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1.
Braz. j. biol ; 84: e253451, 2024. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1345553

RESUMO

Abstract 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.


Resumo O nematoide-das-galhas Meloidogyne incognita está entre os fatores bióticos que afetaram enormemente a produção e a qualidade da cultura do tomate. O nematoide parasita de ovos, Purpureocillium lilacinum (Pl), é considerado um dos mais promissores agentes no controle e superação desse fitopatógeno. O efeito nematicida do isolado nativo Pl AUMC 10149 na sobrevivência de juvenis de segundo estágio e na eclosão dos ovos de M. incognita em diferentes momentos de exposição foi testado in vitro. Os dados obtidos mostraram que o Pl deu um percentual máximo de mortalidade de J2 (97.6%) e inibição da eclosão dos ovos (79.8%) após 72 horas de exposição. A potencialidade de Pl e de Bio-Nematon para controlar M. incognita infectando tomate foi conduzida em diferentes tempos de aplicação in vivo. Nove tratamentos com cinco repetições foram usados ​​para tais bioagentes em comparação com o nematicida Oxamyl. Cada muda foi inoculada com 1.000 J2s de nematoide / vaso e 10 mL de Pl (1×1010 CFU/mL). Ou suspensão de esporos Bio-Nematon (1×108 CFU/mL) 10mL/pot. Os resultados indicaram que os tratamentos mais eficazes na redução da população de nematoides, número de galhas e desovas de M. incognita nas raízes das plantas foram realizados com Pl pré-plantio e pós-infecção com Pl (Rf 1.9), dando um aumento significativo no comprimento da planta (64.9%), massa fresca (72.52%) e massa seca da parte aérea (163.41%) sem impactar negativamente o meio ambiente. Portanto, o presente estudo confirmou que o uso de P. lilacinum AUMC 10149 pode ser usado como um suplemento prático para o manejo ecologicamente correto de nematoides-das-galhas no Egito.


Assuntos
Animais , Tylenchoidea/patogenicidade , Lycopersicon esculentum/parasitologia , Agentes de Controle Biológico , Hypocreales
2.
Arch Microbiol ; 204(10): 620, 2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-36100763

RESUMO

The biogenic method for synthesis of nanoparticles is preferred over the traditional strategies, on account of its ease, environmental friendliness, and cost-effectivity, wherein fungi endorse themselves to be the most appropriate precursor for the same. In recent times numerous metal nanoparticles have been reported to exhibit significant therapeutic activities, out of which Zinc Oxide nanoparticles (ZnO NPs) stand apart on account of their multidimensional nature. Thus, this study was carried out with an aim to biosynthesize ZnO NPs utilizing endophyte Trichoderma viride, isolated from the seeds of Momordica charantia. The physicochemical characterization of NPs was done via employing a combination of spectroscopic and microscopic techniques. The NPs were found to have a hexagonal shape and possessed an average particle size of around 63.3 nm. The antimicrobial activity of NPs was evaluated against multi-drug resistant organisms and it was observed to be an appreciable one whereas the antioxidant activity was deduced to be dose-dependent. Thus, these ZnO NPs can be considered as a probable active ingredient of any future therapeutic conceptualization after undertaking a thorough toxicological assessment.


Assuntos
Anti-Infecciosos , Hypocreales , Nanopartículas Metálicas , Óxido de Zinco , Antibacterianos/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Endófitos , Nanopartículas Metálicas/química , Óxido de Zinco/química , Óxido de Zinco/farmacologia
3.
PLoS One ; 17(9): e0273985, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36067200

RESUMO

The present study aimed to examine the capability of Clonostachys rosea isolates as a biological control agent against grapevine trunk diseases pathogens. Five C. rosea and 174 pathogenic fungal strains were isolated from grafted grapevines and subjected to in vitro confrontation tests. Efficient antagonism was observed against Eutypa lata and Phaeomoniella chlamydospora while mycoparasitism was observed to the pathogens of Botryosphaeria dothidea and Diaporthe spp. pathogens in in vitro dual culture assays. The conidia production of the C. rosea isolates were also measured on PDA plates. One isolate (19B/1) with high antagonistic capabilities and efficient conidia production was selected for in planta confrontation tests by mixing its conidia with the soil of Cabernet sauvignon grapevine cuttings artificially infected with B. dothidea, E. lata and P. chlamydospora. The length and/or the incidence of necrotic lesions caused by E. lata and P. chlamydospora at the inoculation point were significantly decreased after a three months incubation in the greenhouse on cuttings planted in soils inoculated with the conidia of strain 19B/1, while symptom incidence and severity were unaffected in the case of the pathogen B. dothidea. Based on the above results, we consider C. rosea a promising biological control agent against some grapevine trunk diseases.


Assuntos
Agentes de Controle Biológico , Hypocreales , Agentes de Controle Biológico/farmacologia , Hypocreales/fisiologia , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Esporos Fúngicos
4.
BMC Plant Biol ; 22(1): 452, 2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36131258

RESUMO

BACKGROUND: European canker, caused by the fungal pathogen Neonectria ditissima, is an economically damaging disease in apple producing regions of the world - especially in areas with moderate temperatures and high rainfall. The pathogen has a wide host range of hardwood perennial species, causing trunk cankers, dieback and branch lesions in its hosts. Although apple scion germplasm carrying partial resistance to the disease has been described, little is still known of the genetic basis for this quantitative resistance. RESULTS: Resistance to Neonectria ditissima was studied in a multiparental population of apple scions using several phenotyping methods. The studied population consists of individuals from multiple families connected through a common pedigree. The degree of disease of each individual in the population was assessed in three experiments: artificial inoculations of detached dormant shoots, potted trees in a glasshouse and in a replicated field experiment. The genetic basis of the differences in disease was studied using a pedigree-based analysis (PBA). Three quantitative trait loci (QTL), on linkage groups (LG) 6, 8 and 10 were identified in more than one of the phenotyping strategies. An additional four QTL, on LG 2, 5, 15 and 16 were only identified in the field experiment. The QTL on LG2 and 16 were further validated in a biparental population. QTL effect sizes were small to moderate with 4.3 to 19% of variance explained by a single QTL. A subsequent analysis of QTL haplotypes revealed a dynamic response to this disease, in which the estimated effect of a haplotype varied over the field time-points. CONCLUSIONS: This study describes the first identified QTL associated with resistance to N. ditissima in apple scion germplasm. The results from this study show that QTL present in germplasm commonly used in apple breeding have a low to medium effect on resistance to N. ditissima. Hence, multiple QTL will need to be considered to improve resistance through breeding.


Assuntos
Hypocreales , Malus , Resistência à Doença/genética , Hypocreales/fisiologia , Malus/genética , Malus/microbiologia , Melhoramento Vegetal , Doenças das Plantas/genética , Doenças das Plantas/microbiologia
5.
Chem Biodivers ; 19(9): e202200627, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35921066

RESUMO

Total 23 eleven-residue peptaibols, including five reported ones (1-5) in our previous work, were isolated from the fungus Trichoderma longibrachiatum Rifai DMG-3-1-1, which was obtained from the mushroom Clitocybe nebularis (Batsch) P. Kumm. The structures of the 13 new peptaibols (6-10 and 12-19) were determined by their NMR and MALDI-MS/MS data, their absolute structures were further determined by Marfey's analyses and their ECD data. Careful comparison of the structures of 1-23 showed that only seven residues varied including the 2nd (Gln2 /Asn2 ), 3rd (Ile3 /Val3 ), 4th (Ile4 /Val4 ), 6th (Pro6 /Hyp6 ), 8th (Leu8 /Val8 ), 10th (Pro10 /Hyp10 ) and 11th (Leuol11 /Ileol11 /Valol11 ) residues. Comparison of the IC50 s against the three tested cell lines of 1-23 indicated that 2nd, 3rd and 4th amino acid residues affected their cytotoxicities powerfully. Compounds 2, 5, 9, 11, 21 and 22 showed moderate antibacterial activities against Staphylococcus aureus MRSA T144, which also showed stronger cytotoxicities against BV2 and MCF-7 cells.


Assuntos
Peptaibols , Trichoderma , Aminoácidos/metabolismo , Antibacterianos/química , Hypocreales , Peptaibols/química , Peptaibols/farmacologia , Relação Estrutura-Atividade , Espectrometria de Massas em Tandem , Trichoderma/química
6.
J Med Entomol ; 59(5): 1732-1740, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-35938709

RESUMO

Aedes aegypti mosquitoes are capable of vectoring a wide range of diseases including dengue, yellow fever, and Zika viruses, with approximately half of the worlds' population at risk from such diseases. Development of combined predator-parasite treatments for the control of larvae consistently demonstrates increased efficacy over single-agent treatments, however, the mechanism behind the interaction remains unknown. Treatments using the natural predator Toxorhynchites brevipalpis and the entomopathogenic fungus Metarhizium brunneum were applied in the laboratory against Ae. aegypti larvae as both individual and combined treatments to determine the levels of interaction between control strategies. Parallel experiments involved the removal of larvae from test arenas at set intervals during the course of the trial to record whole body caspase and phenoloxidase activities. This was measured via luminometric assay to measure larval stress factors underlying the interactions. Combined Metarhizium and Toxorhynchites treatments were seen to drastically reduce lethal times as compared to individual treatments. This was accompanied by increased phenoloxidase and caspase activities in combination treatments after 18 h (p < 0.001). The sharp increases in caspase and phenoloxidase activities suggest that combined treatments act to increase stress factor responses in the larvae that result in rapid mortality above that of either control agent individually. This work concludes that the underlying mechanism for increased lethality in combined parasite-predator treatments may be related to additive stress factors induced within the target host larvae.


Assuntos
Aedes , Culicidae , Hypocreales , Metarhizium , Infecção por Zika virus , Zika virus , Aedes/fisiologia , Animais , Caspases , Larva/fisiologia , Metarhizium/fisiologia , Monofenol Mono-Oxigenase , Controle de Mosquitos
7.
PLoS One ; 17(8): e0272702, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35947630

RESUMO

Watermelon (Citrullus lanatus) is one of the most popular fruit crops. However, Fusarium wilt (FW) is a serious soil-borne disease caused by Fusarium oxysporum f. sp. niveum (FON) that severely limits the development of the watermelon industry. Trichoderma spp. is an important plant anti-pathogen biocontrol agent. The results of our previous study indicated that Trichoderma asperellum M45a (T. asperellum M45a) could control FW by enhancing the relative abundance of plant growth-promoting rhizobacteria (PGPR) in the rhizosphere of watermelon. However, there are few studies on its mechanism in the pathogen resistance of watermelon. Therefore, transcriptome sequencing of T. asperellum M45a-treated watermelon roots combined with metabolome sequencing of the rhizosphere soil was performed with greenhouse pot experiments. The results demonstrated that T. asperellum M45a could stably colonize roots and significantly increase the resistance-related enzymatic activities (e.g., lignin, cinnamic acid, peroxidase and peroxidase) of watermelon. Moreover, the expression of defense-related genes such as MYB and PAL in watermelon roots significantly improved with the inoculation of T. asperellum M45a. In addition, KEGG pathway analysis showed that a large number of differentially expressed genes were significantly enriched in phenylpropane metabolic pathways, which may be related to lignin and cinnamic acid synthesis, thus further inducing the immune response to resist FON. Furthermore, metabolic analysis indicated that four differential metabolic pathways were enriched in M45a-treated soil, including six upregulated compounds and one down-regulated compound. Among them, galactinol and urea were significantly positively correlated with Trichoderma. Hence, this study provides insight into the biocontrol mechanism of T. asperellum M45a to resist soil-borne diseases, which can guide its industrial application.


Assuntos
Citrullus , Fusarium , Trichoderma , Citrullus/genética , Fusarium/fisiologia , Hypocreales , Lignina , Peroxidases , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Solo , Transcriptoma , Trichoderma/genética
8.
Parasitol Res ; 121(10): 2979-2984, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35994116

RESUMO

Aedes aegypti (Linnaeus, 1762) is an important vector of arboviruses in the tropics and subtropics. New control strategies based on natural enemies such as entomopathogenic fungi are of utmost importance, and the present study reports the first isolation of Clonostachys spp. (Hypocreales: Bionectriaceae) from mosquitoes and their activity against A. aegypti. Entomopathogenic fungi were surveyed in central Brazil using A. aegypti larvae as sentinels and, also, a CDC light trap. Clonostachys eriocamporesii R.H. Perera & K.D. Hyde, 2020 (IP 440) and Clonostachys byssicola Schroers, 2001 (IP 461) were identified by sequence analysis of the nuclear ribosomal internal transcribed spacer gene, and tested against eggs, larvae, and adults. Both strains were highly active against A. aegypti third instar larvae, with mortalities ≥ 80% at 107 conidia/mL after 5 days but distinctly less active against eggs and adults. This is the first report of both C. eriocamporesii and C. byssicola as naturally occurring pathogens affecting mosquitoes, and IP 440 appears to be a promising control agent against aquatic stages of A. aegypti.


Assuntos
Aedes , Hypocreales , Aedes/microbiologia , Animais , Larva/microbiologia , Controle de Mosquitos , Mosquitos Vetores , Esporos Fúngicos
9.
Microbiol Spectr ; 10(4): e0154222, 2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-35943267

RESUMO

Phytophthora nicotianae is an oomycete pathogen of global significance threatening many important crops. It is mainly controlled by chemosynthetic fungicides, which endangers ecosystem and human health; thus, there is an urgent need to explore alternatives for these fungicides. In this study, a new anti-oomycete aliphatic compound, 2E,4E-decadienoic acid (DDA), was obtained through coculture of Bacillus subtilis Tpb55 and Trichoderma asperellum HG1. Both in vitro and in vivo tests showed that DDA had a strong inhibitory effect against P. nicotianae. In addition, rhizosphere microbiome analysis showed that DDA reduced the relative abundance of Oomycota in rhizosphere soil. Transcriptome sequencing (RNA-Seq) analysis revealed that treatment of P. nicotianae with DDA resulted in significant downregulation of antioxidant activity and energy metabolism, including antioxidant enzymes and ATP generation, and upregulation of membrane-destabilizing activity, such as phospholipid synthesis and degradation. The metabolomic analysis results implied that the pathways influenced by DDA were mainly related to carbohydrate metabolism, energy metabolism, and the cell membrane. The biophysical tests further indicated that DDA produced oxidative stress on P. nicotianae, inhibited antioxidant enzyme and ATPase activity, and increased cell membrane permeability. Overall, DDA exerts inhibitory activity by acting on multiple targets in P. nicotianae, especially on the cell membrane and mitochondria, and can therefore serve as a novel environment-friendly agent for controlling crop oomycete disease. IMPORTANCE P. nicotianae is an oomycete pathogen that is destructive to crops. Although some oomycete inhibitors have been used during crop production, most are harmful to the ecology and lead to pathogen resistance. Alternatively, medium-chain fatty acids have been reported to exhibit antimicrobial activity in the medical field in previous studies; however, their potential as biocontrol agents has rarely been evaluated. Our in vivo and in vitro analyses revealed that the medium-chain fatty acid 2E,4E-decadienoic acid (DDA) displayed specific inhibitory activity against oomycetes. Further analysis indicated that DDA may acted on multiple targets in P. nicotianae, especially on the cell membrane and mitochondria. Our findings highlight the potential of DDA in controlling oomycete diseases. In conclusion, these results provide insights regarding the future use of green and environment-friendly anti-oomycete natural products for the prevention and control of crop oomycete diseases.


Assuntos
Fungicidas Industriais , Phytophthora , Antioxidantes/farmacologia , Bacillus subtilis , Técnicas de Cocultura , Produtos Agrícolas , Ecossistema , Fungicidas Industriais/farmacologia , Humanos , Hypocreales , Doenças das Plantas/prevenção & controle
10.
Elife ; 112022 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-35950750

RESUMO

Circadian clocks are important for an individual's fitness, and recent studies have underlined their role in the outcome of biological interactions. However, the relevance of circadian clocks in fungal-fungal interactions remains largely unexplored. We sought to characterize a functional clock in the biocontrol agent Trichoderma atroviride to assess its importance in the mycoparasitic interaction against the phytopathogen Botrytis cinerea. Thus, we confirmed the existence of circadian rhythms in T. atroviride, which are temperature-compensated and modulated by environmental cues such as light and temperature. Nevertheless, the presence of such molecular rhythms appears to be highly dependent on the nutritional composition of the media. Complementation of a clock null (Δfrq) Neurospora crassa strain with the T. atroviride-negative clock component (tafrq) restored core clock function, with the same period observed in the latter fungus, confirming the role of tafrq as a bona fide core clock component. Confrontation assays between wild-type and clock mutant strains of T. atroviride and B. cinerea, in constant light or darkness, revealed an inhibitory effect of light on T. atroviride's mycoparasitic capabilities. Interestingly, when confrontation assays were performed under light/dark cycles, T. atroviride's overgrowth capacity was enhanced when inoculations were at dawn compared to dusk. Deleting the core clock-negative element FRQ in B. cinerea, but not in T. atroviride, was vital for the daily differential phenotype, suggesting that the B. cinerea clock has a more significant influence on the result of this interaction. Additionally, we observed that T. atroviride clock components largely modulate development and secondary metabolism in this fungus, including the rhythmic production of distinct volatile organic compounds (VOCs). Thus, this study provides evidence on how clock components impact diverse aspects of T. atroviride lifestyle and how daily changes modulate fungal interactions and dynamics.


Assuntos
Botrytis , Proteínas CLOCK , Ritmo Circadiano , Proteínas Fúngicas , Hypocreales , Interações Microbianas , Metabolismo Secundário , Botrytis/crescimento & desenvolvimento , Botrytis/metabolismo , Botrytis/efeitos da radiação , Proteínas CLOCK/metabolismo , Ritmo Circadiano/efeitos da radiação , Proteínas Fúngicas/metabolismo , Hypocreales/crescimento & desenvolvimento , Hypocreales/metabolismo , Hypocreales/efeitos da radiação , Luz , Temperatura
11.
Hereditas ; 159(1): 31, 2022 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-35953844

RESUMO

BACKGROUND: Apple production in Sweden and elsewhere is being threatened by the fungus, Neonectria ditissima, which causes a disease known as European canker. The disease can cause extensive damage and the removal of diseased wood and heavily infected trees can be laborious and expensive. Currently, there is no way to eradicate the fungus from infected trees and our knowledge of the infection process is limited. Thus, to target and modify genes efficiently, the genetic transformation technique developed for N. ditissima back in 2003 was modified. RESULTS: The original protocol from 2003 was upgraded to use enzymes currently available in the market for making protoplasts. The protoplasts were viable, able to uptake foreign DNA, and able to regenerate back into a mycelial colony, either as targeted gene-disruption mutants or as ectopic mutants expressing the green fluorescent protein (GFP). CONCLUSIONS: A new genetic transformation protocol has been established and the inclusion of hydroxyurea in the buffer during the protoplast-generation step greatly increased the creation of knockout mutants via homologous recombination. Pathogenicity assays using the GFP-mutants showed that the mutants were able to infect the host and cause disease.


Assuntos
Hypocreales , Malus , Hypocreales/genética , Malus/genética , Malus/microbiologia , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Árvores/microbiologia
12.
Int J Mol Sci ; 23(16)2022 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-36012636

RESUMO

Lipases are enzymes that hydrolyze triglycerides to fatty acids and glycerol. A typical element in lipases is a conserved motif of five amino acids (the pentapeptide), most commonly G-X-S-X-G. Lipases with the pentapeptide A-X-S-X-G are present in species of Bacillus, Paucimonas lemoignei, and the yeast Trichosporon asahii; they are usually thermotolerant and solvent resistant. Recently, while searching for true lipases in the Trichoderma harzianum genome, one lipase containing the pentapeptide AHSMG was identified. In this study, we cloned from T. harzianum strain B13-1 the lipase ID135964, renamed here as ThaL, which is 97.65% identical with the reference. We found that ThaL is a lid-containing true lipase of cluster III that belongs to a large family comprising highly conserved proteins in filamentous fungi in the orders Hypocreales and Glomerellales, in which predominantly pathogenic fungi are found. ThaL was expressed in conidia, as well as in T. harzianum mycelium, where it was cultured in liquid minimal medium. These results-together with the amino acid composition, absence of a signal peptide, mitochondrial sorting prediction, disordered regions in the protein, and lineage-specific phylogenetic distribution of its homologs-suggest that ThaL is a non-canonical effector. In summary, AHSMG-lipase is a novel lipase family in filamentous fungi, and is probably involved in pathogenicity.


Assuntos
Bacillus , Hypocreales , Bacillus/metabolismo , Fungos/metabolismo , Hypocreales/metabolismo , Lipase/metabolismo , Filogenia , Pseudomonas/metabolismo
13.
Bioprocess Biosyst Eng ; 45(9): 1581-1593, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35932338

RESUMO

Chlorophenols are widely used in industry and are known environmental pollutants. The degradation of chlorophenols is important for environmental remediation. In this study, we evaluated the biodegradation of 2-chlorophenol using crude laccase produced by Myrothecium verrucaria. Atmospheric and room temperature plasma technology was used to increase laccase production. The culture conditions of the M-6 mutant were optimized. Our results showed that corn stover could replace glucose as a carbon source and promote laccase production. The maximum laccase activity of 30.08 U/mL was achieved after optimization, which was a 19.04-fold increase. The biodegradation rate of 2-chlorophenol using crude laccase was 97.13%, a positive correlation was determined between laccase activity and degradation rate. The toxicity of 2-CP was substantially reduced after degradation by laccase solution. Our findings show the feasibility of the use of corn stover in laccase production by M. verrucaria mutant and the subsequent biodegradation of 2-chlorophenol using crude laccase.


Assuntos
Clorofenóis , Lacase , Biodegradação Ambiental , Carbono , Clorofenóis/metabolismo , Hypocreales , Zea mays
14.
Carbohydr Polym ; 295: 119876, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-35989016

RESUMO

This study proposes the use of green matrices of cellulose nanocrystals (CNC) and a nanocomposite of CNC with carboxymethyl cellulose (CMC) for efficiently encapsulating the plant biocontrol agent Trichoderma harzianum. Beads containing spores of the microorganism were produced by dripping dispersions of the polymers into a CaCl2 coagulation bath, resulting in the crosslinking of CNC chains by Ca2+ ions. SEM micrographs evidenced the T. harzianum spores in the encapsulation matrices. X-ray microtomography confirmed the random distribution of the microorganism within the polymeric matrix and the presence of internal pores in the CNC:CMC:spores beads. Encapsulation in the CNC:CMC nanocomposite favored growth of the fungus after 10 days of storage at room temperature, which could be attributed to the presence of internal pores and to the extra carbon source provided by the CMC. The results indicated that CNC:CMC nanocomposites are promising materials for protecting and delivering microbial inoculants for agricultural applications.


Assuntos
Nanocompostos , Nanopartículas , Carboximetilcelulose Sódica/química , Celulose/química , Hypocreales , Nanocompostos/química , Nanopartículas/química , Polímeros/química
15.
J Med Entomol ; 59(5): 1687-1693, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-35794805

RESUMO

Entomopathogenic fungi allow chemical-free and environmentally safe vector management. Beauveria bassiana (Balsamo-Crivelli) Vuillemin is a promising biological control agent and an important component of integrated vector management. We investigated the mortality of Aedes albopictus (Skuse) larvae exposed to five concentrations of B. bassiana using Mycotrol ESO and adult oviposition behavior to analyze the egg-laying preferences of wild Ae. albopictus in response to different fungal concentrations. We examined the mortality of mid-instars exposed to B. bassiana concentrations of 1 × 104, 1 × 105, 1 × 106, 1 × 107, and 1 × 108 conidia/ml every 24 h for 12 d. In the oviposition behavior study, the fungus was applied to wooden paddles at 1 × 105, 1 × 107, and 1 × 109 conidia/ml, and the paddles were individually placed into quad-ovitraps. Both experiments contained control groups without B. bassiana. Kaplan-Meier survival analysis revealed that larval mortality was concentration dependent. The median lethal concentration was 2.43 × 105 conidia/ml on d 12. The median lethal time was 3.68 d at 1 × 106 conidia/ml. Oviposition monitoring revealed no significant difference in egg count between the control and treatment paddles. We observed an inverse relationship between the concentration of B. bassiana and the percentage of paddles with eggs. We concluded that concentrations above 1 × 106 conidia/ml are larvicidal, and Ae. albopictus laid similar numbers of eggs on fungus-impregnated and control wooden substrates; however, they were more likely to oviposit on substrates without B. bassiana. With these findings, we suggest that B. bassiana-infused ovitraps can be used for mosquito population monitoring while also delivering mycopesticides to adult mosquitoes.


Assuntos
Aedes , Beauveria , Hypocreales , Aedes/fisiologia , Animais , Beauveria/fisiologia , Feminino , Larva/microbiologia , Mosquitos Vetores , Oviposição , Controle Biológico de Vetores , Esporos Fúngicos
16.
Environ Pollut ; 310: 119726, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35810983

RESUMO

It is estimated that over 700,000 tons of synthetic dyes are produced annually, 15% of which are emitted as effluents. These highly stable dyes enter the world water ecosystems and stay in the environment, and eventually cause adverse impacts to the environment. Current wastewater treatment methods, such as filtration, coagulation, and chemical oxidation, have sideeffects, including toxic residue formation, membrane fouling, bioaccumulation, and secondary pollutant formation. Given the issues mentioned, it is necessary to study how to improve the degradation of synthetic dye with a cost-effective and ecofriendly approach. Natural oxidation provides a greener option. Recently, Deuteromycetes fungus Myrothecium verrucaria G-1 (M. verrucaria G-1) has shown great potential in producing high level of dye oxidase. This study aims to generate a dye oxidase hyperproducer, 3H6 from M. verrucaria G-1 by using atmospheric and room temperature plasma (ARTP) coupled with ultraviolet (UV) irradiation. This method increases oxidase production by nearly 106.15%. After a simple precipitation and dialysis, this mutant oxidase increases by 1.97-fold in a specific activity with dye degradation rates at 70% for Mmethylene blue (MB) and 85% for Congo red (CR). It is found that the genetic stability of 3H6 remains active for ten generations. The size of oxidase is 65 kDa, and optimum temperature for reaction is 30 °C with 4.5 pH. This study presents that the first combined mutagenesis approach by ARPT-UV on fungus species generates an impressive increment of acid dye oxidases production. As such, this method presents a cost-effective alternative to mitigate hazardous dye pollution.


Assuntos
Hypocreales , Fungos Mitospóricos , Poluentes Químicos da Água , Corantes , Ecossistema , Mutagênese , Oxirredutases
17.
J Microbiol Methods ; 200: 106535, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35798135

RESUMO

The genus Trichoderma is ubiquitous in various niches and is currently used for biocontrol, biofertilizer, enzyme production and bioremediation. However, molecular mechanisms underlying its diverse biological functions are yet not fully elucidated. Extraction of high-quality RNA for downstream applications such as quantitative polymerase chain reaction is a prerequisite. The current study aims to optimize a total RNA extraction protocol for high-quality and quantity RNA from Trichoderma atrobrunneum. Seven RNA extraction protocols including Trizol, RiboEx PureLink RNA mini kit, high salt CTAB (cetyltrimethylammonium bromide), modified high salt CTAB, SDS (sodium dodecyl sulfate) and CTAB-PVP (polyvinylpyrrolidone) were performed separately, to extract RNA. Quality and quantity of extracted RNA samples were further analyzed by Nanodrop spectrophotometry, agarose gel electrophoresis and RT-PCR analysis. The results of quantitative and qualitative analysis of RNA samples showed that more intact, high-quality RNA was extracted using the modified high salt CTAB as compared to other methods. The RT-PCR results for the amplification of the genes encoding ß-tubulin and Ubiquitin carrier protein also showed lowest threshold cycle (Ct) and coefficient of variation (CV) for RNA samples extracted with the modified high salt CTAB method as compared to RNA samples extracted with other protocols. Therefore, it is proposed that the modified high salt CTAB protocol is an excellent method to obtain high-quality RNA with good yield from T. atrobrunneum for its downstream applications. Moreover, the optimized protocol is very economical and can be used to extract total RNA from a large number of samples.


Assuntos
RNA , Cetrimônio , Eletroforese em Gel de Ágar , Hypocreales , Reação em Cadeia da Polimerase Via Transcriptase Reversa
18.
Microbiol Spectr ; 10(4): e0087222, 2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-35852347

RESUMO

The expression of cellulase genes in lignocellulose-degrading fungus Trichoderma reesei is induced by insoluble cellulose and its soluble derivatives. Membrane-localized transporter/transceptor proteins have been thought to be involved in nutrient uptake and/or sensing to initiate the subsequent signal transduction during cellulase gene induction. Crt1 is a sugar transporter proven to be essential for cellulase gene induction although the detailed mechanism of Crt1-triggered cellulase induction remains elusive. In this study, we focused on the C-terminus region of Crt1 which is predicted to exist as an unstructured cytoplasmic tail in T. reesei. Serial C-terminal truncation of Crt1 revealed that deleting the last half of the C-terminal region of Crt1 hardly affected its transporting activity or ability to mediate the induction of cellulase gene expression. In contrast, removal of the entire C-terminus region eliminated both activities. Of note, Crt1-C5, retaining only the first five amino acids of C-terminus, was found to be capable of transporting lactose but failed to restore cellulase gene induction in the Δcrt1 strain. Analysis of the cellular localization of Crt1 showed that Crt1 existed both at the plasma membrane and at the periphery of the nucleus although the functional relevance is not clear at present. Finally, we showed that the cellulase production defect of Δcrt1 was corrected by overexpressing Xyr1, indicating that Xyr1 is a potential regulatory target of the signaling cascade initiated from Crt1. IMPORTANCE The lignocellulose-degrading fungus T. reesei has been widely used in industrial cellulases production. Understanding the precise cellulase gene regulatory network is critical for its genetic engineering to enhance the mass production of cellulases. As the key membrane protein involved in cellulase expression in T. reesei, the detailed mechanism of Crt1 in mediating cellulase induction remains to be investigated. In this study, the C-terminal region of Crt1 was found to be vital for its transport and signaling receptor functions. These two functions are, however, separable because a C-terminal truncation mutant is capable of sugar transporting but loses the ability to mediate cellulase gene expression. Furthermore, the key transcriptional activator Xyr1 represents a downstream target of the Crt1-initiated signaling cascade. Together, our research provides new insights into the function of Crt1 and further contributes to the unveiling of the intricate signal transduction process leading to efficient cellulase gene expression in T. reesei.


Assuntos
Celulase , Celulases , Trichoderma , Celulase/genética , Celulase/metabolismo , Celulases/genética , Celulases/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica , Hypocreales , Açúcares/metabolismo , Trichoderma/genética , Trichoderma/metabolismo
20.
Microb Cell Fact ; 21(1): 144, 2022 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-35842666

RESUMO

BACKGROUND: Filamentous fungi are highly efficient at deconstructing plant biomass by secreting a variety of enzymes, but the complex enzymatic regulation underlying this process is not conserved and remains unclear. RESULTS: In this study, cellulases and xylanases could specifically respond to Avicel- and xylan-induction, respectively, in lignocellulose-degrading strain Trichoderma guizhouense NJAU4742, however, the differentially regulated cellulases and xylanases were both under the absolute control of the same TgXyr1-mediated pathway. Further analysis showed that Avicel could specifically induce cellulase expression, which supported the existence of an unknown specific regulator of cellulases in strain NJAU4742. The xylanase secretion is very complex, GH10 endoxylanases could only be induced by Avicel, while, other major xylanases were significantly induced by both Avicel and xylan. For GH10 xylanases, an unknown specific regulator was also deduced to exist. Meanwhile, the post-transcriptional inhibition was subsequently suggested to stop the Avicel-induced xylanases secretion, which explained the specifically high xylanase activities when induced by xylan in strain NJAU4742. Additionally, an economical strategy used by strain NJAU4742 was proposed to sense the environmental lignocellulose under the carbon starvation condition, that only slightly activating 4 lignocellulose-degrading genes before largely secreting all 33 TgXyr1-controlled lignocellulases if confirming the existence of lignocellulose components. CONCLUSIONS: This study, aiming to explore the unknown mechanisms of plant biomass-degrading enzymes regulation through the combined omics analysis, will open directions for in-depth understanding the complex carbon utilization in filamentous fungi.


Assuntos
Celulases , Hypocreales , Trichoderma , Carbono/metabolismo , Celulases/genética , Celulases/metabolismo , Celulose/metabolismo , Hypocreales/genética , Hypocreales/metabolismo , Trichoderma/genética , Trichoderma/metabolismo , Xilanos/metabolismo
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