Sequence comparison of pPTs from higher plants, algae, and Apicomplexa. Sequences were obtained from NCBI, the Galdieria sulfuraria genome project website (http://genomics.msu.edu/galdieria/sequence_data.html), the Phaeodactylum tricornutum website (http://genome.jgi-psf.org/Phatr2/Phatr2.home.html), and the Toxoplasma gondii database ToxoDB. The TPT sequence from spinach (Spinacia oleracea) was aligned with the following sequences: the TPT from Brassica oleracea, the GPT from Arabidopsis thaliana, a pPT from Galdieria sulfuraria, two pPTs from Phaeodactylum tricornutum, two pPTs from Plasmodium falciparum, two pPTs from P. berghei, a pPT from P. chabaudii, pPTs from P. yoelii, a pPT from Toxoplasma gondii (TgPT), a pPT from Babesia bovis, a pPT from Theileria parva, and a pPT from T. annulata. The sequence comparison and prediction of transmembrane helices were done as described in Materials and Methods. The identities of amino acid residues to the Spinacia oleracea TPT sequence are indicated by dots. The locations of transmembrane helices are indicated by solid lines, while two potential substrate binding sites are marked by boxes.