RESUMO
Fusarium oxysporum is a cross-kingdom pathogen that infects humans, animals, and plants. The primary concern regarding this genus revolves around its resistance profile to multiple classes of antifungals, particularly azoles. However, the resistance mechanism employed by Fusarium spp. is not fully understood, thus necessitating further studies to enhance our understanding and to guide future research towards identifying new drug targets. Here, we employed an untargeted proteomic approach to assess the differentially expressed proteins in a soil isolate of Fusarium oxysporum URM7401 cultivated in the presence of amphotericin B and fluconazole. In response to antifungals, URM7401 activated diverse interconnected pathways, such as proteins involved in oxidative stress response, proteolysis, and lipid metabolism. Efflux proteins, antioxidative enzymes and M35 metallopeptidase were highly expressed under amphotericin B exposure. Antioxidant proteins acting on toxic lipids, along with proteins involved in lipid metabolism, were expressed during fluconazole exposure. In summary, this work describes the protein profile of a resistant Fusarium oxysporum soil isolate exposed to medical antifungals, paving the way for further targeted research and discovering new drug targets.
Assuntos
Anfotericina B , Antifúngicos , Fluconazol , Proteínas Fúngicas , Fusarium , Proteômica , Microbiologia do Solo , Fusarium/efeitos dos fármacos , Fusarium/metabolismo , Fusarium/genética , Antifúngicos/farmacologia , Antifúngicos/metabolismo , Fluconazol/farmacologia , Anfotericina B/farmacologia , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Farmacorresistência Fúngica , Testes de Sensibilidade Microbiana , Proteoma/análiseRESUMO
Crops contamination with aflatoxins (AFs) and zearalenone (ZEA) threaten human and animal health; these mycotoxins are produced by several species of Aspergillus and Fusarium. The objective was to evaluate under field conditions the influence of the wet season on the dissemination of AF- and ZEA-producing fungi via houseflies collected from dairy farms. Ten dairy farms distributed in the semi-arid Central Mexican Plateau were selected. Flies were collected in wet and dry seasons at seven points on each farm using entomological traps. Fungi were isolated from fly carcasses via direct seeding with serial dilutions and wet chamber methods. The production of AFs and ZEA from pure isolates was quantified using indirect competitive ELISA. A total of 693 Aspergillus spp. and 1274 Fusarium spp. isolates were obtained, of which 58.6% produced AFs and 50.0% produced ZEA (491 ± 122; 2521 ± 1295 µg/kg). Houseflies and both fungal genera were invariably present, but compared to the dry season, there was a higher abundance of flies as well as AF- and ZEA-producing fungi in the wet season (p < 0.001; 45.3/231 flies/trap; 8.6/29.6% contaminated flies). These results suggest that rainy-weather conditions on dairy farms increase the spread of AF- and ZEA-producing Aspergillus spp. and Fusarium spp. through houseflies and the incorporation of their mycotoxins into the food chain.
Assuntos
Aflatoxinas , Aspergillus , Indústria de Laticínios , Fusarium , Moscas Domésticas , Estações do Ano , Zearalenona , Animais , Fusarium/metabolismo , México , Aspergillus/metabolismo , Aspergillus/isolamento & purificação , Aflatoxinas/biossíntese , Moscas Domésticas/microbiologia , Contaminação de Alimentos/análise , FazendasRESUMO
Fusarium verticillioides causes significant decrease in corn yield and quality, and produces fumonisins, which represent a serious risk to human and animal health. Bacillus species can be an effective and environmentally friendly alternative for F. verticillioides biological control. In this study, some properties of cell-free supernatants (CFSs) of two Bacillus spp. identified as Bacillus subtilis (NT1, NT2) as well as the antifungal effect against F. verticillioides 97L were evaluated. B. subtilis NT1 and NT2 were isolated from commercially available fermented whole soybeans (Natto). Antifungal activity was observed in both CFSs of B. subtilis isolates (50-59 mm) obtained by co-culture suggesting that antifungal compound production depends on interaction between bacteria and fungi. Cell-free supernatants from the two B. subtilis isolates inhibited mycelial growth (77%-94%) and conidial germination (22%-74%) of F. verticillioides 97L. In addition, CFSs caused significant morphological changes such as distorted and collapsed hyphae with wrinkled surfaces and the presence of a large amount of extracellular material compared to the control without CFSs. Both B. subtilis isolates (NT1 and NT2) produced extracellular proteases, biosurfactants and polar low molecular weight compounds that probably act synergistically and may contribute to the antifungal activity. Antifungal compounds showed heat and pH stability and resistance to proteolytic enzymes. Furthermore, antifungal compounds showed high polarity, high affinity to water and a molecular weight less than 10 kDa. These results indicated that the two B. subtilis (NT1 and NT2) have potential as biocontrol agents for F. verticillioides.
Assuntos
Antifúngicos , Bacillus subtilis , Fusarium , Bacillus subtilis/metabolismo , Fusarium/efeitos dos fármacos , Fusarium/crescimento & desenvolvimento , Fusarium/metabolismo , Antifúngicos/farmacologia , Antifúngicos/metabolismo , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Glycine max/microbiologia , Zea mays/microbiologia , Esporos Fúngicos/crescimento & desenvolvimento , Esporos Fúngicos/efeitos dos fármacos , AntibioseRESUMO
IMPORTANCE: Fusaric acid (FA) is an important virulence factor produced by several Fusarium species. These fungi are responsible for wilt and rot diseases in a diverse range of crops. FA is toxic for animals, humans and soil-borne microorganisms. This mycotoxin reduces the survival and competition abilities of bacterial species able to antagonize Fusarium spp., due to its negative effects on viability and the production of antibiotics effective against these fungi. FA biodegradation is not a common characteristic among bacteria, and the determinants of FA catabolism have not been identified so far in any microorganism. In this study, we identified genes, enzymes, and metabolic pathways involved in the degradation of FA in the soil bacterium Burkholderia ambifaria T16. Our results provide insights into the catabolism of a pyridine-derivative involved in plant pathogenesis by a rhizosphere bacterium.
Assuntos
Complexo Burkholderia cepacia , Burkholderia , Fusarium , Micotoxinas , Animais , Humanos , Micotoxinas/metabolismo , Ácido Fusárico/metabolismo , Burkholderia/metabolismo , Complexo Burkholderia cepacia/metabolismo , Fungos/metabolismo , Solo , Fusarium/metabolismo , Doenças das Plantas/microbiologiaRESUMO
Fusarium oxysporum is an entomopathogenic fungus, and it has anti-biological activity against arthropods. Ticks are blood sucking arthropods which are responsible for transmitting different diseases in humans and animals. The use of chemical insecticides against ticks is not eco-friendly option and results in the development of acaricide resistance. Previously, we had cultured a local isolate of Fusarium oxysporum from soil samples which were identified through microscopy and confirmed through molecular technique. In our previous experiments, we have prepared Silver nanoparticles (AgNP) at pH 7 and they had been characterized through X-Ray Diffraction (XRD), UV-visible and zeta-potential. In our current study, the AgNP were prepared at different pH conditions and characterized through Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). The protein molecules of F. oxysporum were charged with Ag ions. F. oxysporum NP were observed to enhance anti-biological activity by killing Rhipicephalus microplus and they caused 100% mortality at pH 4 and pH 5 in 24 h in anti-tick biological assay. Our study is the first report to do biological assay against Rhipicehalus ticks by using Fusarium AgNP at acidic pH. Biological control using entomopathogenic fungi can be the best alternative of the chemical method to control the tick population.
Assuntos
Fusarium , Nanopartículas Metálicas , Rhipicephalus , Animais , Humanos , Fusarium/metabolismo , Prata/química , Prata/metabolismo , Nanopartículas Metálicas/química , FungosRESUMO
Fructooligosaccharides (FOS) are fructose-based oligosaccharides employed as additives to improve the food's nutritional and technological properties. The rhizosphere of plants that accumulate fructopolysaccharides as inulin has been revealed as a source of filamentous fungi. These fungi can produce FOS either by inulin hydrolysis or by biosynthesis from sucrose, including unusual FOS with enhanced prebiotic properties. Here, we investigated the ability of Fusarium solani and Neocosmospora vasinfecta to produce FOS from different carbon sources. Fusarium solani and N. vasinfecta grew preferentially in inulin instead of sucrose, resulting in the FOS production as the result of endo-inulinase activities. N. vasinfecta was also able to produce the FOS 1-kestose and 6-kestose from sucrose, indicating transfructosylating activity, absent in F. solani. Moreover, the results showed how these carbon sources affected fungal cell wall composition and the expression of genes encoding for ß-1,3-glucan synthase and chitin synthase. Inulin and fructose promoted changes in fungal macroscopic characteristics partially explained by alterations in cell wall composition. However, these alterations were not directly correlated with the expression of genes related to cell wall synthesis. Altogether, the results pointed to the potential of both F. solani and N. vasinfecta to produce FOS at specific profiles.
Assuntos
Fusarium , Inulina , Inulina/metabolismo , Oligossacarídeos , Fusarium/genética , Fusarium/metabolismo , Frutose/metabolismo , Sacarose/metabolismo , CarbonoRESUMO
The influence of aw on DON and its acetyl derivatives biosynthesis by a strain of Fusarium graminearum s.s. (ITEM 4606) which produces DON, 3-ADON and 15-ADON was evaluated. Trichothecene production was studied on agar wheat 2% at 0.95 and 0.99 aw at different temperatures (10, 15, 20, 25 and 30 °C) and incubation times (7, 14, 21 and 28 days). Statistical analysis (ANOVA) showed that aw, temperature, incubation time and their interactions were significant on the production of DON, 3-ADON and 15-ADON (p < 0.0001). The pattern of toxin production was influenced by aw, showing differences for the three toxins. The maximum accumulation of DON occurred at 30 °C at 0.99 aw (14 d) and at 25 °C at 0.95 aw (7 and 21 d). The highest concentration of 3-ADON at 0.95 aw was observed at 25 °C and 7 days, and it was significantly higher than all the other values registered. At 0.99 aw, the maximum occurred at 30 °C and 21 days, but another significantly high accumulation was observed at 28 days at the same temperature. For 15-ADON, at 0.95 aw, the highest amount of toxin was accumulated at 10 °C, both at 7 and 28 days. At 0.99 aw, a maximum was observed at 10 °C and 7 days, significantly different from the values observed at the other conditions. The toxin accumulated at a higher concentration at 0.95 aw was 15-ADON (173.2 µg/g) and at 0.99 aw, 3-ADON (370.6 µg/g). A marked influence of aw on the maximum toxin accumulation with respect to temperature and time was observed for trichothecene production. This is an important fact to consider when designing predictive models to prevent toxin contamination, both in the field and during storage, especially in intermediate drying stages.
Assuntos
Fusarium , Tricotecenos , Água , Fusarium/genética , Fusarium/metabolismo , Genótipo , Tricotecenos/análise , Tricotecenos/metabolismoRESUMO
The production of beauvericin (BEA) by Fusarium oxysporum AB2 in liquid medium (SmF) was compared to that on solid medium (SSF) on inert support (polyurethane foam or PUF), using a previously optimised medium. The analysis included two different concentrations of the medium (1 × and 3 ×). Under SSF, the production of BEA (22.8 mg·L-1) was higher relative to SmF (0.8 mg·L-1). The production increased proportionally in the concentrated medium (3 ×) (65.3 mg·L-1); using the concentrated medium in SmF, the production of BEA was completely inhibited, although more biomass was produced. The peak of BEA production was reached on day 7 and remained stable until day 11; sustained production after several days has not been achieved in similar reports. The presence of BEA was corroborated by high-performance liquid chromatography (HPLC) and mass spectrometry. The BEA production profile is shown performing mixed cultures of Fusarium oxysporum AB2 and Epicoccum nigrum TORT using the same system, increasing the production of BEA up to 84.6 mg·L-1. We propose SSF using polyurethane foam (PUF) as a solid support as a new culture system for obtaining secondary metabolites such as BEA.
Assuntos
Depsipeptídeos , Fusarium , Técnicas de Cocultura , Fermentação , Fusarium/metabolismoRESUMO
This study aimed to evaluate the antimycotoxigenic effect of essential oils (EOs) obtained from four different aromatic plants on the production of deoxynivalenol (DON) and zearalenone (ZEA) by Fusarium graminearum. The EOs from ginger (GEO), turmeric (TEO), thyme (ThEO) and rosemary (REO) were obtained by hydrodistillation and identified by gas chromatography/mass spectrometry (GC/MS). The major compounds found were mostly monoterpenes and sesquiterpenes. The minimum inhibitory concentration (MIC) and minimum fungicide concentration (MFC) were 11.25, 364, 366 and 11,580 µg mL-1 for ThEO, GEO, REO and TEO, respectively. The results evidenced that the assessed EOs inhibited DON and partially ZEA production by F. graminearum. ThEO and GEO were the EOs with most potent antimycotoxigenic action for DON and ZEA, respectively. These EOs have shown promising results in vitro regarding inhibition of mycotoxin production and might be used in the future as substitutes for synthetic fungicides.
Assuntos
Antifúngicos/farmacologia , Fusarium/efeitos dos fármacos , Óleos Voláteis/farmacologia , Tricotecenos/metabolismo , Zearalenona/metabolismo , Antifúngicos/química , Curcuma/química , Fusarium/química , Fusarium/metabolismo , Zingiber officinale/química , Testes de Sensibilidade Microbiana , Óleos Voláteis/química , Rosmarinus/química , Thymus (Planta)/química , Tricotecenos/química , Zearalenona/químicaRESUMO
Dibutyl phthalate (DBP) is one of the most abundantly produced and used plasticizers and is incorporated into plastic to make it more flexible and malleable. DBP has been found to be an environmental contaminant and reported as an endocrine disruptor. Therefore, it is crucial to develop ecofriendly alternatives to eliminate phthalate pollution. In the present research, the growth of F. culmorum and F. oxysporum in the presence of DBP was studied in liquid fermentation. The esterase activity, specific growth rate, and growth and enzymatic yield parameters were determined in DBP-supplemented media (1,500 or 2,000 mg/L) and in control medium (lacking DBP). These results show that in general, for both Fusarium species, the highest esterase activities, specific growth rates, and yield parameters were observed in media supplemented with DBP. It was observed that 1,500 and 2,000 mg of DBP/L did not inhibit F. culmorum or F. oxysporum growth and that DBP induced esterase production in both fungi. These organisms have much to offer in the mitigation of environmental pollution caused by the endocrine disruptor DBP. This study reports, for the first time, esterase production during the degradation of high concentrations (i.e., 1,500 and 2,000 mg/L) of DBP by F. culmorum F. oxysporum.