918 resultados para Metagenomic Library


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The lastyears declined the discovery of compounds to use in industrial and naturaldiversity has been the best supplier for novel genes, enzymes and compounds inhigh demand by the biotechnology industry. We know immense diversity of microorganisms,yet most remains unexplored. For these reason we use the metagenômica approach toinvestigate the potential of uncultured microorganisms. With this purpose weused the metagenomic library of from Eucalyptus spp. arboretum (EAA), wedid screening to found positive clone and them was submitted to the process of shotgun,the data obtained was submitted a bioinformatics analyses. Our results showsthe hypothesis of high unexplored microbial diversity of soil are able to foundnovel genes and metagenomic approach is and allowed to isolate novel genes and insilico analyses are essential part to identify a novel Inorganicpyrophosphatase (PPase) prediction indicated the novel gene operate as H+ pumps. Thissuggests that a special feature, our work in situ will be cloning thegene expression vector for subsequent kinetic characterization and crystallization.

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The screening for genes in metagenomic libraries from soil creates opportunities to explore the enormous genetic and metabolic diversity of microorganisms. Rivers are ecosystems with high biological diversity, but few were examined using the metagenomic approach. With this objective, a metagenomic library was constructed from DNA soil samples collected at three different points along the Jundiaí-river (Rio Grande do Norte-Brazil). The points sampled are from open area, rough terrain and with the direct incidence of sunlight. This library was analyzed functionally and based in sequence. For functional analysis Luria-Bertani solid medium (LB) with NaCl concentration varied from 0.17M to 0.85M was used for functional analysis. Positives clones resistant to hypersaline medium were obtained. The recombinant DNAs were extracted and transformed into Escherichia coli strain DH10B and survival curves were obtained for quantification of abiotic stress resistance. The sequences of clones were obtained and submitted to the BLASTX tool. Some clones were found to hypothetical proteins of microorganisms from both Archaea and Bacteria division. One of the clones showed a complete ORF with high similarity to glucose-6-phosphate isomerase which participates in the synthesis of glycerol pathway and serves as a compatible solute to balance the osmotic pressure inside and outside of cells. Subsequently, in order to identify genes encoding osmolytes or enzymes related halotolerance, environmental DNA samples from the river soil, from the water column of the estuary and ocean were collected and pyrosequenced. Sequences of osmolytes and enzymes of different microorganisms were obtained from the UniProt and used as RefSeqs for homology identification (TBLASTN) in metagenomic databases. The sequences were submitted to HMMER for the functional domains identification. Some enzymes were identified: alpha-trehalose-phosphate synthase, L-ectoina synthase (EctC), transaminase L-2 ,4-diaminobutyric acid (EctB), L-2 ,4-diaminobutyric acetyltransferase (EctA), L-threonine 3 dehydrogenase (sorbitol pathway), glycerol-3-phosphate dehydrogenase, inositol 3-phosphate dehydrogenase, chaperones, L-proline, glycine betaine binding ABC transporter, myo-inositol-1-phosphate synthase protein of proline simportadora / PutP sodium-and trehalose-6-phosphate phosphatase These proteins are commonly related to saline environments, however the identification of them in river environment is justified by the high salt concentration in the soil during prolonged dry seasons this river. Regarding the richness of the microbiota the river substrate has an abundance of halobacteria similar to the sea and more than the estuary. These data confirm the existence of a specialized response against salt stress by microorganisms in the environment of the Jundiaí river

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Tese (doutorado)—Universidade de Brasília, Instituto de Ciências Biológicas, Programa de Pós-Graduação em Biologia Molecular, 2016.

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Due to the wide diversity of unknown organisms in the environment, 99% of them cannot be grown in traditional culture medium in laboratories. Therefore, metagenomics projects are proposed to study microbial communities present in the environment, from molecular techniques, especially the sequencing. Thereby, for the coming years it is expected an accumulation of sequences produced by these projects. Thus, the sequences produced by genomics and metagenomics projects present several challenges for the treatment, storing and analysis such as: the search for clones containing genes of interest. This work presents the OCI Metagenomics, which allows defines and manages dynamically the rules of clone selection in metagenomic libraries, thought an algebraic approach based on process algebra. Furthermore, a web interface was developed to allow researchers to easily create and execute their own rules to select clones in genomic sequence database. This software has been tested in metagenomic cosmid library and it was able to select clones containing genes of interest. Copyright 2010 ACM.

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A Metagenomic Study of the Tick Midgut Daniel Yuan, B.S. Supervisory Professor : Steven J. Norris, Ph.D. Southern tick–associated rash illness (STARI) or Master’s disease is a Lyme-like illness that occurs following bites by Amblyomma americanum, the lone-star tick. Clinical symptoms include a bull’s eye rash similar to the erythema migrans lesions of Lyme disease, as well as fever and joint pains. Lyme disease is caused by Borrelia burgdorferi and related spirochetes. However, B. burgdorferi has not been detected in STARI patients, or in ticks in the South Central U.S. The causative agent of STARI has not been identified, although it was once thought to be caused by another Borrelia species, Borrelia lonestari. Furthermore, while adult A. americanum have up to a 5.6% Borrelia lonestari infection rate, the prevalence of all Borrelia species in Texas ticks as a whole is not known. Previous studies indicate that 6%-30% of Northern Ixodes scapularis ticks are infected by Borrelia burgdorferi while only 10% of Northern A. americanum and I. scapularis ticks are infected by Borrelia species. The first specific aim of this project was to determine the bacterial community that inhabits the midgut of Texas and Northeastern ticks by using high throughput metagenomic sequencing to sequence bacterial 16S rDNA. Through the use of massively parallel 454 sequencing, we were able to individually sequence hundreds of thousands of 16S rDNA regions of the bacterial flora from 133 ticks from the New York, Missouri and Texas. The presence of previously confirmed endosymbionts, specifically the Rickettsia spp. and Coxiella spp., that are commonly found in ticks were confirmed, as well as some highly prevalent genera that were previously undocumented. Furthermore, multiple pathogenic genera sequences were often found in the same tick, suggesting the possibility of co-infection of multiple pathogenic species. The second specific aim was to use Borrelia specific primers to screen 344 individual ticks from Missouri, Texas and the Northeast to determine the prevalence of Borrelia species in ticks. To screen for Borrelia species, two housekeeping genes, uvrA and recG, were selected as well as the 16S-23S rDNA intergenic spacer. Ticks from Missouri, Texas and New York were screened. None of the Missouri or Texas ticks tested positive for Borrelia spp. The rate of I. scapularis infection by B.burgdorferi is dependent on tick feeding activity as well as reservoir availability. B. burgdorferi is endemic in the Northeast, sometimes reported as highly present in over 50% of all I. scapularis ticks. 11.6% of all New York ticks were positive for a species of Borrelia, however only 6.9% of all New York ticks were positive for B. burgdorferi. Despite being significantly lower than 50%, the results still fall in line with previous reports of about the prevalence of B. burgdorferi. 1.5% of all Texas ticks were positive for a Borrelia species, specifically B. lonestari. While this study was unable to identify the causative agent for STARI, 454 sequencing was able to provide a tremendous insight into the bacterial flora and possible pathogenic species of both the I. scapularis and the A. americanum tick.

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Enhanced biological phosphorus removal (EBPR) is one of the best-studied microbially mediated industrial processes because of its ecological and economic relevance. Despite this, it is not well understood at the metabolic level. Here we present a metagenomic analysis of two lab-scale EBPR sludges dominated by the uncultured bacterium, Candidatus Accumulibacter phosphatis.'' The analysis sheds light on several controversies in EBPR metabolic models and provides hypotheses explaining the dominance of A. phosphatis in this habitat, its lifestyle outside EBPR and probable cultivation requirements. Comparison of the same species from different EBPR sludges highlights recent evolutionary dynamics in the A. phosphatis genome that could be linked to mechanisms for environmental adaptation. In spite of an apparent lack of phylogenetic overlap in the flanking communities of the two sludges studied, common functional themes were found, at least one of them complementary to the inferred metabolism of the dominant organism. The present study provides a much needed blueprint for a systems-level understanding of EBPR and illustrates that metagenomics enables detailed, often novel, insights into even well-studied biological systems.

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The situation in Europe concerning honeybees has in recent years become increasingly aggravated with steady decline in populations and/or catastrophic winter losses. This has largely been attributed to the occurrence of a variety of known and "unknown", emerging novel diseases. Previous studies have demonstrated that colonies often can harbour more than one pathogen, making identification of etiological agents with classical methods difficult. By employing an unbiased metagenomic approach, which allows the detection of both unexpected and previously unknown infectious agents, the detection of three viruses, Aphid Lethal Paralysis Virus (ALPV), Israel Acute Paralysis Virus (IAPV), and Lake Sinai Virus (LSV), in honeybees from Spain is reported in this article. The existence of a subgroup of ALPV with the ability to infect bees was only recently reported and this is the first identification of such a strain in Europe. Similarly, LSV appear to be a still unclassified group of viruses with unclear impact on colony health and these viruses have not previously been identified outside of the United States. Furthermore, our study also reveals that these bees carried a plant virus, Turnip Ringspot Virus (TuRSV), potentially serving as important vector organisms. Taken together, these results demonstrate the new possibilities opened up by high-throughput sequencing and metagenomic analysis to study emerging new diseases in domestic and wild animal populations, including honeybees.

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Two recent and related social developments of note for libraries are an upsurge in cultural participation enabled by Web 2.0 media and calls in government policy for enhanced innovation through education. Ironically, these have occurred at the same time that increasingly stringent copyright laws have restricted access to cultural content. Concepts of governmentality are used here to examine these tensions and contradictions. In particular, Foucault’s critique of the author figure and of freedom as part of the will to govern within liberal democratic societies is used to argue for better quality copyright education programs in school libraries and library information science education programs. For purposes of teaching and research, copyrights are defined as agglomerations of legal, economic, and educational discourses that enable and constrain what can and cannot be done with text in homes, schools, and library media centers. The article presents some possibilities for renewal of school libraries around copyright education and Creative Commons licensing.

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A complete change of career forces a seismic shift in every aspect of your life. From day one, you have to face the loss of long held beliefs, behaviours, the known world of self, and security. We came from professions that themselves are poles apart, and many of the challenges we faced entering the profession were the same: juggling full-time work, part time study, and family commitmemts, taking a pay cut, and loss of social life. But over a short period of time we both transitioned to our new profession successfully. so what make our successful transition possible?

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Evidence based practice (EBP) is recognised as a way of improving the quality of professional practice in many disciplines however its adoption within library and information sciences (LIS) has been gradual. The term was first introduced into the library and information profession‟s vocabulary a decade ago but an impediment to its uptake is the lack of clear understanding regarding how LIS practitioners understand the concept. Partridge, Thorpe, Edwards and Hallam (2007) identified the need to understand how LIS professionals experience or understand evidence based practice and proposed a model of four categories of experience to describe how LIS professionals experience EBP. This paper extends that framework by refining the different conceptions of evidence based practice and identifying relationships which exist between the categories of experience to provide a rich description of the EBP phenomenon. The paper also argues that the phrase “evidence based librarianship” and its variations be abandoned as practitioners do not see a distinction between EBP as applied to librarianship and information practice and industry specific jargon like “evidence based library and information practice”. This research will help current and future LIS practitioners, leaders and educators engage more actively in the establishment of an evidence based culture to improve library and information practice in Australia and internationally.

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An informed citizenry is essential to the effective functioning of democracy. In most modern liberal democracies, citizens have traditionally looked to the media as the primary source of information about socio-political matters. In our increasingly mediated world, it is critical that audiences be able to effectively and accurately use the media to meet their information needs. Media literacy, the ability to access, understand, evaluate and create media content is therefore a vital skill for a healthy democracy. The past three decades have seen the rapid expansion of the information environment, particularly through Internet technologies. It is obvious that media usage patterns have changed dramatically as a result. Blogs and websites are now popular sources of news and information, and are for some sections of the population likely to be the first, and possibly only, information source accessed when information is required. What are the implications for media literacy in such a diverse and changing information environment? The Alexandria Manifesto stresses the link between libraries, a well informed citizenry and effective governance, so how do these changes impact on libraries? This paper considers the role libraries can play in developing media literate communities, and explores the ways in which traditional media literacy training may be expanded to better equip citizens for new media technologies. Drawing on original empirical research, this paper highlights a key shortcoming of existing media literacy approaches: that of overlooking the importance of needs identification as an initial step in media selection. Self-awareness of one’s actual information need is not automatic, as can be witnessed daily at reference desks in libraries the world over. Citizens very often do not know what it is that they need when it comes to information. Without this knowledge, selecting the most appropriate information source from the vast range available becomes an uncertain, possibly even random, enterprise. Incorporating reference interview-type training into media literacy education, whereby the individual will develop the skills to interrogate themselves regarding their underlying information needs, will enhance media literacy approaches. This increased focus on the needs of the individual will also push media literacy education into a more constructivist methodology. The paper also stresses the importance of media literacy training for adults. Media literacy education received in school or even university cannot be expected to retain its relevance over time in our rapidly evolving information environment. Further, constructivist teaching approaches highlight the importance of context to the learning process, thus it may be more effective to offer media literacy education relating to news media use to adults, whilst school-based approaches focus on types of media more relevant to young people, such as entertainment media. Librarians are ideally placed to offer such community-based media literacy education for adults. They already understand, through their training and practice of the reference interview, how to identify underlying information needs. Further, libraries are placed within community contexts, where the everyday practice of media literacy occurs. The Alexandria Manifesto stresses the link between libraries, a well informed citizenry and effective governance. It is clear that libraries have a role to play in fostering media literacy within their communities.

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This paper looks at the challenges presented for the Australian Library and Information Association by its role as the professional association responsible for ensuring the quality of Australian library technician graduates. There is a particular focus on the issue of course recognition, where the Association's role is complicated by the need to work alongside the national quality assurance processes that have been established by the relevant technical education authorities. The paper describes the history of course recognition in Australia; examines the relationship between course recognition and other quality measures; and describes the process the Association has undertaken recently to ensure appropriate professional scrutiny in a changing environment of accountability.