title: Pyruvate-phosphate dikinase of oxymonads and parabasalia and the evolution of pyrophosphate-dependent glycolysis in anaerobic eukaryotes.
abstract: In pyrophosphate-dependent glycolysis, the ATP/ADP-dependent enzymes phosphofructokinase (PFK) and pyruvate kinase are replaced by the pyrophosphate-dependent PFK and pyruvate phosphate dikinase (PPDK), respectively. This variant of glycolysis is widespread among bacteria, but it also occurs in a few parasitic anaerobic eukaryotes such as Giardia and Entamoeba spp. We sequenced two genes for PPDK from the amitochondriate oxymonad Streblomastix strix and found evidence for PPDK in Trichomonas vaginalis and other parabasalia, where this enzyme was thought to be absent. The Streblomastix and Giardia genes may be related to one another, but those of Entamoeba and perhaps Trichomonas are distinct and more closely related to bacterial homologues. These findings suggest that pyrophosphate-dependent glycolysis is more widespread in eukaryotes than previously thought, enzymes from the pathway coexists with ATP-dependent more often than previously thought and may be spread by lateral transfer of genes for pyrophosphate-dependent enzymes from bacteria.
authors.affiliation: Canadian Institute for Advanced Research, Botany Department, University of British Columbia, 3529-6270 University Boulevard, Vancouver, British Columbia V6T 1Z4, Canada.
authors.forename: Claudio H
authors.initials: CH
authors.lastname: Slamovits
authors.forename: Patrick J
authors.initials: PJ
authors.lastname: Keeling
mesh_terms: D000595:Amino Acid Sequence; D000693:Anaerobiosis; D000818:Animals; D020134:Catalytic Domain; D017124:Conserved Sequence; D011756:Diphosphates / Q000378:metabolism*; D056890:Eukaryota / Q000166:cytology / Q000201:enzymology / Q000378:metabolism*; D005057:Eukaryotic Cells / Q000166:cytology / Q000201:enzymology / Q000378:metabolism*; D019143:Evolution, Molecular; D006019:Glycolysis; D008969:Molecular Sequence Data; D010802:Phylogeny; D011772:Pyruvate, Orthophosphate Dikinase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid
chemical_list: D011756:Diphosphates; D011772:Pyruvate, Orthophosphate Dikinase