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Ishida,M.L.; Assumpção,M.C.; Machado,H.B.; Benelli,E.M.; Souza,E.M.; Pedrosa,F.O.. |
Two Azospirillum brasilense open reading frames (ORFs) exhibited homology with the two-component NtrY/NtrX regulatory system from Azorhizobium caulinodans. These A. brasilense ORFs, located downstream to the nifR3ntrBC operon, were isolated, sequenced and characterized. The present study suggests that ORF1 and ORF2 correspond to the A. brasilense ntrY and ntrX genes, respectively. The amino acid sequences of A. brasilense NtrY and NtrX proteins showed high similarity to sensor/kinase and regulatory proteins, respectively. Analysis of lacZ transcriptional fusions by the ß-galactosidase assay in Escherichia coli ntrC mutants showed that the NtrY/NtrX proteins failed to activate transcription of the nifA promoter of A. brasilense. The ntrYX operon... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Azospirillum brasilense; Two-component regulatory system; Nitrogen regulation; NtrYX genes; NtrBC genes. |
Ano: 2002 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2002000600004 |
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