Made available in DSpace on 2014-12-17T14:10:15Z (GMT). No. of bitstreams: 1 CiaxaresMC.pdf: 595430 bytes, checksum: 97825450a670945169f3df28f7765add (MD5) Previous issue date: 2008-03-14 / The human activities responsible for the ambient degradation in the modern world are diverse. The industrial activities are preponderant in the question of the impact consequences for brazilian ecosystems. Amongst the human activities, the petroliferous industry in operation in Potiguar Petroliferous Basin (PPB) displays the constant risk of ambient impacts in the integrant cities, not only for the human populations and the environment, but also it reaches the native microorganisms of Caatinga ground and in the mangrove sediment. Not hindering, the elaboration of strategies of bioremediation for impacted areas pass through the knowledge of microbiota and its relations with the environment. Moreover, in the microorganism groups associated to oil, are emphasized the sulfate-reducing prokaryotes (SRP) that, in its anaerobic metabolism, these organisms participate of the sulfate reduction, discharging H2S, causing ambient risks and causing the corrosion of surfaces, as pipelines and tanks, resulting in damages for the industry. Some ancestries of PRS integrate the Archaea domain, group of microorganisms whose sequenced genomes present predominance of extremophilic adaptations, including surrounding with oil presence. This work has two correlated objectives: i) the detection and monitoring of the gene dsrB, gift in sulfate-reducing prokaryotes, through DGGE analysis in samples of mDNA of a mangrove sediment and semiarid soil, both in the BPP; ii) to relate genomic characteristics to the ecological aspects of Archaea through in silico studies, standing out the importance to the oil and gas industry. The results of the first work suggest that the petrodegraders communities of SRP persist after the contamination with oil in mangrove sediment and in semiarid soil. Comparing the populations of both sites, it reveals that there are variations in the size and composition during one year of experiments. In the second work, functional and structural factors are the probable cause to the pressure in maintenance of the conservation of the sequences in the multiple copies of the 16S rDNA gene. Is verified also the discrepancy established between total content GC and content GC of the same gene. Such results relating ribosomal genes and the ambient factors are important for metagenomic evaluations using PCR-DGGE. The knowledge of microbiota associated to the oil can contribute for a better destination of resources by the petroliferous industry and the development of bioremediation strategies. Likewise, search to lead to the best agreement of the performance of native microbiota in biogeochemical cycles in Potiguar Petroliferous Basin ecosystem / S?o diversas as atividades humanas respons?veis pela degrada??o ambiental observada no mundo moderno. As atividades industriais s?o preponderantes na quest?o das conseq??ncias impactantes para os ecossistemas brasileiros. Entre as atividades antr?picas, a ind?stria petrol?fera atuante na Bacia Petrol?fera Potiguar (BPP), exp?e a risco constante de impactos ambientais nos munic?pios integrantes, n?o s? as popula??es humanas e o meio ambiente, mas tamb?m atinge os microrganismos nativos do solo da Caatinga e no sedimento do manguezal. N?o obstante, a elabora??o de estrat?gias de biorremedia??o de ?reas impactadas perpassa, dentre outros aspectos, pelo conhecimento da microbiota e suas rela??es com o meio. Entre os grupos de microrganismos associados ao petr?leo, destacam-se os procariotos redutores de sulfato (PRS) que, em seu metabolismo anaer?bico, participam da redu??o do sulfato, liberando g?s sulf?drico, causando riscos ambientais e ocasionando a corros?o de superf?cies, como tubula??es e tanques, resultando em preju?zos para a ind?stria. Algumas linhagens de PRS integram o dom?nio Archaea, grupo de microrganismos cujos genomas seq?enciados apresentam predomin?ncia de adapta??es extremof?licas, incluindo ambientes com presen?a de petr?leo. Este trabalho tem dois objetivos correlacionados: i) detectar e monitorar o gene dsrB, presente em procariotos redutores de sulfato, por perfis de DGGE gerados a partir de amostras ambientais de mDNA do manguezal de Diogo Lopes, e do solo do semi-?rido da regi?o da BPP; ii) relacionar caracter?sticas gen?micas aos aspectos ecol?gicos de Archaea, ressaltando sua import?ncia para a ind?stria do petr?leo, atrav?s de estudos in silico. Os resultados do primeiro trabalho sugerem que as comunidades petrodegradadoras de PRS persistem ap?s a contamina??o por petr?leo em sedimento de manguezal e do solo do semi?rido. A compara??o entre as popula??es dos dois locais de amostragem revela que as mesmas apresentam varia??es em seu tamanho e composi??o ao longo de um ano de experimento. No segundo trabalho especula-se que fatores funcionais e estruturais s?o a causa da press?o para a manuten??o da conserva??o das seq??ncias nas m?ltiplas c?pias do gene 16S rDNA. Verifica-se tamb?m a discrep?ncia observada entre o conte?do GC total e conte?do GC do mesmo gene. Tais resultados relacionando genes ribossomais a fatores ambientais s?o importantes para avalia??es metagen?micas empregando PCR-DGGE. O conhecimento da microbiota associada ao petr?leo pode contribuir para uma melhor destina??o de recursos por parte da ind?stria petrol?fera e o desenvolvimento de estrat?gias de biorremedia??o. Outrossim, busca contribuir para o melhor entendimento da atua??o da microbiota nativa nos ciclos biogeoqu?micos em ecossistemas da Bacia Petrol?fera Potiguar