Figure 2. . . . Phylogenetic tree showing 30 Bordatella holmesii isolates, B. pertussis 536, B. parapertussis 2591, B. bronchiseptica RB50, B. avium 197N, and B. hinzii BC304. Tree was constructed on the basis of concatenated nucleotide sequences of atpD, rpoB, tuf and rnpB genes. Bootstrap values >50% in 1,000 replicates are indicated. Scale bar indicates substitutions per site. CDC, Centers for Disease Control and Prevention; MDPH, Massachusetts Department of Public Health; –, unknown. Scale bar indicates nucleotide substitutions per site.