Growth rate of P. falciparum D10 and D10Δgdhamutant parasites Parasites were synchronized and 24 h later diluted to 0.5% parasitaemia (day 1). Thin blood smears were taken daily and the parasite cultures were diluted 1:5 on day 2 and 4. The cultures were maintained at either 1% oxygen (A) or 20% oxygen (B). The experiment was performed in triplicate and the means ± S.D. are shown.