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Abstract
The Apicomplexa phylum comprises thousands of distinct intracellular parasite species, including coccidians, haemosporidians, piroplasms, and cryptosporidia. These parasites are characterized by complex and divergent life cycles occupying a variety of host niches. Consequently, they exhibit distinct adaptations to the differences in nutritional availabilities, either relying on biosynthetic pathways or by salvaging metabolites from their host. Pantothenate (Pan, vitamin B5) is the precursor for the synthesis of an essential cofactor, coenzyme A (CoA), but among the apicomplexans, only the coccidian subgroup has the ability to synthesize Pan. While the pathway to synthesize CoA from Pan is largely conserved across all branches of life, there are differences in the redundancy of enzymes and possible alternative pathways to generate CoA from Pan. Impeding the scavenge of Pan and synthesis of Pan and CoA have been long recognized as potential targets for antimicrobial drug development, but in order to fully exploit these critical pathways, it is important to understand such differences. Recently, a potent class of pantothenamides (PanAms), Pan analogs, which target CoA-utilizing enzymes, has entered antimalarial preclinical development. The potential of PanAms to target multiple downstream pathways make them a promising compound class as broad antiparasitic drugs against other apicomplexans. In this review, we summarize the recent advances in understanding the Pan and CoA biosynthesis pathways, and the suitability of these pathways as drug targets in Apicomplexa, with a particular focus on the cyst-forming coccidian, Toxoplasma gondii, and the haemosporidian, Plasmodium falciparum.
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Affiliation(s)
- Laura E. de Vries
- Department of Medical Microbiology, Radboudumc Center for Infectious Diseases, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Matteo Lunghi
- Department of Microbiology & Molecular Medicine, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Aarti Krishnan
- Department of Microbiology & Molecular Medicine, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Taco W. A. Kooij
- Department of Medical Microbiology, Radboudumc Center for Infectious Diseases, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Dominique Soldati-Favre
- Department of Microbiology & Molecular Medicine, Faculty of Medicine, University of Geneva, Geneva, Switzerland
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2
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Tjhin ET, Howieson VM, Spry C, van Dooren GG, Saliba KJ. A novel heteromeric pantothenate kinase complex in apicomplexan parasites. PLoS Pathog 2021; 17:e1009797. [PMID: 34324601 PMCID: PMC8366970 DOI: 10.1371/journal.ppat.1009797] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 08/16/2021] [Accepted: 07/13/2021] [Indexed: 11/19/2022] Open
Abstract
Coenzyme A is synthesised from pantothenate via five enzyme-mediated steps. The first step is catalysed by pantothenate kinase (PanK). All PanKs characterised to date form homodimers. Many organisms express multiple PanKs. In some cases, these PanKs are not functionally redundant, and some appear to be non-functional. Here, we investigate the PanKs in two pathogenic apicomplexan parasites, Plasmodium falciparum and Toxoplasma gondii. Each of these organisms express two PanK homologues (PanK1 and PanK2). We demonstrate that PfPanK1 and PfPanK2 associate, forming a single, functional PanK complex that includes the multi-functional protein, Pf14-3-3I. Similarly, we demonstrate that TgPanK1 and TgPanK2 form a single complex that possesses PanK activity. Both TgPanK1 and TgPanK2 are essential for T. gondii proliferation, specifically due to their PanK activity. Our study constitutes the first examples of heteromeric PanK complexes in nature and provides an explanation for the presence of multiple PanKs within certain organisms.
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Affiliation(s)
- Erick T. Tjhin
- Research School of Biology, The Australian National University, Canberra, Australia
| | - Vanessa M. Howieson
- Research School of Biology, The Australian National University, Canberra, Australia
| | - Christina Spry
- Research School of Biology, The Australian National University, Canberra, Australia
| | - Giel G. van Dooren
- Research School of Biology, The Australian National University, Canberra, Australia
| | - Kevin J. Saliba
- Research School of Biology, The Australian National University, Canberra, Australia
- Medical School, The Australian National University, Canberra, Australia
- * E-mail:
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3
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Nurkanto A, Jeelani G, Santos HJ, Rahmawati Y, Mori M, Nakamura Y, Goto K, Saikawa Y, Annoura T, Tozawa Y, Sakura T, Inaoka DK, Shiomi K, Nozaki T. Characterization of Plasmodium falciparum Pantothenate Kinase and Identification of Its Inhibitors From Natural Products. Front Cell Infect Microbiol 2021; 11:639065. [PMID: 33768012 PMCID: PMC7985445 DOI: 10.3389/fcimb.2021.639065] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Accepted: 01/29/2021] [Indexed: 12/17/2022] Open
Abstract
Coenzyme A (CoA) is a well-known cofactor that plays an essential role in many metabolic reactions in all organisms. In Plasmodium falciparum, the most deadly among Plasmodium species that cause malaria, CoA and its biosynthetic pathway have been proven to be indispensable. The first and rate-limiting reaction in the CoA biosynthetic pathway is catalyzed by two putative pantothenate kinases (PfPanK1 and 2) in this parasite. Here we produced, purified, and biochemically characterized recombinant PfPanK1 for the first time. PfPanK1 showed activity using pantetheine besides pantothenate, as the primary substrate, indicating that CoA biosynthesis in the blood stage of P. falciparum can bypass pantothenate. We further developed a robust and reliable screening system to identify inhibitors using recombinant PfPanK1 and identified four PfPanK inhibitors from natural compounds.
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Affiliation(s)
- Arif Nurkanto
- Research Center for Biology, Indonesian Institute of Sciences (LIPI), Cibinong, Indonesia.,Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Ghulam Jeelani
- Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Herbert J Santos
- Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Yulia Rahmawati
- Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Mihoko Mori
- Kitasato Institute for Life Sciences, Kitasato University, Tokyo, Japan.,Biological Resource Center, National Institute of Technology and Evaluation (NITE), Chiba, Japan
| | - Yumi Nakamura
- Department of Applied Chemistry, Faculty of Science and Technology, Keio University, Yokohama, Japan
| | - Kana Goto
- Department of Applied Chemistry, Faculty of Science and Technology, Keio University, Yokohama, Japan
| | - Yoko Saikawa
- Department of Applied Chemistry, Faculty of Science and Technology, Keio University, Yokohama, Japan
| | - Takeshi Annoura
- Department of Parasitology, National Institute of Infectious Diseases (NIID), Tokyo, Japan
| | - Yuzuru Tozawa
- Graduate School of Science and Engineering, Saitama University, Saitama, Japan
| | - Takaya Sakura
- Department of Molecular Infection Dynamics, School of Tropical Medicine and Global Health, Institute of Tropical Medicine (NEKKEN), Nagasaki University, Nagasaki, Japan
| | - Daniel Ken Inaoka
- Department of Molecular Infection Dynamics, School of Tropical Medicine and Global Health, Institute of Tropical Medicine (NEKKEN), Nagasaki University, Nagasaki, Japan
| | - Kazuro Shiomi
- Kitasato Institute for Life Sciences, Kitasato University, Tokyo, Japan
| | - Tomoyoshi Nozaki
- Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
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4
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Domingo R, van der Westhuyzen R, Hamann AR, Mostert KJ, Barnard L, Paquet T, Tjhin ET, Saliba KJ, van Otterlo WAL, Strauss E. Overcoming synthetic challenges in targeting coenzyme A biosynthesis with the antimicrobial natural product CJ-15,801. Medchemcomm 2019; 10:2118-2125. [PMID: 32206243 DOI: 10.1039/c9md00312f] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Accepted: 10/16/2019] [Indexed: 11/21/2022]
Abstract
The biosynthesis of the essential metabolic cofactor coenzyme A (CoA) has been receiving increasing attention as a new target that shows potential to counter the rising resistance to established antimicrobials. In particular, phosphopantothenoylcysteine synthetase (PPCS)-the second CoA biosynthesis enzyme that is found as part of the bifunctional CoaBC protein in bacteria, but is monofunctional in eukaryotes-has been validated as a target through extensive genetic knockdown studies in Mycobacterium tuberculosis. Moreover, it has been identified as the molecular target of the fungal natural product CJ-15,801 that shows selective activity against Staphylococcus aureus and the malaria parasite Plasmodium falciparum. As such, CJ-15,801 and 4'-phospho-CJ-15,801 (its metabolically active form) are excellent tool compounds for use in the development of new antimicrobial PPCS inhibitors. Unfortunately, further study and analysis of CJ-15,801 is currently being hampered by several unique challenges posed by its synthesis. In this study we describe how these challenges were overcome by using a robust palladium-catalyzed coupling to form the key N-acyl vinylogous carbamate moiety with retention of stereochemistry, and by extensive investigation of protecting groups suited to the labile functional group combinations contained in this molecule. We also demonstrate that using TBAF for deprotection causes undesired off-target effects related to the presence of residual tertiary ammonium salts. Finally, we provide a new method for the chemoenzymatic preparation of 4'-phospho-CJ-15,801 on multi-milligram scale, after showing that chemical synthesis of the molecule is not practical. Taken together, the results of this study advances our pursuit to discover new antimicrobials that specifically target CoA biosynthesis and/or utilization.
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Affiliation(s)
- Riyad Domingo
- Department of Biochemistry , Stellenbosch University , Private Bag X1 , Matieland 7602 , South Africa .
| | - Renier van der Westhuyzen
- Department of Biochemistry , Stellenbosch University , Private Bag X1 , Matieland 7602 , South Africa .
| | - Anton R Hamann
- Department of Biochemistry , Stellenbosch University , Private Bag X1 , Matieland 7602 , South Africa .
| | - Konrad J Mostert
- Department of Biochemistry , Stellenbosch University , Private Bag X1 , Matieland 7602 , South Africa .
| | - Leanne Barnard
- Department of Biochemistry , Stellenbosch University , Private Bag X1 , Matieland 7602 , South Africa .
| | - Tanya Paquet
- Department of Biochemistry , Stellenbosch University , Private Bag X1 , Matieland 7602 , South Africa .
| | - Erick T Tjhin
- Research School of Biology , The Australian National University , Canberra , ACT , Australia
| | - Kevin J Saliba
- Research School of Biology , The Australian National University , Canberra , ACT , Australia.,Medical School , The Australian National University , Canberra , ACT , Australia
| | - Willem A L van Otterlo
- Department of Chemistry and Polymer Science , Stellenbosch University , Private Bag X1 , Matieland 7602 , South Africa
| | - Erick Strauss
- Department of Biochemistry , Stellenbosch University , Private Bag X1 , Matieland 7602 , South Africa .
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5
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Tjhin ET, Spry C, Sewell AL, Hoegl A, Barnard L, Sexton AE, Siddiqui G, Howieson VM, Maier AG, Creek DJ, Strauss E, Marquez R, Auclair K, Saliba KJ. Mutations in the pantothenate kinase of Plasmodium falciparum confer diverse sensitivity profiles to antiplasmodial pantothenate analogues. PLoS Pathog 2018; 14:e1006918. [PMID: 29614109 PMCID: PMC5882169 DOI: 10.1371/journal.ppat.1006918] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Accepted: 02/01/2018] [Indexed: 12/31/2022] Open
Abstract
The malaria-causing blood stage of Plasmodium falciparum requires extracellular pantothenate for proliferation. The parasite converts pantothenate into coenzyme A (CoA) via five enzymes, the first being a pantothenate kinase (PfPanK). Multiple antiplasmodial pantothenate analogues, including pantothenol and CJ-15,801, kill the parasite by targeting CoA biosynthesis/utilisation. Their mechanism of action, however, remains unknown. Here, we show that parasites pressured with pantothenol or CJ-15,801 become resistant to these analogues. Whole-genome sequencing revealed mutations in one of two putative PanK genes (Pfpank1) in each resistant line. These mutations significantly alter PfPanK activity, with two conferring a fitness cost, consistent with Pfpank1 coding for a functional PanK that is essential for normal growth. The mutants exhibit a different sensitivity profile to recently-described, potent, antiplasmodial pantothenate analogues, with one line being hypersensitive. We provide evidence consistent with different pantothenate analogue classes having different mechanisms of action: some inhibit CoA biosynthesis while others inhibit CoA-utilising enzymes. The coenzyme A (CoA) biosynthetic pathway is under investigation as a target for the development of drugs aimed at several infectious agents, including malaria parasites. To synthesise CoA, the parasite scavenges the essential precursor pantothenate (vitamin B5). Several pantothenate analogues possess potent (nM) activity against the parasite, but their exact mechanism of action is unknown. We have generated mutant parasites that are resistant or hypersensitive to various pantothenate analogues. These parasites harbour mutations in a gene we now show codes for the first enzyme in the CoA biosynthesis pathway. This enzyme is not the target of the analogues, but instead converts them into antimetabolites that, depending on the analogue, either inhibit a CoA biosynthesis enzyme or downstream CoA-utilising enzymes.
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Affiliation(s)
- Erick T. Tjhin
- Research School of Biology, The Australian National University, Canberra, Australia
| | - Christina Spry
- Research School of Biology, The Australian National University, Canberra, Australia
| | - Alan L. Sewell
- Department of Chemistry, University of Glasgow, Glasgow, United Kingdom
| | - Annabelle Hoegl
- Department of Chemistry, McGill University, Montreal, Quebec, Canada
| | - Leanne Barnard
- Department of Biochemistry, Stellenbosch University, Matieland, South Africa
| | - Anna E. Sexton
- Monash Institute of Pharmaceutical Sciences, Monash University, Melbourne, Australia
| | - Ghizal Siddiqui
- Monash Institute of Pharmaceutical Sciences, Monash University, Melbourne, Australia
| | - Vanessa M. Howieson
- Research School of Biology, The Australian National University, Canberra, Australia
| | - Alexander G. Maier
- Research School of Biology, The Australian National University, Canberra, Australia
| | - Darren J. Creek
- Monash Institute of Pharmaceutical Sciences, Monash University, Melbourne, Australia
| | - Erick Strauss
- Department of Biochemistry, Stellenbosch University, Matieland, South Africa
| | - Rodolfo Marquez
- Department of Chemistry, University of Glasgow, Glasgow, United Kingdom
- Department of Chemistry, Xi’an Jiaotong-Liverpool University, Suzhou, China
| | - Karine Auclair
- Department of Chemistry, McGill University, Montreal, Quebec, Canada
| | - Kevin J. Saliba
- Research School of Biology, The Australian National University, Canberra, Australia
- Medical School, The Australian National University, Canberra, Australia
- * E-mail:
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6
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Spry C, Sewell AL, Hering Y, Villa MV, Weber J, Hobson SJ, Harnor SJ, Gul S, Marquez R, Saliba KJ. Structure-activity analysis of CJ-15,801 analogues that interact with Plasmodium falciparum pantothenate kinase and inhibit parasite proliferation. Eur J Med Chem 2018; 143:1139-1147. [DOI: 10.1016/j.ejmech.2017.08.050] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Revised: 08/22/2017] [Accepted: 08/22/2017] [Indexed: 12/25/2022]
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7
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de Villiers M, Spry C, Macuamule CJ, Barnard L, Wells G, Saliba KJ, Strauss E. Antiplasmodial Mode of Action of Pantothenamides: Pantothenate Kinase Serves as a Metabolic Activator Not as a Target. ACS Infect Dis 2017; 3:527-541. [PMID: 28437604 DOI: 10.1021/acsinfecdis.7b00024] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
N-Substituted pantothenamides (PanAms) are pantothenate analogues with up to nanomolar potency against blood-stage Plasmodium falciparum (the most virulent species responsible for malaria). Although these compounds are known to target coenzyme A (CoA) biosynthesis and/or utilization, their exact mode of action (MoA) is still unknown. Importantly, PanAms that retain the natural β-alanine moiety are more potent than other variants, consistent with the involvement of processes that are selective for pantothenate (the precursor of CoA) or its derivatives. The transport of pantothenate and its phosphorylation by P. falciparum pantothenate kinase (PfPanK, the first enzyme of CoA biosynthesis) are two such processes previously highlighted as potential targets for the PanAms' antiplasmodial action. In this study, we investigated the effect of PanAms on these processes using their radiolabeled versions (synthesized here for the first time), which made possible the direct measurement of PanAm uptake by isolated blood-stage parasites and PanAm phosphorylation by PfPanK present in parasite lysates. We found that the MoA of PanAms does not involve interference with pantothenate transport and that inhibition of PfPanK-mediated pantothenate phosphorylation does not correlate with PanAm antiplasmodial activity. Instead, PanAms that retain the β-alanine moiety were found to be metabolically activated by PfPanK in a selective manner, forming phosphorylated products that likely inhibit other steps in CoA biosynthesis or are transformed into CoA antimetabolites that can interfere with CoA utilization. These findings provide direction for the ongoing development of CoA-targeted inhibitors as antiplasmodial agents with clinical potential.
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Affiliation(s)
- Marianne de Villiers
- Department of Biochemistry, Stellenbosch University, Stellenbosch 7600, South Africa
| | | | | | - Leanne Barnard
- Department of Biochemistry, Stellenbosch University, Stellenbosch 7600, South Africa
| | - Gordon Wells
- Department of Biochemistry, Stellenbosch University, Stellenbosch 7600, South Africa
| | | | - Erick Strauss
- Department of Biochemistry, Stellenbosch University, Stellenbosch 7600, South Africa
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Howieson VM, Tran E, Hoegl A, Fam HL, Fu J, Sivonen K, Li XX, Auclair K, Saliba KJ. Triazole Substitution of a Labile Amide Bond Stabilizes Pantothenamides and Improves Their Antiplasmodial Potency. Antimicrob Agents Chemother 2016; 60:7146-52. [PMID: 27645235 DOI: 10.1128/AAC.01436-16] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Accepted: 09/07/2016] [Indexed: 11/20/2022] Open
Abstract
The biosynthesis of coenzyme A (CoA) from pantothenate and the utilization of CoA in essential biochemical pathways represent promising antimalarial drug targets. Pantothenamides, amide derivatives of pantothenate, have potential as antimalarials, but a serum enzyme called pantetheinase degrades pantothenamides, rendering them inactive in vivo In this study, we characterize a series of 19 compounds that mimic pantothenamides with a stable triazole group instead of the labile amide. Two of these pantothenamides are active against the intraerythrocytic stage parasite with 50% inhibitory concentrations (IC50s) of ∼50 nM, and three others have submicromolar IC50s. We show that the compounds target CoA biosynthesis and/or utilization. We investigated one of the compounds for its ability to interact with the Plasmodium falciparum pantothenate kinase, the first enzyme involved in the conversion of pantothenate to CoA, and show that the compound inhibits the phosphorylation of [14C]pantothenate by the P. falciparum pantothenate kinase, but the inhibition does not correlate with antiplasmodial activity. Furthermore, the compounds are not toxic to human cells and, importantly, are not degraded by pantetheinase.
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9
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Saliba KJ, Spry C. Exploiting the coenzyme A biosynthesis pathway for the identification of new antimalarial agents: the case for pantothenamides. Biochem Soc Trans 2014; 42:1087-93. [PMID: 25110007 DOI: 10.1042/BST20140158] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Malaria kills more than half a million people each year. There is no vaccine, and recent reports suggest that resistance is developing to the antimalarial regimes currently recommended by the World Health Organization. New drugs are therefore needed to ensure malaria treatment options continue to be available. The intra-erythrocytic stage of the malaria parasite's life cycle is dependent on an extracellular supply of pantothenate (vitamin B5), the precursor of CoA (coenzyme A). It has been known for many years that proliferation of the parasite during this stage of its life cycle can be inhibited with pantothenate analogues. We have shown recently that pantothenamides, a class of pantothenate analogues with antibacterial activity, inhibit parasite proliferation at submicromolar concentrations and do so competitively with pantothenate. These compounds, however, are degraded, and therefore rendered inactive, by the enzyme pantetheinase (vanin), which is present in serum. In the present mini-review, we discuss the two strategies that have been put forward to overcome pantetheinase-mediated degradation of pantothenamides. The strategies effectively provide an opportunity for pantothenamides to be tested in vivo. We also put forward our 'blueprint' for the further development of pantothenamides (and other pantothenate analogues) as potential antimalarials.
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10
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Pett HE, Jansen PAM, Hermkens PHH, Botman PNM, Beuckens-Schortinghuis CA, Blaauw RH, Graumans W, van de Vegte-Bolmer M, Koolen KMJ, Rutjes FPJT, Dechering KJ, Sauerwein RW, Schalkwijk J. Novel pantothenate derivatives for anti-malarial chemotherapy. Malar J 2015; 14:169. [PMID: 25927675 PMCID: PMC4425855 DOI: 10.1186/s12936-015-0673-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Accepted: 04/04/2015] [Indexed: 02/02/2023] Open
Abstract
Background A number of synthetic pantothenate derivatives, such as pantothenamides, are known to inhibit the growth of the human malaria parasite Plasmodium falciparum, by interfering with the parasite Coenzyme A (CoA) biosynthetic pathway. The clinical use of pantothenamides is limited by their sensitivity to breakdown by ubiquitous human pantetheinases of the vanin family. Methods A number of pantothenate derivatives (pantothenones) with potent and specific inhibitory activity against mammalian vanins were tested in a proliferation assay of asexual P. falciparum blood stages alone, and in combination with pantothenamides. Results The vanin inhibitors were found to protect pantothenamides against breakdown by plasma vanins, thereby preserving the in vitro anti-malarial activity. Moreover, some of the vanin inhibitors showed in vitro anti-malarial activity in the low micromolar range. The most potent antimalarial in this series of compounds (RR8), was found to compete with pantothenate in a combination proliferation assay. No correlation, however, was found between anti-vanin and anti-malarial activity, nor was pantetheinase activity detected in P. falciparum extracts. Conclusions Growth inhibition is most likely due to competition with pantothenate, rather than pantetheinase inhibition. As vanin inhibitors of the pantothenone class are stable in biological fluids and are non-toxic to mammalian cells, they may represent novel pantothenate-based anti-malarials, either on their own or in combination with pantothenamides. Electronic supplementary material The online version of this article (doi:10.1186/s12936-015-0673-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Helmi E Pett
- Department of Medical Microbiology, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands.
| | - Patrick A M Jansen
- Department of Dermatology and Radboud Institute for Molecular Life Sciences, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands.
| | | | | | | | | | - Wouter Graumans
- Department of Medical Microbiology, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands.
| | - Marga van de Vegte-Bolmer
- Department of Medical Microbiology, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands.
| | | | - Floris P J T Rutjes
- Radboud University Nijmegen, Institute for Molecules and Materials, Nijmegen, The Netherlands. .,Pansynt B V, Nijmegen, The Netherlands.
| | | | - Robert W Sauerwein
- Department of Medical Microbiology, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands. .,TropIQ Health Sciences, Nijmegen, The Netherlands.
| | - Joost Schalkwijk
- Department of Dermatology and Radboud Institute for Molecular Life Sciences, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands. .,Pansynt B V, Nijmegen, The Netherlands.
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11
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Macuamule CJ, Tjhin ET, Jana CE, Barnard L, Koekemoer L, de Villiers M, Saliba KJ, Strauss E. A pantetheinase-resistant pantothenamide with potent, on-target, and selective antiplasmodial activity. Antimicrob Agents Chemother 2015; 59:3666-8. [PMID: 25845876 DOI: 10.1128/AAC.04970-14] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Accepted: 04/02/2015] [Indexed: 02/07/2023] Open
Abstract
Pantothenamides inhibit blood-stage Plasmodium falciparum with potencies (50% inhibitory concentration [IC50], ∼20 nM) similar to that of chloroquine. They target processes dependent on pantothenate, a precursor of the essential metabolic cofactor coenzyme A. However, their antiplasmodial activity is reduced due to degradation by serum pantetheinase. Minor modification of the pantothenamide structure led to the identification of α-methyl-N-phenethyl-pantothenamide, a pantothenamide resistant to degradation, with excellent antiplasmodial activity (IC50, 52 ± 6 nM), target specificity, and low toxicity.
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12
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Hoegl A, Darabi H, Tran E, Awuah E, Kerdo ESC, Habib E, Saliba KJ, Auclair K. Stereochemical modification of geminal dialkyl substituents on pantothenamides alters antimicrobial activity. Bioorg Med Chem Lett 2014; 24:3274-7. [PMID: 24986662 DOI: 10.1016/j.bmcl.2014.06.013] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2014] [Revised: 06/02/2014] [Accepted: 06/05/2014] [Indexed: 11/30/2022]
Abstract
Pantothenamides are N-substituted pantothenate derivatives which are known to exert antimicrobial activity through interference with coenzyme A (CoA) biosynthesis or downstream CoA-utilizing proteins. A previous report has shown that replacement of the ProR methyl group of the benchmark N-pentylpantothenamide with an allyl group (R-anti configuration) yielded one of the most potent antibacterial pantothenamides reported so far (MIC of 3.2 μM for both sensitive and resistant Staphylococcus aureus). We describe herein a synthetic route for accessing the corresponding R-syn diastereomer using a key diastereoselective reduction with Baker's yeast, and report on the scope of this reaction for modified systems. Interestingly, whilst the R-anti diastereomer is the only one to show antibacterial activity, the R-syn isomer proved to be significantly more potent against the malaria parasite (IC50 of 2.4±0.2 μM). Our research underlines the striking influence that stereochemistry has on the biological activity of pantothenamides, and may find utility in the study of various CoA-utilizing systems.
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Affiliation(s)
- Annabelle Hoegl
- Department of Chemistry, McGill University, 801 Sherbrooke Street West, Montréal, Québec H3A 0B8, Canada
| | - Hamed Darabi
- Department of Chemistry, McGill University, 801 Sherbrooke Street West, Montréal, Québec H3A 0B8, Canada
| | - Elisa Tran
- Department of Chemistry, McGill University, 801 Sherbrooke Street West, Montréal, Québec H3A 0B8, Canada
| | - Emelia Awuah
- Department of Chemistry, McGill University, 801 Sherbrooke Street West, Montréal, Québec H3A 0B8, Canada
| | - Eleanor S C Kerdo
- Research School of Biology, College of Medicine, Biology and Environment, The Australian National University, Canberra, Australian Capital Territory 0200, Australia
| | - Eric Habib
- Department of Chemistry, McGill University, 801 Sherbrooke Street West, Montréal, Québec H3A 0B8, Canada
| | - Kevin J Saliba
- Research School of Biology, College of Medicine, Biology and Environment, The Australian National University, Canberra, Australian Capital Territory 0200, Australia; Medical School, College of Medicine, Biology and Environment, The Australian National University, Canberra, Australian Capital Territory 0200, Australia
| | - Karine Auclair
- Department of Chemistry, McGill University, 801 Sherbrooke Street West, Montréal, Québec H3A 0B8, Canada.
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13
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de Villiers M, Macuamule C, Spry C, Hyun YM, Strauss E, Saliba KJ. Structural modification of pantothenamides counteracts degradation by pantetheinase and improves antiplasmodial activity. ACS Med Chem Lett 2013; 4:784-9. [PMID: 24900746 DOI: 10.1021/ml400180d] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2013] [Accepted: 06/17/2013] [Indexed: 11/30/2022] Open
Abstract
Pantothenamides are secondary or tertiary amides of pantothenic acid, the vitamin precursor of the essential cofactor and universal acyl carrier coenzyme A. A recent study has demonstrated that pantothenamides inhibit the growth of blood-stage Plasmodium falciparum with submicromolar potency by exerting an effect on pantothenic acid utilization, but only when the pantetheinase present in the growth medium has been inactivated. Here, we demonstrate that small modifications of the pantothenamide core structure are sufficient to counteract pantetheinase-mediated degradation and that the resulting pantothenamide analogues still inhibit the in vitro proliferation of P. falciparum by targeting a pantothenic acid-dependent process (or processes). Finally, we investigated the toxicity of the most potent analogues to human cells and show that the selectivity ratio exceeds 100 in one case. Taken together, these results provide further support for pantothenic acid utilization being a viable target for antimalarial drug discovery.
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Affiliation(s)
- Marianne de Villiers
- Department of Biochemistry, Stellenbosch University, Stellenbosch 7600, South Africa
| | - Cristiano Macuamule
- Department of Biochemistry, Stellenbosch University, Stellenbosch 7600, South Africa
| | | | | | - Erick Strauss
- Department of Biochemistry, Stellenbosch University, Stellenbosch 7600, South Africa
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14
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Augagneur Y, Jaubert L, Schiavoni M, Pachikara N, Garg A, Usmani-Brown S, Wesolowski D, Zeller S, Ghosal A, Cornillot E, Said HM, Kumar P, Altman S, Ben Mamoun C. Identification and functional analysis of the primary pantothenate transporter, PfPAT, of the human malaria parasite Plasmodium falciparum. J Biol Chem 2013; 288:20558-67. [PMID: 23729665 DOI: 10.1074/jbc.m113.482992] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The human malaria parasite Plasmodium falciparum is absolutely dependent on the acquisition of host pantothenate for its development within human erythrocytes. Although the biochemical properties of this transport have been characterized, the molecular identity of the parasite-encoded pantothenate transporter remains unknown. Here we report the identification and functional characterization of the first protozoan pantothenate transporter, PfPAT, from P. falciparum. We show using cell biological, biochemical, and genetic analyses that this transporter is localized to the parasite plasma membrane and plays an essential role in parasite intraerythrocytic development. We have targeted PfPAT to the yeast plasma membrane and showed that the transporter complements the growth defect of the yeast fen2Δ pantothenate transporter-deficient mutant and mediates the entry of the fungicide drug, fenpropimorph. Our studies in P. falciparum revealed that fenpropimorph inhibits the intraerythrocytic development of both chloroquine- and pyrimethamine-resistant P. falciparum strains with potency equal or better than that of currently available pantothenate analogs. The essential function of PfPAT and its ability to deliver both pantothenate and fenpropimorph makes it an attractive target for the development and delivery of new classes of antimalarial drugs.
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Affiliation(s)
- Yoann Augagneur
- Department of Medicine, Yale University School of Medicine, New Haven, Connecticut 06520, USA
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15
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Spry C, Macuamule C, Lin Z, Virga KG, Lee RE, Strauss E, Saliba KJ. Pantothenamides are potent, on-target inhibitors of Plasmodium falciparum growth when serum pantetheinase is inactivated. PLoS One 2013; 8:e54974. [PMID: 23405100 PMCID: PMC3566143 DOI: 10.1371/journal.pone.0054974] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2012] [Accepted: 12/21/2012] [Indexed: 12/26/2022] Open
Abstract
Growth of the virulent human malaria parasite Plasmodium falciparum is dependent on an extracellular supply of pantothenate (vitamin B(5)) and is susceptible to inhibition by pantothenate analogues that hinder pantothenate utilization. In this study, on the hunt for pantothenate analogues with increased potency relative to those reported previously, we screened a series of pantothenamides (amide analogues of pantothenate) against P. falciparum and show for the first time that analogues of this type possess antiplasmodial activity. Although the active pantothenamides in this series exhibit only modest potency under standard in vitro culture conditions, we show that the potency of pantothenamides is selectively enhanced when the parasite culture medium is pre-incubated at 37°C for a prolonged period. We present evidence that this finding is linked to the presence in Albumax II (a serum-substitute routinely used for in vitro cultivation of P. falciparum) of pantetheinase activity: the activity of an enzyme that hydrolyzes the pantothenate metabolite pantetheine, for which pantothenamides also serve as substrates. Pantetheinase activity, and thereby pantothenamide degradation, is reduced following incubation of Albumax II-containing culture medium for a prolonged period at 37°C, revealing the true, sub-micromolar potency of pantothenamides. Importantly we show that the potent antiplasmodial effect of pantothenamides is attenuated with pantothenate, consistent with the compounds inhibiting parasite proliferation specifically by inhibiting pantothenate and/or CoA utilization. Additionally, we show that the pantothenamides interact with P. falciparum pantothenate kinase, the first enzyme involved in converting pantothenate to coenzyme A. This is the first demonstration of on-target antiplasmodial pantothenate analogues with sub-micromolar potency, and highlights the potential of pantetheinase-resistant pantothenamides as antimalarial agents.
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Affiliation(s)
- Christina Spry
- Research School of Biology, College of Medicine, Biology and Environment, The Australian National University, Canberra, Australian Capital Territory, Australia
| | - Cristiano Macuamule
- Department of Biochemistry, Stellenbosch University, Matieland, Stellenbosch, South África
| | - Zhiyang Lin
- Research School of Biology, College of Medicine, Biology and Environment, The Australian National University, Canberra, Australian Capital Territory, Australia
| | - Kristopher G. Virga
- Department of Pharmaceutical and Administrative Sciences, Presbyterian College School of Pharmacy, Clinton, South Carolina, United States of America
- Department of Pharmaceutical Sciences, University of Tennessee Health Science Center, Memphis, Tennessee, United States of America
| | - Richard E. Lee
- Department of Pharmaceutical Sciences, University of Tennessee Health Science Center, Memphis, Tennessee, United States of America
- Department of Chemical Biology and Therapeutics, St. Jude Children’s Research Hospital, Memphis, Tennessee, United States of America
| | - Erick Strauss
- Department of Biochemistry, Stellenbosch University, Matieland, Stellenbosch, South África
| | - Kevin J. Saliba
- Research School of Biology, College of Medicine, Biology and Environment, The Australian National University, Canberra, Australian Capital Territory, Australia
- Medical School, College of Medicine, Biology and Environment, The Australian National University, Canberra, Australian Capital Territory, Australia
- * E-mail:
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16
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van der Westhuyzen R, Hammons JC, Meier JL, Dahesh S, Moolman WJA, Pelly SC, Nizet V, Burkart MD, Strauss E. The antibiotic CJ-15,801 is an antimetabolite that hijacks and then inhibits CoA biosynthesis. ACTA ACUST UNITED AC 2012; 19:559-71. [PMID: 22633408 DOI: 10.1016/j.chembiol.2012.03.013] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2011] [Revised: 03/13/2012] [Accepted: 03/27/2012] [Indexed: 01/21/2023]
Abstract
The natural product CJ-15,801 is an inhibitor of Staphylococcus aureus, but not other bacteria. Its close structural resemblance to pantothenic acid, the vitamin precursor of coenzyme A (CoA), and its Michael acceptor moiety suggest that it irreversibly inhibits an enzyme involved in CoA biosynthesis or utilization. However, its mode of action and the basis for its specificity have not been elucidated to date. We demonstrate that CJ-15,801 is transformed by the uniquely selective S. aureus pantothenate kinase, the first CoA biosynthetic enzyme, into a substrate for the next enzyme, phosphopantothenoylcysteine synthetase, which is inhibited through formation of a tight-binding structural mimic of its native reaction intermediate. These findings reveal CJ-15,801 as a vitamin biosynthetic pathway antimetabolite with a mechanism similar to that of the sulfonamide antibiotics and highlight CoA biosynthesis as a viable antimicrobial drug target.
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17
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Kashinath K, Swaroop PS, Reddy DS. A green synthetic route to antimalarial and antibacterial agent CJ-15,801 and its isomer cis-CJ-15,801. RSC Adv 2012. [DOI: 10.1039/c2ra01051h] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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18
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Abstract
The fast and efficient syntheses of pantothenic acid and the antiparasitic agent CJ-15,801 have been achieved starting from a common imide unit through the selective manipulation of enamide intermediates.
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Affiliation(s)
- Alan L Sewell
- WestCHEM, University of Glasgow, Joseph Black Building, University Avenue, Glasgow G12 8QQ, United Kingdom
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19
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Abstract
Pantothenic acid, a precursor of coenzyme A (CoA), is essential for the growth of pathogenic microorganisms. Since the structure of pantothenic acid was determined, many analogues of this essential metabolite have been prepared. Several have been demonstrated to exert an antimicrobial effect against a range of microorganisms by inhibiting the utilization of pantothenic acid, validating pantothenic acid utilization as a potential novel antimicrobial drug target. This review commences with an overview of the mechanisms by which various microorganisms acquire the pantothenic acid they require for growth, and the universal CoA biosynthesis pathway by which pantothenic acid is converted into CoA. A detailed survey of studies that have investigated the inhibitory activity of analogues of pantothenic acid and other precursors of CoA follows. The potential of inhibitors of both pantothenic acid utilization and biosynthesis as novel antibacterial, antifungal and antimalarial agents is discussed, focusing on inhibitors and substrates of pantothenate kinase, the enzyme catalysing the rate-limiting step of CoA biosynthesis in many organisms. The best strategies are considered for identifying inhibitors of pantothenic acid utilization and biosynthesis that are potent and selective inhibitors of microbial growth and that may be suitable for use as chemotherapeutic agents in humans.
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Affiliation(s)
- Christina Spry
- School of Biochemistry and Molecular Biology, The Australian National University, Canberra, Australia
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20
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Lehane AM, Marchetti RV, Spry C, van Schalkwyk DA, Teng R, Kirk K, Saliba KJ. Feedback inhibition of pantothenate kinase regulates pantothenol uptake by the malaria parasite. J Biol Chem 2007; 282:25395-405. [PMID: 17581817 DOI: 10.1074/jbc.m704610200] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
To survive, the human malaria parasite Plasmodium falciparum must acquire pantothenate (vitamin B5) from the external medium. Pantothenol (provitamin B5) inhibits parasite growth by competing with pantothenate for pantothenate kinase, the first enzyme in the coenzyme A biosynthesis pathway. In this study we investigated pantothenol uptake by P. falciparum and in doing so gained insights into the regulation of the parasite's coenzyme A biosynthesis pathway. Pantothenol was shown to enter P. falciparum-infected erythrocytes via two routes, the furosemide-inhibited "new permeation pathways" induced by the parasite in the infected erythrocyte membrane (the sole access route for pantothenate) and a second, furosemide-insensitive pathway. Having entered the erythrocyte, pantothenol is taken up by the intracellular parasite via a mechanism showing functional characteristics distinct from those of the parasite's pantothenate uptake mechanism. On reaching the parasite cytosol, pantothenol is phosphorylated and thereby trapped by pantothenate kinase, shown here to be under feedback inhibition control by coenzyme A. Furosemide reduced this inherent feedback inhibition by competing with coenzyme A for binding to pantothenate kinase, thereby increasing pantothenol uptake.
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Affiliation(s)
- Adele M Lehane
- School of Biochemistry and Molecular Biology, Medical School, The Australian National University, Canberra, ACT 0200, Australia
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21
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Müller S, Kappes B. Vitamin and cofactor biosynthesis pathways in Plasmodium and other apicomplexan parasites. Trends Parasitol 2007; 23:112-21. [PMID: 17276140 PMCID: PMC2330093 DOI: 10.1016/j.pt.2007.01.009] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2006] [Revised: 12/13/2006] [Accepted: 01/18/2007] [Indexed: 10/23/2022]
Abstract
Vitamins are essential components of the human diet. By contrast, the malaria parasite Plasmodium falciparum and related apicomplexan parasites synthesize certain vitamins de novo, either completely or in parts. The various biosynthesis pathways are specific to different apicomplexan parasites and emphasize the distinct requirements of these parasites for nutrients and growth factors. The absence of vitamin biosynthesis in humans implies that inhibition of the parasite pathways might be a way to interfere specifically with parasite development. However, the roles of biosynthesis and uptake of vitamins in the regulation of vitamin homeostasis in parasites needs to be established first. In this article, the procurement of vitamins B(1), B(5) and B(6) by Plasmodium and other apicomplexan parasites is discussed.
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Affiliation(s)
- Sylke Müller
- University of Glasgow, Glasgow Biomedical Research Centre, Division of Infection and Immunity, Wellcome Centre for Molecular Parasitology, 120 University Place, Glasgow G12 8TA, UK.
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22
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Spry C, Chai CLL, Kirk K, Saliba KJ. A class of pantothenic acid analogs inhibits Plasmodium falciparum pantothenate kinase and represses the proliferation of malaria parasites. Antimicrob Agents Chemother 2005; 49:4649-57. [PMID: 16251308 PMCID: PMC1280137 DOI: 10.1128/aac.49.11.4649-4657.2005] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2005] [Revised: 06/14/2005] [Accepted: 08/22/2005] [Indexed: 11/20/2022] Open
Abstract
The growth and proliferation of the human malaria parasite Plasmodium falciparum are dependent on the parasite's ability to obtain essential nutrients. One nutrient for which the parasite has an absolute requirement is the water-soluble vitamin pantothenic acid (vitamin B5). In this study, a series of pantothenic acid analogs which retain the 2,4-dihydroxy-3,3-dimethylbutyramide core of pantothenic acid but deviate in structure from one another and from pantothenic acid in the nature of the substituent attached to the amide nitrogen were synthesized using an efficient single-step synthetic route. Eight of 10 analogs tested inhibited the proliferation of intraerythrocytic P. falciparum parasites in vitro, doing so with 50% inhibitory concentrations between 15 and 200 microM. The compounds were generally selective, inhibiting the proliferation of a human cell line (the Jurkat cell line) only at concentrations severalfold higher than those required for inhibition of parasite growth. It was demonstrated that compounds in this series inhibited the phosphorylation of pantothenic acid by pantothenate kinase, the first step in the parasite's biosynthesis of the essential enzyme cofactor coenzyme A, doing so competitively, with K(i) values in the nanomolar range.
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Affiliation(s)
- Christina Spry
- School of Biochemistry and Molecular Biology, The Australian National University, Canberra ACT 0200, Australia
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