Unknown,Transcriptomics,Genomics,Proteomics

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SRNAs in Rhizobium etli differentially expressed during free-living and host-associated growth

ABSTRACT: 89 small non-coding RNAs (ncRNAs) were identified in the soil-dwelling alpha-proteobacterium Rhizobium etli by comparing an extensive compilation of ncRNA predictions to intergenic expression data of a whole-genome tiling array. The differential expression levels of some of these ncRNAs during free-living growth and during interaction with the eukaryotic host plant may indicate a role in adaptation to changing environmental conditions. In order to study expression in the free-living state, wild-type R. etli CFN42 was grown at 30ËC in acid minimal salts medium supplied with 10 mM NH4Cl and 10 mM succinate while monitoring the optical density (OD) of the culture. Samples were taken at OD600 = 0.3, 0.7 and 6 hours after reaching the maximum OD, representing early/late exponential and stationary phase, respectively. In order to study gene expression during host-associated growth, common bean plants (Phaseolus vulgaris cv. Limburgse vroege) were cultivated and inoculated as described previously. Nodules were harvested 2 and 3 weeks after inoculation and the bacteroids were purified by differential centrifugation.

ORGANISM(S): Rhizobium etli CFN 42

SUBMITTER: Lore Cloots

PROVIDER: E-GEOD-18580 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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SRNAs in Rhizobium etli differentially expressed during free-living and host-associated growth

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