Purification and properties of factors in yeast mitochondria stabilizing the F1F0-ATPase-inhibitor complex

• Published in: Journal of biochemistry (Tokyo) Vol. 95; no. 1; pp. 131 - 136
• Main Authors: Hashimoto, T, Yoshida, Y, Tagawa, K
• Format: Journal Article
• Language: English
• Published: Oxford Oxford University Press 1984
• Subjects: Adenosine Triphosphatases - antagonists & inhibitors; Adenosine Triphosphatases - metabolism; ATPase Inhibitory Protein; Biological and medical sciences; Cell structures and functions; Chromatography, High Pressure Liquid; Fundamental and applied biological sciences. Psychology; Fungal Proteins - isolation & purification; Fungal Proteins - metabolism; Mitochondria - metabolism; Mitochondria and cell respiration; Molecular and cellular biology; plant biochemistry; plant physiology; Protein Binding; Proteins - metabolism; Proton-Translocating ATPases; Saccharomyces cerevisiae - metabolism; Yeast; Purification; Hydrolase; Enzyme; Stabilization; ATPase; Enzyme inhibitor; F0F1-ATPase; Molecular weight; Mitochondria; Regulation(control); Oxidative phosphorylation; Physicochemical properties; Cell respiration
• ISSN: 0021-924X; 1756-2651
• DOI: 10.1093/oxfordjournals.jbchem.a134576

A previously found yeast-mitochondrial protein fraction stabilizing the inactivated complex between mitochondrial ATPase and intrinsic ATPase inhibitor (Hashimoto, T., et al. (1983) J. Biochem. 94, 715–720) was separated into two proteins by high performance liquid chromatography on a cation exchanger. The molecular weights of the factors were estimated to be 9,000 and 15,000 daltons by sodium dodecyl sulfate (SDS)-gel electrophoresis. Both factors were required to stabilize a complex of inhibitor and proton-translocating ATPase (F1F0-ATPase) either in its purified form or in mitochondrial membranes. On the other hand both factors together could not stabilize a complex of the inhibitor and F1-ATPase, suggesting that both factors act together with the F0-portion. The factors also facilitated very efficiently the binding of ATPase inhibitor to F1F0-ATPase in the presence of ATP and Mg2+. Both the 15,000 and 9,000 dalton stabilizing factors were hardly distinguishable from δ- and ε-subunit, respectively, on an SDS-gel electrophoregram, but immunodiffusion assay showed that neither factor was present in the purified F1-ATPase containing the δ- and ε-subunit.