Stoicheiometry of lactose–proton symport across the plasma membrane of Escherichia coli

Abstract

The rate of [14C]lactose inflow into anaerobic, non-metabolizing, Escherichia coli has been correlated with the rate of the simultaneous effective inflow of H+. It is shown that the initial rates of the two transport processes are essentially the same, and it is concluded that the two processes are strictly coupled with a 1:1 stoicheiometry.