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1.
Nucleic Acids Res ; 50(D1): D765-D770, 2022 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-34634797

RESUMEN

The COVID-19 pandemic has seen unprecedented use of SARS-CoV-2 genome sequencing for epidemiological tracking and identification of emerging variants. Understanding the potential impact of these variants on the infectivity of the virus and the efficacy of emerging therapeutics and vaccines has become a cornerstone of the fight against the disease. To support the maximal use of genomic information for SARS-CoV-2 research, we launched the Ensembl COVID-19 browser; the first virus to be encompassed within the Ensembl platform. This resource incorporates a new Ensembl gene set, multiple variant sets, and annotation from several relevant resources aligned to the reference SARS-CoV-2 assembly. Since the first release in May 2020, the content has been regularly updated using our new rapid release workflow, and tools such as the Ensembl Variant Effect Predictor have been integrated. The Ensembl COVID-19 browser is freely available at https://covid-19.ensembl.org.


Asunto(s)
COVID-19/virología , Bases de Datos Genéticas , SARS-CoV-2/genética , Navegador Web , Coronaviridae/genética , Variación Genética , Genoma Viral , Humanos , Anotación de Secuencia Molecular
2.
Nucleic Acids Res ; 50(D1): D996-D1003, 2022 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-34791415

RESUMEN

Ensembl Genomes (https://www.ensemblgenomes.org) provides access to non-vertebrate genomes and analysis complementing vertebrate resources developed by the Ensembl project (https://www.ensembl.org). The two resources collectively present genome annotation through a consistent set of interfaces spanning the tree of life presenting genome sequence, annotation, variation, transcriptomic data and comparative analysis. Here, we present our largest increase in plant, metazoan and fungal genomes since the project's inception creating one of the world's most comprehensive genomic resources and describe our efforts to reduce genome redundancy in our Bacteria portal. We detail our new efforts in gene annotation, our emerging support for pangenome analysis, our efforts to accelerate data dissemination through the Ensembl Rapid Release resource and our new AlphaFold visualization. Finally, we present details of our future plans including updates on our integration with Ensembl, and how we plan to improve our support for the microbial research community. Software and data are made available without restriction via our website, online tools platform and programmatic interfaces (available under an Apache 2.0 license). Data updates are synchronised with Ensembl's release cycle.


Asunto(s)
Bases de Datos Genéticas , Genómica , Internet , Programas Informáticos , Animales , Biología Computacional , Genoma Bacteriano/genética , Genoma Fúngico/genética , Genoma de Planta/genética , Plantas/clasificación , Plantas/genética , Vertebrados/clasificación , Vertebrados/genética
3.
Nucleic Acids Res ; 49(D1): D884-D891, 2021 01 08.
Artículo en Inglés | MEDLINE | ID: mdl-33137190

RESUMEN

The Ensembl project (https://www.ensembl.org) annotates genomes and disseminates genomic data for vertebrate species. We create detailed and comprehensive annotation of gene structures, regulatory elements and variants, and enable comparative genomics by inferring the evolutionary history of genes and genomes. Our integrated genomic data are made available in a variety of ways, including genome browsers, search interfaces, specialist tools such as the Ensembl Variant Effect Predictor, download files and programmatic interfaces. Here, we present recent Ensembl developments including two new website portals. Ensembl Rapid Release (http://rapid.ensembl.org) is designed to provide core tools and services for genomes as soon as possible and has been deployed to support large biodiversity sequencing projects. Our SARS-CoV-2 genome browser (https://covid-19.ensembl.org) integrates our own annotation with publicly available genomic data from numerous sources to facilitate the use of genomics in the international scientific response to the COVID-19 pandemic. We also report on other updates to our annotation resources, tools and services. All Ensembl data and software are freely available without restriction.


Asunto(s)
Biología Computacional/métodos , Bases de Datos de Ácidos Nucleicos , Genómica/métodos , SARS-CoV-2/genética , Vertebrados/genética , Animales , COVID-19/epidemiología , COVID-19/virología , Humanos , Internet , Anotación de Secuencia Molecular/métodos , Pandemias , Vertebrados/clasificación
4.
Nucleic Acids Res ; 49(D1): D916-D923, 2021 01 08.
Artículo en Inglés | MEDLINE | ID: mdl-33270111

RESUMEN

The GENCODE project annotates human and mouse genes and transcripts supported by experimental data with high accuracy, providing a foundational resource that supports genome biology and clinical genomics. GENCODE annotation processes make use of primary data and bioinformatic tools and analysis generated both within the consortium and externally to support the creation of transcript structures and the determination of their function. Here, we present improvements to our annotation infrastructure, bioinformatics tools, and analysis, and the advances they support in the annotation of the human and mouse genomes including: the completion of first pass manual annotation for the mouse reference genome; targeted improvements to the annotation of genes associated with SARS-CoV-2 infection; collaborative projects to achieve convergence across reference annotation databases for the annotation of human and mouse protein-coding genes; and the first GENCODE manually supervised automated annotation of lncRNAs. Our annotation is accessible via Ensembl, the UCSC Genome Browser and https://www.gencodegenes.org.


Asunto(s)
COVID-19/prevención & control , Biología Computacional/métodos , Bases de Datos Genéticas , Genómica/métodos , Anotación de Secuencia Molecular/métodos , SARS-CoV-2/genética , Animales , COVID-19/epidemiología , COVID-19/virología , Epidemias , Humanos , Internet , Ratones , Seudogenes/genética , ARN Largo no Codificante/genética , SARS-CoV-2/metabolismo , SARS-CoV-2/fisiología , Transcripción Genética/genética
5.
Nucleic Acids Res ; 48(D1): D762-D767, 2020 01 08.
Artículo en Inglés | MEDLINE | ID: mdl-31642470

RESUMEN

WormBase (https://wormbase.org/) is a mature Model Organism Information Resource supporting researchers using the nematode Caenorhabditis elegans as a model system for studies across a broad range of basic biological processes. Toward this mission, WormBase efforts are arranged in three primary facets: curation, user interface and architecture. In this update, we describe progress in each of these three areas. In particular, we discuss the status of literature curation and recently added data, detail new features of the web interface and options for users wishing to conduct data mining workflows, and discuss our efforts to build a robust and scalable architecture by leveraging commercial cloud offerings. We conclude with a description of WormBase's role as a founding member of the nascent Alliance of Genome Resources.


Asunto(s)
Caenorhabditis elegans/genética , Bases de Datos Genéticas , Genes de Helminto , Animales , Minería de Datos , Genómica , Internet , Interfaz Usuario-Computador
6.
Nucleic Acids Res ; 48(D1): D689-D695, 2020 01 08.
Artículo en Inglés | MEDLINE | ID: mdl-31598706

RESUMEN

Ensembl Genomes (http://www.ensemblgenomes.org) is an integrating resource for genome-scale data from non-vertebrate species, complementing the resources for vertebrate genomics developed in the context of the Ensembl project (http://www.ensembl.org). Together, the two resources provide a consistent set of interfaces to genomic data across the tree of life, including reference genome sequence, gene models, transcriptional data, genetic variation and comparative analysis. Data may be accessed via our website, online tools platform and programmatic interfaces, with updates made four times per year (in synchrony with Ensembl). Here, we provide an overview of Ensembl Genomes, with a focus on recent developments. These include the continued growth, more robust and reproducible sets of orthologues and paralogues, and enriched views of gene expression and gene function in plants. Finally, we report on our continued deeper integration with the Ensembl project, which forms a key part of our future strategy for dealing with the increasing quantity of available genome-scale data across the tree of life.


Asunto(s)
Biología Computacional/métodos , Bases de Datos Genéticas , Variación Genética , Genoma Bacteriano , Genoma Fúngico , Genoma de Planta , Algoritmos , Animales , Caenorhabditis elegans/genética , Genómica , Internet , Anotación de Secuencia Molecular , Fenotipo , Plantas/genética , Valores de Referencia , Programas Informáticos , Interfaz Usuario-Computador
7.
J Proteome Res ; 20(5): 2851-2866, 2021 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-33890474

RESUMEN

Diaphorina citri is a vector of "Candidatus Liberibacter asiaticus" (CLas), associated with citrus greening disease. D. citri exhibit at least two color morphotypes, blue and non-blue, the latter including gray and yellow morphs. Blue morphs have a greater capacity for long-distance flight and transmit CLas less efficiently as compared to non-blue morphs. Differences in physiology and immunity between color morphs of the insect vector may influence disease epidemiology and biological control strategies. We evaluated the effect of CLas infection on color morph and sex-specific proteomic profiles of D. citri. Immunity-associated proteins were more abundant in blue morphs as compared to non-blue morphs but were upregulated at a higher magnitude in response to CLas infection in non-blue insects. To test for differences in color morph immunity, we measured two phenotypes: (1) survival of D. citri when challenged with the entomopathogenic fungus Beauveria bassiana and (2) microbial load of the surface and internal microbial communities. Non-blue color morphs showed higher mortality at four doses of B. bassinana, but no differences in microbial load were observed. Thus, color morph polyphenism is associated with two distinct proteomic immunity phenotypes in D. citri that may impact transmission of CLas and resistance to B. bassiana under some conditions.


Asunto(s)
Citrus , Hemípteros , Rhizobiaceae , Animales , Femenino , Insectos Vectores , Masculino , Enfermedades de las Plantas , Proteómica , Rhizobiaceae/genética
8.
Hum Mol Genet ; 28(13): 2271-2281, 2019 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-31220273

RESUMEN

Autism spectrum disorder (ASD) involves thousands of alleles in over 850 genes, but the current functional inference tools are not sufficient to predict phenotypic changes. As a result, the causal relationship of most of these genetic variants in the pathogenesis of ASD has not yet been demonstrated and an experimental method prioritizing missense alleles for further intensive analysis is crucial. For this purpose, we have designed a pipeline that uses Caenorhabditis elegans as a genetic model to screen for phenotype-changing missense alleles inferred from human ASD studies. We identified highly conserved human ASD-associated missense variants in their C. elegans orthologs, used a CRISPR/Cas9-mediated homology-directed knock-in strategy to generate missense mutants and analyzed their impact on behaviors and development via several broad-spectrum assays. All tested missense alleles were predicted to perturb protein function, but we found only 70% of them showed detectable phenotypic changes in morphology, locomotion or fecundity. Our findings indicate that certain missense variants in the C. elegans orthologs of human CACNA1D, CHD7, CHD8, CUL3, DLG4, GLRA2, NAA15, PTEN, SYNGAP1 and TPH2 impact neurodevelopment and movement functions, elevating these genes as candidates for future study into ASD. Our approach will help prioritize functionally important missense variants for detailed studies in vertebrate models and human cells.


Asunto(s)
Trastorno del Espectro Autista/genética , Caenorhabditis elegans/genética , Alelos , Animales , Sistemas CRISPR-Cas , Modelos Animales de Enfermedad , Fertilidad/genética , Estudios de Asociación Genética , Locomoción/genética , Mutación Missense , Trastornos del Neurodesarrollo/genética , Fenotipo
9.
Am J Physiol Heart Circ Physiol ; 321(5): H940-H947, 2021 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-34559582

RESUMEN

Right-sided heart failure is a common consequence of pulmonary arterial hypertension. Overloading the right ventricle results in right ventricular hypertrophy, which progresses to failure in a process characterized by impaired Ca2+ dynamics and force production that is linked with transverse (t)-tubule remodeling. This also unloads the left ventricle, which consequently atrophies. Experimental left-ventricular unloading can result in t-tubule remodeling, but it is currently unclear if this occurs in right-sided heart failure. In this work, we used a model of monocrotaline (MCT)-induced right heart failure in male rats, using confocal microscopy to investigate cellular remodeling of t-tubules, junctophilin-2 (JPH2), and ryanodine receptor-2 (RyR2). We examined remodeling across tissue anatomical regions of both ventricles: in trabeculae, papillary muscles, and free walls. Our analyses revealed that MCT hearts demonstrated a significant loss of t-tubule periodicity, disruption of the normal sarcomere striated pattern with JPH2 labeling, and also a disorganized striated pattern of RyR2, a feature not previously reported in right heart failure. Remodeling of JPH2 and RyR2 in the MCT heart was more pronounced in papillary muscles and trabeculae compared with free walls, particularly in the left ventricle. We find that these structures, commonly used as ex vivo muscle preparations, are more sensitive to the disease process.NEW & NOTEWORTHY In this work, we demonstrate that t-tubule remodeling occurs in the atrophied left ventricle as well as the overloaded right ventricle after right-side heart failure. Moreover, we identify that t-tubule remodeling in both ventricles is linked to sarcoplasmic reticulum remodeling as indicated by decreased labeling periodicity of both the Ca2+ release channel, RyR2, and the cardiac junction-forming protein, JPH2, that forms a link between the sarcoplasmic reticulum and sarcolemma. Studies developing treatments for right-sided heart failure should consider effects on both the right and left ventricle.


Asunto(s)
Insuficiencia Cardíaca/fisiopatología , Ventrículos Cardíacos/fisiopatología , Hipertrofia Ventricular Izquierda/fisiopatología , Sarcómeros/patología , Función Ventricular Izquierda , Función Ventricular Derecha , Remodelación Ventricular , Animales , Señalización del Calcio , Modelos Animales de Enfermedad , Insuficiencia Cardíaca/inducido químicamente , Insuficiencia Cardíaca/metabolismo , Insuficiencia Cardíaca/patología , Ventrículos Cardíacos/metabolismo , Ventrículos Cardíacos/patología , Hipertrofia Ventricular Izquierda/inducido químicamente , Hipertrofia Ventricular Izquierda/metabolismo , Hipertrofia Ventricular Izquierda/patología , Hipertrofia Ventricular Derecha/inducido químicamente , Hipertrofia Ventricular Derecha/metabolismo , Hipertrofia Ventricular Derecha/patología , Hipertrofia Ventricular Derecha/fisiopatología , Masculino , Proteínas de la Membrana/metabolismo , Monocrotalina , Ratas Wistar , Canal Liberador de Calcio Receptor de Rianodina/metabolismo , Sarcómeros/metabolismo
10.
J Proteome Res ; 19(2): 719-732, 2020 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-31885275

RESUMEN

"Candidatus Liberibacter asiaticus" (CLas) is the bacterium associated with the citrus disease Huanglongbing (HLB). Current CLas detection methods are unreliable during presymptomatic infection, and understanding CLas pathogenicity to help develop new detection techniques is challenging because CLas has yet to be isolated in pure culture. To understand how CLas affects citrus metabolism and whether infected plants produce systemic signals that can be used to develop improved detection techniques, leaves from Washington Navel orange (Citrus sinensis (L.) Osbeck) plants were graft-inoculated with CLas and longitudinally studied using transcriptomics (RNA sequencing), proteomics (liquid chromatography-tandem mass spectrometry), and metabolomics (proton nuclear magnetic resonance). Photosynthesis gene expression and protein levels were lower in infected plants compared to controls during late infection, and lower levels of photosynthesis proteins were identified as early as 8 weeks post-grafting. These changes coordinated with higher sugar concentrations, which have been shown to accumulate during HLB. Cell wall modification and degradation gene expression and proteins were higher in infected plants during late infection. Changes in gene expression and proteins related to plant defense were observed in infected plants as early as 8 weeks post-grafting. These results reveal coordinated changes in greenhouse navel leaves during CLas infection at the transcript, protein, and metabolite levels, which can inform of biomarkers of early infection.


Asunto(s)
Citrus sinensis , Citrus , Hemípteros , Rhizobiaceae , Animales , Citrus sinensis/genética , Liberibacter , Metabolómica , Enfermedades de las Plantas/genética , Proteómica , Rhizobiaceae/genética , Transcriptoma
11.
J Nat Prod ; 83(2): 296-304, 2020 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-32058711

RESUMEN

We report NMR- and MS-based structural characterizations of siderophores and related compounds from Beauveria bassiana (Balsamo-Crivelli) Vuillemin, including ten new chemical entities (2-4, 6-9, 11-12, and 15) and five known compounds, (1, 5, 10, 13, and 14). The siderophore mixture from ARSEF strain #2680 included two compounds in which N5-mevalonyl-N5-hydroxyornithine replaces both (2) or one (3) of the N5-anhydromevalonyl-N5-hydroxyornithine units of dimerumic acid (1). Mevalonolactone (14) was present as a degradation product of 2 and 3. ARSEF #2860 also produced compounds that have mannopyranose (5, 6) or 4-O-methyl-mannopyranose units (4, 7), two compounds (8, 9) that can be rationalized as 4-O-methyl-mannopyranosyl analogues of the esterifying acid moieties of metachelins A and B, respectively, and two probable decomposition products of 1, a nitro compound (11) and a formate (12). Beauverichelin A (15), a coprogen-type siderophore that represents the di-4-O-methyl-mannopyranosyl analogue of metachelin A, was detected in crude extracts of ARSEF #2860, but only in trace amounts. ARSEF strains #252 and #1955 yielded beauverichelin A in quantities that were sufficient for NMR analysis. Only the di- (1-7) and trihydroxamate (15) siderophores showed iron-binding activity in the CAS assay and, when ferrated, showed strong ESIMS signals consistent with 1:1 ligand/iron complexes.


Asunto(s)
Beauveria/química , Sideróforos/química , Animales , Dicetopiperazinas/química , Ácidos Hidroxámicos/química , Hierro/química , Hierro/metabolismo , Estructura Molecular , Nitrocompuestos/química , Sideróforos/aislamiento & purificación
12.
Nucleic Acids Res ; 46(D1): D869-D874, 2018 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-29069413

RESUMEN

WormBase (http://www.wormbase.org) is an important knowledge resource for biomedical researchers worldwide. To accommodate the ever increasing amount and complexity of research data, WormBase continues to advance its practices on data acquisition, curation and retrieval to most effectively deliver comprehensive knowledge about Caenorhabditis elegans, and genomic information about other nematodes and parasitic flatworms. Recent notable enhancements include user-directed submission of data, such as micropublication; genomic data curation and presentation, including additional genomes and JBrowse, respectively; new query tools, such as SimpleMine, Gene Enrichment Analysis; new data displays, such as the Person Lineage browser and the Summary of Ontology-based Annotations. Anticipating more rapid data growth ahead, WormBase continues the process of migrating to a cutting-edge database technology to achieve better stability, scalability, reproducibility and a faster response time. To better serve the broader research community, WormBase, with five other Model Organism Databases and The Gene Ontology project, have begun to collaborate formally as the Alliance of Genome Resources.


Asunto(s)
Bases de Datos Genéticas , Genoma , Nematodos/genética , Animales , Caenorhabditis/genética , Caenorhabditis elegans/genética , Curaduría de Datos , Minería de Datos , Conjuntos de Datos como Asunto , Modelos Animales de Enfermedad , Predicción , Ontología de Genes , Humanos , Almacenamiento y Recuperación de la Información , Platelmintos/genética , Edición , Interferencia de ARN , Alineación de Secuencia , Interfaz Usuario-Computador , Navegador Web
13.
Nucleic Acids Res ; 46(D1): D802-D808, 2018 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-29092050

RESUMEN

Ensembl Genomes (http://www.ensemblgenomes.org) is an integrating resource for genome-scale data from non-vertebrate species, complementing the resources for vertebrate genomics developed in the Ensembl project (http://www.ensembl.org). Together, the two resources provide a consistent set of programmatic and interactive interfaces to a rich range of data including genome sequence, gene models, transcript sequence, genetic variation, and comparative analysis. This paper provides an update to the previous publications about the resource, with a focus on recent developments and expansions. These include the incorporation of almost 20 000 additional genome sequences and over 35 000 tracks of RNA-Seq data, which have been aligned to genomic sequence and made available for visualization. Other advances since 2015 include the release of the database in Resource Description Framework (RDF) format, a large increase in community-derived curation, a new high-performance protein sequence search, additional cross-references, improved annotation of non-protein-coding genes, and the launch of pre-release and archival sites. Collectively, these changes are part of a continuing response to the increasing quantity of publicly-available genome-scale data, and the consequent need to archive, integrate, annotate and disseminate these using automated, scalable methods.


Asunto(s)
Archaea/genética , Bacterias/genética , Bases de Datos Genéticas , Bases de Datos de Proteínas , Eucariontes/genética , Genómica , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Minería de Datos , Predicción , Genoma , Anotación de Secuencia Molecular , ARN/genética , Interfaz Usuario-Computador
14.
Nucleic Acids Res ; 45(D1): D128-D134, 2017 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-27794554

RESUMEN

RNAcentral is a database of non-coding RNA (ncRNA) sequences that aggregates data from specialised ncRNA resources and provides a single entry point for accessing ncRNA sequences of all ncRNA types from all organisms. Since its launch in 2014, RNAcentral has integrated twelve new resources, taking the total number of collaborating database to 22, and began importing new types of data, such as modified nucleotides from MODOMICS and PDB. We created new species-specific identifiers that refer to unique RNA sequences within a context of single species. The website has been subject to continuous improvements focusing on text and sequence similarity searches as well as genome browsing functionality. All RNAcentral data is provided for free and is available for browsing, bulk downloads, and programmatic access at http://rnacentral.org/.


Asunto(s)
Bases de Datos de Ácidos Nucleicos , ARN no Traducido/química , Animales , Genómica , Humanos , Nucleótidos/química , Análisis de Secuencia de ARN , Especificidad de la Especie
15.
Nucleic Acids Res ; 44(D1): D774-80, 2016 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-26578572

RESUMEN

WormBase (www.wormbase.org) is a central repository for research data on the biology, genetics and genomics of Caenorhabditis elegans and other nematodes. The project has evolved from its original remit to collect and integrate all data for a single species, and now extends to numerous nematodes, ranging from evolutionary comparators of C. elegans to parasitic species that threaten plant, animal and human health. Research activity using C. elegans as a model system is as vibrant as ever, and we have created new tools for community curation in response to the ever-increasing volume and complexity of data. To better allow users to navigate their way through these data, we have made a number of improvements to our main website, including new tools for browsing genomic features and ontology annotations. Finally, we have developed a new portal for parasitic worm genomes. WormBase ParaSite (parasite.wormbase.org) contains all publicly available nematode and platyhelminth annotated genome sequences, and is designed specifically to support helminth genomic research.


Asunto(s)
Caenorhabditis elegans/genética , Bases de Datos Genéticas , Genoma de los Helmintos , Genómica , Nematodos/genética , Animales , Genes de Helminto , Anotación de Secuencia Molecular , Platelmintos/genética , Programas Informáticos
16.
Nucleic Acids Res ; 44(D1): D574-80, 2016 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-26578574

RESUMEN

Ensembl Genomes (http://www.ensemblgenomes.org) is an integrating resource for genome-scale data from non-vertebrate species, complementing the resources for vertebrate genomics developed in the context of the Ensembl project (http://www.ensembl.org). Together, the two resources provide a consistent set of programmatic and interactive interfaces to a rich range of data including reference sequence, gene models, transcriptional data, genetic variation and comparative analysis. This paper provides an update to the previous publications about the resource, with a focus on recent developments. These include the development of new analyses and views to represent polyploid genomes (of which bread wheat is the primary exemplar); and the continued up-scaling of the resource, which now includes over 23 000 bacterial genomes, 400 fungal genomes and 100 protist genomes, in addition to 55 genomes from invertebrate metazoa and 39 genomes from plants. This dramatic increase in the number of included genomes is one part of a broader effort to automate the integration of archival data (genome sequence, but also associated RNA sequence data and variant calls) within the context of reference genomes and make it available through the Ensembl user interfaces.


Asunto(s)
Bases de Datos Genéticas , Genoma Bacteriano , Genoma Fúngico , Genoma de Planta , Invertebrados/genética , Animales , Diploidia , Eucariontes/genética , Variación Genética , Genoma , Poliploidía , Alineación de Secuencia
17.
Appl Environ Microbiol ; 83(2)2017 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-27793824

RESUMEN

Nontyphoidal Salmonella strains are the main source of pathogenic bacterial contamination in the poultry industry. Recently, Salmonella enterica serovar Kentucky has been recognized as the most prominent serovar on carcasses in poultry-processing plants. Previous studies showed that flagella are one of the main factors that contribute to bacterial attachment to broiler skin. However, the precise role of flagella and the mechanism of attachment are unknown. There are two different flagellar subunits (fliC and fljB) expressed alternatively in Salmonella enterica serovars using phase variation. Here, by making deletions in genes encoding flagellar structural subunits (flgK, fliC, and fljB), and flagellar motor (motA), we were able to differentiate the role of flagella and their rotary motion in the colonization of broiler skin and cellular attachment. Utilizing a broiler skin assay, we demonstrated that the presence of FliC is necessary for attachment to broiler skin. Expression of the alternative flagellar subunit FljB enables Salmonella motility, but this subunit is unable to mediate tight attachment. Deletion of the flgK gene prevents proper flagellar assembly, making Salmonella significantly less adherent to broiler skin than the wild type. S Kentucky with deletions in all three structural genes, fliC, fljB, and flgK, as well as a flagellar motor mutant (motA), exhibited less adhesion and invasion of Caco-2 cells, while an fljB mutant was as adherent and invasive as the wild-type strain. IMPORTANCE: In this work, we answered clearly the role of flagella in S Kentucky attachment to the chicken skin and Caco-2 cells. We demonstrated that the presence of FliC is necessary for attachment to broiler skin. Expression of the alternative flagellar subunit FljB enables Salmonella motility, but this subunit is unable to mediate strong attachment. Deletion of the flgK gene prevents proper flagellar assembly, making Salmonella significantly less adherent to broiler skin than the wild type. S Kentucky with deletions in all three structural genes, fliC, fljB, and flgK, as well as a flagellar motor mutant (motA), exhibited less adhesion and invasion of Caco-2 cells, while an fljB mutant was as adherent and invasive as the wild-type strain. We expect these results will contribute to the understanding of the mechanisms of Salmonella attachment to food products.


Asunto(s)
Proteínas Bacterianas/genética , Pollos/microbiología , Salmonella enterica/fisiología , Animales , Proteínas Bacterianas/metabolismo , Células CACO-2 , Flagelina/genética , Flagelina/metabolismo , Humanos , Salmonella enterica/genética
18.
BMC Microbiol ; 17(1): 88, 2017 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-28381209

RESUMEN

BACKGROUND: Critical to the development of Salmonellosis in humans is the interaction of the bacterium with the epithelial lining of the gastrointestinal tract. Traditional scientific reasoning held type III secretion system (T3SS) as the virulence factor responsible for bacterial invasion. In this study, field-isolated Salmonella enterica serovar Kentucky and a known human pathogen Salmonella enterica serovar Typhimurium were mutated and evaluated for the invasion of human colorectal adenocarcinoma epithelial cells. RESULTS: S. enterica serovar Kentucky was shown to actively invade a eukaryotic monolayer, though at a rate that was significantly lower than Typhimurium. Additionally, strains mutated for T3SS formation were less invasive than the wild-type strains, but the decrease in invasion was not significant in Kentucky. CONCLUSIONS: Strains mutated for T3SS formation were able to initiate invasion of the eukaryotic monolayer to varying degrees based on strain, In the case of Kentucky, the mutated strain initiated invasion at a level that was not significantly different from the wild-type strain. A different result was observed for Typhimurium as the mutation significantly lowered the rate of invasion in comparison to the wild-type strain.


Asunto(s)
Salmonella enterica/clasificación , Salmonella enterica/genética , Salmonella enterica/patogenicidad , Salmonella typhimurium/clasificación , Salmonella typhimurium/genética , Salmonella typhimurium/patogenicidad , Serogrupo , Células CACO-2/microbiología , Técnicas de Cultivo de Célula , Recuento de Colonia Microbiana , ADN Bacteriano , Células Epiteliales/microbiología , Regulación Bacteriana de la Expresión Génica , Genes Bacterianos/genética , Humanos , Kentucky , Fenotipo , Infecciones por Salmonella/microbiología , Salmonella enterica/crecimiento & desarrollo , Salmonella typhimurium/crecimiento & desarrollo , Eliminación de Secuencia , Sistemas de Secreción Tipo III/genética , Sistemas de Secreción Tipo III/fisiología , Tropismo Viral/genética , Factores de Virulencia/genética
19.
J Proteome Res ; 15(5): 1670-84, 2016 05 06.
Artículo en Inglés | MEDLINE | ID: mdl-27052409

RESUMEN

This study aimed to identify the aluminum (Al)-induced proteomes in tomato (Solanum lycopersicum, "Micro-Tom") after long-term exposure to the stress factor. Plants were treated in Magnavaca's solution (pH 4.5) supplemented with 7.5 µM Al(3+) ion activity over a 4 month period beginning at the emergence of flower buds and ending when the lower mature leaves started to turn yellow. Proteomes were identified using a 8-plex isobaric tags for relative and absolute quantification (iTRAQ) labeling strategy followed by a two-dimensional (high- and low-pH) chromatographic separation and final generation of tandem mass spectrometry (MS/MS) spectra of tryptic peptides on an LTQ-Orbitrap Elite mass spectrometer. Principal component analysis revealed that the Al-treatment had induced systemic alterations in the proteomes from roots and leaves but not seed tissues. The significantly changed root proteins were shown to have putative functions in Al(3+) ion uptake and transportation, root development, and a multitude of other cellular processes. Changes in the leaf proteome indicate that the light reaction centers of photosynthetic machinery are the primary targets of Al-induced stress. Embryo and seed-coat tissues derived from Al-treated plants were enriched with stress proteins. The biological processes involving these Al-induced proteins concur with the physiological and morphological changes, such as the disturbance of mineral homeostasis (higher contents of Al, P, and Fe and reduced contents of S, Zn, and Mn in Al-treated compared to nontreated plants) in roots and smaller sizes of roots and the whole plants. More importantly, the identified significant proteins might represent a molecular mechanism for plants to develop toward establishing the Al tolerance and adaptation mechanism over a long period of stress treatment.


Asunto(s)
Adaptación Fisiológica , Aluminio/farmacología , Proteoma/efectos de los fármacos , Solanum lycopersicum/química , Aluminio/farmacocinética , Solanum lycopersicum/embriología , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/metabolismo , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/metabolismo , Proteoma/metabolismo , Proteómica/métodos , Semillas/efectos de los fármacos , Semillas/metabolismo
20.
BMC Microbiol ; 16(1): 168, 2016 07 29.
Artículo en Inglés | MEDLINE | ID: mdl-27473153

RESUMEN

BACKGROUND: Regardless of sanitation practices implemented to reduce Salmonella prevalence in poultry processing plants, the problem continues to be an issue. To gain an understanding of the attachment mechanism of Salmonella to broiler skin, a bioluminescent-based mutant screening assay was used. A random mutant library of a field-isolated bioluminescent strain of Salmonella enterica serovar Kentucky was constructed. Mutants' attachment to chicken skin was assessed in 96-well plates containing uniform 6 mm diameter pieces of circular chicken skin. After washing steps, mutants with reduced attachment were selected based on reduced bioluminescence, and transposon insertion sites were identified. RESULTS: Attachment attenuation was detected in transposon mutants with insertion in genes encoding flagella biosynthesis, lipopolysaccharide core biosynthesis protein, tryptophan biosynthesis, amino acid catabolism pathway, shikimate pathway, tricarboxylic acid (TCA) cycle, conjugative transfer system, multidrug resistant protein, and ATP-binding cassette (ABC) transporter system. In particular, mutations in S. Kentucky flagellar biosynthesis genes (flgA, flgC, flgK, flhB, and flgJ) led to the poorest attachment of the bacterium to skin. CONCLUSIONS: The current study indicates that attachment of Salmonella to broiler skin is a multifactorial process, in which flagella play an important role.


Asunto(s)
Pollos/microbiología , Salmonella enterica/genética , Serogrupo , Piel/microbiología , Subfamilia B de Transportador de Casetes de Unión a ATP/genética , Subfamilia B de Transportador de Casetes de Unión a ATP/metabolismo , Aminoácidos/metabolismo , Animales , Proteínas Bacterianas/biosíntesis , Proteínas Bacterianas/genética , Proteínas Portadoras/genética , Ciclo del Ácido Cítrico , Elementos Transponibles de ADN , ADN Bacteriano , Flagelos/genética , Flagelos/metabolismo , Flagelos/fisiología , Genes Bacterianos , Genoma Bacteriano , Lipopolisacáridos/biosíntesis , Lipopolisacáridos/genética , Redes y Vías Metabólicas , Mutación , Plásmidos , Enfermedades de las Aves de Corral/microbiología , Prevalencia , Salmonelosis Animal/microbiología , Salmonella enterica/crecimiento & desarrollo , Salmonella enterica/metabolismo , Triptófano/biosíntesis
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