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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] [What about the content of this article? (0)] [Affiliation(s)] [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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2
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Olivier T, Loots L, Kok M, de Villiers M, Reader J, Birkholtz LM, Arnott GE, de Villiers KA. Adsorption to the surface of hemozoin crystals: Structure-based design and synthesis of new amino-phenoxazine β-hematin inhibitors. ChemMedChem 2022; 17:e202200139. [PMID: 35385211 DOI: 10.1002/cmdc.202200139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Revised: 04/05/2022] [Indexed: 11/07/2022]
Abstract
In silico adsorption of eight antimalarials that inhibit β-hematin (synthetic hemozoin) formation identified a primary binding site on the (001) face, which accommodates inhibitors via formation of predominantly π-π interactions. A good correlation (r2 = 0.64, P = 0.017) between adsorption energies and the logarithm of β-hematin inhibitory activity was found for this face. Of 53 monocyclic, bicyclic and tricyclic scaffolds, the latter yielded the most favorable adsorption energies. Five new amino-phenoxazine compounds were pursued as β-hematin inhibitors based on adsorption behaviour. The 2-substituted phenoxazines show good to moderate β-hematin inhibitory activity (< 100 μM) and Plasmodium falciparum blood stage activity against the 3D7 strain. N1,N1-diethyl-N4-(10H-phenoxazin-2-yl)pentane-1,4-diamine (P2a) is the most promising hit with IC50 values of 4.7 ± 0.6 and 0.64 ± 0.05 μM, respectively. Adsorption energies are predictive of β-hematin inhibitory activity, and thus the in silico approach is a beneficial tool for structure-based development of new non-quinoline inhibitors.
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Affiliation(s)
- Tania Olivier
- Stellenbosch University Faculty of Science, Chemistry and Polymer Science, SOUTH AFRICA
| | - Leigh Loots
- Stellenbosch University Faculty of Science, Chemistry and Polymer Science, SOUTH AFRICA
| | - Michélle Kok
- Stellenbosch University Faculty of Science, Biochemistry, SOUTH AFRICA
| | | | - Janette Reader
- University of Pretoria, Biochemistry, Genetics and Microbiology, SOUTH AFRICA
| | - Lyn-Marié Birkholtz
- University of Pretoria, Biochemistry, Genetics and Microbiology, SOUTH AFRICA
| | - Gareth E Arnott
- Stellenbosch University Faculty of Science, Chemistry and Polymer Science, 49 Almond Drive, Helderberg Estate, 7130, Somerset West, SOUTH AFRICA
| | - Katherine A de Villiers
- Stellenbosch University Faculty of Science, Chemistry and Polymer Science, Merriman Avenue, 7600, Stellenbosch, SOUTH AFRICA
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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4
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Spry C, Barnard L, Kok M, Powell AK, Mahesh D, Tjhin ET, Saliba KJ, Strauss E, de Villiers M. Toward a Stable and Potent Coenzyme A-Targeting Antiplasmodial Agent: Structure-Activity Relationship Studies of N-Phenethyl-α-methyl-pantothenamide. ACS Infect Dis 2020; 6:1844-1854. [PMID: 32375471 DOI: 10.1021/acsinfecdis.0c00075] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Pantothenamides (PanAms) are potent antiplasmodials with low human toxicity currently being investigated as antimalarials with a novel mode of action. These structural analogues of pantothenate, the vitamin precursor of the essential cofactor coenzyme A, are susceptible to degradation by pantetheinase enzymes present in serum. We previously discovered that α-methylation of the β-alanine moiety of PanAms increases their stability in serum and identified N-phenethyl-α-methyl-pantothenamide as a pantetheinase-resistant PanAm with potent, on-target, and selective antiplasmodial activity. In this study, we performed structure-activity relationship investigations to establish whether stability and potency can be improved further through alternative modification of the scissile amide bond and through substitution/modification of the phenyl ring. Additionally, for the first time, the importance of the stereochemistry of the α-methyl group was evaluated in terms of stability versus potency. Our results demonstrate that α-methylation remains the superior choice for amide modification, and that while monofluoro-substitution of the phenyl ring (that often improves ADME properties) was tolerated, N-phenethyl-α-methyl-pantothenamide remains the most potent analogue. We show that the 2S,2'R-diastereomer is far more potent than the 2R,2'R-diastereomer and that this cannot be attributed to preferential metabolic activation by pantothenate kinase, the first enzyme of the coenzyme A biosynthesis pathway. Unexpectedly, the more potent 2S,2'R-diastereomer is also more prone to pantetheinase-mediated degradation. Finally, the results of in vitro studies to assess permeability and metabolic stability of the 2S,2'R-diastereomer suggested species-dependent degradation via amide hydrolysis. Our study provides important information for the continued development of PanAm-based antimalarials.
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Affiliation(s)
| | - Leanne Barnard
- Department of Biochemistry, Stellenbosch University, Stellenbosch 7600, South Africa
| | - Michélle Kok
- Department of Biochemistry, Stellenbosch University, Stellenbosch 7600, South Africa
| | - Andrew K. Powell
- Centre for Drug Candidate Optimisation, Monash Institute of Pharmaceutical Sciences, 381 Royal Parade, Parkville, Victoria 3052, Australia
| | | | | | | | - Erick Strauss
- Department of Biochemistry, Stellenbosch University, Stellenbosch 7600, South Africa
| | - Marianne de Villiers
- Department of Biochemistry, Stellenbosch University, Stellenbosch 7600, South Africa
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Di Meo I, Colombelli C, Srinivasan B, de Villiers M, Hamada J, Jeong SY, Fox R, Woltjer RL, Tepper PG, Lahaye LL, Rizzetto E, Harrs CH, de Boer T, van der Zwaag M, Jenko B, Čusak A, Pahor J, Kosec G, Grzeschik NA, Hayflick SJ, Tiranti V, Sibon OCM. Acetyl-4'-phosphopantetheine is stable in serum and prevents phenotypes induced by pantothenate kinase deficiency. Sci Rep 2017; 7:11260. [PMID: 28900161 PMCID: PMC5595861 DOI: 10.1038/s41598-017-11564-8] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Accepted: 08/09/2017] [Indexed: 01/22/2023] Open
Abstract
Coenzyme A is an essential metabolite known for its central role in over one hundred cellular metabolic reactions. In cells, Coenzyme A is synthesized de novo in five enzymatic steps with vitamin B5 as the starting metabolite, phosphorylated by pantothenate kinase. Mutations in the pantothenate kinase 2 gene cause a severe form of neurodegeneration for which no treatment is available. One therapeutic strategy is to generate Coenzyme A precursors downstream of the defective step in the pathway. Here we describe the synthesis, characteristics and in vivo rescue potential of the acetyl-Coenzyme A precursor S-acetyl-4′-phosphopantetheine as a possible treatment for neurodegeneration associated with pantothenate kinase deficiency.
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Affiliation(s)
- Ivano Di Meo
- Division of Molecular Neurogenetics, IRCCS Foundation Neurological Institute "C.Besta" Via Temolo 4, 20126, Milano, Italy
| | - Cristina Colombelli
- Division of Molecular Neurogenetics, IRCCS Foundation Neurological Institute "C.Besta" Via Temolo 4, 20126, Milano, Italy
| | - Balaji Srinivasan
- Department of Cell Biology, University Medical Center Groningen, University of Groningen, Ant. Deusinglaan 1, 9713 AV, Groningen, The Netherlands
| | - Marianne de Villiers
- Department of Biochemistry, Stellenbosch University, Stellenbosch, 7600, South Africa
| | - Jeffrey Hamada
- Departments of Molecular & Medical Genetics and Pathology, Oregon Health & Science University, Portland, OR, 97239, USA
| | - Suh Y Jeong
- Departments of Molecular & Medical Genetics and Pathology, Oregon Health & Science University, Portland, OR, 97239, USA
| | - Rachel Fox
- Departments of Molecular & Medical Genetics and Pathology, Oregon Health & Science University, Portland, OR, 97239, USA
| | - Randall L Woltjer
- Departments of Molecular & Medical Genetics and Pathology, Oregon Health & Science University, Portland, OR, 97239, USA
| | - Pieter G Tepper
- Department of Chemical and Pharmaceutical Biology, University of Groningen, Ant. Deusinglaan 1, 9713 AV, Groningen, The Netherlands
| | - Liza L Lahaye
- Department of Cell Biology, University Medical Center Groningen, University of Groningen, Ant. Deusinglaan 1, 9713 AV, Groningen, The Netherlands
| | - Emanuela Rizzetto
- Clinical Pathology and Medical Genetics Unit, Foundation IRCCS-Neurological Institute "Carlo Besta", Milano, Italy
| | - Clara H Harrs
- Department of Cell Biology, University Medical Center Groningen, University of Groningen, Ant. Deusinglaan 1, 9713 AV, Groningen, The Netherlands
| | - Theo de Boer
- Analytical Biochemical Laboratory (ABL), WA Scholtenstraat 7, 9403 AJ, Assen, The Netherlands
| | - Marianne van der Zwaag
- Department of Cell Biology, University Medical Center Groningen, University of Groningen, Ant. Deusinglaan 1, 9713 AV, Groningen, The Netherlands
| | - Branko Jenko
- Acies Bio d.o.o., Tehnološki park 21, 1000, Ljubljana, Slovenia
| | - Alen Čusak
- Acies Bio d.o.o., Tehnološki park 21, 1000, Ljubljana, Slovenia
| | - Jerca Pahor
- Acies Bio d.o.o., Tehnološki park 21, 1000, Ljubljana, Slovenia.,Laboratory of Organic and Bioorganic Chemistry, Department of Physical and Organic Chemistry, Jožef Stefan Institute, Jamova 39, 1000, Ljubljana, Slovenia
| | - Gregor Kosec
- Acies Bio d.o.o., Tehnološki park 21, 1000, Ljubljana, Slovenia
| | - Nicola A Grzeschik
- Department of Cell Biology, University Medical Center Groningen, University of Groningen, Ant. Deusinglaan 1, 9713 AV, Groningen, The Netherlands
| | - Susan J Hayflick
- Departments of Molecular & Medical Genetics and Pathology, Oregon Health & Science University, Portland, OR, 97239, USA
| | - Valeria Tiranti
- Division of Molecular Neurogenetics, IRCCS Foundation Neurological Institute "C.Besta" Via Temolo 4, 20126, Milano, Italy
| | - Ody C M Sibon
- Department of Cell Biology, University Medical Center Groningen, University of Groningen, Ant. Deusinglaan 1, 9713 AV, Groningen, The Netherlands.
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6
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de Villiers M, Spry C, Macuamule CJ, Barnard L, Wells G, Saliba KJ, Strauss E. Antiplasmodial Mode of Action of Pantothenamides: Pantothenate Kinase Serves as a Metabolic Activator Not as a Target. ACS Infect Dis 2017; 3:527-541. [PMID: 28437604 DOI: 10.1021/acsinfecdis.7b00024] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
N-Substituted pantothenamides (PanAms) are pantothenate analogues with up to nanomolar potency against blood-stage Plasmodium falciparum (the most virulent species responsible for malaria). Although these compounds are known to target coenzyme A (CoA) biosynthesis and/or utilization, their exact mode of action (MoA) is still unknown. Importantly, PanAms that retain the natural β-alanine moiety are more potent than other variants, consistent with the involvement of processes that are selective for pantothenate (the precursor of CoA) or its derivatives. The transport of pantothenate and its phosphorylation by P. falciparum pantothenate kinase (PfPanK, the first enzyme of CoA biosynthesis) are two such processes previously highlighted as potential targets for the PanAms' antiplasmodial action. In this study, we investigated the effect of PanAms on these processes using their radiolabeled versions (synthesized here for the first time), which made possible the direct measurement of PanAm uptake by isolated blood-stage parasites and PanAm phosphorylation by PfPanK present in parasite lysates. We found that the MoA of PanAms does not involve interference with pantothenate transport and that inhibition of PfPanK-mediated pantothenate phosphorylation does not correlate with PanAm antiplasmodial activity. Instead, PanAms that retain the β-alanine moiety were found to be metabolically activated by PfPanK in a selective manner, forming phosphorylated products that likely inhibit other steps in CoA biosynthesis or are transformed into CoA antimetabolites that can interfere with CoA utilization. These findings provide direction for the ongoing development of CoA-targeted inhibitors as antiplasmodial agents with clinical potential.
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Affiliation(s)
- Marianne de Villiers
- Department of Biochemistry, Stellenbosch University, Stellenbosch 7600, South Africa
| | | | | | - Leanne Barnard
- Department of Biochemistry, Stellenbosch University, Stellenbosch 7600, South Africa
| | - Gordon Wells
- Department of Biochemistry, Stellenbosch University, Stellenbosch 7600, South Africa
| | | | - Erick Strauss
- Department of Biochemistry, Stellenbosch University, Stellenbosch 7600, South Africa
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7
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Affiliation(s)
| | - Erick Strauss
- Department of Biochemistry, Stellenbosch University, Stellenbosch, South Africa
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8
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de Villiers J, de Villiers M, Geertsema EM, Raj H, Poelarends GJ. Chemoenzymatic Synthesis of ortho-, meta-, and para-Substituted Derivatives of l- threo-3-Benzyloxyaspartate, An Important Glutamate Transporter Blocker. ChemCatChem 2015; 7:1931-1934. [PMID: 26251674 PMCID: PMC4517298 DOI: 10.1002/cctc.201500318] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2015] [Indexed: 01/13/2023]
Abstract
A simple, three-step chemoenzymatic synthesis of l-threo-3-benzyloxyaspartate (l-TBOA), as well as l-TBOA derivatives with F, CF3, and CH3 substituents at the aromatic ring, starting from dimethyl acetylenedicarboxylate was investigated. These chiral amino acids, which are extremely difficult to prepare by chemical synthesis, form an important class of inhibitors of excitatory amino acid transporters involved in the regulation of glutamatergic neurotransmission. In addition, a new chemical procedure for the synthesis of racemic mixtures of TBOA and its derivatives was explored. These chemically prepared racemates are valuable reference compounds in chiral-phase HPLC to establish the enantiopurities of the corresponding chemoenzymatically prepared amino acids.
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Affiliation(s)
- Jandré de Villiers
- Department of Pharmaceutical Biology, Groningen Research Institute of Pharmacy University of Groningen, Antonius Deusinglaan 1, 9713 AV Groningen (The Netherlands )
| | - Marianne de Villiers
- Department of Pharmaceutical Biology, Groningen Research Institute of Pharmacy University of Groningen, Antonius Deusinglaan 1, 9713 AV Groningen (The Netherlands )
| | - Edzard M Geertsema
- Department of Pharmaceutical Biology, Groningen Research Institute of Pharmacy University of Groningen, Antonius Deusinglaan 1, 9713 AV Groningen (The Netherlands )
| | - Hans Raj
- Department of Pharmaceutical Biology, Groningen Research Institute of Pharmacy University of Groningen, Antonius Deusinglaan 1, 9713 AV Groningen (The Netherlands ) ; Current address: Chr-Hansen A/S, Boge Alle 10-12 2970 Horsholm (Denmark)
| | - Gerrit J Poelarends
- Department of Pharmaceutical Biology, Groningen Research Institute of Pharmacy University of Groningen, Antonius Deusinglaan 1, 9713 AV Groningen (The Netherlands )
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9
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de Villiers M, Barnard L, Koekemoer L, Snoep JL, Strauss E. Variation in pantothenate kinase type determines the pantothenamide mode of action and impacts on coenzyme A salvage biosynthesis. FEBS J 2014; 281:4731-53. [PMID: 25156889 DOI: 10.1111/febs.13013] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2014] [Revised: 07/18/2014] [Accepted: 08/18/2014] [Indexed: 11/28/2022]
Abstract
N-substituted pantothenamides are analogues of pantothenic acid, the vitamin precursor of CoA, and constitute a class of well-studied bacterial growth inhibitors that show potential as new antibacterial agents. Previous studies have highlighted the importance of pantothenate kinase (PanK; EC 2.7.1.33) (the first enzyme of CoA biosynthesis) in mediating pantothenamide-induced growth inhibition by one of two proposed mechanisms: first, by acting on the pantothenamides as alternate substrates (allowing their conversion into CoA antimetabolites, with subsequent effects on CoA- and acyl carrier protein-dependent processes) or, second, by being directly inhibited by them (causing a reduction in CoA biosynthesis). In the present study we used structurally modified pantothenamides to probe whether PanKs interact with these compounds in the same manner. We show that the three distinct types of eubacterial PanKs that are known to exist (PanKI , PanKII and PanKIII ) respond very differently and, consequently, are responsible for determining the pantothenamide mode of action in each case: although the promiscuous PanKI enzymes accept them as substrates, the highly selective PanKIII s are resistant to their inhibitory effects. Most unexpectedly, Staphylococcus aureus PanK (the only known example of a bacterial PanKII ) experiences uncompetitive inhibition in a manner that is described for the first time. In addition, we show that pantetheine, a CoA degradation product that closely resembles the pantothenamides, causes the same effect. This suggests that, in S. aureus, pantothenamides may act by usurping a previously unknown role of pantetheine in the regulation of CoA biosynthesis, and validates its PanK as a target for the development of new antistaphylococcal agents.
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de Villiers M, Macuamule C, Spry C, Hyun YM, Strauss E, Saliba KJ. Structural modification of pantothenamides counteracts degradation by pantetheinase and improves antiplasmodial activity. ACS Med Chem Lett 2013; 4:784-9. [PMID: 24900746 DOI: 10.1021/ml400180d] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2013] [Accepted: 06/17/2013] [Indexed: 11/30/2022] Open
Abstract
Pantothenamides are secondary or tertiary amides of pantothenic acid, the vitamin precursor of the essential cofactor and universal acyl carrier coenzyme A. A recent study has demonstrated that pantothenamides inhibit the growth of blood-stage Plasmodium falciparum with submicromolar potency by exerting an effect on pantothenic acid utilization, but only when the pantetheinase present in the growth medium has been inactivated. Here, we demonstrate that small modifications of the pantothenamide core structure are sufficient to counteract pantetheinase-mediated degradation and that the resulting pantothenamide analogues still inhibit the in vitro proliferation of P. falciparum by targeting a pantothenic acid-dependent process (or processes). Finally, we investigated the toxicity of the most potent analogues to human cells and show that the selectivity ratio exceeds 100 in one case. Taken together, these results provide further support for pantothenic acid utilization being a viable target for antimalarial drug discovery.
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Affiliation(s)
- Marianne de Villiers
- Department of Biochemistry, Stellenbosch University, Stellenbosch 7600, South Africa
| | - Cristiano Macuamule
- Department of Biochemistry, Stellenbosch University, Stellenbosch 7600, South Africa
| | | | | | - Erick Strauss
- Department of Biochemistry, Stellenbosch University, Stellenbosch 7600, South Africa
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de Villiers M, Puthan Veetil V, Raj H, de Villiers J, Poelarends GJ. Catalytic mechanisms and biocatalytic applications of aspartate and methylaspartate ammonia lyases. ACS Chem Biol 2012; 7:1618-28. [PMID: 22834890 DOI: 10.1021/cb3002792] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Ammonia lyases catalyze the formation of α,β-unsaturated bonds by the elimination of ammonia from their substrates. This conceptually straightforward reaction has been the emphasis of many studies, with the main focus on the catalytic mechanism of these enzymes and/or the use of these enzymes as catalysts for the synthesis of enantiomerically pure α-amino acids. In this Review aspartate ammonia lyase and 3-methylaspartate ammonia lyase, which represent two different enzyme superfamilies, are discussed in detail. In the past few years, the three-dimensional structures of these lyases in complex with their natural substrates have revealed the details of two elegant catalytic strategies. These strategies exploit similar deamination mechanisms that involve general-base catalyzed formation of an enzyme-stabilized enolate anion (aci-carboxylate) intermediate. Recent progress in the engineering and application of these enzymes to prepare enantiopure l-aspartic acid derivatives, which are highly valuable as tools for biological research and as chiral building blocks for pharmaceuticals and food additives, is also discussed.
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Affiliation(s)
- Marianne de Villiers
- Department
of Pharmaceutical Biology, Groningen Research Institute of Pharmacy, University of Groningen, Antonius Deusinglaan 1, 9713
AV Groningen, The Netherlands
| | - Vinod Puthan Veetil
- Department
of Pharmaceutical Biology, Groningen Research Institute of Pharmacy, University of Groningen, Antonius Deusinglaan 1, 9713
AV Groningen, The Netherlands
| | - Hans Raj
- Department
of Pharmaceutical Biology, Groningen Research Institute of Pharmacy, University of Groningen, Antonius Deusinglaan 1, 9713
AV Groningen, The Netherlands
| | - Jandré de Villiers
- Department
of Pharmaceutical Biology, Groningen Research Institute of Pharmacy, University of Groningen, Antonius Deusinglaan 1, 9713
AV Groningen, The Netherlands
| | - Gerrit J. Poelarends
- Department
of Pharmaceutical Biology, Groningen Research Institute of Pharmacy, University of Groningen, Antonius Deusinglaan 1, 9713
AV Groningen, The Netherlands
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