Reserva nitrogenada no genero Beijerinckia isolada da rizosfera de cana-de-açúcar. / Nitrogen reserve in the genus Beijerinckia isolated from sugarcane rhizosphere.
AUTOR(ES)
Tania Regina dos Santos
FONTE
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia
DATA DE PUBLICAÇÃO
30/08/2011
RESUMO
Beijerinckia sp. bacteria free-living nitrogen-fixing, commonly found in tropical lateritic soils. The cyanophycin produced by cyanobacteria is the only intracellular nitrogen reserve described to date. This study aimed to verify the intracellular buildup of nitrogen associated with Biological Nitrogen Fixation in five Beijerinckia isolated from the rhizosphere of sugarcane (Saccharum sp.). The results showed an increase in total cellular protein concentration concomitantly nitrogenase activity during the stationary phase of all isolates. The nitrogen fixation during this phase suggests that the fate of fixed nitrogen would be the storage granules. Chemical analysis of the reserve confirmed the presence of very high content of arginine in relation to other amino acids suggesting a different reserve of cyanophycin. In recombinant Escherichia coli confirmed a possible gene involved in nitrogen storage material in Beijerinckia sp.
ASSUNTO(S)
amino acids aminoácidos bacterial genetics bactérias fixadoras de nitrogênio cana-de-açúcar fixação de nitrogênio genética bacteriana nitrogen fixation nitrogen-fixing bacteria rhizosphere rizosfera sugar cane
