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The first discrete mixed platinum(IV)-gold(III) oxoanion [PtIV2AuIII3O6((CH3)2AsO2)6]- (1) was synthesized by reaction of H2Pt(OH)6 with H[AuCl4] in a simple one-pot procedure in aqueous solution at pH 7 and comprises two equivalent PtIVO6(As(CH3)2)3 units which are linked by three square-planar AuIIIO4 units. Polyanion 1 could be isolated as a potassium or sodium salt in good yield, which were structurally characterized in the solid state by single-crystal XRD and TGA, and in solution by multinuclear (1H, 13C, 195Pt) NMR, indicating that polyanion 1 is stable in solution, which was confirmed by ESI-MS studies. The sodium salt of 1 undergoes a clean single-crystal-to-single-crystal (SCSC) structural transformation upon rehydration and dehydration.
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Sphingolipids are important biological mediators both in health and disease. We investigated the vascular effects of enhanced sphingomyelinase (SMase) activity in a mouse model of type 2 diabetes mellitus (T2DM) to gain an understanding of the signaling pathways involved. Myography was used to measure changes in the tone of the thoracic aorta after administration of 0.2 U/mL neutral SMase in the presence or absence of the thromboxane prostanoid (TP) receptor antagonist SQ 29,548 and the nitric oxide synthase (NOS) inhibitor L-NAME. In precontracted aortic segments of non-diabetic mice, SMase induced transient contraction and subsequent weak relaxation, whereas vessels of diabetic (Leprdb/Leprdb, referred to as db/db) mice showed marked relaxation. In the presence of the TP receptor antagonist, SMase induced enhanced relaxation in both groups, which was 3-fold stronger in the vessels of db/db mice as compared to controls and could not be abolished by ceramidase or sphingosine-kinase inhibitors. Co-administration of the NOS inhibitor L-NAME abolished vasorelaxation in both groups. Our results indicate dual vasoactive effects of SMase: TP-mediated vasoconstriction and NO-mediated vasorelaxation. Surprisingly, in spite of the general endothelial dysfunction in T2DM, the endothelial NOS-mediated vasorelaxant effect of SMase was markedly enhanced.
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Diabetes Mellitus Tipo 2 , Óxido Nítrico Sintasa de Tipo III , Ratones , Animales , Óxido Nítrico Sintasa de Tipo III/metabolismo , Vasodilatación , Esfingomielina Fosfodiesterasa/metabolismo , NG-Nitroarginina Metil Éster/farmacología , NG-Nitroarginina Metil Éster/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Óxido Nítrico/metabolismo , Modelos Animales de Enfermedad , Endotelio Vascular/metabolismo , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/metabolismoRESUMEN
When comparing the requirements of diverse journals to publish microbial 'Genome Reports,' we noticed that some mostly focus on benchmarking universal single-copy orthologs scores as a quality measure, while the exclusion of possible contaminating sequences from genomic resources and the possible misidentification of the target microbes receive less attention. To deal with these quality issues, we suggest that DNA barcodes that are widely accepted for the identification of the target microbe species should be extracted from newly reported genome resources and included in phylogenetic analyses to confirm the identity of the sequenced microorganisms before Genome Reports are published. This approach, applied, for example, by the journal IMA Fungus, largely prevents the misidentification of the microbes that are targeted for whole-genome sequencing (WGS). In addition, contig similarity values, including GC content, remapping coverage of WGS reads, and BLASTN searches against the National Center for Biotechnology Information nucleotide database, would also reveal contamination issues. The values of these two recommendations to improve the publication criteria for microbial Genome Reports in diverse journals are demonstrated here through analyses of a draft genome published in Molecular Plant-Microbe Interactions and then retracted due to contaminations. [Formula: see text] Copyright © 2023 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.
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Genoma , Genómica , Filogenia , Secuenciación Completa del Genoma , ADNRESUMEN
Powdery mildew fungi (Erysiphaceae), common obligate biotrophic pathogens of many plants, including important agricultural and horticultural crops, represent a monophyletic lineage within the Ascomycota. Within the Erysiphaceae, molecular phylogenetic relationships and DNA-based species and genera delimitations were up to now mostly based on nuclear ribosomal DNA (nrDNA) phylogenies. This is the first comprehensive genome-scale phylogenetic analysis of this group using 751 single-copy orthologous sequences extracted from 24 selected powdery mildew genomes and 14 additional genomes from Helotiales, the fungal order that includes the Erysiphaceae. Representative genomes of all powdery mildew species with publicly available whole-genome sequencing (WGS) data that were of sufficient quality were included in the analyses. The 24 powdery mildew genomes included in the analysis represented 17 species belonging to eight out of 19 genera recognized within the Erysiphaceae. The epiphytic genera, all but one represented by multiple genomes, belonged each to distinct, well-supported lineages. Three hemiendophytic genera, each represented by a single genome, together formed the hemiendophytic lineage. Out of the 14 other taxa from the Helotiales, Arachnopeziza araneosa, a saprobic species, was the only taxon that grouped together with the 24 genome-sequenced powdery mildew fungi in a monophyletic clade. The close phylogenetic relationship between the Erysiphaceae and Arachnopeziza was revealed earlier by a phylogenomic study of the Leotiomycetes. Further analyses of powdery mildew and Arachnopeziza genomes may discover signatures of the evolutionary processes that have led to obligate biotrophy from a saprobic way of life. A separate phylogeny was produced using the 18S, 5.8S, and 28S nrDNA sequences of the same set of powdery mildew specimens and compared to the genome-scale phylogeny. The nrDNA phylogeny was largely congruent to the phylogeny produced using 751 orthologs. This part of the study has revealed multiple contamination and other quality issues in some powdery mildew genomes. We recommend that the presence of 28S, internal transcribed spacer (ITS), and 18S nrDNA sequences in powdery mildew WGS datasets that are identical to those determined by Sanger sequencing should be used to assess the quality of assemblies, in addition to the commonly used Benchmarking Universal Single-Copy Orthologs (BUSCO) values.
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Noble rot is a favorable form of the interaction between grape (Vitis spp.) berries and the phytopathogenic fungus Botrytis cinerea. The transcriptome pattern of grapevine cells subject to natural noble rot development in the historic Hungarian Tokaj wine region has not been previously published. Furmint, a traditional white Tokaj variety suited to develop great quality noble rot was used in the experiments. Exploring a subset of the Furmint transcriptome redox and hormonal changes distinguishing between noble rot and bunch rot was revealed. Noble rot is defined by an early spike in abscisic acid (ABA) accumulation and a pronounced remodeling of ABA-related gene expression. Transcription of glutathione S-transferase isoforms is uniquely upregulated, whereas gene expression of some sectors of the antioxidative apparatus (e.g., catalases, carotenoid biosynthesis) is downregulated. These mRNA responses are lacking in berries exposed to bunch rot. Our results help to explain molecular details behind the fine and dynamic balance between noble rot and bunch rot development.
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BACKGROUND AND AIMS: Endogenous gaseous substances, such as NO and CO have been found to be effective vasodilators earlier. H2S has been identified as an additional one, however, for that substance both vasodilatory and vasoconstrictor responses have been described in different vascular territories. Our aim was to examine the effect of hydrogen sulfide on the tone of cerebral arterioles and some aspects of its mechanism. METHODS: The work was performed on excised rat anterior cerebral artery segments in vitro (diameter range 150-250 µm), using a pressure myograph system. We used NaHS as exogenous H2S donor, propargylglycine (PAG) to abolish the endogenous synthesis of hydrogen sulfide and 4,4'-Diisothiocyanatostilbene-2,2'-disulfonic acid (DIDS) to examine the potential role of Cl-/HCO3 - exchanger in the effects of H2S. The time course of the events after application of exogenous H2S was also evaluated. RESULTS: Our findings revealed that in these pathologically important vessels (1) endogenously produced H2S is not a vasodilator, but a moderate vasoconstrictor; (2) H2S has a biphasic effect: low concentrations are moderate vasoconstrictors, while at higher concentrations the initial contraction is followed by dilatation; (3) that vasodilation is prevented by DIDS (4,4'-Diisothiocyanatostilbene-2,2'-disulfonic acid disodium, an inhibitor of the Cl-/HCO3 - exchanger). CONCLUSION: These studies confirm that H2S should be taken into consideration as a modulator of cerebral arteriolar tone in mammals.
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Powdery mildew fungi (Erysiphaceae) are widespread obligate biotrophic plant pathogens. Thus, applying genetic and omics approaches to study these fungi remains a major challenge, particularly for species with hemiendophytic mycelium. These belong to a distinct phylogenetic lineage within the family Erysiphaceae. To date, only a single draft genome assembly is available for this clade, obtained for Leveillula taurica. Here, we generated the first draft genome assemblies of Pleochaeta shiraiana and Phyllactinia moricola, two tree-parasitic powdery mildew species with hemiendophytic mycelium, representing two genera that have not yet been investigated with genomics tools. The Pleochaeta shiraiana assembly was 96,769,103 bp in length and consisted of 14,447 scaffolds, and the Phyllactinia moricola assembly was 180,382,532 bp in length on 45,569 scaffolds. Together with the draft genome of L. taurica, these resources will be pivotal for understanding the molecular basis of the lifestyle of these fungi, which is unique within the family Erysiphaceae.
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Micelio , Enfermedades de las Plantas , Ascomicetos , Filogenia , Enfermedades de las Plantas/microbiologíaRESUMEN
Mycoparasitic fungi can be utilized as biocontrol agents (BCAs) of many plant pathogens. Deciphering the molecular mechanisms of mycoparasitism may improve biocontrol efficiency. This work reports the first functional genetic studies in Ampelomyces, widespread mycoparasites and BCAs of powdery mildew fungi, and a molecular genetic toolbox for future works. The nitrate reductase (euknr) gene was targeted to reveal the biological function of nitrate assimilation in Ampelomyces. These mycoparasites live in an apparently nitrate-free environment, i.e. inside the hyphae of powdery mildew fungi that lack any nitrate uptake and assimilation system. Homologous recombination-based gene knock-out (KO) was applied to eliminate the euknr gene using Agrobacterium tumefaciens-mediated transformation. Efficient KO of euknr was confirmed by PCR, and visible phenotype caused by loss of euknr was detected on media with different nitrogen sources. Mycoparasitic ability was not affected by knocking out euknr as a tested transformant readily parasitized Blumeria graminis and Podosphaera xanthii colonies on barley and cucumber, respectively, and the rate of mycoparasitism did not differ from the wild type. These results indicate that euknr is not involved in mycoparasitism. Dissimilatory processes, involvement in nitric oxide metabolism, or other, yet undiscovered processes may explain why a functional euknr is maintained in Ampelomyces.
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Ascomicetos , Nitratos , Ascomicetos/genética , Nitrato-Reductasa/genética , Enfermedades de las PlantasRESUMEN
Powdery mildews are among the most important plant pathogens worldwide, which are often attacked in the field by mycoparasitic fungi belonging to the genus Ampelomyces. The taxonomy of the genus Ampelomyces is unresolved, but well-supported molecular operational taxonomic units were repeatedly defined suggesting that the genus may include at least four to seven species. Some Ampelomyces strains were commercialized as biocontrol agents of crop pathogenic powdery mildews. However, the genomic mechanisms underlying their mycoparasitism are still poorly understood. To date, the draft genome of a single Ampelomyces strain, designated as HMLAC 05119, has been released. We report a high-quality, annotated hybrid draft genome assembly of A. quisqualis strain BRIP 72107, which, based on phylogenetic analyses, is not conspecific with HMLAC 05119. The constructed genome is 40.38 Mb in size, consisting of 24 scaffolds with an N50 of 2.99 Mb and 96.2% completeness. Our analyses revealed "bipartite" structure of Ampelomyces genomes, where GC-balanced genomic regions are interspersed by longer or shorter stretches of AT-rich regions. This is also a hallmark of many plant pathogenic fungi and provides further evidence for evolutionary affinity of Ampelomyces species to plant pathogenic fungi. The high-quality genome and annotation produced here provide an important resource for future genomic studies of mycoparasitisim to decipher molecular mechanisms underlying biocontrol processes and natural tritrophic interactions.
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Ascomicetos , Enfermedades de las Plantas , Ascomicetos/genética , Filogenia , Enfermedades de las Plantas/microbiología , Plantas/microbiologíaRESUMEN
A total of 26 Ampelomyces strains were isolated from mycelia of six different powdery mildew species that naturally infected their host plants in Japan. These were characterized based on morphological characteristics and sequences of ribosomal DNA internal transcribed spacer (rDNA-ITS) regions and actin gene (ACT) fragments. Collected strains represented six different genotypes and were accommodated in three different clades of the genus Ampelomyces. Morphology of the strains agreed with that of other Ampelomyces strains, but none of the examined characters were associated with any groups identified in the genetic analysis. Five powdery mildew species were inoculated with eight selected Ampelomyces strains to study their mycoparasitic activity. In the inoculation experiments, all Ampelomyces strains successfully infected all tested powdery mildew species, and showed no significant differences in their mycoparasitic activity as determined by the number of Ampelomyces pycnidia developed in powdery mildew colonies. The mycoparasitic interaction between the eight selected Ampelomyces strains and the tomato powdery mildew fungus (Pseudoidium neolycopersici strain KTP-03) was studied experimentally in the laboratory using digital microscopic technologies. It was documented that the spores of the mycoparasites germinated on tomato leaves and their hyphae penetrated the hyphae of Ps. neolycopersici. Ampelomyces hyphae continued their growth internally, which initiated the atrophy of the powdery mildew conidiophores 5 days post inoculation (dpi); caused atrophy 6 dpi; and complete collapse of the parasitized conidiphores 7 dpi. Ampelomyces strains produced new intracellular pycnidia in Ps. neolycopersici conidiophores ca. 8-10 dpi, when Ps. neolycopersici hyphae were successfully destroyed by the mycoparasitic strain. Mature pycnidia released spores ca. 10-14 dpi, which became the sources of subsequent infections of the intact powdery mildew hyphae. Mature pycnidia contained each ca. 200 to 1,500 spores depending on the mycohost species and Ampelomyces strain. This is the first detailed analysis of Ampelomyces strains isolated in Japan, and the first timing and quantification of mycoparasitism of Ps. neolycopersici on tomato by phylogenetically diverse Ampelomyces strains using digital microscopic technologies. The developed model system is useful for future biocontrol and ecological studies on Ampelomyces mycoparasites.
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Ascomicetos/aislamiento & purificación , Control Biológico de Vectores , Solanum lycopersicum/microbiología , Ascomicetos/clasificación , Ascomicetos/fisiología , Ascomicetos/ultraestructura , Genes Fúngicos , Especificidad del Huésped , Procesamiento de Imagen Asistido por Computador , Japón , Filogenia , Plantones/microbiología , Alineación de Secuencia , Homología de Secuencia de Ácido Nucleico , Especificidad de la Especie , Esporas Fúngicas/ultraestructura , Factores de Tiempo , Tricomas/microbiologíaRESUMEN
Powdery mildew is a significant threat to mungbean (Vigna radiata) and black gram (V. mungo) production across Australia and overseas. Although they have been present in Australia for at least six decades and are easily recognized in the field, the precise identification of the pathogens causing this disease has remained unclear. Our goal was to identify the powdery mildew species infecting mungbean, black gram, and wild mungbean (V. radiata ssp. sublobata) in Australia. The internal transcribed spacer (ITS) and large subunit sequences of the ribosomal DNA and/or morphology of 57 Australian specimens were examined. Mungbean and black gram were infected by two species: Podosphaera xanthii and a newly recognized taxon, Erysiphe vignae sp. nov. Wild mungbean was infected only with P. xanthii. Mungbean and black gram powdery mildew ITS sequences from China, India, and Taiwan revealed the presence of only P. xanthii on these crops despite controversial reports of an Erysiphe species on both crops in India. Sequence analyses indicated that the closest relative of E. vignae is E. diffusa, which infects soybean (Glycine max) and other plants. E. vignae did not infect soybean in cross-inoculation tests. In turn, E. diffusa from soybean infected black gram and provoked hypersensitive response in mungbean. The recognition of a second species, E. vignae, as another causal agent of mungbean and black gram powdery mildew in Australia may complicate plant breeding efforts and control of the disease with fungicide applications.
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Ascomicetos/patogenicidad , Erysiphe/patogenicidad , Enfermedades de las Plantas/microbiología , Vigna , Australia , Fitomejoramiento , Vigna/microbiologíaRESUMEN
A better understanding of the regulation of cerebrovascular circulation is of great importance because stroke and other cerebrovascular diseases represent a major concern in healthcare leading to millions of deaths yearly. The circulation of the central nervous system is regulated in a highly complex manner involving many local factors and hydrogen sulfide (H2S) is emerging as one such possible factor. Several lines of evidence support that H2S takes part in the regulation of vascular tone. Examinations using either exogenous treatment with H2S donor molecules or alterations to the enzymes that are endogenously producing this molecule revealed numerous important findings about its physiological and pathophysiological role. The great majority of these studies were performed on vessel segments derived from the systemic circulation but there are important observations made using cerebral vessels as well. The findings of these experimental works indicate that H2S is having a complex, pleiotropic effect on the vascular wall not only in the systemic circulation but in the cerebrovascular region as well. In this review, we summarize the most important experimental findings related to the potential role of H2S in the cerebral circulation.
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Circulación Cerebrovascular/fisiología , Endotelio Vascular/fisiología , Sulfuro de Hidrógeno/química , Transducción de Señal , Animales , Encéfalo/metabolismo , Dióxido de Carbono , Células Endoteliales/citología , Humanos , Ratones , Desarrollo de Músculos , Oxígeno , Presión , Ratas , Ratas Sprague-DawleyRESUMEN
Erysiphe necator populations, causing powdery mildew of grapes, have a complex genetic structure. Two genotypes, A and B, were identified in most vineyards across the world on the basis of fixed single nucleotide polymorphisms (SNPs) in several DNA regions. It was hypothesized that A populations overwinter as mycelia in grapevine buds, giving rise to so-called flag shoots in spring, and are more sensitive to fungicides than B populations, which overwinter as ascospores and become widespread later in the season. Other studies concluded that the biological significance of these genotypes is unclear. In the spring of 2015, there was a unique opportunity to collect E. necator samples from flag shoots in Hungary. The same grapevines were sampled in summer and autumn as well. A total of 182 samples were genotyped on the basis of ß-tubulin (TUB2), nuclear ribosomal DNA (nrDNA) intergenic spacer (IGS), and internal transcribed spacer (ITS) sequences. Genotypes of 56 samples collected in 2009-2011 were used for comparison. Genotype A was not detected at all in spring, and was present in only 19 samples in total, mixed with genotype B, and sometimes with another frequently found genotype, designated as B2. These results did not support the hypothesis about temporal isolation of the two genotypes and indicated that these are randomly distributed in vineyards.
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In contrast to Eurasia and North America, powdery mildews (Ascomycota, Erysiphales) are understudied in Australia. There are over 900 species known globally, with fewer than currently 60 recorded from Australia. Some of the Australian records are doubtful as the identifications were presumptive, being based on host plant-pathogen lists from overseas. The goal of this study was to provide the first comprehensive catalog of all powdery mildew species present in Australia. The project resulted in (i) an up-to-date list of all the taxa that have been identified in Australia based on published DNA barcode sequences prior to this study; (ii) the precise identification of 117 specimens freshly collected from across the country; and (iii) the precise identification of 30 herbarium specimens collected between 1975 and 2013. This study confirmed 42 species representing 10 genera, including two genera and 13 species recorded for the first time in Australia. In Eurasia and North America, the number of powdery mildew species is much higher. Phylogenetic analyses of powdery mildews collected from Acalypha spp. resulted in the transfer of Erysiphe acalyphae to Salmonomyces, a resurrected genus. Salmonomyces acalyphae comb. nov. represents a newly discovered lineage of the Erysiphales. Another taxonomic change is the transfer of Oidium ixodiae to Golovinomyces. Powdery mildew infections have been confirmed on 13 native Australian plant species in the genera Acacia, Acalypha, Cephalotus, Convolvulus, Eucalyptus, Hardenbergia, Ixodia, Jagera, Senecio, and Trema. Most of the causal agents were polyphagous species that infect many other host plants both overseas and in Australia. All powdery mildews infecting native plants in Australia were phylogenetically closely related to species known overseas. The data indicate that Australia is a continent without native powdery mildews, and most, if not all, species have been introduced since the European colonization of the continent.
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Powdery mildew of sweet pepper (Capsicum annuum) is an economically important disease. It is caused by Leveillula taurica, an obligate biotrophic ascomycete with a partly endophytic mycelium and haustoria, i.e., feeding structures formed in the mesophyll cells of infected host plant tissues. The molecular basis of its pathogenesis is largely unknown because genomic resources only exist for epiphytically growing powdery mildew fungi with haustoria formed exclusively in epidermal cells of their plant hosts. Here, we present the first reference genome assembly for an isolate of L. taurica isolated from sweet pepper in Hungary. The short read-based assembly consists of 23,599 contigs with a total length of 187.2 Mbp; the scaffold N50 is 13,899 kbp and N90 is 3,522 kbp; and the average GC content is 39.2%. We detected at least 92,881 transposable elements covering 55.5 Mbp (30.4%). BRAKER predicted 19,751 protein-coding gene models in this assembly. Our reference genome assembly of L. taurica is the first resource to study the molecular pathogenesis and evolution of a powdery mildew fungus with a partly endophytic lifestyle.
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Ascomicetos/genética , Capsicum/microbiología , Genoma Fúngico , Enfermedades de las Plantas/microbiología , Composición de Base , Mapeo Contig , Elementos Transponibles de ADNRESUMEN
Due to their comparatively small genome size and short generation time, fungi are exquisite model systems to study eukaryotic genome evolution. Powdery mildew fungi present an exceptional case because of their strict host dependency (termed obligate biotrophy) and the atypical size of their genomes (>100 Mb). This size expansion is largely due to the pervasiveness of transposable elements on 70% of the genome and is associated with the loss of multiple conserved ascomycete genes required for a free-living lifestyle. To date, little is known about the mechanisms that drove these changes, and information on ancestral powdery mildew genomes is lacking. We report genome analysis of the early-diverged and exclusively sexually reproducing powdery mildew fungus Parauncinula polyspora, which we performed on the basis of a natural leaf epiphytic metapopulation sample. In contrast to other sequenced species of this taxonomic group, the assembled P. polyspora draft genome is surprisingly small (<30 Mb), has a higher content of conserved ascomycete genes, and is sparsely equipped with transposons (<10%), despite the conserved absence of a common defense mechanism involved in constraining repetitive elements. We speculate that transposable element spread might have been limited by this pathogen's unique reproduction strategy and host features and further hypothesize that the loss of conserved ascomycete genes may promote the evolutionary isolation and host niche specialization of powdery mildew fungi. Limitations associated with this evolutionary trajectory might have been in part counteracted by the evolution of plastic, transposon-rich genomes and/or the expansion of gene families encoding secreted virulence proteins.IMPORTANCE Powdery mildew fungi are widespread and agronomically relevant phytopathogens causing major yield losses. Their genomes have disproportionately large numbers of mobile genetic elements, and they have experienced a significant loss of highly conserved fungal genes. In order to learn more about the evolutionary history of this fungal group, we explored the genome of an Asian oak tree pathogen, Parauncinula polyspora, a species that diverged early during evolution from the remaining powdery mildew fungi. We found that the P. polyspora draft genome is comparatively compact, has a low number of protein-coding genes, and, despite the absence of a dedicated genome defense system, lacks the massive proliferation of repetitive sequences. Based on these findings, we infer an evolutionary trajectory that shaped the genomes of powdery mildew fungi.
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Ascomicetos/genética , Regulación Fúngica de la Expresión Génica , Genes Fúngicos , Genoma Fúngico , Interacciones Huésped-Patógeno/genética , Enfermedades de las Plantas/microbiologíaRESUMEN
Powdery mildews, ubiquitous obligate biotrophic plant pathogens, are often attacked in the field by mycoparasitic fungi belonging to the genus Ampelomyces. Some Ampelomyces strains are commercialized biocontrol agents of crop pathogenic powdery mildews. Using Agrobacterium tumefaciens-mediated transformation (ATMT), we produced stable Ampelomyces transformants that constitutively expressed green fluorescent protein (GFP) to (i) improve the visualization of the mildew-Ampelomyces interaction and (ii) decipher the environmental fate of Ampelomyces fungi before and after acting as a mycoparasite. Detection of Ampelomyces structures, and especially hyphae, was greatly enhanced when diverse powdery mildew, leaf, and soil samples containing GFP transformants were examined with fluorescence microscopy compared with brightfield and differential interference contrast optics. We showed for the first time, to our knowledge, that Ampelomyces strains can persist up to 21 days on mildew-free host plant surfaces, where they can attack powdery mildew structures as soon as these appear after this period. As saprobes in decomposing, powdery mildew-infected leaves on the ground and also in autoclaved soil, Ampelomyces strains developed new hyphae but did not sporulate. These results indicate that Ampelomyces strains occupy a niche in the phyllosphere where they act primarily as mycoparasites of powdery mildews. Our work has established a framework for a molecular genetic toolbox for the genus Ampelomyces using ATMT.
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Ascomicetos/crecimiento & desarrollo , Proteínas Luminiscentes , Enfermedades de las Plantas , Agrobacterium tumefaciens , Proteínas Fluorescentes Verdes , Plantas/microbiologíaRESUMEN
A little known, unculturable ascomycete, referred to as Phyllachora ambrosiae, can destroy the inflorescences of Ambrosia artemisiifolia, an invasive agricultural weed and producer of highly allergenic pollen. The fungus often remains undetectable in ragweed populations. This work was conducted to understand its origin and pathogenesis, a prerequisite to consider its potential as a biocontrol agent. The methods used included light and transmission electron microscopy, nrDNA sequencing, phylogenetic analyses, artificial inoculations, and the examination of old herbarium and recent field specimens from Hungary, Korea, Ukraine and USA. The Eurasian and the North American specimens of this fungus were to represent two distinct, although closely related lineages that were only distantly related to other lineages within the Ascomycota. Consequently, we describe a new genus that includes Cryptophyllachora eurasiatica gen. et sp. nov. and C. ambrosiae comb. nov., respectively. The pathogenesis of C. eurasiatica was shown in A. artemisiifolia. No evidence was found for either seed-borne transmission or systemic infection. Two hypotheses were developed to explain the interaction between C. eurasiatica and A. artemisiifolia: (i) as yet undetected seed-borne transmissions and latent, systemic infections; or (ii) alternative hosts.
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Ambrosia/microbiología , Hongos/patogenicidad , Agricultura , ADN de Hongos/química , ADN de Hongos/aislamiento & purificación , ADN de Hongos/metabolismo , Hongos/clasificación , Hongos/genética , Microscopía Electrónica de Transmisión , Filogenia , Análisis de Secuencia de ADNRESUMEN
Our knowledge about hydrogen sulfide (H2S) significantly changed over the last two decades. Today it is considered as not only a toxic gas but also as a gasotransmitter with diverse roles in different physiological and pathophysiological processes. H2S has pleiotropic effects and its possible mechanisms of action involve (1) a reversible protein sulfhydration which can alter the function of the modified proteins similar to nitrosylation or phosphorylation; (2) direct antioxidant effects and (3) interaction with metalloproteins. Its effects on the human cardiovascular system are especially important due to the high prevalence of hypertension and myocardial infarction. The exact molecular targets that affect the vascular tone include the KATP channel, the endothelial nitric oxide synthase, the phosphodiesterase of the vascular smooth muscle cell and the cytochrome c oxidase among others and the combination of all these effects lead to the final result on the vascular tone. The relative role of each effect depends immensely on the used concentration and also on the used donor molecules but several other factors and experimental conditions could alter the final effect. The aim of the current review is to give a comprehensive summary of the current understanding on the mechanism of action and role of H2S in the regulation of vascular tone and to outline the obstacles that hinder the better understanding of its effects.
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Vasos Sanguíneos/fisiología , Sulfuro de Hidrógeno/metabolismo , Vasoconstricción/fisiología , Tejido Adiposo/metabolismo , Animales , Monóxido de Carbono/metabolismo , GMP Cíclico/metabolismo , Proteínas Quinasas Dependientes de GMP Cíclico/metabolismo , Complejo IV de Transporte de Electrones/metabolismo , Humanos , Redes y Vías Metabólicas , Óxido Nítrico Sintasa de Tipo III/metabolismo , Sistema Renina-Angiotensina/fisiologíaRESUMEN
INTRODUCTION AND AIM: The aim was to study the patients' adherence to some evidence-based medication (statins, beta blockers, platelet and RAS inhibitors) after suffering a myocardial infarction, and its impact on the outcome. METHOD: Retrospective observational cohort study was carried out from the data of the Hungarian Myocardial Infarction Registry between January 1, 2013, and December 31, 2014. 14,843 patients were alive at the end of hospital treatment, from them, those who had no myocardial infarction or death until 180 days were followed for one year. The adherence was defined as the proportion of time from the index event to the endpoint (or censoring) covered with prescription fillings. The endpoint was defined as death or reinfarction. Information on filling prescriptions for statins, platelet aggregation inhibitors, beta blockers and ARB/ACEI-inhibitors were obtained. Multivariate regression was used to model adherence and survival time. RESULTS: Good adherence (\>80%) to clopidogrel, statins, beta blockers, aspirin and ARB/ACEI was found in 64.9%, 54.4%, 36.5%, 31.7% and 64.0%, respectively. Patients treated with PCI during the index hospitalization had higher adherence to all medication (all p<0.01), except for beta-blocker (p = 0.484). Multivariate analysis confirmed that adherence to statins, to clopidogrel and ARB/ACEI-inhibitors was associated with 10.1% (p<0.0001), 10.4% (p = 0.0002) and 15.8% (p<0.0001) lower hazard of endpoint respectively for 25% points increase in adherence, controlling for age, sex, performing of PCI, 5 anamnestic data and date of index event. Adherence to aspirin and beta blockers was not significantly associated with the hazard. CONCLUSION: Higher adherence to some evidence-based medications was found to be associated with improved long term prognosis of the patients. Orv Hetil. 2017; 158(27): 1051-1057.