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Transcription profiling of Listeria monocytogenes relA and codY mutants

ABSTRACT: Data is also available from http://bugs.sgul.ac.uk/E-BUGS-46

INSTRUMENT(S): NanoDrop

ORGANISM(S): Listeria monocytogenes

SUBMITTER:

PROVIDER: E-BUGS-46 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Characterization of relA and codY mutants of Listeria monocytogenes: identification of the CodY regulon and its role in virulence.

Bennett Hayley J HJ Pearce David M DM Glenn Sarah S Taylor Clare M CM Kuhn Michael M Sonenshein Abraham L AL Andrew Peter W PW Roberts Ian S IS

Molecular microbiology 20070301 5

Listeria monocytogenes is a Gram-positive intracellular parasite and the causative organism of human listeriosis. In this article we demonstrate that L. monocytogenes encodes a functional member of the CodY family of global regulatory proteins that is responsive to both GTP and branched chain amino acids. By transcript analyses we identified the CodY regulon in L. monocytogenes and demonstrated that it comprises genes involved in amino acid metabolism, nitrogen assimilation as well as genes invo ...[more]

PMID: 17302820

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2011-04-15 | E-BUGS-87 | biostudies-arrayexpress

Transcriptional profiling of Neisseria meningitidis Interacting with Human Epithelial Cells in a Long-Term In Vitro Colonization Model

Project description:Neisseria meningitidis is a commensal of humans that can colonize the nasopharyngeal epithelium for weeks to months and occasionally invades to cause life-threatening septicemia and meningitis. Comparatively little is known about meningococcal gene expression during colonization beyond those first few hours. In this study, the transcriptome of adherent serogroup B N. meningitidis strain MC58 was determined at intervals during prolonged cocultivation with confluent monolayers of the human respiratory epithelial cell line 16HBE14. At different time points up to 21 days, 7 to 14% of the meningococcal genome was found to be differentially regulated. The transcriptome of adherent meningococci obtained after 4 h of coculture was markedly different from that obtained after prolonged cocultivation (24 h, 96 h, and 21 days). Genes persistently upregulated during prolonged cocultivation included three genes (hfq, misR/phoP, and lrp) encoding global regulatory proteins. Many genes encoding known adhesins involved in epithelial adherence were upregulated, including those of a novel locus (spanning NMB0342 to NMB0348 [NMB0342-NMB0348]) encoding epithelial cell-adhesive function. Sixteen genes (including porA, porB, rmpM, and fbpA) encoding proteins previously identified by their immunoreactivity to sera from individuals colonized long term with serogroup B meningococci were also upregulated during prolonged cocultivation, indicating that our system models growth conditions in vivo during the commensal state. Surface-expressed proteins downregulated in the nasopharynx (and thus less subject to selection pressure) but upregulated in the bloodstream (and thus vulnerable to antibody-mediated bactericidal activity) should be interesting candidate vaccine antigens, and in this study, three new proteins fulfilling these criteria have been identified: NMB0497, NMB0866, and NMB1882. [Data is also available from http://bugs.sgul.ac.uk/E-BUGS-141]

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Transcription profiling by array of Dominant Role of Nucleotide Substitution in the Diversification of Serotype 3 Pneumococci over Decades and during a Single Infection

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2013-11-02 | E-BUGS-144 | biostudies-arrayexpress

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2012-10-14 | E-BUGS-136 | biostudies-arrayexpress

Transcription profiling of Yersinia pseudotuberculosis to determine the importance of the Rcs phosphorelay in its survival and pathogenesis

Project description:Data is also available from http://bugs.sgul.ac.uk/E-BUGS-57

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Transcription profiling of Yersinia pseudotuberculosis vagH mutants

Project description:Data is also available from http://bugs.sgul.ac.uk/E-BUGS-48

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2013-11-02 | E-BUGS-138 | biostudies-arrayexpress

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2007-03-07 | E-BUGS-2 | biostudies-arrayexpress

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