Chromosome-wide distribution of CbpA in starved <i>E. coli</i>.

<p>(A) Distribution of CbpA across the <i>E. coli</i> chromosome. i) Genome-wide view of CbpA binding in starved MC108 cells. The figure shows ChIP-chip data for CbpA binding plotted against features of the <i>E. coli</i> genome in the form of a genome atlas. The data have been averaged across a 100,000 base pair window. The four chromosomal macrodomains (MD) are labelled ii) CbpA ChIP-chip data for a small section of the <i>E. coli</i> chromosome. The data have been averaged across a 10,000 base pair window. (B) Relationship between CbpA binding and DNA GC content. The graph shows the average CbpA binding signal plotted against the GC content of probes on the DNA microarray. The average GC content of the <i>E. coli</i> K-12 chromosome is shown by a dashed line. Very GC rich and GC poor probes were excluded during microarray design and are thus absent. (C) Effect of CbpA on DNA supercoiling <i>in vivo</i>. Panel i) shows an image of a 1% (v/v) agarose gel containing 2.5 µg/ml chloroquine. Plasmids were isolated from different genetic backgrounds and different stages of growth as indicated. Panel ii) also shows an image of a 1% (v/v) agarose gel containing 2.5 µg/ml chloroquine. Plasmids were isolated from rapidly dividing cells.