Correlation of genome size with the number of PA and ECF sigma factors in Bacillaceae. The number of PA (black circles) and ECF (open circles) sigma factors genes identified in the genomes listed in Table 1 are plotted against genome size. The highlighted grey area is the observed number of PA and ECF sigma factor genes found for members of the Bc species-group. These results show that the number of ECF, but not PA, sigma factor genes is correlated with genome size.
Schmidt et al. BMC Genomics 2011 12:430 doi:10.1186/1471-2164-12-430