FIGURE 8.

Outline of the StClC gating/transport process under (A) depolarized and (B) hyperpolarized membrane conditions. The four available sites are represented as large open circles. The smaller open circles represent Cl⁻ as it occupies one of the available sites. Glu¹⁴⁸ is shown occupying the S_ext site when it is unprotonated. In this state, its negative charge is represented by a smaller open circle with a minus sign inside it. In the protonated state (E148-H), the side chain is represented by a smaller open circle without a minus sign inside it.