Interaction between the soluble F1 ATPase and its naturally occurring inhibitor protein. Studies using hydrophilic high-performance liquid chromatography and immunoelectron microscopy.
Binding of the isolated ATPase (F1) to its naturally occurring inhibitor protein was studied by two novel, independent techniques. High-pressure gel permeation chromatography revealed one tight binding site (Kd = 0.46 microM) for the inhibitor on F1, and a number of weak, non-specific sites. Use of an antibody directed against a non-binding region of the inhibitor protein demonstrated the formation of inhibitor/F1/immunoglobulin G complexes of 1:1:1 and 2:2:1 stoichiometry, but not of the putatively more stable cyclic 4:2:2 complexes. It was concluded that, despite the presence of three beta-subunits, only one site per F1 molecule is available for binding its inhibitor protein.
Harris
D A
DA
Husain
I
I
Jackson
P J
PJ
Lünsdorf
H
H
Schäfer
G
G
Tiedge
H
H
D000818:Animals; D002417:Cattle; D002851:Chromatography, High Pressure Liquid; D007158:Immunologic Techniques; D007700:Kinetics; D046911:Macromolecular Substances; D008297:Male; D008854:Microscopy, Electron; D009206:Myocardium / Q000201:enzymology; D011506:Proteins / Q000378:metabolism*; D006180:Proton-Translocating ATPases / Q000378:metabolism*; D000097795:ATPase Inhibitory Protein
D046911:Macromolecular Substances; D011506:Proteins; D006180:Proton-Translocating ATPases; D000097795:ATPase Inhibitory Protein