The role of potassium transport in the generation of a pH gradient in Escherichia coli.
The role of K+ transport in the generation of a pH gradient in Escherichia coli has been investigated. In K+-depleted cells, net K+ uptake dissipated delta psi (membrane potential) and led to an increase in delta pH (pH gradient). The magnitude of the delta pH formed bore a simple relationship to the net K+ uptake and was substantially independent of the respiratory rate. In K+-replete cells, generation of a pH gradient was again K+-dependent, although no net uptake of this cation occurred. The results are discussed in terms of K+ cycling, and it is suggested that delta pH is in part a function of the rate of cycling and independent of the respiratory rate.
D001692:Biological Transport; D004926:Escherichia coli / Q000378:metabolism* / Q000502:physiology; D006863:Hydrogen-Ion Concentration; D008564:Membrane Potentials; D010101:Oxygen Consumption; D011188:Potassium / Q000378:metabolism*; D013816:Thermodynamics
D011188:Potassium