Neighbor-joining phylogeny constructed from concatenated MLST gene fragment sequences. Sequences were obtained from the clinical human isolate and other strains representing the four subspecies of F. tularensis. The tree, which was created using MEGA2 software , is midpoint rooted. Bootstrap values ≥ 60 are presented and are based upon 1,000 replicates. The human clinical isolate clusters with the F. tularensis subsp. novicida clade, which is indicated with the right vertical bar. Sequences with an asterisk (*) were generated as part of this study. All other sequences were obtained from GenBank and originated from a study by Svensson et al. . The scale bar, expressing mean character difference, corresponds to 0.002 substitutions per nucleotide position.