Figure 1.

Phylogenetic relationship of the proteobacteria. Unrooted dendrograms based on the 16S rRNA (A), rplT (ribosomal L20) (B), and intI (C) genes among the proteobacteria used in this study. The integrases from the three classes of MRIs are boxed in C. Organism abbreviations are as follows: Vch, Vibrio cholerae; Vme, V. metschnikovii; Vpa, V. parahaemolyticus; Vma, V. marinus; Vha, V. harveyi; Vho, V. hollisae; Vfi, V. fischeri; Lpe, Listonella pelagia; Pph, Photobacterium phosphoreum; Ppr, P. profundum; Eco, Escherichia coli; Ave, Aeromonas veronii; Son, Shewanella oneidensis; Spu, S. putrefaciens; Xca, Xanthomonas campestris; Xsp, Xanthomonas sp.; Neu, Nitrosomonas europaea. For the integrase and recombinase proteins: λ (of phage lambda), P2 (of phage P2), XerC/D (of E. coli). For intI nomenclature see Table 2.