Made available in DSpace on 2014-12-17T14:10:25Z (GMT). No. of bitstreams: 1 AbinadabeJM_DISSERT.pdf: 2202389 bytes, checksum: c6fb8bcc059666158ed3af8030f88987 (MD5) Previous issue date: 2012-07-19 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / Industrial activities, oil spills and its derivatives, as well as the incomplete combustion of fossil fuels have caused a great accumulation of hydrocarbons in the environment. The number of microorganisms on the planet is estimated at 1030 and prokaryotes the most abundant. They colonized diverse environments for thousands of years, including those considered extreme and represent an untapped source of metabolic and genetic diversity with a large biotechnological potential. It is also known that certain microorganisms have the enzymatic capacity to degrade petroleum hydrocarbons and, in many ecosystems, there is an indigenous community capable of performing this function. The metagenomic has revolutionized the microbiology allowing access uncultured microbial communities, being a powerful tool for elucidation of their ecological functions and metabolic profiles, as well as for identification of new biomolecules. Thus, this study applied metagenomic approaches not only for functional selection of genes involved in biodegradation and emulsification processes of the petroleum-derived hydrocarbons, but also to describe the taxonomic and metabolic composition of two metagenomes from aquatic microbiome. We analyzed 123.116 (365 ? 118 bp) and 127.563 sequences (352 ? 120 bp) of marine and estuarine metagenomes, respectively. Eight clones were found, four involved in the petroleum biodegradation and four were able to emulsify kerosene indicating their abilities in biosurfactants synthesis. Therefore, the metagenomic analyses performed were efficient not only in the search of bioproducts of biotechnological interest and in the analysis of the functional and taxonomic profile of the metagenomes studied as well / Atividades industriais, derramamentos de petr?leo e seus derivados, bem como a combust?o incompleta de combust?veis f?sseis t?m causado um grande ac?mulo de hidrocarbonetos no meio ambiente. O n?mero de microrganismos no planeta ? estimado em 1030, sendo os procariotos os mais abundantes. Eles colonizaram diversos ambientes durante milhares de anos, incluindo aqueles considerados extremos e representam uma fonte inexplorada de diversidade gen?tica e metab?lica com um grande potencial biotecnol?gico. Sabe-se que muitos microrganismos possuem vias metab?licas complexas atuando na biodegrada??o de hidrocarbonetos derivados de petr?leo e, em muitos ecossistemas, existe uma comunidade aut?ctone capaz de realizar essa fun??o. A metagen?mica tem revolucionado a Microbiologia permitindo o acesso ?s comunidades microbianas n?o cultiv?veis, sendo uma potente ferramenta para elucida??o de suas fun??es ecol?gicas, dos perfis metab?licos, bem como para identifica??o de novas biomol?culas. Assim, o presente estudo aplicou abordagens metagen?micas n?o apenas para sele??o funcional de genes envolvidos nos processos de biodegrada??o e biossurfacta??o de hidrocarbonetos derivados do petr?leo, mas tamb?m para descri??o da composi??o taxon?mica e metab?lica de dois metagenomas de microbiota aqu?tica. Foram analisadas 123.116 (365 ? 118 pb) e 127.563 sequ?ncias (352 ? 120 pb) dos metagenomas marinho e estuarino, respectivamente. Oito clones foram encontrados, sendo quatro envolvidos na biodegrada??o de petr?leo e quatro capazes de emulsificar querosene, indicando a habilidade de sintetizar biossurfactantes. Portanto, as an?lises metagen?micas realizadas foram eficientes n?o apenas na busca de bioprodutos de interesse biotecnol?gico como tamb?m na an?lise do perfil funcional e taxon?mico dos metagenomas estudados