Project description:This SuperSeries is composed of the following subset Series: GSE17834: Transcriptome analysis of Geobacter sulfurreducens grown with different nitrogen sources GSE17837: ChIP-chip of Geobacter sulfurreducens PCA with antibody against RpoN under various conditions. Refer to individual Series
Project description:We applied a ChIP-chip approach to elucidate the σN regulon experimentally under different growth conditions. This technique localizes DNA fragments within σN complexes enriched by chromatin immunoprecipitation using high-density oligonucleotide tilling arrays.
Project description:We applied a ChIP-chip approach to elucidate the σN regulon experimentally under different growth conditions. This technique localizes DNA fragments within σN complexes enriched by chromatin immunoprecipitation using high-density oligonucleotide tilling arrays. A nine ChIP-chip study using immunoprecipitated DNA (IP-DNA) from three separate culture conditions. The high-density oligonucleotide tiling arrays used were consisted of 381,174 oligonucleotide probes spaced 20 bp apart (30-bp overlap between two probes) across the G.sulfurreducens genome (NimbleGen). Experiments were conducted as three bioliogical replicates (different cultures)
Project description:BACKGROUND: The role of the RNA polymerase sigma factor RpoN in regulation of gene expression in Geobacter sulfurreducens was investigated to better understand transcriptional regulatory networks as part of an effort to develop regulatory modules for genome-scale in silico models, which can predict the physiological responses of Geobacter species during groundwater bioremediation or electricity production. RESULTS: An rpoN deletion mutant could not be obtained under all conditions tested. In order to investigate the regulon of the G. sulfurreducens RpoN, an RpoN over-expression strain was made in which an extra copy of the rpoN gene was under the control of a taclac promoter. Combining both the microarray transcriptome analysis and the computational prediction revealed that the G. sulfurreducens RpoN controls genes involved in a wide range of cellular functions. Most importantly, RpoN controls the expression of the dcuB gene encoding the fumarate/succinate exchanger, which is essential for cell growth with fumarate as the terminal electron acceptor in G. sulfurreducens. RpoN also controls genes, which encode enzymes for both pathways of ammonia assimilation that is predicted to be essential under all growth conditions in G. sulfurreducens. Other genes that were identified as part of the RpoN regulon using either the computational prediction or the microarray transcriptome analysis included genes involved in flagella biosynthesis, pili biosynthesis and genes involved in central metabolism enzymes and cytochromes involved in extracellular electron transfer to Fe(III), which are known to be important for growth in subsurface environment or electricity production in microbial fuel cells. The consensus sequence for the predicted RpoN-regulated promoter elements is TTGGCACGGTTTTTGCT. CONCLUSION: The G. sulfurreducens RpoN is an essential sigma factor and a global regulator involved in a complex transcriptional network controlling a variety of cellular processes.
Project description:We applied a ChIP-chip approach to elucidate the binding profiles of sigma factors (RpH, RpoN and RpoS) experimentally under different growth conditions. This technique localizes DNA fragments within DNA-protein complexes enriched by chromatin immunoprecipitation using high-density oligonucleotide tilling arrays.
Project description:We applied a ChIP-chip approach to elucidate the binding profiles of sigma factors (RpH, RpoN and RpoS) experimentally under different growth conditions. This technique localizes DNA fragments within DNA-protein complexes enriched by chromatin immunoprecipitation using high-density oligonucleotide tilling arrays. A 10 ChIP-chip study using immunoprecipitated DNA (IP-DNA) from three culture condtions against three alternative sigma factors . The high-density oligonucleotide tiling arrays used were consisted of 381,174 oligonucleotide probes spaced 20 bp apart (30-bp overlap between two probes) across the G.sulfurreducens genome (NimbleGen). Experiments were conducted as three bioliogical replicates (different cultures).
Project description:We applied a ChIP-chip approach to elucidate the binding profiles of RNAP and RpoD experimentally under different growth conditions. This technique localizes DNA fragments within DNA-protein complexes enriched by chromatin immunoprecipitation using high-density oligonucleotide tilling arrays.