title: Solubilization of adenosine triphosphatase from membranes of Escherichia coli: effect of p-aminobenzamidine.
abstract: The five subunits of the membrane-bound adenosine triphosphatase (F1) from Escherichia coli were identified on electrophoretograms of membranes which had been washed with a low-ionic-strength buffer containing the protease inhibitor p-aminobenzamidine. All of the subunits of the membrane-bound F1 appeared to have the same molecular weights and isoelectric points as those of the soluble F1, as judged by two-dimensional electrophoresis. p-Aminobenzamidine inhibited the solubilization of F1 rebound to F1-depleted membranes, and was found to inhibit the membrane-bound adenosine triphosphatase activity to a much greater extent than the solubilized activity. It is therefore unlikely that p-aminobenzamidine inhibits the solubilization of F1 by inhibiting a protease, as suggested previously by Cox et al. (G.B. Cox, J.A. Downie, D.R.H. Fayle, F. Gibson, and J. Radik, J. Bacteriol. 133:287--292, 1978).
mesh_terms: D000251:Adenosine Triphosphatases / Q000032:analysis* / Q000037:antagonists & inhibitors; D000578:Amidines / Q000494:pharmacology*; D001550:Benzamidines / Q000494:pharmacology*; D002462:Cell Membrane / Q000201:enzymology; D004305:Dose-Response Relationship, Drug; D004926:Escherichia coli / Q000201:enzymology*; D012995:Solubility
chemical_list: D000578:Amidines; D001550:Benzamidines; D000251:Adenosine Triphosphatases