Microarray transcription profiling of a Shewanella oneidensis etrA mutant.
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ABSTRACT:
SUBMITTER: Beliaev AS
PROVIDER: S-EPMC135233 | biostudies-literature | 2002 Aug
REPOSITORIES: biostudies-literature
Publications
Microarray transcription profiling of a Shewanella oneidensis etrA mutant.
Beliaev Alex S AS Thompson Dorothea K DK Fields Matthew W MW Wu Liyou L Lies Douglas P DP Nealson Kenneth H KH Zhou Jizhong J
Journal of bacteriology 20020801 16
DNA microarrays were used to examine the effect of an insertional mutation in the Shewanella oneidensis etrA (electron transport regulator) locus on gene expression under anaerobic conditions. The mRNA levels of 69 genes with documented functions in energy and carbon metabolism, regulation, transport, and other cellular processes displayed significant alterations in transcript abundance in an etrA-mutant genetic background. This is the first microarray study indicating a possible involvement of ...[more]
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Project description:Comparisson of expression profiling of a etrA deletion mutant strain (experimental sample) with that of the wild type Shewanella oneidensis MR-1 strain to assess global direct/indirect genetic regulation EtrA in Shewanella oneidensis MR-1 shares 73.6% and 50.8% amino acid sequence identity with the oxygen-sensing regulator Fnr in E. coli and Anr in Pseudomonas aeruginosa, respectively; however, its regulatory role of anaerobic metabolism in Shewanella spp. is complex and not well understood. Whole-genome expression profiling using a etrA gene deletion mutant as the experimental sample and the wild type strain as the reference, determine that EtrA fine-tunes the expression of genes involved in various anaerobic metabolic pathways, including nitrate, fumarate and dimethyl sulfoxide reduction. Moreover, genes involved in prophage activation and and genes implicated in aerobic metabolism were also differentially expressed. In contrast to previous studies that attributed a minor regulatory role to EtrA in Shewanella spp., this study demonstrates that EtrA acts as a global transcriptional regulator and cofers physiological advantages to the strain under certain growth conditions.
2011-01-29 | GSE26935 | GEO
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