Figure 4

CbbX phylogenetic tree. Bootstrap values higher than 50% are indicated at the nodes. The scale bar represents 0.4 mutations per site. Branch lengths are drawn to scale. Cyanobacterial CbbX sequences are boxed in green. CbbX sequences from red algae or secondary endosymbiotic events with red algae are boxed in red. CbbX sequences from all Stramenopiles (except Nannochloropsis) are boxed in brown. CbbX sequences encoded in the nucleus (nuc) or nucleomorph (nm) are boxed in orange. The Bacillus subtilis sporulation factor SpoVK is used as the outgroup.