Fig. 8.
AcHV3 is proton selective and shows leak conductance of protons. (A) Typical whole-cell currents in the same cell ranging from pHo 6.0–8.0 at pHi 7.0, in 10 mV increments. Holding potential was −40 mV in each family. The dashed line shows the reversal potential. Whole-cell measurement from AcHV3 (n = 21). (B) Conductance-voltage plot of the current families in (A) (total conductance). (C) Activation kinetics from current families appears independent of pHo. (D) Proton leak currents are readily detectable by the shift in the baseline current at holding potential, during the solution exchange (blue arrow) to pHo 6 or pHo 8. Vhold in both exchanges is the same, but the test pulse voltage is different (as indicated).