Beyond the MEP Pathway: A novel kinase required for prenol utilization by malaria parasites.

A proposed treatment for malaria is a combination of fosmidomycin and clindamycin. Both compounds inhibit the methylerythritol 4-phosphate (MEP) pathway, the parasitic source of farnesyl and geranylgeranyl pyrophosphate (FPP and GGPP, respectively). Both FPP and GGPP are crucial for the biosynthesis of several essential metabolites such as ubiquinone and dolichol, as well as for protein prenylation.

Plasmodium falciparum COQ2 gene encodes a functional 4-hydroxybenzoate polyprenyltransferase.

Ubiquinone (UQ) is a fundamental mitochondrial electron transport chain component. This compound is synthesized as the condensation of a p-substituted benzoic acid and a polyisoprenic moiety catalyzed by the enzyme 4-hydroxybenzoate polyprenyltransferase (EC 2.5.

The Biomedical Importance of the Missing Pathway for Farnesol and Geranylgeraniol Salvage.

Isoprenoids are the output of the polymerization of five-carbon, branched isoprenic chains derived from isopentenyl pyrophosphate (IPP) and its isomer, dimethylallyl pyrophosphate (DMAPP). Isoprene units are consecutively condensed to form longer structures such as farnesyl and geranylgeranyl pyrophosphate (FPP and GGPP, respectively), necessary for the biosynthesis of several metabolites. Polyprenyl transferases and synthases use polyprenyl pyrophosphates as their natural substrates; however, it is known that free polyprenols, such as farnesol (FOH), and geranylgeraniol (GGOH) can be incorporated into prenylated proteins, ubiquinone, cholesterol, and dolichols.

Isoprenoid alcohols utilization by malaria parasites.

is the etiological agent of human malaria, one of the most widespread diseases in tropical and subtropical regions. Drug resistance is one of the biggest problems in controlling the disease, which leads to the need to discover new antimalarial compounds. One of the most promissory drugs purposed is fosmidomycin, an inhibitor of the biosynthesis of isoprene units by the methylerythritol 4-phosphate (MEP) pathway, which in some cases failed in clinical studies.

Suitability of methods for Plasmodium falciparum cultivation in atmospheric air.

Background: One of the most controversial factors about malaria parasite culture is the gaseous composition used. The most commonly used one consists of a mixture poor in O2 and rich in CO2.

Objectives: The present study aimed to share standard methods from our research group simplifying Plasmodium falciparum cultures by employing atmospheric air (ATM) and reusable glass bottles under agitation.

Quantification of nerolidol in mouse plasma using gas chromatography-mass spectrometry.

Nerolidol is a naturally occurring sesquiterpene found in the essential oils of many types of flowers and plants. It is frequently used in cosmetics, as a food flavoring agent, and in cleaning products. In addition, nerolidol is used as a skin penetration enhancer for transdermal delivery of therapeutic drugs.

In vivo antimalarial activity and mechanisms of action of 4-nerolidylcatechol derivatives.

4-Nerolidylcatechol (1) is an abundant antiplasmodial metabolite that is isolated from Piper peltatum roots. O-Acylation or O-alkylation of compound 1 provides derivatives exhibiting improved stability and significant in vitro antiplasmodial activity. The aim of this work was to study the in vitro inhibition of hemozoin formation, inhibition of isoprenoid biosynthesis in Plasmodium falciparum cultures, and in vivo antimalarial activity of several 4-nerolidylcatechol derivatives.

Isoprenoid biosynthesis in the erythrocytic stages of Plasmodium falciparum.

The development of new drugs is one strategy for malaria control. Biochemical pathways localised in the apicoplast of the parasite, such as the synthesis of isoprenic precursors, are excellent targets because they are different or absent in the human host. Isoprenoids are a large and highly diverse group of natural products with many functions and their synthesis is essential for the parasite's survival.

In vitro and in vivo antiplasmodial activities of risedronate and its interference with protein prenylation in Plasmodium falciparum.

The increasing resistance of malarial parasites to almost all available drugs calls for the identification of new compounds and the detection of novel targets. Here, we establish the antimalarial activities of risedronate, one of the most potent bisphosphonates clinically used to treat bone resorption diseases, against blood stages of Plasmodium falciparum (50% inhibitory concentration [IC50] of 20.3±1.

Mass spectrometry analysis of polyisoprenoids alcohols and carotenoids via ESI(Li(+))-MS/MS.

Direct analysis of polyisoprenoid alcohols by electrospray ionization mass spectrometry (ESI-MS) often produces poor results requiring off-line time- and sample-consuming derivatization techniques. In this chapter, we describe a simple ESI-MS approach for the direct analysis of polyisoprenoid alcohols from biological samples. Lithium iodide is used to promote cationization by intense formation of [M+Li](+) adducts.

Protein dolichylation in Plasmodium falciparum.

We performed reverse-phase thin-layer chromatography and reverse-phase high-performance liquid chromatography (RP-HPLC) analysis of polyisoprenoids released by sulfonium-salt cleavage with methyl iodide from Plasmodium falciparum proteins labeled with [3H]FPP or [3H]GGPP and showed that a dolichol of 11 isoprene units is bound to 21-28-kDa protein clusters from trophozoite and schizont stages. The dolichol structure was confirmed by electrospray-ionization mass spectrometry analysis. Treatment with protein synthesis inhibitors and RP-HPLC analysis of the proteolytic digestion products from parasite proteins labeled with [35S]cysteine and [3H]FPP showed that the attachment of dolichol to protein is a post-translational event and probably occurs via a covalent bond to cysteine residues.

Electrospray ionization mass spectrometry analysis of polyisoprenoid alcohols via Li+ cationization.

Direct analysis of polyisoprenoids by electrospray ionization mass spectrometry (ESI-MS) often produces poor results requiring off-line time and sample-consuming derivatization techniques. We describe a simple ESI-MS approach for the direct analysis of polyisoprenoids using several dolichols and polyprenols with different chain sizes as proof-of-principle cases. Lithium iodide is used to promote cationization by intense formation of [M+Li]+ adducts.

Characterization of the isoprenoid chain of coenzyme Q in Plasmodium falciparum.

Little is known about isoprenoid biosynthesis in parasitic protozoa. The presence of dolichol and isoprenylated proteins has been detected in Plasmodium falciparum, but no studies are available about the biosynthesis of the isoprenic side chain attached to the benzoquinone ring of coenzyme Q. In the present study, using metabolic labelling with different intermediates, we demonstrated the presence of an active isoprenoid pathway for the biosynthesis of the isoprenic chain of coenzyme Q.