Data/hora: 10/06/2024 09:05:01

Biblioteca(s): | Embrapa Agrobiologia.
Data corrente: | 05/07/2001
Data da última atualização: | 28/07/2008
Autoria: | ECKERT, B.; WEBER, O. B.; KIRCHHOF, G.; HALBRITTER, A.; STOFFELS, M.; HARTMANN, A.
Título: | Azospirillum doebereinerae sp. nov., a nitrogen-fixing bacterium associated with the C4-grass Miscanthus.
Ano de publicação: | 2001
Fonte/Imprenta: | International Journal of Systematic and Evolutionary Microbiology, Reading, v. 51, p. 17-26, 2001.
Idioma: | Inglês

Conteúdo:

A new group of nitrogen-fixing Azospirillum sp. bacteria was isolated from the roots of the C4-gramineous plant Miscanthus. Polyphasic taxonomy was performed, including auxanography using API galleries, physiological tests and 165 rRNA sequence comparison. The ability of the isolates to fix dinitrogen was evaluated by amplification of the nifD gene, immunodetection of the dinitrogenase reductase and acetylene-reduction assay. On the basis of these results, the nitrogen-fixing isolates represent a new species within the genus Azospirillum. Its closest phylogenetic neighbours, as deduced by 165 rDNA- based analysis, are Azospirillum lipoferum, Azospirillum largimobile and Azospirillum brasilense with 96.6,96.6 and 95.9% sequence similarity, respectively. Two 165 rRNA-targeting oligonucleotide probes were developed which differentiate the new species from the other Azospirillum species by whole-cell fluorescence hybridization. Strains of the new species are curved rods or S-shaped, 1.0-1.5 /lm in width and 2.0-30 /lm in length, Gram-negative and motile with a single polar flagellum. Optimum growth occurs at 30 °C and at pH values between 6.0 and 7.0. No growth takes place at 37 °C. They have a respiratory type of metabolism, grow well on arabinose, D-fructose, gluconate, glucose, glycerol, malate, mannitol and sorbitol. They differ from A. 
largimobile and A. lipoferum by their inability to use N-acetylglucosamine and D-ribose, from A. lipoferum by their ability to grow without biotin supplementation and from A. brasilense by their growth with D-mannitol and D-sorbitol as sole carbon sources. Nitrogen fixation occurs in microaerobic nitrogen-limited conditions. For this species, the name Azospirillum doebereinerae sp. nov. is suggested, with strain GSF71T as the type strain ( = DSM 13131T; reference strain Ma4 = DSM 13400). Its G+C content is 70.7 mol%.

Palavras-Chave: | Bactéria diazotrófica; Diazotrophic bacteria.
Thesaurus Nal: | Azospirillum.
Categoria do assunto: | --
Registro original: | Embrapa Agrobiologia (CNPAB)

Exemplares:

CNPAB - (2304-1) - UPC - SP - -- -  -  - 0022540 - DIS
CNPAB - (2304-2) - UPC - SP - -- -  -  - 0022540-1 - DIS