Fig. 2.

—Major events in the evolution of the pt genomes in eustigmatophytes. The scheme shows inferred events of gene loss and gain along the eustigmatophyte phylogeny. The pt genome of the chrysophyte Ochromonas sp. CCMP 1393 (a representative of the presumed sister lineage of eustigmatophytes) is included to provide a broader phylogenetic context. Genes lost are in red, genes gained are in blue (“ebo” refers to gain or loss of the whole operon). Losses mapped before divergence of Ochromonas sp. and eustigmatophytes may have happened at various deep branches of the ochrophyte phylogeny. Possible homology of orf1_gon and orf1_eust genes is discussed and detail concerning the split sufB gene (or pseudogene?) are provided in the main text. Note labels of some genes (e.g., acpP) at multiple branches in the tree, indicating multiple independent losses during the eustigmatophyte evolution. Taxa printed in bold are those for which the pt genome sequence is reported in this study.