A thermostable vacuolar-type membrane pyrophosphatase from the archaeon Pyrobaculum aerophilum: implications for the origins of pyrophosphate-energized pumps.
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.
Drozdowicz
Y M
YM
Plant Science Institute, Department of Biology, University of Pennsylvania, Philadelphia, PA 19104-6018, USA.
Lu
Y P
YP
Patel
V
V
Fitz-Gibbon
S
S
Miller
J H
JH
Rea
P A
PA
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*
D019843:Archaeal Proteins; D002412:Cations; D011756:Diphosphates; D004164:Diphosphonates; D017494:Proton Pumps; D004024:Dicyclohexylcarbodiimide; D011755:Pyrophosphatases; D043564:Inorganic Pyrophosphatase