RESUMEN
Invasive plant pathogenic fungi have a global impact, with devastating economic and environmental effects on crops and forests. Biosurveillance, a critical component of threat mitigation, requires risk prediction based on fungal lifestyles and traits. Recent studies have revealed distinct genomic patterns associated with specific groups of plant pathogenic fungi. We sought to establish whether these phytopathogenic genomic patterns hold across diverse taxonomic and ecological groups from the Ascomycota and Basidiomycota, and furthermore, if those patterns can be used in a predictive capacity for biosurveillance. Using a supervised machine learning approach that integrates phylogenetic and genomic data, we analyzed 387 fungal genomes to test a proof-of-concept for the use of genomic signatures in predicting fungal phytopathogenic lifestyles and traits during biosurveillance activities. Our machine learning feature sets were derived from genome annotation data of carbohydrate-active enzymes (CAZymes), peptidases, secondary metabolite clusters (SMCs), transporters, and transcription factors. We found that machine learning could successfully predict fungal lifestyles and traits across taxonomic groups, with the best predictive performance coming from feature sets comprising CAZyme, peptidase, and SMC data. While phylogeny was an important component in most predictions, the inclusion of genomic data improved prediction performance for every lifestyle and trait tested. Plant pathogenicity was one of the best-predicted traits, showing the promise of predictive genomics for biosurveillance applications. Furthermore, our machine learning approach revealed expansions in the number of genes from specific CAZyme and peptidase families in the genomes of plant pathogens compared to non-phytopathogenic genomes (saprotrophs, endo- and ectomycorrhizal fungi). Such genomic feature profiles give insight into the evolution of fungal phytopathogenicity and could be useful to predict the risks of unknown fungi in future biosurveillance activities.
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Ascomicetos , Genoma Fúngico , Humanos , Filogenia , Genoma Fúngico/genética , Ascomicetos/genética , Genómica , Péptido Hidrolasas/genética , Estilo de Vida , Aprendizaje AutomáticoRESUMEN
Mycoviruses are widespread and purportedly common throughout the fungal kingdom, although most are known from hosts in the two most recently diverged phyla, Ascomycota and Basidiomycota, together called Dikarya. To augment our knowledge of mycovirus prevalence and diversity in underexplored fungi, we conducted a large-scale survey of fungi in the earlier-diverging lineages, using both culture-based and transcriptome-mining approaches to search for RNA viruses. In total, 21.6% of 333 isolates were positive for RNA mycoviruses. This is a greater proportion than expected based on previous taxonomically broad mycovirus surveys and is suggestive of a strong phylogenetic component to mycoviral infection. Our newly found viral sequences are diverse, composed of double-stranded RNA, positive-sense single-stranded RNA (ssRNA), and negative-sense ssRNA genomes and include novel lineages lacking representation in the public databases. These identified viruses could be classified into 2 orders, 5 families, and 5 genera; however, half of the viruses remain taxonomically unassigned. Further, we identified a lineage of virus-like sequences in the genomes of members of Phycomycetaceae and Mortierellales that appear to be novel genes derived from integration of a viral RNA-dependent RNA polymerase gene. The two screening methods largely agreed in their detection of viruses; thus, we suggest that the culture-based assay is a cost-effective means to quickly assess whether a laboratory culture is virally infected. This study used culture collections and publicly available transcriptomes to demonstrate that mycoviruses are abundant in laboratory cultures of early-diverging fungal lineages. The function and diversity of mycoviruses found here will help guide future studies into mycovirus origins and ecological functions.IMPORTANCE Viruses are key drivers of evolution and ecosystem function and are increasingly recognized as symbionts of fungi. Fungi in early-diverging lineages are widespread, ecologically important, and comprise the majority of the phylogenetic diversity of the kingdom. Viruses infecting early-diverging lineages of fungi have been almost entirely unstudied. In this study, we screened fungi for viruses by two alternative approaches: a classic culture-based method and by transcriptome-mining. The results of our large-scale survey demonstrate that early-diverging lineages have higher infection rates than have been previously reported in other fungal taxa and that laboratory strains worldwide are host to infections, the implications of which are unknown. The function and diversity of mycoviruses found in these basal fungal lineages will help guide future studies into mycovirus origins and their evolutionary ramifications and ecological impacts.
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Virus Fúngicos/clasificación , Virus Fúngicos/genética , Hongos/virología , Genoma Viral , Filogenia , Evolución Molecular , Virus Fúngicos/aislamiento & purificación , Hongos/clasificación , Hongos/crecimiento & desarrollo , Enfermedades de las Plantas/microbiología , ARN Viral/genética , TranscriptomaRESUMEN
A 30-year-old woman with giant fusiform aneurysm of the azygos anterior cerebral artery is reported. Clipping of the aneurysm followed by modeling of pericallosal artery was performed in 2017. However, further enlargement of the aneurysm has been observed for subsequent 2 years. The patient underwent redo surgery with excision of the aneurysm followed by «hemi-bonnet bypass¼ procedure (anastomosis between superficial temporal artery and anterior cerebral artery with radial artery as an interposition graft). Literature data on reconstructive surgery in the treatment of complex pericallosal artery aneurysms are reviewed.
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Revascularización Cerebral , Aneurisma Intracraneal/cirugía , Adulto , Anastomosis Quirúrgica , Arteria Cerebral Anterior/cirugía , Femenino , Humanos , Arteria Radial/diagnóstico por imagen , Arteria Radial/cirugíaRESUMEN
Dothideomycetes is the largest class of kingdom Fungi and comprises an incredible diversity of lifestyles, many of which have evolved multiple times. Plant pathogens represent a major ecological niche of the class Dothideomycetes and they are known to infect most major food crops and feedstocks for biomass and biofuel production. Studying the ecology and evolution of Dothideomycetes has significant implications for our fundamental understanding of fungal evolution, their adaptation to stress and host specificity, and practical implications with regard to the effects of climate change and on the food, feed, and livestock elements of the agro-economy. In this study, we present the first large-scale, whole-genome comparison of 101 Dothideomycetes introducing 55 newly sequenced species. The availability of whole-genome data produced a high-confidence phylogeny leading to reclassification of 25 organisms, provided a clearer picture of the relationships among the various families, and indicated that pathogenicity evolved multiple times within this class. We also identified gene family expansions and contractions across the Dothideomycetes phylogeny linked to ecological niches providing insights into genome evolution and adaptation across this group. Using machine-learning methods we classified fungi into lifestyle classes with >95 % accuracy and identified a small number of gene families that positively correlated with these distinctions. This can become a valuable tool for genome-based prediction of species lifestyle, especially for rarely seen and poorly studied species.
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In this article we present the clinical case of 63 y.o. man with chronic occlusion of the right common, internal, and external carotid arteries, and critical stenosis of the left internal carotid artery, with complaints of muscle weakness and decreased sensitivity of the left limbs. The patient underwent a staged brain revascularization, the left carotid endarterectomy was performed at the first stage and followed by bonnet bypass, which consists in anastomosing the contralateral superficial temporal artery with the ipsilateral intracranial artery by autograft interposition. In the postoperative period, the patient's neurological symptoms regressed. This case demonstrates the possibility of using bonnet bypass as an alternative revascularization method in patients with cerebral blood circulation insufficiency.
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Estenosis Carotídea , Revascularización Cerebral , Endarterectomía Carotidea , Arterias Carótidas , Arteria Carótida Externa , Arteria Carótida Interna , Estenosis Carotídea/cirugía , Humanos , MasculinoRESUMEN
The fungal kingdom is too large to be discovered exclusively by classical genetics. The access to omics data opens a new opportunity to study the diversity within the fungal kingdom and how adaptation to new environments shapes fungal metabolism. Genomes are the foundation of modern science but their quality is crucial when analysing omics data. In this study, we demonstrate how one gold-standard genome can improve functional prediction across closely related species to be able to identify key enzymes, reactions and pathways with the focus on primary carbon metabolism. Based on this approach we identified alternative genes encoding various steps of the different sugar catabolic pathways, and as such provided leads for functional studies into this topic. We also revealed significant diversity with respect to genome content, although this did not always correlate to the ability of the species to use the corresponding sugar as a carbon source.
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We classified the genes encoding carbohydrate-active enzymes (CAZymes) in 17 sequenced genomes representing 16 evolutionarily diverse Aspergillus species. We performed a phylogenetic analysis of the encoding enzymes, along with experimentally characterized CAZymes, to assign molecular function to the Aspergilli CAZyme families and subfamilies. Genome content analysis revealed that the numbers of CAZy genes per CAZy family related to plant biomass degradation follow closely the taxonomic distance between the species. On the other hand, growth analysis showed almost no correlation between the number of CAZyme genes and the efficiency in polysaccharide utilization. The exception is A. clavatus where a reduced number of pectinolytic enzymes can be correlated with poor growth on pectin. To gain detailed information on the enzymes used by Aspergilli to breakdown complex biomass, we conducted exoproteome analysis by mass spectrometry. These results showed that Aspergilli produce many different enzymes mixtures in the presence of sugar beet pulp and wheat bran. Despite the diverse enzyme mixtures produced, species of section Nigri, A. aculeatus, A. nidulans and A. terreus, produce mixtures of enzymes with activities that are capable of digesting all the major polysaccharides in the available substrates, suggesting that they are capable of degrading all the polysaccharides present simultaneously. For the other Aspergilli, typically the enzymes produced are targeted to a subset of polysaccharides present, suggesting that they can digest only a subset of polysaccharides at a given time.
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Many organisms benefit from being pre-adapted to niches shaped by human activity, and have successfully invaded man-made habitats. One such species is the dry rot fungus Serpula lacrymans, which has a wide distribution in buildings in temperate and boreal regions, where it decomposes coniferous construction wood. Comparative genomic analyses and growth experiments using this species and its wild relatives revealed that S. lacrymans evolved a very effective brown rot decay compared to its wild relatives, enabling an extremely rapid decay in buildings under suitable conditions. Adaptations in intracellular transport machineries promoting hyphal growth, and nutrient and water transport may explain why it is has become a successful invader of timber in houses. Further, we demonstrate that S. lacrymans has poor combative ability in our experimental setup, compared to other brown rot fungi. In sheltered indoor conditions, the dry rot fungus may have limited encounters with other wood decay fungi compared to its wild relatives. Overall, our analyses indicate that the dry rot fungus is an ecological specialist with poor combative ability against other fungi.
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Adaptación Biológica/genética , Basidiomycota/fisiología , Materiales de Construcción/microbiología , Ecosistema , Variación Genética , Madera/microbiología , Basidiomycota/genética , Humanos , Análisis de Secuencia de ADNRESUMEN
Hydrophobins are small secreted proteins that are present as several gene copies in most fungal genomes. Their properties are now well understood: they are amphiphilic and assemble at hydrophilic/hydrophobic interfaces. However, their physiological functions remain largely unexplored, especially within mycorrhizal fungi. In this study, we identified hydrophobin genes and analysed their distribution in eight mycorrhizal genomes. We then measured their expression levels in three different biological conditions (mycorrhizal tissue vs. free-living mycelium, organic vs. mineral growth medium and aerial vs. submerged growth). Results confirmed that the size of the hydrophobin repertoire increased in the terminal orders of the fungal evolutionary tree. Reconciliation analysis predicted that in 41% of the cases, hydrophobins evolved from duplication events. Whatever the treatment and the fungal species, the pattern of expression of hydrophobins followed a reciprocal function, with one gene much more expressed than others from the same repertoire. These most-expressed hydrophobin genes were also among the most expressed of the whole genome, which suggests that they play a role as structural proteins. The fine-tuning of the expression of hydrophobin genes in each condition appeared complex because it differed considerably between species, in a way that could not be explained by simple ecological traits. Hydrophobin gene regulation in mycorrhizal tissue as compared with free-living mycelium, however, was significantly associated with a calculated high exposure of hydrophilic residues.
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Proteínas Fúngicas/genética , Duplicación de Gen , Genoma Fúngico , Micorrizas/genética , Genómica , MicelioRESUMEN
Endosymbiosis of bacteria by eukaryotes is a defining feature of cellular evolution. In addition to well-known bacterial origins for mitochondria and chloroplasts, multiple origins of bacterial endosymbiosis are known within the cells of diverse animals, plants and fungi. Early-diverging lineages of terrestrial fungi harbor endosymbiotic bacteria belonging to the Burkholderiaceae. We sequenced the metagenome of the soil-inhabiting fungus Mortierella elongata and assembled the complete circular chromosome of its endosymbiont, Mycoavidus cysteinexigens, which we place within a lineage of endofungal symbionts that are sister clade to Burkholderia. The genome of M. elongata strain AG77 features a core set of primary metabolic pathways for degradation of simple carbohydrates and lipid biosynthesis, while the M. cysteinexigens (AG77) genome is reduced in size and function. Experiments using antibiotics to cure the endobacterium from the host demonstrate that the fungal host metabolism is highly modulated by presence/absence of M. cysteinexigens. Independent comparative phylogenomic analyses of fungal and bacterial genomes are consistent with an ancient origin for M. elongata - M. cysteinexigens symbiosis, most likely over 350 million years ago and concomitant with the terrestrialization of Earth and diversification of land fungi and plants.
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Burkholderiaceae/genética , Metabolismo de los Hidratos de Carbono/genética , Genoma Bacteriano/genética , Genoma Fúngico/genética , Metabolismo de los Lípidos/genética , Mortierella/genética , Simbiosis/genética , Animales , Secuencia de Bases , Burkholderiaceae/metabolismo , Burkholderiaceae/fisiología , Evolución Molecular , Redes y Vías Metabólicas/genética , Metagenoma/genética , Mortierella/aislamiento & purificación , Mortierella/fisiología , Filogenia , Análisis de Secuencia de ADNAsunto(s)
Procedimientos Quirúrgicos Cardíacos , Esternotomía/efectos adversos , Infección de la Herida Quirúrgica , Procedimientos Quirúrgicos Cardíacos/efectos adversos , Procedimientos Quirúrgicos Cardíacos/métodos , Humanos , Medición de Riesgo , Factores de Riesgo , Esternotomía/métodos , Infección de la Herida Quirúrgica/etiología , Infección de la Herida Quirúrgica/microbiología , Infección de la Herida Quirúrgica/prevención & controlRESUMEN
Marinesco bodies were discovered in the human substantia nigra neurons in 1902. However, relationships these intranuclear inclusions with other cell nuclear structures remains obscured yet. The aim of the present study was to investigate morphological and cytochemical peculiarities of these ubiquitin-immunopositive intranuclear bodies in neurons of the human substantia nigra and the character of their relationships with the nucleolus using light microscopy, immunocytochemistry, and confocal laser microscopy. It has been established that up to 20 % of the neurons of the substantia nigra contain ubiquitin-immunopositive Marinesco bodies. Only a third of them were closely adjacent to the nucleolus. Using a method of silver impregnation of argentophilic proteins associated with nuclear organizer, the lack of the argentophilic proteins typical for the nucleolus has been shown in the Marinesco bodies. We have found some specific ubiquitin-positive structures in the nuclei of neurons in addition to Marinesco bodies. These structures having less than 1 µm in size are supposedly the initial forms of the Marinesco bodies. Confocal laser microscopy has revealed two types of the ubiquitin-immunopositive intranuclear bodies--with high and low immunofluorescence, while the latter shows heterogeneity in distribution of the immunopositive product. With the use of a fluorescent dye SYTOX Green, the presence of DNA has been revealed in the Marinesco bodies. The absence of the peripheral zone of heterochromatin and poor perception of toluidine blue in combination with the DNA presence and loss of argentophilic proteins strongly suggest significant structural and chemical differences between Marinesco bodies and nucleoli and argue against the view that the revealed bodies may be changed nucleoli.
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Núcleo Celular/metabolismo , Heterocromatina/metabolismo , Neuronas/metabolismo , Proteínas Nucleares/metabolismo , Sustancia Negra/metabolismo , Ubiquitina/metabolismo , Adulto , Anciano , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Neuronas/citología , Sustancia Negra/citologíaRESUMEN
Distribution of iron in the substantia nigra of the human brain (10 men and women aged 27-78 years) was studied using Perls' histochemical method. Iron ions were demonstrated in the nigral neuropil and melanin-containing neurons. For the first time the nuclei of some neurons were found to contain iron accumulations. The intranuclear iron inclusions correspond to the nucleolus according to their sharp outline and sizes. Detection of iron in the neuronal nucleolus may contribute to the understanding of mechanisms of iron neurotoxicity for nigral dopaminergic neurons.
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Nucléolo Celular/química , Hierro/análisis , Neuronas/química , Sustancia Negra/química , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neurópilo/química , Sustancia Negra/citologíaRESUMEN
Antibodies AB(60-72) and AB(80-92) against two immune-dominant epitopes of photoreceptor Ca(2+)-binding protein recoverin, 60-DPKAYAQHVFRSF-72 and 80-LDFKEYVIALHMT-92, which can be exposed in a Ca(2+)-dependent manner, were obtained. The presence of AB(60-72) or AB(80-92) results in a slight increase in Ca(2+)-affinity of recoverin and does not affect significantly a Ca(2+)-myristoyl switch mechanism of the protein. However in the presence of AB(60-72) or AB(80-92) recoverin loses its ability to interact with rhodopsin kinase and consequently to perform a function of Ca(2+)-sensitive inhibitor of rhodopsin phosphorylation in photoreceptor cells.
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Calcio/metabolismo , Epítopos Inmunodominantes/química , Epítopos Inmunodominantes/inmunología , Recoverina/química , Recoverina/metabolismo , Rodopsina/metabolismo , Secuencia de Aminoácidos , Animales , Anticuerpos/inmunología , Especificidad de Anticuerpos , Bovinos , Quinasa 1 del Receptor Acoplado a Proteína-G/antagonistas & inhibidores , Epítopos Inmunodominantes/metabolismo , Ácido Mirístico/metabolismo , Fosforilación/efectos de los fármacos , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/inmunología , Inhibidores de Proteínas Quinasas/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , Recoverina/inmunología , Recoverina/farmacologíaRESUMEN
Time-lapse fluorescence microscopy imaging has rapidly evolved in the past decade and has opened new avenues for studying intracellular processes in vivo. Such studies generate vast amounts of noisy image data that cannot be analyzed efficiently and reliably by means of manual processing. Many popular tracking techniques exist but often fail to yield satisfactory results in the case of high object densities, high noise levels, and complex motion patterns. Probabilistic tracking algorithms, based on Bayesian estimation, have recently been shown to offer several improvements over classical approaches, by better integration of spatial and temporal information, and the possibility to more effectively incorporate prior knowledge about object dynamics and image formation. In this paper, we extend our previous work in this area and propose an improved, fully automated particle filtering algorithm for the tracking of many subresolution objects in fluorescence microscopy image sequences. It involves a new track management procedure and allows the use of multiple dynamics models. The accuracy and reliability of the algorithm are further improved by applying marginalization concepts. Experiments on synthetic as well as real image data from three different biological applications clearly demonstrate the superiority of the algorithm compared to previous particle filtering solutions.
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Algoritmos , Biopolímeros/análisis , Interpretación de Imagen Asistida por Computador/métodos , Microscopía Fluorescente/métodos , Reconocimiento de Normas Patrones Automatizadas/métodos , Inteligencia Artificial , Aumento de la Imagen/métodos , Técnicas de Sonda Molecular , Movimiento (Física) , Análisis Numérico Asistido por Computador , Tamaño de la Partícula , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Procesamiento de Señales Asistido por ComputadorRESUMEN
Lactic acid-producing bacteria are associated with various plant and animal niches and play a key role in the production of fermented foods and beverages. We report nine genome sequences representing the phylogenetic and functional diversity of these bacteria. The small genomes of lactic acid bacteria encode a broad repertoire of transporters for efficient carbon and nitrogen acquisition from the nutritionally rich environments they inhabit and reflect a limited range of biosynthetic capabilities that indicate both prototrophic and auxotrophic strains. Phylogenetic analyses, comparison of gene content across the group, and reconstruction of ancestral gene sets indicate a combination of extensive gene loss and key gene acquisitions via horizontal gene transfer during the coevolution of lactic acid bacteria with their habitats.