Vacuolar-type ATPase in a hyperthermophilic archaeum, Thermococcus sp. KI.
Membrane ATPase was purified from a hyperthermophilic heterotrophic archaeum, Thermococcus sp. KI, which grew anaerobically at 90 degrees C in the presence of sulfur. The purified enzyme had an optimal temperature of 90 degrees C and its molecular mass was estimated to be 600 kDa. It consisted of 4 subunits with molecular masses of 70, 60, 29 and 15 kDa. While the ATPase activity was resistant to most ATPase inhibitors, the activity was reduced by nitrate, an inhibitor of the vacuolar (V)-type ATPase. N-terminal amino acid sequence of the 70 kDa subunit was similar to those of catalytic subunit of V-type ATPases. This indicates that hyperthermophilic heterotrophs have a V-type ATPase in their membranes.
Iida
T
T
Marine Biotechnology Institute, Shimizu Laboratories, Shizuoka, Japan. mbishim 1@super.win.or.jp
Hoaki
T
T
Kamino
K
K
Inatomi
K
K
Kamagata
Y
Y
Maruyama
T
T
D000251:Adenosine Triphosphatases / Q000037:antagonists & inhibitors / Q000302:isolation & purification / Q000378:metabolism*; D000595:Amino Acid Sequence; D001105:Archaea / Q000201:enzymology*; D002850:Chromatography, Gel; D002852:Chromatography, Ion Exchange; D004591:Electrophoresis, Polyacrylamide Gel; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006868:Hydrolysis; D008969:Molecular Sequence Data; D017386:Sequence Homology, Amino Acid; D014617:Vacuoles / Q000201:enzymology*
D004791:Enzyme Inhibitors; D000251:Adenosine Triphosphatases