Alternating electric fields stimulate ATP synthesis in Escherichia coli

External alternating electric fields of low intensity stimulated membrane bound ATP synthesis in starving Escherichia coli cells with electric field amplitudes of 2.5-50 V/cm and a frequency optimum at 100 Hz. The model of electrocon-formational coupling was used to analyze the frequency and amplitude responses of ATP synthesis. Two relaxation frequencies of the system were obtained at 44 Hz and 220 Hz, and an estimate of roughly 12 was obtained as the effective charge displacement for the catalytic cycle of ATP synthesis.