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Transcriptome comparison of wild type Azoarcus sp. strain BH72 grown under nitrogen fixation (experiment) with cells grown with combined nitrogen (ammonia) as nitrogen source

ABSTRACT: Model endophyte Azoarcus sp. BH72 is known to contribute fixed nitrogen to its host Kallar grass by nitrogen fixation and also expresses nitrogenase genes endophytically in rice seedlings in gnotobiotic culture. Availability of fixed nitrogen is one of the important signals regulating the transcription of nitrogenase genes and hence nitrogen fixing activity. Therefore, we analysed global transcription in response to differences in the nitrogen source. Transcription profiles of cells grown microaerobically (0.6% oxygen) on minimal medium with nitrogen (N2-fixing) versus ammonium (combined nitrogen) were compared using a genome-wide microarray approach and differences in the gene expression profile were monitored. RNA from cells grown on nitrogen-free synthetic medium under nitrogen fixation (experiment) and combined nitrogen source as ammonium chloride (control) was used for two-color whole-genome microarray approach.

ORGANISM(S): Azoarcus sp.

SUBMITTER: Barbara Reinhold-Hurek

PROVIDER: E-GEOD-49394 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Transcriptome comparison of the wild type strain Azoarcus sp. BH72 with that of nifLA knockout strain under nitrogen fixing condition

Project description:Azoarcus sp. BH72 is known to express nitrogenase genes endophytically in rice seedlings in gnotobiotic culture. Availability of fixed nitrogen is one of the important signals regulating the transcription of nitrogenase genes and hence nitrogen fixing activity. NifA is the essential transcription activator of nif genes. RNA isolated from the nifA knockout mutant of strain BH72 was compared with the transcriptome of wild type under nitrogen fixing condition using a global genome wide microarray approach and the differences in the gene expression profile were monitered. RNA isolated from wild type strain BH72 and nifLA mutant strain BHLAO grown respectively under microaerobic nitrogen fixing condition with glutamate as poor nitrogen source was used for two color whole genome microarray approach

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Project description:This SuperSeries is composed of the SubSeries listed below. Refer to individual Series

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