Data/hora: 10/06/2024 18:58:36

Biblioteca(s): | Embrapa Agrobiologia.
Data corrente: | 06/08/2001
Data da última atualização: | 06/08/2001
Autoria: | MINERDI, D.; FANI, R.; GALLO, R.; BOARINO, A.; BONFANTE, P.
Título: | Nitrogen fixation genes in an endosymbiotic Burkholderia strain.
Ano de publicação: | 2001
Fonte/Imprenta: | Applied and Environmental Microbiology, Washington, v. 67, n. 2, p. 725-732, 2001.
Idioma: | Inglês
Conteúdo: | In this paper we repor the identification and characterization of a DNA region containing putative nif genes and belonging to a Burkholderia endosymbiont of the arbuscular mycorrhizal fungus Gigaspora margarita. A genomic library of total DNA extracted from the fungal spores was  also representative of the bacterial genome and was used to investigate the prokaryotic genome. Screening of the library with Azospirillum brasiliense nifHDK genes as the prokaryotic probes led to the identification of a 6,413-bp region. Analysis revealed three open reading frames encoding putative proteins with a very high degree of sequence similarity with the two subunits (NifD and NifK) of the component I and with component II (NifH) of nitrogenase from different diazotrophs. The three genes were arranged in an operon similar to that shown by most archaeal and bacterial diazothophs. PCR experiments with primers designed on the Burkholderia nifHDK genes and Southerm blot analysis demostrate that they actually belong to the genome of the G. margarita endosymbiont. They offer, therefore, the first sequence for the nif operon described for Burkholderia. Reverse transcriptase PCR experiments with primers designed on the Burkholderia nifH and nifH and nifD genes and performed on total RNA extracted from spores demostrate that the gene expression was limited to the germination phase. A phylogenetic analysis performed on the available nifK sequences placed the endosymbiotic Burkholderia close to A.brasilense.
Palavras-Chave: | BNF; Fixação biologica de nitrogênio; FNB; Nitrogen fixing bacteria.
Thesagro: | DNA; Micorriza Vesicular Arbuscular; Nitrogenase.
Thesaurus Nal: | vesicular arbuscular mycorrhizae.
Categoria do assunto: | --
Registro original: | Embrapa Agrobiologia (CNPAB)
Exemplares: | CNPAB - (24618-1) - ADD - SP - -- -  -  - 22427 - DIS