Characterization of Leishmania major phosphatidylethanolamine methyltransferases LmjPEM1 and LmjPEM2 and their inhibition by choline analogs

摘要: Phosphatidylcholine (PC) is the most abundant phospholipid in membranes of human parasite Leishmania. It synthesized via two metabolic routes, de novo pathway that starts with uptake choline, and threefold methylation phosphatidylethanolamine. Choline was shown to be dispensable for Leishmania; thus, likely represents primary route PC production. Here, we have identified characterized phosphatidylethanolamine methyltransferases, LmjPEM1 LmjPEM2. Both enzymes are expressed promastigotes as well vertebrate form amastigotes, suggesting these methyltransferases important development throughout its life cycle. These maximally during log phase growth which correlates demand synthesis cell multiplication. Immunofluorescence studies combined fractionation both localized at endoplasmic reticulum membrane. Heterologous expression yeast has demonstrated LmjPEM2 complement choline auxotrophy phenotype a double null mutant lacking methyltransferase activity. catalyzes first, lesser extent, second reaction. In contrast, capacity add third methyl group onto yield (lyso)PC; it can also first group, albeit very low efficiency. Finally, using inhibition analogs miltefosine octadecyltrimethylammonium bromide potent inhibitors this pathway.