Phylogenetic analysis of ArcB proteins encoded in the arc gene cluster in L. hongkongensis. The tree was constructed by neighbor joining method using Kimura's correction and bootstrap values calculated from 1000 trees. Three hundred and thirty-four and 335 amino acid positions in ArcB1 and ArcB2, respectively, were included in the analysis. 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.