Phylogenetic distribution and genetic structure of Mistic. (a) Phylogenetic tree showing the relationship between the Bacillus species probed in this study (starred) or those with fully sequenced genomes. Those with the YugP (metalloprotease) and YugO-b (K+ channel) genes sequentially arranged in their chromosome are indicated in blue. Those with Mistic homologues are highlighted (grey). (b) Genetic structure of the region in B. subtilis analyzed by this study, with the sequenced region between YugP (purple) and YugO-b (magenta) highlighted (grey). (c) Sequence alignment of the genetic material between the YugP and YugO-b genes from five Bacillus species (A = green, C = teal, G = blue, T = lime) highlighting deletions and insertions (white). Translation initiation codons are marked with arrows, colored as in (b). B. pumilus has approximately 250 fewer bases between the two primary genes, consistent with the lack (or loss) of an 84 residue protein preceding the K+ channel open-reading-frame. The genomic region of B. subtilis that encodes the first 26 amino acids of its Mistic homologue (between the grey and black arrows), aligns with numerous frame-shifting mutations and stop codons (not shown) in even the most closely related species (B. mojavensis) suggestive that the internal methionine (residue 27) may also serve as an in vivo translation initiation start site for Mistic.