Utiliza????o de nitrato por Telmatobacter sp. AB60 Acidobacteria

• Autor(a) principal: Moura, Kamila Suellen Paiva de
• Data de Publicação: 2020
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UCB
• Texto Completo: https://bdtd.ucb.br:8443/jspui/handle/tede/2701
• topic: Acidobacteria; Ciclo do nitrog??nio; Nitrogen cycle; Acidobacteria; CNPQ::CIENCIAS BIOLOGICAS

Acidobacteria physiology and their role in the biogeochemical cycles remain relatively unknown compared to another widespread phylum such as Proteobacteria. Although some studies have focused on carbon usage by Acidobacteria other aspects of their metabolism were neglected as their use of nitrogen or phosphorous. We have previously obtained a few isolates of Acidobacteriia from the Cerrado, which soils are acidic and poor in phosphorous and nitrate. The objective of this work was to investigate the nitrogen metabolism pathways present in the genome of the isolate Telmatobacter sp. AB60, an Acidobacteria from the Class Acidobacteriia. The genome of Telmatobacter sp. AB60 was previously sequenced revealing the presence of six genes involved in assimilatory nitrogen metabolism, such as nasAB e nirA (nitrate and nitrite reductase, respectively). Comparison of the deduced amino acid sequences of NasA and NirA revealed that the Acidobacteria genes more closely related to each other than to any other phylum. Nitrate and nitrite were used as sole nitrogen source separately and in combination, in oxic and anoxic conditions. The isolate AB60 grew on nitrate as sole nitrogen source and lactate as carbon and electron source. Growth was observed both in the presence and absence of oxygen. Assimilative nitrate reduction was observed for the first time in Acidobacteria, since isolate AB60 can use nitrate and lactate for growth and does not release of ammonia in the supernatant of the culture. On the other hand, the use of 2 mM of nitrite as sole nitrogen source inhibited the growth of isolate AB60.The next step of this work will be to test gene regulation in the presence of nitrate and nitrite, to detect other metabolic products during growth, an then broaden our knowledge of the Acidobacteriia??s role in the nitrogen cycle of the Cerrado.