Data/hora: 23/09/2024 12:09:23

Biblioteca(s): 	Embrapa Agrobiologia.	
Data corrente: 	10/06/1999	
Data da última atualização: 	10/06/1999	
Autoria: 	PEDROSA, F. O.; TEIXEIRA, K. R. dos S.; MACHADO, I. M. P.; STEFFENS, M. B. R.; KLASSEN, G.; BENELLI, E. M.; MACHADO, H. B.; FUNAYAMA, S.; RIGO, L. U.; ISHIDA, M. L.; YATES, M. G.; SOUZA, E. M.	
Título: 	Structural organization and regulation of the Nif genes of Herbaspirillum seropedicae.	
Ano de publicação: 	1997	
Fonte/Imprenta: 	Soil Biology and Biochemistry, Oxford, v. 29, n. 5/6, p. 843-846, 1997.	
Idioma: 	Inglês	
Conteúdo: 	The promoter regions of nifA and nifH genes of Herbaspirillum seropedicae have been isolated and investigated, and the nifA promoter has been characterized in detail. Both regions contain a -24/-12 type promoter and nifA-binding sites; the nifA promoter also has an NtrC-binding site. The nifA expression is activated by NtrC and repressed by ammonium ions but not by oxygen. When the NtrC-binding site was deleted nifA expression was NifA-dependent. The native NifA protein of H. seropedicae was unable to activate nifH expression in Escherichia coli whereas a truncated protein, lacking the N-terminal domain was able to activate nifH expression in the absence of oxygen and presence of iron, indicating that the N-terminal domain regulates NifA activity. The truncated protein also activates nifH in Azospirillum brasilense in the presence or absence of ammonium ions. This suggests that the N-terminal domain senses the nitrogen status of the cell. 	
Palavras-Chave: 	BNF; FBN; Fixação biologica de nitrogênio; Nitrogen fixing bacteria.	
Thesagro: 	Gene; Proteína.	
Thesaurus Nal: 	genes; proteins.	
Categoria do assunto: 	--	
Registro original: 	Embrapa Agrobiologia (CNPAB)	
Exemplares: 	CNPAB - (24464-1) - UPC - AP - -- -  -  - 22303 - DIS