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Wang J, Qu Z, Ma X, Olajide JS, Cai J. Cloning, expression, and functional identification of aquaporin genes from Eimeria tenella. Vet Parasitol 2024; 328:110153. [PMID: 38452532 DOI: 10.1016/j.vetpar.2024.110153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Revised: 02/28/2024] [Accepted: 02/28/2024] [Indexed: 03/09/2024]
Abstract
Avian coccidiosis, caused by Eimeria spp., is one of the major parasitic diseases in chicken. Aquaporins (AQP) are essential mediators of water regulation and nutritional intake in parasites, and it may be a suitable molecule for chemotherapeutic target and vaccine candidate. We identified two aquaporin genes in Eimeria tenella (EtAQP1 and EtAQP2) with their full sequence, and the expression profiles were analyzed across different stages of E. tenella life cycle. The expression of EtAQP1 and EtAQP2 in Xenopus oocytes renders them highly permeable for both water and glycerol. Sugar alcohols up to five carbons and urea pass the pore. The immunohistochemical analysis confirms the restriction of antiserum staining to the surface of transfected Xenopus oocytes. Like other AQP family, EtAQPs are transmembrane proteins that are likely important molecules that facilitate solute uptake for parasite intracellular growth and therapeutic targets.
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Affiliation(s)
- Jing Wang
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou 730000, China; Jiangsu Co-innovation Center for the Prevention and Control of Important Animal Infectious Disease and Zoonoses, Yangzhou University, Yangzhou 225009, China.
| | - Zigang Qu
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou 730000, China; Jiangsu Co-innovation Center for the Prevention and Control of Important Animal Infectious Disease and Zoonoses, Yangzhou University, Yangzhou 225009, China
| | - Xueting Ma
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou 730000, China; Jiangsu Co-innovation Center for the Prevention and Control of Important Animal Infectious Disease and Zoonoses, Yangzhou University, Yangzhou 225009, China
| | - Joshua Seun Olajide
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou 730000, China; Jiangsu Co-innovation Center for the Prevention and Control of Important Animal Infectious Disease and Zoonoses, Yangzhou University, Yangzhou 225009, China
| | - Jianping Cai
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou 730000, China; Jiangsu Co-innovation Center for the Prevention and Control of Important Animal Infectious Disease and Zoonoses, Yangzhou University, Yangzhou 225009, China.
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2
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PMRT1, a
Plasmodium
-Specific Parasite Plasma Membrane Transporter, Is Essential for Asexual and Sexual Blood Stage Development. mBio 2022; 13:e0062322. [PMID: 35404116 PMCID: PMC9040750 DOI: 10.1128/mbio.00623-22] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Plasmodium falciparum
-infected erythrocytes possess multiple compartments with designated membranes. Transporter proteins embedded in these membranes not only facilitate movement of nutrients, metabolites, and other molecules between these compartments, but also are common therapeutic targets and can confer antimalarial drug resistance.
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3
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de Oliveira LS, Alborghetti MR, Carneiro RG, Bastos IMD, Amino R, Grellier P, Charneau S. Calcium in the Backstage of Malaria Parasite Biology. Front Cell Infect Microbiol 2021; 11:708834. [PMID: 34395314 PMCID: PMC8355824 DOI: 10.3389/fcimb.2021.708834] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Accepted: 07/14/2021] [Indexed: 12/26/2022] Open
Abstract
The calcium ion (Ca2+) is a ubiquitous second messenger involved in key biological processes in prokaryotes and eukaryotes. In Plasmodium species, Ca2+ signaling plays a central role in the parasite life cycle. It has been associated with parasite development, fertilization, locomotion, and host cell infection. Despite the lack of a canonical inositol-1,4,5-triphosphate receptor gene in the Plasmodium genome, pharmacological evidence indicates that inositol-1,4,5-triphosphate triggers Ca2+ mobilization from the endoplasmic reticulum. Other structures such as acidocalcisomes, food vacuole and mitochondria are proposed to act as supplementary intracellular Ca2+ reservoirs. Several Ca2+-binding proteins (CaBPs) trigger downstream signaling. Other proteins with no EF-hand motifs, but apparently involved with CaBPs, are depicted as playing an important role in the erythrocyte invasion and egress. It is also proposed that a cross-talk among kinases, which are not members of the family of Ca2+-dependent protein kinases, such as protein kinases G, A and B, play additional roles mediated indirectly by Ca2+ regulation. This statement may be extended for proteins directly related to invasion or egress, such as SUB1, ERC, IMC1I, IMC1g, GAP45 and EBA175. In this review, we update our understanding of aspects of Ca2+-mediated signaling correlated to the developmental stages of the malaria parasite life cycle.
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Affiliation(s)
- Lucas Silva de Oliveira
- Laboratory of Biochemistry and Protein Chemistry, Department of Cell Biology, Institute of Biology, University of Brasilia, Brasilia, Brazil
- UMR 7245 MCAM, Molécules de Communication et Adaptation des Micro-organismes, Muséum National d’Histoire Naturelle, CNRS, Équipe Parasites et Protistes Libres, Paris, France
| | - Marcos Rodrigo Alborghetti
- Laboratory of Biochemistry and Protein Chemistry, Department of Cell Biology, Institute of Biology, University of Brasilia, Brasilia, Brazil
- Brazilian Biosciences National Laboratory, Brazilian Center for Research in Energy and Materials, Campinas, Brazil
| | - Renata Garcia Carneiro
- Laboratory of Biochemistry and Protein Chemistry, Department of Cell Biology, Institute of Biology, University of Brasilia, Brasilia, Brazil
| | - Izabela Marques Dourado Bastos
- Laboratory of Host-Pathogen Interaction, Department of Cell Biology, Institute of Biology, University of Brasilia, Brasilia, Brazil
| | - Rogerio Amino
- Unité Infection et Immunité Paludéennes, Institut Pasteur, Paris, France
| | - Philippe Grellier
- UMR 7245 MCAM, Molécules de Communication et Adaptation des Micro-organismes, Muséum National d’Histoire Naturelle, CNRS, Équipe Parasites et Protistes Libres, Paris, France
| | - Sébastien Charneau
- Laboratory of Biochemistry and Protein Chemistry, Department of Cell Biology, Institute of Biology, University of Brasilia, Brasilia, Brazil
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4
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Al Audhah N, Suhartono E, Sardjono TW, Fitri LE. Duration of Storage Reduced Erythrocytes Profiles and Plasmodium Viability in Donor Blood. J Blood Med 2021; 12:87-99. [PMID: 33654448 PMCID: PMC7910220 DOI: 10.2147/jbm.s276069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Accepted: 01/11/2021] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND Malaria screening for blood derived from any donors prior to transfusions is a standard procedure that should be performed; but, in fact, it is not routinely conducted. In case of the blood is infected with Plasmodium spp., the survival of parasites may be depending on, or even influencing, the profile of red blood cells (RBCs). METHODS This observational longitudinal study was conducted upon 55 bags of donor blood that randomly selected. Malaria infections were detected using Rapid Diagnostic Test/RDT with thin and thick blood smear confirmation. The changes of Plasmodium spp. viability and RBCs profiles, as well as other hematological parameters, were observed from the results of routine hematological examinations which were performed on days 1,7,14 and 21 of storage. RESULTS Among 55 blood samples, there were 17 and 38 bags, respectively, positive and negative for malaria, then used for analysis as the case and control groups. There were significant decreasing values (p<0.05) of all routine blood examination parameters of donor blood, started from days 1, 7, 14, 21, and 28. There were no differences in decreasing profiles between those infected and non-infected donor blood (p>0.05). On days 21 and 28 none of the positive samples still contained parasites. CONCLUSION Erythrocytes profiles of donor blood significantly decreased with the duration of storage, but were not influenced by the presence of Plasmodium spp.
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Affiliation(s)
- Nelly Al Audhah
- Doctoral Program of Medical Science, Faculty of Medicine, Universitas Brawijaya, Malang, Indonesia
- Department of Parasitology, Faculty of Medicine, Lambung Mangkurat University, Banjarmasin, Indonesia
| | - Eko Suhartono
- Department of Chemistry/Biochemistry, Faculty of Medicine, Lambung Mangkurat University, Banjarmasin, Indonesia
| | - Teguh Wahju Sardjono
- Department of Parasitology, Faculty of Medicine, Universitas Brawijaya, Malang, Indonesia
| | - Loeki Enggar Fitri
- Department of Parasitology, Faculty of Medicine, Universitas Brawijaya, Malang, Indonesia
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5
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Sardar R, Katyal N, Ahamad S, Jade DD, Ali S, Gupta D. In-silico profiling and structural insights into the impact of nSNPs in the P. falciparum acetyl-CoA transporter gene to understand the mechanism of drug resistance in malaria. J Biomol Struct Dyn 2020; 39:558-569. [PMID: 31903842 DOI: 10.1080/07391102.2020.1711807] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The continuous emergence of resistance to the available drugs poses major constraints in the development of effective therapeutics against malaria. Malaria drug resistance has been attributed to be the manifestation of numerous factors. For example, mutations in the parasite transporter protein acetyl-CoA transporter (Pfact) can remarkably affect its uptake affinity for a drug molecule against malaria, and hence enhance its susceptibility to resistance. To identify major contributors to its loss of functionality, we have thoroughly scrutinized eight such recently reported resistant mutants, via in-silico tools in terms of alterations in different properties. We performed molecular dynamics simulations of the selected Pfact mutants to gain deeper insights into the structural perturbation and dynamicity. Comparison of residue interaction network map of mutants with that of Wild type (WT) protein suggests structural changes as a result of the mutation(s) that translate into the weakening of intra-protein interactions, especially around the drug binding pocket. This, in turn, diminishes the affinity of drug molecules towards the binding site, which was validated by docking analysis. Finally, collating all the observations, we have delineated R108K mutant to deviate the most from WT protein, which, intriguingly suggests that replacing an amino acid with another of similar nature can even translate into greater functional effects as those with dissimilar substitutions.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Rahila Sardar
- Translational Bioinformatics Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, India.,Department of Biochemistry, Jamia Hamdard, New Delhi, India
| | - Nidhi Katyal
- Translational Bioinformatics Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, India
| | - Shahzaib Ahamad
- Translational Bioinformatics Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, India
| | - Dhananjay D Jade
- Translational Bioinformatics Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, India
| | - Shakir Ali
- Department of Biochemistry, Jamia Hamdard, New Delhi, India
| | - Dinesh Gupta
- Translational Bioinformatics Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, India
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6
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Sayers CP, Mollard V, Buchanan HD, McFadden GI, Goodman CD. A genetic screen in rodent malaria parasites identifies five new apicoplast putative membrane transporters, one of which is essential in human malaria parasites. Cell Microbiol 2017; 20. [DOI: 10.1111/cmi.12789] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2017] [Revised: 09/04/2017] [Accepted: 09/07/2017] [Indexed: 11/30/2022]
Affiliation(s)
- Claire P. Sayers
- School of BioSciences University of Melbourne Parkville Victoria Australia
| | - Vanessa Mollard
- School of BioSciences University of Melbourne Parkville Victoria Australia
| | - Hayley D. Buchanan
- School of BioSciences University of Melbourne Parkville Victoria Australia
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7
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Ni ZX, Cui JM, Zhang NZ, Fu BQ. Structural and evolutionary divergence of aquaporins in parasites (Review). Mol Med Rep 2017; 15:3943-3948. [PMID: 28440467 PMCID: PMC5436202 DOI: 10.3892/mmr.2017.6505] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Accepted: 02/28/2017] [Indexed: 11/05/2022] Open
Abstract
Aquaporins are ubiquitous proteins that belong to the major intrinsic protein family. Previous studies have indicated that aquaporins are involved in multiple physiological processes in parasites, such as nutrient absorption and end product efflux, and thus, would be promising pharmacological agents in the fight against parasite infection. In the present paper, the authors analyzed the evolutionary relationship of parasitic aquaporins by re‑constructing of a phylogenic tree using neighbor‑joining and maximum likelihood methods. In addition, the authors discussed the variation of the conserved functional sites impacting on the transportation of water molecules. The protein was concluded to be a potential drug target in parasites.
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Affiliation(s)
- Zi-Xin Ni
- College of Veterinary Medicine, China Agricultural University, Beijing 100083, P.R. China
| | - Jian-Min Cui
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu 730046, P.R. China
| | - Nian-Zhang Zhang
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu 730046, P.R. China
| | - Bao-Quan Fu
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu 730046, P.R. China
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8
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Weiner J, Kooij TWA. Phylogenetic profiles of all membrane transport proteins of the malaria parasite highlight new drug targets. MICROBIAL CELL 2016; 3:511-521. [PMID: 28357319 PMCID: PMC5348985 DOI: 10.15698/mic2016.10.534] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
In order to combat the on-going malaria epidemic, discovery of new drug targets
remains vital. Proteins that are essential to survival and specific to malaria
parasites are key candidates. To survive within host cells, the parasites need
to acquire nutrients and dispose of waste products across multiple membranes.
Additionally, like all eukaryotes, they must redistribute ions and organic
molecules between their various internal membrane bound compartments. Membrane
transport proteins mediate all of these processes and are considered important
mediators of drug resistance as well as drug targets in their own right.
Recently, using advanced experimental genetic approaches and streamlined life
cycle profiling, we generated a large collection of Plasmodium
berghei gene deletion mutants and assigned essential gene
functions, highlighting potential targets for prophylactic, therapeutic, and
transmission-blocking anti-malarial drugs. Here, we present a comprehensive
orthology assignment of all Plasmodium falciparum putative
membrane transport proteins and provide a detailed overview of the associated
essential gene functions obtained through experimental genetics studies in human
and murine model parasites. Furthermore, we discuss the phylogeny of selected
potential drug targets identified in our functional screen. We extensively
discuss the results in the context of the functional assignments obtained using
gene targeting available to date.
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Affiliation(s)
- January Weiner
- Department of Immunology, Max Planck Institute for Infection Biology, Berlin, Germany
| | - Taco W A Kooij
- Department of Medical Microbiology & Centre for Molecular and Biomolecular Informatics, Radboud Institute for Molecular Life Sciences, Radboud University Medical Centre, Nijmegen, The Netherlands
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9
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Farlora R, Valenzuela-Muñoz V, Chávez-Mardones J, Gallardo-Escárate C. Aquaporin family genes exhibit developmentally-regulated and host-dependent transcription patterns in the sea louse Caligus rogercresseyi. Gene 2016; 585:119-127. [DOI: 10.1016/j.gene.2016.03.035] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2015] [Revised: 03/11/2016] [Accepted: 03/18/2016] [Indexed: 01/21/2023]
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10
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Prati F, Goldman-Pinkovich A, Lizzi F, Belluti F, Koren R, Zilberstein D, Bolognesi ML. Quinone-amino acid conjugates targeting Leishmania amino acid transporters. PLoS One 2014; 9:e107994. [PMID: 25254495 PMCID: PMC4177859 DOI: 10.1371/journal.pone.0107994] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2014] [Accepted: 08/22/2014] [Indexed: 01/23/2023] Open
Abstract
The aim of the present study was to investigate the feasibility of targeting Leishmania transporters via appropriately designed chemical probes. Leishmania donovani, the parasite that causes visceral leishmaniasis, is auxotrophic for arginine and lysine and has specific transporters (LdAAP3 and LdAAP7) to import these nutrients. Probes 1–15 were originated by conjugating cytotoxic quinone fragments (II and III) with amino acids (i.e. arginine and lysine) by means of an amide linkage. The toxicity of the synthesized conjugates against Leishmania extracellular (promastigotes) and intracellular (amastigotes) forms was investigated, as well their inhibition of the relevant amino acid transporters. We observed that some conjugates indeed displayed toxicity against the parasites; in particular, 7 was identified as the most potent derivative (at concentrations of 1 µg/mL and 2.5 µg/mL residual cell viability was reduced to 15% and 48% in promastigotes and amastigotes, respectively). Notably, 6, while retaining the cytotoxic activity of quinone II, displayed no toxicity against mammalian THP1 cells. Transport assays indicated that the novel conjugates inhibited transport activity of lysine, arginine and proline transporters. Furthermore, our analyses suggested that the toxic conjugates might be translocated by the transporters into the cells. The non-toxic probes that inhibited transport competed with the natural substrates for binding to the transporters without being translocated. Thus, it is likely that 6, by exploiting amino acid transporters, can selectively deliver its toxic effects to Leishmania cells. This work provides the first evidence that amino acid transporters of the human pathogen Leishmania might be modulated by small molecules, and warrants their further investigation from drug discovery and chemical biology perspectives.
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Affiliation(s)
- Federica Prati
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum University of Bologna, Bologna, Italy
| | | | - Federica Lizzi
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum University of Bologna, Bologna, Italy
| | - Federica Belluti
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum University of Bologna, Bologna, Italy
| | - Roni Koren
- Faculty of Biology, Technion-Israel Institute of Technology, Haifa, Israel
| | - Dan Zilberstein
- Faculty of Biology, Technion-Israel Institute of Technology, Haifa, Israel
| | - Maria Laura Bolognesi
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum University of Bologna, Bologna, Italy
- * E-mail:
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11
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Parasite aquaporins: Current developments in drug facilitation and resistance. Biochim Biophys Acta Gen Subj 2014; 1840:1566-73. [DOI: 10.1016/j.bbagen.2013.10.014] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2013] [Revised: 10/02/2013] [Accepted: 10/06/2013] [Indexed: 01/15/2023]
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12
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13
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Batista R, García PA, Castro MA, Miguel Del Corral JM, Speziali NL, de P Varotti F, de Paula RC, García-Fernández LF, Francesch A, San Feliciano A, de Oliveira AB. Synthesis, cytotoxicity and antiplasmodial activity of novel ent-kaurane derivatives. Eur J Med Chem 2012; 62:168-76. [PMID: 23353738 DOI: 10.1016/j.ejmech.2012.12.010] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2012] [Revised: 12/06/2012] [Accepted: 12/07/2012] [Indexed: 10/27/2022]
Abstract
This paper reports on the syntheses and spectrometric characterisation of eleven novel ent-kaurane diterpenoids, including a complete set of (1)H, (13)C NMR and crystallographic data for two novel ent-kaurane diepoxides. Moreover, the antineoplastic cytotoxicity for kaurenoic acid and the majority of ent-kaurane derivatives were assessed in vitro against a panel of fourteen cancer cell lines, of which allylic alcohols were shown to be the most active compounds. The good in vitro antimalarial activity and the higher selectivity index values observed for some ent-kaurane epoxides against the chloroquine-resistant W2 clone of Plasmodium falciparum indicate that this class of natural products may provide new hits for the development of antimalarial drugs.
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Affiliation(s)
- Ronan Batista
- Departamento de Estudos Básicos e Instrumentais, Universidade Estadual do Sudoeste da Bahia, BR 415, Km 03, s/n°, 45.700-000 Itapetinga, Bahia, Brazil
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14
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Alam A, Goyal M, Iqbal MS, Pal C, Dey S, Bindu S, Maity P, Bandyopadhyay U. Novel antimalarial drug targets: hope for new antimalarial drugs. Expert Rev Clin Pharmacol 2012; 2:469-89. [PMID: 22112223 DOI: 10.1586/ecp.09.28] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Malaria is a major global threat, that results in more than 2 million deaths each year. The treatment of malaria is becoming extremely difficult due to the emergence of drug-resistant parasites, the absence of an effective vaccine, and the spread of insecticide-resistant vectors. Thus, malarial therapy needs new chemotherapeutic approaches leading to the search for new drug targets. Here, we discuss different approaches to identifying novel antimalarial drug targets. We have also given due attention to the existing validated targets with a view to develop novel, rationally designed lead molecules. Some of the important parasite proteins are claimed to be the targets; however, further in vitro or in vivo structure-function studies of such proteins are crucial to validate these proteins as suitable targets. The interactome analysis among apicoplast, mitochondrion and genomic DNA will also be useful in identifying vital pathways or proteins regulating critical pathways for parasite growth and survival, and could be attractive targets. Molecules responsible for parasite invasion to host erythrocytes and ion channels of infected erythrocytes, essential for intra-erythrocyte survival and stage progression of parasites are also becoming attractive targets. This review will discuss and highlight the current understanding regarding the potential antimalarial drug targets, which could be utilized to develop novel antimalarials.
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Affiliation(s)
- Athar Alam
- Division of Infectious Diseases and Immunology, Indian Institute of Chemical Biology, 4, Raja S.C. Mullick Road, Jadavpur, Kolkata-700032, West Bengal, India.
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15
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Beitz E. Aquaporins from pathogenic protozoan parasites: structure, function and potential for chemotherapy. Biol Cell 2012; 97:373-83. [PMID: 15901246 DOI: 10.1042/bc20040095] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Infectious diseases, caused by protozoa, such as malaria, sleeping sickness, Chagas' disease or leishmaniasis, are a global threat. The increase in the number of affected individuals and the rapid spread of drug-resistant strains call for specific novel strategies to combat human pathogenic parasites. In the search for novel drug targets, transport proteins for nutrients and metabolites of the parasite-host interface are getting into focus. The present review summarizes and discusses the currently available results on protozoan aquaporins. Various genes coding for aquaporin water and solute channels have been identified in the protozoan genomes and they are probable elements of the parasite's cell membrane. Phylogenetic analysis reveals that individual aquaporin genes are of bacterial or plant origin. So far, six protozoan aquaporins have been cloned and functionally characterized. Typically, these are bifunctional channels and pass water at intermediate to high rates as well as uncharged solutes. In the present review, amino acid compositions of the individual pore entries are compared and permeability properties are attributed to specific protein features. Furthermore, possible physiological roles in osmotic protection and metabolism are discussed. Finally, the potential of protozoan aquaporins for use as a target or entry pathway for chemotherapeutic compounds is reviewed.
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Affiliation(s)
- Eric Beitz
- Department of Pharmaceutical Chemistry, University of Tübingen, Morgenstelle 8, D-72076 Tübingen, Germany.
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16
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Dos Santos SC, Sá-Correia I. A genome-wide screen identifies yeast genes required for protection against or enhanced cytotoxicity of the antimalarial drug quinine. Mol Genet Genomics 2011; 286:333-46. [PMID: 21960436 DOI: 10.1007/s00438-011-0649-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2011] [Accepted: 09/16/2011] [Indexed: 11/28/2022]
Abstract
Quinine is used in the treatment of Plasmodium falciparum severe malaria. However, both the drug's mode of action and mechanisms of resistance are still poorly understood and subject to debate. In an effort to clarify these questions, we used the yeast Saccharomyces cerevisiae as a model for pharmacological studies with quinine. Following on a previous work that examined the yeast genomic expression program in response to quinine, we now explore a genome-wide screen for altered susceptibility to quinine using the EUROSCARF collection of yeast deletion strains. We identified 279 quinine-susceptible strains, among which 112 conferred a hyper-susceptibility phenotype. The expression of these genes, mainly involved in carbohydrate metabolism, iron uptake and ion homeostasis functions, is required for quinine resistance in yeast. Sixty-two genes whose deletion leads to increased quinine resistance were also identified in this screen, including several genes encoding ribosome protein subunits. These well-known potential drug targets in Plasmodium are associated with quinine action for the first time in this study. The suggested involvement of phosphate signaling and transport in quinine tolerance was also studied, and activation of phosphate starvation-responsive genes was observed under a mild-induced quinine stress. Finally, P. falciparum homology searches were performed for a selected group of 41 genes. Thirty-two encoded proteins possess homologs in the parasite, including subunits of a parasitic vacuolar H(+)-ATPase complex, ion and phosphate importers, and several ribosome protein subunits, suggesting that the results obtained in yeast are good candidates to be transposed and explored in a P. falciparum context.
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Affiliation(s)
- Sandra C Dos Santos
- IBB - Institute for Biotechnology and Bioengineering, Centre for Biological and Chemical Engineering, Instituto Superior Técnico, Av. Rovisco Pais, 1049-001, Lisbon, Portugal
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17
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Characterization of Leishmania donovani aquaporins shows presence of subcellular aquaporins similar to tonoplast intrinsic proteins of plants. PLoS One 2011; 6:e24820. [PMID: 21969862 PMCID: PMC3182166 DOI: 10.1371/journal.pone.0024820] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2011] [Accepted: 08/18/2011] [Indexed: 11/19/2022] Open
Abstract
Leishmania donovani, a protozoan parasite, resides in the macrophages of the mammalian host. The aquaporin family of proteins form important components of the parasite-host interface. The parasite-host interface could be a potential target for chemotherapy. Analysis of L. major and L. infantum genomes showed the presence of five aquaporins (AQPs) annotated as AQP9 (230aa), AQP putative (294aa), AQP-like protein (279aa), AQP1 (314aa) and AQP-like protein (596aa). We report here the structural modeling, localization and functional characterization of the AQPs from L. donovani. LdAQP1, LdAQP9, LdAQP2860 and LdAQP2870 have the canonical NPA-NPA motifs, whereas LdAQP putative has a non-canonical NPM-NPA motif. In the carboxyl terminal to the second NPA box of all AQPs except AQP1, a valine/alanine residue was found instead of the arginine. In that respect these four AQPs are similar to tonoplast intrinsic proteins in plants, which are localized to intracellular organelles. Confocal microscopy of L. donovani expressing GFP-tagged AQPs showed an intracellular localization of LdAQP9 and LdAQP2870. Real-time PCR assays showed expression of all aquaporins except LdAQP2860, whose level was undetectable. Three-dimensional homology modeling of the AQPs showed that LdAQP1 structure bears greater topological similarity to the aquaglyceroporin than to aquaporin of E. coli. The pore of LdAQP1 was very different from the rest in shape and size. The cavity of LdAQP2860 was highly irregular and undefined in geometry. For functional characterization, four AQP proteins were heterologously expressed in yeast. In the fps1Δ yeast cells, which lacked the key aquaglyceroporin, LdAQP1 alone displayed an osmosensitive phenotype indicating glycerol transport activity. However, expression of LdAQP1 and LdAQP putative in a yeast gpd1Δ strain, deleted for glycerol production, conferred osmosensitive phenotype indicating water transport activity or aquaporin function. Our analysis for the first time shows the presence of subcellular aquaporins and provides structural and functional characterization of aquaporins in Leishmania donovani.
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Boisson B, Lacroix C, Bischoff E, Gueirard P, Bargieri DY, Franke-Fayard B, Janse CJ, Ménard R, Baldacci P. The novel putative transporter NPT1 plays a critical role in early stages of Plasmodium berghei sexual development. Mol Microbiol 2011; 81:1343-57. [PMID: 21752110 DOI: 10.1111/j.1365-2958.2011.07767.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Transmission of Plasmodium species from a mammalian host to the mosquito vector requires the uptake, during an infected blood meal, of gametocytes, the precursor cells of the gametes. Relatively little is known about the molecular mechanisms involved in the developmental switch from asexual development to sexual differentiation or the maturation and survival of gametocytes. Here, we show that a gene coding for a novel putative transporter, NPT1, plays a crucial role in the development of Plasmodium berghei gametocytes. Parasites lacking NPT1 are severely compromised in the production of gametocytes and the rare gametocytes produced are unable to differentiate into fertile gametes. This is the earliest block in gametocytogenesis obtained by reverse genetics and the first to demonstrate the role of a protein with a putative transport function in sexual development. These results and the high degree of conservation of NPT1 in Plasmodium species suggest that this protein could be an attractive target for the development of novel drugs to block the spread of malaria.
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Affiliation(s)
- Bertrand Boisson
- Institut Pasteur, Biologie et Génétique du Paludisme, 75724 Paris, France.
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19
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Urbán P, Estelrich J, Cortés A, Fernàndez-Busquets X. A nanovector with complete discrimination for targeted delivery to Plasmodium falciparum-infected versus non-infected red blood cells in vitro. J Control Release 2011; 151:202-11. [PMID: 21223986 DOI: 10.1016/j.jconrel.2011.01.001] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2010] [Revised: 12/22/2010] [Accepted: 01/04/2011] [Indexed: 12/22/2022]
Abstract
Current administration methods of antimalarial drugs deliver the free compound in the blood stream, where it can be unspecifically taken up by all cells, and not only by Plasmodium-infected red blood cells (pRBCs). Nanosized carriers have been receiving special attention with the aim of minimizing the side effects of malaria therapy by increasing drug bioavailability and selectivity. Liposome encapsulation has been assayed for the delivery of compounds against murine malaria, but there is a lack of cellular studies on the performance of targeted liposomes in specific cell recognition and on the efficacy of cargo delivery, and very little data on liposome-driven antimalarial drug targeting to human-infecting parasites. We have used fluorescence microscopy to assess in vitro the efficiency of liposomal nanocarriers for the targeted delivery of their contents to pRBCs. 200-nm liposomes loaded with quantum dots were covalently functionalized with oriented, specific half-antibodies against P. falciparum late form-infected pRBCs. In less than 90min, liposomes dock to pRBC plasma membranes and release their cargo to the cell. 100.0% of late form-containing pRBCs and 0.0% of non-infected RBCs in P. falciparum cultures are recognized and permeated by the content of targeted immunoliposomes. Liposomes not functionalized with antibodies are also specifically directed to pRBCs, although with less affinity than immunoliposomes. In preliminary assays, the antimalarial drug chloroquine at a concentration of 2nM, ≥10 times below its IC(50) in solution, cleared 26.7±1.8% of pRBCs when delivered inside targeted immunoliposomes.
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Affiliation(s)
- Patricia Urbán
- Nanobioengineering Group, Institute for Bioengineering of Catalonia, Baldiri Reixac 10-12, Barcelona, Spain
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20
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Bobbala D, Alesutan I, Föller M, Tschan S, Huber SM, Lang F. Protective effect of amiodarone in malaria. Acta Trop 2010; 116:39-44. [PMID: 20510873 DOI: 10.1016/j.actatropica.2010.05.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2009] [Revised: 05/20/2010] [Accepted: 05/20/2010] [Indexed: 01/07/2023]
Abstract
According to previous observations, amiodarone triggers suicidal erythrocyte death or eryptosis, which is characterized by cell shrinkage and exposure of phosphatidylserine at the erythrocyte surface. Eryptosis may in turn accelerate the clearance of Plasmodium-infected erythrocytes. The present study tested whether amiodarone augments phosphatidylserine exposure of Plasmodium-infected erythrocytes, interferes with the development of parasitemia and thus influences the course of malaria. The in vitro infection of human erythrocytes with Plasmodium falciparum (strain BinH) increased annexin V-binding, an effect significantly augmented by amiodarone (10 microM). Amiodarone further significantly decreased intraerythrocytic DNA/RNA content (> or =5 microM) and in vitro parasitemia (> or =1 microM). Following infection of mice with Plasmodiumberghei ANKA by intraperitoneal injection of parasitized murine erythrocytes (1x10(6)) amiodarone (intraperitoneal 50mg/kg b.w.) significantly decreased the parasitemia and increased the survival of P. berghei-infected mice (from 0% to 70% 26 days after infection). Moreover, treatment with amiodarone significantly increased the percentage of PS-exposing infected erythrocytes. In conclusion, amiodarone inhibits intraerythrocytic growth of P. falciparum, enhances suicidal death of infected erythrocytes, decreases parasitemia following P. berghei infection and supports host survival during malaria.
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Affiliation(s)
- Diwakar Bobbala
- Department of Physiology, University of Tübingen, Gmelinstrasse 5, D-72076 Tübingen, Germany
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21
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Jemmely NY, Niang M, Preiser PR. Small variant surface antigens and Plasmodium evasion of immunity. Future Microbiol 2010; 5:663-82. [PMID: 20353305 DOI: 10.2217/fmb.10.21] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Antigenic variation at the Plasmodium-infected erythrocyte surface plays a critical role in malaria disease severity and host immune evasion. Our current understanding of the role of Plasmodium variant surface antigens in antigenic variation and immune evasion is largely limited to the extensive work carried out on the Plasmodium falciparum var gene family. Although homologues of var genes are not present in other malaria species, small variant gene families comprising the rif and stevor genes in P. falciparum and the pir genes in Plasmodium vivax, Plasmodium knowlesi and the rodent malaria Plasmodium chabaudi, Plasmodium berghei and Plasmodium yoelii also show features suggesting a role in antigenic variation and immune evasion. In this article, we highlight our current understanding of these variant antigens and provide insights on the mechanisms developed by malaria parasites to effectively avoid the host immune response and establish chronic infection.
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Affiliation(s)
- Noelle Yvonne Jemmely
- Nanyang Technological University, School of Biological Sciences, 60 Nanyang Drive, Singapore 637551, Singapore.
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22
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Aponte-Santamaría C, Hub JS, de Groot BL. Dynamics and energetics of solute permeation through the Plasmodium falciparum aquaglyceroporin. Phys Chem Chem Phys 2010; 12:10246-54. [DOI: 10.1039/c004384m] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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23
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Kun JF, de Carvalho EG. Novel therapeutic targets in Plasmodium falciparum: aquaglyceroporins. Expert Opin Ther Targets 2009; 13:385-94. [PMID: 19335062 DOI: 10.1517/14728220902817839] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
BACKGROUND Malaria is caused by the intracellular parasite Plasmodium falciparum. The constant need for novel malaria therapies is due to the development of resistance against existing drugs. OBJECTIVE To summarise attempts to investigate parasitic aquaporins as drug targets in malaria. METHODS Starting with a summary of the history of malaria we present aquaporin structure and function relationships. Potential interactions of inhibitors with plasmodial AQP (PfAQP) are discussed. PfAQP blockage is examined in the light of recent work on knock-out parasites. Since PfAQP is able to transport other small solutes the parasites are sensitive to other compounds which are harmless to the human host. RESULTS/CONCLUSIONS Total blockage of PfAQP may not lead to the death of the parasite but application of PfAQP as a vehicle for toxic substances may be a further pathway for research.
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Affiliation(s)
- Jürgen F Kun
- Department of Parasitology, Institute for Tropical Medicine, Tübingen, Germany.
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24
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Fadiel A, Isokpehi RD, Stambouli N, Hamza A, Benammar-Elgaaied A, Scalise TJ. Protozoan parasite aquaporins. Expert Rev Proteomics 2009; 6:199-211. [PMID: 19385945 DOI: 10.1586/epr.09.10] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Protozoan parasites are a major threat to human health with millions of fatalities worldwide, especially in nonindustrialized countries. Currently, there is no cure for many of these parasitic diseases. Consequently, there is an imperative to find treatment targets and develop novel drugs based on the proteins encoded in the genomes of these parasites. Aquaporins, members of membrane proteins discovered and characterized within the past 20 years, are the mechanism through which water is transported through living membranes. The presence of aquaporins explains disease etiology related to water physiology and presents new pharmacogenomic targets. In this article, we review the literature on aquaporins found in Apicomplexan, Kinetoplastida and Microsporidia parasites as potential drug targets. Furthermore, by analyzing protein motion dynamics, we identify impediments that need to be surmounted for developing effective drugs targeting the aquaglyceroporin of Plasmodium falciparum, the causative agent of the most fatal form of human malaria.
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Affiliation(s)
- Ahmed Fadiel
- Department of OBGYN, New York University School of Medicine, Bellevue Hospital Center, New York, NY 10016, USA.
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25
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Plasmodium falciparum: Growth response to potassium channel blocking compounds. Exp Parasitol 2008; 120:280-5. [DOI: 10.1016/j.exppara.2008.07.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2008] [Revised: 07/22/2008] [Accepted: 07/23/2008] [Indexed: 11/23/2022]
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Hedfalk K, Pettersson N, Öberg F, Hohmann S, Gordon E. Production, characterization and crystallization of the Plasmodium falciparum aquaporin. Protein Expr Purif 2008; 59:69-78. [DOI: 10.1016/j.pep.2008.01.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2007] [Revised: 12/17/2007] [Accepted: 01/13/2008] [Indexed: 12/23/2022]
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Waller KL, McBride SM, Kim K, McDonald TV. Characterization of two putative potassium channels in Plasmodium falciparum. Malar J 2008; 7:19. [PMID: 18218136 PMCID: PMC2263067 DOI: 10.1186/1475-2875-7-19] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2007] [Accepted: 01/24/2008] [Indexed: 11/23/2022] Open
Abstract
Background Potassium channels are essential for cell survival and participate in the regulation of cell membrane potential and electrochemical gradients. During its lifecycle, Plasmodium falciparum parasites must successfully traverse widely diverse environmental milieus, in which K+ channel function is likely to be critical. Dramatically differing conditions will be presented to the parasite in the mosquito mid-gut, red blood cell (RBC) cytosol and the human circulatory system. Methods In silico sequence analyses identified two open-reading frames in the P. falciparum genome that are predicted to encode for proteins with high homology to K+ channels. To further analyse these putative channels, specific antisera were generated and used in immunoblot and immunofluorescence analyses of P. falciparum-infected RBCs. Recombinant genome methods in cultured P. falciparum were used to create genetic knock outs of each K+ channel gene to asses the importance of their expression. Results Immunoblot and IFA analyses confirmed the expression of the two putative P. falciparum K+ channels (PfK1 and PfK2). PfK1 is expressed in all asexual stage parasites, predominantly in late stages and localizes to the RBC membrane. Conversely, PfK2 is predominantly expressed in late schizont and merozoite stage parasites and remains primarily localized to the parasite. Repeated attempts to knockout PfK1 and PfK2 expression by targeted gene disruption proved unsuccessful despite evidence of recombinant gene integration, indicating that pfk1 and pfk2 are apparently refractory to genetic disruption. Conclusion Putative K+ channel proteins PfK1 and PfK2 are expressed in cultured P. falciparum parasites with differing spatial and temporal patterns. Eventual functional characterization of these channels may reveal future pharmacological targets.
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Affiliation(s)
- Karena L Waller
- Department of Medicine (Cardiology), Albert Einstein College of Medicine, 1300 Morris Park Ave., Bronx NY 10461, USA.
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28
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Sherman IW. References. ADVANCES IN PARASITOLOGY 2008. [DOI: 10.1016/s0065-308x(08)00430-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Henry RI, Martin RE, Howitt SM, Kirk K. Localisation of a candidate anion transporter to the surface of the malaria parasite. Biochem Biophys Res Commun 2007; 363:288-91. [PMID: 17870052 DOI: 10.1016/j.bbrc.2007.08.116] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2007] [Accepted: 08/18/2007] [Indexed: 11/28/2022]
Abstract
PfSulP, encoded by the human malaria parasite Plasmodium falciparum, is a member of the sulphate permease family of anion transporter proteins. By transfecting the parasite with an epitope-tagged version of PfSulP, and detecting via western blot and indirect immunofluorescent assay microscopy, we show that PfSulP is localised to the surface of the intraerythrocytic parasite, where it is postulated to play a role in the flux of anions across the parasite plasma membrane.
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Affiliation(s)
- Roselani I Henry
- School of Biochemistry and Molecular Biology, The Australian National University, Canberra ACT 0200, Australia
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30
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Wang P, Wang Q, Sims PF, Hyde JE. Characterisation of exogenous folate transport in Plasmodium falciparum. Mol Biochem Parasitol 2007; 154:40-51. [PMID: 17509698 PMCID: PMC1906846 DOI: 10.1016/j.molbiopara.2007.04.002] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2007] [Revised: 04/03/2007] [Accepted: 04/03/2007] [Indexed: 12/02/2022]
Abstract
Folate salvage by Plasmodium falciparum is an important source of key cofactors, but little is known about the underlying mechanism. Using synchronised parasite cultures, we observed that uptake of this dianionic species against the negative-inward electrochemical gradient is highly dependent upon cell-cycle stage, temperature and pH, but not on mono- or divalent metal ions. Energy dependence was tested with different sugars; glucose was necessary for folate import, although fructose was also able to function in this role, unlike sugars that cannot be processed through the glycolytic pathway. Import into both infected erythrocytes and free parasites was strongly inhibited by the anion-channel blockers probenecid and furosemide, which are likely to be acting predominantly on specific folate transporters in both cases. Import was not affected by high concentrations of the antifolate drugs pyrimethamine and sulfadoxine, but was inhibited by the close folate analogue methotrexate. The pH optimum for folate uptake into infected erythrocytes was 6.5–7.0. Dinitrophenol and nigericin, which strongly facilitate the equilibration of H+ ions across biological membranes and thus abolish or substantially reduce the proton gradient, inhibited folate uptake profoundly. The ATPase inhibitor concanamycin A also greatly reduced folate uptake, further demonstrating a link to ATP-powered proton transport. These data strongly suggest that the principal folate uptake pathway in P. falciparum is specific, highly regulated, dependent upon the proton gradient across the parasite plasma membrane, and is likely to be mediated by one or more proton symporters.
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Affiliation(s)
| | | | | | - John E. Hyde
- Corresponding author. Tel.: +44 161 306 4185; fax: +44 161 306 5201.
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Templeton TJ. Whole-genome natural histories of apicomplexan surface proteins. Trends Parasitol 2007; 23:205-12. [PMID: 17350340 DOI: 10.1016/j.pt.2007.03.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2006] [Revised: 02/01/2007] [Accepted: 03/02/2007] [Indexed: 11/19/2022]
Abstract
The natural histories of free-living and pathogenic protozoans have been described in over a century of studies, spanning a range of disciplines such as microscopic, cellular, taxonomic, pathological, clinical and molecular. Only in the last decade has this landscape of work benefited from the availability of whole-genome nucleotide sequence data. For many pathogens, it is now possible to overlay analyses of protein repertoires onto the current spectrum of knowledge. This article illuminates protozoan natural histories, particularly the rapidly evolving and highly adaptive direct physical interface of apicomplexan parasites and their hosts, by providing a brief introduction to the origin and phylogenetic distribution of parasite-encoded surface proteins and their component domains.
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Affiliation(s)
- Thomas J Templeton
- Weill Cornell Medical College, Department of Microbiology and Immunology, 1300 York Avenue, Box 62, New York, NY 10021, USA.
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Duranton C, Akkaya C, Brand VB, Tanneur V, Lang F, Huber SM. Artemisinin inhibits cation currents in malaria-infected human erythrocytes. NANOMEDICINE-NANOTECHNOLOGY BIOLOGY AND MEDICINE 2007; 1:143-9. [PMID: 17292071 DOI: 10.1016/j.nano.2005.03.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2005] [Accepted: 03/31/2005] [Indexed: 10/25/2022]
Abstract
BACKGROUND Previous patch-clamp studies have demonstrated inwardly and outwardly rectifying anion currents, ClC-2 Cl- currents, and nonselective Ca(++)-permeable cation currents in Plasmodium falciparum-infected human erythrocytes. METHODS The current work studied the effect of the potent antimalarial drug artemisinin on the P falciparum infection-induced whole cell currents in human erythrocyte. RESULTS Artemisinin had no significant effect on the outwardly rectifying anion currents but inhibited the cation-selective currents with an apparent half-maximal inhibitory concentration of < or =10 micromol/L. CONCLUSION Because artemisinin reportedly inhibits the asexual parasite amplification with much higher potency, the antimalarial action of the drug cannot be attributed to the artemisinin effect on the cation currents. However, artemisinin may be used as a pharmacologic tool to dissect different current fractions in P falciparum-infected erythrocytes.
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Abstract
Synthesis de novo, acquisition by salvage and interconversion of purines and pyrimidines represent the fundamental requirements for their eventual assembly into nucleic acids as nucleotides and the deployment of their derivatives in other biochemical pathways. A small number of drugs targeted to nucleotide metabolism, by virtue of their effect on folate biosynthesis and recycling, have been successfully used against apicomplexan parasites such as Plasmodium and Toxoplasma for many years, although resistance is now a major problem in the prevention and treatment of malaria. Many targets not involving folate metabolism have also been explored at the experimental level. However, the unravelling of the genome sequences of these eukaryotic unicellular organisms, together with increasingly sophisticated molecular analyses, opens up possibilities of introducing new drugs that could interfere with these processes. This review examines the status of established drugs of this type and the potential for further exploiting the vulnerability of apicomplexan human pathogens to inhibition of this key area of metabolism.
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Affiliation(s)
- John E Hyde
- Manchester Interdisciplinary Biocentre, Faculty of Life Sciences, University of Manchester, 131 Princess Street, Manchester M1 7ND, UK.
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Kelly JX, Winter RW, Braun TP, Osei-Agyemang M, Hinrichs DJ, Riscoe MK. Selective killing of the human malaria parasite Plasmodium falciparum by a benzylthiazolium dye. Exp Parasitol 2006; 116:103-10. [PMID: 17266952 PMCID: PMC1965281 DOI: 10.1016/j.exppara.2006.12.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2006] [Revised: 11/30/2006] [Accepted: 12/06/2006] [Indexed: 11/25/2022]
Abstract
Malaria is an infectious disease caused by protozoan parasites of the genus Plasmodium. The most virulent form of the disease is caused by Plasmodium falciparum which infects hundreds of millions of people and is responsible for the deaths of 1-2 million individuals each year. An essential part of the parasitic process is the remodeling of the red blood cell membrane and its protein constituents to permit a higher flux of nutrients and waste products into or away from the intracellular parasite. Much of this increased permeability is due to a single type of broad specificity channel variously called the new permeation pathway (NPP), the nutrient channel, and the Plasmodial surface anion channel (PSAC). This channel is permeable to a range of low molecular weight solutes both charged and uncharged, with a strong preference for anions. Drugs such as furosemide that are known to block anion-selective channels inhibit PSAC. In this study, we have investigated a dye known as benzothiocarboxypurine, BCP, which had been studied as a possible diagnostic aid given its selective uptake by P. falciparum infected red cells. We found that the dye enters parasitized red cells via the furosemide-inhibitable PSAC, forms a brightly fluorescent complex with parasite nucleic acids, and is selectively toxic to infected cells. Our study describes an antimalarial agent that exploits the altered permeability of Plasmodium-infected red cells as a means to killing the parasite and highlights a chemical reagent that may prove useful in high throughput screening of compounds for inhibitors of the channel.
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Affiliation(s)
- Jane X. Kelly
- Medical Research Service, RD-33, Department of Veterans Affairs Medical Center, 3710 SW U.S. Veterans Hospital Road, Portland, OR, USA 97239
- Department of Chemistry, Portland State University, Portland, Oregon, 97207-0751
| | - Rolf W. Winter
- Medical Research Service, RD-33, Department of Veterans Affairs Medical Center, 3710 SW U.S. Veterans Hospital Road, Portland, OR, USA 97239
- Department of Chemistry, Portland State University, Portland, Oregon, 97207-0751
| | - Theodore P. Braun
- Medical Research Service, RD-33, Department of Veterans Affairs Medical Center, 3710 SW U.S. Veterans Hospital Road, Portland, OR, USA 97239
| | - Myralyn Osei-Agyemang
- Medical Research Service, RD-33, Department of Veterans Affairs Medical Center, 3710 SW U.S. Veterans Hospital Road, Portland, OR, USA 97239
| | - David J. Hinrichs
- Medical Research Service, RD-33, Department of Veterans Affairs Medical Center, 3710 SW U.S. Veterans Hospital Road, Portland, OR, USA 97239
| | - Michael K. Riscoe
- Medical Research Service, RD-33, Department of Veterans Affairs Medical Center, 3710 SW U.S. Veterans Hospital Road, Portland, OR, USA 97239
- Department of Chemistry, Portland State University, Portland, Oregon, 97207-0751
- Mailing Address: *Michael Riscoe, Ph.D., Medical Research Service, RD-33, Veterans Affairs Medical Center, 3710 SW U.S. Veterans Hospital Road, Portland, Oregon 97239 Phone Number: 503-721-7885/Telefacsimile: 503-402-2817/e-mail:
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Beitz E. Aquaporin Water and Solute Channels from Malaria Parasites and Other Pathogenic Protozoa. ChemMedChem 2006; 1:587-92. [PMID: 16892397 DOI: 10.1002/cmdc.200500105] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Eric Beitz
- Department of Pharmaceutical Chemistry, University of Tübingen, Auf der Morgenstelle 8, 72076 Tübingen, Germany.
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Mullin KA, Lim L, Ralph SA, Spurck TP, Handman E, McFadden GI. Membrane transporters in the relict plastid of malaria parasites. Proc Natl Acad Sci U S A 2006; 103:9572-7. [PMID: 16760253 PMCID: PMC1480448 DOI: 10.1073/pnas.0602293103] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Malaria parasites contain a nonphotosynthetic plastid homologous to chloroplasts of plants. The parasite plastid synthesizes fatty acids, heme, iron sulfur clusters and isoprenoid precursors and is indispensable, making it an attractive target for antiparasite drugs. How parasite plastid biosynthetic pathways are fuelled in the absence of photosynthetic capture of energy and carbon was not clear. Here, we describe a pair of parasite transporter proteins, PfiTPT and PfoTPT, that are homologues of plant chloroplast innermost membrane transporters responsible for moving phosphorylated C3, C5, and C6 compounds across the plant chloroplast envelope. PfiTPT is shown to be localized in the innermost membrane of the parasite plastid courtesy of a cleavable N-terminal targeting sequence. PfoTPT lacks such a targeting sequence, but is shown to localize in the outermost parasite plastid membrane with its termini projecting into the cytosol. We have identified these membrane proteins in the parasite plastid and determined membrane orientation for PfoTPT. PfiTPT and PfoTPT are proposed to act in tandem to transport phosphorylated C3 compounds from the parasite cytosol into the plastid. Thus, the transporters could shunt glycolytic derivatives of glucose scavenged from the host into the plastid providing carbon, reducing equivalents and ATP to power the organelle.
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Affiliation(s)
- Kylie A. Mullin
- *Plant Cell Biology Research Centre, School of Botany, University of Melbourne, Victoria 3010, Australia; and
| | - Liting Lim
- *Plant Cell Biology Research Centre, School of Botany, University of Melbourne, Victoria 3010, Australia; and
| | - Stuart A. Ralph
- *Plant Cell Biology Research Centre, School of Botany, University of Melbourne, Victoria 3010, Australia; and
| | - Timothy P. Spurck
- *Plant Cell Biology Research Centre, School of Botany, University of Melbourne, Victoria 3010, Australia; and
| | - Emanuela Handman
- The Walter and Eliza Hall Institute of Medical Research, Parkville 3050, Australia
| | - Geoffrey I. McFadden
- *Plant Cell Biology Research Centre, School of Botany, University of Melbourne, Victoria 3010, Australia; and
- To whom correspondence should be addressed. E-mail:
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37
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Lanzer M, Wickert H, Krohne G, Vincensini L, Braun Breton C. Maurer's clefts: A novel multi-functional organelle in the cytoplasm of Plasmodium falciparum-infected erythrocytes. Int J Parasitol 2006; 36:23-36. [PMID: 16337634 DOI: 10.1016/j.ijpara.2005.10.001] [Citation(s) in RCA: 104] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2005] [Revised: 09/23/2005] [Accepted: 10/04/2005] [Indexed: 10/25/2022]
Abstract
Discovered in 1902 by Georg Maurer as a peculiar dotted staining pattern observable by light microscopy in the cytoplasm of erythrocytes infected with the human malarial parasite Plasmodium falciparum, the function of Maurer's clefts have remained obscure for more than a century. The growing interest in protein sorting and trafficking processes in malarial parasites has recently aroused the Maurer's clefts from their deep slumber. Mounting evidence suggests that Maurer's clefts are a secretory organelle, which the parasite establishes within its host erythrocyte, but outside its own confines, to route parasite proteins across the host cell cytoplasm to the erythrocyte surface where they play a role in nutrient uptake and immune evasion processes. Moreover, Maurer's clefts seem to play a role in cell signaling, merozoite egress, phospholipid biosynthesis and, possibly, other biochemical pathways. Here, we review our current knowledge of the ultrastructure of Maurer's clefts, their proteinaceous composition and their function in protein trafficking.
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Affiliation(s)
- Michael Lanzer
- Abteilung Parasitologie, Hygiene-Institut, Universitätsklinikum Heidelberg, Im Neuenheimer Feld 324, D-69120 Heidelberg, Germany.
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Farias SL, Gazarini ML, Melo RL, Hirata IY, Juliano MA, Juliano L, Garcia CRS. Cysteine-protease activity elicited by Ca2+ stimulus in Plasmodium. Mol Biochem Parasitol 2005; 141:71-9. [PMID: 15811528 DOI: 10.1016/j.molbiopara.2005.01.015] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2004] [Revised: 01/11/2005] [Accepted: 01/26/2005] [Indexed: 11/26/2022]
Abstract
Bloodstage malaria parasites require proteolytic activity for key processes as invasion, hemoglobin degradation and merozoite escape from red blood cells (RBCs). We investigated by confocal microscopy the presence of cysteine-protease activity elicited by calcium stimulus in Plasmodium chabaudi and Plasmodium falciparum in free trophozoites or for the later parasite within RBC using fluorescence resonance energy transfer (FRET) peptides. Peptide probes access, to either free or intraerythrocytic parasites, was also tested by selecting a range of fluorescent peptides (653-3146 Da molecular mass) labeled with Abz or FITC. In the present work we show that Ca2+ stimulus elicited by treatment with either melatonin, thapsigargin, ionomicin or nigericin, promotes an increase of substrate hydrolysis, which was blocked by the specific cysteine-protease inhibitor E-64 and the intracellular Ca2+ chelator, BAPTA. When parasites were treated with cytoplasmic Ca2+ releasing compounds, a cysteine-protease was labeled in the parasite cytoplasm by the fluorescent specific irreversible inhibitor, Ethyl-Eps-Leu-Tyr-Cap-Lys(Abz)-NH2, where Ethyl-Eps is Ethyl-(2S,3S)-oxirane-2,3-dicarboxylate. In summary, we demonstrate that P. chabaudi and P. falciparum have a cytoplasmic dependent cysteine-protease activity elicited by Ca2+.
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Affiliation(s)
- Shirley L Farias
- Department of Biophysics, Escola Paulista de Medicina, Universidade Federal de São Paulo, SP, Brazil
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39
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Ginsburg H, Stein WD. How many functional transport pathways does Plasmodium falciparum induce in the membrane of its host erythrocyte? Trends Parasitol 2005; 21:118-21. [PMID: 15734658 DOI: 10.1016/j.pt.2005.01.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Intraerythrocytic malaria parasites induce considerable change in the permeability of the membrane of their host cell. Using classical techniques of radiolabel uptake and iso-osmotic lysis, the permeability characteristics of the host-cell membrane have been determined. In a recent analysis of these results, we concluded that there are at least two types of channel that conform to the data: a low copy number (four channels per cell) type that mediates the transport of cations, anions and most other osmolytes that were tested, and a high copy number (300-400 channels per cell) type that is an anion channel that could also mediate the translocation of purine nucleosides. Patch-clamping experiments using cells infected with Plasmodium falciparum reveal 200-1000 anion channels of more than one type that are of host-cell endogenous provenance. Recent reports show that parasites can grow normally in erythrocytes that lack these endogenous agencies and in which the anion channels are not expressed, although their osmolyte permeability is present. We suggest that only the latter type of channel is important for normal development of the parasite.
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Affiliation(s)
- Hagai Ginsburg
- Department of Biological Chemistry, Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.
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40
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Martin RE, Henry RI, Abbey JL, Clements JD, Kirk K. The 'permeome' of the malaria parasite: an overview of the membrane transport proteins of Plasmodium falciparum. Genome Biol 2005; 6:R26. [PMID: 15774027 PMCID: PMC1088945 DOI: 10.1186/gb-2005-6-3-r26] [Citation(s) in RCA: 129] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2004] [Revised: 12/31/2004] [Accepted: 01/28/2005] [Indexed: 11/24/2022] Open
Abstract
Bioinformatic and expression analyses attribute putative functions to transporters and channels encoded by the Plasmodium falciparum genome. The malaria parasite has substantially more membrane transport proteins than previously thought. Background The uptake of nutrients, expulsion of metabolic wastes and maintenance of ion homeostasis by the intraerythrocytic malaria parasite is mediated by membrane transport proteins. Proteins of this type are also implicated in the phenomenon of antimalarial drug resistance. However, the initial annotation of the genome of the human malaria parasite Plasmodium falciparum identified only a limited number of transporters, and no channels. In this study we have used a combination of bioinformatic approaches to identify and attribute putative functions to transporters and channels encoded by the malaria parasite, as well as comparing expression patterns for a subset of these. Results A computer program that searches a genome database on the basis of the hydropathy plots of the corresponding proteins was used to identify more than 100 transport proteins encoded by P. falciparum. These include all the transporters previously annotated as such, as well as a similar number of candidate transport proteins that had escaped detection. Detailed sequence analysis enabled the assignment of putative substrate specificities and/or transport mechanisms to all those putative transport proteins previously without. The newly-identified transport proteins include candidate transporters for a range of organic and inorganic nutrients (including sugars, amino acids, nucleosides and vitamins), and several putative ion channels. The stage-dependent expression of RNAs for 34 candidate transport proteins of particular interest are compared. Conclusion The malaria parasite possesses substantially more membrane transport proteins than was originally thought, and the analyses presented here provide a range of novel insights into the physiology of this important human pathogen.
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Affiliation(s)
- Rowena E Martin
- School of Biochemistry and Molecular Biology, Faculty of Science, The Australian National University, Canberra, ACT 0200, Australia
| | - Roselani I Henry
- School of Biochemistry and Molecular Biology, Faculty of Science, The Australian National University, Canberra, ACT 0200, Australia
| | - Janice L Abbey
- School of Biochemistry and Molecular Biology, Faculty of Science, The Australian National University, Canberra, ACT 0200, Australia
| | - John D Clements
- School of Biochemistry and Molecular Biology, Faculty of Science, The Australian National University, Canberra, ACT 0200, Australia
- Division of Neuroscience, The John Curtin School of Medical Research, The Australian National University, Canberra, ACT 0200, Australia
| | - Kiaran Kirk
- School of Biochemistry and Molecular Biology, Faculty of Science, The Australian National University, Canberra, ACT 0200, Australia
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Huber SM, Duranton C, Lang F. Patch-clamp analysis of the "new permeability pathways" in malaria-infected erythrocytes. INTERNATIONAL REVIEW OF CYTOLOGY 2005; 246:59-134. [PMID: 16164967 DOI: 10.1016/s0074-7696(05)46003-9] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The intraerythrocytic amplification of the malaria parasite Plasmodium falciparum induces new pathways of solute permeability in the host cell's membrane. These pathways play a pivotal role in parasite development by supplying the parasite with nutrients, disposing of the parasite's metabolic waste and organic osmolytes, and adapting the host's electrolyte composition to the parasite's needs. The "new permeability pathways" allow the fast electrogenic diffusion of ions and thus can be analyzed by patch-clamp single-channel or whole-cell recording. By employing these techniques, several ion-channel types with different electrophysiological profiles have been identified in P. falciparum-infected erythrocytes; they have also been identified in noninfected cells. This review discusses a possible contribution of these channels to the new permeability pathways on the one hand and their supposed functions in noninfected erythrocytes on the other.
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Affiliation(s)
- Stephan M Huber
- Department of Physiology, Eberhard-Karls-University, D-72076 Tübingen, Germany
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Przyborski JM, Lanzer M. Protein transport and trafficking inPlasmodium falciparum-infected erythrocytes. Parasitology 2004; 130:373-88. [PMID: 15830811 DOI: 10.1017/s0031182004006729] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The human malarial parasitePlasmodium falciparumextensively modifies its host erythrocyte, and to this end, is faced with an interesting challenge. It must not only sort proteins to common organelles such as endoplasmic reticulum, Golgi and mitochondria, but also target proteins across the ‘extracellular’ cytosol of its host cell. Furthermore, as a member of the phylum Apicomplexa, the parasite has to sort proteins to novel organelles such as the apicoplast, micronemes and rhoptries. In order to overcome these difficulties, the parasite has created a novel secretory system, which has been characterized in ever-increasing detail in the past decade. Along with the ‘hardware’ for a secretory system, the parasite also needs to ‘program’ proteins to enable high fidelity sorting to their correct subcellular location. The nature of these sorting signals has remained until relatively recently, enigmatic. Experimental work has now begun to dissect the sorting signals responsible for correct subcellular targeting of parasite-encoded proteins. In this review we summarize the current understanding of such signals, and comment on their role in protein sorting in this organism, which may become a model for the study of novel protein trafficking mechanisms.
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Affiliation(s)
- J M Przyborski
- Hygiene Institute, Department of Parasitology, University of Heidelberg, Im Neuenheimer Feld 324, D-69120 Heidelberg, Germany
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Ellekvist P, Ricke CH, Litman T, Salanti A, Colding H, Zeuthen T, Klaerke DA. Molecular cloning of a K+ channel from the malaria parasite Plasmodium falciparum. Biochem Biophys Res Commun 2004; 318:477-84. [PMID: 15120625 DOI: 10.1016/j.bbrc.2004.04.049] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2004] [Indexed: 11/29/2022]
Abstract
In most living cells, K(+) channels are important for the generation of the membrane potential and for volume regulation. The parasite Plasmodium falciparum, which causes malignant malaria, must be able to deal with large variations in the ambient K(+) concentration: it is exposed to high concentrations of K(+) when inside the erythrocyte and low concentrations when in plasma. In the recently published genome of P. falciparum, we have identified a gene, pfkch1, encoding a potential K(+) channel, which to some extent resembles the big-conductance (BK) K(+) channel. We have cloned the approximately 6000 nucleotide (nt) fragment from cDNA, studied the pattern of expression of pfkch1 throughout the intraerythrocytic part of the parasite's life-cyclus, and characterized the channel on the basis of similarity to other K(+) channels from pro- and eukaryotic organisms. This P. falciparum K(+) channel could be a potential drug target.
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Affiliation(s)
- Peter Ellekvist
- Department of Medical Physiology, University of Copenhagen, Denmark.
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