Ssa amino acid variations and repeated regions. (A) Ssa3 changes in amino acids, including insertions and deletions were divided by the number of sequences for each amino acid position (# aa diffs). The length of Ssa3 (horizontal axis) displays Ssa3 amino acid positions (aa position) and includes all amino acid insertions (537 aa total), and the number of sequences available at each amino acid position on Ssa3 (# seqs) is given. The amplified Ssa3 repeat region location (aa 53-196, in relation to N. risticii Illinois) and variety are demonstrated below. Dark gray boxes indicate the 52-aa repeats found in the N. risticii sequences. Light gray boxes indicate the terminal 40-aa peptide found in all Neorickettsia sequences. Black lines indicate amino acid variations in relation to N. risticii Illinois. The box containing diagonal lines in SF indicates a 9-aa truncation in the 40-aa peptide in relation to the other Neorickettsia spp. (B) The dendrogram of a 241-aa fragment of Ssa1, including all insertions (five sequences total) is shown. *, bootstrap value of 90.0% or greater. GenBank accession numbers of new sequences are listed in Table 1.