Phylogenetic analysis of ttrB encoded protein in tetrathionate reductase gene cluster in L. hongkongensis HLHK9. Phylogenetic tree showing the relationship of ttrB encoded proteins of L. hongkongensis HLHK9 to other species with complete ttr gene cluster constructed by neighbor-joining method. Bootstrap values were calculated from 1000 trees. The scale bar indicates the estimated number of substitutions per 20 amino acids. All names and accession numbers are given as cited in the GenBank database.