title: Deep origin of plastid/parasite ATP/ADP translocases.
abstract: Membrane proteins that transport ATP and ADP have been identified in mitochondria, plastids, and obligate intracellular parasites. The mitochondrial ATP/ADP transporters are derived from a broad-specificity transport family of eukaryotic origin, whereas the origin of the plastid/parasite ATP/ADP translocase is more elusive. Here we present the sequences of five genes coding for ATP/ADP translocases from four species of Rickettsia. The results are consistent with an early duplication and divergence of the five ATP/ADP translocases within the rickettsial lineage. A comparison of the phylogenetic depths of the mitochondrial and the plastid/parasite ATP/ADP translocases indicates a deep origin for both transporters. The results provide no evidence for a recent acquisition of the ATP/ADP transporters in Rickettsia via horizontal gene transfer, as previously suggested. A possible function of the two types of ATP/ADP translocases was to allow switches between glycolysis and aerobic respiration in the early eukaryotic cell and its endosymbiont.
authors.affiliation: Department of Molecular Evolution, Evolutionary Biology Center, Uppsala University, Uppsala, Sweden.
authors.forename: Haleh
authors.initials: H
authors.lastname: Amiri
authors.forename: Olof
authors.initials: O
authors.lastname: Karlberg
authors.forename: Siv G E
authors.initials: SG
authors.lastname: Andersson
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics; D002693:Chlamydiaceae / Q000201:enzymology / Q000235:genetics; D005057:Eukaryotic Cells / Q000201:enzymology / Q000382:microbiology; D019143:Evolution, Molecular; D022761:Gene Transfer, Horizontal; D006790:Host-Parasite Interactions; D008928:Mitochondria / Q000201:enzymology / Q000235:genetics; D000226:Mitochondrial ADP, ATP Translocases / Q000235:genetics*; D008969:Molecular Sequence Data; D010802:Phylogeny; D018087:Plastids / Q000201:enzymology* / Q000235:genetics; D012281:Rickettsia / Q000201:enzymology* / Q000235:genetics; D012284:Rickettsia rickettsii / Q000201:enzymology / Q000235:genetics; D012286:Rickettsia typhi; D017421:Sequence Analysis; D017386:Sequence Homology, Amino Acid
chemical_list: D001426:Bacterial Proteins; D000226:Mitochondrial ADP, ATP Translocases