Archaebacterial ATPase: studies on subunit composition and quaternary structure of the F1-analogous ATPase from Sulfolobus acidocaldarius.
A modified procedure for the purification of soluble ATPase from the thermoacidophilic archaebacterium Sulfolobus acidocaldarius is described. In addition to (alpha) 65 and (beta) 51 kDa polypeptides, further subunits gamma * (20 kDa) and delta * (12 kDa) are demonstrated to be components of the enzyme, exhibiting a total molecular mass of 380 kDa. Molecular electron microscopic images of the native enzyme indicate a quaternary structure probably formed by the gamma *, delta *-complex as a central mass surrounded by a pseudohexagon of the peripherally arranged larger alpha and beta subunits. As can be derived from both molecular mass and electron microscopy data, the archaebacterial Sulfolobus-ATPase emerges to exist as an alpha 3 beta 3-quaternary structure with respect to the larger subunits. This is normally found in typical F1-ATPases of eubacterial and eukaryotic organisms. Therefore it is postulated that F1- and F0F1-ATPases, respectively, can occur ubiquitously in all urkingdoms of organisms as functional units of energy-transducing membranes.
Lübben
M
M
Institut für Biochemie, Medizinische Universität zu Lübeck.
Lünsdorf
H
H
Schäfer
G
G
D000251:Adenosine Triphosphatases / Q000302:isolation & purification; D001105:Archaea / Q000201:enzymology*; D001419:Bacteria / Q000201:enzymology*; D002499:Centrifugation, Density Gradient; D002850:Chromatography, Gel; D002852:Chromatography, Ion Exchange; D004591:Electrophoresis, Polyacrylamide Gel; D046911:Macromolecular Substances; D008854:Microscopy, Electron; D008970:Molecular Weight; D006180:Proton-Translocating ATPases; D013045:Species Specificity
D046911:Macromolecular Substances; D000251:Adenosine Triphosphatases; D006180:Proton-Translocating ATPases