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1.
Microbiol Res ; 268: 127299, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36599176

RESUMO

The maintenance of cell-wall integrity (CWI) is important for mycelial growth, development, and pathogenicity in fungi. Arthrobotrys oligospora is a typical nematode-trapping (NT) fungus which can capture nematodes by producing adhesive networks. In this study, we characterized an orthologous MADS-box transcription factor RlmA (AoRlmA) downstream of the CWI regulatory pathway in A. oligospora. The deletion of AorlmA caused a reduction in mycelial growth, the number of nuclei, conidiation, and trap formation, as well as increased sensitivity to cell-wall synthesis-disrupting agents, osmotic agents, and oxidants; accordingly, the transcript levels of genes associated with sporulation, cell-wall biosynthesis, and DNA damage response were downregulated in the ΔAorlmA mutant. Furthermore, the absence of AorlmA resulted in a reduction in autophagy and endocytosis. Transcriptome analysis showed that differentially expressed genes in the absence of AorlmA were involved in membrane components, the oxidation-reduction process, transmembrane transport, metabolic processes, cellular components, organelles, cellular response to stress, and DNA damage response. In addition, metabolomic analysis showed that AoRlmA was involved in the regulation of secondary metabolites of A. oligospora. To summarize, our results highlighted the important roles of transcription factor RlmA in mycelial growth, conidiation, CWI, trap formation, stress response, autophagy, endocytosis, and secondary metabolism regulation in A. oligospora, providing a basis for elucidating the regulatory mechanism of the mycelial growth and development, pathogenicity, and stress response of NT fungi.


Assuntos
Ascomicetos , Nematoides , Animais , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Ascomicetos/metabolismo , Micélio/genética
2.
Sci Rep ; 13(1): 108, 2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36596834

RESUMO

Plant pathogens deliver effector proteins to reprogramme a host plants circuitry, supporting their own growth and development, whilst thwarting defence responses. A subset of these effectors are termed avirulence factors (Avr) and can be recognised by corresponding host resistance (R) proteins, creating a strong evolutionary pressure on pathogen Avr effectors that favours their modification/deletion to evade the immune response. Hence, identifying Avr effectors and tracking their allele frequencies in a population is critical for understanding the loss of host recognition. However, the current systems available to confirm Avr effector function, particularly for obligate biotrophic fungi, remain limited and challenging. Here, we explored the utility of the genetically tractable wheat blast pathogen Magnaporthe oryzae pathotype Triticum (MoT) as a suitable heterologous expression system in wheat. Using the recently confirmed wheat stem rust pathogen (Puccina graminis f. sp. tritici) avirulence effector AvrSr50 as a proof-of-concept, we found that delivery of AvrSr50 via MoT could elicit a visible Sr50-dependant cell death phenotype. However, activation of Sr50-mediated cell death correlated with a high transgene copy number and transcript abundance in MoT transformants. This illustrates that MoT can act as an effective heterologous delivery system for fungal effectors from distantly related fungal species, but only when enough transgene copies and/or transcript abundance is achieved.


Assuntos
Ascomicetos , Basidiomycota , Magnaporthe , Triticum/genética , Triticum/metabolismo , Ascomicetos/metabolismo , Basidiomycota/metabolismo , Doenças das Plantas/microbiologia , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo
3.
J Plant Physiol ; 280: 153887, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36543064

RESUMO

Ascorbate oxidase (AO) and skewed5 (SKU5)-similar (SKS) proteins belong to the multicopper oxidase (MCO) family and play important roles in plants in response to environmental stress via modulation of oxidoreduction homeostasis. Currently, reports on the response of Gossypium barbadense MCO to Verticillium wilt (VW) caused by Verticillium dahliae are still limited. Herein, RNA sequencing of two G. barbadense cultivars of VW-resistant XH21 and VW-susceptible XH7 under V. dahliae treatment, combined with physiological and genetic analysis, was performed to analyze the function and mechanism of multicopper oxidases GbAO and GbSKS involved in V. dahliae resistance. The identified differentially expressed genes are mainly involved in the regulation of oxidoreduction reaction, and extracellular components and signaling. Interestingly, ascorbate oxidase family members were discovered as the most significantly upregulated genes after V. dahliae treatment, including GbAO3A/D, GbSKS3A/D, and GbSKS16A/D. H2O2 and Asc contents, especially reductive Asc in both XH21 and XH7, were shown to be increased. Silenced expression of respective GbAO3A/D, GbSKS3A/D, and GbSKS16A/D in virus-induced gene silencing (VIGS) cotton plants significantly decreased the resistance to V. dahliae, coupled with the reduced contents of pectin and lignin. Our results indicate that AO might be involved in cotton VW resistance via the regulation of cell wall components.


Assuntos
Ascomicetos , Gossypium , Gossypium/genética , Gossypium/metabolismo , Oxirredutases/genética , Oxirredutases/metabolismo , Ascorbato Oxidase/metabolismo , Peróxido de Hidrogênio/metabolismo , Ascomicetos/metabolismo , Resistência à Doença/genética , Doenças das Plantas/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/metabolismo
4.
Angew Chem Int Ed Engl ; 62(6): e202214379, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36484777

RESUMO

Orsellinic acid (OA) derivatives are produced by filamentous fungi using nonreducing polyketide synthases (nrPKSs). The chain-releasing thioesterase (TE) domains of such nrPKSs were proposed to also catalyze dimerization to yield didepsides, such as lecanoric acid. Here, we use combinatorial domain exchanges, domain dissections and reconstitutions to reveal that the TE domain of the lecanoric acid synthase Preu6 of Preussia isomera must collaborate with the starter acyl transferase (SAT) domain from the same nrPKS. We show that artificial SAT-TE fusion proteins are highly effective catalysts and reprogram the ketide homologation chassis to form didepsides. We also demonstrate that dissected SAT and TE domains of Preu6 physically interact, and SAT and TE domains of OA-synthesizing nrPKSs may co-evolve. Our work highlights an unexpected domain-domain interaction in nrPKSs that must be considered for the combinatorial biosynthesis of unnatural didepsides, depsidones, and diphenyl ethers.


Assuntos
Ascomicetos , Policetídeo Sintases , Policetídeo Sintases/metabolismo , Aciltransferases , Ascomicetos/metabolismo
5.
Int J Biol Macromol ; 228: 123-137, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36566811

RESUMO

Valsa mali is a destructive phytopathogenic fungus that mainly infects apple and pear trees. Infection with V. mali results in host tissue acidification via the generation of citric acid, which promote invasion. Here, two plasma membrane H+-ATPases, VmPma1 and VmPma2, were identified in V. mali. The VmPma1 deletion mutant (∆VmPma1) displayed higher intracellular acid accumulation and a lower growth rate compared to the wild type. In contrast, the VmPma2 deletion mutant (∆VmPma2) showed no obvious phenotypic differences. Meanwhile, loss of VmPma1, but not VmPma2, in V. mali led to a significant decrease in growth under acidic or alkaline conditions compared with WT. More importantly, ∆VmPma1 showed a greater reduction in ATPase hydrolase activity and acidification of the external environment, more sensitivity to abiotic stress, and weaker pathogenicity than ∆VmPma2. This evidence indicates that VmPma1 is the main gene of the two plasma membrane H+-ATPases. Transcriptomic analysis indicated that many metabolic processes regulated by VmPma1 are strictly pH-regulated. Besides, we identified two genes (named VmAgn1p and Vmap1) that contribute to the pathogenicity of V. mali by differentially regulating external acidification capacity. Overall, our findings show that VmPma1 plays a pivotal role in pathogenicity by affecting the acidification of V. mali.


Assuntos
Ascomicetos , Malus , Virulência/genética , Doenças das Plantas/microbiologia , Ascomicetos/metabolismo , Malus/metabolismo , Concentração de Íons de Hidrogênio
6.
World J Microbiol Biotechnol ; 39(2): 49, 2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36542187

RESUMO

Microbial exopolysaccharides (EPSs) are mostly produced by bacteria and fungi and have potential use in the production of biomedical products such as nutraceuticals and in tissue engineering applications. The present study investigated the in vitro biological activities and in vivo wound healing effects of EPSs produced from a Sclerotium-forming fungus (Sclerotium glucanicum DSM 2159) and a yeast (Rhodosporidium babjevae), denoted as scleroglucan (Scl) and EPS-R, respectively. EPS yields of 0.9 ± 0.07 g/L and 1.11 ± 0.4 g/L were obtained from S. glucanicum and R. babjevae, respectively. The physicochemical properties of the EPSs were characterized using infrared spectroscopy and scanning electron microscopy. Further investigations of the biological properties showed that both EPSs were cytocompatible toward the human fibroblast cell line and demonstrated  hemocompatibility. Favorable wound healing capacities of the EPSs (10 mg/mL) were also established via in vivo tests. The present study therefore showed that the EPSs produced by S. glucanicum and R. babjevae have the potential use as biocompatible components for the promotion of dermal wound healing.


Assuntos
Ascomicetos , Cicatrização , Humanos , Bactérias/metabolismo , Ascomicetos/metabolismo , Suplementos Nutricionais , Linhagem Celular , Polissacarídeos Bacterianos/farmacologia , Polissacarídeos Bacterianos/metabolismo
7.
Fungal Biol ; 126(11-12): 697-706, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36517138

RESUMO

Lichenized fungi are known for their production of a diversity of secondary metabolites, many of which have broad biological and pharmacological applications. By far the most well-studied of these metabolites is usnic acid. While this metabolite has been well-known and researched for decades, the gene cluster responsible for its production was only recently identified from the species Cladonia uncialis. Usnic acid production varies considerably in the genus Cladonia, even among closely related taxa, and many species, such as C. rangiferina, have been inferred to be incapable of producing the metabolite based on analysis by thin-layer chromatography (TLC). We sequenced and examined the usnic acid biosynthetic gene clusters, or lack thereof, from four closely related Cladonia species (C. oricola, C. rangiferina, C. stygia, and C. subtenuis), and compare them against those of C. uncialis. We complement this comparison with tiered chemical profile analyses to confirm the presence or absence of usnic acid in select samples, using both HPLC and LC-MS. Despite long-standing reporting that C. rangiferina lacks the ability to produce usnic acid, we observed functional gene clusters from the species and detected usnic acid when extracts were examined by LC-MS. By contrast, C. stygia and C. oricola, have been previously described as lacking the ability to produce usnic acid, lacked the gene cluster entirely, and no usnic acid could be detected in C. oricola extracts via HPLC or LC-MS. This work suggests that chemical profiles attained through inexpensive and low-sensitivity methods like TLC may fail to detect low abundance metabolites that can be taxonomically informative. This study also bolsters understanding of the usnic acid gene cluster in lichens, revealing differences among domains of the polyketide synthase which may explain observed differences in expression. These results reinforce the need for comprehensive characterization of lichen secondary metabolite profiles with sensitive LC-MS methods.


Assuntos
Ascomicetos , Benzofuranos , Líquens , Cromatografia Líquida , Líquens/microbiologia , Família Multigênica , Policetídeo Sintases/genética , Policetídeo Sintases/metabolismo , Ascomicetos/genética , Ascomicetos/metabolismo , Benzofuranos/metabolismo
8.
Front Cell Infect Microbiol ; 12: 1045615, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36439212

RESUMO

Proteins containing Common in Fungal Extracellular Membrane (CFEM) domains uniquely exist in fungi and play significant roles in their whole life history. In this study, a total of 11 MbCFEM proteins were identified from Marssonina brunnea f. sp. multigermtubi (MULT), a hemibiotrophic pathogenic fungus on poplars that causes severe leaf diseases. Phylogenic analysis showed that the 11 proteins (MbCFEM1-11) were divided into three clades based on the trans-membrane domain and the CFEM domain. Sequence alignment and WebLogo analysis of CFEM domains verified the amino acids conservatism therein. All of them possess eight cysteines except MbCFEM4 and MbCFEM11, which lack two cysteines each. Six MbCFEM proteins with a signal peptide and without trans-membrane domain were considered as candidate effectors for further functional analysis. Three-dimensional (3D) models of their CFEM domains presented a helical-basket structure homologous to the crucial virulence factor Csa2 of Candida albicans. Afterward, four (MbCFEM1, 6, 8, and 9) out of six candidate effectors were successfully cloned and a yeast signal sequence trap (YSST) assay confirmed their secretion activity. Pathogen challenge assays demonstrated that the transient expression of four candidate MbCFEM effectors in Nicotiana benthamiana promoted Fusarium proliferatum infection, respectively. In an N. benthamiana heterogeneous expression system, MbCFEM1, MbCFEM6, and MbCFEM9 appeared to suppress both BAX/INF1-triggered PCD, whereas MbCFEM8 could only defeat BAX-triggered PCD. Additionally, subcellular localization analysis indicated that the four candidate MbCFEM effectors accumulate in the cell membrane, nucleus, chloroplast, and cytosolic bodies. These results demonstrate that MbCFEM1, MbCFEM6, MbCFEM8, and MbCFEM9 are effectors of M. brunnea and provide valuable targets for further dissection of the molecular mechanisms underlying the poplar-M. brunnea interaction.


Assuntos
Ascomicetos , Populus , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Proteínas de Membrana/metabolismo , Proteína X Associada a bcl-2/metabolismo , Ascomicetos/metabolismo , Populus/metabolismo , Populus/microbiologia
9.
Korean J Parasitol ; 60(5): 345-352, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36320111

RESUMO

Chitinase AO-801 is a hydrolase secreted by Arthrobotrys oligospora during nematode feeding, while its role remained elusive. This study analyzed the molecular characteristics of recombinant chitinase of Arthrobotrys oligospora (reAO-801). AO-801 belongs to the typical glycoside hydrolase 18 family with conserved chitinase sequence and tertiary structure of (α/ß)8 triose-phosphate isomerase (TIM) barrel. The molecular weight of reAO-801 was 42 kDa. reAO-801 effectively degraded colloidal and powdered chitin, egg lysate, and stage I larval lysate of Caenorhabditis elegans. The activity of reAO-801 reached its peak at 40˚C and pH values between 4-7. Enzyme activity was inhibited by Zn2+, Ca2+, and Fe3+, whereas Mg2+ and K+ potentiated its activity. In addition, urea, sodium dodecyl sulfate, and 2-mercaptoethanol significantly inhibited enzyme activity. reAO-801 showed complete nematicidal activity against C. elegans stage I larvae. reAO-801 broke down the C. elegans egg shells, causing them to die or die prematurely by hatching the eggs. It also invoked degradation of Haemonchus contortus eggs, resulting in apparent changes in the morphological structure. This study demonstrated the cytotoxic effect of reAO-801, which laid the foundation for further dissecting the mechanism of nematode infestation by A. oligospora.


Assuntos
Ascomicetos , Quitinases , Nematoides , Animais , Quitinases/metabolismo , Quitinases/farmacologia , Caenorhabditis elegans , Ascomicetos/metabolismo , Larva
10.
Pest Manag Sci ; 78(11): 4850-4858, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36181417

RESUMO

BACKGROUND: Rice blast, caused by Magnaporthe oryzae, is a destructive disease threatening the production of staple foods worldwide. Quinone outside inhibitors (QoIs) are a group of chemicals exhibiting excellent activity against a majority of plant pathogens, with the disadvantage that pathogens can easily develop resistance to QoIs. RESULTS: Here, we investigated the activity of picoxystrobin against M. oryzae, which showed a great inhibitory effect on 100 strains of M. oryzae with half-maximal effective concentrations (EC50 ) ranging from 0.0251 to 0.1337 µg ml-1 . The EC50 values showed a continuous unimodal distribution that was identical to the normal distribution, suggesting the potency of our study to represent baseline sensitivity. In addition, nine resistant mutants were obtained by exposing M. oryzae to a high dosage of picoxystrobin in the laboratory; all of them showed cross-resistance to the other five QoI fungicides. Although some mutants showed a decreased resistance factor after ten successive cultures on fungicide-free medium, the resistance to picoxystrobin was still inheritable. Amino acid substitution of G143S was detected in eight of nine picoxystrobin-resistant mutants, and G143A was detected in only one of nine mutants. A fitness penalty was found in the mutants carrying G143S rather than G143A. CONCLUSION: Our findings suggested that M. oryzae had a mid to high risk of resistance to picoxystrobin. Considering this, we should be vigilant to the resistance risk and apply picoxystrobin sensibly in the field. © 2022 Society of Chemical Industry.


Assuntos
Ascomicetos , Fungicidas Industriais , Magnaporthe , Ascomicetos/metabolismo , Citocromos b/genética , Citocromos b/metabolismo , Fungicidas Industriais/metabolismo , Fungicidas Industriais/farmacologia , Magnaporthe/genética , Doenças das Plantas , Estrobilurinas/farmacologia
11.
Genes (Basel) ; 13(9)2022 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-36140797

RESUMO

Gomphus purpuraceus (Iwade) Yokoyama is a species of wild fungi that grows in southwest China, considered an edible and medicinal fungus with potential commercial prospects. However, the detailed mechanisms related to the development of mycelium and the formation of the fruiting body are unclear. To obtain a comprehensive overview of genetic features, whole-genome and comparative genomics analyses of G. purpuraceus were performed. High-quality DNA was extracted from the mycelium, which was isolated from a fresh fruiting body of G. purpuraceus. The DNA sample was subjected to sequencing using Illumina and Oxford Nanopore sequencing platforms. A genome assembly totaling 40.15 Mb in 50 contigs with an N50 length of 2.06 Mb was generated, and 8705 putative predicted genes were found. Subsequently, phylogenetic analysis revealed a close evolutionary relationship between G. purpuraceus and Gomphus bonarii. Moreover, a total of 403 carbohydrate-active enzymes (CAZymes) were identified in G. purpuraceus, which included 147 glycoside hydrolases (GHs), 85 glycosyl transferases (GTs), 8 polysaccharide lyases (PLs), 76 carbohydrate esterases (CEs), 57 auxiliary activities (AAs) and 30 carbohydrate-binding modules (CBMs). Compared with the other 13 fungi (Laccaria bicolor, Russula virescens, Boletus edulis, etc.), the number and distribution of CAZymes in G. purpuraceus were similar to other mycorrhizal fungi. Furthermore, the optimization of culture medium for G. purpuraceus showed the efficient utilization of disaccharides such as sucrose and maltose. The genome of G. purpuraceus provides new insights into its niche, food applications and potential artificial domestication.


Assuntos
Agaricales , Ascomicetos , Agaricales/genética , Ascomicetos/metabolismo , Metabolismo dos Carboidratos/genética , Domesticação , Esterases/genética , Genômica , Glicosídeo Hidrolases/genética , Maltose , Filogenia , Polissacarídeo-Liases/genética , Sacarose , Transferases/genética
12.
World J Microbiol Biotechnol ; 38(12): 229, 2022 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-36149541

RESUMO

This research investigated the characteristics of Zalaria obscura LS31012019 in terms of growth ability in different media (SDB, YPD and TSB) and temperatures (22, 25 and 37 °C), utilization of several carbon sources (Glucose, Fructose, Lactose, Sucrose, Xylose, Glycerol and Mannitol at 5, 2 and 1%) and several biochemical features (total protein content, Glutathione, pigments), in comparison with those of the phylogenetically related Aureobasidium pullulans ATCC 15233. The best growth of Z. obscura LS31012019 was obtained in YPD at 25 °C with the highest OD value (0.45) after 144 h of incubation, similar to that of A. pullulans ATCC 15233 (0.48). Glucose resulted the preferred carbon source for both the considered yeasts but also sucrose resulted in efficacy supporting the growth of Z. obscura LS31012019 and A. pullulans ATCC 15233, for their ability in converting sucrose to glucose and fructose and the latter into glucose. Interestingly, Z. obscura LS31012019 utilized also glycerol and mannitol. The biochemical analysis showed the similarity of protein profile in Z. obscura LS31012019 and A. pullulans ATCC 15233 (from 90 to 20 kDa) and a reduced GSH content (0.321 and 0.233 µmol/mg). The pigments extraction with hexane generated a yellow oleaginous pellet in both the strains, while a yellow solid matrix more intensely coloured in A. pullulans ATTC 15233 was visible with the following solvent extractions. Overall, our data showed that Z. obscura LS31012019 can grow in different media and temperatures and utilize carbon sources apart from glucose and sucrose, shifting to a non-fermentative metabolism. These results improve the information regarding the characteristics of Z. obscura, opening a new field of investigation for the possible application of new species of black yeasts in human application.


Assuntos
Ascomicetos , Ascomicetos/classificação , Ascomicetos/metabolismo , Carbono/metabolismo
13.
J Agric Food Chem ; 70(37): 11769-11781, 2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36084284

RESUMO

Filamentous fungi produce a great variety of bioactive secondary metabolites essential for their biotic interactions. Here, we characterized an exceptional Trichoderma mutant overproducing harzianic acids (HAs) with exclusively highly antifungal activity against numerous fungi from different ecological groups. Interestingly, two transcription factors (TFs) were identified in this HA biosynthetic gene cluster (hac BGC), with HacI regulating the biosynthetic genes and HacF being likely responsible for the product transportation essential for the self-detoxification of the fungus from the produced HAs. Evolutionary analysis suggested that the sparse distribution of hac BGC in many environmental opportunistic fungi including several species from Trichoderma, Penicillium, and Aspergillus could result from lateral gene transfers and pervasive gene losses in different lineages of Pezizomycotina. Taken together, we propose that the production of HAs by fungi is to inhibit the growth of the surrounding partners to secure an exclusive position in a competitive community.


Assuntos
Ascomicetos , Vias Biossintéticas , Antifúngicos/metabolismo , Ascomicetos/metabolismo , Vias Biossintéticas/genética , Família Multigênica , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
15.
J Agric Food Chem ; 70(34): 10563-10570, 2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-35993186

RESUMO

Sclareol glycol is a key starting material with significant market interest for synthesizing high-value ambroxide, a sustainable substitute for ambergris in high-end fragrances. Sclareol glycol can be obtained by biotransformation of sclareol, a labdane-type diterpene, using Hyphozyma roseonigra. However, the pathway and mechanism of sclareol glycol biosynthesis remain unclear. In this study, the dynamic time course of sclareol biotransformation was explored by resting cell assays and several intermediates produced during biotransformation were detected. The results show that (1) sclareol glycol and sclareolide are not interconverted and are potentially synthesized via different metabolic pathways and (2) several putative intermediates resulting from biotransformation are featured with a labdane carbon backbone, including isomerized and oxidized analogues. A plausible transformation pathway of sclareol in H. roseonigra was proposed based on detected metabolites. This study sheds light on the biosynthetic mechanism of sclareol glycol and paves a way for the future biotechnological production of this promising compound.


Assuntos
Ascomicetos , Diterpenos , Ascomicetos/metabolismo , Biotransformação , Carbono/metabolismo , Diterpenos/metabolismo
16.
Arch Microbiol ; 204(9): 564, 2022 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-35982255

RESUMO

Sanghuangporus sp., a medicinal and edible homologous macrofungus known as 'forest gold', which has good effects on antitumor, hypolipidemia and the treatment of gynecological diseases. However, the natural resources of fruiting body are on the verge of depletion due to its long growth cycle and over exploitation. The growth and metabolism of macrofungi are known to depend on the diverse bacterial community. Here, we characterized the diversity and potential function of bacteria inhabiting in the fruiting body of the most widely applied S. vaninii using a combination method of high-throughput sequencing with pure culturing for the first time, and tested the biological activities of bacterial isolates, of which Illumina NovaSeq provided a more comprehensive results on the bacterial community structure. Total 33 phyla, 82 classes, 195 orders, 355 families, 601 genera and 679 species were identified in the fruiting body, and our results revealed that the community was predominated by the common Proteobacteria, Gammaproteobacteria, Burkholderiales, Methylophilaceae (partly consistent with pure-culturing findings), and was dominated by the genera of distinctive Methylotenera and Methylomonas (yet-uncultured taxa). Simultaneously, the functional analysis showed that companion bacteria were involved in the pathways of carbohydrate transport and metabolism, metabolism of terpenoids and polyketides, cell wall/membrane/envelope biogenesis, etc. Hence, it was inferred that bacteria associated with fruiting body may have the potential to adjust the growth, development and active metabolite production of host S. vaninii combined with the tested results of indole-3-acetic acid and total antioxidant capacity. Altogether, this report first provided new findings which can be inspiring for further in-depth studies to exploit bioactive microbial resources for increased production of Sanghuangporus, as well as to explore the relationship between medicinal macrofungi and their associated endophytes.


Assuntos
Ascomicetos , Basidiomycota , Ascomicetos/metabolismo , Bactérias , Carpóforos/metabolismo , Humanos
17.
Microb Cell Fact ; 21(1): 172, 2022 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-35999640

RESUMO

BACKGROUND: Fungal perylenequinones (PQs) are a class of photoactivated polyketide mycotoxins produced by plant-associated fungi. Hypocrellins, the effective anticancer photodynamic therapy (PDT) agents are main bioactive PQs isolated from a bambusicolous Shiraia fruiting bodies. We found previously that bacterial communities inhabiting fungal fruiting bodies are diverse, but with unknown functions. Bacillus is the most dominant genus inside Shiraia fruiting body. To understand the regulation role of the dominant Bacillus isolates on host fungus, we continued our work on co-culture of the dominant bacterium B. cereus No.1 with host fungus Shiraia sp. S9 to elucidate bacterial regulation on fungal hypocrellin production. RESULTS: Results from "donut" plate tests indicated that the bacterial culture could promote significantly fungal PQ production including hypocrellin A (HA), HC and elsinochrome A-C through bacterial volatiles. After analysis by gas chromatograph/mass spectrometer and confirmation with commercial pure compounds, the volatiles produced by the bacterium were characterized. The eliciting roles of bacterial volatile organic compounds (VOCs) on HA production via transcriptional regulation of host Shiraia fungus were confirmed. In the established submerged bacterial volatile co-culture, bacterial volatiles could not only promote HA production in the mycelium culture, but also facilitate the release of HA into the medium. The total production of HA was reached to 225.9 mg/L, about 1.87 times that of the fungal mono-culture. In contrast, the live bacterium suppressed markedly fungal PQ production in both confrontation plates and mycelium cultures by direct contact. The live bacterium not only down-regulated the transcript levels of HA biosynthetic genes, but also degraded extracellular HA quickly to its reductive product. CONCLUSION: Our results indicated that bacterial volatile release could be a long-distance signal to elicit fungal PQ production. Biodegradation and inhibition by direct contact on fungal PQs were induced by the dominate Bacillus to protect themselves in the fruiting bodies. This is the first report on the regulation of Bacillus volatiles on fungal PQ production. These findings could be helpful for both understanding the intimate fungal-bacterial interactions in a fruiting body and establishing novel cultures for the enhanced production of bioactive PQs.


Assuntos
Ascomicetos , Bacillus cereus , Ascomicetos/metabolismo , Carpóforos , Micélio/metabolismo , Perileno/análogos & derivados , Quinonas
18.
Int J Med Mushrooms ; 24(8): 31-44, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35997093

RESUMO

Doxorubicin (DOX) is an extensively used anticancer drug for chemotherapy. Cardiotoxicity induced by DOX is an impediment in its clinical use. The aim of the current study is to evaluate the effect of a bioactive extract of an excellently edible morel mushroom, Morchella esculenta (ME) to attenuate DOX - induced cardiotoxicity. Protective effect of ME against DOX-induced cytotoxicity was evaluated in vitro by MTT assay using H9C2 cardiomyoblast cells. Intracellular free radical generation and mitochondrial membrane damage caused by DOX were detected by DCF-DA and rhodamine-123 dyes. Elevation of activities of creatine kinase-MB, lactate dehydrogenase and troponin I level consequent to the administration of DOX were determined using diagnostic kits. Depletion of endogenous antioxidant levels in myocardium was determined by spectrophotometric assays. Cardiac tissue damage caused by DOX was assessed by histopathological examination. ME reduced cytotoxicity caused by DOX at concentrations of 150 and 200 µg (p < 0.05 and p < 0.01, respectively). Cardiac injury marker levels elevated by DOX were significantly down regulated by ME (p < 0.01). Endogenous antioxidants such as SOD, GPx, and GSH depleted by DOX administration were restored to almost normal level by ME. This indicated the effect of ME to ameliorate oxidative stress caused by DOX administration leading to myocardial injury. Histopathological observation supported the finding. Being an excellently edible mushroom, current study indicates the potential therapeutic use of M. esculenta to prevent DOX-induced cardiotoxicity. The findings also suggest the clinical use of this medicinal mushroom to prevent chemo drug-induced cardiotoxicity.


Assuntos
Agaricales , Ascomicetos , Agaricales/metabolismo , Antioxidantes/metabolismo , Apoptose , Ascomicetos/metabolismo , Cardiotoxicidade/prevenção & controle , Doxorrubicina/toxicidade , Humanos , Estresse Oxidativo
19.
J Antibiot (Tokyo) ; 75(10): 589-592, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35986093

RESUMO

Biosurfactants have been widely used in various industrial fields including medicine, food, cosmetics, detergent, pulp and paper, and oil and fat degradation. The culture broth of Aureobasidium pullulans A11211-4-57 using glucose as carbon source exhibited potent surfactant activity. The culture broth was separated by column chromatographies using ODS, silica gel, and Sephadex LH-20 resins, consecutively, to provide two biosurfactants. Based on mass and NMR measurements, their structures were determined as myo-inositol lipids and named pullusurfactans F and G. These compounds showed a high degree of activity, with 27.25 mN/m and 24.07 mN/m, respectively, at 1.0 mg l-1, which is useful for washing and cleaning agents.


Assuntos
Ascomicetos , Erigeron , Ascomicetos/metabolismo , Aureobasidium , Tensoativos/química
20.
Int J Mol Sci ; 23(15)2022 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-35955497

RESUMO

Plant diseases cause substantial loss to crops all over the world, reducing the quality and quantity of agricultural goods significantly. One of the world's most damaging plant diseases, rice blast poses a substantial threat to global food security. Magnaporthe oryzae causes rice blast disease, which challenges world food security by causing substantial damage in rice production annually. Autophagy is an evolutionarily conserved breakdown and recycling system in eukaryotes that regulate homeostasis, stress adaption, and programmed cell death. Recently, new studies found that the autophagy process plays a vital role in the pathogenicity of M. oryzae and the regulation mechanisms are gradually clarified. Here we present a brief summary of the recent advances, concentrating on the new findings of autophagy regulation mechanisms and summarize some autophagy-related techniques in rice blast fungus. This review will help readers to better understand the relationship between autophagy and the virulence of plant pathogenic fungi.


Assuntos
Ascomicetos , Magnaporthe , Oryza , Ascomicetos/metabolismo , Autofagia/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Magnaporthe/fisiologia , Oryza/metabolismo , Doenças das Plantas/microbiologia
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