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1.
Int J Dev Biol ; 63(8-9-10): 563-572, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31840793

RESUMEN

After serving the Dictyostelium community for many years, the first version of dictyBase (Chisholm et al., 2006; Fey et al., 2006) was in need of a decisive update. The original dictyBase software was not adaptable to more current demands such as handling the import of large-scale data from recently sequenced genomes, keeping up with changes in the Gene Ontology (GO), or handling the automatic annotation of over 20,000 new strains. Therefore, we have embarked on a complete overhaul of dictyBase. The new infrastructure will allow the introduction of new data, such as more expressive GO annotations and Dictyostelium disease orthologs. A modern user interface aims to streamline usage of the database including orders from the Dicty Stock Center (DSC). New displays will allow novel views including the combination of data in two new tools. With the underlying software infrastructure now in place, dictyBase software engineers and curators are currently adding the user interfaces, new tools and content pages for the evolving version 2.0 of dictyBase. This review highlights the emerging status of the new dictyBase, updated pages and annotations that will soon be available in the new environment, an overview of our annotation procedures, and plans to involve the community in curation efforts.


Asunto(s)
Bancos de Muestras Biológicas , Bases de Datos Genéticas , Dictyostelium/genética , Dictyostelium/fisiología , Animales , Genes Protozoarios , Genoma de Protozoos , Almacenamiento y Recuperación de la Información , Internet , Mutación , Fenotipo , Plásmidos/genética , Programas Informáticos , Integración de Sistemas , Interfaz Usuario-Computador
2.
Genesis ; 53(8): 523-534, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26088819

RESUMEN

dictyBase is the model organism database for the social amoeba Dictyostelium discoideum and related species. The primary mission of dictyBase is to provide the biomedical research community with well-integrated high quality data, and tools that enable original research. Data presented at dictyBase is obtained from sequencing centers, groups performing high throughput experiments such as large-scale mutagenesis studies, and RNAseq data, as well as a growing number of manually added functional gene annotations from the published literature, including Gene Ontology, strain, and phenotype annotations. Through the Dicty Stock Center we provide the community with an impressive amount of annotated strains and plasmids. Recently, dictyBase accomplished a major overhaul to adapt an outdated infrastructure to the current technological advances, thus facilitating the implementation of innovative tools and comparative genomics. It also provides new strategies for high quality annotations that enable bench researchers to benefit from the rapidly increasing volume of available data. dictyBase is highly responsive to its users needs, building a successful relationship that capitalizes on the vast efforts of the Dictyostelium research community. dictyBase has become the trusted data resource for Dictyostelium investigators, other investigators or organizations seeking information about Dictyostelium, as well as educators who use this model system.


Asunto(s)
Curaduría de Datos/métodos , Bases de Datos Genéticas , Dictyostelium/genética , Programas Informáticos , Animales , Curaduría de Datos/normas , Dictyostelium/metabolismo , Estudios de Asociación Genética , Anotación de Secuencia Molecular/métodos , Anotación de Secuencia Molecular/normas
4.
Methods Mol Biol ; 983: 59-92, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23494302

RESUMEN

dictyBase (http://dictybase.org), the model organism database for Dictyostelium discoideum, includes the complete genome sequence and expression data for this organism. Relevant literature is integrated into the database, and gene models and functional annotation are manually curated from experimental results and comparative multigenome analyses. dictyBase has recently expanded to include the genome sequences of three additional Dictyostelids and has added new software tools to facilitate multigenome comparisons. The Dicty Stock Center, a strain and plasmid repository for Dictyostelium research, has relocated to Northwestern University in 2009. This allowed us integrating all Dictyostelium resources to better serve the research community. In this chapter, we will describe how to navigate the Web site and highlight some of our newer improvements.


Asunto(s)
Bases de Datos Genéticas , Dictyostelium/genética , Interfaz Usuario-Computador , Secuencia de Bases , Minería de Datos , Genoma de Protozoos , Anotación de Secuencia Molecular , Datos de Secuencia Molecular , Fenotipo , Proteínas Protozoarias/genética , Motor de Búsqueda , Programas Informáticos
5.
Database (Oxford) ; 2013: bas056, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23327936

RESUMEN

In many databases, biocuration primarily involves literature curation, which usually involves retrieving relevant articles, extracting information that will translate into annotations and identifying new incoming literature. As the volume of biological literature increases, the use of text mining to assist in biocuration becomes increasingly relevant. A number of groups have developed tools for text mining from a computer science/linguistics perspective, and there are many initiatives to curate some aspect of biology from the literature. Some biocuration efforts already make use of a text mining tool, but there have not been many broad-based systematic efforts to study which aspects of a text mining tool contribute to its usefulness for a curation task. Here, we report on an effort to bring together text mining tool developers and database biocurators to test the utility and usability of tools. Six text mining systems presenting diverse biocuration tasks participated in a formal evaluation, and appropriate biocurators were recruited for testing. The performance results from this evaluation indicate that some of the systems were able to improve efficiency of curation by speeding up the curation task significantly (∼1.7- to 2.5-fold) over manual curation. In addition, some of the systems were able to improve annotation accuracy when compared with the performance on the manually curated set. In terms of inter-annotator agreement, the factors that contributed to significant differences for some of the systems included the expertise of the biocurator on the given curation task, the inherent difficulty of the curation and attention to annotation guidelines. After the task, annotators were asked to complete a survey to help identify strengths and weaknesses of the various systems. The analysis of this survey highlights how important task completion is to the biocurators' overall experience of a system, regardless of the system's high score on design, learnability and usability. In addition, strategies to refine the annotation guidelines and systems documentation, to adapt the tools to the needs and query types the end user might have and to evaluate performance in terms of efficiency, user interface, result export and traditional evaluation metrics have been analyzed during this task. This analysis will help to plan for a more intense study in BioCreative IV.


Asunto(s)
Minería de Datos , Educación , Bases de Datos como Asunto , Documentación , Humanos , Programas Informáticos , Factores de Tiempo
6.
Nucleic Acids Res ; 41(Database issue): D676-83, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23172289

RESUMEN

dictyBase (http://dictybase.org) is the model organism database for the social amoeba Dictyostelium discoideum. This contribution provides an update on dictyBase that has been previously presented. During the past 3 years, dictyBase has taken significant strides toward becoming a genome portal for the whole Amoebozoa clade. In its latest release, dictyBase has scaled up to host multiple Dictyostelids, including Dictyostelium purpureum [Sucgang, Kuo, Tian, Salerno, Parikh, Feasley, Dalin, Tu, Huang, Barry et al.(2011) (Comparative genomics of the social amoebae Dictyostelium discoideum and Dictyostelium purpureum. Genome Biol., 12, R20)], Dictyostelium fasciculatum and Polysphondylium pallidum [Heidel, Lawal, Felder, Schilde, Helps, Tunggal, Rivero, John, Schleicher, Eichinger et al. (2011) (Phylogeny-wide analysis of social amoeba genomes highlights ancient origins for complex intercellular communication. Genome Res., 21, 1882-1891)]. The new release includes a new Genome Browser with RNAseq expression, interspecies Basic Local Alignment Search Tool alignments and a unified Basic Local Alignment Search Tool search for cross-species comparisons.


Asunto(s)
Bases de Datos Genéticas , Dictyosteliida/genética , Dictyostelium/genética , Genoma de Protozoos , Genómica , Internet , Proteínas Protozoarias/genética , ARN Protozoario/química , Alineación de Secuencia , Análisis de Secuencia de ARN , Interfaz Usuario-Computador
7.
Database (Oxford) ; 2012: bas040, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23160413

RESUMEN

WormBase, dictyBase and The Arabidopsis Information Resource (TAIR) are model organism databases containing information about Caenorhabditis elegans and other nematodes, the social amoeba Dictyostelium discoideum and related Dictyostelids and the flowering plant Arabidopsis thaliana, respectively. Each database curates multiple data types from the primary research literature. In this article, we describe the curation workflow at WormBase, with particular emphasis on our use of text-mining tools (BioCreative 2012, Workshop Track II). We then describe the application of a specific component of that workflow, Textpresso for Cellular Component Curation (CCC), to Gene Ontology (GO) curation at dictyBase and TAIR (BioCreative 2012, Workshop Track III). We find that, with organism-specific modifications, Textpresso can be used by dictyBase and TAIR to annotate gene productions to GO's Cellular Component (CC) ontology.


Asunto(s)
Arabidopsis/genética , Caenorhabditis elegans/genética , Minería de Datos/métodos , Bases de Datos Genéticas , Dictyostelium/genética , Publicaciones Periódicas como Asunto , Flujo de Trabajo , Acceso a la Información , Animales , Anotación de Secuencia Molecular
8.
Nucleic Acids Res ; 40(Database issue): D237-41, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22140108

RESUMEN

CharProtDB (http://www.jcvi.org/charprotdb/) is a curated database of biochemically characterized proteins. It provides a source of direct rather than transitive assignments of function, designed to support automated annotation pipelines. The initial data set in CharProtDB was collected through manual literature curation over the years by analysts at the J. Craig Venter Institute (JCVI) [formerly The Institute of Genomic Research (TIGR)] as part of their prokaryotic genome sequencing projects. The CharProtDB has been expanded by import of selected records from publicly available protein collections whose biocuration indicated direct rather than homology-based assignment of function. Annotations in CharProtDB include gene name, symbol and various controlled vocabulary terms, including Gene Ontology terms, Enzyme Commission number and TransportDB accession. Each annotation is referenced with the source; ideally a journal reference, or, if imported and lacking one, the original database source.


Asunto(s)
Bases de Datos de Proteínas , Anotación de Secuencia Molecular , Proteínas/química , Proteínas/genética , Proteínas/fisiología
9.
Water Environ Res ; 83(7): 627-35, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21790081

RESUMEN

Pilot-scale integrated fixed-film activated sludge (IFAS) and non-IFAS control systems were compared, with respect to overall performance and functional behaviors and microbial population composition in the attached and suspended phases. The suspended phases of the control and IFAS systems exhibited similar rates of ammonia consumption; the attached phase in the second aerobic IFAS reactor had significantly higher rates of ammonia consumption and nitrate production than any other biomass source, and the attached biomass from the first aerobic reactor had the lowest ammonia consumption rates. Quantitative polymerase chain reaction (qPCR) indicated the presence of the ammonia-oxidizing bacteria Nitrosomonas oligotropha and the nitrite-oxidizing bacteria Nitrospira spp. and Nitrobacter spp. Mathematical modeling and qPCR both indicated greater concentrations of nitrifiers in the attached phases of a downstream aerobic reactor relative to the upstream reactor, possibly because of increased competition from heterotrophs for space in the attached phase of the upstream aerobic reactor.


Asunto(s)
Biopelículas/crecimiento & desarrollo , Reacción en Cadena de la Polimerasa/métodos , Aguas del Alcantarillado/microbiología , Eliminación de Residuos Líquidos/métodos , Aerobiosis , Anaerobiosis , Bacterias/crecimiento & desarrollo , Proyectos Piloto , Purificación del Agua/métodos
10.
Nucleic Acids Res ; 39(Database issue): D620-4, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21087999

RESUMEN

dictyBase (http://www.dictybase.org), the model organism database for Dictyostelium, aims to provide the broad biomedical research community with well integrated, high quality data and tools for Dictyostelium discoideum and related species. dictyBase houses the complete genome sequence, ESTs, and the entire body of literature relevant to Dictyostelium. This information is curated to provide accurate gene models and functional annotations, with the goal of fully annotating the genome to provide a 'reference genome' in the Amoebozoa clade. We highlight several new features in the present update: (i) new annotations; (ii) improved interface with web 2.0 functionality; (iii) the initial steps towards a genome portal for the Amoebozoa; (iv) ortholog display; and (v) the complete integration of the Dicty Stock Center with dictyBase.


Asunto(s)
Bases de Datos Genéticas , Dictyostelium/genética , Amebozoos/genética , Genoma de Protozoos , Internet , Anotación de Secuencia Molecular , Proteínas Protozoarias/química , Proteínas Protozoarias/genética , Integración de Sistemas
11.
PLoS One ; 5(1): e8842, 2010 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-20107499

RESUMEN

Pseudomonas aeruginosa PA7 is a non-respiratory human isolate from Argentina that is multiresistant to antibiotics. We first sequenced gyrA, gyrB, parC, parE, ampC, ampR, and several housekeeping genes and found that PA7 is a taxonomic outlier. We report here the complete sequence of the 6,588,339 bp genome, which has only about 95% overall identity to other strains. PA7 has multiple novel genomic islands and a total of 51 occupied regions of genomic plasticity. These islands include antibiotic resistance genes, parts of transposons, prophages, and a pKLC102-related island. Several PA7 genes not present in PAO1 or PA14 are putative orthologues of other Pseudomonas spp. and Ralstonia spp. genes. PA7 appears to be closely related to the known taxonomic outlier DSM1128 (ATCC9027). PA7 lacks several virulence factors, notably the entire TTSS region corresponding to PA1690-PA1725 of PAO1. It has neither exoS nor exoU and lacks toxA, exoT, and exoY. PA7 is serotype O12 and pyoverdin type II. Preliminary proteomic studies indicate numerous differences with PAO1, some of which are probably a consequence of a frameshift mutation in the mvfR quorum sensing regulatory gene.


Asunto(s)
Genoma Bacteriano , Pseudomonas aeruginosa/genética , Antibacterianos/farmacología , Farmacorresistencia Microbiana/genética , Resistencia a Múltiples Medicamentos/genética , Pruebas de Sensibilidad Microbiana , Proteoma , Pseudomonas aeruginosa/clasificación , Pseudomonas aeruginosa/efectos de los fármacos , Pseudomonas aeruginosa/patogenicidad , Percepción de Quorum , Factores de Virulencia/genética
12.
Nucleic Acids Res ; 38(Database issue): D408-14, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19843611

RESUMEN

Pathema (http://pathema.jcvi.org) is one of the eight Bioinformatics Resource Centers (BRCs) funded by the National Institute of Allergy and Infectious Disease (NIAID) designed to serve as a core resource for the bio-defense and infectious disease research community. Pathema strives to support basic research and accelerate scientific progress for understanding, detecting, diagnosing and treating an established set of six target NIAID Category A-C pathogens: Category A priority pathogens; Bacillus anthracis and Clostridium botulinum, and Category B priority pathogens; Burkholderia mallei, Burkholderia pseudomallei, Clostridium perfringens and Entamoeba histolytica. Each target pathogen is represented in one of four distinct clade-specific Pathema web resources and underlying databases developed to target the specific data and analysis needs of each scientific community. All publicly available complete genome projects of phylogenetically related organisms are also represented, providing a comprehensive collection of organisms for comparative analyses. Pathema facilitates the scientific exploration of genomic and related data through its integration with web-based analysis tools, customized to obtain, display, and compute results relevant to ongoing pathogen research. Pathema serves the bio-defense and infectious disease research community by disseminating data resulting from pathogen genome sequencing projects and providing access to the results of inter-genomic comparisons for these organisms.


Asunto(s)
Infecciones Bacterianas/microbiología , Enfermedades Transmisibles/microbiología , Biología Computacional/métodos , Bases de Datos Genéticas , Secuencia de Aminoácidos , Animales , Infecciones Bacterianas/diagnóstico , Biología Computacional/tendencias , Genoma Bacteriano , Humanos , Almacenamiento y Recuperación de la Información/métodos , Internet , Datos de Secuencia Molecular , National Institute of Allergy and Infectious Diseases (U.S.) , Homología de Secuencia de Aminoácido , Programas Informáticos , Estados Unidos
13.
Appl Environ Microbiol ; 75(7): 2046-56, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19201974

RESUMEN

The complete genomes of three strains from the phylum Acidobacteria were compared. Phylogenetic analysis placed them as a unique phylum. They share genomic traits with members of the Proteobacteria, the Cyanobacteria, and the Fungi. The three strains appear to be versatile heterotrophs. Genomic and culture traits indicate the use of carbon sources that span simple sugars to more complex substrates such as hemicellulose, cellulose, and chitin. The genomes encode low-specificity major facilitator superfamily transporters and high-affinity ABC transporters for sugars, suggesting that they are best suited to low-nutrient conditions. They appear capable of nitrate and nitrite reduction but not N(2) fixation or denitrification. The genomes contained numerous genes that encode siderophore receptors, but no evidence of siderophore production was found, suggesting that they may obtain iron via interaction with other microorganisms. The presence of cellulose synthesis genes and a large class of novel high-molecular-weight excreted proteins suggests potential traits for desiccation resistance, biofilm formation, and/or contribution to soil structure. Polyketide synthase and macrolide glycosylation genes suggest the production of novel antimicrobial compounds. Genes that encode a variety of novel proteins were also identified. The abundance of acidobacteria in soils worldwide and the breadth of potential carbon use by the sequenced strains suggest significant and previously unrecognized contributions to the terrestrial carbon cycle. Combining our genomic evidence with available culture traits, we postulate that cells of these isolates are long-lived, divide slowly, exhibit slow metabolic rates under low-nutrient conditions, and are well equipped to tolerate fluctuations in soil hydration.


Asunto(s)
Bacterias/genética , Bacterias/aislamiento & purificación , ADN Bacteriano/genética , Genoma Bacteriano , Microbiología del Suelo , Antibacterianos/biosíntesis , Transporte Biológico , Metabolismo de los Hidratos de Carbono , Cianobacterias/genética , ADN Bacteriano/química , Hongos/genética , Macrólidos/metabolismo , Datos de Secuencia Molecular , Nitrógeno/metabolismo , Filogenia , Proteobacteria/genética , Análisis de Secuencia de ADN , Homología de Secuencia
14.
BMC Genomics ; 9: 597, 2008 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-19077236

RESUMEN

BACKGROUND: Acidithiobacillus ferrooxidans is a major participant in consortia of microorganisms used for the industrial recovery of copper (bioleaching or biomining). It is a chemolithoautrophic, gamma-proteobacterium using energy from the oxidation of iron- and sulfur-containing minerals for growth. It thrives at extremely low pH (pH 1-2) and fixes both carbon and nitrogen from the atmosphere. It solubilizes copper and other metals from rocks and plays an important role in nutrient and metal biogeochemical cycling in acid environments. The lack of a well-developed system for genetic manipulation has prevented thorough exploration of its physiology. Also, confusion has been caused by prior metabolic models constructed based upon the examination of multiple, and sometimes distantly related, strains of the microorganism. RESULTS: The genome of the type strain A. ferrooxidans ATCC 23270 was sequenced and annotated to identify general features and provide a framework for in silico metabolic reconstruction. Earlier models of iron and sulfur oxidation, biofilm formation, quorum sensing, inorganic ion uptake, and amino acid metabolism are confirmed and extended. Initial models are presented for central carbon metabolism, anaerobic metabolism (including sulfur reduction, hydrogen metabolism and nitrogen fixation), stress responses, DNA repair, and metal and toxic compound fluxes. CONCLUSION: Bioinformatics analysis provides a valuable platform for gene discovery and functional prediction that helps explain the activity of A. ferrooxidans in industrial bioleaching and its role as a primary producer in acidic environments. An analysis of the genome of the type strain provides a coherent view of its gene content and metabolic potential.


Asunto(s)
Acidithiobacillus/genética , Acidithiobacillus/metabolismo , Genoma Bacteriano , Biología Computacional , Genes Bacterianos , Microbiología Industrial , Datos de Secuencia Molecular , Familia de Multigenes
15.
PLoS Genet ; 4(7): e1000141, 2008 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-18654632

RESUMEN

We report here the sequencing and analysis of the genome of the nitrogen-fixing endophyte, Klebsiella pneumoniae 342. Although K. pneumoniae 342 is a member of the enteric bacteria, it serves as a model for studies of endophytic, plant-bacterial associations due to its efficient colonization of plant tissues (including maize and wheat, two of the most important crops in the world), while maintaining a mutualistic relationship that encompasses supplying organic nitrogen to the host plant. Genomic analysis examined K. pneumoniae 342 for the presence of previously identified genes from other bacteria involved in colonization of, or growth in, plants. From this set, approximately one-third were identified in K. pneumoniae 342, suggesting additional factors most likely contribute to its endophytic lifestyle. Comparative genome analyses were used to provide new insights into this question. Results included the identification of metabolic pathways and other features devoted to processing plant-derived cellulosic and aromatic compounds, and a robust complement of transport genes (15.4%), one of the highest percentages in bacterial genomes sequenced. Although virulence and antibiotic resistance genes were predicted, experiments conducted using mouse models showed pathogenicity to be attenuated in this strain. Comparative genomic analyses with the presumed human pathogen K. pneumoniae MGH78578 revealed that MGH78578 apparently cannot fix nitrogen, and the distribution of genes essential to surface attachment, secretion, transport, and regulation and signaling varied between each genome, which may indicate critical divergences between the strains that influence their preferred host ranges and lifestyles (endophytic plant associations for K. pneumoniae 342 and presumably human pathogenesis for MGH78578). Little genome information is available concerning endophytic bacteria. The K. pneumoniae 342 genome will drive new research into this less-understood, but important category of bacterial-plant host relationships, which could ultimately enhance growth and nutrition of important agricultural crops and development of plant-derived products and biofuels.


Asunto(s)
Genoma Bacteriano , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/patogenicidad , Fijación del Nitrógeno , Análisis de Secuencia de ADN , Animales , Animales no Consanguíneos , Secuencia de Bases , Cromosomas Bacterianos/química , Femenino , Klebsiella pneumoniae/metabolismo , Ratones , Ratones Endogámicos C3H , Datos de Secuencia Molecular , Virulencia
16.
J Bacteriol ; 188(19): 6841-50, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16980487

RESUMEN

The dimorphic prosthecate bacteria (DPB) are alpha-proteobacteria that reproduce in an asymmetric manner rather than by binary fission and are of interest as simple models of development. Prior to this work, the only member of this group for which genome sequence was available was the model freshwater organism Caulobacter crescentus. Here we describe the genome sequence of Hyphomonas neptunium, a marine member of the DPB that differs from C. crescentus in that H. neptunium uses its stalk as a reproductive structure. Genome analysis indicates that this organism shares more genes with C. crescentus than it does with Silicibacter pomeroyi (a closer relative according to 16S rRNA phylogeny), that it relies upon a heterotrophic strategy utilizing a wide range of substrates, that its cell cycle is likely to be regulated in a similar manner to that of C. crescentus, and that the outer membrane complements of H. neptunium and C. crescentus are remarkably similar. H. neptunium swarmer cells are highly motile via a single polar flagellum. With the exception of cheY and cheR, genes required for chemotaxis were absent in the H. neptunium genome. Consistent with this observation, H. neptunium swarmer cells did not respond to any chemotactic stimuli that were tested, which suggests that H. neptunium motility is a random dispersal mechanism for swarmer cells rather than a stimulus-controlled navigation system for locating specific environments. In addition to providing insights into bacterial development, the H. neptunium genome will provide an important resource for the study of other interesting biological processes including chromosome segregation, polar growth, and cell aging.


Asunto(s)
Alphaproteobacteria/genética , Caulobacter crescentus/genética , Genoma Bacteriano , Alphaproteobacteria/citología , Alphaproteobacteria/fisiología , Proteínas de la Membrana Bacteriana Externa/genética , Caulobacter crescentus/citología , Caulobacter crescentus/fisiología , Ciclo Celular/genética , Quimiotaxis/genética , Quimiotaxis/fisiología , ADN Bacteriano/química , ADN Bacteriano/genética , Flagelos/fisiología , Viabilidad Microbiana , Datos de Secuencia Molecular , Movimiento , Análisis de Secuencia de ADN , Homología de Secuencia , Transducción de Señal
17.
Proc Natl Acad Sci U S A ; 103(36): 13555-9, 2006 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-16938853

RESUMEN

Coastal aquatic environments are typically more highly productive and dynamic than open ocean ones. Despite these differences, cyanobacteria from the genus Synechococcus are important primary producers in both types of ecosystems. We have found that the genome of a coastal cyanobacterium, Synechococcus sp. strain CC9311, has significant differences from an open ocean strain, Synechococcus sp. strain WH8102, and these are consistent with the differences between their respective environments. CC9311 has a greater capacity to sense and respond to changes in its (coastal) environment. It has a much larger capacity to transport, store, use, or export metals, especially iron and copper. In contrast, phosphate acquisition seems less important, consistent with the higher concentration of phosphate in coastal environments. CC9311 is predicted to have differences in its outer membrane lipopolysaccharide, and this may be characteristic of the speciation of some cyanobacterial groups. In addition, the types of potentially horizontally transferred genes are markedly different between the coastal and open ocean genomes and suggest a more prominent role for phages in horizontal gene transfer in oligotrophic environments.


Asunto(s)
Adaptación Fisiológica , Ambiente , Genoma Bacteriano , Synechococcus/genética , Synechococcus/fisiología , Emparejamiento Base , Secuencia de Bases , Cromosomas Bacterianos , Mutación del Sistema de Lectura , Modelos Biológicos , Datos de Secuencia Molecular , Sistemas de Lectura Abierta , Operón , Filogenia , Mutación Puntual , ARN de Transferencia
18.
Genome Res ; 16(8): 1031-40, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16825665

RESUMEN

Clostridium perfringens is a Gram-positive, anaerobic spore-forming bacterium commonly found in soil, sediments, and the human gastrointestinal tract. C. perfringens is responsible for a wide spectrum of disease, including food poisoning, gas gangrene (clostridial myonecrosis), enteritis necroticans, and non-foodborne gastrointestinal infections. The complete genome sequences of Clostridium perfringens strain ATCC 13124, a gas gangrene isolate and the species type strain, and the enterotoxin-producing food poisoning strain SM101, were determined and compared with the published C. perfringens strain 13 genome. Comparison of the three genomes revealed considerable genomic diversity with >300 unique "genomic islands" identified, with the majority of these islands unusually clustered on one replichore. PCR-based analysis indicated that the large genomic islands are widely variable across a large collection of C. perfringens strains. These islands encode genes that correlate to differences in virulence and phenotypic characteristics of these strains. Significant differences between the strains include numerous novel mobile elements and genes encoding metabolic capabilities, strain-specific extracellular polysaccharide capsule, sporulation factors, toxins, and other secreted enzymes, providing substantial insight into this medically important bacterial pathogen.


Asunto(s)
Clostridium perfringens/genética , Genoma Bacteriano , Toxinas Bacterianas , Secuencia de Bases , ADN Bacteriano , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa
19.
Phys Med Rehabil Clin N Am ; 17(1): 49-72, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16517345

RESUMEN

The field of upper extremity prosthetics is a constantly changing arena as researchers and prosthetists strive to bridge the gap between prosthetic reality and upper limb physiology. With the further development of implantable neurologic sensing devices and targeted muscle innervation (discussed elsewhere in this issue), the challenge of limited input to control vast outputs promises to become a historical footnote in the future annals of upper limb prosthetics. Soon multidextrous terminal devices, such as that found in the iLimb system(Touch EMAS, Inc., Edinburgh, UK), will be a clinical reality (Fig. 22). Successful prosthetic care depends on good communication and cooperation among the surgeon, the amputee, the rehabilitation team, and the scientists harnessing the power of technology to solve real-life challenges. If the progress to date is any indication, amputees of the future will find their dreams limited only by their imagination.


Asunto(s)
Amputación Quirúrgica/rehabilitación , Miembros Artificiales , Amputación Quirúrgica/métodos , Brazo , Mano , Humanos , Satisfacción del Paciente , Diseño de Prótesis/métodos , Ajuste de Prótesis/métodos , Implantación de Prótesis/métodos , Recuperación de la Función
20.
PLoS Genet ; 2(2): e21, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16482227

RESUMEN

Anaplasma (formerly Ehrlichia) phagocytophilum, Ehrlichia chaffeensis, and Neorickettsia (formerly Ehrlichia) sennetsu are intracellular vector-borne pathogens that cause human ehrlichiosis, an emerging infectious disease. We present the complete genome sequences of these organisms along with comparisons to other organisms in the Rickettsiales order. Ehrlichia spp. and Anaplasma spp. display a unique large expansion of immunodominant outer membrane proteins facilitating antigenic variation. All Rickettsiales have a diminished ability to synthesize amino acids compared to their closest free-living relatives. Unlike members of the Rickettsiaceae family, these pathogenic Anaplasmataceae are capable of making all major vitamins, cofactors, and nucleotides, which could confer a beneficial role in the invertebrate vector or the vertebrate host. Further analysis identified proteins potentially involved in vacuole confinement of the Anaplasmataceae, a life cycle involving a hematophagous vector, vertebrate pathogenesis, human pathogenesis, and lack of transovarial transmission. These discoveries provide significant insights into the biology of these obligate intracellular pathogens.


Asunto(s)
Ehrlichia/genética , Ehrlichiosis/genética , Genómica/métodos , Animales , Biotina/metabolismo , Reparación del ADN , Ehrlichiosis/microbiología , Genoma , Humanos , Modelos Biológicos , Filogenia , Rickettsia/genética , Garrapatas
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