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A thermostable K + ‐stimulated vacuolar‐type pyrophosphatase from the hyperthermophilic bacterium Thermotoga maritima
Author(s) -
Pérez-Castiñeira José R.,
López-Marqués Rosa L.,
Losada Manuel,
Serrano Aurelio
Publication year - 2001
Publication title -
febs letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.593
H-Index - 257
eISSN - 1873-3468
pISSN - 0014-5793
DOI - 10.1016/s0014-5793(01)02390-0
Subject(s) - thermotoga maritima , pyrophosphatases , inorganic pyrophosphatase , thermophile , heterologous expression , biochemistry , thermostability , bacteria , archaea , biology , pyrophosphatase , saccharomyces cerevisiae , pyrophosphate , yeast , enzyme , gene , genetics , escherichia coli , recombinant dna
Current evidence suggests the occurrence of two classes of vacuolar‐type H + ‐translocating inorganic pyrophosphatases (V‐PPases): K + ‐insensitive proteins, identified in eukaryotes, bacteria and archaea, and K + ‐stimulated V‐PPases, identified to date only in eukaryotes. Here, we describe the functional characterization of a thermostable V‐PPase from the anaerobic hyperthermophilic bacterium Thermotoga maritima by heterologous expression in Saccharomyces cerevisiae . The activity of this 71‐kDa membrane‐embedded polypeptide has a near obligate requirement for K + , like the plant V‐PPase, and its thermostability depends on the binding of Mg 2+ . Phylogenetic analysis of protein sequences consistently assigned the T. maritima V‐PPase to the K + ‐sensitive class of V‐PPases so far only known for eukaryotes. The finding of a K + ‐stimulated V‐PPase also in a member of a primitive eubacterial lineage strongly supports an ancient evolutionary origin of this group of pyrophosphate‐energized proton pumps.