Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

DNA microarray analysis of genes positively regulated by TfoX

ABSTRACT: Vibrio cholerae strains A1552tfoX/pBAD and A1552tfoX/pBAD-tfoX were diluted 1:100 from over night cultures and grown in LB liquid medium containing 0.2 % L-arabinose and 100 Î¼g/ml ampicillin. At OD600=0.3, samples were quickly harvested in a microcentrifuge at room temperature and the bacterial pellet resuspended in Trizol reagent (GIBCO/BRL) and kept at -80 degrees C. The aqueous phase containing the RNA was isolated according to the manufacturer's manual and to which was added an equal volume of 70% ethanol. Using an RNeasy. column (Qiagen, Valencia, CA) the RNA was isolated and treated with DNase I solution. Labeling of cDNA was done as described by M. I. Voskuil et al., J. Exp. Med. 198, 705-13 (2003). Samples from A1552tfoX/pBAD were labeled with Cy3 and samples from A1552tfoX/pBAD-tfoX were labeled with Cy5. Duplicate samples from two individual experiments were hybridized to an oligonucleotide DNA microarray slide containing at least one oligonucleotide corresponding to every identified open-reading-frame of V. cholerae O1 El Tor strain N16961. Microarray slides were prehybridized (5 x SSC, 1% BSA, 0.1% SDS) for at least one hour at 42 degrees C and hybridization was performed in 2 x SSC, 0.1% SDS, 20% formamide at 54 degrees C over night. Set of arrays organized by shared biological context, such as organism, tumors types, processes, etc. Computed

ORGANISM(S): Vibrio cholerae

SUBMITTER: Melanie Blokesch

PROVIDER: E-GEOD-3577 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Publications

Chitin induces natural competence in Vibrio cholerae.

Meibom Karin L KL Blokesch Melanie M Dolganov Nadia A NA Wu Cheng-Yen CY Schoolnik Gary K GK

Science (New York, N.Y.) 20051201 5755

The mosaic-structured Vibrio cholerae genome points to the importance of horizontal gene transfer (HGT) in the evolution of this human pathogen. We showed that V. cholerae can acquire new genetic material by natural transformation during growth on chitin, a biopolymer that is abundant in aquatic habitats (e.g., from crustacean exoskeletons), where it lives as an autochthonous microbe. Transformation competence was found to require a type IV pilus assembly complex, a putative DNA binding protein, ...[more]

PMID: 16357262

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Dataset Information

DNA microarray analysis of genes positively regulated by TfoX

Publications

Chitin induces natural competence in Vibrio cholerae.

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