Table 2. Comparison of B.subtilis 91 σ^A-regulated promoters and E.coli 132 σ⁷⁰-regulated promoters [(data adopted from Bateman et al. (12)].

Category	B.subtilis (%)	E.coli (%)
Total number of repressible promoters	61	69
Total number of activatable promoters	43	49
Promoters with repressor and activator sites	14	17
Promoters regulated by two or more different activators	6	7
Promoters regulated by two or more different repressors	5	3
Promoters with repeated homologous activator sites	3	13
Promoters with repeated homologous repressor sites	9	36