Regulation of GSH levels by GR activity and GSSG efflux. A. Western blot for GST expression using anti-P. falciparum GST antibody (α-GST, rabbit, 1:5000) and anti-P. falciparum 1-Cys peroxiredoxin antibody (α-TSAI, rabbit, 1:120 000) as loading control. B. GR expression level using anti-GR antibody (α-GR, rabbit, 1:30 000) and anti- P. falciparum 1-Cys peroxiredoxin (α-TSAI, rabbit, 1:120 000) as loading control. C. Relative expression of GST and GR in D10γGCS normalized to expression in wild-type D10 parasites. Results are means of 3 to 4 independent determinations ± SEM (*P < 0.05, unpaired Student's t-test). D. Efflux of total GSH/GSSG from D10 (●) and D10γGCS (▪). The efflux rate was significantly higher in D10γGCS (1844 ± 123 nmol h−1/1010 cells) than in wild-type D10 (1239 ± 74 nmol h−1/1010 cells) (unpaired Student's t-test, P = 0.01).