Multiple alignment of 145 full-length bcr1 elements (≥120 bp) from B. anthracis Ames, B. cereus ATCC 10987, and B. cereus ATCC 14579. Sequences were aligned by using CLUSTALW (35) followed by manual editing with SEAVIEW (11). Consensus sequences computed with thresholds of 51, 60, 70, 80, and 90% conservation are included at the bottom of the alignment. When a threshold T is used, a residue appears in the consensus if it is present in ≥T% of the 145 bcr1 elements; otherwise, the character N is assigned. Furthermore, a plot of the conservation of each site was generated by CLUSTALX (36) and is shown below the alignment. The asterisk above the alignment indicates the single site where all 145 sequences have an identical nucleotide. Sequence lengths are given to the left of the alignment. Indels are represented by dashes. Bc denotes B. cereus.