Open AccessThe ATP Synthetase of Escherichia coli K12: Purification of the Enzyme and Reconstitution of Energy‐Transducing Activities
Author(s) -
FRIEDL Peter,
FRIEDL Christina,
SCHAIRER Hans Ulrich
Publication year - 1979
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1979.tb02046.x
Subject(s) - escherichia coli , enzyme , atpase , biochemistry , specific activity , atp synthase , gel electrophoresis , enzyme assay , chemistry , polyacrylamide gel electrophoresis , membrane , biology , microbiology and biotechnology , gene
The ATP synthetase of Escherichia coli K12 was purified by a simple procedure. The dicyclohexyl‐carbodiimide‐sensitive ATPase activity was enriched 21‐fold. The ATP synthetase preparation contained the eight polypeptides (α, β, γ, a, δ, b, ɛ, c) of the enzyme and a residual contamination (4% of the total protein) as shown by dodecylsulfate/polyacrylamide electrophoresis. The polypeptide c was specifically labelled with [ 14 C]dicyclohexylcarbodiimide. Energy‐transducing activities were reconstituted from soybean phospholipids and the purified enzyme. The proteoliposomes exhibited a significantly higher ATP‐ 32 P i exchange activity and a higher proton‐translocating activity as compared to the untreated membranes.