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1.
Microbes Environ ; 39(2)2024.
Artigo em Inglês | MEDLINE | ID: mdl-38866480

RESUMO

Mn(II)-oxidizing microorganisms are considered to play significant roles in the natural geochemical cycles of Mn and other heavy metals because the insoluble biogenic Mn oxides (BMOs) that are produced by these microorganisms adsorb other dissolved heavy metals and immobilize them as precipitates. In the present study, a new Mn(II)-oxidizing fungal strain belonging to the ascomycete genus Periconia, a well-studied plant-associating fungal genus with Mn(II)-oxidizing activity that has not yet been exami-ned in detail, was isolated from natural groundwater outflow sediment. This isolate, named strain TS-2, was confirmed to oxidize dissolved Mn(II) and produce insoluble BMOs that formed characteristic, separately-located nodules on their hyphae while leaving major areas of the hyphae free from encrustation. These BMO nodules also adsorbed and immobilized dissolved Cu(II), a model analyte of heavy metals, as evidenced by elemental mapping ana-lyses of fungal hyphae-BMO assemblages using a scanning electron microscope with energy-dispersive X-ray spectroscopy (SEM-EDX). Analyses of functional genes within the whole genome of strain TS-2 further revealed the presence of multiple genes predicted to encode laccases/multicopper oxidases that were potentially responsible for Mn(II) oxidation by this strain. The formation of BMO nodules may have functioned to prevent the complete encrustation of fungal hyphae, thereby enabling the control of heavy metal concentrations in their local microenvironments while maintaining hyphal functionality. The present results will expand our knowledge of the physiological and morphological traits of Mn(II)-oxidizing Periconia, which may affect the natural cycle of heavy metals through their immobilization.


Assuntos
Cobre , Hifas , Compostos de Manganês , Óxidos , Hifas/metabolismo , Hifas/crescimento & desenvolvimento , Cobre/metabolismo , Compostos de Manganês/metabolismo , Óxidos/metabolismo , Óxidos/química , Ascomicetos/genética , Ascomicetos/metabolismo , Ascomicetos/química , Oxirredução , Água Subterrânea/microbiologia , Água Subterrânea/química , Filogenia , Sedimentos Geológicos/microbiologia , Microscopia Eletrônica de Varredura , Manganês/metabolismo
2.
Fitoterapia ; 176: 106053, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38838828

RESUMO

Biotransformation of ursane-type triterpenoid ilexgenin A by endophytic fungi Lasiodiplodia sp. MQD-4 and Pestalotiopsis sp. ZZ-1, isolated from Ilex pubescences and Callicarpa kwangtungensis respectively, was investigated for the first time. Six previously undescribed metabolites (1-6) with 23-norursane triterpenoids skeleton were isolated and their structures were unambiguously established by the analysis of spectroscopic data and single-crystal X-ray crystallographic experiments. Decarboxylation, oxidation, and hydroxylation reactions were observed on the triterpenoid skeleton. Especially, the decarboxylation of C-23 provided definite evidence to understand the biogenetic process of 23-norursane triterpenoids. Moreover, the qualitative analysis of the extract of I. pubescences showed metabolites 1, 3, 4, and 6 could be detected in the originated plant, indicating biotransformation by endophytic fungi is a practical strategy for the isolation of novel natural products. Finally, all isolates were evaluated for the protective activities against H2O2-induced HUVECs dysfunction in vitro. Compound 5 could improve the viability of endothelial cells and decrease the level of intracellular ROS.


Assuntos
Biotransformação , Endófitos , Células Endoteliais da Veia Umbilical Humana , Ilex , Triterpenos , Triterpenos/isolamento & purificação , Triterpenos/farmacologia , Triterpenos/metabolismo , Endófitos/química , Endófitos/metabolismo , Estrutura Molecular , Humanos , Ilex/microbiologia , Ascomicetos/química , Ascomicetos/metabolismo , China
3.
Sci Rep ; 14(1): 13903, 2024 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-38886460

RESUMO

Rice straw breakdown is sluggish, which makes agricultural waste management difficult, however pretreatment procedures and cellulolytic fungi can address this issue. Through ITS sequencing, Chaetomium globosum C1, Aspergillus sp. F2, and Ascomycota sp. SM2 were identified from diverse sources. Ascomycota sp. SM2 exhibited the highest carboxymethyl cellulase (CMCase) activity (0.86 IU/mL) and filter-paper cellulase (FPase) activity (1.054 FPU/mL), while Aspergillus sp. F2 showed the highest CMCase activity (0.185 IU/mL) after various pretreatments of rice straw. These fungi thrived across a wide pH range, with Ascomycota sp. SM2 from pH 4 to 9, Aspergillus sp. F2, and Chaetomium globosum C1 thriving in alkaline conditions (pH 9). FTIR spectroscopy revealed significant structural changes in rice straw after enzymatic hydrolysis and solid-state fermentation, indicating lignin, cellulose, and hemicellulose degradation. Soil amendments with pretreated rice straw, cow manure, biochar, and these fungi increased root growth and soil nutrient availability, even under severe salt stress (up to 9.3 dS/m). The study emphasizes the need for a better understanding of Ascomycota sp. degradation capabilities and proposes that using cellulolytic fungus and pretreatment rice straw into soil amendments could mitigate salt-related difficulties and improve nutrient availability in salty soils.


Assuntos
Celulase , Oryza , Solo , Oryza/metabolismo , Solo/química , Celulase/metabolismo , Estresse Salino , Microbiologia do Solo , Celulose/metabolismo , Chaetomium/metabolismo , Aspergillus/metabolismo , Hidrólise , Concentração de Íons de Hidrogênio , Ascomicetos/metabolismo , Fermentação , Esterco/microbiologia , Carvão Vegetal
4.
Food Microbiol ; 122: 104557, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38839221

RESUMO

To investigate the potential antifungal mechanisms of rhizosphere Actinobacteria against Ceratocystis fimbriata in sweet potato, a comprehensive approach combining biochemical analyses and multi-omics techniques was employed in this study. A total of 163 bacterial strains were isolated from the rhizosphere soil of sweet potato. Among them, strain MEPS155, identified as Streptomyces djakartensis, exhibited robust and consistent inhibition of C. fimbriata mycelial growth in in vitro dual culture assays, attributed to both cell-free supernatant and volatile organic compounds. Moreover, strain MEPS155 demonstrated diverse plant growth-promoting attributes, including the production of indole-3-acetic acid, 1-aminocyclopropane-1-carboxylate deaminase, phosphorus solubilization, nitrogen fixation, and enzymatic activities such as cellulase, chitinase, and protease. Notably, strain MEPS155 exhibited efficacy against various sweet potato pathogenic fungi. Following the inoculation of strain MEPS155, a significant reduction (P < 0.05) in malondialdehyde content was observed in sweet potato slices, indicating a potential protective effect. The whole genome of MEPS155 was characterized by a size of 8,030,375 bp, encompassing 7234 coding DNA sequences and 32 secondary metabolite biosynthetic gene clusters. Transcriptomic analysis revealed 1869 differentially expressed genes in the treated group that cultured with C. fimbriata, notably influencing pathways associated with porphyrin metabolism, fatty acid biosynthesis, and biosynthesis of type II polyketide products. These alterations in gene expression are hypothesized to be linked to the production of secondary metabolites contributing to the inhibition of C. fimbriata. Metabolomic analysis identified 1469 potential differently accumulated metabolites (PDAMs) when comparing MEPS155 and the control group. The up-regulated PDAMs were predominantly associated with the biosynthesis of various secondary metabolites, including vanillin, myristic acid, and protocatechuic acid, suggesting potential inhibitory effects on plant pathogenic fungi. Our study underscores the ability of strain S. djakartensis MEPS155 to inhibit C. fimbriata growth through the production of secretory enzymes or secondary metabolites. The findings contribute to a theoretical foundation for future investigations into the role of MEPS155 in postharvest black rot prevention in sweet potato.


Assuntos
Ascomicetos , Ipomoea batatas , Doenças das Plantas , Rizosfera , Streptomyces , Ipomoea batatas/microbiologia , Streptomyces/genética , Streptomyces/metabolismo , Streptomyces/isolamento & purificação , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Ascomicetos/crescimento & desenvolvimento , Ascomicetos/metabolismo , Ascomicetos/genética , Microbiologia do Solo , Antifúngicos/farmacologia , Antifúngicos/metabolismo , Multiômica
5.
Food Microbiol ; 122: 104551, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38839219

RESUMO

Brown rot, caused by Monilinia fructicola, is considered one of the devasting diseases of pre-harvest and post-harvest peach fruits, restricting the yield and quality of peach fruits and causing great economic losses to the peach industry every year. Presently, the management of the disease relies heavily on chemical control. In the study, we demonstrated that the volatile organic compounds (VOCs) of endophyte bacterial Pseudomonas protegens QNF1 inhibited the mycelial growth of M. fructicola by 95.35% compared to the control, thereby reducing the brown rot on postharvest fruits by 98.76%. Additionally, QNF1 VOCs severely damaged the mycelia of M. fructicola. RNA-seq analysis revealed that QNF1 VOCs significantly repressed the expressions of most of the genes related to pathogenesis (GO:0009405) and integral component of plasma membrane (GO:0005887), and further analysis revealed that QNF1 VOCs significantly altered the expressions of the genes involved in various metabolism pathways including Amino acid metabolism, Carbohydrate metabolism, and Lipid metabolism. The findings of the study indicated that QNF1 VOCs displayed substantial control efficacy by disrupting the mycelial morphology of M. fructicola, weakening its pathogenesis, and causing its metabolic disorders. The study provided a potential way and theoretical support for the management of the brown rot of peach fruits.


Assuntos
Ascomicetos , Frutas , Doenças das Plantas , Prunus persica , Pseudomonas , Compostos Orgânicos Voláteis , Compostos Orgânicos Voláteis/farmacologia , Compostos Orgânicos Voláteis/metabolismo , Prunus persica/microbiologia , Frutas/microbiologia , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Pseudomonas/genética , Pseudomonas/metabolismo , Ascomicetos/genética , Ascomicetos/efeitos dos fármacos , Ascomicetos/crescimento & desenvolvimento , Ascomicetos/metabolismo , Micélio/crescimento & desenvolvimento , Micélio/efeitos dos fármacos , Micélio/genética , Endófitos/genética , Endófitos/metabolismo
6.
Arch Microbiol ; 206(6): 264, 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38760519

RESUMO

Fungi that inhabit fire-prone forests have to be adapted to harsh conditions and fungi affiliated to Ascomycota recovered from foliar litter samples were used for bioprospecting of molecules such as enzymes. Agni's fungi isolated from leaf litter, whose spores are capable of tolerating 110 oC were screened for thermostable lipases. One of the isolates, Leptosphaerulina trifolii A SMR-2011 exhibited high positive lipase activity than other isolates while screening through agar plate assay using Tween 20 in the medium. Maximum lipase activity (173.2 U/mg) of L. trifolii was observed at six days of inoculation and decreased thereafter. Among different oils used, the maximum lipase activity was attained by soybean oil (940.1 U/mg) followed by sunflower oil (917.1 U/mg), and then by mustard oil (884.8 U/mg), showing its specificity towards unsaturated fatty acids. Among the various organic nitrogen sources tested, soybean meal showed maximum lipase activity (985.4 U/mg). The partially purified enzyme was active over a wide range of pH from 8 to 12 with a pH optimum of 11.0 (728.1 U/mg) and a temperature range of 60-80 oC with an optimal temperature of 70 oC (779.1 U/mg). The results showed that lipase produced by L. trifolii is alkali stable and retained 85% of its activity at pH 11.0. This enzyme also showed high thermal stability retaining more than 50% of activity when incubated at 60 oC to 90 °C for 2 h. The ions Ca2+ and Mn2+ induced the lipase activity, while Cu2+ and Zn2+ ions lowered the activity compared to control. These results suggests that the leaf litter fungus L. trifolii serves as a potential source for the production of alkali-tolerant and thermostable lipase.


Assuntos
Ascomicetos , Estabilidade Enzimática , Proteínas Fúngicas , Lipase , Folhas de Planta , Lipase/metabolismo , Lipase/genética , Folhas de Planta/microbiologia , Ascomicetos/enzimologia , Ascomicetos/genética , Ascomicetos/metabolismo , Concentração de Íons de Hidrogênio , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Temperatura , Especificidade por Substrato , Temperatura Alta , Proteínas de Bactérias
7.
Appl Environ Microbiol ; 90(6): e0066524, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38814060

RESUMO

Ash dieback, caused by the fungal pathogen Hymenoscyphus fraxineus (Helotiales, Ascomycota), is threatening the existence of the European ash, Fraxineus excelsior. During our search for biological control agents for this devastating disease, endophytic fungi were isolated from healthy plant tissues and co-cultivated with H. fraxineus to assess their antagonistic potential. Among the strains screened, Penicillium cf. manginii DSM 104493 most strongly inhibited the pathogen. Initially, DSM 104493 showed promise in planta as a biocontrol agent. Inoculation of DSM 104493 into axenically cultured ash seedlings greatly decreased the development of disease symptoms in seedlings infected with H. fraxineus. The fungus was thus cultivated on a larger scale in order to obtain sufficient material to identify active metabolites that accounted for the antibiosis observed in dual culture. We isolated PF1140 (1) and identified it as the main active compound in the course of a bioassay-guided isolation strategy. Furthermore, its derivative 2, the mycotoxin citreoviridin (3), three tetramic acids of the vancouverone type (4-6), and penidiamide (7) were isolated by preparative chromatography. The structures were elucidated mainly by NMR spectroscopy and high-resolution mass spectrometry (HRMS), of which compounds 2 and 6 represent novel natural products. Of the compounds tested, not only PF1140 (1) strongly inhibited H. fraxineus in an agar diffusion assay but also showed phytotoxic effects in a leaf puncture assay. Unfortunately, both the latent virulent attributes of DSM 104493 observed subsequent to these experiments in planta and the production of mycotoxins exclude strain Penicillium cf. manginii DSM 104493 from further development as a safe biocontrol agent.IMPORTANCEEnvironmentally friendly measures are urgently needed to control the causative agent of ash dieback, Hymenoscyphus fraxineus. Herein, we show that the endophyte DSM 104493 exhibits protective effects in vitro and in planta. We traced the activity of DSM 104493 to the antifungal natural product PF1140, which unfortunately also showed phytotoxic effects. Our results have important implications for understanding plant-fungal interactions mediated by secondary metabolites, not only in the context of ash dieback but also generally in plant-microbial interactions.


Assuntos
Antifúngicos , Ascomicetos , Endófitos , Fraxinus , Doenças das Plantas , Fraxinus/microbiologia , Endófitos/metabolismo , Endófitos/isolamento & purificação , Ascomicetos/efeitos dos fármacos , Ascomicetos/metabolismo , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Antifúngicos/farmacologia , Antifúngicos/metabolismo , Antibiose , Metabolismo Secundário , Penicillium/metabolismo , Penicillium/efeitos dos fármacos , Agentes de Controle Biológico/farmacologia , Agentes de Controle Biológico/metabolismo
8.
Sci Rep ; 14(1): 10091, 2024 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-38698065

RESUMO

Eukaryotes produce a large number of cytochrome P450s that mediate the synthesis and degradation of diverse endogenous and exogenous metabolites. Yet, most of these P450s are uncharacterized and global tools to study these challenging, membrane-resident enzymes remain to be exploited. Here, we applied activity profiling of plant, mouse and fungal P450s with chemical probes that become reactive when oxidized by P450 enzymes. Identification by mass spectrometry revealed labeling of a wide range of active P450s, including six plant P450s, 40 mouse P450s and 13 P450s of the fungal wheat pathogen Zymoseptoria tritici. We next used transient expression of GFP-tagged P450s by agroinfiltration to show ER-targeting and NADPH-dependent, activity-based labeling of plant, mouse and fungal P450s. Both global profiling and transient expression can be used to detect a broad range of active P450s to study e.g. their regulation and discover selective inhibitors.


Assuntos
Sistema Enzimático do Citocromo P-450 , Proteínas Fúngicas , Proteoma , Animais , Sistema Enzimático do Citocromo P-450/metabolismo , Sistema Enzimático do Citocromo P-450/genética , Camundongos , Proteoma/metabolismo , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Ascomicetos/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética
9.
Nat Commun ; 15(1): 4357, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38821954

RESUMO

Triazoles are widely used to control pathogenic fungi. They inhibit the ergosterol biosynthetic pathway, but the precise mechanisms leading to fungicidal activities in many fungal pathogens are poorly understood. Here, we elucidate the mode of action of epoxiconazole and metconazole in the wheat pathogen Zymoseptoria tritici and the rice blast fungus Magnaporthe oryzae. We show that both azoles have fungicidal activity and reduce fluidity, but not integrity, of the plasma membrane. This impairs localisation of Cdc15-like F-BAR proteins, resulting in defective actin ring assembly and incomplete septation. However, mutant studies and pharmacological experiments in vitro and in planta show that azole lethality is due to a combination of reactive oxygen species-induced apoptosis and macroautophagy. Simultaneous inhibition of both programmed cell death pathways abolishes azole-induced cell death. Other classes of ergosterol biosynthesis inhibitors also induce apoptosis and macroautophagy, suggesting that activation of these two cell death pathways is a hallmark of ergosterol synthesis-targeting fungicides. This knowledge will inform future crop protection strategies.


Assuntos
Apoptose , Ascomicetos , Fungicidas Industriais , Doenças das Plantas , Espécies Reativas de Oxigênio , Apoptose/efeitos dos fármacos , Doenças das Plantas/microbiologia , Ascomicetos/efeitos dos fármacos , Ascomicetos/metabolismo , Ascomicetos/patogenicidade , Fungicidas Industriais/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Triticum/microbiologia , Azóis/farmacologia , Ergosterol/biossíntese , Ergosterol/metabolismo , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Autofagia/efeitos dos fármacos , Membrana Celular/metabolismo , Membrana Celular/efeitos dos fármacos , Oryza/microbiologia , Oryza/metabolismo , Triazóis/farmacologia , Produtos Agrícolas/microbiologia
10.
Curr Microbiol ; 81(7): 173, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38750329

RESUMO

The ability of fungi to effectively sense and internalize signals related to extracellular changing environments is essential for survival. This adaptability is particularly important for fungal pathogens of humans and plants that must sense and respond to drastic environmental changes when colonizing their hosts. One of the most important physicochemical factors affecting fungal growth and development is the pH. Ascomycota fungal species possess mechanisms such as the Pal/Rim pathway for external pH sensing and adaptation. However, the conservation of this mechanism in other fungi, such as Ustilaginomycetes is still little studied. To overcome this knowledge gap, we used a comparative genomic approach to explore the conservation of the Pal/Rim pathway in the 13 best sequenced and annotated Ustilaginomycetes. Our findings reveal that the Rim proteins and the Endosomal Sorting Complex Required for Transport (ESCRT) proteins are conserved in Ustilaginomycetes. They conserve the canonical domains present in Pal/Rim and ESCRT proteins of Ascomycota. This study sheds light on the molecular mechanisms used by these fungi for responding to extracellular stresses such as the pH, and open the door to further experimentations for understanding the molecular bases of the signaling in Ustilaginomycetes.


Assuntos
Proteínas Fúngicas , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Concentração de Íons de Hidrogênio , Transdução de Sinais , Ascomicetos/genética , Ascomicetos/metabolismo , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Complexos Endossomais de Distribuição Requeridos para Transporte/genética , Filogenia
11.
Appl Microbiol Biotechnol ; 108(1): 317, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38700737

RESUMO

Perylenequinones (PQs) are natural photosensitizing compounds used as photodynamic therapy, and heat stress (HS) is the main limiting factor of mycelial growth and secondary metabolism of fungi. This study aimed to unravel the impact of HS-induced Ca2+ and the calcium signaling pathway on PQ biosynthesis of Shiraia sp. Slf14(w). Meanwhile, the intricate interplay between HS-induced NO and Ca2+ and the calcium signaling pathway was investigated. The outcomes disclosed that Ca2+ and the calcium signaling pathway activated by HS could effectively enhance the production of PQs in Shiraia sp. Slf14(w). Further investigations elucidated the specific mechanism through which NO signaling molecules induced by HS act upon the Ca2+/CaM (calmodulin) signaling pathway, thus propelling PQ biosynthesis in Shiraia sp. Slf14(w). This was substantiated by decoding the downstream positioning of the CaM/CaN (calcineurin) pathway in relation to NO through comprehensive analyses encompassing transcript levels, enzyme assays, and the introduction of chemical agents. Concurrently, the engagement of Ca2+ and the calcium signaling pathway in heat shock signaling was also evidenced. The implications of our study underscore the pivotal role of HS-induced Ca2+ and the calcium signaling pathway, which not only participate in heat shock signal transduction but also play an instrumental role in promoting PQ biosynthesis. Consequently, our study not only enriches our comprehension of the mechanisms driving HS signaling transduction in fungi but also offers novel insights into the PQ synthesis paradigm within Shiraia sp. Slf14(w). KEY POINTS: • The calcium signaling pathway was proposed to participate in PQ biosynthesis under HS. • HS-induced NO was revealed to act upon the calcium signaling pathway for the first time.


Assuntos
Ascomicetos , Sinalização do Cálcio , Perileno , Perileno/análogos & derivados , Quinonas , Ascomicetos/metabolismo , Ascomicetos/genética , Ascomicetos/crescimento & desenvolvimento , Quinonas/metabolismo , Perileno/metabolismo , Óxido Nítrico/metabolismo , Resposta ao Choque Térmico , Cálcio/metabolismo , Temperatura Alta
12.
Biomolecules ; 14(5)2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38785924

RESUMO

Cytokinins (CKs) and abscisic acid (ABA) play an important role in the life of both plants and pathogenic fungi. However, the role of CKs and ABA in the regulation of fungal growth, development and virulence has not been sufficiently studied. We compared the ability of two virulent isolates (SnB and Sn9MN-3A) and one avirulent isolate (Sn4VD) of the pathogenic fungus Stagonospora nodorum Berk. to synthesize three groups of hormones (CKs, ABA and auxins) and studied the effect of exogenous ABA and zeatin on the growth, sporulation and gene expression of necrotrophic effectors (NEs) and transcription factors (TFs) in them. Various isolates of S. nodorum synthesized different amounts of CKs, ABA and indoleacetic acid. Using exogenous ABA and zeatin, we proved that the effect of these hormones on the growth and sporulation of S. nodorum isolates can be opposite, depends on both the genotype of the isolate and on the concentration of the hormone and is carried out through the regulation of carbohydrate metabolism. ABA and zeatin regulated the expression of fungal TF and NE genes, but correlation analysis of these parameters showed that this effect depended on the genotype of the isolate. This study will contribute to our understanding of the role of the hormones ABA and CKs in the biology of the fungal pathogen S. nodorum.


Assuntos
Ácido Abscísico , Ascomicetos , Citocininas , Ácido Abscísico/metabolismo , Citocininas/metabolismo , Ascomicetos/metabolismo , Ascomicetos/patogenicidade , Ascomicetos/genética , Ascomicetos/efeitos dos fármacos , Virulência , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Doenças das Plantas/microbiologia , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Zeatina/metabolismo , Zeatina/farmacologia , Esporos Fúngicos/crescimento & desenvolvimento , Esporos Fúngicos/metabolismo , Esporos Fúngicos/efeitos dos fármacos , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética
13.
Curr Microbiol ; 81(7): 195, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38809483

RESUMO

The endolichenic fungi are an unexplored group of organisms for the production of bioactive secondary metabolites. The aim of the present study is to determine the antibacterial potential of endolichenic fungi isolated from genus Parmotrema. The study is continuation of our previous work, wherein a total of 73 endolichenic fungi were isolated from the lichenized fungi, which resulted in 47 species under 23 genera. All the isolated endolichenic fungi were screened for preliminary antibacterial activity. Five endolichenic fungi-Daldinia eschscholtzii, Nemania diffusa, Preussia sp., Trichoderma sp. and Xylaria feejeensis, were selected for further antibacterial activity by disc diffusion method. The zone of inhibition ranged from 14.3 ± 0.1 to 23.2 ± 0.1. The chemical composition of the selected endolichenic fungi was analysed through GC-MS, which yielded a total of 108 compounds from all the selected five endolichenic fungi. Diethyl phthalate, 1-hexadecanol, dibutyl phthalate, n-tetracosanol-1, 1-nonadecene, pyrrol[1,2-a] pyrazine-1,4-dione, hexahydro-3-(2-methyl) and tetratetracontane were found to be common compounds among one or the other endolichenic fungi, which possibly were responsible for antibacterial activity. GC-MS data were further analysed through Principal Component Analysis which showed D. eschscholtzii to be with unique pattern of expression of metabolites. Compound confirmation test revealed coumaric acid to be responsible for antibacterial activity in D. eschscholtzii. So, the study proves that endolichenic fungi that inhabit lichenized fungal thalli could be a source of potential antibacterial compounds.


Assuntos
Antibacterianos , Testes de Sensibilidade Microbiana , Metabolismo Secundário , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/metabolismo , Líquens/microbiologia , Líquens/química , Bactérias/efeitos dos fármacos , Bactérias/classificação , Bactérias/metabolismo , Ascomicetos/metabolismo , Ascomicetos/química , Cromatografia Gasosa-Espectrometria de Massas
14.
Microb Cell Fact ; 23(1): 156, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38802818

RESUMO

BACKGROUND: Biosynthesis of metallic nanoparticles using microorganisms are a fabulous and emerging eco-friendly science with well-defined sizes, shapes and controlled monodispersity. Copper nanoparticles, among other metal particles, have sparked increased attention due to their applications in electronics, optics, catalysis, and antimicrobial agents. RESULTS: This investigation explains the biosynthesis and characterization of copper nanoparticles from soil strains, Niallia circulans G9 and Paenibacillus sp. S4c by an eco-friendly method. The maximum reduction of copper ions and maximum synthesis CuNPs was provided by these strains. Biogenic formation of CuNPs have been characterized by UV-visible absorption spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy, X-ray analysis and transmission electron microscopy analysis. Using UV-visible spectrum scanning, the synthesised CuNPs' SPR spectra showed maximum absorption peaks at λ304&308 nm. TEM investigation of the produced CuNPs revealed the development of spherical/hexagonal nanoparticles with a size range of 13-100 nm by the G9 strain and spherical nanoparticles with a size range of 5-40 nm by the S4c strain. Functional groups and chemical composition of CuONPs were also confirmed. The antimicrobial activity of the biosynthesized CuNPs were investigated against some human pathogens. CuNPs produced from the G9 strain had the highest activity against Candida albicans ATCC 10,231 and the lowest against Pseudomonas aeruginosa ATCC 9027. CuNPs from the S4c strain demonstrated the highest activity against Escherichia coli ATCC 10,231 and the lowest activity against Klebsiella pneumonia ATCC 13,883. CONCLUSION: The present work focused on increasing the CuNPs production by two isolates, Niallia circulans G9 and Paenibacillus sp. S4c, which were then characterized alongside. The used analytics and chemical composition techniques validated the existence of CuONPs in the G9 and S4c biosynthesized nano cupper. CuNPs of S4c are smaller and have a more varied shape than those of G9 strain, according to TEM images. In terms of antibacterial activity, the biosynthesized CuNPs from G9 and S4c were found to be more effective against Candida albicans ATCC 10,231 and E. coli ATCC 10,231, respectively.


Assuntos
Cobre , Nanopartículas Metálicas , Paenibacillus , Paenibacillus/metabolismo , Nanopartículas Metálicas/química , Cobre/química , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/metabolismo , Testes de Sensibilidade Microbiana , Antibacterianos/biossíntese , Antibacterianos/farmacologia , Antibacterianos/química , Ascomicetos/efeitos dos fármacos , Ascomicetos/metabolismo
15.
PLoS Pathog ; 20(5): e1012176, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38709846

RESUMO

Magnaporthe AVRs and ToxB-like (MAX) effectors constitute a family of secreted virulence proteins in the fungus Pyricularia oryzae (syn. Magnaporthe oryzae), which causes blast disease on numerous cereals and grasses. In spite of high sequence divergence, MAX effectors share a common fold characterized by a ß-sandwich core stabilized by a conserved disulfide bond. In this study, we investigated the structural landscape and diversity within the MAX effector repertoire of P. oryzae. Combining experimental protein structure determination and in silico structure modeling we validated the presence of the conserved MAX effector core domain in 77 out of 94 groups of orthologs (OG) identified in a previous population genomic study. Four novel MAX effector structures determined by NMR were in remarkably good agreement with AlphaFold2 (AF2) predictions. Based on the comparison of the AF2-generated 3D models we propose a classification of the MAX effectors superfamily in 20 structural groups that vary in the canonical MAX fold, disulfide bond patterns, and additional secondary structures in N- and C-terminal extensions. About one-third of the MAX family members remain singletons, without strong structural relationship to other MAX effectors. Analysis of the surface properties of the AF2 MAX models also highlights the high variability within the MAX family at the structural level, potentially reflecting the wide diversity of their virulence functions and host targets.


Assuntos
Ascomicetos , Proteínas Fúngicas , Doenças das Plantas , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Ascomicetos/genética , Ascomicetos/patogenicidade , Ascomicetos/metabolismo , Doenças das Plantas/microbiologia , Modelos Moleculares , Conformação Proteica , Virulência , Fatores de Virulência/genética , Fatores de Virulência/química , Fatores de Virulência/metabolismo , Sequência de Aminoácidos
16.
Bioorg Chem ; 148: 107438, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38761703

RESUMO

The synergism of host Paris polyphylla medium, the monoculture, and the coculture led to seventeen new metabolites, including eight sesquiterpenes, 1-7 having uncommon structural motifs compared to similar caryophyllene derivatives, 8 with an unprecedented bicyclic framework, and three xyloketals (13-15) with unprecedented frameworks from Nigrospora lacticolonia; one polyketide, 17 with novel bicyclo [2.2.2] undecane skeleton, and five polyketide-terpenoid hybrids, 20 (one novel sulfated), 21-24 from Penicillium rubens. The structures were determined mainly by the NMR, HRESIMS, ECD calculation, and single-crystal X-ray diffraction. Nine cryptic compounds (2-4, 5, 12-15, 17) were produced by the inductions of host medium and the coculture. The compounds 13 from N. lacticolonia, 24-26, 28, 29, and 31 from P. rubens indicated significant antiphytopathogenic activities against N. lacticolonia with MICs at 2-4 µg/mL. Moreover, compounds 22-26, 28, 29, and 31 from P. rubens showed antifungal activities against P. rubens with MICs at 2-4 µg/mL. The synergistic effects of host medium and the coculture can induce the structural diversity of metabolites.


Assuntos
Técnicas de Cocultura , Penicillium , Penicillium/química , Penicillium/metabolismo , Penicillium/efeitos dos fármacos , Estrutura Molecular , Ascomicetos/efeitos dos fármacos , Ascomicetos/química , Ascomicetos/metabolismo , Relação Estrutura-Atividade , Antifúngicos/farmacologia , Antifúngicos/química , Testes de Sensibilidade Microbiana , Relação Dose-Resposta a Droga
17.
Microbiol Res ; 285: 127779, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38810485

RESUMO

Guanine nucleotide-binding proteins of the ADP ribosylation factor (Arf) family and their activating proteins (Arf-GAPs) are essential for diverse biological processes. Here, two homologous Arf-GAPs, Age1 (AoAge1) and Age2 (AoAge2), were identified in the widespread nematode-trapping fungus Arthrobotrys oligospora. Our results demonstrated that AoAge1, especially AoAge2, played crucial roles in mycelial growth, sporulation, trap production, stress response, mitochondrial activity, DNA damage, endocytosis, reactive oxygen species production, and autophagy. Notably, transcriptome data revealed that approximately 62.7% of the genes were directly or indirectly regulated by AoAge2, and dysregulated genes in Aoage2 deletion were enriched in metabolism, ribosome biogenesis, secondary metabolite biosynthesis, and autophagy. Furthermore, Aoage2 inactivation caused a substantial reduction in several compounds compared to the wild-type strain. Based on these results, a regulatory network for AoAge1 and AoAge2 was proposed and verified using a yeast two-hybrid assay. Based on our findings, AoAge1 and AoAge2 are essential for vegetative growth and mycelial development. Specifically, AoAge2 is required for sporulation and trapping morphogenesis. Our results demonstrated the critical functions of AoAge1 and AoAge2 in mycelial growth, diverse cellular processes, and pathogenicity, offering deep insights into the functions and regulatory mechanisms of Arf-GAPs in nematode-trapping fungi.


Assuntos
Ascomicetos , Proteínas Fúngicas , Regulação Fúngica da Expressão Gênica , Metabolismo Secundário , Esporos Fúngicos , Esporos Fúngicos/crescimento & desenvolvimento , Esporos Fúngicos/genética , Esporos Fúngicos/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Ascomicetos/genética , Ascomicetos/metabolismo , Ascomicetos/crescimento & desenvolvimento , Espécies Reativas de Oxigênio/metabolismo , Autofagia , Micélio/crescimento & desenvolvimento , Micélio/metabolismo , Micélio/genética , Fatores de Ribosilação do ADP/metabolismo , Fatores de Ribosilação do ADP/genética , Animais , Transcriptoma , Virulência , Dano ao DNA , Perfilação da Expressão Gênica
18.
Cell ; 187(10): 2557-2573.e18, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38729111

RESUMO

Many of the world's most devastating crop diseases are caused by fungal pathogens that elaborate specialized infection structures to invade plant tissue. Here, we present a quantitative mass-spectrometry-based phosphoproteomic analysis of infection-related development by the rice blast fungus Magnaporthe oryzae, which threatens global food security. We mapped 8,005 phosphosites on 2,062 fungal proteins following germination on a hydrophobic surface, revealing major re-wiring of phosphorylation-based signaling cascades during appressorium development. Comparing phosphosite conservation across 41 fungal species reveals phosphorylation signatures specifically associated with biotrophic and hemibiotrophic fungal infection. We then used parallel reaction monitoring (PRM) to identify phosphoproteins regulated by the fungal Pmk1 MAPK that controls plant infection by M. oryzae. We define 32 substrates of Pmk1 and show that Pmk1-dependent phosphorylation of regulator Vts1 is required for rice blast disease. Defining the phosphorylation landscape of infection therefore identifies potential therapeutic interventions for the control of plant diseases.


Assuntos
Proteínas Fúngicas , Oryza , Doenças das Plantas , Fosforilação , Oryza/microbiologia , Oryza/metabolismo , Doenças das Plantas/microbiologia , Proteínas Fúngicas/metabolismo , Fosfoproteínas/metabolismo , Ascomicetos/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Proteômica , Transdução de Sinais
19.
Int J Food Microbiol ; 419: 110750, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38776709

RESUMO

Brown rot symptoms may be linked to alterations in the gene expression pattern of genes associated with cell wall degradation. In this study, we identify key carbohydrate-active enzymes (CAZymes) involved in cell wall degradation by Monilinia fructicola, including pme2 and pme3 (pectin methylesterases), cut1 (cutinase) and nep2 (necrosis-inducing factor). The expression of these genes is significantly modulated by red and blue light during early nectarine infection. The polygalacturonase gene pg1 and the cellulase gene cel1 also exhibit photoinduction albeit to a lesser extent. Red and blue light cause an acceleration in the initial stages of brown rot development caused by M. fructicola on nectarines. Disease symptoms like tissue maceration were evident after an incubation period of 24 h followed by 14 h of light exposition, in contrast to the usual incubation period of 48 to 72 h. Furthermore, the culture media exerts an impact on gene regulation, suggesting a complex interplay between light and nutrient signalling pathways in M. fructicola. In addition, we observe that red light promotes colony growth on a 12 h photoperiod and consistently reduces conidiation. In contrast, blue light hampers growth rate on both the 12 h and the 8 h photoperiod but only diminishes conidiation on the 12 h photoperiod. These findings enhance our comprehension of genes associated with cell wall degradation and the environmental factors influencing brown rot development.


Assuntos
Ascomicetos , Parede Celular , Parede Celular/metabolismo , Ascomicetos/genética , Ascomicetos/metabolismo , Doenças das Plantas/microbiologia , Luz , Regulação Fúngica da Expressão Gênica , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo
20.
Chem Biodivers ; 21(6): e202400567, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38602253

RESUMO

Five new cytochalasins, diaporchalasins A-E (1-5), together with 14 known congeners (6-19) were isolated from the endophytic fungus Diaporthe sp. BMX12, which was isolated from the branches of Aquilaria sinensis. The structures of the new compounds were elucidated by extensive spectroscopic analyses including high-resolution electron spray ionization mass spectrometry (HR-ESI-MS) and nuclear magnetic resonance (NMR). Their absolute configurations were assigned by theoretical electronic circular dichroism (ECD) calculations. Compounds 11 and 12 featuring a keto carbonyl at C-21 displayed cytotoxicity toward K562, BEL-7402, SGC-7901, A549, and HeLa cell lines with IC50 values ranging from 4.4 to 47.4 µM.


Assuntos
Ascomicetos , Citocalasinas , Ensaios de Seleção de Medicamentos Antitumorais , Thymelaeaceae , Citocalasinas/química , Citocalasinas/farmacologia , Citocalasinas/isolamento & purificação , Humanos , Thymelaeaceae/química , Thymelaeaceae/microbiologia , Ascomicetos/química , Ascomicetos/metabolismo , Linhagem Celular Tumoral , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Estrutura Molecular , Proliferação de Células/efeitos dos fármacos , Relação Estrutura-Atividade , Relação Dose-Resposta a Droga , Conformação Molecular , Sobrevivência Celular/efeitos dos fármacos
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