Reconstruction of phylogenetic relationships among members of the OM60/NOR5 clade based on protein-coding genes. Phylogenetic trees were reconstructed as outlined in the legend of Figure 1. Size bars represent an estimated sequence divergence of 10%. A. Dendrogram based on partial pufLM nucleotide sequences. The pufLM nucleotide sequence of Chloroflexus aurantiacus [GenBank:CP000909] was used as an outgroup (not shown). The red color indicates representatives of the OM60/NOR5 clade, a blue color betaproteobacteria, a green color alphaproteobacteria and sequences given in black are affiliated to the order Chromatiales. B. Dendrogram based on partial rpoB nucleotide sequences of members of the OM60/NOR5 clade. Strains known to produce BChl a are given in red, names in blue indicate the presence of proteorhodopsin encoding genes. The rpoB sequence of Pseudomomas aeruginosa PAO1 [GenBank:AE004091] was used as an outgroup.