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Buthelezi MN, Tshililo VG, Kappo AP, Simelane MBC. Phytochemical evaluation of Ziziphus mucronata and Xysmalobium undulutum towards the discovery and development of anti-malarial drugs. Malar J 2024; 23:141. [PMID: 38734650 PMCID: PMC11088772 DOI: 10.1186/s12936-024-04976-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Accepted: 05/04/2024] [Indexed: 05/13/2024] Open
Abstract
BACKGROUND The development of resistance by Plasmodium falciparum is a burdening hazard that continues to undermine the strides made to alleviate malaria. As such, there is an increasing need to find new alternative strategies. This study evaluated and validated 2 medicinal plants used in traditional medicine to treat malaria. METHODS Inspired by their ethnobotanical reputation of being effective against malaria, Ziziphus mucronata and Xysmalobium undulutum were collected and sequentially extracted using hexane (HEX), ethyl acetate (ETA), Dichloromethane (DCM) and methanol (MTL). The resulting crude extracts were screened for their anti-malarial and cytotoxic potential using the parasite lactate dehydrogenase (pLDH) and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, respectively. This was followed by isolating the active compounds from the DCM extract of Z. mucronata using silica gel chromatography and structural elucidation using spectroscopic techniques (NMR: 1H, 12C, and DEPT). The active compounds were then targeted against P. falciparum heat shock protein 70-1 (PfHsp70-1) using Autodock Vina, followed by in vitro validation assays using ultraviolet-visible (UV-VIS) spectroscopy and the malate dehydrogenase (MDH) chaperone activity assay. RESULTS The extracts except those of methanol displayed anti-malarial potential with varying IC50 values, Z. mucronata HEX (11.69 ± 3.84 µg/mL), ETA (7.25 ± 1.41 µg/mL), DCM (5.49 ± 0.03 µg/mL), and X. undulutum HEX (4.9 ± 0.037 µg/mL), ETA (17.46 ± 0.024 µg/mL) and DCM (19.27 ± 0.492 µg/mL). The extracts exhibited minimal cytotoxicity except for the ETA and DCM of Z. mucronata with CC50 values of 10.96 and 10.01 µg/mL, respectively. Isolation and structural characterization of the active compounds from the DCM extracts revealed that betulinic acid (19.95 ± 1.53 µg/mL) and lupeol (7.56 ± 2.03 µg/mL) were responsible for the anti-malarial activity and had no considerable cytotoxicity (CC50 > µg/mL). Molecular docking suggested strong binding between PfHsp70-1, betulinic acid (- 6.8 kcal/mol), and lupeol (- 6.9 kcal/mol). Meanwhile, the in vitro validation assays revealed the disruption of the protein structural elements and chaperone function. CONCLUSION This study proves that X undulutum and Z. mucronata have anti-malarial potential and that betulinic acid and lupeol are responsible for the activity seen on Z. mucronata. They also make a case for guided purification of new phytochemicals in the other extracts and support the notion of considering medicinal plants to discover new anti-malarials.
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Affiliation(s)
- Muzi N Buthelezi
- Department of Biochemistry, Faculty of Science, University of Johannesburg, Auckland Park Kingsway Campus, Johannesburg, South Africa
| | - Vhahangwele G Tshililo
- Department of Biochemistry, Faculty of Science, University of Johannesburg, Auckland Park Kingsway Campus, Johannesburg, South Africa
| | - Abidemi P Kappo
- Department of Biochemistry, Faculty of Science, University of Johannesburg, Auckland Park Kingsway Campus, Johannesburg, South Africa
| | - Mthokozisi B C Simelane
- Department of Biochemistry, Faculty of Science, University of Johannesburg, Auckland Park Kingsway Campus, Johannesburg, South Africa.
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Vaaltyn MC, Mateos‐Jimenez M, Müller R, Mackay CL, Edkins AL, Clarke DJ, Veale CGL. Native Mass Spectrometry-Guided Screening Identifies Hit Fragments for HOP-HSP90 PPI Inhibition. Chembiochem 2022; 23:e202200322. [PMID: 36017658 PMCID: PMC9826382 DOI: 10.1002/cbic.202200322] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Revised: 08/25/2022] [Indexed: 01/11/2023]
Abstract
Contemporary medicinal chemistry considers fragment-based drug discovery (FBDD) and inhibition of protein-protein interactions (PPI) as important means of expanding the volume of druggable chemical space. However, the ability to robustly identify valid fragments and PPI inhibitors is an enormous challenge, requiring the application of sensitive biophysical methodology. Accordingly, in this study, we exploited the speed and sensitivity of nanoelectrospray (nano-ESI) native mass spectrometry to identify a small collection of fragments which bind to the TPR2AB domain of HOP. Follow-up biophysical assessment of a small selection of binding fragments confirmed binding to the single TPR2A domain, and that this binding translated into PPI inhibitory activity between TPR2A and the HSP90 C-terminal domain. An in-silico assessment of binding fragments at the PPI interfacial region, provided valuable structural insight for future fragment elaboration strategies, including the identification of losartan as a weak, albeit dose-dependent inhibitor of the target PPI.
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Affiliation(s)
- Michaelone C. Vaaltyn
- The Biomedical Biotechnology Research Unit (BioBRU) Department of Biochemistry and Microbiology DepartmentRhodes UniversityMakhanda6139South Africa
| | - Maria Mateos‐Jimenez
- EaStCHEM School of ChemistryJoseph Black Building, David Brewster RoadEdinburghEH93FJUK
| | - Ronel Müller
- School of Chemistry and PhysicsUniversity of KwaZulu-NatalScottsville3209South Africa
| | - C. Logan Mackay
- EaStCHEM School of ChemistryJoseph Black Building, David Brewster RoadEdinburghEH93FJUK
| | - Adrienne L. Edkins
- The Biomedical Biotechnology Research Unit (BioBRU) Department of Biochemistry and Microbiology DepartmentRhodes UniversityMakhanda6139South Africa
| | - David J. Clarke
- EaStCHEM School of ChemistryJoseph Black Building, David Brewster RoadEdinburghEH93FJUK
| | - Clinton G. L. Veale
- Department of ChemistryUniversity of Cape Town RondeboschCape Town7700South Africa
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Muthelo T, Mulaudzi V, Netshishivhe M, Dongola TH, Kok M, Makumire S, de Villiers M, Burger A, Zininga T, Shonhai A. Inhibition of Plasmodium falciparum Hsp70-Hop partnership by 2-phenylthynesulfonamide. Front Mol Biosci 2022; 9:947203. [PMID: 36177352 PMCID: PMC9513230 DOI: 10.3389/fmolb.2022.947203] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Accepted: 08/29/2022] [Indexed: 11/13/2022] Open
Abstract
Plasmodium falciparum Hsp70-1 (PfHsp70-1; PF3D7_0818900) and PfHsp90 (PF3D7_0708400) are essential cytosol localized chaperones of the malaria parasite. The two chaperones form a functional complex via the adaptor protein, Hsp90-Hsp70 organizing protein (PfHop [PF3D7_1434300]), which modulates the interaction of PfHsp70-1 and PfHsp90 through its tetracopeptide repeat (TPR) domains in a nucleotide-dependent fashion. On the other hand, PfHsp70-1 and PfHsp90 possess C-terminal EEVD and MEEVD motifs, respectively, which are crucial for their interaction with PfHop. By coordinating the cooperation of these two chaperones, PfHop plays an important role in the survival of the malaria parasite. 2-Phenylthynesulfonamide (PES) is a known anti-cancer agent whose mode of action is to inhibit Hsp70 function. In the current study, we explored the antiplasmodial activity of PES and investigated its capability to target the functions of PfHsp70-1 and its co-chaperone, PfHop. PES exhibited modest antiplasmodial activity (IC50 of 38.7 ± 0.7 µM). Furthermore, using surface plasmon resonance (SPR) analysis, we demonstrated that PES was capable of binding recombinant forms of both PfHsp70-1 and PfHop. Using limited proteolysis and intrinsic fluorescence-based analysis, we showed that PES induces conformational changes in PfHsp70-1 and PfHop. In addition, we demonstrated that PES inhibits the chaperone function of PfHsp70-1. Consequently, PES abrogated the association of the two proteins in vitro. Our study findings contribute to the growing efforts to expand the arsenal of potential antimalarial compounds in the wake of growing parasite resistance against currently used drugs.
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Affiliation(s)
- Tshifhiwa Muthelo
- Department of Biochemistry & Microbiology, University of Venda, Thohoyandou, South Africa
| | - Vhahangwele Mulaudzi
- Department of Biochemistry & Microbiology, University of Venda, Thohoyandou, South Africa
| | - Munei Netshishivhe
- Department of Biochemistry & Microbiology, University of Venda, Thohoyandou, South Africa
| | | | - Michelle Kok
- Department of Biochemistry, Stellenbosch University, Matieland, South Africa
| | - Stanley Makumire
- Department of Biochemistry & Microbiology, University of Venda, Thohoyandou, South Africa
- Structural Biology Research Unit, Department of Integrative Biomedical Sciences, University of Cape Town, Cape Town, South Africa
| | | | - Adélle Burger
- Department of Biochemistry & Microbiology, University of Venda, Thohoyandou, South Africa
| | - Tawanda Zininga
- Department of Biochemistry & Microbiology, University of Venda, Thohoyandou, South Africa
- Department of Biochemistry, Stellenbosch University, Matieland, South Africa
| | - Addmore Shonhai
- Department of Biochemistry & Microbiology, University of Venda, Thohoyandou, South Africa
- *Correspondence: Addmore Shonhai,
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Hsp90 and Associated Co-Chaperones of the Malaria Parasite. Biomolecules 2022; 12:biom12081018. [PMID: 35892329 PMCID: PMC9332011 DOI: 10.3390/biom12081018] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2022] [Revised: 07/16/2022] [Accepted: 07/17/2022] [Indexed: 12/14/2022] Open
Abstract
Heat shock protein 90 (Hsp90) is one of the major guardians of cellular protein homeostasis, through its specialized molecular chaperone properties. While Hsp90 has been extensively studied in many prokaryotic and higher eukaryotic model organisms, its structural, functional, and biological properties in parasitic protozoans are less well defined. Hsp90 collaborates with a wide range of co-chaperones that fine-tune its protein folding pathway. Co-chaperones play many roles in the regulation of Hsp90, including selective targeting of client proteins, and the modulation of its ATPase activity, conformational changes, and post-translational modifications. Plasmodium falciparum is responsible for the most lethal form of human malaria. The survival of the malaria parasite inside the host and the vector depends on the action of molecular chaperones. The major cytosolic P. falciparum Hsp90 (PfHsp90) is known to play an essential role in the development of the parasite, particularly during the intra-erythrocytic stage in the human host. Although PfHsp90 shares significant sequence and structural similarity with human Hsp90, it has several major structural and functional differences. Furthermore, its co-chaperone network appears to be substantially different to that of the human host, with the potential absence of a key homolog. Indeed, PfHsp90 and its interface with co-chaperones represent potential drug targets for antimalarial drug discovery. In this review, we critically summarize the current understanding of the properties of Hsp90, and the associated co-chaperones of the malaria parasite.
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Stofberg ML, Caillet C, de Villiers M, Zininga T. Inhibitors of the Plasmodium falciparum Hsp90 towards Selective Antimalarial Drug Design: The Past, Present and Future. Cells 2021; 10:2849. [PMID: 34831072 PMCID: PMC8616389 DOI: 10.3390/cells10112849] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 10/14/2021] [Accepted: 10/15/2021] [Indexed: 12/12/2022] Open
Abstract
Malaria is still one of the major killer parasitic diseases in tropical settings, posing a public health threat. The development of antimalarial drug resistance is reversing the gains made in attempts to control the disease. The parasite leads a complex life cycle that has adapted to outwit almost all known antimalarial drugs to date, including the first line of treatment, artesunate. There is a high unmet need to develop new strategies and identify novel therapeutics to reverse antimalarial drug resistance development. Among the strategies, here we focus and discuss the merits of the development of antimalarials targeting the Heat shock protein 90 (Hsp90) due to the central role it plays in protein quality control.
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Affiliation(s)
| | | | | | - Tawanda Zininga
- Department of Biochemistry, Stellenbosch University, Stellenbosch 7600, South Africa; (M.L.S.); (C.C.); (M.d.V.)
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The Role of Hsp70s in the Development and Pathogenicity of Plasmodium falciparum. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021. [PMID: 34569021 DOI: 10.1007/978-3-030-78397-6_3] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/24/2024]
Abstract
The main agent of human malaria, the protozoa, Plasmodium falciparum is known to infect liver cells, subsequently invading the host erythrocyte, leading to the manifestation of clinical outcomes of the disease. As part of its survival in the human host, P. falciparum employs several heat shock protein (Hsp) families whose primary purpose is to ensure cytoprotection through their molecular chaperone role. The parasite expresses six Hsp70s that localise to various subcellular organelles of the parasite, with one, PfHsp70-x, being exported to the infected human erythrocyte. The role of these Hsp70s in the survival and pathogenicity of malaria has received immense research attention. Several studies have reported on their structure-function features, network partnerships, and elucidation of their potential substrates. Apart from their role in cytoprotection and pathogenicity, Hsp70s are implicated in antimalarial drug resistance. As such, they are deemed potential antimalarial drug candidates, especially suited for co-targeting in combination therapies. In addition, Hsp70 is implicated in host immune modulation. The current report highlights the various structure-function features of these proteins, their roles in the development of malaria, current and prospective efforts being employed towards targeting them in malaria intervention efforts.
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Burger A, Macucule-Tinga P, Bentley SJ, Ludewig MH, Mhlongo NN, Shonhai A, Boshoff A. Characterization of an Atypical Trypanosoma brucei Hsp70 Demonstrates Its Cytosolic-Nuclear Localization and Modulation by Quercetin and Methylene Blue. Int J Mol Sci 2021; 22:ijms22136776. [PMID: 34202520 PMCID: PMC8269394 DOI: 10.3390/ijms22136776] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 06/01/2021] [Accepted: 06/08/2021] [Indexed: 11/16/2022] Open
Abstract
Trypanosoma brucei (Tb) harbours twelve Hsp70 chaperones. Of these, four are predicted to reside in the parasite cytosol. TbHsp70.c is predicted to be cytosolic and upregulated upon heat stress and is an ATPase that exhibits holdase chaperone function. Cytosol-localized Tbj2 stimulates the ATPase activity of TbHsp70.c. In the current study, immunofluorescence confirmed that TbHsp70.c is both a cytosolic and a nuclear protein. Furthermore, in silico analysis was used to elucidate an atypical linker and hydrophobic pocket. Tellingly, TbHsp70.c lacks the EEVD and GGMP motifs, both of which are implicated in substrate selectivity and co-chaperone binding in canonical Hsp70s. Far western analysis revealed that TbSTi1 interacts directly with TbHsp70 and TbHsp70.4, but does not bind TbHsp70.c. We further investigated the effect of quercetin and methylene blue on the Tbj2-driven ATPase activity of TbHsp70.c. We established that quercetin inhibited, whilst methylene blue enhanced, the Tbj2-stimulated ATPase activity of TbHsp70.c. Furthermore, these inhibitors were lethal to parasites. Lastly, we used molecular docking to show that quercetin and methylene blue may bind the nucleotide binding pocket of TbHsp70.c. Our findings suggest that small molecule inhibitors that target TbHsp70.c could be developed to serve as possible drug candidates against T. brucei.
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Affiliation(s)
- Adélle Burger
- Department of Biochemistry, University of Venda, Private Bag X5050, Thohoyandou 0950, South Africa;
- Correspondence: (A.B.); (A.B.); Tel.: +27-(0)-15-962-8620 (A.B.); +27-(0)-46-603-8630 (A.B.)
| | - Paula Macucule-Tinga
- Biotechnology Innovation Centre, Faculty of Science, Rhodes University, PO Box 94, Makhanda/Grahamstown 6140, South Africa; (P.M.-T.); (S.J.B.); (M.H.L.)
| | - Stephen John Bentley
- Biotechnology Innovation Centre, Faculty of Science, Rhodes University, PO Box 94, Makhanda/Grahamstown 6140, South Africa; (P.M.-T.); (S.J.B.); (M.H.L.)
| | - Michael Hans Ludewig
- Biotechnology Innovation Centre, Faculty of Science, Rhodes University, PO Box 94, Makhanda/Grahamstown 6140, South Africa; (P.M.-T.); (S.J.B.); (M.H.L.)
| | - Ndumiso Nhlakanipho Mhlongo
- Department of Medical Biochemistry, University of KwaZulu-Natal, Private Bag X54001, Durban 4000, South Africa;
| | - Addmore Shonhai
- Department of Biochemistry, University of Venda, Private Bag X5050, Thohoyandou 0950, South Africa;
| | - Aileen Boshoff
- Biotechnology Innovation Centre, Faculty of Science, Rhodes University, PO Box 94, Makhanda/Grahamstown 6140, South Africa; (P.M.-T.); (S.J.B.); (M.H.L.)
- Correspondence: (A.B.); (A.B.); Tel.: +27-(0)-15-962-8620 (A.B.); +27-(0)-46-603-8630 (A.B.)
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Abstract
It gives me great pleasure to have the opportunity to introduce myself to the readers of Biophysical Reviews as part of the 'meet the editors' series. What follows is a mini-autobiography of my life as it relates to my scientific career and research.
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Affiliation(s)
- Addmore Shonhai
- Department of Biochemistry, University of Venda, Private Bag X5050, Thohoyandou, 0950 South Africa
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Makumire S, Dongola TH, Chakafana G, Tshikonwane L, Chauke CT, Maharaj T, Zininga T, Shonhai A. Mutation of GGMP Repeat Segments of Plasmodium falciparum Hsp70-1 Compromises Chaperone Function and Hop Co-Chaperone Binding. Int J Mol Sci 2021; 22:ijms22042226. [PMID: 33672387 PMCID: PMC7926355 DOI: 10.3390/ijms22042226] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Revised: 02/02/2021] [Accepted: 02/09/2021] [Indexed: 12/11/2022] Open
Abstract
Parasitic organisms especially those of the Apicomplexan phylum, harbour a cytosol localised canonical Hsp70 chaperone. One of the defining features of this protein is the presence of GGMP repeat residues sandwiched between α-helical lid and C-terminal EEVD motif. The role of the GGMP repeats of Hsp70s remains unknown. In the current study, we introduced GGMP mutations in the cytosol localised Hsp70-1 of Plasmodium falciparum (PfHsp70-1) and a chimeric protein (KPf), constituted by the ATPase domain of E. coli DnaK fused to the C-terminal substrate binding domain of PfHsp70-1. A complementation assay conducted using E. coli dnaK756 cells demonstrated that the GGMP motif was essential for chaperone function of the chimeric protein, KPf. Interestingly, insertion of GGMP motif of PfHsp70-1 into DnaK led to a lethal phenotype in E. coli dnaK756 cells exposed to elevated growth temperature. Using biochemical and biophysical assays, we established that the GGMP motif accounts for the elevated basal ATPase activity of PfHsp70-1. Furthermore, we demonstrated that this motif is important for interaction of the chaperone with peptide substrate and a co-chaperone, PfHop. Our findings suggest that the GGMP may account for both the specialised chaperone function and reportedly high catalytic efficiency of PfHsp70-1.
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Affiliation(s)
- Stanley Makumire
- Department of Biochemistry, University of Venda, Private Bag X5050, Thohoyandou 0950, South Africa; (S.M.); (T.H.D.); (G.C.); (L.T.); (C.T.C.); (T.Z.)
- Structural Biology Research Unit, Department of Integrative Biomedical Sciences, University of Cape Town, Observatory 7925, South Africa
| | - Tendamudzimu Harmfree Dongola
- Department of Biochemistry, University of Venda, Private Bag X5050, Thohoyandou 0950, South Africa; (S.M.); (T.H.D.); (G.C.); (L.T.); (C.T.C.); (T.Z.)
| | - Graham Chakafana
- Department of Biochemistry, University of Venda, Private Bag X5050, Thohoyandou 0950, South Africa; (S.M.); (T.H.D.); (G.C.); (L.T.); (C.T.C.); (T.Z.)
- Department of Medicine, University of Cape Town, Faculty of Health Sciences, Observatory, Cape Town 7925, South Africa
| | - Lufuno Tshikonwane
- Department of Biochemistry, University of Venda, Private Bag X5050, Thohoyandou 0950, South Africa; (S.M.); (T.H.D.); (G.C.); (L.T.); (C.T.C.); (T.Z.)
| | - Cecilia Tshikani Chauke
- Department of Biochemistry, University of Venda, Private Bag X5050, Thohoyandou 0950, South Africa; (S.M.); (T.H.D.); (G.C.); (L.T.); (C.T.C.); (T.Z.)
| | - Tarushai Maharaj
- Department of Biochemistry, Stellenbosch University, Stellenbosch 7600, South Africa;
| | - Tawanda Zininga
- Department of Biochemistry, University of Venda, Private Bag X5050, Thohoyandou 0950, South Africa; (S.M.); (T.H.D.); (G.C.); (L.T.); (C.T.C.); (T.Z.)
- Department of Biochemistry, Stellenbosch University, Stellenbosch 7600, South Africa;
| | - Addmore Shonhai
- Department of Biochemistry, University of Venda, Private Bag X5050, Thohoyandou 0950, South Africa; (S.M.); (T.H.D.); (G.C.); (L.T.); (C.T.C.); (T.Z.)
- Correspondence: ; Tel.: +27-15962-8723
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Shonhai A, Blatch GL. Heat Shock Proteins of Malaria: Highlights and Future Prospects. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1340:237-246. [PMID: 34569028 DOI: 10.1007/978-3-030-78397-6_10] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
The deadliest malaria parasite of humans, Plasmodium falciparum, is an obligate parasite that has had to develop mechanisms for survival under the unfavourable conditions it confronts within host cells. The chapters in the book "Heat Shock Proteins of Malaria" provide a critique of the evidence that heat shock proteins (Hsps) play a key role in the survival of P. falciparum in host cells. The role of the plasmodial Hsp arsenal is not limited to the protection of the parasite cell (largely through their role as molecular chaperones), as some of these proteins also promote the pathological development of malaria. This is largely due to the export of a large number of these proteins into the infected erythrocyte cytosol. Although P. falciparum erythrocyte membrane protein 1 (PfEMP1) is the main virulence factor for the malaria parasite, some of the exported plasmodial Hsps appear to augment parasite virulence. While this book largely delves into experimentally validated information on the role of Hsps in the development and pathogenicity of malaria, some of the information is based on hypotheses yet to be fully tested. Therefore, here we highlight what we know to be definite roles of plasmodial Hsps. Furthermore, we distill information that could provide practical insights on the options available for future research directions, including interventions against malaria that may target the role of Hsps in the development of the disease.
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Affiliation(s)
- Addmore Shonhai
- Department of Biochemistry, University of Venda, Thohoyandou, South Africa.
| | - Gregory L Blatch
- The Vice Chancellery, The University of Notre Dame Australia, Fremantle, WA, Australia. .,Biomedical Biotechnology Research Unit, Department of Biochemistry and Microbiology, Rhodes University, Grahamstown, South Africa. .,The Institute of Immunology and Infectious Diseases, Murdoch University, Murdoch, WA, Australia. .,Faculty of Health Sciences, Higher Colleges of Technology, Sharjah, United Arab Emirates.
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