Figure 6: Sodium ion enhances sulfamethazine efflux via YdaH.
From: Crystal structure of the Alcanivorax borkumensis YdaH transporter reveals an unusual topology
(a) Accumulation of radioactive sulfamethazine in BL21(DE3)ΔabgTΔpabA/pET15bΩydaH cells with difference sodium ion concentrations. Cells showed a significant decrease in [3H]-sulfamethazine accumulation in the presence of Na+. Error bars denote s.d. (n=3). ‘*’ indicates values of BL21(DE3)ΔabgTΔpabA/pET15b cells (control) that are significantly different from those of BL21(DE3)ΔabgTΔpabA/pET15bΩydaH expressing wild-type YdaH (P<0.001; Student’s t-test). (b) Efflux of radioactive sulfamethazine in BL21(DE3)ΔabgTΔpabA/pET15bΩydaH cells in the presence of sodium or potassium ions. The presence of Na+ significantly enhances [3H]-sulfamethazine efflux in BL21(DE3)ΔabgTΔpabA/pET15bΩydaH cells (black, control cells with the empty vector; red, 0 mM NaCl; magenta, 5 mM KCl; blue, 5 mM NaCl). Error bars denote the s.d. (n=3). ‘*’ indicates values of radioactive counts of intracellular [3H]-sulfamethazine in BL21(DE3)ΔabgTΔpabA/pET15bΩydaH cells with 5 mM NaCl (blue) that are significantly different from those of the control (black; P<0.001; Student’s t-test).
