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Pal C. Redox modulating small molecules having antimalarial efficacy. Biochem Pharmacol 2023; 218:115927. [PMID: 37992998 DOI: 10.1016/j.bcp.2023.115927] [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: 08/20/2023] [Revised: 11/13/2023] [Accepted: 11/14/2023] [Indexed: 11/24/2023]
Abstract
The search for effective antimalarial agents remains a critical priority because malaria is widely spread and drug-resistant strains are becoming more prevalent. In this review, a variety of small molecules capable of modulating redox processes were showcased for their potential as antimalarial agents. The compounds were designed to target the redox balance of Plasmodium parasites, which has a pivotal function in their ability to survive and multiply within the host organism. A thorough screening method was utilized to assess the effectiveness of these compounds against both drug-sensitive and drug-resistant strains of Plasmodium falciparum, the malaria-causing parasite. The results revealed that several of the tested compounds exhibited significant effectiveness against malaria, displaying IC50 values at a low micromolar range. Furthermore, these compounds displayed promising selectivity for the parasite, as they exhibited low cytotoxicity towards mammalian cells. Thorough mechanistic studies were undertaken to clarify how the active compounds exert their mode of action. The findings revealed that these compounds disrupted the parasites' redox balance, causing oxidative stress and interfering with essential cellular functions. Additionally, the compounds showed synergistic effects when combined with existing antimalarial drugs, suggesting their potential for combination therapies to combat drug resistance. Overall, this study highlights the potential of redox-modulating small molecules as effective antimalarial agents. The identified compounds demonstrate promising antimalarial activity, and their mechanism of action offers insights into targeting the redox balance of Plasmodium parasites. Further optimization and preclinical studies are warranted to determine their efficacy, safety, and potential for clinical development as novel antimalarial therapeutics.
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Affiliation(s)
- Chinmay Pal
- Department of Chemistry, Gobardanga Hindu College, North 24 Parganas, West Bengal 743273, India.
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2
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A review on the druggability of a thiol-based enzymatic antioxidant thioredoxin reductase for treating filariasis and other parasitic infections. Int J Biol Macromol 2020; 142:125-141. [DOI: 10.1016/j.ijbiomac.2019.09.083] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Revised: 09/10/2019] [Accepted: 09/11/2019] [Indexed: 01/07/2023]
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3
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Abhishek S, Sivadas S, Satish M, Deeksha W, Rajakumara E. Dynamic Basis for Auranofin Drug Recognition by Thiol-Reductases of Human Pathogens and Intermediate Coordinated Adduct Formation with Catalytic Cysteine Residues. ACS OMEGA 2019; 4:9593-9602. [PMID: 31460050 PMCID: PMC6649031 DOI: 10.1021/acsomega.9b00529] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Accepted: 05/14/2019] [Indexed: 05/13/2023]
Abstract
In all the living systems, reactive oxygen species (ROS) metabolism provides resistance against internal and external oxidative stresses. Auranofin (AF), an FDA-approved gold [Au(I)]-conjugated drug, is known to selectively target thiol-reductases, key enzymes involved in ROS metabolism. AF has been successfully tested for its inhibitory activity through biochemical studies, both in vitro and in vivo, against a diverse range of pathogens including protozoa, nematodes, bacteria, and so forth. Cocrystal structures of thiol-reductases complexed with AF revealed that Au(I) was coordinately linked to catalytic cysteines, but the mechanism of transfer of Au(I) from AF to catalytic cysteines still remains unknown. In this study, we have employed computational approaches to understand the interaction of AF with thiol-reductases of selected human pathogens. A similar network of interactions of AF was observed in all the studied enzymes. Also, we have shown that tailor-made analogues of AF can be designed against selective thiol-reductases for targeted inhibition. Molecular dynamics studies show that the AF-intermediates, tetraacetylthioglucose (TAG)-gold, and triethylphosphine (TP)-gold, coordinately linked to one of catalytic cysteines, remain stable in the binding pocket of thiol-reductases for Leishmania infantum and Plasmodium falciparum (PfTrxR). This suggests that the TP and TAG moieties of AF may be sequentially eliminated during the transfer of Au(I) to catalytic cysteines of the receptor.
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Leitsch D, Williams CF, Hrdý I. Redox Pathways as Drug Targets in Microaerophilic Parasites. Trends Parasitol 2018; 34:576-589. [PMID: 29807758 DOI: 10.1016/j.pt.2018.04.007] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Revised: 04/27/2018] [Accepted: 04/28/2018] [Indexed: 01/06/2023]
Abstract
The microaerophilic parasites Entamoeba histolytica, Trichomonas vaginalis, and Giardia lamblia jointly cause hundreds of millions of infections in humans every year. Other microaerophilic parasites such as Tritrichomonas foetus and Spironucleus spp. pose a relevant health problem in veterinary medicine. Unfortunately, vaccines against these pathogens are unavailable, but their microaerophilic lifestyle opens opportunities for specifically developed chemotherapeutics. In particular, their high sensitivity towards oxygen can be exploited by targeting redox enzymes. This review focusses on the redox pathways of microaerophilic parasites and on drugs, either already in use or currently in the state of development, which target these pathways.
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Affiliation(s)
- David Leitsch
- Institute for Specific Prophylaxis and Tropical Medicine, Center for Pathophysiology, Infectiology, and Immunology, Medical University of Vienna, Austria.
| | - Catrin F Williams
- School of Engineering, Cardiff University, Cardiff, Wales, United Kingdom
| | - Ivan Hrdý
- Department of Parasitology, Charles University, Faculty of Science, Prague, Czech Republic
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May HC, Yu JJ, Guentzel MN, Chambers JP, Cap AP, Arulanandam BP. Repurposing Auranofin, Ebselen, and PX-12 as Antimicrobial Agents Targeting the Thioredoxin System. Front Microbiol 2018; 9:336. [PMID: 29556223 PMCID: PMC5844926 DOI: 10.3389/fmicb.2018.00336] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2017] [Accepted: 02/12/2018] [Indexed: 01/23/2023] Open
Abstract
As microbial resistance to drugs continues to rise at an alarming rate, finding new ways to combat pathogens is an issue of utmost importance. Development of novel and specific antimicrobial drugs is a time-consuming and expensive process. However, the re-purposing of previously tested and/or approved drugs could be a feasible way to circumvent this long and costly process. In this review, we evaluate the U.S. Food and Drug Administration tested drugs auranofin, ebselen, and PX-12 as antimicrobial agents targeting the thioredoxin system. These drugs have been shown to act on bacterial, fungal, protozoan, and helminth pathogens without significant toxicity to the host. We propose that the thioredoxin system could serve as a useful therapeutic target with broad spectrum antimicrobial activity.
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Affiliation(s)
- Holly C. May
- South Texas Center for Emerging Infectious Disease, University of Texas at San Antonio, San Antonio, TX, United States
- Center for Excellence in Infection Genomics, University of Texas at San Antonio, San Antonio, TX, United States
| | - Jieh-Juen Yu
- South Texas Center for Emerging Infectious Disease, University of Texas at San Antonio, San Antonio, TX, United States
- Center for Excellence in Infection Genomics, University of Texas at San Antonio, San Antonio, TX, United States
| | - M. N. Guentzel
- South Texas Center for Emerging Infectious Disease, University of Texas at San Antonio, San Antonio, TX, United States
- Center for Excellence in Infection Genomics, University of Texas at San Antonio, San Antonio, TX, United States
| | - James P. Chambers
- South Texas Center for Emerging Infectious Disease, University of Texas at San Antonio, San Antonio, TX, United States
- Center for Excellence in Infection Genomics, University of Texas at San Antonio, San Antonio, TX, United States
| | - Andrew P. Cap
- United States Army Institute for Surgical Research, San Antonio Military Medical Center, San Antonio, TX, United States
| | - Bernard P. Arulanandam
- South Texas Center for Emerging Infectious Disease, University of Texas at San Antonio, San Antonio, TX, United States
- Center for Excellence in Infection Genomics, University of Texas at San Antonio, San Antonio, TX, United States
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6
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Westrop GD, Wang L, Blackburn GJ, Zhang T, Zheng L, Watson DG, Coombs GH. Metabolomic profiling and stable isotope labelling of Trichomonas vaginalis and Tritrichomonas foetus reveal major differences in amino acid metabolism including the production of 2-hydroxyisocaproic acid, cystathionine and S-methylcysteine. PLoS One 2017; 12:e0189072. [PMID: 29267346 PMCID: PMC5739422 DOI: 10.1371/journal.pone.0189072] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Accepted: 11/17/2017] [Indexed: 11/19/2022] Open
Abstract
Trichomonas vaginalis and Tritrichomonas foetus are pathogens that parasitise, respectively, human and bovine urogenital tracts causing disease. Using LC-MS, reference metabolomic profiles were obtained for both species and stable isotope labelling with D-[U-13C6] glucose was used to analyse central carbon metabolism. This facilitated a comparison of the metabolic pathways of T. vaginalis and T. foetus, extending earlier targeted biochemical studies. 43 metabolites, whose identities were confirmed by comparison of their retention times with authentic standards, occurred at more than 3-fold difference in peak intensity between T. vaginalis and T. foetus. 18 metabolites that were removed from or released into the medium during growth also showed more than 3-fold difference between the species. Major differences were observed in cysteine and methionine metabolism in which homocysteine, produced as a bi-product of trans-methylation, is catabolised by methionine γ-lyase in T. vaginalis but converted to cystathionine in T. foetus. Both species synthesise methylthioadenosine by an unusual mechanism, but it is not used as a substrate for methionine recycling. T. vaginalis also produces and exports high levels of S-methylcysteine, whereas only negligible levels were found in T. foetus which maintains significantly higher intracellular levels of cysteine. 13C-labeling confirmed that both cysteine and S-methylcysteine are synthesised by T. vaginalis; S-methylcysteine can be generated by recombinant T. vaginalis cysteine synthase using phosphoserine and methanethiol. T. foetus contained higher levels of ornithine and citrulline than T. vaginalis and exported increased levels of putrescine, suggesting greater flux through the arginine dihydrolase pathway. T. vaginalis produced and exported hydroxy acid derivatives of certain amino acids, particularly 2-hydroxyisocaproic acid derived from leucine, whereas negligible levels of these metabolites occurred in T. foetus.
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Affiliation(s)
- Gareth D. Westrop
- Strathclyde Institute of Pharmacy and Biomedical Science, Strathclyde University, Glasgow, United Kingdom
- * E-mail:
| | - Lijie Wang
- Strathclyde Institute of Pharmacy and Biomedical Science, Strathclyde University, Glasgow, United Kingdom
| | | | - Tong Zhang
- Institute of Cancer Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Liang Zheng
- Pediatric Translational Medicine Institute, Shanghai Children’s Medical Center, Shanghai, China
| | - David G. Watson
- Strathclyde Institute of Pharmacy and Biomedical Science, Strathclyde University, Glasgow, United Kingdom
| | - Graham H. Coombs
- Strathclyde Institute of Pharmacy and Biomedical Science, Strathclyde University, Glasgow, United Kingdom
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7
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The Architecture of Thiol Antioxidant Systems among Invertebrate Parasites. Molecules 2017; 22:molecules22020259. [PMID: 28208651 PMCID: PMC6155587 DOI: 10.3390/molecules22020259] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Accepted: 02/03/2017] [Indexed: 01/14/2023] Open
Abstract
The use of oxygen as the final electron acceptor in aerobic organisms results in an improvement in the energy metabolism. However, as a byproduct of the aerobic metabolism, reactive oxygen species are produced, leaving to the potential risk of an oxidative stress. To contend with such harmful compounds, living organisms have evolved antioxidant strategies. In this sense, the thiol-dependent antioxidant defense systems play a central role. In all cases, cysteine constitutes the major building block on which such systems are constructed, being present in redox substrates such as glutathione, thioredoxin, and trypanothione, as well as at the catalytic site of a variety of reductases and peroxidases. In some cases, the related selenocysteine was incorporated at selected proteins. In invertebrate parasites, antioxidant systems have evolved in a diversity of both substrates and enzymes, representing a potential area in the design of anti-parasite strategies. The present review focus on the organization of the thiol-based antioxidant systems in invertebrate parasites. Differences between these taxa and its final mammal host is stressed. An understanding of the antioxidant defense mechanisms in this kind of parasites, as well as their interactions with the specific host is crucial in the design of drugs targeting these organisms.
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Andrade RM, Reed SL. New drug target in protozoan parasites: the role of thioredoxin reductase. Front Microbiol 2015; 6:975. [PMID: 26483758 PMCID: PMC4588103 DOI: 10.3389/fmicb.2015.00975] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Accepted: 09/02/2015] [Indexed: 01/04/2023] Open
Abstract
Amebiasis causes approximately 70,000 deaths annually and is the third cause of death due to parasites worldwide. It is treated primarily with metronidazole, which has adverse side effects, is mutagenic and carcinogenic, and emergence of resistance is an increasing concern. Unfortunately, better therapeutic alternatives are lacking. Re-purposing of older FDA approved drugs is advantageous to drug discovery since safety and pharmacokinetic effects in humans are already known. In high throughput screening studies, we recently demonstrated that auranofin, a gold containing compound originally approved to treat rheumatoid arthritis, has activity against trophozoites of E. histolytica, the causative agent of amebiasis. Auranofin's anti-parasitic activity is attributed to its monovalent gold molecule that readily inhibits E. histolytica thioredoxin reductase. This anti-oxidant enzyme is the only thiol-dependent flavo-reductase present in E. histolytica. Auranofin has also shown promising activity against other protozoans of significant public health importance. Altogether, this evidence suggests that auranofin has the potential to become a broad spectrum alternative therapeutic agent for diseases with a large global burden.
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Affiliation(s)
- Rosa M Andrade
- Division of Infectious Diseases, Department of Medicine, University of California San Diego La Jolla, CA, USA
| | - Sharon L Reed
- Division of Infectious Diseases, Department of Pathology, School of Medicine, University of California San Diego La Jolla, CA, USA
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Hypervalent organotellurium compounds as inhibitors of P. falciparum calcium-dependent cysteine proteases. Parasitol Int 2015; 65:20-22. [PMID: 26384965 DOI: 10.1016/j.parint.2015.09.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2015] [Revised: 09/11/2015] [Accepted: 09/14/2015] [Indexed: 11/21/2022]
Abstract
Hypervalent organotellurium compounds (organotelluranes) have shown several promising applications, including their use as potent and selective cysteine protease inhibitors and antiprotozoal agents. Here, we report the antimalarial activities of three organotellurane derivatives (RF05, RF07 and RF19) in two Plasmodium falciparum strains (CQS 3D7 and CQR W2), which demonstrated significant decreases in parasitemia in vitro. The inhibition of intracellular P. falciparum proteases by RF05, RF07 and RF19 was determined and the IC50 values were 3.7±1.0μM, 1.1±0.2μM and 0.2±0.01μM, respectively. Using an assay performed in the presence of the ER Ca(2+)-ATPase inhibitor we showed that the main enzymatic targets were cysteine proteases stimulated by calcium (calpains). None of the compounds tested caused haemolysis or a significant decrease in endothelial cell viability in the concentration range used for the inhibition assay. Taken together, the results suggest promising compounds for the development of antimalarial drugs.
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10
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Comparsi B, Meinerz DF, Dalla Corte CL, Prestes AS, Stefanello ST, Santos DB, Souza DD, Farina M, Dafre AL, Posser T, Franco JL, Rocha JBT. N-acetylcysteine does not protect behavioral and biochemical toxicological effect after acute exposure of diphenyl ditelluride. Toxicol Mech Methods 2014; 24:529-35. [DOI: 10.3109/15376516.2014.920449] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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11
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Halpert G, Sredni B. The effect of the novel tellurium compound AS101 on autoimmune diseases. Autoimmun Rev 2014; 13:1230-5. [PMID: 25153485 DOI: 10.1016/j.autrev.2014.08.003] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2014] [Accepted: 07/30/2014] [Indexed: 02/06/2023]
Abstract
Tellurium is a rare element, which has been regarded as a non-essential trace element despite its relative abundance in the human body. The chemistry of tellurium supports a plethora of activities, but its biochemistry is not clearly established to date. The small tellurium(IV) compound, ammonium trichloro (dioxoethylene-o,o')tellurate (AS101) developed and initially investigated by us, is currently being evaluated in Phase II clinical trials in psoriasis patients. AS101 is the first tellurium compound to be tested for clinical efficacy. This compound is a potent immunomodulator both in vitro and in vivo with a variety of potential therapeutic applications. The present review will focus on the immunomodulatory properties of AS101, and specifically, its effects in mitigating autoimmune diseases. AS101 has several activities that act on the immune system, including: 1) its ability to reduce IL-17 levels and to inhibit the function of Th17 cells; 2) its specific unique redox-modulating activities enabling the inhibition of specific leukocyte integrins such as α4β1 and α4β7, that are pivotal for diapedesis of macrophages and CD4(+) T inflammatory/auto-reactive cells into the autoimmune tissues; and 3) its ability to enhance the activity of regulatory T cells (Treg). These activities coupled with its excellent safety profile suggest that AS101 may be a promising candidate for the management of autoimmune diseases.
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Affiliation(s)
- Gilad Halpert
- C.A.I.R. Institute, The Safdié AIDS and Immunology Research Center, The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 52900, Israel
| | - Benjamin Sredni
- C.A.I.R. Institute, The Safdié AIDS and Immunology Research Center, The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 52900, Israel.
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Amorati R, Valgimigli L, Dinér P, Bakhtiari K, Saeedi M, Engman L. Multi-faceted Reactivity of Alkyltellurophenols Towards Peroxyl Radicals: Catalytic Antioxidant Versus Thiol-Depletion Effect. Chemistry 2013; 19:7510-22. [DOI: 10.1002/chem.201300451] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2013] [Indexed: 11/08/2022]
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Main-Group Medicinal Chemistry Including Li and Bi*. COMPREHENSIVE INORGANIC CHEMISTRY II 2013. [PMCID: PMC7152213 DOI: 10.1016/b978-0-08-097774-4.00338-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Main-group element compounds were among the first developed in the modern era as pharmaceutical preparations for the treatment of a wide variety of human ailments; it is now recognized that many of these elements exist in traditional medicine of many societies, for example, arsenic. The use of main-group element compounds in contemporary medicine continues for the treatment of, for example, depression (Li), stomach ulcers (Bi), cancer (As and Ga), and leishmaniasis (Sb). Not surprisingly, new compounds of these elements, and other main-group elements, continue to be investigated for their potential use in new therapies. In this chapter, the use of main-group elements as therapeutic agents is outlined and also, where understood, comments on biological targets and mechanisms of action. Further, key advances in new potential applications of main-group element compounds in medicine are evaluated.
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Caracelli I, Vega-Teijido M, Zukerman-Schpector J, Cezari MH, Lopes JG, Juliano L, Santos PS, Comasseto JV, Cunha RL, Tiekink ER. A tellurium-based cathepsin B inhibitor: Molecular structure, modelling, molecular docking and biological evaluation. J Mol Struct 2012. [DOI: 10.1016/j.molstruc.2012.01.008] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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Tiekink ERT. Therapeutic potential of selenium and tellurium compounds: opportunities yet unrealised. Dalton Trans 2012; 41:6390-5. [PMID: 22252404 DOI: 10.1039/c2dt12225a] [Citation(s) in RCA: 129] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Despite being disparaged for their malodorous and toxic demeanour, compounds of selenium, a bio-essential element, and tellurium, offer possibilities as therapeutic agents. Herein, their potential use as drugs, for example, as anti-viral, anti-microbial, anti-inflammatory agents, etc., will be surveyed along with a summary of the established biological functions of selenium. The natural biological functions of tellurium remain to be discovered.
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Affiliation(s)
- Edward R T Tiekink
- Department of Chemistry, University of Malaya, 50603, Kuala, Lumpur, Malaysia.
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Mechanistic studies on the enzymatic processing of fluorinated methionine analogues by Trichomonas vaginalis methionine γ-lyase. Biochem J 2011; 438:513-21. [DOI: 10.1042/bj20101986] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
TFM (L-trifluoromethionine), a potential prodrug, was reported to be toxic towards human pathogens that express MGL (L-methionine γ-lyase; EC 4.4.1.11), a pyridoxal phosphate-containing enzyme that converts L-methionine into α-oxobutyrate, ammonia and methyl mercaptan. It has been hypothesized that the extremely reactive thiocarbonyl difluoride is produced when the enzyme acts upon TFM, resulting in cellular toxicity. The potential application of the fluorinated thiomethyl group in other areas of biochemistry and medicinal chemistry requires additional studies. Therefore a detailed investigation of the theoretical and experimental chemistry and biochemistry of these fluorinated groups (CF3S− and CF2HS−) has been undertaken to trap and identify chemical intermediates produced by enzyme processing of molecules containing these fluorinated moieties. TvMGL (MGL from Trichomonas vaginalis) and a chemical model system of the reaction were utilized in order to investigate the cofactor-dependent activation of TFM and previously uninvestigated DFM (L-difluoromethionine). The differences in toxicity between TFM and DFM were evaluated against Escherichia coli expressing TvMGL1, as well as the intact human pathogen T. vaginalis. The relationship between the chemical structure of the reactive intermediates produced from the enzymatic processing of these analogues and their cellular toxicity are discussed.
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González-Siso MI, García-Leiro A, Tarrío N, Cerdán ME. Sugar metabolism, redox balance and oxidative stress response in the respiratory yeast Kluyveromyces lactis. Microb Cell Fact 2009; 8:46. [PMID: 19715615 PMCID: PMC2754438 DOI: 10.1186/1475-2859-8-46] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2009] [Accepted: 08/30/2009] [Indexed: 12/04/2022] Open
Abstract
A lot of studies have been carried out on Saccharomyces cerevisiae, an yeast with a predominant fermentative metabolism under aerobic conditions, which allows exploring the complex response induced by oxidative stress. S. cerevisiae is considered a eukaryote model for these studies. We propose Kluyveromyces lactis as a good alternative model to analyse variants in the oxidative stress response, since the respiratory metabolism in this yeast is predominant under aerobic conditions and it shows other important differences with S. cerevisiae in catabolic repression and carbohydrate utilization. The knowledge of oxidative stress response in K. lactis is still a developing field. In this article, we summarize the state of the art derived from experimental approaches and we provide a global vision on the characteristics of the putative K. lactis components of the oxidative stress response pathway, inferred from their sequence homology with the S. cerevisiae counterparts. Since K. lactis is also a well-established alternative host for industrial production of native enzymes and heterologous proteins, relevant differences in the oxidative stress response pathway and their potential in biotechnological uses of this yeast are also reviewed.
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Affiliation(s)
- M Isabel González-Siso
- Department of Molecular and Cell Biology, University of A Coruña, Campus da Zapateira s/n, 15071- A Coruña, Spain.
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