[K+-dependent enzyme activity of H+-ATPase in the E. coli membrane]

It was shown that DCCD-sensitive ATPase activity of isolated membranes and preparations of F1F0 only from anaerobically grown E. coli depended on K+ activity. F1F0 include two additional proteins which correspond to the Trk system. The data improve the possibility to form supercomplex (F1F0-Trk) functioning as the H(+)-K(+)-pump.