Is the Paracoccus halodenitrificans ATPase a chimeric enzyme?

Abstract

Membranes from Paracoccus halodenitrificans contain an ATPase that is most active in the absence of NaCl. The most unusual characteristic of the enzyme is its pattern of sensitivity to various inhibitors. Azide and rhodamine 6G, inhibitors of F 1F 0-ATPases, inhibit ATP hydrolysis as do bafilomycin A 1, concanamycin A (folimycin), N-ethylmaleimide, and p-chloromercuriphenylsulfonate which are inhibitors of vacuolar ATPases. This indiscriminate sensitivity suggests that this ATPase may be a hybrid and that caution should be exercised when using inhibition as a diagnostic for distinguishing between F 1F 0-ATPases and vacuolar ATPases.