Mitochondrial electron transport chain and parasite transport proteins (mETC/PTPs)

The Mitochondrial electron transport chain and parasite transport proteins represent a broad category of essential physiological systems in protozoan parasites, most notably Plasmodium species (Painter et al., 2007, Nature). The mitochondrial electron transport chain (mETC) is vital for parasite survival, primarily because it serves as a sink for electrons generated during de novo pyrimidine biosynthesis via dihydroorotate dehydrogenase, rather than solely for ATP production (Painter et al., 2007, Nature). Parasite transport proteins, including the Chloroquine Resistance Transporter (PfCRT) and various ion-motive ATPases like PfATP4, are responsible for maintaining electrochemical gradients, nutrient uptake, and the efflux of metabolic waste or drugs (Fidock et al., 2000, Molecular Cell; Rottmann et al., 2010, Science). Drugs such as atovaquone target the cytochrome bc1 complex (Complex III) of the mETC, disrupting the membrane potential and halting pyrimidine synthesis (Birth et al., 2014, Nature Communications). Meanwhile, drugs like cipargamin target PfATP4 to disrupt sodium homeostasis, leading to parasite lysis (Vaidya et al., 2014, Nature Communications). This target group is a cornerstone of antimalarial therapy, though its utility is constantly challenged by the emergence of point mutations that confer high-level drug resistance (Haldar et al., 2018, Nature Reviews Microbiology).

Other names

Parasite mitochondrial respiratory chainProtozoan membrane transportersApicomplexan mETCPlasmodium falciparum transport proteins

Inhibition of the cytochrome bc1 complex (Complex III) to disrupt mitochondrial membrane potential and pyrimidine biosynthesis; inhibition of P-type ATPases (e.g., PfATP4) to disrupt ion homeostasis; modulation of vacuolar transporters to alter drug accumulation (Painter et al., 2007, Nature; Rottmann et al., 2010, Science).