Fig. 6: Ι Rescue of pH-sensitive CQ transport.
a Alanine mutagenesis of potential E207 interaction partners in the occluded conformation. Mutants were generated in the PfCRTDd2 background. Shown is a plot of R-values against the CQ transport activity at pH of 6.0 of the PfCRT variants indicated. Specific CQ transport was determined from an external CQ concentration of 50 µM. Each data point represents the mean ± SEM of n biologically independent samples. The number of biologically independent samples per mutant are: 14, PfCRTDd2; 9, E207A; 4, E327A; 4, K80A, 4, N84A; 3, E207K/K80E. b Replacement mutagenesis of E207. E207 was replaced by each of the 19 proteinogenic amino acids in the PfCRTDd2 background and the R-value was determined as a function of the CQ transport activity at a pH of 6.0. Note, only Asp and His (E207D and E207H variant) were able to reconstitute pH-sensitive CQ transport. Each data point represents the mean ± SEM of at least 3 biologically independent samples (range 3 to 14). c Effect of pH on E207H-mediated CQ transport. Each data point represents the mean ± SEM of 3 biologically independent samples. d E207H-mediated CQ transport kinetics at a pH of 4.5 and 6.0. Each data point represents the mean ± SEM of at least 3 to 4 biologically independent samples. Kinetic parameters are listed in Table 2. Source data are provided as a Source Data file86.
