The plasma membrane ATPase of the thermoacidophilic archaebacterium Sulfolobus acidocaldarius
- 1 September 1987
- journal article
- Published by Wiley in European Journal of Biochemistry
- Vol. 167 (2), 211-219
- https://doi.org/10.1111/j.1432-1033.1987.tb13325.x
Abstract
The plasma-membrane-associated ATPase of the thermoacidophilic archaebacterium Sulfolobus acidocaldarius characterized in a previous work [M. Lübben & G. Schäfer (1987) Eur. J. Biochem. 164, 533-540] has been solubilized. It can be easily removed from the membrane by mild treatment with zwitterionic detergents, therefore it appears to be a peripheral membrane protein analogous to the soluble F1-ATPase of eubacteria and eukaryotes. Further purification has been achieved by subsequent gel permeation and ion-exchange chromatography. The final purity is greater than 70% as judged by staining intensities after SDS/polyacrylamide gel electrophoresis. The ATPase consists of two major polypeptides of 65 kDa (alpha) and 51 kDa (beta) in comparable quantities; a minor band (20 kDa) is assumed to be a contaminant or a constitutive part of the enzyme, possibly copurified in substoichiometric amount. The native molecular mass of the solubilized ATPase determined by gel permeation is 430 kDa. Considering the precision of these methods, it remains open whether a 3:3 stoichiometry reflects the contribution of alpha and beta subunits to the quaternary structure, in analogy to known F1-ATPases. The catalytic properties resemble those of the membrane-bound state. There are two pH optima at 5.3 and 8.0 in the absence and only one optimum at 6.5 in the presence of the activating anion sulfite. Activity is strictly dependent on the divalent cations Mg2+ or Mn2+. ATP and dATP are hydrolyzed with highest rates; also other purine and pyrimidine nucleotides are cleaved significantly, but not ADP, pyrophosphate and p-nitrophenyl phosphate. The ATPase is insensitive to azide or vanadate but is inhibited by relatively low concentrations of nitrate. Polyclonal antisera have been raised against the beta subunit of the Sulfolobus ATPase. Cross-reactivities with cellular or membrane extracts of a number of archaebacteria, eubacteria and chloroplasts have been analyzed by means of Western blotting and immunodecoration. A strong cross-reactivity with other genera of the Sulfolobales is observed, also with Methanobacterium, Methanosarcina, Methanolobus and Halobacterium. Even membranes of the eubacterium Escherichia coli and of eukaryotic chloroplast react with the antibodies. With one exception, in all cases the molecular mass of the cross-reacting polypeptide falls in the range of 51-56 kDa. Only in Halobacterium halobium, bands at 66 and 68 kDa have been detected. In order to identify the cross-reacting polypeptides, the purified F1-ATPases of E. coli, chloroplasts and beef heart mitochondria have been tested.(ABSTRACT TRUNCATED AT 400 WORDS)Keywords
This publication has 45 references indexed in Scilit:
- A plasma‐membrane associated ATPase from the thermoacidophilic archaebacterium Sulfolobus acidocaldariusEuropean Journal of Biochemistry, 1987
- The respiratory system of Sulfolobus acidocaldarius, a thermoacidophilic archaebacteriumFEBS Letters, 1985
- What family of ATPases does the vacuolar H+‐ATPase belong to?FEBS Letters, 1985
- Primary structure and subunit stoichiometry of F1-ATPase from bovine mitochondriaJournal of Molecular Biology, 1985
- Use of monoclonal antibodies in immuno-electron microscopy for the determination of subunit stoichiometry in oligomeric enzymes: There are three α-subunits in the F1-ATPase of Escherichia coliJournal of Molecular Biology, 1984
- The proton-ATPase of bacteria and mitochondriaThe Journal of Membrane Biology, 1983
- The proton-translocating ATPase of the fungal plasma membraneBiochimica et Biophysica Acta (BBA) - Reviews on Bioenergetics, 1981
- Electrophoretic transfer of proteins from polyacrylamide gels to nitrocellulose sheets: procedure and some applications.Proceedings of the National Academy of Sciences, 1979
- Communication to the editors: An immunocolloid method for the electron microscopeImmunochemistry, 1971
- Cleavage of Structural Proteins during the Assembly of the Head of Bacteriophage T4Nature, 1970