Fig. 6.

Percentage of promoters in indicated bacterial species containing a thymine at the last position of the −10 hexamer (−7) or an extended −10 consensus (TG) at −14, −15, or both. Percentages of promoters with identifiable −10 elements are shown on the y axis. Percentages of those promoters with −7T or extended −10 elements or both are indicated at the top of each bar and are relative to all promoters with identified −10 elements for that species. Promoters were identified based on published TSS data (cited in the main text) and sequence similarity to consensus E. coli −10 element as described in SI Appendix, Expanded Materials and Methods.