50 research outputs found
MeRy-B: a web knowledgebase for the storage, visualization, analysis and annotation of plant NMR metabolomic profiles
<p>Abstract</p> <p>Background</p> <p>Improvements in the techniques for metabolomics analyses and growing interest in metabolomic approaches are resulting in the generation of increasing numbers of metabolomic profiles. Platforms are required for profile management, as a function of experimental design, and for metabolite identification, to facilitate the mining of the corresponding data. Various databases have been created, including organism-specific knowledgebases and analytical technique-specific spectral databases. However, there is currently no platform meeting the requirements for both profile management and metabolite identification for nuclear magnetic resonance (NMR) experiments.</p> <p>Description</p> <p>MeRy-B, the first platform for plant <sup>1</sup>H-NMR metabolomic profiles, is designed (<it>i</it>) to provide a knowledgebase of curated plant profiles and metabolites obtained by NMR, together with the corresponding experimental and analytical metadata, (<it>ii</it>) for queries and visualization of the data, (<it>iii</it>) to discriminate between profiles with spectrum visualization tools and statistical analysis, (<it>iv</it>) to facilitate compound identification. It contains lists of plant metabolites and unknown compounds, with information about experimental conditions, the factors studied and metabolite concentrations for several plant species, compiled from more than one thousand annotated NMR profiles for various organs or tissues.</p> <p>Conclusion</p> <p>MeRy-B manages all the data generated by NMR-based plant metabolomics experiments, from description of the biological source to identification of the metabolites and determinations of their concentrations. It is the first database allowing the display and overlay of NMR metabolomic profiles selected through queries on data or metadata. MeRy-B is available from <url>http://www.cbib.u-bordeaux2.fr/MERYB/index.php</url>.</p
Large-scale identification of human genes implicated in epidermal barrier function
Identification of genes expressed in epidermal granular keratinocytes by ORESTES, including a number that are highly specific for these cells
Being Pathogenic, Plastic, and Sexual while Living with a Nearly Minimal Bacterial Genome
Mycoplasmas are commonly described as the simplest self-replicating organisms, whose evolution was mainly characterized by genome downsizing with a proposed evolutionary scenario similar to that of obligate intracellular bacteria such as insect endosymbionts. Thus far, analysis of mycoplasma genomes indicates a low level of horizontal gene transfer (HGT) implying that DNA acquisition is strongly limited in these minimal bacteria. In this study, the genome of the ruminant pathogen Mycoplasma agalactiae was sequenced. Comparative genomic data and phylogenetic tree reconstruction revealed that âŒ18% of its small genome (877,438 bp) has undergone HGT with the phylogenetically distinct mycoides cluster, which is composed of significant ruminant pathogens. HGT involves genes often found as clusters, several of which encode lipoproteins that usually play an important role in mycoplasmaâhost interaction. A decayed form of a conjugative element also described in a member of the mycoides cluster was found in the M. agalactiae genome, suggesting that HGT may have occurred by mobilizing a related genetic element. The possibility of HGT events among other mycoplasmas was evaluated with the available sequenced genomes. Our data indicate marginal levels of HGT among Mycoplasma species except for those described above and, to a lesser extent, for those observed in between the two bird pathogens, M. gallisepticum and M. synoviae. This first description of large-scale HGT among mycoplasmas sharing the same ecological niche challenges the generally accepted evolutionary scenario in which gene loss is the main driving force of mycoplasma evolution. The latter clearly differs from that of other bacteria with small genomes, particularly obligate intracellular bacteria that are isolated within host cells. Consequently, mycoplasmas are not only able to subvert complex hosts but presumably have retained sexual competence, a trait that may prevent them from genome stasis and contribute to adaptation to new hosts
Bioinformatic analysis of ESTs collected by Sanger and pyrosequencing methods for a keystone forest tree species: oak
<p>Abstract</p> <p>Background</p> <p>The Fagaceae family comprises about 1,000 woody species worldwide. About half belong to the <it>Quercus </it>family. These oaks are often a source of raw material for biomass wood and fiber. Pedunculate and sessile oaks, are among the most important deciduous forest tree species in Europe. Despite their ecological and economical importance, very few genomic resources have yet been generated for these species. Here, we describe the development of an EST catalogue that will support ecosystem genomics studies, where geneticists, ecophysiologists, molecular biologists and ecologists join their efforts for understanding, monitoring and predicting functional genetic diversity.</p> <p>Results</p> <p>We generated 145,827 sequence reads from 20 cDNA libraries using the Sanger method. Unexploitable chromatograms and quality checking lead us to eliminate 19,941 sequences. Finally a total of 125,925 ESTs were retained from 111,361 cDNA clones. Pyrosequencing was also conducted for 14 libraries, generating 1,948,579 reads, from which 370,566 sequences (19.0%) were eliminated, resulting in 1,578,192 sequences. Following clustering and assembly using TGICL pipeline, 1,704,117 EST sequences collapsed into 69,154 tentative contigs and 153,517 singletons, providing 222,671 non-redundant sequences (including alternative transcripts). We also assembled the sequences using MIRA and PartiGene software and compared the three unigene sets. Gene ontology annotation was then assigned to 29,303 unigene elements. Blast search against the SWISS-PROT database revealed putative homologs for 32,810 (14.7%) unigene elements, but more extensive search with Pfam, Refseq_protein, Refseq_RNA and eight gene indices revealed homology for 67.4% of them. The EST catalogue was examined for putative homologs of candidate genes involved in bud phenology, cuticle formation, phenylpropanoids biosynthesis and cell wall formation. Our results suggest a good coverage of genes involved in these traits. Comparative orthologous sequences (COS) with other plant gene models were identified and allow to unravel the oak paleo-history. Simple sequence repeats (SSRs) and single nucleotide polymorphisms (SNPs) were searched, resulting in 52,834 SSRs and 36,411 SNPs. All of these are available through the Oak Contig Browser <url>http://genotoul-contigbrowser.toulouse.inra.fr:9092/Quercus_robur/index.html</url>.</p> <p>Conclusions</p> <p>This genomic resource provides a unique tool to discover genes of interest, study the oak transcriptome, and develop new markers to investigate functional diversity in natural populations.</p
Toward interoperable bioscience data
© The Author(s), 2012. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Nature Genetics 44 (2012): 121-126, doi:10.1038/ng.1054.To make full use of research data, the bioscience community needs to adopt technologies and reward mechanisms that support interoperability and promote the growth of an open 'data commoning' culture. Here we describe the prerequisites for data commoning and present an established and growing ecosystem of solutions using the shared 'Investigation-Study-Assay' framework to support that vision.The authors also acknowledge
the following funding sources in particular: UK
Biotechnology and Biological Sciences Research
Council (BBSRC) BB/I000771/1 to S.-A.S. and A.T.;
UK BBSRC BB/I025840/1 to S.-A.S.; UK BBSRC
BB/I000917/1 to D.F.; EU CarcinoGENOMICS
(PL037712) to J.K.; US National Institutes of Health
(NIH) 1RC2CA148222-01 to W.H. and the HSCI;
US MIRADA LTERS DEB-0717390 and Alfred P.
Sloan Foundation (ICoMM) to L.A.-Z.; Swiss Federal
Government through the Federal Office of Education
and Science (FOES) to L.B. and I.X.; EU Innovative
Medicines Initiative (IMI) Open PHACTS 115191 to
C.T.E.; US Department of Energy (DOE) DE-AC02-
06CH11357 and Arthur P. Sloan Foundation (2011-
6-05) to J.G.; UK BBSRC SysMO-DB2 BB/I004637/1
and BBG0102181 to C.G.; UK BBSRC BB/I000933/1
to C.S. and J.L.G.; UK MRC UD99999906 to J.L.G.;
US NIH R21 MH087336 (National Institute of Mental
Health) and R00 GM079953 (National Institute of
General Medical Science) to A.L.; NIH U54 HG006097
to J.C. and C.E.S.; Australian government through
the National Collaborative Research Infrastructure
Strategy (NCRIS); BIRN U24-RR025736 and BioScholar RO1-GM083871 to G.B. and the 2009 Super
Science initiative to C.A.S
Life on Arginine for Mycoplasma hominis: Clues from Its Minimal Genome and Comparison with Other Human Urogenital Mycoplasmas
Mycoplasma hominis is an opportunistic human mycoplasma. Two other pathogenic human species, M. genitalium and Ureaplasma parvum, reside within the same natural niche as M. hominis: the urogenital tract. These three species have overlapping, but distinct, pathogenic roles. They have minimal genomes and, thus, reduced metabolic capabilities characterized by distinct energy-generating pathways. Analysis of the M. hominis PG21 genome sequence revealed that it is the second smallest genome among self-replicating free living organisms (665,445 bp, 537 coding sequences (CDSs)). Five clusters of genes were predicted to have undergone horizontal gene transfer (HGT) between M. hominis and the phylogenetically distant U. parvum species. We reconstructed M. hominis metabolic pathways from the predicted genes, with particular emphasis on energy-generating pathways. The EmbdenâMeyerhoffâParnas pathway was incomplete, with a single enzyme absent. We identified the three proteins constituting the arginine dihydrolase pathway. This pathway was found essential to promote growth in vivo. The predicted presence of dimethylarginine dimethylaminohydrolase suggested that arginine catabolism is more complex than initially described. This enzyme may have been acquired by HGT from non-mollicute bacteria. Comparison of the three minimal mollicute genomes showed that 247 CDSs were common to all three genomes, whereas 220 CDSs were specific to M. hominis, 172 CDSs were specific to M. genitalium, and 280 CDSs were specific to U. parvum. Within these species-specific genes, two major sets of genes could be identified: one including genes involved in various energy-generating pathways, depending on the energy source used (glucose, urea, or arginine) and another involved in cytadherence and virulence. Therefore, a minimal mycoplasma cell, not including cytadherence and virulence-related genes, could be envisaged containing a core genome (247 genes), plus a set of genes required for providing energy. For M. hominis, this set would include 247+9 genes, resulting in a theoretical minimal genome of 256 genes
Minimum information about a protein affinity reagent (MIAPAR)
This is a proposal developed within the community as an important first step in formalizing standards in reporting the production and properties of protein binding reagents, such as antibodies, developed and sold for the identification and detection of specific proteins present in biological samples. It defines a checklist of required information, intended for use by producers of affinity reagents, qualitycontrol laboratories, users and databases. We envision that both commercial and freely available affinity reagents, as well as published studies using these reagents, could include a MIAPAR-compliant document describing the productâs properties with every available binding partner. This would enable the user or reader to make a fully informed evaluation of the validity of conclusions drawn using this reagent
Exploitation bioinformatique des relations entre mécanismes moléculaires et fonctions cellulaires
L'intĂ©gration des donnĂ©es biologiques est un des principaux dĂ©fis de la bioinformatique aujourd'hui. La mise Ă disposition de quantitĂ© importante de donnĂ©es concernant tous les niveaux d'organisation de la cellule, nĂ©cessite la mise en place de stratĂ©gies d'intĂ©gration pour rassembler toutes ces donnĂ©es, et ainsi mieux comprendre le fonctionnement de la cellule. Nous nouds sommes intĂ©ressĂ©s Ă l'exploitation du concept de voisinage pour reprĂ©senter et intĂ©grer des donnĂ©es biologiques. Dans un premier temps, notre travail met l'accent sur l'importance du choix de la reprĂ©sentation pour mener une intĂ©gration efficace. Notre Ă©tude sur la reprĂ©sentation du mĂ©tabolisme a montrĂ© que les modes Ă©lĂ©mentaires sont une alternative pertinente Ă la reprĂ©sentation classique sous forme de voies mĂ©taboliques. De plus, les modes Ă©lĂ©mentaires nous ont permis de trouver des routes mĂ©taboliques utilisĂ©es par la cellule en rĂ©ponse Ă divers stress. Nous avons Ă©galement exploitĂ© le voisinage dans une perspective de gĂ©nomique comparative. Nous avons cherchĂ© Ă dĂ©terminer si le voisinage d'expression peut ĂȘtre une signature pour les gĂšnes, et s'il peut ĂȘtre utilisĂ© pour caractĂ©riser des gĂšnees, en Ă©tablissant des Ă©quivalences entre des gĂ©nomes (orthologues ou gĂšnes fonctionnellement similaires). Les rĂ©sultats prĂ©sentĂ©s confirment l'intĂ©rĂȘt de l'exploration du voisinage, des gĂšnes et de leur produit, pour intĂ©grer des donnĂ©es hĂ©tĂ©rogĂšnes. L'efficacitĂ© de cette exploration est fortement liĂ©e au choix de la reprĂ©sentation des connaissances.Biological data integration is one of the major challenge in bioinformatics today. The availability of amounts of data concerning all the level of cell organisation, requires strategies of integration to bring together these data and thus better understand how the cell works. We have focused our work on the use of the concept of neighbourhood in order to represent and integrate data. First, our work emphasizes the importance of the choice of data representation for an efficient integration. Our study on metabolism representation shows that elementary modes are a relevant alternative to the classical representation of metabolism as metabolic pathways. Moreover, elementary modes have enabled us to find metabolic routes used by the cell in response to stressed. We have also used the neighbourhood in a new angle, the one of comparative genomics. We tested if expression neighbourhood of genes (set of genes with close expression profiles) can be a signature for genes, and if it can be used to define functional similarities between genes from different organisms. The work presented here, shows the interest of the exploration of gene and protein neighbourhood in order to integrate heterogeneous data. The efficiency of this exploration is highly related to the choice of knowledge representation.BORDEAUX2-BU SantĂ© (330632101) / SudocSudocFranceF