Figure 2

Phylogenies of two starch biosynthesis enzymes exhibiting compartmental specialization. A: Starch phosphorylase gene family (PHO); B: Phosphoglucomutase gene family (PGM). Paralogs are identified by species name. Phylogenies are rooted with Prochlorococcus marinus and Synechoccus sp. The scale is 0.1 substitutions per site. Nodes with bootstrap values lower than 90% were aggregated into rakes. Black circles indicate duplication events. Branches (a and b) emerging from duplications D1 were tested for deviation from neutral evolution. Corresponding outgroup sequences used to infer ancestral states are followed by duplication name (D1) in square brackets. Branches for which positive selection was detected are colored in red.