The Mg2+ and Ca2+ stimulated adenosine triphosphatase (ATPase) (EC 188.8.131.52; ATP phosphohydrolase) (bacterial coupling factor) was purified from two strains of E. coli by two different procedures: the method of Neslon, Kanner, and Gutnick, and by a modified procedure described in this paper. The ATPase purified from E. coli K12 (λ) by the first procedure had 4 subunits (α, β, γ, and ε). It did not bind to a deficient membrane, nor did it reconstitute ATP driven transhydrogenase activity. The modified procedure yielded 5 subunits (α, β, γ, δ, and ε). This ATPase could bind to a deficient membrane and reconstitute ATP driven transhydrogenase. This finding suggests that the δ subunit is required for the reaction with the membrane. The molecular weight of the 4 subunit ATPase was significantly lower than that of the 5 subunit ATPase, as judged by equilibrium centrifugation. The specific ATPase activities of both preparations were about the same. These two procedures were also applied to E. coli ML308 to 225.
|Original language||English (US)|
|Number of pages||5|
|Journal||Proceedings of the National Academy of Sciences of the United States of America|
|State||Published - 1974|
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