FnrL regulon in Rhodobacter sphaeroides

In this study, we performed a ChIP-chip experiment to determine the regulon of FnrL in Rhodobacter sphaeroides. We grew R. sphaeroides under anaerobic photosnthetic conditions, in which FnrL is expected to bind DNA and contol gene expression, and immuno-precipitated FnrL, but also sigma70 and the Beta' subunits of RNA polymerase to determine transcription activity. DNA immunoprecipitated with polyclonal antibodies against FnrL, sigma70, or the Beta' subunit of RNA polymerase was labelled with Cy5 and hybridized on two-color tilling arrays (triplicates for each) with genomic DNA as an input control labelled with Cy3.