ChIP-chip of Geobacter sulfurreducens PCA with antibody against various sigma factors under various conditions

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).