title: Conversion of Escherichia coli cell-produced metabolic energy into electric form.
abstract: The formation of membrane potential in energized E. coli cells has been investigated by means of ionic penetrants. The fluxes of anions and cations in opposite directions have been observed: anions moved out and cations moved into the cells. The energy-linked uptake of cations was stoichiometrically coupled with the outflow of H+ ions from the cells. The value of a membrane potential in the energized cells calculated from a distribution of permanent cations was in the range of -140 mV (inside minus). The uptake of penetrating cations by deenergized cells has been observed following the non-enzymatic generation of a membrane potential. The influx of synthetic and natural (lactose) penetrants collapsed the non-enzymatic membrane potential. The effect of lactose was sensitive to N-ethyl maleimide. These results are in favour of the conception that in the energized E. coli cells an energy-linked H+-pump generates a membrane potential which is a driving force for the transport of synthetic and some natural penetrants.
mesh_terms: D000332:Aerobiosis; D002258:Carbonyl Cyanide m-Chlorophenyl Hydrazone / Q000494:pharmacology; D002729:Chloromercuribenzoates / Q000494:pharmacology; D004735:Energy Transfer; D004926:Escherichia coli / Q000187:drug effects / Q000378:metabolism*; D005033:Ethylmaleimide / Q000494:pharmacology; D006863:Hydrogen-Ion Concentration; D007785:Lactose / Q000494:pharmacology; D008564:Membrane Potentials; D009154:Mutation; D010101:Oxygen Consumption; D011188:Potassium / Q000378:metabolism; D014320:Triphenylmethyl Compounds / Q000494:pharmacology; D014634:Valinomycin / Q000494:pharmacology
chemical_list: D002729:Chloromercuribenzoates; D014320:Triphenylmethyl Compounds; D014634:Valinomycin; D002258:Carbonyl Cyanide m-Chlorophenyl Hydrazone; D007785:Lactose; D005033:Ethylmaleimide; D011188:Potassium