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1.
Sci Total Environ ; 802: 149792, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34464790

RESUMO

The eco-sustainability of industrial processes relies on the proper exploitation of by-products and wastes. Recently, brewers' spent grain (BSG), the main by-product of brewing, was successfully recycled through vermicomposting to produce an organic soil conditioner. However, the pre-processing step there applied (oven-drying) resulted in high costs and the suppression of microbial species beneficial for soil fertility. To overcome these limitations, a low-input pre-processing step was here applied to better exploit BSG microbiota and to make BSG suitable for vermicomposting. During 51 days of pre-treatment, the bacterial and fungal communities of BSG were monitored by denaturing gradient gel electrophoresis (DGGE). Chemical (carbon, nitrogen, ammonium, nitrate content, dissolved organic carbon) and biochemical (dehydrogenase activity) parameters were also evaluated. Mature vermicompost obtained from pre-processed BSG was characterized considering its legal requirements (e.g., absence of pathogens and mycotoxins, lack of phytotoxicity on seeds), microbiota composition, and chemical properties. Results obtained showed that throughout the pre-process, the BSG microbiota was enriched in bacterial and fungal species of significant biotechnological and agronomic potential, including lactic acid bacteria (Weissella, Pediococcus), plant growth-promoting bacteria (Bacillus, Pseudomonas, Pseudoxhantomonas), and biostimulant yeasts (Pichia fermentans, Trichoderma reesei, Beauveria bassiana). Pre-processing increased the suitability of BSG for earthworms' activity to produce high-quality mature vermicompost.


Assuntos
Lactobacillales , Oligoquetos , Animais , Grão Comestível , Hypocreales , Pichia
2.
Chemosphere ; 287(Pt 1): 131902, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34438209

RESUMO

Understanding the lethal effects of pesticides nano formulations on the targeted organisms (pathogens) and the non-targeted organisms (fish, earthworms, etc) is essential in assessing the probable impact of new technologies on agriculture and environment. Here we evaluated the bioactivity and the biotoxicity of new type of fungicide smart-delivery formulation based on conjugating carboxymethylated-ß-glucans on the mesoporous silica nanoparticles (MSNs) surface after loading chlorothalonil (CHT) fungicide in the MSNs pores. The obtained formulation has been characterized with FE-SEM, and HR-TEM. The CHT loading efficiency has been measured with TGA. The bioactivity of the obtained formulation (CHT@MSNs-ß-glucans) has been tested against four pathogens, fusarium head blight (Fusarium graminearum), sheath rot (Sarocladium oryzae), rice sheath blight (Rhizoctonia solani), and soyabean anthracnose (Colletotrichum truncatum) compared with CHT WP 75% commercial formulation (CHT-WP) and technical CHT. The environmental biotoxicity of CHT@MSNs-ß-glucans compared with CHT-WP has been tested toward earthworm (Eisenia fetida) and zebra fish (Danio rerio). The results showed that CHT@MSNs-ß-glucans has an excellent bioactivity against the subjected pathogens with better inhabiting effects than CHT-WP. CHT@MSNs-ß-glucans toxicity to Eisenia fetida was found 2.25 times lower than CHT-WP toxicity. The LC50 of CHT@MSNs-ß-glucans to zebra fish after the first 24h was 2.93 times higher than CHT-WP. After 96h of treatment, the LC50 of CHT@MSNs-ß-glucans was 2.66 times higher than CHT-WP. This work highlighted the necessity to increase the mandatory bioassays of nano formulations with the major non-target organisms in the environmental risk assessment of new pesticide formulations.


Assuntos
Fungicidas Industriais , Nanopartículas , beta-Glucanas , Animais , Colletotrichum , Portadores de Fármacos , Fungicidas Industriais/toxicidade , Fusarium , Hypocreales , Nanopartículas/toxicidade , Nitrilas , Porosidade , Rhizoctonia , Dióxido de Silício/toxicidade , beta-Glucanas/toxicidade
3.
Braz J Biol ; 84: e253451, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34730701

RESUMO

Root-knot nematode Meloidogyne incognita is among the biotic factors which has greatly affected both the yield and the quality of the tomato crop. The egg parasitic nematode, Purpureocillium lilacinum (Pl) is considered as one of the most promising agents in controlling and overcoming this plant pathogen. The nematicidal effect of the native isolate Pl AUMC 10149 on second stage juvenile's survival and egg hatching of M. incognita at different times of exposure was tested in vitro. The obtained data showed that Pl gave a maximum percentage of J2 mortality (97.6%) and egg hatching inhibition (79.8%) after 72 hours of exposure. The potentiality of Pl as well as Bio-Nematon to control M. incognita infecting tomato was conducted using different times of application in vivo. Nine treatments with five replicates were used for such bioagents compared with the nematicide Oxamyl. Each seedling was inoculated with 1000 J2s of nematode/pot and 10 mL of Pl (1x1010 CFU/mL) or Bio-Nematon spore suspension (1x108 CFU/mL) 10mL/pot. The results indicated that the most effective treatments in reducing nematode population, number of galls and egg masses of M. incognita in plant roots was performed with treatment by Pl pre-planting and post-infection with Pl (Rf 1.9) giving a significant enhancement in plant length (64.9%), fresh weight (72.52%) and shoot dry weight (163.41%) without negatively impacting environment. Therefore, the present study confirmed that using P. lilacinum AUMC 10149 can be used as a practical supplement to environmentally friendly disease management of root-knot nematodes in Egypt.


Assuntos
Agentes de Controle Biológico , Hypocreales , Lycopersicon esculentum , Tylenchoidea , Animais , Lycopersicon esculentum/parasitologia , Tylenchoidea/patogenicidade
4.
BMC Genomics ; 22(1): 830, 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34789157

RESUMO

BACKGROUND: Trichoderma is a genus of fungi in the family Hypocreaceae and includes species known to produce enzymes with commercial use. They are largely found in soil and terrestrial plants. Recently, Trichoderma simmonsii isolated from decaying bark and decorticated wood was newly identified in the Harzianum clade of Trichoderma. Due to a wide range of applications in agriculture and other industries, genomes of at least 12 Trichoderma spp. have been studied. Moreover, antifungal and enzymatic activities have been extensively characterized in Trichoderma spp. However, the genomic information and bioactivities of T. simmonsii from a particular marine-derived isolate remain largely unknown. While we screened for asparaginase-producing fungi, we observed that T. simmonsii GH-Sj1 strain isolated from edible kelp produced asparaginase. In this study, we report a draft genome of T. simmonsii GH-Sj1 using Illumina and Oxford Nanopore technologies. Furthermore, to facilitate biotechnological applications of this species, RNA-sequencing was performed to elucidate the transcriptional profile of T. simmonsii GH-Sj1 in response to asparaginase-rich conditions. RESULTS: We generated ~ 14 Gb of sequencing data assembled in a ~ 40 Mb genome. The T. simmonsii GH-Sj1 genome consisted of seven telomere-to-telomere scaffolds with no sequencing gaps, where the N50 length was 6.4 Mb. The total number of protein-coding genes was 13,120, constituting ~ 99% of the genome. The genome harbored 176 tRNAs, which encode a full set of 20 amino acids. In addition, it had an rRNA repeat region consisting of seven repeats of the 18S-ITS1-5.8S-ITS2-26S cluster. The T. simmonsii genome also harbored 7 putative asparaginase-encoding genes with potential medical applications. Using RNA-sequencing analysis, we found that 3 genes among the 7 putative genes were significantly upregulated under asparaginase-rich conditions. CONCLUSIONS: The genome and transcriptome of T. simmonsii GH-Sj1 established in the current work represent valuable resources for future comparative studies on fungal genomes and asparaginase production.


Assuntos
Trichoderma , Asparaginase , Genoma , Hypocreales , Telômero , Trichoderma/genética
5.
Ulster Med J ; 90(3): 168-174, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34815596

RESUMO

Antimicrobial resistance (AMR) has now emerged as a major global public health problem. Certain bacterial pathogens, particularly Gram negative organisms associated with patients with cystic fibrosis (CF), have become resistant to several classes of antibiotics resulting in pan-resistance, which creates a clinical treatment dilemma. This study wished to explore the production of antibacterial extracellular metabolites from plant pathogenic fungi. Fungal Culture Extracts (FCEs) were prepared from 10 fungi (Armillaria gallica, Clitocybe nebularis, Fusarium coeruleum, Fusarium oxysporum, Fusarium poae, Hymenoscyphus fraxineus, Nectria fuckeliana, Phytophthora infestans, Phytophthora ramorum, Postia placenta), which were tested for activity against the CF pathogens, Pseudomonas aeruginosa (PA) (n=8), Burkholderia cenocepacia (n=2) and Stenotrophomonas maltophilia (n=2). In addition, FCE were assessed for their ability to alter antibiotic susceptibility in PA (n=8), with six antipseudomonal antibiotics (ceftazidime, ciprofloxacin, colistin, meropenem, piperacillin/tazobactam, tobramycin). None of the FCEs showed inhibitory activity to the 12 bacterial isolates tested, with the exception of the FCE from Postia placenta, which showed inhibition against all 12 bacteria. An antagonistic interaction was observed, where a statistically significant decrease in mean zone sizes was noted with Armillaria gallica (p=0.03) and Phytophthora infestans (p=0.03) FCEs and their interaction with the fluoroquinolone antibiotic, ciprofloxacin. Given the increase in clinical morbidity and mortality associated with chronic lung infections with Pseudomonas aeruginosa, Burkholderia cenocepacia and Stenotrophomonas maltophilia, coupled with the difficulty in treating such chronic infection due to overwhelming antimicrobial resistance, any novel substance showing inhibition of these organisms merits further investigation as a potential future antimicrobial agent, with potential clinical therapeutic application.


Assuntos
Basidiomycota , Burkholderia cenocepacia , Stenotrophomonas maltophilia , Agaricales , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Armillaria , Ascomicetos , Fungos , Fusarium , Humanos , Hypocreales , Polyporales , Pseudomonas aeruginosa
6.
Enzyme Microb Technol ; 152: 109923, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34688089

RESUMO

The filamentous fungus Trichoderma reesei is an extraordinarily efficient cell factory of industrial cellulase for production of biofuels and other bio-based products because of its excellent potential to secrete cellulolytic enzymes. Engineering the protein secretory pathway may be a powerful means for efficient protein production. However, it is uncertain whether this engineering approach could improve cellulase production in T. reesei. Herein, the endoplasmic reticulum (ER) secretory pathway was engineered for the production of cellulolytic enzymes by multiple strategies, including: (I) overexpression of the key components of protein folding (Pdi1, Ero1 and BiP); (II) overexpression of the glycosylation-related elements (Gpt1 and Gls2); (III) knockout of the ER mannosidase I (Mns1) encoding gene mns1. By utilizing these ER engineering strategies, the secretion of ß-glucosidase was remarkably elevated in the engineered strains, ranging from 29.2 % to 112.5 %. Furthermore, it was found that engineering these components also regulated the ER stress resistance. More importantly, the total cellulase production was increased with varying degrees, which reached a maximum of 149.4 %, using the filter paper assay (FPA) as a characterization method. These results demonstrated that engineering the ER secretory pathway can enhance protein secretion, particularly for cellulase production, which shed light for the development of high-efficient cellulolytic enzymes for economically feasible bioethanol production from lignocellulosic biomass.


Assuntos
Celulase , Trichoderma , Celulase/genética , Celulase/metabolismo , Retículo Endoplasmático/metabolismo , Hypocreales , Via Secretória , Trichoderma/genética , Trichoderma/metabolismo
7.
Molecules ; 26(19)2021 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-34641299

RESUMO

Increasing interest on sustainable agriculture has led to the development of new materials which can be used as seed coating agents. In this study, a new material was developed based on gelatin film reinforced with cellulose nanocrystals (CNC) which was further used as nanocomposite matrix for Trichoderma harzianum KUEN 1585 spores. The nanocomposite films were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and scanning electron microscopy (SEM), showing the formation of new hydrogen bonds between the components with a good compatibility between them. Measurements of water contact angles and tests of water vapor sorption and swelling degree revealed an improvement in the water vapor absorption properties of the films as a result of their reinforcement with CNC. Furthermore, by adding the Trichoderma harzianum KUEN 1585 spp. in the seed coating material, the germination percentage, speed of germination and roots length of the corn seeds improved. The polymeric coating did not inhibit the growth of T. harzianum KUEN 1585, with this material being a good candidate in modern agriculture.


Assuntos
Celulose/química , Gelatina/química , Hypocreales/fisiologia , Sementes/fisiologia , Zea mays/fisiologia , Germinação , Ligação de Hidrogênio , Microscopia Eletrônica de Varredura , Nanocompostos/química , Nanocompostos/microbiologia , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
8.
J Environ Sci (China) ; 109: 148-160, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34607663

RESUMO

Filamentous fungi can enter drinking water supply systems in various ways, and exist in suspended or sessile states which threatens the health of individuals by posing a high risk of invasive infections. In this study, the biofilms formation kinetics of the three genera of fungal spores, Aspergillus niger (A. niger), Penicillium polonicum (P. polonicum) and Trichoderma harzianum (T. harzianum) isolated from the groundwater were reported, as well as the effects of water quality parameters were evaluated. In addition, the efficiency of low- concentrations of chlorine-based disinfectants (chlorine, chlorine dioxide and chloramine) on controlling the formation of fungal biofilms was assessed. The results showed that the biofilms formation of the three genera of fungi could be divided into the following four phases: induction, exponential, stationary and sloughing off. The optimum conditions for fungal biofilms formation were found to be neutral or weakly acidic at 28 °C with rich nutrition. In fact, A. niger, P. polonicum, and T. harzianum were not observed to form mature biofilms in actual groundwater within 120 hr. Carbon was found to have the maximum effect on the fungal biofilms formation in actual groundwater, followed by nitrogen and phosphorus. The resistance of fungal species to disinfectants during the formation of biofilms decreased in the order: A. niger > T. harzianum > P. polonicum. Chlorine dioxide was observed to control the biofilms formation with maximum efficiency, followed by chlorine and chloramine. Consequently, the results of this study will provide a beneficial understanding for the formation and control of fungal biofilms.


Assuntos
Desinfetantes , Água Subterrânea , Penicillium , Purificação da Água , Biofilmes , Cloro , Fungos , Humanos , Hypocreales , Cinética
9.
Appl Microbiol Biotechnol ; 105(21-22): 8265-8276, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34661708

RESUMO

In the present work, the biotransformation of ginsenosides in white ginseng roots was innovatively investigated using the aerobic fermentation by the co-cultivation of Bacillus subtilis and Trichoderma reesei. It is found that in the co-cultivation mode, the optimal nitrogen source was corn steep liquor, and the loading of ginseng powder and inoculation proportion of B. subtilis and T. reesei were 15 g/L and 1:4, respectively. The total ginsenoside yield and production of minor ginsenosides in the co-cultivation mode obviously enhanced in comparison to the monoculture mode. Meanwhile, the maximal total ginsenoside yield of 21.79% and high hydrolase activities were achieved using the staged inoculation at the inoculation proportion of 1:4 in the co-cultivation mode, the production of minor ginsenosides such as Rg3 and Rh1, Rh2 was significantly strengthened, and the pharmacological activities of the fermented solution obviously improved. The enhancement of ginsenoside transformation can be mainly attributed to hydrolysis of the produced hydrolases and metabolism of two probiotics. This result clearly reveals that using the staged inoculation in co-cultivation fermentation mode was favor of the ginsenoside biotransformation in ginseng due to non-synchronous cell growth and different metabolic pathways of both probiotics. This work can provide a novel method for enhancing ginsenoside transformation of ginseng.Key points• Co-cultivation fermentation significantly promoted ginsenoside biotransformation.• The staged inoculation in co-culture mode was an optimal operation method.• The pharmacological activity of the co-cultured solution was significantly enhanced.


Assuntos
Ginsenosídeos , Panax , Trichoderma , Bacillus subtilis , Biotransformação , Hypocreales
10.
FEMS Microbiol Ecol ; 97(10)2021 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-34601593

RESUMO

European apple canker, caused by Neonectria ditissima, is a severe disease of apple. Achieving effective control is difficult with the currently available pesticides. Specific apple endophytes associated with cultivars may partially contribute to the cultivar response to the pathogen and thus could be used for disease management. We sought to determine whether the overall endophyte community differed among cultivars differing in their susceptibility to N. ditissima and to identify specific microbial groups associated with the susceptibility. Using Illumina MiSeq meta-barcoding, we profiled apple tree endophytes in 16 scion-rootstock combinations at two locations and quantified the relative contribution of scion, rootstock and location to the observed variability in the endophyte communities. Endophyte diversity was primarily affected by the orchard location (accounting for 29.4% and 85.9% of the total variation in the PC1 for bacteria and fungi, respectively), followed by the scion genotype (24.3% and 19.5% of PC2), whereas rootstock effects were small (<3% of PC1 and PC2). There were significant differences in the endophyte community between canker-resistant and -susceptible cultivars. Several bacterial and fungal endophyte groups had different relative abundance between susceptible and resistant cultivars. These endophyte groups included putative pathogen antagonists as well as plant pathogens. Their possible ecological roles in the N. ditissima pathosystem are discussed.


Assuntos
Hypocreales , Malus , Endófitos/genética , Genótipo , Doenças das Plantas
11.
Fungal Biol ; 125(11): 886-890, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34649675

RESUMO

An ancient fungal parasite of a Camponotus ant (Formicidae: Hymenoptera) in Baltic amber is described as Allocordyceps baltica gen. et sp. nov. (Hypocreales: Clavicipitaceae). The new genus is characterized by an orange, stalked, cup-shaped ascoma with partially immersed perithecia that emerges from the rectum of the ant, two separate stromata with septate mycelium that emerge from the base of the neck and the abdomen of the ant, respectively, and free-standing putative perithecia bearing putative asci with putative multicellular ascospores fragmented into one-celled partspores. This oldest known fossil fungus of an ant could represent a precursor of the genus Ophiocordyceps, which at present is the only fungal lineage parasitizing ants of the genus Camponotus. The fossil shows unique morphological features that existed in the Hypocreales some 35-55 MYA.


Assuntos
Formigas , Hypocreales , Parasitos , Âmbar , Animais , Fósseis , Hypocreales/genética
12.
Fungal Biol ; 125(11): 891-904, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34649676

RESUMO

Light is an important signal for fungi in the environment and induces many genes with roles in stress and virulence responses. Conidia of the entomopathogenic fungi Aschersonia aleyrodis, Beauveria bassiana, Cordyceps fumosorosea, Lecanicillium aphanocladii, Metarhizium anisopliae, Metarhizium brunneum, Metarhizium robertsii, Simplicillium lanosoniveum, Tolypocladium cylindrosporum, and Tolypocladium inflatum were produced on potato dextrose agar (PDA) medium under continuous white light, on PDA medium in the dark, or under nutritional stress (= Czapek medium without sucrose = MM) in the dark. The conidial tolerance of these species produced under these different conditions were evaluated in relation to heat stress, oxidative stress (menadione), osmotic stress (KCl), UV radiation, and genotoxic stress caused by 4-nitroquinoline 1-oxide (4-NQO). Several fungal species demonstrated greater stress tolerance when conidia were produced under white light than in the dark; for instance white light induced higher tolerance of A. aleyrodis to KCl and 4-NQO; B. bassiana to KCl and 4-NQO; C. fumosorosea to UV radiation; M. anisopliae to heat and menadione; M. brunneum to menadione, KCl, UV radiation, and 4-NQO; M. robertsii to heat, menadione, KCl, and UV radiation; and T. cylindrosporum to menadione and KCl. However, conidia of L. aphanocladii, S. lanosoniveum, and T. inflatum produced under white light exhibited similar tolerance as conidia produced in the dark. When conidia were produced on MM, a much stronger stress tolerance was found for B. bassiana to menadione, KCl, UV radiation, and 4-NQO; C. fumosorosea to KCl and 4-NQO; Metarhizium species to heat, menadione, KCl, and UV radiation; T. cylindrosporum to menadione and UV radiation; and T. inflatum to heat and UV radiation. Again, conidia of L. aphanocladii and S. lanosoniveum produced on MM had similar tolerance to conidia produced on PDA medium in the dark. Therefore, white light is an important factor that induces higher stress tolerance in some insect-pathogenic fungi, but growth in nutritional stress always provides in conidia with stronger stress tolerance than conidia produced under white light.


Assuntos
Beauveria , Metarhizium , Animais , Cordyceps , Hypocreales , Insetos , Iluminação , Esporos Fúngicos
13.
Fungal Biol ; 125(11): 934-949, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34649680

RESUMO

It is generally accepted that conidia, propagules of filamentous fungi, exist in the state of dormancy. This state is defined mostly phenomenologically, e.g., by germination requirements. Its molecular characteristics are scarce and are concentrated on the water or osmolyte content, and/or respiration. However, a question of whether conidia are metabolic or ametabolic forms of life cannot be answered on the basis of available experimental data. In other words, are mature conidia open thermodynamic systems as are mycelia, or do they become closed upon the transition to the dormant state? In this article, we present observations which may help to define the transition of freshly formed conidia to the putative dormant forms using measurements of selected enzyme activities, 1H- and 13C-NMR and LC-MS-metabolomes, and 14C-bicarbonate or 45Ca2+ inward transport. We have found that Trichoderma atroviride and Aspergillus niger conidia arrest the 45Ca2+ uptake during the development stopping thereby the cyclic (i.e., bidirectional) Ca2+ flow existing in vegetative mycelia and conidia of T. atroviride across the cytoplasmic membrane. Furthermore, we have found that the activity of α-ketoglutarate dehydrogenase was rendered completely inactive after 3 weeks from the conidia formation unlike of other central carbon metabolism enzymes. This may explain the loss of conidial respiration. Finally, we found that conidia take up the H14CO3- and convert it into few stable compounds within 80 d of maturation, with minor quantitative differences in the extent of this process. The uptake of H13CO3- confirmed these observation and demonstrated the incorporation of H13CO3- even in the absence of exogenous substrates. These results suggest that T. atroviride conidia remain metabolically active during first ten weeks of maturation. Under these circumstances, their metabolism displays features similar to those of chemoautotrophic microorganisms. However, the Ca2+ homeostasis changed from the open to the closed thermodynamic state during the early period of conidial maturation. These results may be helpful for studying the conidial ageing and/or maturation, and for defining the conidial dormant state in biochemical terms.


Assuntos
Trichoderma , Aspergillus niger , Hypocreales , Micélio , Esporos Fúngicos
14.
J Agric Food Chem ; 69(43): 12695-12704, 2021 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-34677054

RESUMO

The Pal/Rim pathway and its key transcription factor PacC play important roles in fungal adaptation to ambient pH regarding growth, secondary metabolism, and virulence. However, the effect of PacC on the secondary metabolism of the important biocontrol fungus Trichoderma harzianum remains elusive. To answer this question, ThpacC deletion (KO-ThpacC) and overexpression (OE-ThpacC) mutants of T. harzianum 3.9236 were constructed. Transcriptomic analysis of T. harzianum and KO-ThpacC suggested that ThpacC acted as both a positive and a negative regulator for secondary metabolite (SM) production. Further investigation revealed that deletion of ThpacC abolished homodimericin A and 8-epi-homodimericin A production. Moreover, ThpacC plays a role in the antagonism of T. harzianum against Sclerotinia sclerotiorum. 8-epi-Homodimericin A demonstrated moderate inhibitory activity against S. sclerotiorum. Our results contribute to a deeper understanding of the ThpacC function on SM production and the antifungal activity of T. harzianum.


Assuntos
Ascomicetos , Trichoderma , Antifúngicos/farmacologia , Hypocreales , Trichoderma/genética
15.
Curr Microbiol ; 78(12): 4115-4126, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34668992

RESUMO

Grey mould caused by Botrytis cinerea leads to severe economic loss on commercial tomato production. Application of beneficial microorganism offers an eco-friendly alternative for mitigation of tomato fungal disease damage, considering negative influences of fungicides. In the present study, an antagonistic Trichoderma afroharzianum isolate TM24 was evaluated for its biocontrol potential on tomato grey mould. The isolate TM24 showed obviously antagonistic effect on B. cinerea mycelium growth and production of glucanase and chitinase. Leaf spraying with spore suspension of isolate TM24 showed a biocontrol efficiency of over 54% against tomato grey mould in greenhouse pot experiment. The activities of plant defense-related enzymes including polyphenol oxidase, phenylalanine ammonialyase, superoxide dismutase, and peroxidase were all increased to varying degrees in tomato leaves after isolate TM24 treatment. Transcriptome analysis showed that, a total of 1941, 1753 and 38 differentially expressed genes (DEGs) were obtained at 24, 48 and 72 hpi, respectively, in tomato leaves pretreated with T. afroharzianum TM24, and then challenged with B. cinerea inoculation. The DEGs were mainly enriched in MAPK signaling pathway and plant hormones signal transduction pathway. Multiple genes that regulated crucial nodes of defense-related pathways, like flavonoid, phenylpropanoid, jasmonic acid and ethylene metabolisms were also identified, which may have positive correlations with the biocontrol potential of isolate TM24 in tomato plants. These promising results provided valuable information on using T. afroharzianum TM24 as a beneficial biocontrol agent in tomato grey mould management.


Assuntos
Lycopersicon esculentum , Trichoderma , Botrytis , Hypocreales , Doenças das Plantas
16.
An Acad Bras Cienc ; 93(suppl 3): e20201159, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34468490

RESUMO

This study analysed the mycobiota on exoskeleton debris of the crab Neohelice granulata collected from an alkaline salt marsh and assessed the in vitro enzyme ability of selected isolates at different temperatures and pH. Exoskeleton fragments were incubated in moist chambers on paper and on agar medium. Growth and enzyme ability of selected fungi were also evaluated in agar media with 0.5 % casein, 1% Tween®20, and Chitin-Azure® by the production of a halo/growth ratio. We identified 22 fungal species using both methods. Since the two isolation methods added information to one another, both ones are necessary to recover the cultivable mycobiota associated with the exoskeleton debris. All fungi showed greater levels of enzyme activity in alkaline than acid medium with Tween®20. The halo diameter on casein and chitin varied according to the fungal isolate and pH. Most fungi had a larger halo at 4°C than at the other temperatures tested. Clonostachys rosea showed the greatest activity in all media at 4ºC. We conclude that exoskeletons of the N. granulata are a source of fungi able to produce enzyme activities that show differences upon incubation conditions to which they are cultivated such as ones including specific temperatures and pH values.


Assuntos
Braquiúros , Exoesqueleto Energizado , Animais , Concentração de Íons de Hidrogênio , Hypocreales , Temperatura , Áreas Alagadas
17.
J Agric Food Chem ; 69(38): 11303-11310, 2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34542281

RESUMO

Liver fibrosis has accounted for liver diseases and overall mortality, but no relevant drug has been developed. Filamentous fungi are important resources of natural products for pharmaceutical development. Calcarisporium arbuscula is a mushroom endophytic fungus, which primarily produces aurovertins. Here, in an aurovertin null-production mutant, one silent gene cluster (mca17) was activated by overexpression of a pathway-specific zinc finger transcriptional regulator, and a tetramic acid-type compound (1, MCA17-1) was identified. Along with detailed structural characterization, its biosynthesis was proposed to be produced from the core PKS-NRPS hybrid enzyme. Moreover, 1 suppressed the activation of LX-2 upon transforming growth factor-ß (TGF-ß) challenge and had stronger bioactivity than the positive control obeticholic acid (OCA) against liver fibrosis. Our work suggested that this engineered fungus could be a producer of 1 for promising pharmaceutical development, and alternatively, it would be developed as a mushroom ingredient in dietary therapy to prevent liver fibrosis.


Assuntos
Agaricales , Hypocreales , Agaricales/genética , Humanos , Hypocreales/genética , Cirrose Hepática/genética , Família Multigênica
18.
Nat Commun ; 12(1): 5300, 2021 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-34489427

RESUMO

Isobutene is a high value gaseous alkene used as fuel additive and a chemical building block. As an alternative to fossil fuel derived isobutene, we here develop a modified mevalonate pathway for the production of isobutene from glucose in vivo. The final step in the pathway consists of the decarboxylation of 3-methylcrotonic acid, catalysed by an evolved ferulic acid decarboxylase (Fdc) enzyme. Fdc belongs to the prFMN-dependent UbiD enzyme family that catalyses reversible decarboxylation of (hetero)aromatic acids or acrylic acids with extended conjugation. Following a screen of an Fdc library for inherent 3-methylcrotonic acid decarboxylase activity, directed evolution yields variants with up to an 80-fold increase in activity. Crystal structures of the evolved variants reveal that changes in the substrate binding pocket are responsible for increased selectivity. Solution and computational studies suggest that isobutene cycloelimination is rate limiting and strictly dependent on presence of the 3-methyl group.


Assuntos
Alcenos/metabolismo , Carboxiliases/metabolismo , Proteínas de Escherichia coli/metabolismo , Escherichia coli/enzimologia , Mononucleotídeo de Flavina/química , Glucose/metabolismo , Alcenos/química , Biocatálise , Carboxiliases/genética , Crotonatos/metabolismo , Evolução Molecular Direcionada/métodos , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Fermentação , Mononucleotídeo de Flavina/metabolismo , Glucose/química , Hypocreales/enzimologia , Hypocreales/genética , Ácido Mevalônico/metabolismo , Prenilação
19.
Biocontrol Sci ; 26(3): 157-166, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34556618

RESUMO

We isolated a fungus from a 20% (= 200,000 µg/mL) aqueous solution of polyhexamethylene biguanide hydrochloride (PHMB), a widely used antimicrobial and examined its morphology and drug resistance profile. Based on the sequence of the internal transcribed spacer region of ribosomal DNA, the fungus was identified as Purpureocillium lilacinum. Although the P. lilacinum type and resistant strains showed similar morphology, the latter had extremely low PHMB susceptibility and was able to grow in 20% aqueous solution of PHMB, which eliminated the type strain. The minimum inhibitory concentration (MIC) of PHMB for the resistant strain was significantly higher than that of the type strain and other pathogenic filamentous fungi and yeasts. The susceptibility to antimicrobial agents and antifungal agents other than PHMB was similar to that of the type strain, therefore the drug resistance of the isolate was specific to PHMB. Furthermore, we sequenced the genome of the isolate to predict PHMB resistance-related genes. Despite its high resistance to PHMB, no well-known genes homologous to fungal PHMB-resistant genes were detected in the genome of the resistant strain. In summary, P. lilacinum was found to be significantly more resistant to PHMB than previously reported, via an unidentified mechanism of drug resistance.


Assuntos
Biguanidas , Fungos , Biguanidas/farmacologia , Hypocreales , Testes de Sensibilidade Microbiana
20.
Artigo em Inglês | MEDLINE | ID: mdl-34574855

RESUMO

A wide range of root-associated mutualistic microorganisms have been successfully applied and documented in the past for growth promotion, biofertilization, biofortification and biotic and abiotic stress amelioration in major crops. These microorganisms include nitrogen fixers, nutrient mobilizers, bio-remediators and bio-control agents. The present study aimed to demonstrate the impact of salt-tolerant compatible microbial inoculants on plant growth; Zn biofortification and yield of wheat (Triticum aestivum L.) crops grown in saline-sodic soil and insight of the mechanisms involved therein are being shared through this paper. Field experiments were conducted to evaluate the effects of Trichoderma harzianum UBSTH-501 and Bacillus amyloliquefaciens B-16 on wheat grown in saline-sodic soil at Research Farm, ICAR-Indian Institute of Seed Sciences, Kushmaur, India. The population of rhizosphere-associated microorganisms changed dramatically upon inoculation of the test microbes in the wheat rhizosphere. The co-inoculation induced a significant accumulation of proline and total soluble sugar in wheat at 30, 60, 90 and 120 days after sowing as compared to the uninoculated control. Upon quantitative estimation of organic solutes and antioxidant enzymes, these were found to have increased significantly in co-inoculated plants under salt-stressed conditions. The application of microbial inoculants enhanced the salt tolerance level significantly in wheat plants grown in saline-sodic soil. A significant increase in the uptake and translocation of potassium (K+) and calcium (Ca2+) was observed in wheat co-inoculated with the microbial inoculants, while a significant reduction in sodium (Na+) content was recorded in plants treated with both the bio-agents when compared with the respective uninoculated control plants. Results clearly indicated that significantly higher expression of TaHKT-1 and TaNHX1 in the roots enhances salt tolerance effectively by maintaining the Na+/K+ balance in the plant tissue. It was also observed that co-inoculation of the test inoculants increased the expression of ZIP transporters (2-3.5-folds) which ultimately led to increased biofortification of Zn in wheat grown in saline-sodic soil. Results suggested that co-inoculation of T. harzianum UBSTH-501 and B. amyloliquefaciens B-16 not only increased plant growth but also improved total grain yield along with a reduction in seedling mortality in the early stages of crop growth. In general, the present investigation demonstrated the feasibility of using salt-tolerant rhizosphere microbes for plant growth promotion and provides insights into plant-microbe interactions to ameliorate salt stress and increase Zn bio-fortification in wheat.


Assuntos
Inoculantes Agrícolas , Triticum , Biofortificação , Hypocreales , Raízes de Plantas , Solo , Zinco
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