogenic mechanisms in Fusarium, and aid the identification of genetic targets for control strategies that reduce crop diseases and mycotoxin contamination. Such targets are vital to solving the agricultural problems incited by Fusarium, particularly evolving threats resulting from climate change. Thus, FPT has the potential to contribute to improving food security and safety worldwide.
Assuntos
Proteínas Fúngicas , Fusarium , Internet , Fusarium/genética , Fusarium/metabolismo , Fusarium/classificação , Proteínas Fúngicas/genética , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Genoma Fúngico/genética , Variação Genética , Modelos Moleculares , Software , Conformação ProteicaRESUMO
Transposon mutagenesis screening of Bacillus subtilis YB-1471, a novel rhizosphere biocontrol agent of Fusarium crown rot (FCR) of wheat, resulted in the identification of orf04391, linked to reduced biofilm formation. The gene encodes a protein possessing a putative tertiary structure of a "double-wing" DNA-binding domain. Expression of orf04391 increased during biofilm development in stationary cultures and during rapid growth in shaking cultures. An orf04391 deletion strain showed reduced biofilm production related to lower levels of the extracellular matrix, and the mutant also had reduced sporulation, adhesion, root colonization, and FCR biocontrol efficiency. Transcriptome analysis of YB-1471 and Δorf04391 in stationary culture showed that the loss of orf04391 resulted in altered expression of numerous genes, including sinI, an initiator of biofilm formation. DNA binding was shown with his-tagged Orf04391 binding to the sinIR operon in vivo and in vitro. Orf04391 appears to be a transcriptional regulator of biofilm formation in B. subtilis through the Spo0A-SinI/SinR pathway.
Assuntos
Bacillus subtilis , Proteínas de Bactérias , Fusarium , Doenças das Plantas , Triticum , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/química , Biofilmes/crescimento & desenvolvimento , Fusarium/genética , Fusarium/metabolismo , Fusarium/fisiologia , Regulação Bacteriana da Expressão Gênica , Doenças das Plantas/microbiologia , Triticum/microbiologiaRESUMO
Cyclo (Phe-Pro) (cFP), a cyclic dipeptide with notable antifungal, antibacterial, and antiviral properties, shows great promise for biological control of plant diseases. Produced as a byproduct by non-ribosomal peptide synthetases (NRPS), the regulatory mechanism of cFP biosynthesis remains unclear. In a screening test of 997 Tn5 mutants of Burkholderia seminalis strain R456, we identified eight mutants with enhanced antagonistic effects against Fusarium graminearum (Fg). Among these, mutant 88's culture filtrate contained cFP, confirmed through HPLC and LC-MS, which actively inhibited Fg. The gene disrupted in mutant 88 is part of the Dct transport system (Dct-A, -B, -D), responsible for C4-dicarboxylate transport. Knockout mutants of Dct genes exhibited higher cFP levels than the wild type, whereas complementary strains showed no significant difference. Additionally, the presence of exogenous C4-dicarboxylates reduced cFP production in wild type R456, indicating that these substrates negatively regulate cFP synthesis. Given that cFP synthesis is related to NRPS, we previously identified an NRPS cluster in R456, horizontally transferred from algae. Specifically, knocking out gene 2061 within this NRPS cluster significantly reduced cFP production. A Fur box binding site was predicted upstream of gene 2061, and yeast one-hybrid assays confirmed Fur protein binding, which increased with additional C4-dicarboxylates. Knockout of the Fur gene led to up-regulation of gene 2061 and increased cFP production, suggesting that C4-dicarboxylates suppress cFP synthesis by enhancing Fur-mediated repression of gene 2061.
Assuntos
Burkholderia , Burkholderia/metabolismo , Burkholderia/genética , Fusarium/metabolismo , Fusarium/genética , Fusarium/efeitos dos fármacos , Peptídeos Cíclicos/biossíntese , Peptídeo Sintases/genética , Peptídeo Sintases/metabolismo , Ácidos Dicarboxílicos/metabolismo , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genéticaRESUMO
The present study revealed the consequences of the interaction of a widely used bioinsecticide and endophyte Metarhizium anisopliae with the hazardous mycotoxin zearalenone (ZEN) as a pure substance and with ZEN as a native component of a crude Fusarium extract. In the environment, microorganisms encounter a mixture of metabolites secreted by other organisms living in the same area, not single substances. The obtained results suggest that M. anisopliae, exposed to a variety of active substances produced by Fusarium graminearum, is able to eliminate ZEN. Within 14 days, M. anisopliae biotransformed 90.8% and 85.8% of ZEN as a pure substance and ZEN as a native component of the F. graminearum extract from Rice Medium (E-Fg-RM), respectively, through reduction predominantly to α-epimers of zearalenols and zearalanols, considered more estrogenic than ZEN, which can raise concerns. Compared to pure ZEN, E-Fg-RM significantly affected the production of Metarhizium secondary metabolites by increasing the destruxins amount by approximately 20-25% and reducing the swainsonine content by 96.2%. All these findings provide a possible picture of the interaction of M. anisopliae with ZEN in the wild, mainly as a result of the use of crude extract from Fusarium, which contained a mixture of different metabolites.
Assuntos
Endófitos , Fusarium , Metarhizium , Zearalenona , Fusarium/metabolismo , Zearalenona/metabolismo , Metarhizium/metabolismo , Endófitos/metabolismo , Micotoxinas/metabolismoRESUMO
Rice panicle blight (RPB) caused by various Fusarium spp. is an emerging disease in the major rice-growing regions of China. Epidemics of this disease cause significant yield loss and reduce grain quality by contaminating panicles with different Fusarium toxins. However, there is currently no registered fungicide for the control of RPB in China. The 14α-demethylation inhibitor (DMI) fungicide metconazole has been shown to be effective against several Fusarium spp. that cause wheat head blight, wheat crown rot and maize ear rot. In this study, we investigated the specific activity of metconazole against six Fusarium spp. that cause RPB. Metconazole significantly inhibited mycelial growth, conidium formation, germination, germ tube elongation and major toxin production in Fusarium strains collected from major rice-growing regions in China, as well as disrupting cell membrane function by inhibiting ergosterol biosynthesis. Greenhouse experiments indicated a significant reduction in blight occurrence and toxin accumulation in rice panicles treated with metconazole. Overall, our study demonstrated the potential of metconazole for managing RPB and toxin contamination, as well as providing insight into its bioactivities and modes of action of metconazole against distinct Fusarium spp.
Assuntos
Fungicidas Industriais , Fusarium , Oryza , Doenças das Plantas , Fusarium/efeitos dos fármacos , Fusarium/metabolismo , Oryza/microbiologia , Fungicidas Industriais/farmacologia , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Micotoxinas/biossíntese , Triazóis/farmacologia , Tricotecenos/metabolismoRESUMO
Chemical compounds that affect microbial interactions have attracted wide interest. In this study, Streptomyces griseus showed enhanced growth when cocultured with the rice blast fungus Pyricularia oryzae on potato dextrose agar (PDA) medium. An improvement in S. griseus growth was observed before contact with P. oryzae, and no growth-promoting effect was observed when the growth medium between the two microorganisms was separated. These results suggested that the chemicals produced by P. oryzae diffused through the medium and were not volatile. A PDA plate supplemented with phenol red showed that the pH of the area surrounding P. oryzae increased. The area with increased pH promoted S. griseus growth, suggesting that the alkaline compounds produced by P. oryzae were involved in this growth stimulation. In contrast, coculture with the soilborne plant pathogen Fusarium oxysporum and entomopathogenic fungus Cordyceps tenuipes did not promote S. griseus growth. Furthermore, DL-α-Difluoromethylornithine, a polyamine biosynthesis inhibitor, prevented the increase in pH and growth promotion of S. griseus by P. oryzae. These results indicated that P. oryzae increased pH by producing a polyamine.
Assuntos
Meios de Cultura , Fusarium , Streptomyces griseus , Streptomyces griseus/crescimento & desenvolvimento , Streptomyces griseus/metabolismo , Concentração de Íons de Hidrogênio , Meios de Cultura/química , Meios de Cultura/metabolismo , Fusarium/crescimento & desenvolvimento , Fusarium/efeitos dos fármacos , Fusarium/metabolismo , Interações Microbianas , Técnicas de Cocultura , Oryza/microbiologia , Oryza/crescimento & desenvolvimento , Planococáceas/crescimento & desenvolvimento , Planococáceas/metabolismo , Planococáceas/genética , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , AscomicetosRESUMO
Known mycotoxins have been investigated for years. They have been included in legislation and are meticulously controlled in most cereals, cereal-related products, and raw materials of animal origin. However, there are still mycotoxins that need to be addressed by regulations and subsequently are not monitored but can still occur in relatively high concentrations. This research aimed to assess the occurrence of common Fusarium mycotoxins in hulled barley. Samples of hulled barley were treated in the field with two protective treatments, alongside a control sample sans treatment. Furthermore, we aimed to assess the occurrence of Alternaria mycotoxins in the chosen samples. The results have shown that Fusarium mycotoxins were mostly determined by climatic conditions (no mycotoxins in 2020, except siccanol). Most interesting was the appearance of infectopyron, an Alternaria toxin that was detected in all samples in 2019 and in the majority of samples in 2020. The highest concentration was detected in 2019 in hulled barley with 536 µg/kg, while in 2020, the highest concentration of this mycotoxin reached 350 µg/kg. These findings depict the need for further research on food safety regarding mycotoxins, and the need for additional changes in legislation. This investigation shows that fungicide application in rainy years cannot efficiently suppress mycotoxin production. Additionally, even in dry years, some of the mycotoxins not involved in legislation, such as infectopyron and siccanol, do not respond to the application of fungicides.
Assuntos
Alternaria , Fusarium , Hordeum , Micotoxinas , Hordeum/metabolismo , Fusarium/metabolismo , Alternaria/metabolismo , Micotoxinas/análise , Micotoxinas/metabolismo , Contaminação de Alimentos/análise , Grão Comestível/metabolismo , Grão Comestível/microbiologia , Grão Comestível/químicaRESUMO
All major ear rots (F. graminearum, F. verticillioides, and Aspergillus flavus) and their toxins are present in maize of preharvest origin in Hungary. Resistance can be an important tool in reducing the infection and toxin contamination from these rots in maize. Previous results identified resistance differences in maize hybrids that were suitable for use in evaluating their risk from toxigenic fungi and their toxins. During the tests, two methodical improvements were achieved: the use of three isolates of the fungus secured and a more precise estimation of resistance to ear rots and their resistance to toxin accumulation or overproduction. The improvement in sampling and the tests of subsamples made the evaluation for the statistics much more exact. This way, we were able to reduce the Within value, providing a statistically more reliable method of evaluation. Earlier data had confirmed that toxin contamination could not be predicted well from visual ear rot severity data. Contradictory results for hybrid ranking were often identified between isolates. The resistance to disease and toxin contamination is not generally valid. The new suggested methodology compares the performance of hybrids in a large number of epidemic situations to identify adaptable hybrids that can respond to diverse conditions; therefore, the stability of resistance and toxin response is decisive information to evaluate risk analyses. The increased number of disease toxin data allowed for lower LSD 5% values for toxins, a much finer analysis of toxin overproduction and underproduction, and a wider database for stability analyses. This way, we obtained important additional separated information about resistance to accumulation of toxins and about maize resistance to these pathogens that is suitable to provide much more reliable testing than was possible until now. Globally, about 50-100 million metric tons can be saved by excluding susceptible hybrids from commercial production.
Assuntos
Aspergillus flavus , Fusarium , Micotoxinas , Doenças das Plantas , Zea mays , Zea mays/microbiologia , Aspergillus flavus/metabolismo , Doenças das Plantas/microbiologia , Micotoxinas/análise , Fusarium/metabolismo , Hungria , Resistência à DoençaRESUMO
Fusarium graminearum (Fg) is the primary causal agent of Fusarium head blight (FHB) in wheat, barley, and other small grains in North America and worldwide. FHB results in yield reduction and contaminates grain with mycotoxins that pose threats to human and livestock health. Three genetically distinct North American (NA) populations of Fg have been characterized, which are generally associated with differences in their predominant trichothecene chemotype: NA1/15-acetyl-deoxynivalenol (15-ADON), NA2/3-acetyl-deoxynivalenol (3-ADON), and NA3/3α-acetoxy, 7,15-dihydroxy-12,13-epoxytrichothec-9-ene (NX-2). Recent studies found that the NA3 population had significantly less spread on point-inoculated wheat spikes than the NA1 and NA2 populations, and NX toxins are important for Fg spread and initial infection in wheat. In this follow-up study, to compare the effect of the three populations on initial infection and mycotoxin production on different hosts, we dip-inoculated spikes of the moderately resistant wheat cultivar Alsen and the susceptible barley cultivar Voyager using five strains from each population to evaluate disease, trichothecene mycotoxin accumulation, and trichothecene production per unit of fungal biomass. In dip-inoculated wheat spikes, the NA3 population produced significantly more trichothecene per unit of fungal biomass and accumulated higher levels of trichothecene per plant biomass than the NA1 and NA2 populations, regardless of the disease levels caused by the three populations. In contrast to its critical role during wheat infection, NX toxins had no effect on barley infection. In dip-inoculated barley, the NA1 population was more infectious and caused more severe FHB symptoms than the NA2 and NA3 populations; however, the NA3 population produced significantly higher toxin per unit of fungal biomass in infected barley tissues than the NA1 population. This study provides critical information on the emerging NA3 population, which produces high levels of NX toxin and poses a potential food safety concern.
Assuntos
Fusarium , Hordeum , Doenças das Plantas , Tricotecenos , Triticum , Fusarium/metabolismo , Hordeum/microbiologia , Triticum/microbiologia , Doenças das Plantas/microbiologia , Tricotecenos/metabolismo , Micotoxinas/metabolismo , Contaminação de Alimentos/análiseRESUMO
Fungal phytopathogens represent a large and economically significant challenge to food production worldwide. Thus, the application of biocontrol agents can be an alternative. In the present study, we carried out biological, metabolomic, and genetic analyses of three endophytic isolates from nodules of Chamaecytisus albus, classified as Pseudomonas chlororaphis acting as antifungal agents. The efficiency of production of their diffusible and volatile antifungal compounds (VOCs) was verified in antagonistic assays with the use of soil-borne phytopathogens: B. cinerea, F. oxysporum, and S. sclerotiorum. Diffusible metabolites were identified using chromatographic and spectrometric analyses (HPTLC, GC-MS, and LC-MS/MS). The phzF, phzO, and prnC genes in the genomes of bacterial strains were confirmed by PCR. In turn, the plant growth promotion (PGP) properties (production of HCN, auxins, siderophores, and hydrolytic enzymes, phosphate solubilization) of pseudomonads were bioassayed. The data analysis showed that all tested strains have broad-range antifungal activity with varying degrees of antagonism. The most abundant bioactive compounds were phenazine derivatives: phenazine-1-carboxylic acid (PCA), 2-hydroxy-phenazine, and diketopiperazine derivatives as well as ortho-dialkyl-aromatic acids, pyrrolnitrin, siderophores, and HCN. The results indicate that the tested P. chlororaphis isolates exhibit characteristics of biocontrol organisms; therefore, they have potential to be used in sustainable agriculture and as commercial postharvest fungicides to be used in fruits and vegetables.
Assuntos
Antifúngicos , Pseudomonas chlororaphis , Antifúngicos/farmacologia , Antifúngicos/química , Pseudomonas chlororaphis/metabolismo , Ascomicetos/metabolismo , Fusarium/efeitos dos fármacos , Fusarium/metabolismo , Botrytis/efeitos dos fármacos , Endófitos/metabolismo , Metabolômica/métodos , Compostos Orgânicos Voláteis/farmacologia , Compostos Orgânicos Voláteis/metabolismo , Compostos Orgânicos Voláteis/química , Fenazinas/metabolismo , Fenazinas/farmacologia , Fenazinas/química , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controleRESUMO
Fungal secondary metabolites play a highly significant role in crop protection, which is related to their antifungal activity against agriculturally important phytopathogens. In fact, plant diseases caused by fungi including species belonging to the genera of Alternaria, Botrytis, and Fusarium have become increasingly serious affecting crop yield and quality. Hence, there is increasing awareness by the scientific community of the importance of exploiting fungal products for finding new compounds able to inhibit phytopathogens. In this study several drimane-type sesquiterpenes have been detected for the first time as products of Aspergillus xerophilus by GC-MS analysis of the organic extracts obtained from the mycelia and culture filtrates of the fungus grown on two different substrates. Seven pure drimane-type sesquiterpenes were also isolated and identified by spectroscopic methods. The inhibitory effects of the pure compounds have been investigated against three phytopathogenic fungi of agrarian crops (i.e., Botrytis cinerea, Alternaria alternata, and Fusarium oxysporum f. sp. pisi). Among the drimane-type sesquiterpenes isolated in this study, 9,11-dihydroxy-6-oxodrim-7-ene is the most active against the three phytopathogens. Our findings also reveal the high sensitivity of A. alternata to the isolated compounds. These results pave the way for future applications in agriculture of both A. xerophilus and its metabolites.
Assuntos
Alternaria , Aspergillus , Botrytis , Fungicidas Industriais , Fusarium , Doenças das Plantas , Metabolismo Secundário , Aspergillus/metabolismo , Aspergillus/efeitos dos fármacos , Aspergillus/química , Alternaria/efeitos dos fármacos , Alternaria/metabolismo , Alternaria/química , Fusarium/efeitos dos fármacos , Fusarium/metabolismo , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Botrytis/efeitos dos fármacos , Fungicidas Industriais/farmacologia , Fungicidas Industriais/química , Fungicidas Industriais/metabolismo , Produtos Agrícolas/microbiologia , Cromatografia Gasosa-Espectrometria de Massas , Sesquiterpenos/farmacologia , Sesquiterpenos/metabolismo , Sesquiterpenos/químicaRESUMO
Flax (Linum usitatissimum L.) is an important crop plant with pharmaceutical significance. It is described in pharmacopoeias (the United States Pharmacopeia and the European Pharmacopoeia), which confirms that it (especially the seeds) is a valuable medicinal product. Similar to flax seeds, which accumulate bioactive compounds, flax in vitro cultures are also a rich source of flavonoids, phenolics, lignans and neolignans. In the present study, flax suspension cultures after treatment of the non-pathogenic Fusarium oxysporum strain Fo47 were established and analyzed. The study examined the suitability of Fo47 as an elicitor in flax suspension cultures and provided interesting data on the impact of these endophytic fungi on plant metabolism and physiology. Two flax cultivars (Bukoz and Nike) and two compositions of media for flax callus liquid cultures were tested. Biochemical analysis revealed enhanced levels of secondary metabolites (total flavonoid and total phenolic content) and photosynthetically active pigments in the flax callus cultures after treatment with the non-pathogenic fungal strain F. oxysporum Fo47 when compared to control, untreated cultures. In cultures with the selected, optimized conditions, FTIR analysis was performed and revealed changes in the structural properties of cell wall polymers after elicitation of cultures with F. oxysporum Fo47. The plant cell wall polymers were more strongly bound, and the crystallinity index (Icr) of cellulose was higher than in control, untreated samples. However, lignin and pectin levels were lower in the flax callus liquid cultures treated with the non-pathogenic strain of Fusarium when compared to the untreated control. The potential application of the non-pathogenic strain of F. oxysporum for enhancing the synthesis of desired secondary metabolites in plant tissue cultures is discussed.
Assuntos
Linho , Fusarium , Fusarium/metabolismo , Linho/microbiologia , Linho/metabolismo , Flavonoides/metabolismo , Fenóis/metabolismo , Parede Celular/metabolismo , Parede Celular/química , Sementes/microbiologia , Sementes/metabolismoRESUMO
Anaplerosis refers to enzymatic reactions or pathways replenishing metabolic intermediates in the tricarboxylic acid (TCA) cycle. Pyruvate carboxylase (PYC) plays an important anaplerotic role by catalyzing pyruvate carboxylation, forming oxaloacetate. Although PYC orthologs are well conserved in prokaryotes and eukaryotes, their pathobiological functions in filamentous pathogenic fungi have yet to be fully understood. Here, we delve into the molecular functions of the ortholog gene PYC1 in Fusarium graminearum and F. oxysporum, prominent fungal plant pathogens with distinct pathosystems, demonstrating variations in carbon metabolism for pathogenesis. Surprisingly, the PYC1 deletion mutant of F. oxysporum exhibited pleiotropic defects in hyphal growth, conidiation, and virulence, unlike F. graminearum, where PYC1 deletion did not significantly impact virulence. To further explore the species-specific effects of PYC1 deletion on pathogenicity, we conducted comprehensive metabolic profiling. Despite shared metabolic changes, distinct reprogramming in central carbon and nitrogen metabolism was identified. Specifically, alpha-ketoglutarate, a key link between the TCA cycle and amino acid metabolism, showed significant down-regulation exclusively in the PYC1 deletion mutant of F. oxysporum. The metabolic response associated with pathogenicity was notably characterized by S-methyl-5-thioadenosine and S-adenosyl-L-methionine. This research sheds light on how PYC1-mediated anaplerosis affects fungal metabolism and reveals species-specific variations, exemplified in F. graminearum and F. oxysporum.
Assuntos
Proteínas Fúngicas , Fusarium , Doenças das Plantas , Fusarium/patogenicidade , Fusarium/genética , Fusarium/metabolismo , Doenças das Plantas/microbiologia , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Virulência , Ciclo do Ácido Cítrico , Ácido Oxaloacético/metabolismo , Piruvato Carboxilase/metabolismo , Piruvato Carboxilase/genéticaRESUMO
BACKGROUND: Fusarium wilt is a devastating soil-borne fungal disease of tomato across the world. Conventional method of disease prevention including usage of common pesticides and methods like soil solarisation are usually ineffective in the treatment of this disease. Therefore, there is an urgent need to identify virulence related genes in the pathogen which can be targeted for fungicide development. RESULTS: Pathogenicity testing and phylogenetic classification of the pathogen used in this study confirmed it as Fusarium oxysporum f. sp. lycopersici (Fol) strain. A recent discovery indicates that EF1α, a protein with conserved structural similarity across several fungal genera, has a role in the pathogenicity of Magnaporthe oryzae, the rice blast fungus. Therefore, in this study we have done structural and functional classification of EF1α to understand its role in pathogenicity of Fol. The protein model of Fol EF1α was created using the template crystal structure of the yeast elongation factor complex EEF1A:EEF1BA which showed maximum similarity with the target protein. Using the STRING online database, the interactive information among the hub genes of EF1α was identified and the protein-protein interaction network was recognized using the Cytoscape software. On combining the results of functional analysis, MCODE, CytoNCA and CytoHubba 4 hub genes including Fol EF1α were selected for further investigation. The three interactors of Fol EF1α showed maximum similarity with homologous proteins found in Neurospora crassa complexed with the known fungicide, cycloheximide. Through the sequence similarity and PDB database analysis, homologs of Fol EF1α were found: EEF1A:EEF1BA in complex with GDPNP in yeast and EF1α in complex with GDP in Sulfolobus solfataricus. The STITCH database analysis suggested that EF1α and its other interacting partners interact with guanosine diphosphate (GDPNP) and guanosine triphosphate (GTP). CONCLUSIONS: Our study offers a framework for recognition of several hub genes network in Fusarium wilt that can be used as novel targets for fungicide development. The involvement of EF1α in nucleocytoplasmic transport pathway suggests that it plays role in GTP binding and thus apart from its use as a biomarker, it may be further exploited as an effective target for fungicide development. Since, the three other proteins that were found to be tightly associated Fol EF1α have shown maximum similarity with homologous proteins of Neurospora crassa that form complex with fungicide- Cycloheximide. Therefore, we suggest that cycloheximide can also be used against Fusarium wilt disease in tomato. The active site cavity of Fol EF1α can also be determined for computational screening of fungicides using the homologous proteins observed in yeast and Sulfolobus solfataricus. On this basis, we also suggest that the other closely associated genes that have been identified through STITCH analysis, they can also be targeted for fungicide development.
Assuntos
Proteínas Fúngicas , Fusarium , Fator 1 de Elongação de Peptídeos , Filogenia , Doenças das Plantas , Fusarium/genética , Fusarium/metabolismo , Fusarium/patogenicidade , Fator 1 de Elongação de Peptídeos/genética , Doenças das Plantas/microbiologia , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Solanum lycopersicum/microbiologia , Mapas de Interação de Proteínas , Reação em Cadeia da Polimerase , Virulência/genética , Modelos MolecularesRESUMO
Cello-oligosaccharides (COS) become a new type of functional oligosaccharides. COS transglycosylation reactions were studied to enhance COS yield production. Seeking the ability of the free form of Fusarium solani ß-glucosidase (FBgl1) to synthesize COS under low substrate concentrations, we found out that this biocatalyst initiates this reaction with only 1 g/L of cellobiose, giving rise to the formation of cellotriose. Cellotriose and cellopentaose were detected in biphasic conditions with an immobilized FBgl1 and when increased to 50 g/L of cellobiose as a starter concentration. After the biocatalyst recycling process, the trans-glycosylation yield of COS was maintained after 5 cycles, and the COS concentration was 6.70 ± 0.35 g/L. The crude COS contained 20.15 ± 0.25 g/L glucose, 23.15 ± 0.22 g/L non-reacting substrate cellobiose, 5.25 ± 0.53 g/L, cellotriose and 1.49 ± 0.32 g/L cellopentaose. A bioprocess was developed for cellotriose enrichment, using whole Bacillus velezensis cells as a microbial purification tool. This bacteria consumed glucose, unreacted cellobiose, and cellopentaose while preserving cellotriose in the fermented medium. This study provides an excellent enzyme candidate for industrial COS production and is also the first study on the single-step COS enrichment process.
Assuntos
Bacillus , Celobiose , Fusarium , Oligossacarídeos , beta-Glucosidase , Fusarium/enzimologia , Fusarium/metabolismo , Fusarium/genética , beta-Glucosidase/metabolismo , Oligossacarídeos/metabolismo , Celobiose/metabolismo , Bacillus/enzimologia , Bacillus/metabolismo , Bacillus/genética , Prebióticos , Glicosilação , Glucose/metabolismoRESUMO
Fusarium graminearum, the primary pathogen responsible for wheat Fusarium head blight, can induce pulmonary damage through its spores. However, the detailed mechanism by which these spores cause intestinal injury is not yet fully understood. This study aimed to investigate the impact of exposure to fungal spores on the intestinal microbiota using a mice model that mimics the effects of fusarium graminearum spores on the gut microbiota and its metabolic profile. The study utilized 16S rRNA sequencing and metabolomics methodologies to analyze the contents of the cecum and feces in mice. The results showed that exposure to fungal spores led to significant changes in the composition of the intestinal microbiota in mice, characterized by an increase in Akkermansia and Staphylococcus populations. A non-targeted metabolomics analysis identified 316 metabolites associated with various metabolic pathways, particularly galactose metabolism. Pre-exposure to antibiotics before fungal spore exposure resulted in a decrease in the metabolic capacity of the intestinal microbiota in mice. This research demonstrates that fusarium graminearum spores can disrupt the intestinal microbiota and metabolome via the lung-gut axis. These findings provide valuable insights into the intestinal damage caused by fungal spores and offer important support for the development of therapeutic strategies for intestinal diseases.
Assuntos
Fusarium , Microbioma Gastrointestinal , Pulmão , Metaboloma , Esporos Fúngicos , Animais , Fusarium/metabolismo , Esporos Fúngicos/metabolismo , Pulmão/microbiologia , Pulmão/metabolismo , Camundongos , RNA Ribossômico 16S/genética , Masculino , Fezes/microbiologia , Metabolômica , Antibacterianos/farmacologiaRESUMO
Fungal infections are among the most common diseases of crop plants. Various species of the Fusarium spp. are naturally prevalent and globally cause the qualitative and quantitative losses of farming commodities, mainly cereals, fruits, and vegetables. In addition, Fusarium spp. can synthesize toxic secondary metabolites-mycotoxins under high temperature and humidity conditions. Among the strategies against Fusarium spp. incidence and mycotoxins biosynthesis, the application of biological control, specifically natural plant extracts, has proved to be one of the solutions as an alternative to chemical treatments. Notably, rowanberries taken from Sorbus aucuparia are a rich source of phytochemicals, such as vitamins, carotenoids, flavonoids, and phenolic acids, as well as minerals, including iron, potassium, and magnesium, making them promising candidates for biological control strategies. The study aimed to investigate the effect of rowanberry extracts obtained by supercritical fluid extraction (SFE) under different conditions on the growth of Fusarium (F. culmorum and F. proliferatum) and mycotoxin biosynthesis. The results showed that various extracts had different effects on Fusarium growth as well as ergosterol content and mycotoxin biosynthesis. These findings suggest that rowanberry extracts obtained by the SFE method could be a natural alternative to synthetic fungicides for eradicating Fusarium pathogens in crops, particularly cereal grains. However, more research is necessary to evaluate their efficacy against other Fusarium species and in vivo applications.
Assuntos
Fusarium , Micotoxinas , Extratos Vegetais , Sorbus , Fusarium/efeitos dos fármacos , Fusarium/metabolismo , Fusarium/crescimento & desenvolvimento , Micotoxinas/biossíntese , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Sorbus/química , Ergosterol/biossínteseRESUMO
The presence of different mycotoxins in 232 tuber samples exhibiting dry rot symptoms and their associated Fusarium strains from two production sites in Algeria was investigated. LC-MS/MS was used to simultaneously detect and quantify 14 mycotoxins, including trichothecenes and non-trichothecenes. A total of 49 tubers were contaminated with at least one mycotoxins, including T-2, HT-2, Diacetoxyscirpenol (DAS), 15-acetoxyscirpenol (15-AS) and Beauvericin (BEA). Positive samples from the Bouira region had a significantly higher level of toxin contamination compared to Ain Defla (56.34% and 5.59%, respectively). A total of 283 Fusarium strains were isolated: 155 from Bouira and 128 from Ain Defla. These strains were evaluated for their ability to produce the targeted mycotoxins. The results showed that 61.29% and 53.9% of strains originate from Bouira and Ain Defla regions were able to produce Nivalenol, Fusarenone-X, DAS, 15-AS, Neosolaniol, BEA and Zearalenone. The phylogenetic analysis of the conserved ribosomal internal transcribed spacer (ITS) sequences of 29 Fusarium strains, representative of the recorded mycotoxins profiles, was distributed into 5 Fusarium species complexes (SC): F. incarnatum-equiseti SC (FIESC), F. sambucinum SC (FSAMSC), F. oxysporum SC (FOSC), F. tricinctum SC (FTSC) and F. redolens SC (FRSC). This is the first study determining multiple occurrences of mycotoxins contamination associated to Fusarium dry rot of potato in Algeria and highlights fungal potential for producing trichothecene and non-trichothecens mycotoxins.
Assuntos
Fusarium , Micotoxinas , Doenças das Plantas , Tubérculos , Solanum tuberosum , Fusarium/metabolismo , Fusarium/genética , Fusarium/classificação , Fusarium/isolamento & purificação , Fusarium/química , Argélia , Micotoxinas/metabolismo , Micotoxinas/análise , Solanum tuberosum/microbiologia , Doenças das Plantas/microbiologia , Tubérculos/microbiologia , Espectrometria de Massas em Tandem , Cromatografia Líquida , FilogeniaRESUMO
Zearalenone, a prominent mycotoxin produced by Fusarium spp., ubiquitously contaminates cereal grains and animal feedstuffs. The thermal stability of zearalenone creates serious obstacles for traditional removal methods, which may introduce new safety issues, or reducing nutritional quality. In contrast, biological technologies provide appealing benefits such as easy to apply and effective, with low toxicity byproducts. Thus, this review aims to describe the occurrence of zearalenone in cereals and cereal-based feedstuffs in the recent 5 years, outline the rules and regulations regarding zearalenone in the major countries, and discuss the recent developments of biological methods for controlling zearalenone in cereals and cereal-based feedstuffs. In addition, this article also reviews the application and the development trend of biological strategies for removal zearalenone in cereals and cereal-based feedstuffs.