Estudos metagenômicos e computacionais da sulfetogênese: implicações para a atividade petrolífera na bacia potiguar

Abstract

The Potiguar Oil Basin (BPP) composes 119,300 Km2, comprising more than 3,500 producer wells, over 5,000 miles of pipeline and storage capacity around 211,500 m3. The sulfate reducing prokaryotes (SRP) are responsible for damage to the oil industry, as biodegradation of oil and bio-corrosion of metallic surfaces in industrial facilities through the production of H2S and in natural environments, contribute to the biogeochemical cycles, acting in microbial consortia, including the degradation of hydrocarbons. Mangrove areas studied in this paper refer to locations of BPP identified with coastal sensitivity index (ISL) grade 10. In mangrove sediment samples of Diogo Lopes, and Areia Branca (RN), Paracuru and Fortim (CE) and soils of Caatinga from Estrada do Óleo (RN), microbial communities were analyzed by native DNA metagenomic by PCR-DGGE using the dsrB gene as a molecular biomarker. This work highlights the occurrence of native communities of SRP in sediments of the BPP (RN/CE) with ability to respond to acute and/or chronic pollution by oil and oil products. The SRP communities exhibit changes in seasonality and in the composition of communities before the contamination. On the other hand, although the use of sulfetogenesis control strategies of SRP is accomplished with the use of enzyme inhibitors, the molecular events of the process are little known. With the aim of studying the inhibition of sulfetogenesis were obtained 3-D computer models of enzyme dissimilatory sulfite reductase from Desulfovibrio alaskensis, Desulfovibrio vulgaris Hildenborough and Archaeoglobus fulgidus and conducted computer simulations of docking with sulfite. The results of the simulations suggest a competition with nitrite and sulfite by the catalytic site, thus promoting the inhibition of dissimilatory sulfate reduction in SRP. Finally, data on the status quo of the native communities of SRP in the BPP are of interest to the oil industry and society. They can provide environmental actions that may include the use of inhibitors. These molecules, if tested in computational simulations as this work can contribute to the synthesis of new molecules or the improvement of inhibition of sulfetogenesis.