Fig. 1.

Bayesian phylogenetic tree based on the translated amino acids of mannose-6-phosphate isomerase (MPI) with bootstrap values (when >50%) indicated at the nodes. All eukaryotic algal MPIs (including those of brown algae, diatoms, red algae, and green algae) originated from eukaryotic hosts. Brown algae MPIs underwent gene duplication in their common ancestor. Bacterial type II MPIs encode bifunctional enzymes with MPI and MPG activities. All MPI sequences were obtained from GenBank or OneKP databases (Table S1)