Revealing archaeal diversity patterns and methane fluxes in Admiralty Bay, King George Island, and their association to Brazilian Antarctic Station activities

Brazilian research on extremophiles in the context of astrobiology

“…The interest in this group of micro-organism has recently increased with the detection of methane being produced on Mars (Mumma et al 2005), by some biotic or abiotic source. Previous results of a Brazilian project revealed that Antarctic archaeal community on sea sediments, dominated mainly by Crenarchaeota groups, may act as either a sink or source of methane to the atmosphere (Nakayama et al 2011). These authors also reported high archeal diversity in Antarctic shallow water using molecular approaches.…”

Impacto de hidrelétricas brasileiras nas mudanças climáticas: micro-organismos associados à emissão de metano em reservatórios.

“…During the incubation, methane production was quantified, and measurements were made in a gas chromatograph with flame ionization detection and methane concentrations were determined by direct comparison of data from a standard curve of methane 99.5%. The pattern area is determined by averaging the areas of 5 consecutive injections and the values are expressed in mmol of CH 4 (Nakayama et al, 2011). Aliquots of 1 ml each of triplicate microcosms were removed at the end of incubation time for DNA extraction.…”

“…Methane concentrations are determined from a calibration curve, prepared with 99.5% methane. The values are expressed in m moles of CH 4 (Nakayama et al, 2011). After time incubation will be done DNA extraction from samples using extraction kit: DNA Power Soil (MO BIO Laboratories, Solana Beach, USA).…”

Comunidades de arquéias metanogênicas em diferentes usos dos solos da Amazônia

“…As arquéias metanogênicas são microrganismos anaeróbios estritos que utilizam compostos simples de carbono resultantes da degradação anaeróbica da matéria orgânica, produzindo metano como um resíduo da respiração (NARIHIRO; SEKIGUCHI, 2011). Por metabolizarem uma gama restrita de compostos, esse processo é dependente de microrganismos sintróficos, que degradam compostos complexos em substratos simples de carbono, como o CO2, acetato e compostos que contem grupos metil, permitindo que sejam utilizados pelos microrganismos metanogênicos (NAKAYAMA et al, 2011).…”

“…As amostras de solo foram pesadas e 5 g foram adicionadas nos frascos contendo meio previamente autoclavado e reduzido pela adição de cisteína ( (NAKAYAMA et al, 2011). Com os resultados das concentrações, em mmol, de metano emitido foram construídos gráficos de emissão de metano dos cultivos enriquecidos.…”