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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.
Int J Mol Sci ; 23(21)2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-36361917

RESUMO

Trichoderma spp. are an important plant-growth-promoting fungi. Trichoderma citrinoviride HT-1 was isolated from Rheum palmatum root, which has beneficial effects on growth and metabolite accumulation. However, the improvement mechanisms for growth and metabolite accumulation of T. citrinoviride HT-1 are unclear. In this study, RNA sequencing (RNA-seq) and high-performance liquid chromatography (HPLC) were used to measure the effect of different concentrations of conidial suspension of the HT-1 strain on the growth promotion and metabolite accumulation of R. palmatum seedlings. The results showed that the highest biomass and metabolites of R. palmatum seedlings were obtained through treatment with the HT-1 strain at a final spore concentration of 107 spores/mL. RNA sequencing indicated that 1662 genes were upregulated and 2155 genes were downregulated after inoculation with 107 spores/mL of the HT-1 strain. This strain induced significant upregulation of related genes in the phenylpropanoid biosynthesis pathway, plant hormone signal transduction pathway, biosynthesis of secondary metabolites pathway, and plant-pathogen interaction pathway in R. palmatum. The gene expression trends were revealed through quantitative real-time polymerase chain reaction (qRT-PCR) and were consistent with those determined by RNA-seq. Our results will help us to understand the growth-promoting mechanisms of the HT-1 strain on R. palmatum and provide a theoretical basis for the application of T. citrinoviride HT-1 as a biological fertilizer.


Assuntos
Hypocreales , Rheum , Trichoderma , Rheum/química , Cromatografia Líquida de Alta Pressão , Trichoderma/metabolismo , Plântula
3.
J Infect Dev Ctries ; 16(10): 1668-1670, 2022 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-36332225

RESUMO

Parengyodontium album is a very rarely encountered opportunistic fungal pathogen. A severely neutropenic 11-year-old boy with acute T-cell lymphoblastic leukemia/lymphoma was febrile and lethargic during his admission for elective chemotherapy. No cutaneous lesion or obvious source of infection was noted, and clinical examination was otherwise unremarkable. A blood specimen was sent for culture and fungal elements were visualized. Amphotericin B was administered empirically while awaiting fungal identification. Morphologically, a hyaline mould with thin septate hyphae plus smooth-walled conidiophores and conidiogenous cells arranged in whorls of up to four was cultured. Internal transcribed spacer region sequencing identified the fungus conclusively as P. album. Repeat blood culture was also positive for the same fungus. Following a two-week course of amphotericin B, fungemia clearance was attained.


Assuntos
Anfotericina B , Hypocreales , Masculino , Humanos , Criança , Anfotericina B/uso terapêutico , Antifúngicos/uso terapêutico , Malásia
4.
Mar Drugs ; 20(11)2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36355024

RESUMO

The biocontrol fungus Trichoderma harzianum, from both marine and terrestrial environments, has attracted considerable attention. T. harzianum has a tremendous potential to produce a variety of bioactive secondary metabolites (SMs), which are an important source of new herbicides and antibiotics. This review prioritizes the SMs of T. harzianum from 1988 to June 2022, and their relevant biological activities. Marine-derived SMs, especially terpenoids, polyketides, and macrolides compounds, occupy a significant proportion of natural products from T. harzianum, deserving more of our attention.


Assuntos
Hypocreales , Trichoderma , Trichoderma/metabolismo
5.
Int J Mol Sci ; 23(19)2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36232357

RESUMO

Ustilaginoidea virens (teleomorph: Villosiclava virens) is an important fungal pathogen that causes a devastating rice disease. It can produce mycotoxins including sorbicillinoids. The biosynthesis and biological functions of sorbicillinoids have not been reported in U. virens. In this study, we identified a sorbicillinoid biosynthetic gene cluster in which two polyketide synthase genes UvSorA and UvSorB were responsible for sorbicillinoid biosynthesis in U. virens. In ∆UvSorA and ∆UvSorB mutants, the mycelial growth, sporulation and hyphal hydrophobicity were increased dramatically, while the resistances to osmotic pressure, metal cations, and fungicides were reduced. Both phytotoxic activity of rice germinated seeds and cell wall integrity were also reduced. Furthermore, mycelia and cell walls of ∆UvSorA and ∆UvSorB mutants showed alterations of microscopic and submicroscopic structures. In addition, feeding experiment showed that sorbicillinoids could restore mycelial growth, sporulation, and cell wall integrity in ∆UvSorA and ∆UvSorB mutants. The results demonstrated that both UvSorA and UvSorB were responsible for sorbicillinoid biosynthesis in U. virens, and contributed to development (mycelial growth, sporulation, and cell wall integrity), stress responses, and phytotoxicity through sorbicillinoid mediation. It provides an insight into further investigation of biological functions and biosynthesis of sorbicillinoids.


Assuntos
Fungicidas Industriais , Hypocreales , Micotoxinas , Oryza , Fungicidas Industriais/farmacologia , Hypocreales/genética , Oryza/microbiologia , Doenças das Plantas/microbiologia , Policetídeo Sintases/genética
6.
Microb Genom ; 8(10)2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36239595

RESUMO

The ability to respond to injury is essential for the survival of an organism and involves analogous mechanisms in animals and plants. Such mechanisms integrate coordinated genetic and metabolic reprogramming events requiring regulation by small RNAs for adequate healing of the wounded area. We have previously reported that the response to injury of the filamentous fungus Trichoderma atroviride involves molecular mechanisms closely resembling those of plants and animals that lead to the formation of new hyphae (regeneration) and the development of asexual reproduction structures (conidiophores). However, the involvement of microRNAs in this process has not been investigated in fungi. In this work, we explore the participation of microRNA-like RNAs (milRNAs) molecules by sequencing messenger and small RNAs during the injury response of the WT strain and RNAi mutants. We found that Dcr2 appears to play an important role in hyphal regeneration and is required to produce the majority of sRNAs in T. atroviride. We also determined that the three main milRNAs produced via Dcr2 are induced during the damage-triggered developmental process. Importantly, elimination of a single milRNA phenocopied the main defects observed in the dcr2 mutant. Our results demonstrate the essential role of milRNAs in hyphal regeneration and asexual development by post-transcriptionally regulating cellular signalling processes involving phosphorylation events. These observations allow us to conclude that fungi, like plants and animals, in response to damage activate fine-tuning regulatory mechanisms.


Assuntos
Hypocreales , MicroRNAs , Animais , Regulação Fúngica da Expressão Gênica , Hifas/genética , Hypocreales/genética , Hypocreales/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Regeneração/genética
7.
Biocontrol Sci ; 27(3): 117-130, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36216563

RESUMO

Purpureocillium lilacinum has been recently found to contaminate a 20% (200,000 µg/mL) aqueous solution of polyhexamethylene biguanide hydrochloride (PHMB) . We aimed to elucidate the mechanism underlying the resistance of P. lilacinum to PHMB. First, we induced the PHMB-resistant (IR) strains IFM 67050 (IR) and IFM 65838 (IR) from the type strain P. lilacinum CBS 284.36T via cultivation in a medium containing high concentrations of PHMB. We then analyzed the DNA sequences via Illumina sequencing to evaluate the presence of genetic mutations in IFM 65838 (IR) . Further, we established an IFM 65838 (IR) uridine/uracil auxotrophic strain, and using the orotidine-5'-decarboxylase gene, pyrG as a selection marker, we tried to knockout a mutant gene in IFM 65838 (IR) using the CRISPR-Cas9 genome-editing technique. The growth rates of IFM 67050 (IR) and IFM 65838 (IR) in medium containing PHMB increased, and the minimum inhibitory concentrations (MICs) against PHMB also increased. Based on the DNA sequence analysis, we found a nonsynonymous point mutation in the gene PLI-008146 (G779A) in IFM 67050 (IR) and IFM 65838 (IR) . This point mutation leads to site combinations of splicing changes that cause partial sequences deletion (p.Y251_G281del) in the ΔPLI-008146 locus of IFM 65838 (IR) , and deletion sequences include partial adenosine/AMP deaminase motif (PF00962) orthologous to adenosine deaminase (ADA) (GeneBank: OAQ82383.1) . Furthermore, the mutant gene ΔPLI-008146 was successfully knocked out from the resistanceinduced strain using a novel CRISPR-Cas9 gene transformation method. A considerable reduction in growth rate and MIC against PHMB was observed in the absence of the mutant gene. Therefore, ADA may represent an important resistance factor in PHMB-resistant P. lilacinum.


Assuntos
AMP Desaminase , Carboxiliases , Adenosina , Adenosina Desaminase , Biguanidas/farmacologia , Hypocreales , Uracila , Uridina
8.
Chemosphere ; 308(Pt 3): 136567, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36152826

RESUMO

5-Hydroxymethylfurfural (HMF) is a fermentation inhibitor which is formed during acid-based thermochemical pre-treatment of biomass. The present study involves two approaches for HMF conversion; the first includes screening and identification of fungal strains which produce oxidoreductases for HMF bioconversion, and thereafter evaluating their roles in HMF conversion. Out of the ten fungal strains screened, genetically engineered Trichoderma atroviride (Lac+) showed maximum HMF bioconversion and the activities of ligninolytic enzymes produced were noted. Maximum HMF conversion of 99% was achieved at pH 5.0 and 30 °C when 72 h old 10% inoculum of T. atroviride (Lac+) was utilized for 6 days. Based on the fungal bioconversion of HMF to 2, 5 diformylfuran with 58% yield, laccase was observed to influence the conversion process. Thus, a comparative study was established on HMF conversion by 100 U/mL of commercial laccases and partially purified laccase from T. atroviride (Lac+). In the presence of TEMPO, T. atroviride laccase showed comparable HMF conversion to commercial laccases, which establishes the efficiency of fungi and ligninolytic enzymes in bioconversion of HMF to value-added products.


Assuntos
Hypocreales , Trichoderma , Biomassa , Furaldeído/análogos & derivados , Lacase
9.
J Org Chem ; 87(21): 14058-14067, 2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-36162105

RESUMO

Two highly oxygenated pentacyclic polyketides with two new carbon skeletons, trichopsistide A (1) and trichopsistide B (2), were isolated from the plant endophyte Trichoderma koningiopsis WZ-196 derived from the leaf of Rubia podantha Diels. The structures of these polyketides with full configurations were determined by comprehensive spectroscopic analysis, computer-assisted structure elucidation software, computational calculation, and X-ray crystal diffraction. Among them, 1 represented the first example of an unprecedented 5/6/6/6/5 pentacyclic ketal-containing polyketide pyridine alkaloid, and 2 possessed a novel 6/6/6/6/5 pentacyclic ketal-containing polyketide scaffold fused with an α-pyrone. The plausible biosynthetic route for 1 and 2 was also proposed. Moreover, biological activity assays showed that 1 and 2 possessed inhibitory effects on the NF-κB signaling pathway with IC50 values of 14.77 and 8.58 µM, respectively. Furthermore, 1 and 2 could also inhibit the expression of IκBα and p65 phosphorylation, decrease the expression of MCP-1, E-selectin, and IL-8 at the mRNA level, and inhibit the TNF-α-induced nuclear translocation of p65.


Assuntos
Hypocreales , Policetídeos , NF-kappa B/metabolismo , Policetídeos/química , Estrutura Molecular , Hypocreales/metabolismo , Transdução de Sinais
10.
Braz J Microbiol ; 53(4): 1871-1880, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36173601

RESUMO

Microencapsulation of microorganisms has been studied to increase product shelf life and stability to enable the application in sustainable agriculture. In this study, the microencapsulation of Trichoderma asperellum conidia by spray drying (SD) was evaluated. The objective was to assess the effect of drying air temperature and wall material (maltodextrin DE20, MD20) concentration on the microencapsulation and to identify the optimum conditions to produce, in high yield, microparticles with low moisture, high conidial viability and conidial survival. Microparticles were characterized in terms of morphology, particle size, and shelf life. A central composite rotatable design (CCRD) was used to evaluate the effect of operating parameters on drying yield (DY), moisture content, conidial viability (CV), and conidial survival (SP). Microencapsulation experiments were carried out under optimum conditions to validate the obtained model. The optimum temperature and MD20/conidia dry weight ratios were 80 °C and 1:4.5, respectively, which afforded a drying yield of 63.85 ± 0.86%, moisture content of 4.92 ± 0.07%, conidial viability of 87.10 ± 1.16%, and conidial survival of 85.78 ± 2.88%. Microencapsulation by spray drying using MD20 as wall material extended the viability of conidia stored at 29 °C compared with the control. The mathematical models accurately predicted all the variables studied, and the association of the microencapsulation technique using DE20 maltodextrin was able to optimize the process and increase the product's shelf life. It was also concluded that high inlet air temperatures negatively affected conidia survival, especially above 100 °C.


Assuntos
Hypocreales , Secagem por Atomização , Esporos Fúngicos , Dessecação
11.
J Invertebr Pathol ; 194: 107826, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36075444

RESUMO

The yellow peach moth (YPM), Conogethes punctiferalis, is a destructive insect pest of maize in eastern China and adapts to diverse environments, especially against pathogens. In insects, innate immunity comprising both humoral and cellular defense responses, is the primary defense against invading microbial pathogens. In this study, we identified five types of circulating hemocytes from the hemolymph of YPM larvae and analyzed their alterations and functions in immune responses to the infection of Beauveria bassiana, an entomopathogenic fungus infesting many lepidopteran species. The identified hemocytes included prohemocytes, plasmatocytes, granulocytes, spherulocytes and oenocytoids. Significant decreases of total and differential hemocyte counts were recorded over time in larvae, after they were injected with B. bassiana conidia. Additionally, hemocyte-mediated phagocytosis and nodulation were initiated in the hemolymph of larvae from the B. bassiana conidia challenge. The introduction of DEAE-Sepharose Fast Flow beads stained with Congo red also induced a strong encapsulation response in the larval hemolymph. Our observations unravel the occurrence of phagocytosis, nodulation and encapsulation in the hemocoel of YPM larvae to fight against the fungal infection, and offer the first insight into the YPM immune system.


Assuntos
Beauveria , Hypocreales , Mariposas , Animais , Beauveria/fisiologia , Vermelho Congo , Hemócitos , Imunidade Celular , Larva/microbiologia , Mariposas/microbiologia , Sefarose , Esporos Fúngicos
12.
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
13.
Microbiol Res ; 265: 127182, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36116145

RESUMO

This study investigated the biocontrol ability of Trichoderma harzianum CGMCC20739 (Tha739) against apple bitter rot caused by Colletotrichum gloeosporioides. In vitro tests, Tha739 inhibited the mycelial growth of C. gloeosporioides. Microscopic observation showed that Tha739 grew in parallel with, coiled around, and deformed the hyphae of C. gloeosporioides. Tha739-derived metabolites decreased the conidia production of C. gloeosporioides. In vivo tests, the lesion diameters of wounded apples treated with Tha739 1 h before C. gloeosporioides were lower than those of wounded apples treated with Tha739 after pathogen inoculation. In addition, compared with the apples inoculated with C. gloeosporioides only, the disease index of unwounded apples inoculated with Tha739 and C. gloeosporioides decreased by 2.17-fold. Furthermore, compared with the control, the total soluble solid contents of apples treated with Tha739 were 9.02 % and 1.54 % higher at 1 and 3 d, respectively. The titratable acidity contents of apples treated with Tha739 were 10.02 % and 14.58 % higher than those in the control at 1 and 3 d after treatment, respectively. The soluble sugar content and weight loss in Tha739 treatment group and control were not significantly different. The results showed that Tha739 could control apple bitter rot and maintain the nutritional quality of the fruit. Thus, T. harzianum Tha739 is a potentially biocontrol agent for harvested apples.


Assuntos
Hypocreales , Malus , Frutas , Açúcares
14.
Microbiol Spectr ; 10(5): e0197522, 2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-36094103

RESUMO

Tiankeng acts as a refugium for biodiversity amid a changing global climate, and a previous study has shown that some ancient (Alsophila spinulosa) and unique plants (cool-adapted plants) are present in Tiankeng. However, there are few reports on Ascomycota from the Tiankeng karst region. In this research, the species diversity of Cordyceps-like fungi in Monkey-Ear Tiankeng was investigated. Seven species in the genera Akanthomyces, Beauveria, Cordyceps, and Samsoniella were identified based on internal transcribed spacer sequences and morphological characteristics. Eight new species in the genera Akanthomyces, Cordyceps, and Samsoniella were established and described according to a multilocus phylogenetic analysis and morphological characteristics. Our results revealed that Cordyceps-like fungi were abundant in Monkey-Ear Tiankeng, providing new insights into the diversity of Ascomycota in this special eco-environment. IMPORTANCE Karst Tiankeng has a special eco-environment and acts as a refugium for biodiversity. However, there are few reports on Ascomycota from the Tiankeng karst region. In this research, seven known species and eight new species in the genera Akanthomyces, Beauveria, Cordyceps, and Samsoniella were reported. The results showed that Cordyceps-like fungi are abundant in Monkey-Ear Tiankeng. Interestingly, the month of the sampling was November, which is not an active period of growth and reproduction for Cordyceps-like fungi. These results revealed that unconventional time sampling should not be ignored, especially for a special eco-environment, and provided new insights into the diversity of Ascomycota in this special eco-environment.


Assuntos
Cordyceps , Hypocreales , Animais , Cordyceps/genética , Filogenia , China , Biodiversidade , Hypocreales/genética , Haplorrinos , Fungos/genética
15.
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
16.
Int J Mol Sci ; 23(18)2022 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-36142214

RESUMO

Antimicrobial peptides (AMPs) serve as alternative candidates for antibiotics and have attracted the attention of a wide range of industries for various purposes, including the prevention and treatment of piglet diarrhea in the swine industry. Escherichia coli, Salmonella, and Clostridium perfringens are the most common pathogens causing piglet diarrhea. In this study, the antimicrobial peptide gloverin2 (BMGlv2), derived from Bombyx mandarina, was explored to determine the efficient prevention effect on bacterial piglet diarrhea. BMGlv2 was heterologously expressed in Trichoderma reesei Tu6, and its antimicrobial properties against the three bacteria were characterized. The results showed that the minimum inhibitory concentrations of the peptide against E. coli ATCC 25922, S. derby ATCC 13076, and C. perfringens CVCC 2032 were 43.75, 43.75, and 21.86 µg/mL, respectively. The antimicrobial activity of BMGlv2 was not severely affected by high temperature, salt ions, and digestive enzymes. It had low hemolytic activity against rabbit red blood cells, indicating its safety for use as a feed additive. Furthermore, the measurements of the leakage of bacterial cell contents and scanning electron microscopy of C. perfringens CVCC 2032 indicated that BMGlv2 exerted antimicrobial activity by destroying the cell membrane. Overall, this study showed the heterologous expression of the antimicrobial peptide BMGlv2 in T. reesei and verified its antimicrobial properties against three common pathogenic bacteria associated with piglet diarrhea, which can provide a reference for the applications of AMPs as an alternative product in industrial agriculture.


Assuntos
Anti-Infecciosos , Trichoderma , Animais , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Peptídeos Antimicrobianos , Bactérias/metabolismo , Clostridium perfringens/metabolismo , Diarreia , Escherichia coli/genética , Escherichia coli/metabolismo , Hypocreales , Coelhos , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacologia , Suínos , Trichoderma/metabolismo
17.
Int J Mol Sci ; 23(18)2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-36142440

RESUMO

Rice false smut caused by the biotrophic fungal pathogen Ustilaginoidea virens has become one of the most important diseases in rice. The large effector repertory in U. virens plays a crucial role in virulence. However, current knowledge of molecular mechanisms how U. virens effectors target rice immune signaling to promote infection is very limited. In this study, we identified and characterized an essential virulence effector, SCRE4 (Secreted Cysteine-Rich Effector 4), in U. virens. SCRE4 was confirmed as a secreted nuclear effector through yeast secretion, translocation assays and protein subcellular localization, as well as up-regulation during infection. The SCRE4 gene deletion attenuated the virulence of U. virens to rice. Consistently, ectopic expression of SCRE4 in rice inhibited chitin-triggered immunity and enhanced susceptibility to false smut, substantiating that SCRE4 is an essential virulence factor. Furthermore, SCRE4 transcriptionally suppressed the expression of OsARF17, an auxin response factor in rice, which positively regulates rice immune responses and resistance against U. virens. Additionally, the immunosuppressive capacity of SCRE4 depended on its nuclear localization. Therefore, we uncovered a virulence strategy in U. virens that transcriptionally suppresses the expression of the immune positive modulator OsARF17 through nucleus-localized effector SCRE4 to facilitate infection.


Assuntos
Hypocreales , Oryza , Quitina/metabolismo , Cisteína/metabolismo , Hypocreales/metabolismo , Ácidos Indolacéticos/metabolismo , Oryza/genética , Oryza/microbiologia , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Fatores de Virulência/metabolismo
18.
Plant Physiol Biochem ; 190: 184-192, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36126463

RESUMO

The use of growth-promoting microorganisms with biostimulant characteristics is an important biological asset for the acclimatization of micropropagated seedlings. The present study aimed to evaluate the efficacy of the application of Trichoderma spp. on the promotion of the growth of micropropagated banana seedlings during acclimatization. The experiment was performed in an 8 × 6 completely randomized design using the following treatments: water, seedlings fertilized with controlled-release fertilizer, commercial biological inputs (A: T. asperellum, B/C: T. harzianum), and LPPC299 and LPPC300 strains. Plant height, pseudostem diameter, number of leaves, total leaf area, root length, fresh and dry mass of the plant, and accumulation of sodium, macronutrients, and micronutrients were evaluated 60 days after inoculation. Strains LPPC299 and LPPC300 were subjected to molecular identification by DNA sequencing of the ITS/5.8S locus. In vitro detection of growth promotion-related mechanisms and mycelial growth of biostimulants were performed using scanning electron microscopy. LPPC299 and LPPC300 had a greater similarity to T. longibrachiatum. LPPC299 was able to promote greater pseudostem diameter, number of leaves, and total leaf area in banana seedlings. T. asperellum (A) favored seedling performance in terms of fresh and dry mass of the plants. The strains were able to produce siderophores, indoleacetic acid, and catalase in vitro. Seedlings inoculated with the strains accumulated Mn, S (LPPC300), and Mg (LPPC299). LPPC299 from the banana rhizosphere was efficient in promoting performance in banana seedlings, showing its potential as a biostimulant for this crop.


Assuntos
Musa , Trichoderma , Aclimatação , Catalase , Preparações de Ação Retardada , Fertilizantes , Hypocreales , Micronutrientes , Raízes de Plantas , Plântula , Sideróforos , Sódio , Água
19.
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
20.
Microb Biotechnol ; 15(10): 2533-2546, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35921310

RESUMO

Sorbicillinoids (also termed yellow pigment) are derived from either marine or terrestrial fungi, exhibit various biological activities and therefore show potential as commercial products for human or animal health. The cellulolytic filamentous fungus Trichoderma reesei is capable to biosynthesize sorbicillinoids, but the underlying regulatory mechanism is not yet completely clear. Herein, we identified a histone H3 lysine 9 (H3K9) methyltransferase, Dim5, in T. reesei. TrDIM5 deletion caused an impaired vegetative growth as well as conidiation, whereas the ∆Trdim5 strain displayed a remarkable increase in sorbicillinoid production. Post TrDIM5 deletion, the transcription of sorbicillinoid biosynthesis-related (SOR) genes was significantly upregulated with a more open chromatin structure. Intriguingly, hardly any expression changes occurred amongst those genes located on both flanks of the SOR gene cluster. In addition, the assays provided evidence that H3K9 triple methylation (H3K9me3) modification acted as a repressive marker at the SOR gene cluster and thus directly mediated the repression of sorbicillinoid biosynthesis. Transcription factor Ypr1 activated the SOR gene cluster by antagonizing TrDim5-mediated repression and therefore contributed to forming a relatively more open local chromatin environment, which further facilitated its binding and SOR gene expression. The results of this study will contribute to understanding the intricate regulatory network in sorbicillinoid biosynthesis and facilitate the endowment of T. reesei with preferred features for sorbicillinoid production by genetic engineering.


Assuntos
Trichoderma , Cromatina/metabolismo , Histona Metiltransferases/genética , Histona Metiltransferases/metabolismo , Histonas/genética , Histonas/metabolismo , Humanos , Hypocreales , Lisina/genética , Lisina/metabolismo , Fatores de Transcrição/metabolismo , Trichoderma/genética , Trichoderma/metabolismo
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