Investigating the Novel Redox Active Thioredoxin-like Protein (PbTrxL-1) of the Malaria Parasite Plasmodium

Redox systems are an important component of the cellular metabolism. We have characterized a novel thioredoxin-like protein (TrxL-1) of the malaria parasite Plasmodium and have previously determined that the trxl-1 gene is specifically expressed during development of rodent malaria model parasite Plasmodium berghei in its mosquito vector. Here I describe the optimization of recombinant TrxL-1 expression and subsequent purification under denaturing conditions. Using biochemical assays, I demonstrate that TrxL-1 is redox active with the Plasmodium thioredoxin system. Recent reports have shown that in Toxoplasma gondii, a related species, the homologous TrxL-1 interacts with SAXO-1 which plays an important role in the regulation of microtubules. The Plasmodium homolog of SAXO-1 and its interaction with TrxL-1 is currently under investigation in our lab.