Presentation description

Malaria is a deadly infectious disease that kills hundreds of thousands of people every year. It primarily impacts children and pregnant women in Sub-Saharan Africa. We study the causative agent of malaria, Plasmodium falciparum which contains a unique organelle called the apicoplast, a chloroplast like organelle without photosynthesis. It is known that doxycycline targets the apicoplast and kills parasite but current doses of doxycycline, 1 μM, kill parasites slowly over four days. However, increased concentrations, 10 μM, kill parasites faster over two days. We recently showed that if we add exogenous iron to parasites treated with 10 μM, but not 1 μM doxycycline, we could rescue parasites from death. We hypothesize that doxycycline interferes with iron utilization within the apicoplast. To test this, we have generated parasites that have an episomal copy of pyruvate dehydrogenase tagged with green fluorescent protein (PDH_GFP). We will test our hypothesis by treating tagged parasites in three different conditions: untreated, 10 μM doxycycline, and 10 μM doxycycline and exogenous iron. After lysis, we will run a western blot on parasite samples to confirm epsiomal expression of PDH_GFP and lipoylation of PDH. We expect to see normal lipoylation in untreated parasites. If doxycycline is impacting iron utilization in the apicoplast we expect that doxycycline treated parasites will not show lipoylation of PDH. However, in iron rescued parasites we expect to see lipoylation of PDH_GFP. Our findings will help us understand the mechanism of doxycycline and how iron is utilized in the apicoplast.