title: Structure, function and inhibition of the phosphoethanolamine methyltransferases of the human malaria parasites Plasmodium vivax and Plasmodium knowlesi.
abstract: Phosphoethanolamine methyltransferases (PMTs) catalyze the three-step methylation of phosphoethanolamine to form phosphocholine, a critical step in the synthesis of phosphatidylcholine in a select number of eukaryotes including human malaria parasites, nematodes and plants. Genetic studies in the malaria parasite Plasmodium falciparum have shown that the methyltransferase PfPMT plays a critical function in parasite development and differentiation. The presence of PMT orthologs in other malaria parasites that infect humans and their absence in mammals make them ideal targets for the development of selective antimalarials with broad specificity against different Plasmodium species. Here we describe the X-ray structures and biochemical properties of PMT orthologs from Plasmodium vivax and Plasmodium knowlesi and show that both enzymes are inhibited by amodiaquine and NSC158011, two drugs with potent antimalarial activity. Metabolic studies in a yeast mutant that relies on PkPMT or PvPMT for survival demonstrated that these compounds inhibit phosphatidylcholine biosynthesis from ethanolamine. Our structural and functional data provide insights into the mechanism of catalysis and inhibition of PMT enzymes and set the stage for a better design of more specific and selective antimalarial drugs.
authors.affiliation: Department of Internal Medicine, Yale University School of Medicine, New Haven CT, 06520 USA.
authors.forename: Aprajita
authors.initials: A
authors.lastname: Garg
authors.affiliation: 1] Department of Biochemistry, University of Illinois at Urbana-Champaign [2] Cornell High Energy Synchrotron Source, Cornell University.
authors.forename: Tiit
authors.initials: T
authors.lastname: Lukk
authors.affiliation: Department of Internal Medicine, Yale University School of Medicine, New Haven CT, 06520 USA.
authors.forename: Vidya
authors.initials: V
authors.lastname: Kumar
authors.affiliation: Basic Science Section, Department of Medicine, National Jewish Health, Denver, Colorado 80206.
authors.forename: Jae-Yeon
authors.initials: JY
authors.lastname: Choi
authors.affiliation: Department of Internal Medicine, Yale University School of Medicine, New Haven CT, 06520 USA.
authors.forename: Yoann
authors.initials: Y
authors.lastname: Augagneur
authors.affiliation: Basic Science Section, Department of Medicine, National Jewish Health, Denver, Colorado 80206.
authors.forename: Dennis R
authors.initials: DR
authors.lastname: Voelker
authors.affiliation: Department of Biochemistry, University of Illinois at Urbana-Champaign.
authors.forename: Satish
authors.initials: S
authors.lastname: Nair
authors.affiliation: Department of Internal Medicine, Yale University School of Medicine, New Haven CT, 06520 USA.
authors.forename: Choukri
authors.initials: C
authors.lastname: Ben Mamoun
mesh_terms: D000655:Amodiaquine / Q000737:chemistry / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004789:Enzyme Activation / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000737:chemistry / Q000494:pharmacology; D006801:Humans; D007700:Kinetics; D008780:Methyltransferases / Q000037:antagonists & inhibitors / Q000737:chemistry* / Q000378:metabolism*; D008958:Models, Molecular; D016790:Plasmodium knowlesi / Q000201:enzymology*; D010966:Plasmodium vivax / Q000201:enzymology*; D011487:Protein Conformation; D054730:Protein Interaction Domains and Motifs; D013329:Structure-Activity Relationship
chemical_list: D004791:Enzyme Inhibitors; D000655:Amodiaquine; D008780:Methyltransferases; C102844:phosphoethanolamine methyltransferase