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1.
MycoKeys ; 106: 251-264, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38974462

RESUMO

Two novel species within the family Dictyosporiaceae are described and illustrated from terrestrial habitats on dead culms of bamboo and an unidentified plant, respectively. Through morphological comparisons and the multi-locus phylogenetic analyses of combined LSU, ITS, SSU, and tef1-α sequence dataset, two species, Gregaritheciumbambusicola, Pseudocoleophomaparaphysoidea are identified. Phylogenetically, both species clustered into a monophyletic clade with strong bootstrap support. Gregaritheciumbambusicola sp. nov. can be distinguished from other species within the genus based on its almost straight ascospores. Pseudocoleophomaparaphysoidea sp. nov. differs from other species in its conidiogenous cells intermixed with paraphyses, longer conidiogenous cells and larger conidia. The identification of this lineage contributes to our understanding of the classification of Dictyosporiaceae.

2.
J Fungi (Basel) ; 9(2)2023 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-36836293

RESUMO

Microthyriaceae is typified by the sexual genus Microthyrium, with eight asexual genera. Three interesting isolates were collected during our investigation of freshwater fungi from the wetlands in Guizhou Province, southwest China. Three new asexual morphs are identified. Phylogenetic analyses using ITS and LSU gene regions revealed the placement of these isolates in Microthyriaceae (Microthyriales, Dothideomycetes). Based on the morphology and phylogenetic evidence, two new asexual genera, Paramirandina and Pseudocorniculariella, and three new species, Pa. aquatica, Pa. cymbiformis, and Ps. guizhouensis, are introduced. Descriptions and illustrations of the new taxa are provided, with a phylogenetic tree of Microthyriales and related taxa.

3.
Front Microbiol ; 13: 1003244, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36504805

RESUMO

Aspergillus cristatus is the dominant fungus during the fermentation of Fuzhuan brick tea; hypotonic conditions only induce its sexual development to produce ascospores, while hypertonic conditions only induce its asexual development to produce conidia, indicating that osmotic stress can regulate spore production in A. cristatus. However, the underlying regulatory mechanism is unclear. In this study, the role of Achog1, which is homologous to hog1 from Saccharomyces cerevisiae, in sporulation, different kinds of stress responses and pigment production was investigated. Deletion mutants of Achog1 were obtained by homologous recombination. Phenotypic observations showed that the time required to produce conidia was delayed, and the number of conidia produced was significantly reduced in the deletion mutants of Achog1 in hypertonic media, indicating that Achog1 plays a positive role in asexual development. Stress sensitivity tests showed that ΔAchog1 strains were sensitive to hyperosmolarity, and the order of the sensitivity of ΔAchog1 to different osmotic regulators was 3 M sucrose >3 M NaCl >3 M sorbitol. Moreover, the deletion mutants were sensitive to high oxidative stress. pH sensitivity tests indicated that Achog1 inhibited the growth of A. cristatus under alkaline stress. Additionally, pigmentation was decreased in the Achog1 deletion mutants compared with the WT. All the above developmental defects were reversed by the reintroduction of the Achog1 gene in ΔAchog1. Pull-down and LC-MS/MS analysis showed that the expression levels of proteins interacting with Achog1 were significantly different under low and high osmotic stress, and proteins related to conidial development were present only in the cultures treated with hyperosmotic stress. Transcription profiling data showed that Achog1 suppressed the expression of several genes related to asexual development, osmotic and oxidative stress resistance. On the basis of gene knockout, pull-down mass spectrometry and RNA-seq analyses, a regulatory pathway for Achog1 was roughly identified in A. cristatus.

4.
J Basic Microbiol ; 62(12): 1487-1503, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36192145

RESUMO

Aspergillus cristatus is the dominant fungus during the fermentation of Fuzhuan brick tea, hypotonic conditions only induced its sexual development to produce ascospores, while hypertonic conditions only induced its asexual development to produce conidia, indicating that osmotic stress can regulate spore production in A. cristatus. However, the underlying regulatory mechanism is unclear. In this study, the roles of Acpbs2, which is homologous to pbs2 from Saccharomyces cerevisiae, in sporulation, stress responses, the color of colonies, and carbon metabolism were explored in A. cristatus. Deletion mutants of Acpbs2 were obtained by homologous recombination. The time required to produce conidia was delayed, and the number of conidia produced was significantly reduced in hypertonic media in ΔAcpbs2 by phenotypic observations, indicating that Acpbs2 plays a positive role in asexual development. Stress sensitivity tests showed that the order of the sensitivity of ΔAcpbs2 to different osmotic regulators was 3 M NaCl > 3 M sucrose > 3 M sorbitol. Moreover, the deletion mutants were sensitive to high oxidative stress. The growth of the Acpbs2 deletion mutant was inhibited under alkaline-pH stress, indicating that Acpbs2 is involved in high pH stress tolerance. Additionally, compared with the wild type, the colony color of the Acpbs2 deletion mutant became lighter. All the above developmental defects were reversed by the reintroduction of the Acpbs2 gene in ΔAcpbs2. Transcriptome data showed that Acpbs2 regulated the expression of several genes related to conidial development, osmotic stress, oxidative stress, and carbon metabolism. More importantly, the interaction between Acpbs2 and its downstream gene Achog1 was verified by yeast two-hybrid assays. We speculated that this interaction might regulate the osmotic stress response, the oxidative stress response, and asexual sporulation in A. cristatus, which will be one of the focuses of our future research.


Assuntos
Proteínas Fúngicas , Regulação Fúngica da Expressão Gênica , Proteínas Fúngicas/metabolismo , Carbono/metabolismo , Aspergillus/metabolismo , Esporos Fúngicos
6.
Plant Dis ; 2022 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-35581913

RESUMO

Photinia × fraseri is a well-known evergreeen ornamental tree. Owing to its flower-like red leaves and its ability to tolerate stressful environments, P. fraseri is widely cultured as a fast-growing hedge in southern China. From July to September in 2021, a disease with symptoms similar to leaf spot was extensively observed on P. fraseri in Daozhen county (28° 51 'N, 107° 57 'E), Zunyi, Guizhou province, China. About 500 plants were surveyed and the incidence of leaf spot on P. fraseri leaves was 35% to 70%, significantly reducing the ornamental and economic value. The symptomatic leaves displayed irregular, watery dark brown lesions with black conidiomata in gray centers, and 10 symptomatic leaves were collected from 10 trees. After surface sterilization (0.5 min in 75% ethanol and 2 min in 3% NaOCl, washed three times with sterilized distilled water) (Fang 2007), small pieces of symptomatic leaf tissue (0.2 × 0.2 cm) were plated on potato dextrose agar (PDA) and incubated at 25°C for about 7 days. Three single-spore isolates, GZAAS 21-0327, GZAAS 21-0328 and GZAAS 21-0329, were obtained, which were identical in morphology and molecular analysis. Therefore, the representative isolate GZAAS 21-0328 was used for further study. The pathogenicity of GZAAS 21-0328 was tested through a pot assay. Ten healthy plants were scratched with a sterilized needle on the leaves. Plants were inoculated by spraying a spore suspension (106 spores mL-1) of GZAAS 21-0328 onto leaves until runoff, and the control leaves sprayed with sterile water. The plants were maintained at 28°C with high relative humidity (95%) in a growth chamber. The pathogenicity test was carried out three times (Fang 2007). The symptoms developed on all inoculated leaves but not on the control leaves. The lesions were first visible 72 h after inoculation, and typical lesions similar to those observed on field plants appeared after 15 days. The same fungus was reisolated and identified based on the morphological characterization and molecular analyses (ITS, TUB and TEF) from the infected leaves but not from the noninoculated leaves. Results of pathogenicity experiments of isolated fungi fulfilled Koch's postulates. Fungal colonies on PDA were villiform, creamy-white and sparse aerial mycelium on the surface with black, gregarious conidiomata. The conidia were fusoid, ellipsoid, straight to slightly curved, 4-septate, septa darker than the rest of the cell, and 23.0 (21.0 to 27.0) × 6.0 (5.0 to 7.0) µm (n=50). The morphological features were consistent with the descriptions of Neopestalotiopsis asiatica Maharachch. & K.D. Hyde (Maharachchikumbura et al. 2012; Maharachchikumbura et al. 2014; Farr et al. 2022). The pathogen was confirmed to be N. asiatica by amplification and sequencing of the internal transcribed spacer region (ITS), the partial ß-tubulin (TUB) and partial translation elongation factor 1-alpha (TEF) genes using primers ITS4/ITS5, T1/Bt-2b and EF1-728F/EF-2, respectively (Maharachchikumbura et al. 2014). The sequences of PCR products were deposited in GenBank with accession numbers OK563071 (ITS), OK584020 (TUB) and OK663023 (TEF). BLAST searches of the obtained sequences revealed 100% (482/482 nucleotides), 99.05% (419/421 nucleotides), and 99.33% (891/897 nucleotides) homology with those of N. asiatica in GenBank (JX398983, JX399018 and JX399049, respectively). Phylogenetic analysis (MEGA 6.0) using the maximum likelihood method placed the isolate GZAAS 21-0328 in a well-supported cluster with N. asiatica. The pathogen was thus identified as N. asiatica based on the morphological characterization and molecular analyses. To our knowledge, this is the first report of leaf spot on P. fraseri caused by N. asiatica in China. This study provides valuable information for the identification and control of the leaf spot on Photinia × fraseri.

7.
Biodivers Data J ; 10: e80122, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35437398

RESUMO

Background: An asexual fungus, collected from diseased leaves of Paphiopedilum sp. from Guizhou Province, China, and based on the phylogenetic analyses and morphological characters, it was identified as a new species in Curvicladiella. The genus Curvicladiella are recorded for the first time for China. New information: The morphology of Curvicladiellapaphiopedili sp. nov. is characterised by penicillate conidiophores with a stipe, dull, tapering towards the apex, the curved stipe extension and cylindrical conidia. In the phylogenetic analyses of combined cmdA, his3, ITS, LSU, tef1 and tub2 sequence data, this taxon was clustered as sister to Curvicladiellacignea within Nectriaceae.

8.
J Fungi (Basel) ; 7(11)2021 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-34829232

RESUMO

Distoseptispora is one of the sporidesmium-like taxa with great variation in asexual morphology and delineation of species. Phylogenetic analyses of four gene regions LSU, ITS, TEF1α, and RPB2 revealed the placement of several sporidesmium-like species in Distoseptispora (Distoseptisporaceae, Distoseptisporales, Sordariomycetes), collected on submerged decaying twigs from streams in China and Thailand. Based on morphological examination and molecular DNA data, six new species, Distoseptispora amniculi, D. atroviridis, D. effusa, D. fusiformis, D. hyalina, and D. verrucosa, are proposed. Among them, D. hyalina is the first sexual morph confirmed in the genus. A new geographical record is reported for D. lignicola in China. Conidial length proved to be of less taxonomic significance for some Distoseptispora species, whereas the type of conidial septa is informative at species level.

9.
J Basic Microbiol ; 61(11): 1035-1047, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34596896

RESUMO

Filamentous fungi reproduce sexually or asexually, and the developmental processes are strictly regulated by a variety of transcription factors. In this study, we characterized a zinc finger transcription factor, called AcrpnR, in Aspergillus cristatus (GME2916). The ∆AcrpnR strain exhibited decreased asexual reproduction and increased cleistothecium production. The complementation strain showed restoration of these phenotypic differences. Overexpression of AcrpnR resulted in enhanced asexual development and delayed and inhibited sexual reproduction, suggesting that AcrpnR is required for proper asexual and sexual development in A. cristatus. In addition, AcrpnR positively regulated the expression of genes of the central regulatory pathway of conidiation and negatively regulated the expression of sex-related genes. Overall, these results demonstrate that AcrpnR is essential for maintaining a balance between asexual and sexual development.


Assuntos
Aspergillus/crescimento & desenvolvimento , Proteínas Fúngicas/metabolismo , Fatores de Transcrição/metabolismo , Aspergillus/metabolismo , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica , Teste de Complementação Genética , Mutação , Reprodução Assexuada/genética , Esporos Fúngicos/crescimento & desenvolvimento , Esporos Fúngicos/metabolismo , Estresse Fisiológico/genética , Fatores de Transcrição/química , Fatores de Transcrição/genética , Dedos de Zinco
10.
Fungal Biol ; 125(10): 749-763, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34537171

RESUMO

As the dominant fungus during the fermentation of Fuzhuan brick tea, Aspergillus cristatus is easily induced to undergo a sexual cycle under low-salt stress. However, the underlying regulatory mechanism of sexual reproduction is unclear. Here, we report a P53-like transcription factor AcndtA, which encodes an NDT80 DNA binding protein and regulates fungal reproduction, pigmentation and the stress response. Both insertion and deletion mutants of AcndtA exhibited a complete blockade of cleistothecium formation, and overexpressing AcndtA strains (OE: AcndtA) exhibited significantly reduced cleistothecium production, indicating that AcndtA plays a vital role in sexual development. Osmotic stress tests showed that overexpression of AcndtA had a negative impact on growth and conidia production. Additionally, AcndtA insertion, deletion and overexpression mutants exhibited reduced pigment formation. All the above developmental defects were reversed by the re-introduction of the AcndtA gene in ΔAcndtA. Moreover, the growth of AcndtA mutants in carbon-limited medium was better than that of the WT and OE: AcndtA strains, indicating that AcndtA is involved in carbon metabolism. Transcriptional profiling data showed that AcndtA regulated the expression of several genes related to development, osmotic stress and carbon metabolism.


Assuntos
Regulação Fúngica da Expressão Gênica , Osmorregulação , Aspergillus , Carbono , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Pigmentação
11.
Front Microbiol ; 12: 658113, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34295312

RESUMO

Phytophthora nicotianae causes black shank, a serious soil-borne disease, in tobacco. In this study, the Bacillus strain GUMT319 was isolated from the rhizosphere of healthy tobacco plants grown in a field in Guizhou with a high incidence of tobacco black shank. Genome sequencing revealed that GUMT319 contained a single circular chromosome 3,940,023 bp in length, with 4,053 predicted genes and an average GC content of 46.6%. Based on phylogenomic analyses, GUMT319 was designated as Bacillus velezensis. The genome of GUMT319 contained more than 60 genes and 13 gene clusters that have previously been found to be active in antifungal mechanisms, biofilm formation, and chemotaxis motility. Additionally, confocal laser scanning microscopy and scanning electron microscopy showed that GUMT319 formed a spatially organized biofilm in vivo. In addition, lauric acid negatively regulated biofilm formation. This is the first study to report that nicotine in tobacco root exudates was a chemoattractant for biocontrol Bacillus strains. In this study, we identified new interactions between beneficial microorganisms and tobacco roots in the rhizosphere. Moreover, dual culture tests in vitro showed that GUMT319 inhibited the growth of P. nicotianae and also displayed inhibitory effects against eight other plant pathogens, namely, Colletotrichum scovillei, Colletotrichum capsici, Fusarium carminascens, Sclerotinia sclerotiorum, Alternaria alternata, Phomopsis sp., Phyllosticta sorghina, and Exserohilum turcicum. Furthermore, GUMT319 exhibited > 70% control efficiency against tobacco black shank in field experiments conducted in 2018-2020. Thus, GUMT319 was more effective in controlling the incidence of tobacco black shank than other treatments including fungicide application. Overall, these results suggested that GUMT319 (B. velezensis) could be used as a potential biocontrol agent against tobacco black shank.

12.
Front Microbiol ; 12: 661281, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33936017

RESUMO

Arthrinium has a widespread distribution occurring in various substrates (e.g., air, soil debris, plants, lichens, marine algae and even human tissues). It is characterized by the basauxic conidiogenesis in the asexual morph, with apiospores in the sexual morph. In this study, seventeen isolates of Arthrinium were collected in China. Based on their morphology and phylogenetic characterization, four new species (A. biseriale, A. cyclobalanopsidis, A. gelatinosum, and A. septatum) are described and seven known species (A. arundinis, A. garethjonesii, A. guizhouense, A. hydei, A. neosubglobosa, A. phyllostachium and A. psedoparenchymaticum) are identified, of which the sexual morph of three species (A. guizhouense, A. phyllostachium and A. psedoparenchymaticum) and asexual morph of A. garethjonesii are reported for the first time. The detailed descriptions, illustrations and comparisons with related taxa of these new collections are provided. Phylogenetic analyses of combined ITS, LSU, TUB2, and TEF sequence data support their placements in the genus Arthrinium and justify the new species establishments and identifications of known species.

13.
Plant Dis ; 2021 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-33829859

RESUMO

Chinese rose (Rosa chinensis Jacq.) is cultivated for edible flowers in southwestern China (Zhang et al. 2014). In March 2020, a leaf spot disease was observed on about 3-5% leaves of Chinese rose cultivar 'Mohong' in Guizhou Botanical Garden (26°37' 45'' N, 106°43' 10'' E), Guiyang, Guizhou province, China. The symptomatic plants displayed circular, dark brown lesions with black conidiomata in grey centers on leaves, and leaf samples were collected. After surface sterilization (0.5 min in 75% ethanol and 2 min in 3% NaOCl, washed 3 times with sterilized distilled water) (Fang 2007), small pieces of symptomatic leaf tissue (0.3 × 0.3 cm) were plated on potato dextrose agar (PDA) and incubated at 28oC for about 7 days. Two single-spore isolates, GZUMH01 and GZUMH02, were obtained, which were identical in morphology and molecular analysis. Therefore, the representative isolate GZUMH01 was used for further study. The pathogenicity of GZUMH01 was tested through a pot assay. Ten healthy plants were scratched with a sterilized needle on the leaves. Plants were inoculated by spraying a spore suspension (106 spores ml-1) onto leaves until runoff, and the control leaves sprayed with sterile water. The plants were maintained at 25°C with high relative humidity (90 to 95%) in a growth chamber. The pathogenicity test was carried out three times using the method described in Fang (2007). The symptoms developed on all inoculated leaves but not on the control leaves. The lesions were first visible 48 h after inoculation, and typical lesions similar to those observed on field plants after 7 days. The same fungus was re-isolated from the infected leaves but not from the non-inoculated leaves, fulfilling Koch's postulates. Fungal colonies on PDA were villiform and greyish. The conidia were abundant, oval-ellipsoid, aseptate, 15.8 (13.7 to 18.8) × 5.7 (4.3 to 6.8) µm. The fungal colonies, hyphae, and conidia were consistent with the descriptions of Colletotrichum boninense Moriwaki, Toy. Sato & Tsukib. (Damm et al. 2012; Moriwaki et al. 2003). The pathogen was confirmed to be C. boninense by amplification and sequencing of the internal transcribed spacer region (ITS), the glyceraldehyde-3-phosphate dehydrogenase (GADPH), actin (ACT), and chitin synthase 1 (CHS-1) genes using primers ITS1/ITS4, GDF1/GDR1, ACT512F/ACT783R, and CHS-79F/CHS-345R, respectively (Damm et al. 2012; Moriwaki et al. 2003). The sequences of the PCR products were deposited in GenBank with accession numbers MT845879 (ITS), MT861006 (GADPH), MT861007 (ACT), and MT861008 (CHS-1). BLAST searches of the obtained sequences of the ITS, GADPH, ACT, and CHS-1 genes revealed 100% (554/554 nucleotides), 100% (245/245 nucleotides), 97.43% (265/272 nucleotides), and 99.64% (279/280 nucleotides) homology with those of C. boninense in GenBank (JQ005160, JQ005247, JQ005508, and JQ005334, respectively). Phylogenetic analysis (MEGA 6.0) using the maximum likelihood method placed the isolate GZUMH01 in a well-supported cluster with C. boninense. The pathogen was thus identified as C. boninense based on its morphological and molecular characteristics. To our knowledge, this is the first report of the anthracnose disease on R. chinensis caused by C. boninense in the world.

14.
J Colloid Interface Sci ; 579: 12-20, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32570026

RESUMO

Exploring a cheap catalyst with effective activity for oxygen reduction reaction (ORR) to replace precious metal electrocatalysts has gained tremendous attention for several decades. In this study, we designed and synthesized cobalt and nitrogen supported on mesoporous hollow carbon hemisphere (Co/N/HCHs) nanocomposites by a facile and economical approach. Semisphere-shaped mesoporous hollow carbon is self-generated using silica particles as template, followed by a pyrolysis-etching process; and exhibits high electrical conductivity and high specific surface. The unique porous structure of carbon provides significant number of the abundant defective sites and shortens the mass transfer pathway, leading to a greatly enhanced electrocatalytic activity with mainly 4e- reduction. Moreover, the synergistic effects of large electrochemically active areas and good electrical conductivity, resulting from the introduction of Co and N heteroatom, are the main reason for displaying outstanding ORR activity with a high half-wave potential of 0.8 V and the electron transfer numbers of 3.89. Furthermore, an excellent long-term stability (the current density retention of 87.0%) and superb methanol tolerance in alkaline medium are achieved. Undoubtedly, this demonstrates a potential way to strategically design the non-precious metal doped carbon catalysts for wider practical applications.

15.
MycoKeys ; 76: 81-106, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33505198

RESUMO

Karst formations represent a unique eco-environment. Research in the microfungi inhabiting this area is limited. During an ongoing survey of ascomycetous microfungi from karst terrains in Guizhou Province, China, we discovered four new species, which are introduced here as Hypoderma paralinderae, Terriera karsti, T. meitanensis and T. sigmoideospora placed in Rhytismataceae, based on phylogenetic analyses and morphological characters. Molecular analyses, based on concatenated LSU-ITS-mtSSU sequence data, were used to infer phylogenetic affinities. Detail descriptions and comprehensive illustrations of these new taxa are provided and relationships with the allied species are discussed, based on comparative morphology and molecular data.

16.
G3 (Bethesda) ; 10(1): 23-35, 2020 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-31712259

RESUMO

Shiraia bambusicola is a rare medicinal fungus found in China that causes bamboo plants to decay and die with severe infection. Hypocrellin, its main active ingredient, is widely used in several fields, such as medicine, agriculture, and food industry. In this study, to clarify the genomic components, taxonomic status, pathogenic genes, secondary metabolite synthesis pathways, and regulatory mechanisms of S. bambusicola, whole-genome sequencing, assembly, and functional annotation were performed using high-throughput sequencing and bioinformatics approaches. It was observed that S. bambusicola has 33 Mb genome size, 48.89% GC content, 333 scaffolds, 2590 contigs, 10,703 genes, 82 tRNAs, and 21 rRNAs. The total length of the repeat sequence is 2,151,640 bp. The annotation of 5945 proteins was obtained from InterProScan hits based on the Gene Ontology database. Phylogenetic analysis showed that S. bambusicola belongs to Shiraiaceae, a new family of Pleosporales. It was speculated that there are more than two species or genus in Shiraiaceae. According to the annotation, 777 secreted proteins were associated with virulence or detoxification, including 777 predicted by the PHI database, 776 by the CAZY and Fungal CytochromeP450 database, and 441 by the Proteases database. The 252 genes associated with the secondary metabolism of S. bambusicola were screened and enriched into 28 pathways, among which the terpenoids, staurosporine, aflatoxin, and folate synthesis pathways have not been reported in S. bambusicola The T1PKS was the main gene cluster among the 28 secondary metabolite synthesis gene clusters in S. bambusicola The analysis of the T3PKS gene cluster related to the synthesis of hypocrellin showed that there was some similarity between S. bambusicola and 10 other species of fungi; however, the similarity was very low wherein the highest similarity was 17%. The genomic information of S. bambusicola obtained in this study was valuable to understand its genetic function and pathogenicity. The genomic information revealed that several enzyme genes and secreted proteins might be related to their host interactions and pathogenicity. The annotation and analysis of its secondary metabolite synthesis genes and gene clusters will be an important reference for future studies on the biosynthesis and regulation mechanism of the secondary metabolites, contributing to the discovery of new metabolites and accelerating drug development and application.


Assuntos
Ascomicetos/genética , Genoma Fúngico , Anotação de Sequência Molecular , Ascomicetos/classificação , Composição de Bases , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Fases de Leitura Aberta , Filogenia , RNA Ribossômico/genética , RNA de Transferência/genética , Sequenciamento Completo do Genoma
17.
Mycopathologia ; 184(5): 653-660, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31565783

RESUMO

The prevalence of black fungi in the order Chaetothyriales has often been underestimated due to the difficulty of their isolation. In this study, three methods which are often used to isolate black fungi are compared. Enrichment on aromatic hydrocarbon appears effective in inhibiting growth of cosmopolitan microbial species and allows appearance of black fungi. We miniaturized the method for high-throughput purposes. The new procedure saves time, consumes less space and can process multiple samples simultaneously.


Assuntos
Exophiala/isolamento & purificação , Ascomicetos/isolamento & purificação , Exophiala/metabolismo , Fungos , Micotoxinas/biossíntese
18.
Fungal Biol ; 122(10): 952-964, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30227931

RESUMO

veA belongs to the velvet regulatory system that regulates the development and secondary metabolism of many fungi. To identify the function of veA in Aspergillus cristatus, veA deletion mutants were constructed by homologous recombination via Agrobacterium tumefaciens-mediated transformation. Deletion of veA led to increased conidial production and reduced sexual sporulation. The regulatory role of veA in A. cristatus was not light-dependent, and this differed from its role in other Aspergilli. Furthermore, veA deletion mutants were more sensitive to environmental stressors, including salt, osmotic pressure, temperature and pH. In contrast, deletion of veA resulted in increased resistance to oxidative stress. veA also affected aerial vegetative growth. Transcriptomic analysis of the veA-null mutant and wild type indicated that most asexual and sexual development genes were upregulated and downregulated, respectively. These findings confirmed that veA has a positive effect on sexual development but represses conidial formation. Overall, these results suggested that the veA gene plays a critical role in maintaining a developmental balance between asexual and sexual sporulation and is involved in vegetative growth and environmental stress response in A. cristatus.


Assuntos
Aspergillus/crescimento & desenvolvimento , Aspergillus/genética , Proteínas Fúngicas/fisiologia , Estresse Fisiológico/genética , Proteínas Fúngicas/genética , Perfilação da Expressão Gênica , Regulação Fúngica da Expressão Gênica , Resposta ao Choque Térmico/genética , Pressão Osmótica , Estresse Oxidativo/genética , Estresse Salino/genética
19.
MycoKeys ; (36): 83-105, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30057482

RESUMO

A survey of freshwater fungi on submerged wood in China and Thailand resulted in the collection of three species in Dictyocheirospora and four species in Dictyosporium including two new species in the latter genus. Morphological characters and phylogenetic analyses based on ITS, LSU and TEF1α sequence data support their placement in Dictyocheirospora and Dictyosporium (Dictyosporiaceae). An updated backbone tree is provided for the family Dictyosporiaceae. Descriptions and illustrations of the new taxa and re-collections are provided. Four new combinations are proposed for Dictyocheirospora.

20.
J Toxicol ; 2018: 2591924, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29849612

RESUMO

Video tracking based biological early warning system achieved a great progress with advanced computer vision and machine learning methods. Ability of video tracking of multiple biological organisms has been largely improved in recent years. Video based behavioral monitoring has become a common tool for acquiring quantified behavioral data for aquatic risk assessment. Investigation of behavioral responses under chemical and environmental stress has been boosted by rapidly developed machine learning and artificial intelligence. In this paper, we introduce the fundamental of video tracking and present the pioneer works in precise tracking of a group of individuals in 2D and 3D space. Technical and practical issues suffered in video tracking are explained. Subsequently, the toxic analysis based on fish behavioral data is summarized. Frequently used computational methods and machine learning are explained with their applications in aquatic toxicity detection and abnormal pattern analysis. Finally, advantages of recent developed deep learning approach in toxic prediction are presented.

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