Figure 4

Functions controlled by CtrA among alpha-proteobacteria. Enrichment of genes controlled by CtrA in COG categories (see also Additional file 8, Table S5). The scale corresponds to the p-value of the functional enrichment calculated as described in the Material and Methods. The p-value is inversely correlated to the strength of the functional enrichment of each regulon, i.e. a lower p-value indicates stronger enrichment.