title: A thermostable vacuolar-type membrane pyrophosphatase from the archaeon Pyrobaculum aerophilum: implications for the origins of pyrophosphate-energized pumps.
abstract: Vacuolar-type H(+)-translocating pyrophosphatases (V-PPases) have been considered to be restricted to plants, a few species of phototrophic proteobacteria and protists. Here, we describe PVP, a thermostable, sequence-divergent V-PPase from the facultatively aerobic hyperthermophilic archaeon Pyrobaculum aerophilum. PVP shares only 38% sequence identity with both the prototypical V-PPase from Arabidopsis thaliana and the H(+)-PPi synthase from Rhodospirillum rubrum, yet possesses most of the structural features characteristic of V-PPases. Heterologous expression of PVP in Saccharomyces cerevisiae yields a M(r) 64¿ omitted¿000 membrane polypeptide that specifically catalyzes Mg(2+)-dependent PPi hydrolysis. The existence of PVP implies that PPi-energized H(+)-translocation is phylogenetically more deeply rooted than previously thought.
authors.affiliation: Plant Science Institute, Department of Biology, University of Pennsylvania, Philadelphia, PA 19104-6018, USA.
authors.forename: Y M
authors.initials: YM
authors.lastname: Drozdowicz
authors.forename: Y P
authors.initials: YP
authors.lastname: Lu
authors.forename: V
authors.initials: V
authors.lastname: Patel
authors.forename: S
authors.initials: S
authors.lastname: Fitz-Gibbon
authors.forename: J H
authors.initials: JH
authors.lastname: Miller
authors.forename: P A
authors.initials: PA
authors.lastname: Rea
mesh_terms: D000595:Amino Acid Sequence; D019843:Archaeal Proteins / Q000037:antagonists & inhibitors / Q000096:biosynthesis / Q000302:isolation & purification / Q000378:metabolism*; D002412:Cations / Q000378:metabolism; D004024:Dicyclohexylcarbodiimide / Q000494:pharmacology; D011756:Diphosphates / Q000378:metabolism*; D004164:Diphosphonates / Q000494:pharmacology; D006868:Hydrolysis; D043564:Inorganic Pyrophosphatase; D008969:Molecular Sequence Data; D017494:Proton Pumps / Q000378:metabolism*; D011755:Pyrophosphatases / Q000037:antagonists & inhibitors / Q000096:biosynthesis / Q000302:isolation & purification / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid; D019624:Thermoproteaceae / Q000201:enzymology*; D014617:Vacuoles / Q000201:enzymology*
chemical_list: D019843:Archaeal Proteins; D002412:Cations; D011756:Diphosphates; D004164:Diphosphonates; D017494:Proton Pumps; D004024:Dicyclohexylcarbodiimide; D011755:Pyrophosphatases; D043564:Inorganic Pyrophosphatase