Chagas disease, leishmaniasis, and sleeping sickness affect 20 million people worldwide and lead to more than 50,000 deaths annually1. The diseases are caused by infection with the kinetoplastid parasites Trypanosoma cruzi, Leishmania spp. and Trypanosoma brucei spp., respectively. These parasites have similar biology and genomic sequence, suggesting that all three diseases could be cured with drug(s) modulating the activity of a conserved parasite target2. However, no such molecular targets or broad spectrum drugs have been identified to date. Here we describe a selective inhibitor of the kinetoplastid proteasome (GNF6702) with unprecedented in vivo efficacy, which cleared parasites from mice in all three models of infection. GNF6702 inhibits the kinetoplastid proteasome through a non-competitive mechanism, does not inhibit the mammalian proteasome or growth of mammalian cells, and is well-tolerated in mice. Our data provide genetic and chemical validation of the parasite proteasome as a promising therapeutic target for treatment of kinetoplastid infections, and underscore the possibility of developing a single class of drugs for these neglected diseases.

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Dephosphocoenzyme A (dephospho-CoA) kinase catalyzes the final step in coenzyme A biosynthesis, the phosphorylation of the 3-hydroxy group of the ribose sugar moiety. Wild-type dephospho-CoA kinase from Corynebacterium ammoniagenes was purified to homogeneity and subjected to N-terminal sequence analysis. A BLAST search identified a gene from Escherichia coli previously designated yacE encoding a highly homologous protein. Amplification of the gene and overexpression yielded recombinant dephospho-CoA kinase as a 22.6-kDa monomer. Enzyme assay and nuclear magnetic resonance analyses of the product demonstrated that the recombinant enzyme is indeed dephospho-CoA kinase. The activities with adenosine, AMP, and adenosine phosphosulfate were 4 to 8% of the activity with dephospho-CoA. Homologues of the E. coli dephospho-CoA kinase were identified in a diverse range of organisms.Coenzyme A (CoA) is an essential cofactor in a wide variety of biochemical pathways (1). It is estimated that about 4% of all enzymes use CoA or a thioester of CoA as a substrate (24). The final two steps in CoA biosynthesis are coupling of phosphopantetheine with ATP to form dephosphocoenzyme A (dephospho-CoA) and the subsequent phosphorylation of the 3Ј-hydroxyl group to form CoA ( Fig. 1) (3). Genes coding for six of the seven enzymes involved in the biosynthesis of phosphopantetheine have been identified (10,14,20,26). The final two reactions of CoA biosynthesis in mammalian cells were first attributed to a single bifunctional enzyme by Hoagland and Novelli (8). This was verified by Worrall and Tubbs, who purified a protein from pork liver that possessed both the phosphopantetheine adenylyltransferase and dephospho-CoA kinase activities (25). Subsequently, these two activities were shown to be part of a multifunctional enzyme complex in baker's yeast (5, 6). We first showed that the final two steps in CoA biosynthesis in Corynebacterium ammoniagenes (formerly Brevibacterium ammoniagenes) are catalyzed by distinct proteins that were readily separated by ion-exchange chromatography (12). The gene from Escherichia coli coding for phosphopantetheine adenylyltransferase was recently cloned, and the crystal structure of the enzyme was determined (7, 9). We report here purification of dephospho-CoA kinase from wildtype C. ammoniagenes and identification of the gene coding for a homologous protein in E. coli. This gene was cloned using PCR and overexpressed, and the resulting protein was purified. Enzyme assays and product characterization were used to show that the resulting recombinant protein is indeed dephosphoCoA kinase. The dephospho-CoA kinase gene is now designated coaE, based on the previous naming of the pantothenate kinase gene as coaA and of the phosphopantetheine adenylyltransferase gene as coaD (3, 7). MATERIALS AND METHODSMaterials. Dephospho-CoA, dilithium CoA, NADH, pyruvate kinase, lactic dehydrogenase, phosphoenolpyruvate, ATP, AMP, adenosine phosphosulfate (APS), DEAE Sepharose, and Q Sepharose were purchased from Sigma. A Sep...

FACILE is a language which symmetrically integrates concurrent and functional programming. It is a typed and statically scoped language. The language supports both function and process abstractions. Recursive functions may be defined and used within processes, and processes can be dynamically created during expression evaluation. Inter-process communication is by hand-shaking on typed channels. Typed channels, functions and process scripts are first-class values. In this paper, we present the "core" syntax of FACILE. We then describe an abstract machine C-FAM which executes concurrent processes evaluating functional style expressions. The operational definition of FACILE is presented by giving compilation rules from FACILE to C-FAM instructions, and execution rules for the abstract machine. An overview of the FACILE environment is also discussed.

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Fin-type field-effect transistors (FinFETs) are promising substitutes for bulk CMOS at the nanoscale. FinFETs are double-gate devices. The two gates of a FinFET can either be shorted for higher perfomance or independently controlled for lower leakage or reduced transistor count. This gives rise to a rich design space. This chapter provides an introduction to various interesting FinFET logic design styles, novel circuit designs, and layout considerations.

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Imidazopyridine 1 was identified from a phenotypic screen against P. falciparum (Pf) blood stages and subsequently optimized for activity on liver-stage schizonts of the rodent parasite P. yoelii (Py) as well as hypnozoites of the simian parasite P. cynomolgi (Pc). We applied these various assays to the cell-based lead optimization of the imidazopyrazines, exemplified by 3 (KAI407), and show that optimized compounds within the series with improved pharmacokinetic properties achieve causal prophylactic activity in vivo and may have the potential to target the dormant stages of P. vivax malaria.