Figure 2.

Neighbor-joining tree of Prochlorococcus PhnD proteins. Evolutionary distances for PhnD proteins were determined from the alignment of 320 aa positions using a neighbor-joining analysis. Neighbor-joining and maximum parsimony analyses were conducted using PAUP. Bootstrap resampling (1000) of neighbor-joining and maximum parsimony trees were performed in all analyses to provide confidence estimates for the inferred topologies. Bootstrap values (neighbor-joining/maximum parsimony) greater than 50% are indicated above the branches. Prochlorococcus PhnD proteins are shown in green. HL – high-light adapted strains, LL – low-light adapted strains. Different phn operon organizations in Prochlorococcus MIT9301 and MIT9303 and in different reference genomes are shown on the right; gray ORF represents genes not related to the phn operon.