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1.
Front Cell Infect Microbiol ; 14: 1367673, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38707512

RESUMEN

Most species of Dothiora are known from the dead parts of various host plants as saprobic fungi in terrestrial habitats occurring in tropical and temperate regions. In the present study, samples of Dothiora were collected from dead twigs and branches of Capparis spinosa, Rhaponticum repens, and an unknown angiosperm plant from the Tashkent and Jizzakh regions of Uzbekistan. Multi-gene phylogenetic analyses based on a combined ITS, LSU, SSU, TEF1, and TUB2 sequence data revealed their taxonomic positions within the Dothideaceae. Three new species of Dothiora, namely, Dothiora capparis, Dothiora rhapontici, and Dothiora uzbekistanica were proposed by molecular and morphological data. Likewise, the phylogenetic relationship and morphology of Dothiora are discussed. In addition, we provide a list of accepted Dothiora species, including host information, distribution, morphology descriptions, and availability of sequence data, to enhance the current knowledge of the diversity within Dothiora.


Asunto(s)
Ascomicetos , ADN de Hongos , Filogenia , Análisis de Secuencia de ADN , ADN de Hongos/genética , Ascomicetos/genética , Ascomicetos/clasificación , Ascomicetos/aislamiento & purificación , Uzbekistán , ADN Ribosómico/genética , Enfermedades de las Plantas/microbiología
2.
Antonie Van Leeuwenhoek ; 117(1): 77, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38717550

RESUMEN

The "Shadegan International Wetland" (SIW) is one of the wetlands internationally recognized in the Ramsar convention. The vegetation of this wetland ecosystem consists of mostly grasses and shrubs that host a large number of fungi including endophytes. In this study, Nigrospora isolates were obtained from healthy plants of this wetland and its surrounding salt marshes and identified based on morphological features and multilocus phylogenetic analyses based on three DNA loci, namely the internal transcribed spacer regions 1 and 2 including the intervening 5.8S nuclear ribosomal DNA (ITS), ß-tubulin (tub2), and elongation factor 1-α (tef1-α). Accordingly, the following Nigrospora species were identified: N. lacticolonia, N. oryzae, N. osmanthi, N. pernambucoensis and a novel taxon N. shadeganensis sp. nov., which is described and illustrated. To the best of our knowledge, 10 new hosts for Nigrospora species are here reported, namely Aeluropus lagopoides, Allenrolfea occidentalis, Anthoxanthum monticola, Arthrocnemum macrostachyum, Cressa cretica, Halocnemum strobilaceum, Seidlitzia rosmarinus, Suaeda vermiculata, Tamarix passerinoides, and Typha latifolia. Moreover, the species N. lacticolonia and N. pernambucoensis are new records for the mycobiota of Iran.


Asunto(s)
Ascomicetos , Endófitos , Filogenia , Poaceae , Humedales , Irán , Endófitos/clasificación , Endófitos/genética , Endófitos/aislamiento & purificación , Poaceae/microbiología , Ascomicetos/genética , Ascomicetos/clasificación , Ascomicetos/aislamiento & purificación , ADN de Hongos/genética , ADN Espaciador Ribosómico/genética , Tubulina (Proteína)/genética
3.
Artículo en Inglés | MEDLINE | ID: mdl-38695275

RESUMEN

We isolated and described a yellow-pigmented strain of bacteria (strain 9143T), originally characterized as an endohyphal inhabitant of an endophytic fungus in the Ascomycota. Although the full-length sequence of its 16S rRNA gene displays 99 % similarity to Luteibacter pinisoli, genomic hybridization demonstrated <30 % genomic similarity between 9143T and its closest named relatives, further supported by average nucleotide identity results. This and related endohyphal strains form a well-supported clade separate from L. pinisoli and other validly named species including the most closely related Luteibacter rhizovicinus. The name Luteibacter mycovicinus sp. nov. is proposed, with type strain 9143T (isolate DBL433), for which a genome has been sequenced and is publicly available from the American Type Culture Collection (ATCC TSD-257T) and from the Leibniz Institute DSMZ (DSM 112764T). The type strain reliably forms yellow colonies across diverse media and growth conditions (lysogeny broth agar, King's Medium B, potato dextrose agar, trypticase soy agar and Reasoner's 2A (R2A) agar). It forms colonies readily at 27 °C on agar with a pH of 6-8, and on salt (NaCl) concentrations up to 2 %. It lacks the ability to utilize sulphate as a sulphur source and thus only forms colonies on minimal media if supplemented with alternative sulphur sources. It is catalase-positive and oxidase-negative. Although it exhibits a single polar flagellum, motility was only clearly visible on R2A agar. Its host range and close relatives, which share the endohyphal lifestyle, are discussed.


Asunto(s)
Ascomicetos , Técnicas de Tipificación Bacteriana , ADN Bacteriano , Endófitos , Filogenia , ARN Ribosómico 16S , Análisis de Secuencia de ADN , Simbiosis , ARN Ribosómico 16S/genética , Ascomicetos/genética , Ascomicetos/clasificación , Ascomicetos/aislamiento & purificación , ADN Bacteriano/genética , Endófitos/genética , Endófitos/clasificación , Endófitos/aislamiento & purificación , Hibridación de Ácido Nucleico , Ácidos Grasos , Composición de Base , Pigmentos Biológicos/metabolismo
4.
J Agric Food Chem ; 72(17): 10023-10030, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38630649

RESUMEN

Some truffles are expensive and, therefore, are prone to food fraud. A particular problem is the differentiation of high-priced Tuber magnatum truffles from cheaper Tuber borchii truffles, both of which are white truffles with similar morphological characteristics. Using an untargeted approach, the volatiles isolated from samples of both species were screened for potential marker compounds by comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry (GC×GC-TOFMS) and statistical analysis of the obtained semiquantitative data. Results suggested bis(methylsulfanyl)methane and furan-2(5H)-one as compounds characterizing T. magnatum and T. borchii, respectively. Exact quantitation of both volatiles by conventional one-dimensional gas chromatography-mass spectrometry in combination with stable isotopologues of the target compounds as internal standards confirmed both as marker compounds. The method is suitable to be used in the routine analysis for the objective species differentiation of T. magnatum and T. borchii.


Asunto(s)
Ascomicetos , Furanos , Cromatografía de Gases y Espectrometría de Masas , Compuestos Orgánicos Volátiles , Compuestos Orgánicos Volátiles/química , Furanos/química , Furanos/análisis , Ascomicetos/química , Ascomicetos/clasificación
5.
Science ; 384(6694): eadj4503, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38662846

RESUMEN

Organisms exhibit extensive variation in ecological niche breadth, from very narrow (specialists) to very broad (generalists). Two general paradigms have been proposed to explain this variation: (i) trade-offs between performance efficiency and breadth and (ii) the joint influence of extrinsic (environmental) and intrinsic (genomic) factors. We assembled genomic, metabolic, and ecological data from nearly all known species of the ancient fungal subphylum Saccharomycotina (1154 yeast strains from 1051 species), grown in 24 different environmental conditions, to examine niche breadth evolution. We found that large differences in the breadth of carbon utilization traits between yeasts stem from intrinsic differences in genes encoding specific metabolic pathways, but we found limited evidence for trade-offs. These comprehensive data argue that intrinsic factors shape niche breadth variation in microbes.


Asunto(s)
Ascomicetos , Carbono , Interacción Gen-Ambiente , Nitrógeno , Ascomicetos/clasificación , Ascomicetos/genética , Ascomicetos/metabolismo , Carbono/metabolismo , Genoma Fúngico , Redes y Vías Metabólicas/genética , Nitrógeno/metabolismo , Filogenia
6.
mBio ; 15(5): e0008624, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38534157

RESUMEN

Dynamic transposition of transposable elements (TEs) in fungal pathogens has significant impact on genome stability, gene expression, and virulence to the host. In Magnaporthe oryzae, genome plasticity resulting from TE insertion is a major driving force leading to the rapid evolution and diversification of this fungus. Despite their importance in M. oryzae population evolution and divergence, our understanding of TEs in this context remains limited. Here, we conducted a genome-wide analysis of TE transposition dynamics in the 11 most abundant TE families in M. oryzae populations. Our results show that these TEs have specifically expanded in recently isolated M. oryzae rice populations, with the presence/absence polymorphism of TE insertions highly concordant with population divergence on Geng/Japonica and Xian/Indica rice cultivars. Notably, the genes targeted by clade-specific TEs showed clade-specific expression patterns and are involved in the pathogenic process, suggesting a transcriptional regulation of TEs on targeted genes. Our study provides a comprehensive analysis of TEs in M. oryzae populations and demonstrates a crucial role of recent TE bursts in adaptive evolution and diversification of the M. oryzae rice-infecting lineage. IMPORTANCE: Magnaporthe oryzae is the causal agent of the destructive blast disease, which caused massive loss of yield annually worldwide. The fungus diverged into distinct clades during adaptation toward the two rice subspecies, Xian/Indica and Geng/Japonica. Although the role of TEs in the adaptive evolution was well established, mechanisms underlying how TEs promote the population divergence of M. oryzae remain largely unknown. In this study, we reported that TEs shape the population divergence of M. oryzae by differentially regulating gene expression between Xian/Indica-infecting and Geng/Japonica-infecting populations. Our results revealed a TE insertion-mediated gene expression adaption that led to the divergence of M. oryzae population infecting different rice subspecies.


Asunto(s)
Elementos Transponibles de ADN , Evolución Molecular , Genoma Fúngico , Oryza , Enfermedades de las Plantas , Elementos Transponibles de ADN/genética , Oryza/microbiología , Enfermedades de las Plantas/microbiología , Virulencia/genética , Variación Genética , Ascomicetos/genética , Ascomicetos/clasificación , Ascomicetos/patogenicidad , Magnaporthe/genética , Magnaporthe/patogenicidad , Magnaporthe/clasificación
7.
Mycologia ; 116(3): 449-463, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38484286

RESUMEN

Proteomics has been used extensively in the field of mycology, mainly in trying to understand the complex network of protein-protein interactions that has been implicated in the molecular functions of fungi. It is also a useful tool to compare metabolic differences within a genus. Species of Pseudogymnoascus, a genus under the phyla Ascomycota, have been shown to play an important role in the soil environment. They have been found in both polar and temperate regions and are a known producer of many extracellular hydrolases that contribute to soil decomposition. Despite the apparent importance of Pseudogymnoascus spp. in the soil ecosystem, investigations into their molecular functions are still very limited. In the present study, proteomic characterization of six Pseudogymnoascus spp. isolated from three biogeographic regions (the Arctic, Antarctic, and temperate regions) was carried out using tandem mass spectrometry. Prior to proteomic analysis, the optimization for protein extraction was carried out. Trichloroacetic acid­acetone­phenol was found to be the best extraction method to be used for proteomic profiling of Pseudogymnoascus spp. The proteomic analysis identified 2003 proteins that were successfully mapped to the UniProtKB database. The identified proteins were clustered according to their biological processes and molecular functions. The shared proteins found in all Pseudogymnoascus spp. (1201 proteins) showed a significantly close relationship in their basic cellular functions, despite differences in morphological structures. Analysis of Pseudogymnoascus spp. proteome also identified proteins that were unique to each region. However, a high number of these proteins belonged to protein families of similar molecular functions, namely, transferases and hydrolases. Our proteomic data can be used as a reference for Pseudogymnoascus spp. across different global regions and a foundation for future soil ecosystem function research.


Asunto(s)
Ascomicetos , Proteínas Fúngicas , Proteómica , Microbiología del Suelo , Ascomicetos/clasificación , Ascomicetos/metabolismo , Ascomicetos/genética , Ascomicetos/química , Ascomicetos/aislamiento & purificación , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Proteoma , Espectrometría de Masas en Tándem , Regiones Árticas
8.
Artículo en Inglés | MEDLINE | ID: mdl-38415711

RESUMEN

A yeast strain (CGMCC 2.6937T) belonging to the ascomycetous yeast genus Saturnispora was recently isolated from soil collected in Xinghuacun, Shanxi Province, PR China. The strain produces one or two ellipsoid or spherical ascospores in asci formed by the conjugation between a cell and its bud. Phylogenetic analyses of the internal transcribed spacer (ITS) region and the D1/D2 domain of the large subunit rRNA gene suggest that this strain is conspecific with strains NYNU 14639 isolated from rotten wood collected in Funiu Mountain, Henan province and ES13S05 from soil collected in Nantou County, Taiwan. The CGMCC 2.6937T group is most closely related to Saturnispora dispora and Saturnispora zaruensis. However, strain CGMCC 2.6937T differs from S. dispora by 17 (3.2 %, 13 substitutions and four gaps) and 77 (18.8 %, 52 substitutions and 25 gaps) mismatches, and from S. zaruensis by 15 (2.9 %, 12 substitutions and three gaps) and 64 (15.6 %, 44 substitutions and 20 gaps) mismatches, in the D1/D2 domain and ITS region, respectively. The results suggest that the CGMCC 2.6937T group represents an undescribed species in the genus Saturnispora, for which the name Saturnispora sinensis sp. nov. is proposed. The holotype strain is CGMCC 2.6937T.


Asunto(s)
Ascomicetos , Filogenia , Microbiología del Suelo , Madera , Ascomicetos/clasificación , Ascomicetos/genética , Composición de Base , Análisis de Secuencia de ADN , Madera/microbiología , Técnicas de Tipificación Micológica
9.
J Agric Food Chem ; 71(46): 18074-18084, 2023 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-37934755

RESUMEN

The price of different truffle types varies according to their culinary value, sometimes by more than a factor of 10. Nonprofessionals can hardly distinguish visually the species within the white or black truffles, making the possibility of food fraud very easy. Therefore, the identification of different truffle species (Tuber spp.) is an analytical task that could be solved in this study. The polar extract from a total of 80 truffle samples was analyzed by 1H NMR spectroscopy in combination with chemometric methods covering five commercially relevant species. All classification models were validated applying a repeated nested cross-validation. In direct comparison, the two very similar looking and closely related black representatives Tuber melanosporum and Tuber indicum could be classified 100% correctly. The most expensive truffle Tuber magnatum could be distinguished 100% from the other relevant white truffle Tuber borchii. In addition, signals for a potential Tuber borchii and a potential Tuber melanosporum marker for targeted approaches could be detected, and the corresponding molecules were identified as betaine and ribonate. A model covering all five truffle species Tuber aestivum, Tuber borchii, Tuber indicum, Tuber magnatum, and Tuber melanosporum was able to correctly discriminate between each of the species.


Asunto(s)
Ascomicetos , Máquina de Vectores de Soporte , Ascomicetos/clasificación
10.
Microbiol Spectr ; 11(3): e0004223, 2023 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-37014218

RESUMEN

Pestalotioid fungi have been frequently studied with respect to their morphology, molecular phylogeny, and pathogenicity. Monochaetia is a pestalotioid genus that is morphologically characterized by 5-celled conidia with single apical and basal appendages. In the present study, fungal isolates were obtained from diseased leaves of Fagaceae hosts in China in 2016 to 2021 and identified based on morphology and phylogenetic analyses of the 5.8S nuclear ribosomal DNA gene with the two flanking internal transcribed spacer (ITS) regions, the nuclear ribosomal large subunit (LSU) region, the translation elongation factor 1-α (tef1) gene, and the ß-tubulin (tub2) gene. As a result, five new species are proposed here, namely, Monochaetia hanzhongensis, Monochaetia lithocarpi, Monochaetia lithocarpicola, Monochaetia quercicola, and Monochaetia shaanxiensis. In addition, pathogenicity tests for these five species and Monochaetia castaneae from Castanea mollissima were conducted with detached leaves of Chinese chestnut. Results demonstrated that only M. castaneae successfully infected the host C. mollissima and caused brown lesions. IMPORTANCE Monochaetia is a pestalotioid genus, with members that are commonly known as leaf pathogens or saprobes; some strains were isolated from air, in which case their natural substrate is so far unknown. Fagaceae represents an ecologically and economically important plant family that is widely distributed in the Northern Hemisphere, including an important tree crop species, Castanea mollissima, which is widely cultivated in China. In the present study, diseased leaves of Fagaceae in China were investigated, and five new Monochaetia species were introduced based on morphology and phylogeny of combined ITS, LSU, tef1, and tub2 loci. Additionally, six species of Monochaetia were inoculated onto healthy leaves of the crop host Castanea mollissima to test their pathogenicity. The present study provides significant data on the species diversity, taxonomy, and host range of Monochaetia and enhances our understanding of leaf diseases of Fagaceae hosts.


Asunto(s)
Ascomicetos , Fagaceae , China , ADN Ribosómico , Filogenia , Virulencia , Ascomicetos/clasificación , Ascomicetos/aislamiento & purificación , Fagaceae/microbiología
11.
World J Microbiol Biotechnol ; 38(12): 229, 2022 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-36149541

RESUMEN

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.


Asunto(s)
Ascomicetos , Ascomicetos/clasificación , Ascomicetos/metabolismo , Carbono/metabolismo
12.
Sci Rep ; 12(1): 11048, 2022 06 30.
Artículo en Inglés | MEDLINE | ID: mdl-35773369

RESUMEN

We show that obligate lignicoles in lichenized Micarea are predominately asexual whereas most facultative lignicoles reproduce sexually. Our phylogenetic analyses (ITS, mtSSU, Mcm7) together with ancestral state reconstruction show that the shift in reproduction mode has evolved independently several times within the group and that facultative and obligate lignicoles are sister species. The analyses support the assumption that the ancestor of these species was a facultative lignicole. We hypothezise that a shift in substrate requirement from bark to wood leads to differentiation in reproduction mode and becomes a driver of speciation. This is the first example of lichenized fungi where reproduction mode is connected to substrate requirement. This is also the first example where such an association is demonstrated to spark lichen speciation. Our main hypothesis is that obligate species on dead wood need to colonize new suitable substrata relatively fast and asexual reproduction is more effective a strategy for successful colonization.


Asunto(s)
Ascomicetos , Líquenes , Filogenia , Ascomicetos/clasificación , Líquenes/clasificación , Reproducción Asexuada
13.
Molecules ; 27(3)2022 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-35163862

RESUMEN

Truffles represent the best known and most expensive edible mushroom. Known as Ascomycetes, they belong to the genus Tuber and live in symbiosis with plant host roots. Due to their extraordinary taste and smell, truffles are sold worldwide for high prices of up to 3000-5000 euros per kilogram (Tuber magnatum PICO). Amongst black truffles, the species Tuber melanosporum VITTAD. is highly regarded for its organoleptic properties. Nonetheless, numerous different sorts of black truffle are offered at lower prices, including Tuber aestivum VITTAD., Tuber indicum and Tuber uncinatum, which represent the most frequently consumed types. Because truffles do not differ visually for inexperienced consumers, food fraud is likely to occur. In particular, for the highly prized Tuber melanosporum, which morphologically forms very similar fruiting bodies to those of Tuber indicum, there is a risk of fraud via imported truffles from Asia. In this study, 126 truffle samples belonging to the four mentioned species were investigated by four different NIR instruments, including three miniaturized devices-the Tellspec Enterprise Sensor, the VIAVI solutions MicroNIR 1700 and the Consumer Physics SCiO-working on different technical principles. Three different types of measurement techniques were applied for all instruments (outer shell, rotational device and fruiting body) in order to identify the best results for classification and quality assurance in a non-destructive manner. Results provided differentiation with an accuracy up to 100% for the expensive Tuber melanosporum from Tuber indicum. Classification between Tuber melanosporum, Tuber indicum, Tuber aestivum and Tuber uncinatum could also be achieved with success of 100%. In addition, quality monitoring including discrimination between fresh and frozen/thawed, and prediction of the approximate date of harvesting, was performed. Furthermore, feasibility studies according to the geographical origin of the truffle were attempted. The presented work compares the performance for prediction and quality monitoring of portable vs. benchtop NIR devices and applied measurement techniques in order to be able to present a suitable, accurate, fast, non-destructive and reliable method for consumers.


Asunto(s)
Ascomicetos/química , Ascomicetos/clasificación , Técnicas Biosensibles/métodos , Contaminación de Alimentos/análisis , Espectroscopía Infrarroja Corta/métodos , Ascomicetos/aislamiento & purificación , Especificidad de la Especie
14.
Genes (Basel) ; 13(1)2022 01 14.
Artículo en Inglés | MEDLINE | ID: mdl-35052485

RESUMEN

True truffle (Tuber spp.) is one group of ascomycetes with great economic importance. During the last 30 years, numerous fine-scale population genetics studies were conducted on different truffle species, aiming to answer several key questions regarding their life cycles; these questions are important for their cultivation. It is now evident that truffles are heterothallic, but with a prevalent haploid lifestyle. Strains forming ectomycorrhizas and germinating ascospores act as maternal and paternal partners respectively. At the same time, a number of large-scale studies were carried out, highlighting the influences of the last glaciation and river isolations on the genetic structure of truffles. A retreat to southern refugia during glaciation, and a northward expansion post glaciation, were revealed in all studied European truffles. The Mediterranean Sea, acting as a barrier, has led to the existence of several refugia in different peninsulas for a single species. Similarly, large rivers in southwestern China act as physical barriers to gene flow for truffles in this region. Further studies can pay special attention to population genetics of species with a wide distribution range, such as T. himalayense, and the correlation between truffle genetic structure and the community composition of truffle-associated bacteria.


Asunto(s)
Ascomicetos/clasificación , Ascomicetos/genética , Genética de Población , Estadios del Ciclo de Vida , Filogeografía , Especificidad de la Especie
15.
Sci China Life Sci ; 65(2): 412-425, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34031812

RESUMEN

Autophagy is an evolutionarily conserved process in eukaryotes, which is regulated by autophagy-related genes (ATGs). Arthrobotrys oligospora is a representative species of nematode-trapping (NT) fungi that can produce special traps for nematode predation. To elucidate the biological roles of autophagy in NT fungi, we characterized an orthologous Atg protein, AoAtg5, in A. oligospora. We found that AoATG5 deletion causes a significant reduction in vegetative growth and conidiation, and that the transcript levels of several sporulation-related genes were significantly downregulated during sporulation stage. In addition, the cell nuclei were significantly reduced in the ΔAoATG5 mutant, and the transcripts of several genes involved in DNA biosynthesis, repair, and ligation were significantly upregulated. In ΔAoATG5 mutants, the autophagic process was significantly impaired, and trap formation and nematocidal activity were significantly decreased. Comparative transcriptome analysis results showed that AoAtg5 is involved in the regulation of multiple cellular processes, such as autophagy, nitrogen metabolism, DNA biosynthesis and repair, and vesicular transport. In summary, our results suggest that AoAtg5 is essential for autophagy and significantly contributes to vegetative growth, cell nucleus development, sporulation, trap formation, and pathogenicity in A. oligospora, thus providing a basis for future studies focusing on related mechanisms of autophagy in NT fungi.


Asunto(s)
Ascomicetos/fisiología , Ascomicetos/patogenicidad , Proteína 5 Relacionada con la Autofagia/metabolismo , Núcleo Celular/metabolismo , Proteínas Fúngicas/metabolismo , Nematodos/microbiología , Animales , Ascomicetos/clasificación , Autofagosomas/metabolismo , Proteína 5 Relacionada con la Autofagia/genética , Núcleo Celular/genética , ADN de Hongos/metabolismo , Proteínas Fúngicas/genética , Perfilación de la Expresión Génica , Hifa/crecimiento & desarrollo , Hifa/metabolismo , Mutación , Nitrógeno/metabolismo , Filogenia , Esporas Fúngicas/fisiología , Transcripción Genética , Virulencia
16.
Microbiol Spectr ; 9(3): e0111821, 2021 12 22.
Artículo en Inglés | MEDLINE | ID: mdl-34937170

RESUMEN

Verticillium dahliae is a widespread soilborne fungus that causes Verticillium wilt on numerous economically important plant species. In tomato, until now, three races have been characterized based on the response of differential cultivars to V. dahliae, but the genetic basis of race divergence in V. dahliae remains undetermined. To investigate the genetic basis of race divergence, we sequenced the genomes of two race 2 strains and four race 3 strains for comparative analyses with two known race 1 genomes. The genetic basis of race divergence was described by the pathogenicity-related genes among the three races, orthologue analyses, and genomic structural variations. Global comparative genomics showed that chromosomal rearrangements are not the only source of race divergence and that race 3 should be split into two genotypes based on orthologue clustering. Lineage-specific regions (LSRs), frequently observed between genomes of the three races, encode several predicted secreted proteins that potentially function as suppressors of immunity triggered by known effectors. These likely contribute to the virulence of the three races. Two genes in particular that can act as markers for race 2 and race 3 (VdR2e and VdR3e, respectively) contribute to virulence on tomato, and the latter acts as an avirulence factor of race 3. We elucidated the genetic basis of race divergence through global comparative genomics and identified secreted proteins in LSRs that could potentially play critical roles in the differential virulence among the races in V. dahliae. IMPORTANCE Deciphering the gene-for-gene relationships during host-pathogen interactions is the basis of modern plant resistance breeding. In the Verticillium dahliae-tomato pathosystem, two races (races 1 and 2) and their corresponding avirulence (Avr) genes have been identified, but strains that lack these two Avr genes exist in nature. In this system, race 3 has been described, but the corresponding Avr gene has not been identified. We de novo-sequenced genomes of six strains and identified secreted proteins within the lineage-specific regions (LSRs) distributed among the genomes of the three races that could potentially function as manipulators of host immunity. One of the LSR genes, VdR3e, was confirmed as the Avr gene for race 3. The results indicate that differences in transcriptional regulation may contribute to race differentiation. This is the first study to describe these differences and elucidate roles of secreted proteins in LSRs that play roles in race differentiation.


Asunto(s)
Ascomicetos/clasificación , Ascomicetos/genética , Genoma Fúngico/genética , Solanum lycopersicum/microbiología , Resistencia a la Enfermedad/genética , Genómica , Genotipo , Interacciones Huésped-Patógeno/genética , Enfermedades de las Plantas/microbiología , Microbiología del Suelo , Transcripción Genética/genética , Virulencia/genética
17.
Int J Syst Evol Microbiol ; 71(11)2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34731078

RESUMEN

A growing interest in fungi that occur within symptom-less plants and lichens (endophytes) has uncovered previously uncharacterized species in diverse biomes worldwide. In many temperate and boreal forests, endophytic Coniochaeta (Sacc.) Cooke (Coniochaetaceae, Coniochaetales, Sordariomycetes, Ascomycota) are commonly isolated on standard media, but rarely are characterized. We examined 26 isolates of Coniochaeta housed at the Gilbertson Mycological Herbarium. The isolates were collected from healthy photosynthetic tissues of conifers, angiosperms, mosses and lichens in Canada, Sweden and the United States. Their barcode sequences (nuclear ribosomal internal transcribed spacer and 5.8S; ITS rDNA) were ≤97% similar to any documented species available through GenBank. Phylogenetic analyses based on two loci (ITS rDNA and translation elongation factor 1-alpha) indicated that two isolates represented Coniochaeta cymbiformispora, broadening the ecological niche and geographic range of a species known previously from burned soil in Japan. The remaining 24 endophytes represented three previously undescribed species that we characterize here: Coniochaeta elegans sp. nov., Coniochaeta montana sp. nov. and Coniochaeta nivea sp. nov. Each has a wide host range, including lichens, bryophytes and vascular plants. C. elegans sp. nov. and C. nivea sp. nov. have wide geographic ranges. C. montana sp. nov. occurs in the Madrean biome of Arizona (USA), where it is sympatric with the other species described here. All three species display protease, chitinase and cellulase activity in vitro. Overall, this study provides insight into the ecological and evolutionary diversity of Coniochaeta and suggests that these strains may be amenable for studies of traits relevant to a horizontally transmitted, symbiotic lifestyle.


Asunto(s)
Ascomicetos , Filogenia , Animales , Ascomicetos/clasificación , Ascomicetos/aislamiento & purificación , Canadá , ADN de Hongos/genética , ADN Espaciador Ribosómico/genética , Endófitos/clasificación , Endófitos/aislamiento & purificación , Técnicas de Tipificación Micológica , Análisis de Secuencia de ADN , Suecia , Estados Unidos
18.
Int J Syst Evol Microbiol ; 71(11)2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34846290

RESUMEN

Exophiala is an important genus, with several species associated with infections in humans and animals. In a survey of soil fungal diversity in Yunnan province, PR China, a novel taxon, Exophiala pseudooligosperma sp. nov., was identified based on combined morphological and molecular phylogenetic features. Morphologically, this species is characterized by having torulose, septate hyphae and swollen, terminal or intercalary conidiogenous cells arising at acute angles from aerial hyphae. Phylogenetic analysis of the combined sequences of the internal transcribed spacer, the small and large nuclear subunit of the rRNA gene and part of the ß-tubulin gene confirmed the phylogenetic position of the new species within the genus Exophiala.


Asunto(s)
Ascomicetos , Exophiala , Filogenia , Microbiología del Suelo , Ascomicetos/clasificación , Ascomicetos/aislamiento & purificación , Composición de Base , China , ADN de Hongos/genética , ADN Espaciador Ribosómico/genética , Exophiala/genética , Técnicas de Tipificación Micológica , Análisis de Secuencia de ADN
19.
Microb Genom ; 7(10)2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34617882

RESUMEN

Pathogens cause significant challenges to global food security. On annual crops, pathogens must re-infect from environmental sources in every growing season. Fungal pathogens have evolved mixed reproductive strategies to cope with the distinct challenges of colonizing growing plants. However, how pathogen diversity evolves during growing seasons remains largely unknown. Here, we performed a deep hierarchical sampling in a single experimental wheat field infected by the major fungal pathogen Zymoseptoria tritici. We analysed whole genome sequences of 177 isolates collected from 12 distinct cultivars replicated in space at three time points of the growing season to maximize capture of genetic diversity. The field population was highly diverse with 37 SNPs per kilobase, a linkage disequilibrium decay within 200-700 bp and a high effective population size. Using experimental infections, we tested a subset of the collected isolates on the dominant cultivar planted in the field. However, we found no significant difference in virulence of isolates collected from the same cultivar compared to isolates collected on other cultivars. About 20 % of the isolate genotypes were grouped into 15 clonal groups. Pairs of clones were disproportionally found at short distances (<5 m), consistent with experimental estimates for per-generation dispersal distances performed in the same field. This confirms predominant leaf-to-leaf transmission during the growing season. Surprisingly, levels of clonality did not increase over time in the field although reproduction is thought to be exclusively asexual during the growing season. Our study shows that the pathogen establishes vast and stable gene pools in single fields. Monitoring short-term evolutionary changes in crop pathogens will inform more durable strategies to contain diseases.


Asunto(s)
Ascomicetos/genética , Hongos/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Enfermedades de las Plantas/microbiología , Ascomicetos/clasificación , Ascomicetos/aislamiento & purificación , Genotipo , Filogenia , Hojas de la Planta/microbiología , Polimorfismo Genético , Polimorfismo de Nucleótido Simple , Reproducción , Virulencia/genética , Secuenciación Completa del Genoma
20.
Microbiol Spectr ; 9(2): e0086721, 2021 10 31.
Artículo en Inglés | MEDLINE | ID: mdl-34612666

RESUMEN

An investigation of members of the soil keratinophilic fungi community in China resulted in the identification of one new monotypic genus, Zongqia, and 10 new species, 2 of which are affiliated with Solomyces, 1 with the new genus Zongqia, 4 with Pseudogymnoascus, and 3 with Scedosporium. These novel taxa form an independent lineage distinct from other species, based on morphological and multilocus phylogenetic analyses. Descriptions, illustrations, and notes are provided for each taxon. These new taxa of the soil keratinophilic fungi add to the increasing number of fungi known from China, and it is now evident that numerous novel taxa are waiting to be described. IMPORTANCE Keratinophilic fungi are a group that can degrade and utilize keratin-rich material. It is also because of this ability that many taxa can cause infections in animals or humans but remain poorly studied. In this study, we reported a novel genus and 10 novel species, 7 novel species belonging to the order Thelebolales and 3 to the genus Scedosporium, based on multilocus phylogenetic analyses combined with morphological characteristics. Our study significantly updates the taxonomy of Thelebolales and Scedosporium and enhances our understanding of this group of the keratin-degrading fungal community. The findings also encourage future studies on the artificially constructed keratin-degrading microbial consortia.


Asunto(s)
Ascomicetos/clasificación , Ascomicetos/aislamiento & purificación , Queratinas/metabolismo , Técnicas de Tipificación Micológica/métodos , Ascomicetos/crecimiento & desarrollo , China , Tipificación de Secuencias Multilocus , Micobioma/fisiología , Suelo , Microbiología del Suelo
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