(A) Intracellular NG is coordinated by residues from the Sugar Porter and A motifs. A chloride ion (shown as spheres) neutralizes the A-motif. Hydrogen bonds are represented by yellow dashes (2.6–3.6 Å distances). The omit Fo-Fc density for NG is contoured in green at 3 σ. (B) Coordination of the chloride ion by residues of the A-motif. The Fo-Fc electron density, shown in green mesh, is contoured at 4 σ (top). The anomalous signal for the chemical chloride congener, bromide, shown in magenta mesh, is contoured at 4 σ (bottom).