Purification and properties of factors in yeast mitochondria stabilizing the F1F0-ATPase-inhibitor complex.
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 delta- and epsilon-subunit, respectively, on an SDS-gel electrophoregram, but immuno-diffusion assay showed that neither factor was present in the purified F1-ATPase containing the delta- and epsilon-subunit.
D000251:Adenosine Triphosphatases / Q000037:antagonists & inhibitors* / Q000378:metabolism; D002851:Chromatography, High Pressure Liquid; D005656:Fungal Proteins / Q000302:isolation & purification* / Q000378:metabolism; D008928:Mitochondria / Q000378:metabolism*; D011485:Protein Binding; D011506:Proteins / Q000378:metabolism*; D006180:Proton-Translocating ATPases; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D000097795:ATPase Inhibitory Protein
D000251:Adenosine Triphosphatases; D005656:Fungal Proteins; D011506:Proteins; D006180:Proton-Translocating ATPases; D000097795:ATPase Inhibitory Protein