The effect of CuCl2 on the efflux of inorganic phosphate from Escherichia coli

: The influence of CuCl2 on inorganic phosphate efflux from resting E. coli and those treated with glucose has been studied. Maintaining of high phosphate gradient on the membrane is possibly only in case of continuous supply of external metabolic energy. Treatment with CuCl2 does not lead to the increase in permeability of the resting cell membrane for phosphates, but it causes the efflux of phosphates in glucose-treated cells. The above data suggest that the efflux is determined by inhibition of energy influx into cell by CuCl2, not by damaging the cytoplasmic membrane.