1
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Won JY, Mazigo E, Cha SH, Han JH. Functional characterization of Plasmodium vivax hexose transporter 1. Front Cell Infect Microbiol 2024; 13:1321240. [PMID: 38282613 PMCID: PMC10811246 DOI: 10.3389/fcimb.2023.1321240] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Accepted: 12/27/2023] [Indexed: 01/30/2024] Open
Abstract
Plasmodium vivax is the most widely distributed human malaria parasite. The eradication of vivax malaria remains challenging due to transmission of drug-resistant parasite and dormant liver form. Consequently, anti-malarial drugs with novel mechanisms of action are urgently demanded. Glucose uptake blocking strategy is suggested as a novel mode of action that leads to selective starvation in various species of malaria parasites. The role of hexose transporter 1 in Plasmodium species is glucose uptake, and its blocking strategies proved to successfully induce selective starvation. However, there is limited information on the glucose uptake properties via P. vivax hexose transporter 1 (PvHT1). Thus, we focused on the PvHT1 to precisely identify its properties of glucose uptake. The PvHT1 North Korean strain (PvHT1NK) expressed Xenopus laevis oocytes mediating the transport of [3H] deoxy-D-glucose (ddGlu) in an expression and incubation time-dependent manner without sodium dependency. Moreover, the PvHT1NK showed no exchange mode of glucose in efflux experiments and concentration-dependent results showed saturable kinetics following the Michaelis-Menten equation. Non-linear regression analysis revealed a Km value of 294.1 μM and a Vmax value of 1,060 pmol/oocyte/hr, and inhibition experiments showed a strong inhibitory effect by glucose, mannose, and ddGlu. Additionally, weak inhibition was observed with fructose and galactose. Comparison of amino acid sequence and tertiary structure between P. falciparum and P. vivax HT1 revealed a completely conserved residue in glucose binding pocket. This result supported that the glucose uptake properties are similar to P. falciparum, and PfHT1 inhibitor (compound 3361) works in P. vivax. These findings provide properties of glucose uptake via PvHT1NK for carbohydrate metabolism and support the approaches to vivax malaria drug development strategy targeting the PvHT1 for starving of the parasite.
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Affiliation(s)
- Jeong Yeon Won
- Department of Parasitology and Tropical Medicine, School of Medicine, Inha University, Incheon, Republic of Korea
| | - Ernest Mazigo
- Department of Medical Environmental Biology and Tropical Medicine, School of Medicine, Kangwon National University, Chuncheon, Republic of Korea
| | - Seok Ho Cha
- Department of Parasitology and Tropical Medicine, School of Medicine, Inha University, Incheon, Republic of Korea
| | - Jin-Hee Han
- Department of Medical Environmental Biology and Tropical Medicine, School of Medicine, Kangwon National University, Chuncheon, Republic of Korea
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2
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Pradhan D, Biswasroy P, Kulkarni S, Taliyan R, Pradhan DK, Bhola RK, Mahapatra S, Ghosh G, Rath G. Identification of starvation-mimetic bioactive phytocomponent from Withania somnifera using in-silico molecular modelling and flow cytometry-based analysis for the management of malaria. J Biomol Struct Dyn 2024; 42:528-549. [PMID: 37087726 DOI: 10.1080/07391102.2023.2201855] [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: 02/15/2023] [Accepted: 03/15/2023] [Indexed: 04/24/2023]
Abstract
Multidrug resistance episodes in malaria increased from 3.9% to 20% from 2015 to 2019. Synchronizing the clinical manifestation in chronological sequence led to a unique impression on glucose demand (increased up to 100-fold) by the parasite-infected RBCs. Hence, restriction in the glucose uptake to parasite-infected RBCs could be an alternative approach to conquer the global burden of malaria to a greater extent. A C28 steroidal lactone Withaferin A (WS-3) isolated from Withania somnifera leave extract shows better thermodynamically stable interactions with the glucose transporters (GLUT-1 and PfHT) to standard drugs metformin and lopinavir. MD simulations for a trajectory period of 100 ns reflect stable interactions with the interactive amino acid residues such as Pro141, Gln161, Gln282, Gln283, Trp388, Phe389, and Phe40, Asn48, Phe85, His168, Gln169, Asn311 which potentiating inhibitory activity of WS-3 against GLUT-1 and PfHT respectively. WS-3 was non-hemotoxic (%hemolysis <5%) for a high concentration of up to 1 mg/ml in the physiological milieu. However, the %hemolysis significantly increased up to 30.55 ± 0.929% in a parasitophorous simulated environment (pH 5.0). Increased hemolysis of WS-3 could be due to the production of ROS in an acidic environment. Further, the inhibitory activity of WS-3 against both glucose transporters was supported with flow cytometry-based analysis of parasite-infected RBCs. Results show that WS-3 has low mean fluorescence intensities for both target proteins compared to conventional drugs, suggesting a potential sugar transporter inhibitor against GLUT-1 and PfHT for managing malaria. Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Deepak Pradhan
- Department of Herbal Nanotechnology, School of Pharmaceutical Sciences, Siksha O Anusandhan (Deemed to be University), Bhubaneswar, Odisha, India
- R and D Division, Ixoreal Biomed. Pvt. Ltd, Hyderabad, Telangana, India
| | - Prativa Biswasroy
- Department of Herbal Nanotechnology, School of Pharmaceutical Sciences, Siksha O Anusandhan (Deemed to be University), Bhubaneswar, Odisha, India
| | | | - Rajiv Taliyan
- Department of Pharmacy, BITS Pilani, Pilani, Rajasthan, India
| | - Dilip Kumar Pradhan
- Department of Medicine, Pandit Raghunath Murmu Medical College & Hospital, Baripada, Odisha, India
| | - Rajesh Kumar Bhola
- Department of Hematology, Institute of Medical Sciences and Sum Hospital, Siksha O Anusandhan (Deemed to be University), Bhubaneswar, Odisha, India
| | - Sonali Mahapatra
- Department of Biological Systems Engineering, University of Wisconsin-Madison, Madison, WI, USA
| | - Goutam Ghosh
- Department of Herbal Nanotechnology, School of Pharmaceutical Sciences, Siksha O Anusandhan (Deemed to be University), Bhubaneswar, Odisha, India
| | - Goutam Rath
- Department of Herbal Nanotechnology, School of Pharmaceutical Sciences, Siksha O Anusandhan (Deemed to be University), Bhubaneswar, Odisha, India
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3
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Henshall IG, Spielmann T. Critical interdependencies between Plasmodium nutrient flux and drugs. Trends Parasitol 2023; 39:936-944. [PMID: 37716852 PMCID: PMC10580322 DOI: 10.1016/j.pt.2023.08.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Revised: 08/23/2023] [Accepted: 08/24/2023] [Indexed: 09/18/2023]
Abstract
Nutrient import and waste efflux are critical dependencies for intracellular Plasmodium falciparum parasites. Nutrient transport proteins are often lineage specific and can provide unique targets for antimalarial drug development. P. falciparum nutrient transport pathways can be a double-edged sword for the parasite, not only mediating the import of nutrients and excretion of waste products but also providing an access route for drugs. Here we briefly summarise the nutrient acquisition pathways of intracellular P. falciparum blood-stage parasites and then highlight how these pathways influence many aspects relevant to antimalarial drugs, resulting in complex and often underappreciated interdependencies.
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Affiliation(s)
| | - Tobias Spielmann
- Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany.
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4
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Suades A, Qureshi A, McComas SE, Coinçon M, Rudling A, Chatzikyriakidou Y, Landreh M, Carlsson J, Drew D. Establishing mammalian GLUT kinetics and lipid composition influences in a reconstituted-liposome system. Nat Commun 2023; 14:4070. [PMID: 37429918 DOI: 10.1038/s41467-023-39711-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Accepted: 06/26/2023] [Indexed: 07/12/2023] Open
Abstract
Glucose transporters (GLUTs) are essential for organism-wide glucose homeostasis in mammals, and their dysfunction is associated with numerous diseases, such as diabetes and cancer. Despite structural advances, transport assays using purified GLUTs have proven to be difficult to implement, hampering deeper mechanistic insights. Here, we have optimized a transport assay in liposomes for the fructose-specific isoform GLUT5. By combining lipidomic analysis with native MS and thermal-shift assays, we replicate the GLUT5 transport activities seen in crude lipids using a small number of synthetic lipids. We conclude that GLUT5 is only active under a specific range of membrane fluidity, and that human GLUT1-4 prefers a similar lipid composition to GLUT5. Although GLUT3 is designated as the high-affinity glucose transporter, in vitro D-glucose kinetics demonstrates that GLUT1 and GLUT3 actually have a similar KM, but GLUT3 has a higher turnover. Interestingly, GLUT4 has a high KM for D-glucose and yet a very slow turnover, which may have evolved to ensure uptake regulation by insulin-dependent trafficking. Overall, we outline a much-needed transport assay for measuring GLUT kinetics and our analysis implies that high-levels of free fatty acid in membranes, as found in those suffering from metabolic disorders, could directly impair glucose uptake.
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Affiliation(s)
- Albert Suades
- Department of Biochemistry and Biophysics, Stockholm University, Svante Arrhenius v. 16c, SE-106 91, Stockholm, Sweden
| | - Aziz Qureshi
- Department of Biochemistry and Biophysics, Stockholm University, Svante Arrhenius v. 16c, SE-106 91, Stockholm, Sweden
| | - Sarah E McComas
- Department of Biochemistry and Biophysics, Stockholm University, Svante Arrhenius v. 16c, SE-106 91, Stockholm, Sweden
| | - Mathieu Coinçon
- Department of Biochemistry and Biophysics, Stockholm University, Svante Arrhenius v. 16c, SE-106 91, Stockholm, Sweden
| | - Axel Rudling
- Science for Life Laboratory, Department of Cell and Molecular Biology, Uppsala University, BMC, Box 596, SE-751 24, Uppsala, Sweden
| | - Yurie Chatzikyriakidou
- Department of Biochemistry and Biophysics, Stockholm University, Svante Arrhenius v. 16c, SE-106 91, Stockholm, Sweden
| | - Michael Landreh
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Solnavägen 9, SE-171 65, Solna, Sweden
| | - Jens Carlsson
- Science for Life Laboratory, Department of Cell and Molecular Biology, Uppsala University, BMC, Box 596, SE-751 24, Uppsala, Sweden
| | - David Drew
- Department of Biochemistry and Biophysics, Stockholm University, Svante Arrhenius v. 16c, SE-106 91, Stockholm, Sweden.
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Altharawi A, Riadi Y, Tahir Ul Qamar M. An in silico quest for next-generation antimalarial drugs by targeting Plasmodium falciparum hexose transporter protein: a multi-pronged approach. J Biomol Struct Dyn 2023; 41:14450-14459. [PMID: 36812293 DOI: 10.1080/07391102.2023.2181635] [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: 12/19/2022] [Accepted: 02/12/2023] [Indexed: 02/24/2023]
Abstract
The emergence of artemisinin resistance by malaria parasites is a major challenge in the fight against malaria, thus posing serious threat to the public health across the world. To tackle this, antimalarial drugs with unconventional mechanisms are therefore urgently needed. It has been reported that selective starvation of Plasmodium falciparum by blocking the function of hexose transporter 1 (PfHT1) protein, the only known transporter for glucose uptake in P. falciparum, could provide an alternative approach to fight the drug resistant malaria parasites. In this study, three high affinity molecules (BBB_25784317, BBB_26580136 and BBB_26580144) that have shown the best docked conformation and least binding energy with PfHT1 were shortlisted. The docking energy of BBB_25784317, BBB_26580136 and BBB_26580144 with PfHT1 were -12.5, -12.1 and -12.0 kcal/mol, respectively. In the follow up simulation studies, the protein 3D structure maintains considerable stability in the presence of the compounds. It was also observed that the compounds produced a number of hydrophilic and hydrophobic interactions with the protein allosteric site residues. This demonstrates strong intermolecular interaction guided by close distance hydrogen bonds of compounds with Ser45, Asn48, Thr49, Asn52, Ser317, Asn318, Ile330 and Ser334. Revalidation of compounds binding affinity was conducted by more appropriate simulation based binding free energy techniques (MM-GB/PBSA and WaterSwap). Additionally, entropy assay was performed that further strengthen the predictions. In silico pharmacokinetics confirmed that the compounds would be suitable candidates for oral delivery due to their high gastrointestinal absorption and less toxic reaction. Overall, the predicted compounds are promising and could be further sought as antimalarial leads and subjected to thorough experimental investigations.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Ali Altharawi
- Department of Pharmaceutical Chemistry, College of Pharmacy, Prince Sattam Bin Abdulaziz University, Al-Kharj, Saudi Arabia
| | - Yassine Riadi
- Department of Pharmaceutical Chemistry, College of Pharmacy, Prince Sattam Bin Abdulaziz University, Al-Kharj, Saudi Arabia
| | - Muhammad Tahir Ul Qamar
- Department of Bioinformatics and Biotechnology, Government College University Faisalabad (GCUF), Faisalabad, Pakistan
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6
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Krombauer GC, Guedes KDS, Banfi FF, Nunes RR, Fonseca ALD, Siqueira EPD, Bellei JCB, Scopel KKG, Varotti FDP, Sanchez BAM. In vitro and in silico assessment of new beta amino ketones with antiplasmodial activity. Rev Soc Bras Med Trop 2022; 55:e0590. [PMID: 36169491 PMCID: PMC9549944 DOI: 10.1590/0037-8682-0590-2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Accepted: 06/24/2022] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND Based on the current need for new drugs against malaria, our study evaluated eight beta amino ketones in silico and in vitro for potential antimalarial activity. METHODS Using the Brazilian Malaria Molecular Targets (BraMMT) and OCTOPUS® software programs, the pattern of interactions of beta-amino ketones was described against different proteins of P. falciparum and screened to evaluate their physicochemical properties. The in vitro antiplasmodial activities of the compounds were evaluated using a SYBR Green-based assay. In parallel, in vitro cytotoxic data were obtained using the MTT assay. RESULTS Among the eight compounds, compound 1 was the most active and selective against P. falciparum (IC50 = 0.98 µM; SI > 60). Six targets were identified in BraMMT that interact with compounds exhibiting a stronger binding energy than the crystallographic ligand: P. falciparum triophosphate phosphoglycolate complex (1LYX), P. falciparum reductase (2OK8), PfPK7 (2PML), P. falciparum glutaredoxin (4N0Z), PfATP6, and PfHT. CONCLUSIONS The physicochemical properties of compound 1 were compatible with the set of criteria established by the Lipinski rule and demonstrated its potential as a drug prototype for antiplasmodial activity.
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Affiliation(s)
- Gabriela Camila Krombauer
- Universidade Federal de Mato Grosso, Núcleo de Pesquisa e Apoio Didático em Saúde, Laboratório de Imunopatologia e Doenças Tropicais, Sinop, MT, Brasil
| | - Karla de Sena Guedes
- Universidade Federal de Mato Grosso, Núcleo de Pesquisa e Apoio Didático em Saúde, Laboratório de Imunopatologia e Doenças Tropicais, Sinop, MT, Brasil
| | - Felipe Fingir Banfi
- Universidade Federal de Mato Grosso, Núcleo de Pesquisa e Apoio Didático em Saúde, Laboratório de Imunopatologia e Doenças Tropicais, Sinop, MT, Brasil
| | - Renata Rachide Nunes
- Universidade Federal de São João Del Rei, Campus Centro Oeste, Núcleo de Pesquisa em Química Biológica (NQBio), Divinópolis, MG, Brasil
| | - Amanda Luisa da Fonseca
- Universidade Federal de São João Del Rei, Campus Centro Oeste, Núcleo de Pesquisa em Química Biológica (NQBio), Divinópolis, MG, Brasil
| | | | - Jéssica Côrrea Bezerra Bellei
- Universidade Federal de Juiz de Fora, Centro de Pesquisas em Parasitologia, Departamento de Parasitologia, Microbiologia e Imunologia, Juiz de Fora, MG, Brasil
| | - Kézia Katiani Gorza Scopel
- Universidade Federal de Juiz de Fora, Centro de Pesquisas em Parasitologia, Departamento de Parasitologia, Microbiologia e Imunologia, Juiz de Fora, MG, Brasil
| | - Fernando de Pilla Varotti
- Universidade Federal de São João Del Rei, Campus Centro Oeste, Núcleo de Pesquisa em Química Biológica (NQBio), Divinópolis, MG, Brasil
| | - Bruno Antônio Marinho Sanchez
- Universidade Federal de Mato Grosso, Núcleo de Pesquisa e Apoio Didático em Saúde, Laboratório de Imunopatologia e Doenças Tropicais, Sinop, MT, Brasil
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7
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Jiang X. An overview of the Plasmodium falciparum hexose transporter and its therapeutic interventions. Proteins 2022; 90:1766-1778. [PMID: 35445447 PMCID: PMC9790349 DOI: 10.1002/prot.26351] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Revised: 02/22/2022] [Accepted: 03/30/2022] [Indexed: 12/30/2022]
Abstract
Despite intense elimination efforts, human malaria, caused by the infection of five Plasmodium species, remains the deadliest parasitic disease in the world. Even worse, with the emergence and spreading of the first-line drug-resistant Plasmodium parasites, therapeutic interventions based on novel plasmodial drug targets are more necessary than ever. Given that the blood-stage parasites primarily rely on glycolysis for their energy supply, blocking glucose uptake, the rate-limiting step of ATP generation, was considered a promising approach to kill these parasites. To achieve this goal, characterization of the plasmodial hexose transporter and development of selective inhibitors have been pursued for decades. Here, we review the identification and characterization of the Plasmodium falciparum hexose transporter (PfHT1) and summarize current advances in its inhibitor development.
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Affiliation(s)
- Xin Jiang
- School of Biotechnology and Biomolecular Sciencesthe University of New South WalesSydneyNew South Wales
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8
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Lv L, Xu Z, Zhao M, Gao J, Jiang R, Wang Q, Shi X. Mannose inhibits Plasmodium parasite growth and cerebral malaria development via regulation of host immune responses. Front Immunol 2022; 13:859228. [PMID: 36211381 PMCID: PMC9546034 DOI: 10.3389/fimmu.2022.859228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Accepted: 09/08/2022] [Indexed: 11/16/2022] Open
Abstract
D-mannose can be transported into a variety of cells via glucose transporter (GLUT), and supraphysiological levels of D-mannose impairs tumor growth and modulates immune cell function through mechanisms such as interference with glycolysis and induction of oxidative stress. Blood-stage Plasmodium mainly depends on glycolysis for energy supply and pathological immune response plays a vital role in cerebral malaria. However, it is not clear whether mannose affects malaria blood-stage infection. Here, we fed D-mannose to Plasmodium berghei-infected mice and found weight loss and reduced parasitemia without apparent side effects. Compromised parasitemia in C57BL/6 mice was accompanied by an increase in splenic macrophages compared to an untreated group. When mannose was applied to a rodent experimental cerebral malaria (ECM) model, the incidence of ECM decreased. Expression of activation marker CD69 on T cells in peripheral blood and the brain were reduced, and cerebral migration of activated T cells was prevented by decreased expression of CXCR3. These findings suggest that mannose inhibits Plasmodium infection by regulating multiple host immune responses and could serve as a potential strategy for facilitating malaria treatment.
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Affiliation(s)
- Li Lv
- Department of Endocrinology and Metabolism, Tianjin Medical University General Hospital, Tianjin, China
| | - Zihao Xu
- Department of Immunology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin Key Laboratory of Cellular and Molecular Immunology, Key Laboratory of Immune Microenvironment and Diseases of Educational Ministry of China, Tianjin, China
| | - Meichen Zhao
- Department of Immunology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin Key Laboratory of Cellular and Molecular Immunology, Key Laboratory of Immune Microenvironment and Diseases of Educational Ministry of China, Tianjin, China
| | - Jian Gao
- Department of Immunology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin Key Laboratory of Cellular and Molecular Immunology, Key Laboratory of Immune Microenvironment and Diseases of Educational Ministry of China, Tianjin, China
| | - Rumeng Jiang
- Department of Immunology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin Key Laboratory of Cellular and Molecular Immunology, Key Laboratory of Immune Microenvironment and Diseases of Educational Ministry of China, Tianjin, China
| | - Qian Wang
- Department of Immunology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin Key Laboratory of Cellular and Molecular Immunology, Key Laboratory of Immune Microenvironment and Diseases of Educational Ministry of China, Tianjin, China
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
- *Correspondence: Qian Wang, ; Xiaoyu Shi,
| | - Xiaoyu Shi
- Department of Immunology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin Key Laboratory of Cellular and Molecular Immunology, Key Laboratory of Immune Microenvironment and Diseases of Educational Ministry of China, Tianjin, China
- *Correspondence: Qian Wang, ; Xiaoyu Shi,
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9
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Monteiro Júnior JC, Krüger A, Palmisano G, Wrenger C. Transporter-Mediated Solutes Uptake as Drug Target in Plasmodium falciparum. Front Pharmacol 2022; 13:845841. [PMID: 35370717 PMCID: PMC8965513 DOI: 10.3389/fphar.2022.845841] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Accepted: 02/09/2022] [Indexed: 02/05/2023] Open
Abstract
Malaria remains a public health problem with still more than half a million deaths annually. Despite ongoing efforts of many countries, malaria elimination has been difficult due to emerging resistances against most traditional drugs, including artemisinin compounds - the most potent antimalarials currently available. Therefore, the discovery and development of new drugs with novel mechanisms of action to circumvent resistances is urgently needed. In this sense, one of the most promising areas is the exploration of transport proteins. Transporters mediate solute uptake for intracellular parasite proliferation and survival. Targeting transporters can exploit these processes to eliminate the parasite. Here, we focus on transporters of the Plasmodium falciparum-infected red blood cell studied as potential biological targets and discuss published drugs directed at them.
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Affiliation(s)
- Júlio César Monteiro Júnior
- Unit for Drug Discovery, Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Arne Krüger
- Unit for Drug Discovery, Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Giuseppe Palmisano
- GlycoProteomics Laboratory, Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Carsten Wrenger
- Unit for Drug Discovery, Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
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An Uninvited Seat at the Dinner Table: How Apicomplexan Parasites Scavenge Nutrients from the Host. Microorganisms 2021; 9:microorganisms9122592. [PMID: 34946193 PMCID: PMC8707601 DOI: 10.3390/microorganisms9122592] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Revised: 12/10/2021] [Accepted: 12/13/2021] [Indexed: 12/24/2022] Open
Abstract
Obligate intracellular parasites have evolved a remarkable assortment of strategies to scavenge nutrients from the host cells they parasitize. Most apicomplexans form a parasitophorous vacuole (PV) within the invaded cell, a replicative niche within which they survive and multiply. As well as providing a physical barrier against host cell defense mechanisms, the PV membrane (PVM) is also an important site of nutrient uptake that is essential for the parasites to sustain their metabolism. This means nutrients in the extracellular milieu are separated from parasite metabolic machinery by three different membranes, the host plasma membrane, the PVM, and the parasite plasma membrane (PPM). In order to facilitate nutrient transport from the extracellular environment into the parasite itself, transporters on the host cell membrane of invaded cells can be modified by secreted and exported parasite proteins to maximize uptake of key substrates to meet their metabolic demand. To overcome the second barrier, the PVM, apicomplexan parasites secrete proteins contained in the dense granules that remodel the vacuole and make the membrane permissive to important nutrients. This bulk flow of host nutrients is followed by a more selective uptake of substrates at the PPM that is operated by specific transporters of this third barrier. In this review, we recapitulate and compare the strategies developed by Apicomplexa to scavenge nutrients from their hosts, with particular emphasis on transporters at the parasite plasma membrane and vacuolar solute transporters on the parasite intracellular digestive organelle.
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Mesén-Ramírez P, Bergmann B, Elhabiri M, Zhu L, von Thien H, Castro-Peña C, Gilberger TW, Davioud-Charvet E, Bozdech Z, Bachmann A, Spielmann T. The parasitophorous vacuole nutrient channel is critical for drug access in malaria parasites and modulates the artemisinin resistance fitness cost. Cell Host Microbe 2021; 29:1774-1787.e9. [PMID: 34863371 DOI: 10.1016/j.chom.2021.11.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Revised: 09/14/2021] [Accepted: 11/03/2021] [Indexed: 02/08/2023]
Abstract
Intraerythrocytic malaria parasites proliferate bounded by a parasitophorous vacuolar membrane (PVM). The PVM contains nutrient permeable channels (NPCs) conductive to small molecules, but their relevance for parasite growth for individual metabolites is largely untested. Here we show that growth-relevant levels of major carbon and energy sources pass through the NPCs. Moreover, we find that NPCs are a gate for several antimalarial drugs, highlighting their permeability properties as a critical factor for drug design. Looking into NPC-dependent amino acid transport, we find that amino acid shortage is a reason for the fitness cost in artemisinin-resistant (ARTR) parasites and provide evidence that NPC upregulation to increase amino acids acquisition is a mechanism of ARTR parasites in vitro and in human infections to compensate this fitness cost. Hence, the NPCs are important for nutrient and drug access and reveal amino acid deprivation as a critical constraint in ARTR parasites.
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Affiliation(s)
- Paolo Mesén-Ramírez
- Bernhard Nocht Institute for Tropical Medicine, Bernhard Nocht Str. 74, 20359 Hamburg, Germany
| | - Bärbel Bergmann
- Bernhard Nocht Institute for Tropical Medicine, Bernhard Nocht Str. 74, 20359 Hamburg, Germany
| | - Mourad Elhabiri
- UMR7042 Université de Strasbourg‒CNRS‒UHA, Laboratoire d'Innovation Moléculaire et Applications (LIMA), Team Bio(IN)organic and Medicinal Chemistry, European School of Chemistry, Polymers and Materials (ECPM), 25 Rue Becquerel, F-67087 Strasbourg, France
| | - Lei Zhu
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Singapore
| | - Heidrun von Thien
- Bernhard Nocht Institute for Tropical Medicine, Bernhard Nocht Str. 74, 20359 Hamburg, Germany; Centre for Structural Systems Biology, Notkestraße 85, Building 15, 22607, University of Hamburg, 20146 Hamburg, Germany
| | - Carolina Castro-Peña
- Bernhard Nocht Institute for Tropical Medicine, Bernhard Nocht Str. 74, 20359 Hamburg, Germany
| | - Tim-Wolf Gilberger
- Bernhard Nocht Institute for Tropical Medicine, Bernhard Nocht Str. 74, 20359 Hamburg, Germany; Centre for Structural Systems Biology, Notkestraße 85, Building 15, 22607, University of Hamburg, 20146 Hamburg, Germany
| | - Elisabeth Davioud-Charvet
- UMR7042 Université de Strasbourg‒CNRS‒UHA, Laboratoire d'Innovation Moléculaire et Applications (LIMA), Team Bio(IN)organic and Medicinal Chemistry, European School of Chemistry, Polymers and Materials (ECPM), 25 Rue Becquerel, F-67087 Strasbourg, France
| | - Zbynek Bozdech
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Singapore; Honorary Visiting Research Fellow, Nuffield Department of Medicine, University of Oxford, UK
| | - Anna Bachmann
- Bernhard Nocht Institute for Tropical Medicine, Bernhard Nocht Str. 74, 20359 Hamburg, Germany; Centre for Structural Systems Biology, Notkestraße 85, Building 15, 22607, University of Hamburg, 20146 Hamburg, Germany
| | - Tobias Spielmann
- Bernhard Nocht Institute for Tropical Medicine, Bernhard Nocht Str. 74, 20359 Hamburg, Germany.
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12
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Drew D, North RA, Nagarathinam K, Tanabe M. Structures and General Transport Mechanisms by the Major Facilitator Superfamily (MFS). Chem Rev 2021; 121:5289-5335. [PMID: 33886296 PMCID: PMC8154325 DOI: 10.1021/acs.chemrev.0c00983] [Citation(s) in RCA: 165] [Impact Index Per Article: 55.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Indexed: 12/12/2022]
Abstract
The major facilitator superfamily (MFS) is the largest known superfamily of secondary active transporters. MFS transporters are responsible for transporting a broad spectrum of substrates, either down their concentration gradient or uphill using the energy stored in the electrochemical gradients. Over the last 10 years, more than a hundred different MFS transporter structures covering close to 40 members have provided an atomic framework for piecing together the molecular basis of their transport cycles. Here, we summarize the remarkable promiscuity of MFS members in terms of substrate recognition and proton coupling as well as the intricate gating mechanisms undergone in achieving substrate translocation. We outline studies that show how residues far from the substrate binding site can be just as important for fine-tuning substrate recognition and specificity as those residues directly coordinating the substrate, and how a number of MFS transporters have evolved to form unique complexes with chaperone and signaling functions. Through a deeper mechanistic description of glucose (GLUT) transporters and multidrug resistance (MDR) antiporters, we outline novel refinements to the rocker-switch alternating-access model, such as a latch mechanism for proton-coupled monosaccharide transport. We emphasize that a full understanding of transport requires an elucidation of MFS transporter dynamics, energy landscapes, and the determination of how rate transitions are modulated by lipids.
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Affiliation(s)
- David Drew
- Department
of Biochemistry and Biophysics, Stockholm
University, SE 106 91 Stockholm, Sweden
| | - Rachel A. North
- Department
of Biochemistry and Biophysics, Stockholm
University, SE 106 91 Stockholm, Sweden
| | - Kumar Nagarathinam
- Center
of Structural and Cell Biology in Medicine, Institute of Biochemistry, University of Lübeck, D-23538, Lübeck, Germany
| | - Mikio Tanabe
- Structural
Biology Research Center, Institute of Materials Structure Science, High Energy Accelerator Research Organization (KEK), Oho 1-1, Tsukuba, Ibaraki 305-0801, Japan
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13
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Shi X, Wei M, Xu Z, Liu Y, Zhang M, Lv L, Wang Q. Vitamin C Inhibits Blood-Stage Plasmodium Parasites via Oxidative Stress. Front Cell Dev Biol 2021; 9:639944. [PMID: 34046404 PMCID: PMC8144511 DOI: 10.3389/fcell.2021.639944] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Accepted: 04/01/2021] [Indexed: 11/29/2022] Open
Abstract
During the Plasmodium erythrocytic cycle, glucose is taken up by glucose transporters (GLUTs) in red blood cells (RBCs) and supplied to parasites via the Plasmodium hexose transporter. Here, we demonstrate that the glucose uptake pathway in infected RBCs (iRBCs) can be hijacked by vitamin C (Vc). GLUTs preferentially transport the oxidized form of Vc, which is subsequently reduced in the cytosol. Vc, which is expected to burden the intracellular reducing capacity, inhibits Plasmodium berghei and Plasmodium falciparum growth. Vc uptake is drastically increased in iRBCs, with a large proportion entering parasites. Increased absorption of Vc causes accumulation of reactive oxygen species, reduced ATP production, and elevated eryptosis in iRBCs and apoptosis in parasites. The level of oxidative stress induced by Vc is significantly higher in iRBCs than uninfected RBCs, not seen in chloroquine or artemisinin-treated iRBCs, and effective in inhibiting chloroquine or artemisinin-resistant parasites. These findings provide important insights into the drug sensitivity of Plasmodium.
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Affiliation(s)
- Xiaoyu Shi
- Department of Immunology, School of Basic Medical Sciences, Key Laboratory of Immune Microenvironment and Diseases of Educational Ministry of China, Tianjin Key Laboratory of Cellular and Molecular Immunology, Tianjin Medical University, Tianjin, China
| | - Meng Wei
- Department of Immunology, School of Basic Medical Sciences, Key Laboratory of Immune Microenvironment and Diseases of Educational Ministry of China, Tianjin Key Laboratory of Cellular and Molecular Immunology, Tianjin Medical University, Tianjin, China
| | - Zihao Xu
- Department of Immunology, School of Basic Medical Sciences, Key Laboratory of Immune Microenvironment and Diseases of Educational Ministry of China, Tianjin Key Laboratory of Cellular and Molecular Immunology, Tianjin Medical University, Tianjin, China
| | - Ying Liu
- Department of Immunology, School of Basic Medical Sciences, Key Laboratory of Immune Microenvironment and Diseases of Educational Ministry of China, Tianjin Key Laboratory of Cellular and Molecular Immunology, Tianjin Medical University, Tianjin, China
| | - Mujia Zhang
- Department of Immunology, School of Basic Medical Sciences, Key Laboratory of Immune Microenvironment and Diseases of Educational Ministry of China, Tianjin Key Laboratory of Cellular and Molecular Immunology, Tianjin Medical University, Tianjin, China
| | - Li Lv
- Department of Endocrinology and Metabolism, Tianjin Medical University General Hospital, Tianjin, China
| | - Qian Wang
- Department of Immunology, School of Basic Medical Sciences, Key Laboratory of Immune Microenvironment and Diseases of Educational Ministry of China, Tianjin Key Laboratory of Cellular and Molecular Immunology, Tianjin Medical University, Tianjin, China.,National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
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14
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Banfi FF, Krombauer GC, da Fonseca AL, Nunes RR, Andrade SN, de Rezende MA, Chaves MH, Monção EDS, Taranto AG, Rodrigues DDJ, Vieira GM, de Castro WV, Varotti FDP, Sanchez BAM. Dehydrobufotenin extracted from the Amazonian toad Rhinella marina (Anura: Bufonidae) as a prototype molecule for the development of antiplasmodial drugs. J Venom Anim Toxins Incl Trop Dis 2021; 27:e20200073. [PMID: 33519927 PMCID: PMC7812938 DOI: 10.1590/1678-9199-jvatitd-2020-0073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Accepted: 10/28/2020] [Indexed: 11/22/2022] Open
Abstract
Background: The resistance against antimalarial drugs represents a global challenge in the fight and control of malaria. The Brazilian biodiversity can be an important tool for research and development of new medicinal products. In this context, toxinology is a multidisciplinary approach on the development of new drugs, including the isolation, purification, and evaluation of the pharmacological activities of natural toxins. The present study aimed to evaluate the cytotoxicity, as well as the antimalarial activity in silico and in vitro of four compounds isolated from Rhinella marina venom as potential oral drug prototypes. Methods: Four compounds were challenged against 35 target proteins from P. falciparum and screened to evaluate their physicochemical properties using docking assay in Brazilian Malaria Molecular Targets (BraMMT) software and in silico assay in OCTOPUS® software. The in vitro antimalarial activity of the compounds against the 3D7 Plasmodium falciparum clones were assessed using the SYBR Green I based assay (IC50). For the cytotoxic tests, the LD50 was determined in human pulmonary fibroblast cell line using the [3(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] (MTT) assay. Results: All compounds presented a ligand-receptor interaction with ten Plasmodium falciparum-related protein targets, as well as antimalarial activity against chloroquine resistant strain (IC50 = 3.44 μM to 19.11 μM). Three of them (dehydrobufotenine, marinobufagin, and bufalin) showed adequate conditions for oral drug prototypes, with satisfactory prediction of absorption, permeability, and absence of toxicity. In the cell viability assay, only dehydrobufotenin was selective for the parasite. Conclusions: Dehydrobufotenin revealed to be a potential oral drug prototype presenting adequate antimalarial activity and absence of cytotoxicity, therefore should be subjected to further studies.
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Affiliation(s)
- Felipe Finger Banfi
- Laboratory of Immunopathology and Tropical Diseases, Health Education and Research Center (NUPADS), Institute of Health Sciences, Federal University of Mato Grosso, Sinop, MT, Brazil
| | - Gabriela Camila Krombauer
- Laboratory of Immunopathology and Tropical Diseases, Health Education and Research Center (NUPADS), Institute of Health Sciences, Federal University of Mato Grosso, Sinop, MT, Brazil
| | - Amanda Luisa da Fonseca
- Research Center on Biological Chemistry (NQBio), Federal University of São João Del Rei, Divinópolis, MG, Brazil
| | - Renata Rachide Nunes
- Research Center on Biological Chemistry (NQBio), Federal University of São João Del Rei, Divinópolis, MG, Brazil
| | - Silmara Nunes Andrade
- Research Center on Biological Chemistry (NQBio), Federal University of São João Del Rei, Divinópolis, MG, Brazil
| | - Millena Alves de Rezende
- Research Center on Biological Chemistry (NQBio), Federal University of São João Del Rei, Divinópolis, MG, Brazil
| | | | | | - Alex Guterres Taranto
- Research Center on Biological Chemistry (NQBio), Federal University of São João Del Rei, Divinópolis, MG, Brazil
| | - Domingos de Jesus Rodrigues
- Center for Biodiversity Studies in the Amazon Region of Mato Grosso (NEBAM), Federal University of Mato Grosso, MT, Brazil
| | | | | | - Fernando de Pilla Varotti
- Research Center on Biological Chemistry (NQBio), Federal University of São João Del Rei, Divinópolis, MG, Brazil
| | - Bruno Antonio Marinho Sanchez
- Laboratory of Immunopathology and Tropical Diseases, Health Education and Research Center (NUPADS), Institute of Health Sciences, Federal University of Mato Grosso, Sinop, MT, Brazil
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15
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Wang M, Wang J. Glucose transporter GLUT1 influences Plasmodium berghei infection in Anopheles stephensi. Parasit Vectors 2020; 13:285. [PMID: 32503601 PMCID: PMC7275331 DOI: 10.1186/s13071-020-04155-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Accepted: 05/28/2020] [Indexed: 12/04/2022] Open
Abstract
Background Sugar-feeding provides energy for mosquitoes. Facilitated glucose transporters (GLUTs) are responsible for the uptake of glucose in animals. However, knowledge of GLUTs function in Anopheles spp. is limited. Methods Phylogenetic analysis of GLUTs in Anopheles stephensi was performed by the maximum likelihood and Bayesian inference methods. The spatial and temporal expression patterns of four Asteglut genes were analyzed by qPCR. The function of Asteglut1 was examined using a dsRNA-mediated RNA interference method. Transcriptome analysis was used to investigate the global influence of Asteglut1 on mosquito physiology. Results We identified 4 glut genes, Asteglut1, Asteglutx, Asteglut3 and Asteglut4 in An. stephensi. Asteglut1, Asteglut3 and Asteglut4 were mainly expressed in the midgut. Plasmodium berghei infection differentially regulated the expression of Asteglut genes with significant downregulation of Asteglut1 and Asteglut4, while upregulation of Asteglutx. Only knocking-down Asteglut1 facilitated Plasmodium berghei infection in An. stephensi. This might be due to the accumulation of glucose prior to blood-feeding in dsAsteglut1-treated mosquitoes. Our transcriptome analysis revealed that knockdown of Asteglut1 differentially regulated expression of genes associated with multiple functional clusters, especially those related to detoxification and immunity. The dysregulation of multiple pathways might contribute to the increased P. berghei infection. Conclusions Our study shows that Asteglut1 participates in defense against P. berghei in An. stephensi. The regulation of Asteglut1 on vector competence might through modulating multiple biological processes, such as detoxification and immunity.![]()
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16
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Molbaek K, Tejada M, Ricke CH, Scharff-Poulsen P, Ellekvist P, Helix-Nielsen C, Kumar N, Klaerke DA, Pedersen PA. Purification and initial characterization of Plasmodium falciparum K + channels, PfKch1 and PfKch2 produced in Saccharomyces cerevisiae. Microb Cell Fact 2020; 19:183. [PMID: 32957994 PMCID: PMC7507820 DOI: 10.1186/s12934-020-01437-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Accepted: 09/09/2020] [Indexed: 02/07/2023] Open
Abstract
Resistance towards known antimalarial drugs poses a significant problem, urging for novel drugs that target vital proteins in the malaria parasite Plasmodium falciparum. However, recombinant production of malaria proteins is notoriously difficult. To address this, we have investigated two putative K+ channels, PfKch1 and PfKch2, identified in the P. falciparum genome. We show that PfKch1 and PfKch2 and a C-terminally truncated version of PfKch1 (PfKch11−1094) could indeed be functionally expressed in vivo, since a K+-uptake deficient Saccharomyces cerevisiae strain was complemented by the P. falciparum cDNAs. PfKch11−1094-GFP and GFP-PfKch2 fusion proteins were overexpressed in yeast, purified and reconstituted in lipid bilayers to determine their electrophysiological activity. Single channel conductance amounted to 16 ± 1 pS for PfKch11−1094-GFP and 28 ± 2 pS for GFP-PfKch2. We predicted regulator of K+-conductance (RCK) domains in the C-terminals of both channels, and we accordingly measured channel activity in the presence of Ca2+.
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Affiliation(s)
- Karen Molbaek
- Department of Veterinary and Animal Sciences, University of Copenhagen, Frederiksberg, 1870, Denmark.,Department of Biology, University of Copenhagen, Copenhagen, 2100, Denmark
| | - Maria Tejada
- Department of Veterinary and Animal Sciences, University of Copenhagen, Frederiksberg, 1870, Denmark
| | - Christina Hoeier Ricke
- Department of Veterinary and Animal Sciences, University of Copenhagen, Frederiksberg, 1870, Denmark
| | - Peter Scharff-Poulsen
- Department of Veterinary and Animal Sciences, University of Copenhagen, Frederiksberg, 1870, Denmark
| | - Peter Ellekvist
- Medical Department, Herlev-Gentofte Hospital, Herlev, 2730, Denmark
| | - Claus Helix-Nielsen
- Aquaporin A/S, Kgs Lyngby, 2800, Denmark.,Department of Environmental Engineering, Technical University of Denmark, Kgs Lyngby, 2800, Denmark.,University of Maribor, Laboratory for Water Biophysics and Membrane Technology, Maribor, 2000, Slovenia
| | - Nirbhay Kumar
- Department of Global Health, Milken Institute School of Public Health, George Washington University, Washington DC, 20052-0066, USA
| | - Dan A Klaerke
- Department of Veterinary and Animal Sciences, University of Copenhagen, Frederiksberg, 1870, Denmark.
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17
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Kitowski A, Bernardes GJL. A Sweet Galactose Transfer: Metabolic Oligosaccharide Engineering as a Tool To Study Glycans in Plasmodium Infection. Chembiochem 2020; 21:2696-2700. [PMID: 32289201 PMCID: PMC7540713 DOI: 10.1002/cbic.202000226] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Indexed: 12/13/2022]
Abstract
The introduction of chemical reporter groups into glycan structures through metabolic oligosaccharide engineering (MOE) followed by bio-orthogonal ligation is an important tool to study glycosylation. We show the incorporation of synthetic galactose derivatives that bear terminal alkene groups in hepatic cells, with and without infection by Plasmodium berghei parasites, the causative agent of malaria. Additionally, we demonstrated the contribution of GLUT1 to the transport of these galactose derivatives, and observed a consistent increase in the uptake of these compounds going from naïve to P. berghei-infected cells. Finally, we used MOE to study the interplay between Plasmodium parasites and their mosquito hosts, to reveal a possible transfer of galactose building blocks from the latter to the former. This strategy has the potential to provide new insights into Plasmodium glycobiology as well as for the identification and characterization of key glycan structures for further vaccine development.
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Affiliation(s)
- Annabel Kitowski
- Instituto de Medicina Molecular João Lobo AntunesFaculdade de MedicinaUniversidade de LisboaAvenida Professor Egas Moniz1649-028LisboaPortugal
| | - Gonçalo J. L. Bernardes
- Instituto de Medicina Molecular João Lobo AntunesFaculdade de MedicinaUniversidade de LisboaAvenida Professor Egas Moniz1649-028LisboaPortugal
- Department of ChemistryUniversity of CambridgeLensfield RoadCambridgeCB2 1EWUK
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18
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Jiang X, Yuan Y, Huang J, Zhang S, Luo S, Wang N, Pu D, Zhao N, Tang Q, Hirata K, Yang X, Jiao Y, Sakata-Kato T, Wu JW, Yan C, Kato N, Yin H, Yan N. Structural Basis for Blocking Sugar Uptake into the Malaria Parasite Plasmodium falciparum. Cell 2020; 183:258-268.e12. [PMID: 32860739 DOI: 10.1016/j.cell.2020.08.015] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Revised: 07/08/2020] [Accepted: 08/07/2020] [Indexed: 11/25/2022]
Abstract
Plasmodium species, the causative agent of malaria, rely on glucose for energy supply during blood stage. Inhibition of glucose uptake thus represents a potential strategy for the development of antimalarial drugs. Here, we present the crystal structures of PfHT1, the sole hexose transporter in the genome of Plasmodium species, at resolutions of 2.6 Å in complex with D-glucose and 3.7 Å with a moderately selective inhibitor, C3361. Although both structures exhibit occluded conformations, binding of C3361 induces marked rearrangements that result in an additional pocket. This inhibitor-binding-induced pocket presents an opportunity for the rational design of PfHT1-specific inhibitors. Among our designed C3361 derivatives, several exhibited improved inhibition of PfHT1 and cellular potency against P. falciparum, with excellent selectivity to human GLUT1. These findings serve as a proof of concept for the development of the next-generation antimalarial chemotherapeutics by simultaneously targeting the orthosteric and allosteric sites of PfHT1.
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Affiliation(s)
- Xin Jiang
- State Key Laboratory of Membrane Biology, Tsinghua University, Beijing 100084, China; Beijing Advanced Innovation Center for Structural Biology, Tsinghua University, Beijing 100084, China; Tsinghua-Peking Joint Center for Life Sciences, Tsinghua University, Beijing 100084, China; School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Yafei Yuan
- State Key Laboratory of Membrane Biology, Tsinghua University, Beijing 100084, China; Beijing Advanced Innovation Center for Structural Biology, Tsinghua University, Beijing 100084, China; School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Jian Huang
- Beijing Advanced Innovation Center for Structural Biology, Tsinghua University, Beijing 100084, China; Tsinghua-Peking Joint Center for Life Sciences, Tsinghua University, Beijing 100084, China; Department of Chemistry, Tsinghua University, Beijing 100084, China
| | - Shuo Zhang
- State Key Laboratory of Membrane Biology, Tsinghua University, Beijing 100084, China; Beijing Advanced Innovation Center for Structural Biology, Tsinghua University, Beijing 100084, China; Tsinghua-Peking Joint Center for Life Sciences, Tsinghua University, Beijing 100084, China; School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Shuchen Luo
- Beijing Advanced Innovation Center for Structural Biology, Tsinghua University, Beijing 100084, China; Tsinghua-Peking Joint Center for Life Sciences, Tsinghua University, Beijing 100084, China; Department of Chemistry, Tsinghua University, Beijing 100084, China
| | - Nan Wang
- State Key Laboratory of Membrane Biology, Tsinghua University, Beijing 100084, China; Beijing Advanced Innovation Center for Structural Biology, Tsinghua University, Beijing 100084, China; Tsinghua-Peking Joint Center for Life Sciences, Tsinghua University, Beijing 100084, China; School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Debing Pu
- Beijing Advanced Innovation Center for Structural Biology, Tsinghua University, Beijing 100084, China; Tsinghua-Peking Joint Center for Life Sciences, Tsinghua University, Beijing 100084, China; School of Pharmaceutical Sciences, Tsinghua University, Beijing 100084, China
| | - Na Zhao
- Global Health Drug Discovery Institute, Zhongguancun Dongsheng International Science Park, 1 North Yongtaizhuang Road, Beijing 100192, China
| | - Qingxuan Tang
- Beijing Advanced Innovation Center for Structural Biology, Tsinghua University, Beijing 100084, China; Tsinghua-Peking Joint Center for Life Sciences, Tsinghua University, Beijing 100084, China; School of Pharmaceutical Sciences, Tsinghua University, Beijing 100084, China
| | - Kunio Hirata
- Advanced Photon Technology Division, Research Infrastructure Group, SR Life Science Instrumentation Unit, RIKEN/SPring-8 Center, Hyogo 679-5148, Japan
| | - Xikang Yang
- Beijing Advanced Innovation Center for Structural Biology, Tsinghua University, Beijing 100084, China; Tsinghua-Peking Joint Center for Life Sciences, Tsinghua University, Beijing 100084, China; Department of Chemistry, Tsinghua University, Beijing 100084, China
| | - Yaqing Jiao
- Global Health Drug Discovery Institute, Zhongguancun Dongsheng International Science Park, 1 North Yongtaizhuang Road, Beijing 100192, China
| | - Tomoyo Sakata-Kato
- Global Health Drug Discovery Institute, Zhongguancun Dongsheng International Science Park, 1 North Yongtaizhuang Road, Beijing 100192, China
| | - Jia-Wei Wu
- Institute of Molecular Enzymology, Soochow University, Suzhou, Jiangsu 215123, China
| | - Chuangye Yan
- State Key Laboratory of Membrane Biology, Tsinghua University, Beijing 100084, China; Beijing Advanced Innovation Center for Structural Biology, Tsinghua University, Beijing 100084, China; Tsinghua-Peking Joint Center for Life Sciences, Tsinghua University, Beijing 100084, China; School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Nobutaka Kato
- Global Health Drug Discovery Institute, Zhongguancun Dongsheng International Science Park, 1 North Yongtaizhuang Road, Beijing 100192, China
| | - Hang Yin
- Beijing Advanced Innovation Center for Structural Biology, Tsinghua University, Beijing 100084, China; Tsinghua-Peking Joint Center for Life Sciences, Tsinghua University, Beijing 100084, China; School of Pharmaceutical Sciences, Tsinghua University, Beijing 100084, China.
| | - Nieng Yan
- State Key Laboratory of Membrane Biology, Tsinghua University, Beijing 100084, China; Beijing Advanced Innovation Center for Structural Biology, Tsinghua University, Beijing 100084, China; Tsinghua-Peking Joint Center for Life Sciences, Tsinghua University, Beijing 100084, China; School of Life Sciences, Tsinghua University, Beijing 100084, China.
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19
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20
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Qureshi AA, Suades A, Matsuoka R, Brock J, McComas SE, Nji E, Orellana L, Claesson M, Delemotte L, Drew D. The molecular basis for sugar import in malaria parasites. Nature 2020; 578:321-325. [PMID: 31996846 DOI: 10.1038/s41586-020-1963-z] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Accepted: 01/03/2020] [Indexed: 12/11/2022]
Abstract
Elucidating the mechanism of sugar import requires a molecular understanding of how transporters couple sugar binding and gating events. Whereas mammalian glucose transporters (GLUTs) are specialists1, the hexose transporter from the malaria parasite Plasmodium falciparum PfHT12,3 has acquired the ability to transport both glucose and fructose sugars as efficiently as the dedicated glucose (GLUT3) and fructose (GLUT5) transporters. Here, to establish the molecular basis of sugar promiscuity in malaria parasites, we determined the crystal structure of PfHT1 in complex with D-glucose at a resolution of 3.6 Å. We found that the sugar-binding site in PfHT1 is very similar to those of the distantly related GLUT3 and GLUT5 structures4,5. Nevertheless, engineered PfHT1 mutations made to match GLUT sugar-binding sites did not shift sugar preferences. The extracellular substrate-gating helix TM7b in PfHT1 was positioned in a fully occluded conformation, providing a unique glimpse into how sugar binding and gating are coupled. We determined that polar contacts between TM7b and TM1 (located about 15 Å from D-glucose) are just as critical for transport as the residues that directly coordinate D-glucose, which demonstrates a strong allosteric coupling between sugar binding and gating. We conclude that PfHT1 has achieved substrate promiscuity not by modifying its sugar-binding site, but instead by evolving substrate-gating dynamics.
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Affiliation(s)
- Abdul Aziz Qureshi
- Department of Biochemistry and Biophysics, Stockholm University, Stockholm, Sweden
| | - Albert Suades
- Department of Biochemistry and Biophysics, Stockholm University, Stockholm, Sweden
| | - Rei Matsuoka
- Department of Biochemistry and Biophysics, Stockholm University, Stockholm, Sweden
| | - Joseph Brock
- Department of Biochemistry and Biophysics, Stockholm University, Stockholm, Sweden
| | - Sarah E McComas
- Department of Biochemistry and Biophysics, Stockholm University, Stockholm, Sweden.,Department of Applied Physics, Science for Life Laboratory, KTH Royal Institute of Technology, Stockholm, Sweden
| | - Emmanuel Nji
- Department of Biochemistry and Biophysics, Stockholm University, Stockholm, Sweden
| | - Laura Orellana
- Department of Biochemistry and Biophysics, Stockholm University, Stockholm, Sweden
| | - Magnus Claesson
- Department of Biochemistry and Biophysics, Stockholm University, Stockholm, Sweden
| | - Lucie Delemotte
- Department of Applied Physics, Science for Life Laboratory, KTH Royal Institute of Technology, Stockholm, Sweden
| | - David Drew
- Department of Biochemistry and Biophysics, Stockholm University, Stockholm, Sweden.
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21
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Martin RE. The transportome of the malaria parasite. Biol Rev Camb Philos Soc 2019; 95:305-332. [PMID: 31701663 DOI: 10.1111/brv.12565] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2019] [Revised: 10/02/2019] [Accepted: 10/04/2019] [Indexed: 12/15/2022]
Abstract
Membrane transport proteins, also known as transporters, control the movement of ions, nutrients, metabolites, and waste products across the membranes of a cell and are central to its biology. Proteins of this type also serve as drug targets and are key players in the phenomenon of drug resistance. The malaria parasite has a relatively reduced transportome, with only approximately 2.5% of its genes encoding transporters. Even so, assigning functions and physiological roles to these proteins, and ascertaining their contributions to drug action and drug resistance, has been very challenging. This review presents a detailed critique and synthesis of the disruption phenotypes, protein subcellular localisations, protein functions (observed or predicted), and links to antimalarial drug resistance for each of the parasite's transporter genes. The breadth and depth of the gene disruption data are particularly impressive, with at least one phenotype determined in the parasite's asexual blood stage for each transporter gene, and multiple phenotypes available for 76% of the genes. Analysis of the curated data set revealed there to be relatively little redundancy in the Plasmodium transportome; almost two-thirds of the parasite's transporter genes are essential or required for normal growth in the asexual blood stage of the parasite, and this proportion increased to 78% when the disruption phenotypes available for the other parasite life stages were included in the analysis. These observations, together with the finding that 22% of the transportome is implicated in the parasite's resistance to existing antimalarials and/or drugs within the development pipeline, indicate that transporters are likely to serve, or are already serving, as drug targets. Integration of the different biological and bioinformatic data sets also enabled the selection of candidates for transport processes known to be essential for parasite survival, but for which the underlying proteins have thus far remained undiscovered. These include potential transporters of pantothenate, isoleucine, or isopentenyl diphosphate, as well as putative anion-selective channels that may serve as the pore component of the parasite's 'new permeation pathways'. Other novel insights into the parasite's biology included the identification of transporters for the potential development of antimalarial treatments, transmission-blocking drugs, prophylactics, and genetically attenuated vaccines. The syntheses presented herein set a foundation for elucidating the functions and physiological roles of key members of the Plasmodium transportome and, ultimately, to explore and realise their potential as therapeutic targets.
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Affiliation(s)
- Rowena E Martin
- Research School of Biology, Australian National University, Canberra, Australian Capital Territory, Australia
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22
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To VPTH, Masagounder K, Loewen ME. SLC transporters ASCT2, B 0 AT1-like, y + LAT1, and LAT4-like associate with methionine electrogenic and radio-isotope flux kinetics in rainbow trout intestine. Physiol Rep 2019; 7:e14274. [PMID: 31705630 PMCID: PMC6841986 DOI: 10.14814/phy2.14274] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Accepted: 09/21/2019] [Indexed: 01/08/2023] Open
Abstract
Methionine (Met) is an important building block and metabolite for protein biosynthesis. However, the mechanism behind its absorption in the fish gut has not been elucidated. Here, we describe the fundamental properties of Met transport along trout gut at µmol/L and mmol/L concentration. Both electrogenic and unidirectional DL-[14 C]Met flux were employed to characterize Met transporters in Ussing chambers. Exploiting the differences in gene expression between diploid (2N) and triploid (3N) and intestinal segment as tools, allowed the association between gene and methionine transport. Specifically, three intestinal segments including pyloric caeca (PC), midgut (MG), and hindgut (HG) were assessed. Results at 0-150 µmol/L concentration demonstrated that the DL-Met was most likely transported by apical transporter ASCT2 (SLC1A5) and recycled by basolateral transporter y+ LAT1 (SLC7A7) due to five lines of observation: (1) lack of Na+ -independent kinetics, (2) low expression of B0 AT2-like gene, (3) Na+ -dependent, high-affinity (Km , µmol/L ranges) kinetics in DL-[14 C]Met flux, (4) association mRNA expression with the high-affinity kinetics and (5) electrogenic currents induced by Met. Results at 0.2-20 mmol/L concentration suggested that the DL-Met transport is likely transported by B0 AT1-like (SLC6A19-like) based on gene expression, Na+ -dependence and low-affinity kinetics (Km , mmol/L ranges). Similarly, genomic and gene expression analysis suggest that the basolateral exit of methionine was primarily through LAT4-like transporter (SLC43A2-like). Conclusively, DL-Met uptake in trout gut was most likely governed by Na+ -dependent apical transporters ASCT2 and B0 AT1-like and released through basolateral LAT4-like, with some recycling through y+ LAT1. A comparatively simpler model than that previously described in mammals.
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Affiliation(s)
- Van P. T. H. To
- Veterinary Biomedical SciencesUniversity of SaskatchewanSaskatoonSaskatchewanCanada
| | | | - Matthew E. Loewen
- Veterinary Biomedical SciencesUniversity of SaskatchewanSaskatoonSaskatchewanCanada
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23
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Heitmeier MR, Hresko RC, Edwards RL, Prinsen MJ, Ilagan MXG, Odom John AR, Hruz PW. Identification of druggable small molecule antagonists of the Plasmodium falciparum hexose transporter PfHT and assessment of ligand access to the glucose permeation pathway via FLAG-mediated protein engineering. PLoS One 2019; 14:e0216457. [PMID: 31071153 PMCID: PMC6508677 DOI: 10.1371/journal.pone.0216457] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Accepted: 04/23/2019] [Indexed: 12/03/2022] Open
Abstract
Although the Plasmodium falciparum hexose transporter PfHT has emerged as a promising target for anti-malarial therapy, previously identified small-molecule inhibitors have lacked promising drug-like structural features necessary for development as clinical therapeutics. Taking advantage of emerging insight into structure/function relationships in homologous facilitative hexose transporters and our novel high throughput screening platform, we investigated the ability of compounds satisfying Lipinksi rules for drug likeness to directly interact and inhibit PfHT. The Maybridge HitFinder chemical library was interrogated by searching for compounds that reduce intracellular glucose by >40% at 10 μM. Testing of initial hits via measurement of 2-deoxyglucose (2-DG) uptake in PfHT over-expressing cell lines identified 6 structurally unique glucose transport inhibitors. WU-1 (3-(2,6-dichlorophenyl)-5-methyl-N-[2-(4-methylbenzenesulfonyl)ethyl]-1,2-oxazole-4-carboxamide) blocked 2-DG uptake (IC50 = 5.8 ± 0.6 μM) with minimal effect on the human orthologue class I (GLUTs 1-4), class II (GLUT8) and class III (GLUT5) facilitative glucose transporters. WU-1 showed comparable potency in blocking 2-DG uptake in freed parasites and inhibiting parasite growth, with an IC50 of 6.1 ± 0.8 μM and EC50 of 5.5 ± 0.6 μM, respectively. WU-1 also directly competed for N-[2-[2-[2-[(N-biotinylcaproylamino)ethoxy)ethoxyl]-4-[2-(trifluoromethyl)-3H-diazirin-3-yl]benzoyl]-1,3-bis(mannopyranosyl-4-yloxy)-2-propylamine (ATB-BMPA) binding and inhibited the transport of D-glucose with an IC50 of 5.9 ± 0.8 μM in liposomes containing purified PfHT. Kinetic analysis revealed that WU-1 acts as a non-competitive inhibitor of zero-trans D-fructose uptake. Decreased potency for WU-1 and the known endofacial ligand cytochalasin B was observed when PfHT was engineered to contain an N-terminal FLAG tag. This modification resulted in a concomitant increase in affinity for 4,6-O-ethylidene-α-D-glucose, an exofacially directed transport antagonist, but did not alter the Km for 2-DG. Taken together, these data are consistent with a model in which WU-1 binds preferentially to the transporter in an inward open conformation and support the feasibility of developing potent and selective PfHT antagonists as a novel class of anti-malarial drugs.
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Affiliation(s)
- Monique R. Heitmeier
- Department of Pediatrics, Washington University School of Medicine, St Louis, MO, United States of America
| | - Richard C. Hresko
- Department of Pediatrics, Washington University School of Medicine, St Louis, MO, United States of America
| | - Rachel L. Edwards
- Department of Pediatrics, Washington University School of Medicine, St Louis, MO, United States of America
| | - Michael J. Prinsen
- High Throughput Screening Center, Washington University School of Medicine, St Louis, MO, United States of America
| | - Ma Xenia G. Ilagan
- High Throughput Screening Center, Washington University School of Medicine, St Louis, MO, United States of America
| | - Audrey R. Odom John
- Department of Pediatrics, Washington University School of Medicine, St Louis, MO, United States of America
- Department of Molecular Microbiology, Washington University School of Medicine, St Louis, MO, United States of America
| | - Paul W. Hruz
- Department of Pediatrics, Washington University School of Medicine, St Louis, MO, United States of America
- Department of Cell Biology and Physiology, Washington University School of Medicine, St Louis, MO, United States of America
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24
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Abstract
Increased understanding of fructose metabolism, which begins with uptake via the intestine, is important because fructose now constitutes a physiologically significant portion of human diets and is associated with increased incidence of certain cancers and metabolic diseases. New insights in our knowledge of intestinal fructose absorption mediated by the facilitative glucose transporter GLUT5 in the apical membrane and by GLUT2 in the basolateral membrane are reviewed. We begin with studies related to structure as well as ligand binding, then revisit the controversial proposition that apical GLUT2 is the main mediator of intestinal fructose absorption. The review then describes how dietary fructose may be sensed by intestinal cells to affect the expression and activity of transporters and fructolytic enzymes, to interact with the transport of certain minerals and electrolytes, and to regulate portal and peripheral fructosemia and glycemia. Finally, it discusses the potential contributions of dietary fructose to gastrointestinal diseases and to the gut microbiome.
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Affiliation(s)
- Ronaldo P Ferraris
- Department of Pharmacology, Physiology and Neuroscience, New Jersey Medical School, Rutgers University, Newark, New Jersey 07946, USA;
| | - Jun-Yong Choe
- Department of Biochemistry and Molecular Biology, Rosalind Franklin University of Medicine and Science, The Chicago Medical School, North Chicago, Illinois 60064, USA;
| | - Chirag R Patel
- Independent Drug Safety Consulting, Wilmington, Delaware 19803, USA;
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25
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Carey MA, Papin JA, Guler JL. Novel Plasmodium falciparum metabolic network reconstruction identifies shifts associated with clinical antimalarial resistance. BMC Genomics 2017; 18:543. [PMID: 28724354 PMCID: PMC5518114 DOI: 10.1186/s12864-017-3905-1] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Accepted: 06/27/2017] [Indexed: 02/06/2023] Open
Abstract
Background Malaria remains a major public health burden and resistance has emerged to every antimalarial on the market, including the frontline drug, artemisinin. Our limited understanding of Plasmodium biology hinders the elucidation of resistance mechanisms. In this regard, systems biology approaches can facilitate the integration of existing experimental knowledge and further understanding of these mechanisms. Results Here, we developed a novel genome-scale metabolic network reconstruction, iPfal17, of the asexual blood-stage P. falciparum parasite to expand our understanding of metabolic changes that support resistance. We identified 11 metabolic tasks to evaluate iPfal17 performance. Flux balance analysis and simulation of gene knockouts and enzyme inhibition predict candidate drug targets unique to resistant parasites. Moreover, integration of clinical parasite transcriptomes into the iPfal17 reconstruction reveals patterns associated with antimalarial resistance. These results predict that artemisinin sensitive and resistant parasites differentially utilize scavenging and biosynthetic pathways for multiple essential metabolites, including folate and polyamines. Our findings are consistent with experimental literature, while generating novel hypotheses about artemisinin resistance and parasite biology. We detect evidence that resistant parasites maintain greater metabolic flexibility, perhaps representing an incomplete transition to the metabolic state most appropriate for nutrient-rich blood. Conclusion Using this systems biology approach, we identify metabolic shifts that arise with or in support of the resistant phenotype. This perspective allows us to more productively analyze and interpret clinical expression data for the identification of candidate drug targets for the treatment of resistant parasites. Electronic supplementary material The online version of this article (doi:10.1186/s12864-017-3905-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Maureen A Carey
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia, School of Medicine, Charlottesville, USA
| | - Jason A Papin
- Department of Biomedical Engineering, University of Virginia, Charlottesville, USA.
| | - Jennifer L Guler
- Department of Biology, University of Virginia, Charlottesville, USA. .,Division of Infectious Diseases and International Health, University of Virginia, School of Medicine, Charlottesville, USA.
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26
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Soueidan OM, Scully TW, Kaur J, Panigrahi R, Belovodskiy A, Do V, Matier CD, Lemieux MJ, Wuest F, Cheeseman C, West FG. Fluorescent Hexose Conjugates Establish Stringent Stereochemical Requirement by GLUT5 for Recognition and Transport of Monosaccharides. ACS Chem Biol 2017; 12:1087-1094. [PMID: 28205432 DOI: 10.1021/acschembio.6b01101] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The specificity characteristics of transporters can be exploited for the development of novel diagnostic therapeutic probes. The facilitated hexose transporter family (GLUTs) has a distinct set of preferences for monosaccharide substrates, and while some are expressed ubiquitously (e.g., GLUT1), others are quite tissue specific (e.g., GLUT5, which is overexpressed in some breast cancer tissues). While these differences have enabled the development of new molecular probes based upon hexose- and tissue-selective uptake, substrate design for compounds targeting these GLUT transporters has been encumbered by a limited understanding of the molecular interactions at play in hexose binding and transport. Four new fluorescently labeled hexose derivatives have been prepared, and their transport characteristics were examined in two breast cancer cell lines expressing mainly GLUTs 1, 2, and 5. Our results demonstrate, for the first time, a stringent stereochemical requirement for recognition and transport by GLUT5. 6-NBDF, in which all substituents are in the d-fructose configuration, is taken up rapidly into both cell lines via GLUT5. On the other hand, inversion of a single stereocenter at C-3 (6-NBDP), C-4 (6-NBDT), or C-5 (6-NDBS) results in selective transport via GLUT1. An in silico docking study employing the recently published GLUT5 crystal structure confirms this stereochemical dependence. This work provides insight into hexose-GLUT interactions at the molecular level and will facilitate structure-based design of novel substrates targeting individual members of the GLUT family and forms the basis of new cancer imaging or therapeutic agents.
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Affiliation(s)
- Olivier-Mohamad Soueidan
- Department
of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, Alberta, Canada T6G 2G2
- Department
of Physiology, University of Alberta, 7-55 Medical Sciences Building, Edmonton, Alberta, Canada T6G 2H7
| | - Thomas W. Scully
- Department
of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, Alberta, Canada T6G 2G2
| | - Jatinder Kaur
- Department
of Oncology, University of Alberta, Cross Cancer Institute, Edmonton, Alberta, Canada T6G 1Z2
| | - Rashmi Panigrahi
- Department
of Biochemistry, University of Alberta, 451 Medical Sciences Building, Edmonton, Alberta, Canada T6G 2H7
| | - Alexandr Belovodskiy
- Department
of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, Alberta, Canada T6G 2G2
| | - Victor Do
- Department
of Physiology, University of Alberta, 7-55 Medical Sciences Building, Edmonton, Alberta, Canada T6G 2H7
| | - Carson D. Matier
- Department
of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, Alberta, Canada T6G 2G2
| | - M. Joanne Lemieux
- Department
of Biochemistry, University of Alberta, 451 Medical Sciences Building, Edmonton, Alberta, Canada T6G 2H7
| | - Frank Wuest
- Department
of Oncology, University of Alberta, Cross Cancer Institute, Edmonton, Alberta, Canada T6G 1Z2
| | - Chris Cheeseman
- Department
of Physiology, University of Alberta, 7-55 Medical Sciences Building, Edmonton, Alberta, Canada T6G 2H7
| | - F. G. West
- Department
of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, Alberta, Canada T6G 2G2
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27
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Meireles P, Sales-Dias J, Andrade CM, Mello-Vieira J, Mancio-Silva L, Simas JP, Staines HM, Prudêncio M. GLUT1-mediated glucose uptake plays a crucial role during Plasmodium hepatic infection. Cell Microbiol 2016; 19. [PMID: 27404888 PMCID: PMC5297879 DOI: 10.1111/cmi.12646] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2016] [Revised: 06/20/2016] [Accepted: 07/06/2016] [Indexed: 02/06/2023]
Abstract
Intracellular pathogens have evolved mechanisms to ensure their survival and development inside their host cells. Here, we show that glucose is a pivotal modulator of hepatic infection by the rodent malaria parasite Plasmodium berghei and that glucose uptake via the GLUT1 transporter is specifically enhanced in P. berghei‐infected cells. We further show that ATP levels of cells containing developing parasites are decreased, which is known to enhance membrane GLUT1 activity. In addition, GLUT1 molecules are translocated to the membrane of the hepatic cell, increasing glucose uptake at later stages of infection. Chemical inhibition of GLUT1 activity leads to a decrease in glucose uptake and the consequent impairment of hepatic infection, both in vitro and in vivo. Our results reveal that changes in GLUT1 conformation and cellular localization seem to be part of an adaptive host response to maintain adequate cellular nutrition and energy levels, ensuring host cell survival and supporting P. berghei hepatic development.
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Affiliation(s)
- Patrícia Meireles
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Joana Sales-Dias
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Carolina M Andrade
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - João Mello-Vieira
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Liliana Mancio-Silva
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - J Pedro Simas
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Henry M Staines
- Institute for Infection & Immunity, St. George's, University of London, Cranmer Terrace, London, UK
| | - Miguel Prudêncio
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
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28
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Fonseca ALD, Nunes RR, Braga VML, Comar M, Alves RJ, Varotti FDP, Taranto AG. Docking, QM/MM, and molecular dynamics simulations of the hexose transporter from Plasmodium falciparum (PfHT). J Mol Graph Model 2016; 66:174-86. [PMID: 27131282 DOI: 10.1016/j.jmgm.2016.03.015] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Revised: 03/14/2016] [Accepted: 03/24/2016] [Indexed: 01/19/2023]
Abstract
Malaria is the most prevalent parasitic disease in the world. Currently, an effective vaccine for malaria does not exist, and chemotherapy must be used to treat the disease. Because of increasing resistance to current antimalarial drugs, new treatments must be developed. Among the many potential molecular targets, the hexose transporter of Plasmodium falciparum (PfHT) is particularly promising because it plays a vital role in glucose transport for the parasite. Thus, this study aims to determine the three-dimensional structure of PfHT and to describe the intermolecular interactions between active glycoside derivatives and PfHT. Such information should aid in the development of new antimalarial drugs. The receptor PfHT was constructed from primary sequences deposited in the SWISS MODEL database. Next, molecular docking simulations between O-(undec-10-en)-l-D-glucose and the constructed active site models were performed using Autodock Vina. The glycoside derivative-PfHT complexes were then refined using the hybrid QM/MM (PM3/ff03) method within the AMBER package. The models were then evaluated using Ramachandran plots, which indicated that 93.2% of the residues in the refined PfHT models (P5) were present in favorable regions. Furthermore, graphical plots using ANOLEA showed that the potential energies of interaction for atoms unbonded to P5 were negative. Finally, the O-(undec-10-en)-l-D-glucose-PfHT complex was evaluated using 20-ns Molecular Dynamics simulations with an ff03 force field. Docking and QM/MM studies revealed the amino acids essential for molecular recognition of and activity on glycosides. Inhibition of glucose transporters may prevent the development and metabolism of P. falciparum, so a description of the receptor's structure is a critical step towards rational drug design.
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Affiliation(s)
- Amanda Luisa da Fonseca
- Núcleo de Pesquisa em Química Biológica, Universidade Federal de São João del-Rei, Divinópolis, MG, Brazil; Laboratório de Modelagem Molecular, Universidade Federal de São João del-Rei, Divinópolis, MG, Brazil; Laboratório de Química Medicinal Farmacêutica, Universidade Federal de São João del-Rei, Divinópolis, MG, Brazil
| | - Renata Rachide Nunes
- Laboratório de Química Medicinal Farmacêutica, Universidade Federal de São João del-Rei, Divinópolis, MG, Brazil
| | - Vanildo Martins Lima Braga
- Laboratório de Química Medicinal Farmacêutica, Universidade Federal de São João del-Rei, Divinópolis, MG, Brazil
| | - Moacyr Comar
- Laboratório de Modelagem Molecular, Universidade Federal de São João del-Rei, Divinópolis, MG, Brazil
| | - Ricardo José Alves
- Laboratório de Química, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Fernando de Pilla Varotti
- Núcleo de Pesquisa em Química Biológica, Universidade Federal de São João del-Rei, Divinópolis, MG, Brazil
| | - Alex Gutterres Taranto
- Laboratório de Química Medicinal Farmacêutica, Universidade Federal de São João del-Rei, Divinópolis, MG, Brazil.
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29
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Cova M, Rodrigues JA, Smith TK, Izquierdo L. Sugar activation and glycosylation in Plasmodium. Malar J 2015; 14:427. [PMID: 26520586 PMCID: PMC4628283 DOI: 10.1186/s12936-015-0949-z] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2015] [Accepted: 10/21/2015] [Indexed: 11/24/2022] Open
Abstract
Glycoconjugates are important mediators of host-pathogen interactions and are usually very abundant in the surface of many protozoan parasites. However, in the particular case of Plasmodium species, previous works show that glycosylphosphatidylinositol anchor modifications, and to an unknown extent, a severely truncated N-glycosylation are the only glycosylation processes taking place in the parasite. Nevertheless, a detailed analysis of the parasite genome and the recent identification of the sugar nucleotide precursors biosynthesized by Plasmodium falciparum support a picture in which several overlooked, albeit not very prominent glycosylations may be occurring during the parasite life cycle. In this work,
the authors review recent developments in the characterization of the biosynthesis of glycosylation precursors in the parasite, focusing on the outline of the possible fates of these precursors.
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Affiliation(s)
- Marta Cova
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic, Universitat de Barcelona, Barcelona, Spain.
| | - João A Rodrigues
- Instituto de Medicina Molecular, Faculdade de Medicina da Universidade de Lisboa, Av. Prof. Egas Moniz, Edificio Egas Moniz, 1649-028, Lisbon, Portugal.
| | - Terry K Smith
- Biomedical Sciences Research Complex, University of St Andrews, North Haugh, St Andrews, Fife, KY16 9ST, UK.
| | - Luis Izquierdo
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic, Universitat de Barcelona, Barcelona, Spain.
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30
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Spillman NJ, Kirk K. The malaria parasite cation ATPase PfATP4 and its role in the mechanism of action of a new arsenal of antimalarial drugs. INTERNATIONAL JOURNAL FOR PARASITOLOGY-DRUGS AND DRUG RESISTANCE 2015; 5:149-62. [PMID: 26401486 PMCID: PMC4559606 DOI: 10.1016/j.ijpddr.2015.07.001] [Citation(s) in RCA: 76] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Revised: 07/03/2015] [Accepted: 07/08/2015] [Indexed: 11/28/2022]
Abstract
The intraerythrocytic malaria parasite, Plasmodium falciparum, maintains a low cytosolic Na(+) concentration and the plasma membrane P-type cation translocating ATPase 'PfATP4' has been implicated as playing a key role in this process. PfATP4 has been the subject of significant attention in recent years as mutations in this protein confer resistance to a growing number of new antimalarial compounds, including the spiroindolones, the pyrazoles, the dihydroisoquinolones, and a number of the antimalarial agents in the Medicines for Malaria Venture's 'Malaria Box'. On exposure of parasites to these compounds there is a rapid disruption of cytosolic Na(+). Whether, and if so how, such chemically distinct compounds interact with PfATP4, and how such interactions lead to parasite death, is not yet clear. The fact that multiple different chemical classes have converged upon PfATP4 highlights its significance as a potential target for new generation antimalarial agents. A spiroindolone (KAE609, now known as cipargamin) has progressed through Phase I and IIa clinical trials with favourable results. In this review we consider the physiological role of PfATP4, summarise the current repertoire of antimalarial compounds for which PfATP4 is implicated in their mechanism of action, and provide an outlook on translation from target identification in the laboratory to patient treatment in the field.
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Affiliation(s)
- Natalie Jane Spillman
- Research School of Biology, The Australian National University, Canberra, Australian Capital Territory 2601, Australia ; Department of Medicine (Infectious Diseases), Washington University School of Medicine, Saint Louis, MO 63110, USA
| | - Kiaran Kirk
- Research School of Biology, The Australian National University, Canberra, Australian Capital Territory 2601, Australia
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31
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A lactate and formate transporter in the intraerythrocytic malaria parasite, Plasmodium falciparum. Nat Commun 2015; 6:6721. [PMID: 25823844 DOI: 10.1038/ncomms7721] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2013] [Accepted: 02/23/2015] [Indexed: 12/24/2022] Open
Abstract
The intraerythrocytic malaria parasite relies primarily on glycolysis to fuel its rapid growth and reproduction. The major byproduct of this metabolism, lactic acid, is extruded into the external medium. In this study, we show that the human malaria parasite Plasmodium falciparum expresses at its surface a member of the microbial formate-nitrite transporter family (PfFNT), which, when expressed in Xenopus laevis oocytes, transports both formate and lactate. The transport characteristics of PfFNT in oocytes (pH-dependence, inhibitor-sensitivity and kinetics) are similar to those of the transport of lactate and formate across the plasma membrane of mature asexual-stage P. falciparum trophozoites, consistent with PfFNT playing a major role in the efflux of lactate and hence in the energy metabolism of the intraerythrocytic parasite.
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32
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Penkler G, du Toit F, Adams W, Rautenbach M, Palm DC, van Niekerk DD, Snoep JL. Construction and validation of a detailed kinetic model of glycolysis in Plasmodium falciparum. FEBS J 2015; 282:1481-511. [PMID: 25693925 DOI: 10.1111/febs.13237] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2014] [Revised: 02/07/2015] [Accepted: 02/13/2015] [Indexed: 11/26/2022]
Abstract
UNLABELLED The enzymes in the Embden-Meyerhof-Parnas pathway of Plasmodium falciparum trophozoites were kinetically characterized and their integrated activities analyzed in a mathematical model. For validation of the model, we compared model predictions for steady-state fluxes and metabolite concentrations of the hexose phosphates with experimental values for intact parasites. The model, which is completely based on kinetic parameters that were measured for the individual enzymes, gives an accurate prediction of the steady-state fluxes and intermediate concentrations. This is the first detailed kinetic model for glucose metabolism in P. falciparum, one of the most prolific malaria-causing protozoa, and the high predictive power of the model makes it a strong tool for future drug target identification studies. The modelling workflow is transparent and reproducible, and completely documented in the SEEK platform, where all experimental data and model files are available for download. DATABASE The mathematical models described in the present study have been submitted to the JWS Online Cellular Systems Modelling Database (http://jjj.bio.vu.nl/database/penkler). The investigation and complete experimental data set is available on SEEK (10.15490/seek.1. INVESTIGATION 56).
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Affiliation(s)
- Gerald Penkler
- Department of Biochemistry, Stellenbosch University, Matieland, South Africa; Molecular Cell Physiology, Vrije Universiteit Amsterdam, The Netherlands
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33
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New insight into the mechanism of accumulation and intraerythrocytic compartmentation of albitiazolium, a new type of antimalarial. Antimicrob Agents Chemother 2014; 58:5519-27. [PMID: 25001307 DOI: 10.1128/aac.00040-14] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Bis-thiazolium salts constitute a new class of antihematozoan drugs that inhibit parasite phosphatidylcholine biosynthesis. They specifically accumulate in Plasmodium- and Babesia-infected red blood cells (IRBC). Here, we provide new insight into the choline analogue albitiazolium, which is currently being clinically tested against severe malaria. Concentration-dependent accumulation in P. falciparum-infected erythrocytes reached steady state after 90 to 120 min and was massive throughout the blood cycle, with cellular accumulation ratios of up to 1,000. This could not occur through a lysosomotropic effect, and the extent did not depend on the food vacuole pH, which was the case for the weak base chloroquine. Analysis of albitiazolium accumulation in P. falciparum IRBC revealed a high-affinity component that was restricted to mature stages and suppressed by pepstatin A treatment, and thus likely related to drug accumulation in the parasite food vacuole. Albitiazolium also accumulated in a second high-capacity component present throughout the blood cycle that was likely not related to the food vacuole and also observed with Babesia divergens-infected erythrocytes. Accumulation was strictly glucose dependent, drastically inhibited by H+/K+ and Na+ ionophores upon collapse of ionic gradients, and appeared to be energized by the proton-motive force across the erythrocyte plasma membrane, indicating the importance of transport steps for this permanently charged new type of antimalarial agent. This specific, massive, and irreversible accumulation allows albitiazolium to restrict its toxicity to hematozoa-infected erythrocytes. The intraparasitic compartmentation of albitiazolium corroborates a dual mechanism of action, which could make this new type of antimalarial agent resistant to parasite resistance.
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34
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Abstract
As it grows and replicates within the erythrocytes of its host the malaria parasite takes up nutrients from the extracellular medium, exports metabolites and maintains a tight control over its internal ionic composition. These functions are achieved via membrane transport proteins, integral membrane proteins that mediate the passage of solutes across the various membranes that separate the biochemical machinery of the parasite from the extracellular environment. Proteins of this type play a key role in antimalarial drug resistance, as well as being candidate drug targets in their own right. This review provides an overview of recent work on the membrane transport biology of the malaria parasite-infected erythrocyte, encompassing both the parasite-induced changes in the membrane transport properties of the host erythrocyte and the cell physiology of the intracellular parasite itself.
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Dean P, Major P, Nakjang S, Hirt RP, Embley TM. Transport proteins of parasitic protists and their role in nutrient salvage. FRONTIERS IN PLANT SCIENCE 2014; 5:153. [PMID: 24808897 PMCID: PMC4010794 DOI: 10.3389/fpls.2014.00153] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2014] [Accepted: 04/01/2014] [Indexed: 05/02/2023]
Abstract
The loss of key biosynthetic pathways is a common feature of important parasitic protists, making them heavily dependent on scavenging nutrients from their hosts. This is often mediated by specialized transporter proteins that ensure the nutritional requirements of the parasite are met. Over the past decade, the completion of several parasite genome projects has facilitated the identification of parasite transporter proteins. This has been complemented by functional characterization of individual transporters along with investigations into their importance for parasite survival. In this review, we summarize the current knowledge on transporters from parasitic protists and highlight commonalities and differences in the transporter repertoires of different parasitic species, with particular focus on characterized transporters that act at the host-pathogen interface.
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Affiliation(s)
- Paul Dean
- *Correspondence: Paul Dean and T. Martin Embley, The Medical School, Institute for Cell and Molecular Biosciences, Newcastle University, Catherine Cookson Building, Framlington Place, Newcastle upon Tyne, NE2 4HH, UK e-mail: ;
| | | | | | | | - T. Martin Embley
- *Correspondence: Paul Dean and T. Martin Embley, The Medical School, Institute for Cell and Molecular Biosciences, Newcastle University, Catherine Cookson Building, Framlington Place, Newcastle upon Tyne, NE2 4HH, UK e-mail: ;
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Tjhin ET, Staines HM, van Schalkwyk DA, Krishna S, Saliba KJ. Studies with the Plasmodium falciparum hexokinase reveal that PfHT limits the rate of glucose entry into glycolysis. FEBS Lett 2013; 587:3182-7. [PMID: 23954294 DOI: 10.1016/j.febslet.2013.07.052] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2013] [Revised: 07/25/2013] [Accepted: 07/31/2013] [Indexed: 12/16/2022]
Abstract
To characterise plasmodial glycolysis, we generated two transgenic Plasmodium falciparum lines, one expressing P. falciparum hexokinase (PfHK) tagged with GFP (3D7-PfHK(GFP)) and another overexpressing native PfHK (3D7-PfHK(+)). Contrary to previous reports, we propose that PfHK is cytosolic. The glucose analogue, 2-deoxy-d-glucose (2-DG) was nearly 2-fold less toxic to 3D7-PfHK(+) compared with control parasites, supporting PfHK as a potential drug target. Although PfHK activity was higher in 3D7-PfHK(+), they accumulated phospho-[(14)C]2-DG at the same rate as control parasites. Transgenic parasites overexpressing the parasite's glucose transporter (PfHT) accumulated phospho-[(14)C]2-DG at a higher rate, consistent with glucose transport limiting glucose entry into glycolysis.
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Affiliation(s)
- Erick T Tjhin
- Research School of Biology, College of Medicine, Biology and Environment, The Australian National University, Canberra, ACT 0200, Australia
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37
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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] [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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Sanz S, Bandini G, Ospina D, Bernabeu M, Mariño K, Fernández-Becerra C, Izquierdo L. Biosynthesis of GDP-fucose and other sugar nucleotides in the blood stages of Plasmodium falciparum. J Biol Chem 2013; 288:16506-16517. [PMID: 23615908 DOI: 10.1074/jbc.m112.439828] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Carbohydrate structures play important roles in many biological processes, including cell adhesion, cell-cell communication, and host-pathogen interactions. Sugar nucleotides are activated forms of sugars used by the cell as donors for most glycosylation reactions. Using a liquid chromatography-tandem mass spectrometry-based method, we identified and quantified the pools of UDP-glucose, UDP-galactose, UDP-N-acetylglucosamine, GDP-mannose, and GDP-fucose in Plasmodium falciparum intraerythrocytic life stages. We assembled these data with the in silico functional reconstruction of the parasite metabolic pathways obtained from the P. falciparum annotated genome, exposing new active biosynthetic routes crucial for further glycosylation reactions. Fucose is a sugar present in glycoconjugates often associated with recognition and adhesion events. Thus, the GDP-fucose precursor is essential in a wide variety of organisms. P. falciparum presents homologues of GDP-mannose 4,6-dehydratase and GDP-L-fucose synthase enzymes that are active in vitro, indicating that most GDP-fucose is formed by a de novo pathway that involves the bioconversion of GDP-mannose. Homologues for enzymes involved in a fucose salvage pathway are apparently absent in the P. falciparum genome. This is in agreement with in vivo metabolic labeling experiments showing that fucose is not significantly incorporated by the parasite. Fluorescence microscopy of epitope-tagged versions of P. falciparum GDP-mannose 4,6-dehydratase and GDP-L-fucose synthase expressed in transgenic 3D7 parasites shows that these enzymes localize in the cytoplasm of P. falciparum during the intraerythrocytic developmental cycle. Although the function of fucose in the parasite is not known, the presence of GDP-fucose suggests that the metabolite may be used for further fucosylation reactions.
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Affiliation(s)
- Sílvia Sanz
- Barcelona Centre for International Health Research, Hospital Clínic-Universitat de Barcelona, CEK, 1a Planta, Rosselló 149-153, 08036, Barcelona, Spain
| | - Giulia Bandini
- College of Life Sciences, University of Dundee, Division of Biological Chemistry and Drug Discovery, Wellcome Trust Biocentre, Dundee DD15EH, Scotland, United Kingdom
| | - Diego Ospina
- Barcelona Centre for International Health Research, Hospital Clínic-Universitat de Barcelona, CEK, 1a Planta, Rosselló 149-153, 08036, Barcelona, Spain
| | - Maria Bernabeu
- Barcelona Centre for International Health Research, Hospital Clínic-Universitat de Barcelona, CEK, 1a Planta, Rosselló 149-153, 08036, Barcelona, Spain
| | - Karina Mariño
- College of Life Sciences, University of Dundee, Division of Biological Chemistry and Drug Discovery, Wellcome Trust Biocentre, Dundee DD15EH, Scotland, United Kingdom
| | - Carmen Fernández-Becerra
- Barcelona Centre for International Health Research, Hospital Clínic-Universitat de Barcelona, CEK, 1a Planta, Rosselló 149-153, 08036, Barcelona, Spain
| | - Luis Izquierdo
- Barcelona Centre for International Health Research, Hospital Clínic-Universitat de Barcelona, CEK, 1a Planta, Rosselló 149-153, 08036, Barcelona, Spain.
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39
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Preuss J, Jortzik E, Becker K. Glucose-6-phosphate metabolism in Plasmodium falciparum. IUBMB Life 2012; 64:603-11. [PMID: 22639416 DOI: 10.1002/iub.1047] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2012] [Accepted: 04/07/2012] [Indexed: 01/13/2023]
Abstract
Malaria is still one of the most threatening diseases worldwide. The high drug resistance rates of malarial parasites make its eradication difficult and furthermore necessitate the development of new antimalarial drugs. Plasmodium falciparum is responsible for severe malaria and therefore of special interest with regard to drug development. Plasmodium parasites are highly dependent on glucose and very sensitive to oxidative stress; two observations that drew interest to the pentose phosphate pathway (PPP) with its key enzyme glucose-6-phosphate dehydrogenase (G6PD). A central position of the PPP for malaria parasites is supported by the fact that human G6PD deficiency protects to a certain degree from malaria infections. Plasmodium parasites and the human host possess a complete PPP, both of which seem to be important for the parasites. Interestingly, there are major differences between parasite and human G6PD, making the enzyme of Plasmodium a promising target for antimalarial drug design. This review gives an overview of the current state of research on glucose-6-phosphate metabolism in P. falciparum and its impact on malaria infections. Moreover, the unique characteristics of the enzyme G6PD in P. falciparum are discussed, upon which its current status as promising target for drug development is based.
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Affiliation(s)
- Janina Preuss
- Chair of Biochemistry and Molecular Biology, Interdisciplinary Research Center, Justus Liebig University, Giessen, Germany
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40
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Slavic K, Krishna S, Derbyshire ET, Staines HM. Plasmodial sugar transporters as anti-malarial drug targets and comparisons with other protozoa. Malar J 2011; 10:165. [PMID: 21676209 PMCID: PMC3135577 DOI: 10.1186/1475-2875-10-165] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2011] [Accepted: 06/15/2011] [Indexed: 01/28/2023] Open
Abstract
Glucose is the primary source of energy and a key substrate for most cells. Inhibition of cellular glucose uptake (the first step in its utilization) has, therefore, received attention as a potential therapeutic strategy to treat various unrelated diseases including malaria and cancers. For malaria, blood forms of parasites rely almost entirely on glycolysis for energy production and, without energy stores, they are dependent on the constant uptake of glucose. Plasmodium falciparum is the most dangerous human malarial parasite and its hexose transporter has been identified as being the major glucose transporter. In this review, recent progress regarding the validation and development of the P. falciparum hexose transporter as a drug target is described, highlighting the importance of robust target validation through both chemical and genetic methods. Therapeutic targeting potential of hexose transporters of other protozoan pathogens is also reviewed and discussed.
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Affiliation(s)
- Ksenija Slavic
- Centre for Infection, Division of Cellular and Molecular Medicine, St. George's, University of London, Cranmer Terrace, London SW17 0RE, UK.
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41
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Blume M, Hliscs M, Rodriguez-Contreras D, Sanchez M, Landfear S, Lucius R, Matuschewski K, Gupta N. A constitutive pan-hexose permease for the Plasmodium life cycle and transgenic models for screening of antimalarial sugar analogs. FASEB J 2010; 25:1218-29. [PMID: 21169382 DOI: 10.1096/fj.10-173278] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Glucose is considered essential for erythrocytic stages of the malaria parasite, Plasmodium falciparum. Importance of sugar and its permease for hepatic and sexual stages of Plasmodium, however, remains elusive. Moreover, increasing global resistance to current antimalarials necessitates the search for novel drugs. Here, we reveal that hexose transporter 1 (HT1) of Plasmodium berghei can transport glucose (K(m)~87 μM), mannose (K(i)~93 μM), fructose (K(i)~0.54 mM), and galactose (K(i)~5 mM) in Leishmania mexicana mutant and Xenopus laevis; and, therefore, is functionally equivalent to HT1 of P. falciparum (Glc, K(m)~175 μM; Man, K(i)~276 μM; Fru, K(i)~1.25 mM; Gal, K(i)~5.86 mM). Notably, a glucose analog, C3361, attenuated hepatic (IC(50)~15 μM) and ookinete development of P. berghei. The PbHT1 could be ablated during intraerythrocytic stages only by concurrent complementation with PbHT1-HA or PfHT1. Together; these results signify that PbHT1 and glucose are required for the entire life cycle of P. berghei. Accordingly, PbHT1 is expressed in the plasma membrane during all parasite stages. To permit a high-throughput screening of PfHT1 inhibitors and their subsequent in vivo assessment, we have generated Saccharomyces cerevisiae mutant expressing codon-optimized PfHT1, and a PfHT1-dependent Δpbht1 parasite strain. This work provides a platform to facilitate the development of drugs against malaria, and it suggests a disease-control aspect by reducing parasite transmission.
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Affiliation(s)
- Martin Blume
- Department of Molecular Parasitology, Humboldt University, Berlin, Germany
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42
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Olszewski KL, Llinás M. Central carbon metabolism of Plasmodium parasites. Mol Biochem Parasitol 2010; 175:95-103. [PMID: 20849882 DOI: 10.1016/j.molbiopara.2010.09.001] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2010] [Revised: 09/01/2010] [Accepted: 09/02/2010] [Indexed: 12/22/2022]
Abstract
The central role of metabolic perturbation to the pathology of malaria, the promise of antimetabolites as antimalarial drugs and a basic scientific interest in understanding this fascinating example of highly divergent microbial metabolism has spurred a major and concerted research effort towards elucidating the metabolic network of the Plasmodium parasites. Central carbon metabolism, broadly comprising the flow of carbon from nutrients into biomass, has been a particular focus due to clear and early indications that it plays an essential role in this network. Decades of painstaking efforts have significantly clarified our understanding of these pathways of carbon flux, and this foundational knowledge, coupled with the advent of advanced analytical technologies, have set the stage for the development of a holistic, network-level model of plasmodial carbon metabolism. In this review we summarize the current state of knowledge regarding central carbon metabolism and suggest future avenues of research. We focus primarily on the blood stages of Plasmodium falciparum, the most lethal of the human malaria parasites, but also integrate results from simian, avian and rodent models of malaria that were a major focus of early investigations into plasmodial metabolism.
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Affiliation(s)
- Kellen L Olszewski
- Department of Molecular Biology & Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544, USA
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43
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Maughan SC, Pasternak M, Cairns N, Kiddle G, Brach T, Jarvis R, Haas F, Nieuwland J, Lim B, Müller C, Salcedo-Sora E, Kruse C, Orsel M, Hell R, Miller AJ, Bray P, Foyer CH, Murray JAH, Meyer AJ, Cobbett CS. Plant homologs of the Plasmodium falciparum chloroquine-resistance transporter, PfCRT, are required for glutathione homeostasis and stress responses. Proc Natl Acad Sci U S A 2010; 107:2331-6. [PMID: 20080670 PMCID: PMC2836691 DOI: 10.1073/pnas.0913689107] [Citation(s) in RCA: 133] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
In Arabidopsis thaliana, biosynthesis of the essential thiol antioxidant, glutathione (GSH), is plastid-regulated, but many GSH functions, including heavy metal detoxification and plant defense activation, depend on cytosolic GSH. This finding suggests that plastid and cytosol thiol pools are closely integrated and we show that in Arabidopsis this integration requires a family of three plastid thiol transporters homologous to the Plasmodium falciparum chloroquine-resistance transporter, PfCRT. Arabidopsis mutants lacking these transporters are heavy metal-sensitive, GSH-deficient, and hypersensitive to Phytophthora infection, confirming a direct requirement for correct GSH homeostasis in defense responses. Compartment-specific measurements of the glutathione redox potential using redox-sensitive GFP showed that knockout of the entire transporter family resulted in a more oxidized glutathione redox potential in the cytosol, but not in the plastids, indicating the GSH-deficient phenotype is restricted to the cytosolic compartment. Expression of the transporters in Xenopus oocytes confirmed that each can mediate GSH uptake. We conclude that these transporters play a significant role in regulating GSH levels and the redox potential of the cytosol.
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Affiliation(s)
- Spencer C Maughan
- Institute of Biotechnology, University of Cambridge, Cambridge CB2 1QT, United Kingdom.
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44
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Müller IB, Knöckel J, Eschbach ML, Bergmann B, Walter RD, Wrenger C. Secretion of an acid phosphatase provides a possible mechanism to acquire host nutrients by Plasmodium falciparum. Cell Microbiol 2010; 12:677-91. [PMID: 20070315 DOI: 10.1111/j.1462-5822.2010.01426.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
As an intracellular proliferating parasite, Plasmodium falciparum exploits the human host to acquire nutrients. However, nutrients such as nucleotides and cofactors are mostly phosphorylated in the host cell cytosol and thus have to be dephosphorylated in order to be taken up by the parasite. Here we report the functional characterization of a unique secreted phosphatase in P. falciparum, which is expressed throughout the developmental stages in the red blood cell. We show that this enzyme, formerly described as anchoring glideosome-associated protein 50 (GAP50), reveals a broad substrate profile with preference for di- and triphosphates at pH 5-7. Bioinformatic studies of the protein sequence identified an N-terminal signal anchor (SA) as well as a C-terminal transmembrane domain. By means of live microscopy of parasites transfected with GFP-fusions of this secreted acid phosphatase (PfSAP), we demonstrate that PfSAP enters the secretory pathway en route to the parasite periphery - mediated by SA - and is subsequently engulfed into the food vacuole. We corroborate this with independent data where acid phosphatase activity is visualized in close proximity to hemozoin. The biochemical as well as the trafficking results support the proposed role of PfSAP in the acquisition of host nutrients by dephosphorylation.
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Affiliation(s)
- Ingrid B Müller
- Bernhard Nocht Institute for Tropical Medicine, Department of Biochemistry, Hamburg, Germany.
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45
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Abstract
Glucose and related hexoses play central roles in the biochemistry and metabolism of single-cell parasites such as Leishmania, Trypanosoma, and Plasmodium that are the causative agents of leishmaniasis, African sleeping sickness, and malaria. Glucose transporters and the genes that encode them have been identified in each of these parasites and their functional properties have been scrutinized. These transporters are related in sequence and structure to mammalian facilitative glucose transporters of the SLC2 family, but they are nonetheless quite divergent in sequence. Hexose transporters have been shown to be essential for the viability of the infectious stage of each of these parasites and thus may represent targets for development of novel anti-parasitic drugs. The study of these transporters also illuminates many aspects of the basic biology of Leishmania, trypanosomes, and malaria parasites.
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Slavic K, Derbyshire ET, Naftalin RJ, Krishna S, Staines HM. Comparison of effects of green tea catechins on apicomplexan hexose transporters and mammalian orthologues. Mol Biochem Parasitol 2009; 168:113-6. [PMID: 19577593 PMCID: PMC2791876 DOI: 10.1016/j.molbiopara.2009.06.008] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2009] [Revised: 05/17/2009] [Accepted: 06/25/2009] [Indexed: 12/01/2022]
Abstract
Here we have investigated the inhibitory properties of green tea catechins on the Plasmodium falciparum hexose transporter (PfHT), the Babesia bovis hexose transporter 1 (BboHT1) and the mammalian facilitative glucose transporters, GLUT1 and GLUT5, expressed in Xenopus laevis oocytes. (-)-Epicatechin-gallate (ECG) and (-)-epigallocatechin-gallate (EGCG) inhibited D-glucose transport by GLUT1 and PfHT, and D-fructose transport by GLUT5, with apparent K(i) values between 45 and 117 microM. BboHT1 was more potently inhibited by the ungallated catechins (-)-epicatechin (EC) and (-)-epigallocatechin (EGC), with apparent K(i) values of 108 and 168 microM, respectively. Site-directed mutagenesis experiments provided little further support for previously reported models of catechin binding to hexose transporters. Furthermore, P. falciparum growth inhibition by catechins was not affected by the external D-glucose concentration. Our results provide new data on the inhibitory action of catechins against sugar transporters but were unable to elucidate the antimalarial mechanism of action of these agents.
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Affiliation(s)
- Ksenija Slavic
- Centre for Infection, Division of Cellular and Molecular Medicine, St. George's, University of London, Cranmer Terrace, London SW17 0RE, UK
| | - Elvira T. Derbyshire
- Centre for Infection, Division of Cellular and Molecular Medicine, St. George's, University of London, Cranmer Terrace, London SW17 0RE, UK
| | - Richard J. Naftalin
- Physiology, Franklin Wilkins Building, King's College London, Waterloo Campus, London SE1 9HN, UK
| | - Sanjeev Krishna
- Centre for Infection, Division of Cellular and Molecular Medicine, St. George's, University of London, Cranmer Terrace, London SW17 0RE, UK
| | - Henry M. Staines
- Centre for Infection, Division of Cellular and Molecular Medicine, St. George's, University of London, Cranmer Terrace, London SW17 0RE, UK
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47
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Identification, expression and characterisation of a Babesia bovis hexose transporter. Mol Biochem Parasitol 2008; 161:124-9. [PMID: 18638508 PMCID: PMC2688680 DOI: 10.1016/j.molbiopara.2008.06.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2008] [Revised: 06/18/2008] [Accepted: 06/19/2008] [Indexed: 11/21/2022]
Abstract
Babesia are tick-transmitted haemoprotozoan parasites that infect cattle, with an estimated 500 million at risk worldwide. Here, two predicted hexose transporters (BboHT1 and 2) have been identified within the Babesia bovis genome. BboHT1, having 40% and 47% amino acid sequence similarity compared with the human (GLUT1) and Plasmodium falciparum (PfHT) hexose transporters, respectively, is the only one that could be characterised functionally after expression in Xenopus laevis oocytes. Radiotracer studies on BboHT1 showed that it is a saturable, Na(+)-independent, stereo-specific hexose transporter, with a K(m) value for glucose of 0.84+/-0.54 mM (mean+/-SEM). Using D-glucose analogues, hydroxyl positions at O-4 and O-6 have been identified as important for ligand binding to BboHT1. D-glucose transport was inhibited maximally by cytochalasin B (50 microM). A long-chain O-3 hexose derivative (compound 3361) that selectively inhibits PfHT also inhibited relatively potently BboHT1, with an apparent K(i) value of 4.1+/-0.9 microM (mean+/-SEM). Compound 3361 did not inhibit B. bovis proliferation in in vitro growth assays but inhibited invasion of glucose-depleted bovine erythrocytes. Taken together with results of inhibition studies with cytochalasin B and beta-glucogallin, these data provide new insights into glucose metabolism of erythrocytic-stage Babesia infections.
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48
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Hot, sweet and sticky: the glycobiology of Plasmodium falciparum. Trends Parasitol 2008; 24:210-8. [DOI: 10.1016/j.pt.2008.02.007] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2007] [Revised: 02/02/2008] [Accepted: 02/05/2008] [Indexed: 11/22/2022]
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49
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Otake K, Suzuki H, Higashi R, Yabuuchi H, Haga M, Maeda T, Cook TJ, Tamai I. Improved Intestinal Membrane Permeability of Hexose-Quinoline Derivatives via the Hexose Transporter, SGLT1. J Pharm Sci 2008; 97:1821-30. [PMID: 17828732 DOI: 10.1002/jps.21147] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Intestinal membrane permeability is an important factor affecting the bioavailability of drugs. As a strategy to improve membrane permeability, membrane transporters are useful targets since essential nutrients are absorbed efficiently via specific transporters. For example, there are reports that intestinal hexose transporters could be used as a tool to improve permeability; however, there has been no direct evidence that the transporter protein, sodium/glucose cotransporter 1 (SGLT1), is involved in the transport of hexose analogs. Accordingly, we examined directly whether the intestinal membrane permeability of hexose analogs can be improved by utilizing SGLT1. Three hexose-quinoline derivatives were synthesized and their interactions with SGLT1 were evaluated. Among the three derivatives, the glucose-quinoline molecule exhibited an inhibitory effect on D-glucose uptake by both rat intestinal brush-border membrane vesicles (BBMVs) and Xenopus oocytes expressing SGLT1. In addition, significant uptake of the glucose-quinoline derivative by Xenopus oocytes expressing SGLT1 was observed by both an electrophysiological assay and direct measurement of the uptake of the compound, while the galactose-quinoline derivative did not show significant uptake via SGLT1. Thus, it was directly demonstrated that SGLT1 could be used as a tool for the improvement of intestinal membrane permeability of drugs by modification to the glucose analogs.
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Affiliation(s)
- Katsumasa Otake
- Faculty of Pharmaceutical Sciences, Tokyo University of Science, Noda, Chiba 278-8510, Japan
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50
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Patel AP, Staines HM, Krishna S. New antimalarial targets: the example of glucose transport. Travel Med Infect Dis 2008; 6:58-66. [PMID: 18342277 DOI: 10.1016/j.tmaid.2008.01.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2007] [Accepted: 01/10/2008] [Indexed: 11/19/2022]
Abstract
In order for a novel drug target to attract attention it must be shown to be essential for parasite survival. In addition, it is desirable that a novel target provides some molecular and functional basis for the development of selective inhibitors. In this respect the pathway for transport of glucose to the parasite in Plasmodium falciparum has attracted increasing interest as a target for antimalarial chemotherapy. In particular, the plasmodial hexose transporter, PfHT, known to mediate transport of this essential substrate to the parasite has been a promising candidate for development of inhibitors. The article summarises the steps involved in development of this parasite protein as a drug target. Details of PfHT identification, functional characterisation and its validation as a drug target by using a selective inhibitor are discussed. The potential use of a robust system to screen libraries of compounds in a high-throughput format, in pursuit of an inhibitor of PfHT is also described. In conclusion PfHT represents one example of a rational approach in the drug discovery process to structure-base design of drugs.
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Affiliation(s)
- Asha Parbhu Patel
- Centre for Infection, Division of Cellular and Molecular Medicine, St. George's, University of London, Cranmer Terrace, London SW17 0RE, UK.
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