Salinipostin A (Sal A) is a potent antiplasmodial marine natural product with an undefined mechanism of action. Using a Sal A-derived activity-based probe, we identify its targets in the Plasmodium falciparum parasite. All of the identified proteins contain alpha/beta serine hydrolase domains and several are essential for parasite growth. One of the essential targets displays a high degree of homology to human monoacylglycerol lipase (MAGL) and is able to process lipid esters including a MAGL acylglyceride substrate. This Sal A target is inhibited by the anti-obesity drug Orlistat, which disrupts lipid metabolism. Resistance selections yielded parasites that showed only minor reductions in sensitivity and that acquired mutations in a PRELI domain-containing protein linked to drug resistance in Toxoplasma gondii. This inability to evolve efficient resistance mechanisms combined with the non-essentiality of human homologs makes the serine hydrolases identified here promising antimalarial targets.
Yoo E, Schulze CJ, Stokes BH, Onguka O, Yeo T, Mok S, Gnadig NF, Zhou Y, Kurita K, Foe IT, Terrell SM, Boucher MJ, Cieplak P, Kumpornsin K, Lee MCS, Linington RG, Long JZ, Uhlemann AC, Weerapana E, Fidock DA, Bogyo M (2020) The Antimalarial Natural Product Salinipostin A Identifies Essential alpha/beta Serine Hydrolases Involved in Lipid Metabolism in P. falciparum Parasites Cell Chemical Biology27: 143-157
Yoo E, Schulze CJ, Stokes BH, Onguka O, Yeo T, Mok S, Gnadig NF, Zhou Y, Kurita K, Foe IT, Terrell SM, Boucher MJ, Cieplak P, Kumpornsin K, Lee MCS, Linington RG, Long JZ, Uhlemann AC, Weerapana E, Fidock DA, Bogyo M (2020) Cell Chemical Biology27: 143-157
