Metabolomics,Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

Transcriptional profiling of 2 outbreak strains of E. coli O157:H7 following exposure to epithelial cells

ABSTRACT: Two outbreak strains of E. coli O157:H7 differ phylogenetically, in gene content, and in epidemiological characteristics. The working hypothesis in this experiment was that these strains will also differ in the transcription of shared virulence genes. Indeed, following a 30 minute exposure to epithelial cells, strain TW14359 overexpressed major and ancillary virulence genes, relative to strain Sakai. E. coli O157:H7 strains were physiologically normalized by growth to stationary phase, twice, in MOPS minimal media. Cultures were then transferred to DMEM media for adaptation. After 3 h of growth in DMEM, O157:H7 cultures were used to infect monolayers of MAC-T epithelial cells. 30 min following incubation, aliquots of suspended, non-adherent bacteria were used for RNA extraction. Five biological replications of the experiment were performed with each strain and, together with dye-swaps, 10 array hybridizations were carried out. Array data were fitted to a mixed model ANOVA using the following linear model: array+dye+sample (biological replicate)+strain+error.

ORGANISM(S): Escherichia coli

SUBMITTER: Galeb Abu-Ali

PROVIDER: E-GEOD-17389 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Publications

Differences in adherence and virulence gene expression between two outbreak strains of enterohaemorrhagic Escherichia coli O157 : H7.

Abu-Ali Galeb S GS Ouellette Lindsey M LM Henderson Scott T ST Whittam Thomas S TS Manning Shannon D SD

Microbiology (Reading, England) 20091105 Pt 2

The Escherichia coli O157 : H7 TW14359 strain was implicated in a multi-state outbreak in North America in 2006, which resulted in high rates of severe disease. Similarly, the O157 : H7 RIMD0509952 (Sakai) strain caused the largest O157 : H7 outbreak to date. Both strains were shown to represent divergent phylogenetic lineages. Here we compared global gene expression patterns before and after epithelial cell exposure, as well as the ability to adhere to and invade epithelial cells, between the t ...[more]

PMID: 19892762

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Dataset Information

Transcriptional profiling of 2 outbreak strains of E. coli O157:H7 following exposure to epithelial cells

Publications

Differences in adherence and virulence gene expression between two outbreak strains of enterohaemorrhagic Escherichia coli O157 : H7.

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