FIG. 2.

Phylogenetic relationships, based on maximum-likelihood analyses of 16S rRNA sequences, of the thiotrophic and methanotrophic endosymbionts of Bathymodiolus sp. (boldface type) in the γ-Proteobacteria (1,266 sites analyzed; L = −8,744). Two α-proteobacterial species were used as an outgroup (only A. tumefaciens is shown). Bootstrap percentages were obtained by using 1,000 maximum-likelihood replicates, and values greater than 60% are indicated at the nodes. Scale bar = 10% estimated base substitutions.