1
|
Grzechowiak M, Sliwiak J, Link A, Ruszkowski M. Legume-type glutamate dehydrogenase: Structure, activity, and inhibition studies. Int J Biol Macromol 2024; 278:134648. [PMID: 39142482 DOI: 10.1016/j.ijbiomac.2024.134648] [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: 02/28/2024] [Revised: 06/28/2024] [Accepted: 08/08/2024] [Indexed: 08/16/2024]
Abstract
Glutamate dehydrogenases (GDHs) are key enzymes at the crossroads of N and C metabolism in plants. Legumes, whose N metabolism is particularly intricate, possess a unique type of GDH. This study presents an analysis of a legume-type GDH (isoform 2) from Medicago truncatula (MtGDH2). We measured MtGDH2 activity in both the Glu → 2-oxoglutarate (2OG) and 2OG → Glu reaction directions and obtained kinetic parameters for Glu, 2OG, NAD+, and NADH. Inhibition assays revealed that compounds possessing di- or tricarboxylates act as inhibitors of plant GDHs. Interestingly, 2,6-pyridinedicarboxylate (PYR) weakly inhibits MtGDH2 compared to Arabidopsis thaliana homologs. Furthermore, we explored tetrazole derivatives to discover 3-(1H-tetrazol-5-yl)benzoic acid (TBA) as an MtGDH2 inhibitor. The kinetic experiments are supported by six crystal structures, solved as: (i) unliganded enzyme, (ii) trapping the reaction intermediate 2-amino-2-hydroxyglutarate and NAD+, and also complexed with NAD+ and inhibitors such as (iii) citrate, (iv) PYR, (v) isophthalate, and (vi) TBA. The complex with TBA revealed a new mode of action that, in contrast to other inhibitors, prevents domain closure. This discovery points to TBA as a starting point for the development of novel GDH inhibitors to study the functions of GDH in plants and potentially boost biomass production.
Collapse
Affiliation(s)
- Marta Grzechowiak
- Department of Structural Biology of Eukaryotes, Institute of Bioorganic Chemistry, Polish Academy of Sciences, Poznan 61-704, Poland
| | - Joanna Sliwiak
- Laboratory of Protein Engineering, Institute of Bioorganic Chemistry, Polish Academy of Sciences, Poznan 61-704, Poland
| | - Andreas Link
- Department of Pharmaceutical and Medicinal Chemistry, Institute of Pharmacy, University of Greifswald, 17489 Greifswald, Germany
| | - Milosz Ruszkowski
- Department of Structural Biology of Eukaryotes, Institute of Bioorganic Chemistry, Polish Academy of Sciences, Poznan 61-704, Poland.
| |
Collapse
|
2
|
Naik B, Gupta N, Godara P, Srivastava V, Kumar P, Giri R, Prajapati VK, Pandey KC, Prusty D. Structure-based virtual screening approach reveals natural multi-target compounds for the development of antimalarial drugs to combat drug resistance. J Biomol Struct Dyn 2024; 42:7384-7408. [PMID: 37528665 DOI: 10.1080/07391102.2023.2240415] [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: 01/19/2023] [Accepted: 07/17/2023] [Indexed: 08/03/2023]
Abstract
Compared to the previous year, there has been an increase of nearly 2 million malaria cases in 2021. The emergence of drug-resistant strains of Plasmodium falciparum, the most deadly malaria parasite, has led to a decline in the effectiveness of existing antimalarial drugs. To address this problem, the present study aimed to identify natural compounds with the potential to inhibit multiple validated antimalarial drug targets. The natural compounds from the Natural Product Activity and Species Source (NPASS) database were screened against ten validated drug targets of Plasmodium falciparum using a structure-based molecular docking method. Twenty compounds, with targets ranging from three to five, were determined as the top hits. The molecular dynamics simulations of the top six complexes (NPC246162 in complex with PfAdSS, PfGDH, and PfNMT; NPC271270 in complex with PfCK, PfGDH, and PfdUTPase) confirmed their stable binding affinity in the dynamic environment. The Tanimoto coefficient and distance matrix score analysis show the structural divergence of all the hit compounds from known antimalarials, indicating minimum chances of cross-resistance. Thus, we propose further investigating these compounds in biochemical and parasite inhibition studies to reveal the real therapeutic potential. If found successful, these compounds may be a new avenue for future drug discovery efforts to combat existing antimalarial drug resistance.Communicated by Ramaswamy H. Sarma.
Collapse
Affiliation(s)
- Biswajit Naik
- Department of Biochemistry, School of Life Sciences, Central University of Rajasthan, Ajmer, India
| | - Nidhi Gupta
- Department of Biochemistry, School of Life Sciences, Central University of Rajasthan, Ajmer, India
| | - Priya Godara
- Department of Biochemistry, School of Life Sciences, Central University of Rajasthan, Ajmer, India
| | - Varshita Srivastava
- Department of Biochemistry, School of Life Sciences, Central University of Rajasthan, Ajmer, India
| | - Prateek Kumar
- School of Basic Sciences, Indian Institute of Technology Mandi, Kamand, India
| | - Rajanish Giri
- School of Basic Sciences, Indian Institute of Technology Mandi, Kamand, India
| | - Vijay Kumar Prajapati
- Department of Biochemistry, School of Life Sciences, Central University of Rajasthan, Ajmer, India
| | - Kailash C Pandey
- Icmr-National Institute of Malaria Research, And Academy of Scientific and Innovative Research (AcSIR-ICMR), India
| | - Dhaneswar Prusty
- Department of Biochemistry, School of Life Sciences, Central University of Rajasthan, Ajmer, India
| |
Collapse
|
3
|
Godsora BKJ, Prakash P, Punekar NS, Bhaumik P. Molecular insights into the inhibition of glutamate dehydrogenase by the dicarboxylic acid metabolites. Proteins 2021; 90:810-823. [PMID: 34748226 DOI: 10.1002/prot.26276] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 11/02/2021] [Accepted: 11/03/2021] [Indexed: 12/20/2022]
Abstract
Glutamate dehydrogenase (GDH) is a salient metabolic enzyme which catalyzes the NAD+ - or NADP+ -dependent reversible conversion of α-ketoglutarate (AKG) to l-glutamate; and thereby connects the carbon and nitrogen metabolism cycles in all living organisms. The function of GDH is extensively regulated by both metabolites (citrate, succinate, etc.) and non-metabolites (ATP, NADH, etc.) but sufficient molecular evidences are lacking to rationalize the inhibitory effects by the metabolites. We have expressed and purified NADP+ -dependent Aspergillus terreus GDH (AtGDH) in recombinant form. Succinate, malonate, maleate, fumarate, and tartrate independently inhibit the activity of AtGDH to different extents. The crystal structures of AtGDH complexed with the dicarboxylic acid metabolites and the coenzyme NADPH have been determined. Although AtGDH structures are not complexed with substrate; surprisingly, they acquire super closed conformation like previously reported for substrate and coenzyme bound catalytically competent Aspergillus niger GDH (AnGDH). These dicarboxylic acid metabolites partially occupy the same binding pocket as substrate; but interact with varying polar interactions and the coenzyme NADPH binds to the Domain-II of AtGDH. The low inhibition potential of tartrate as compared to other dicarboxylic acid metabolites is due to its weaker interactions of carboxylate groups with AtGDH. Our results suggest that the length of carbon skeleton and positioning of the carboxylate groups of inhibitors between two conserved lysine residues at the GDH active site might be the determinants of their inhibitory potency. Molecular details on the dicarboxylic acid metabolites bound AtGDH active site architecture presented here would be applicable to GDHs in general.
Collapse
Affiliation(s)
| | - Prem Prakash
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai, Maharashtra, India
| | - Narayan S Punekar
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai, Maharashtra, India
| | - Prasenjit Bhaumik
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai, Maharashtra, India
| |
Collapse
|
4
|
Mapping the Intramolecular Communications among Different Glutamate Dehydrogenase States Using Molecular Dynamics. Biomolecules 2021; 11:biom11060798. [PMID: 34072154 PMCID: PMC8228935 DOI: 10.3390/biom11060798] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Revised: 05/18/2021] [Accepted: 05/25/2021] [Indexed: 12/23/2022] Open
Abstract
Glutamate dehydrogenase (GDH) is a ubiquitous enzyme that catalyzes the reversible oxidative deamination of glutamate to α-ketoglutarate. It acts as an important branch-point enzyme between carbon and nitrogen metabolisms. Due to the multifaceted roles of GDH in cancer, hyperinsulinism/hyperammonemia, and central nervous system development and pathologies, tight control of its activity is necessitated. To date, several GDH structures have been solved in its closed form; however, intrinsic structural information in its open and apo forms are still deficient. Moreover, the allosteric communications and conformational changes taking place in the three different GDH states are not well studied. To mitigate these drawbacks, we applied unbiased molecular dynamic simulations (MD) and network analysis to three different GDH states i.e., apo, active, and inactive forms, for investigating their modulatory mechanisms. In this paper, based on MD and network analysis, crucial residues important for signal transduction, conformational changes, and maps of information flow among the different GDH states were elucidated. Moreover, with the recent findings of allosteric modulators, an allosteric wiring illustration of GDH intramolecular signal transductions would be of paramount importance to obtain the process of this enzyme regulation. The structural insights gained from this study will pave way for large-scale screening of GDH regulators and could support researchers in the design and development of new and potent GDH ligands.
Collapse
|
5
|
Tiwari S, Sharma N, Sharma GP, Mishra N. Redox interactome in malaria parasite Plasmodium falciparum. Parasitol Res 2021; 120:423-434. [PMID: 33459846 DOI: 10.1007/s00436-021-07051-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Accepted: 01/08/2021] [Indexed: 11/26/2022]
Abstract
The malaria-causing parasite Plasmodium falciparum is a severe threat to human health across the globe. This parasite alone causes the highest morbidity and mortality than any other species of Plasmodium. The parasites dynamically multiply in the erythrocytes of the vertebrate hosts, a large number of reactive oxygen species that damage biological macromolecules are produced in the cell during parasite growth. To relieve this intense oxidative stress, the parasite employs an NADPH-dependent thioredoxin and glutathione system that acts as an antioxidant and maintains redox status in the parasite. The mutual interaction of both redox proteins is involved in various biological functions and the survival of the erythrocytic stage of the parasite. Since the Plasmodium species is deficient in catalase and classical glutathione peroxidase, so their redox balance relies on a complex set of five peroxiredoxins, differentially positioned in the cytosol, mitochondria, apicoplast, and nucleus with partly overlapping substrate preferences. Moreover, Plasmodium falciparum possesses a set of members belonging to the thioredoxin superfamily, such as three thioredoxins, two thioredoxin-like proteins, one dithiol, three monocysteine glutaredoxins, and one redox-active plasmoredoxin with largely redundant functions. This review paper aims to discuss and encapsulate the biological function and current knowledge of the functional redox network of Plasmodium falciparum.
Collapse
Affiliation(s)
- Savitri Tiwari
- Parasite-Host Biology Group, National Institute of Malaria Research, Indian Council of Medical Research, Sector-8, Dwarka, New Delhi, 110077, India
| | - Nivedita Sharma
- Parasite-Host Biology Group, National Institute of Malaria Research, Indian Council of Medical Research, Sector-8, Dwarka, New Delhi, 110077, India
| | | | - Neelima Mishra
- Parasite-Host Biology Group, National Institute of Malaria Research, Indian Council of Medical Research, Sector-8, Dwarka, New Delhi, 110077, India.
| |
Collapse
|
6
|
Dousti M, Manzano-Román R, Rashidi S, Barzegar G, Ahmadpour NB, Mohammadi A, Hatam G. A proteomic glimpse into the effect of antimalarial drugs on Plasmodium falciparum proteome towards highlighting possible therapeutic targets. Pathog Dis 2021; 79:ftaa071. [PMID: 33202000 DOI: 10.1093/femspd/ftaa071] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Accepted: 11/13/2020] [Indexed: 02/07/2023] Open
Abstract
There is no effective vaccine against malaria; therefore, chemotherapy is to date the only choice to fight against this infectious disease. However, there is growing evidences of drug-resistance mechanisms in malaria treatments. Therefore, the identification of new drug targets is an urgent need for the clinical management of the disease. Proteomic approaches offer the chance of determining the effects of antimalarial drugs on the proteome of Plasmodium parasites. Accordingly, we reviewed the effects of antimalarial drugs on the Plasmodium falciparum proteome pointing out the relevance of several proteins as possible drug targets in malaria treatment. In addition, some of the P. falciparum stage-specific altered proteins and parasite-host interactions might play important roles in pathogenicity, survival, invasion and metabolic pathways and thus serve as potential sources of drug targets. In this review, we have identified several proteins, including thioredoxin reductase, helicases, peptidyl-prolyl cis-trans isomerase, endoplasmic reticulum-resident calcium-binding protein, choline/ethanolamine phosphotransferase, purine nucleoside phosphorylase, apical membrane antigen 1, glutamate dehydrogenase, hypoxanthine guanine phosphoribosyl transferase, heat shock protein 70x, knob-associated histidine-rich protein and erythrocyte membrane protein 1, as promising antimalarial drugs targets. Overall, proteomic approaches are able to partially facilitate finding possible drug targets. However, the integration of other 'omics' and specific pharmaceutical techniques with proteomics may increase the therapeutic properties of the critical proteins identified in the P. falciparum proteome.
Collapse
Affiliation(s)
- Majid Dousti
- Department of Parasitology and Mycology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Raúl Manzano-Román
- Proteomics Unit, Cancer Research Centre (IBMCC/CSIC/USAL/IBSAL), 37007, Salamanca, Spain
| | - Sajad Rashidi
- Department of Parasitology and Mycology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Gholamreza Barzegar
- Department of Parasitology and Mycology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
| | | | - Alireza Mohammadi
- Department of Disease Control, Komijan Treatment and Health Network, Arak University of Medical Science, Iran
| | - Gholamreza Hatam
- Basic Sciences in Infectious Diseases Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| |
Collapse
|
7
|
Grzechowiak M, Sliwiak J, Jaskolski M, Ruszkowski M. Structural Studies of Glutamate Dehydrogenase (Isoform 1) From Arabidopsis thaliana, an Important Enzyme at the Branch-Point Between Carbon and Nitrogen Metabolism. FRONTIERS IN PLANT SCIENCE 2020; 11:754. [PMID: 32655590 PMCID: PMC7326016 DOI: 10.3389/fpls.2020.00754] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Accepted: 05/12/2020] [Indexed: 05/24/2023]
Abstract
Glutamate dehydrogenase (GDH) releases ammonia in a reversible NAD(P)+-dependent oxidative deamination of glutamate that yields 2-oxoglutarate (2OG). In current perception, GDH contributes to Glu homeostasis and plays a significant role at the junction of carbon and nitrogen assimilation pathways. GDHs are members of a superfamily of ELFV (Glu/Leu/Phe/Val) amino acid dehydrogenases and are subdivided into three subclasses, based on coenzyme specificity: NAD+-specific, NAD+/NADP+ dual-specific, and NADP+-specific. We determined in this work that the mitochondrial AtGDH1 isozyme from A. thaliana is NAD+-specific. Altogether, A. thaliana expresses three GDH isozymes (AtGDH1-3) targeted to mitochondria, of which AtGDH2 has an extra EF-hand motif and is stimulated by calcium. Our enzymatic assays of AtGDH1 established that its sensitivity to calcium is negligible. In vivo the AtGDH1-3 enzymes form homo- and heterohexamers of varied composition. We solved the crystal structure of recombinant AtGDH1 in the apo-form and in complex with NAD+ at 2.59 and 2.03 Å resolution, respectively. We demonstrate also that both in the apo form and in 1:1 complex with NAD+, it forms D 3-symmetric homohexamers. A subunit of AtGDH1 consists of domain I, which is involved in hexamer formation and substrate binding, and of domain II which binds coenzyme. Most of the subunits in our crystal structures, including those in NAD+ complex, are in open conformation, with domain II forming a large (albeit variable) angle with domain I. One of the subunits of the AtGDH1-NAD+ hexamer contains a serendipitous 2OG molecule in the active site, causing a dramatic (∼25°) closure of the domains. We provide convincing evidence that the N-terminal peptide preceding domain I is a mitochondrial targeting signal, with a predicted cleavage site for mitochondrial processing peptidase (MPP) at Leu17-Leu18 that is followed by an unexpected potassium coordination site (Ser27, Ile30). We also identified several MPD [(+/-)-2-methyl-2,4-pentanediol] binding sites with conserved sequence. Although AtGDH1 is insensitive to MPD in our assays, the observation of druggable sites opens a potential for non-competitive herbicide design.
Collapse
Affiliation(s)
- Marta Grzechowiak
- Center for Biocrystallographic Research Institute of Bioorganic Chemistry, Polish Academy of Sciences, Poznań, Poland
| | - Joanna Sliwiak
- Center for Biocrystallographic Research Institute of Bioorganic Chemistry, Polish Academy of Sciences, Poznań, Poland
| | - Mariusz Jaskolski
- Center for Biocrystallographic Research Institute of Bioorganic Chemistry, Polish Academy of Sciences, Poznań, Poland
- Department of Crystallography, Faculty of Chemistry, Adam Mickiewicz University, Poznań, Poland
| | - Milosz Ruszkowski
- Center for Biocrystallographic Research Institute of Bioorganic Chemistry, Polish Academy of Sciences, Poznań, Poland
| |
Collapse
|
8
|
Yadav DK, Kumar S, Teli MK, Yadav R, Chaudhary S. Molecular Targets for Malarial Chemotherapy: A Review. Curr Top Med Chem 2019; 19:861-873. [DOI: 10.2174/1568026619666190603080000] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2019] [Revised: 02/08/2019] [Accepted: 02/08/2019] [Indexed: 11/22/2022]
Abstract
The malaria parasite resistance to the existing drugs is a serious problem to the currently used
antimalarials and, thus, highlights the urgent need to develop new and effective anti-malarial molecules.
This could be achieved either by the identification of the new drugs for the validated targets or by further
refining/improving the existing antimalarials; or by combining previously effective agents with
new/existing drugs to have a synergistic effect that counters parasite resistance; or by identifying novel
targets for the malarial chemotherapy. In this review article, a comprehensive collection of some of the
novel molecular targets has been enlisted for the antimalarial drugs. The targets which could be deliberated
for developing new anti-malarial drugs could be: membrane biosynthesis, mitochondrial system,
apicoplasts, parasite transporters, shikimate pathway, hematin crystals, parasite proteases, glycolysis,
isoprenoid synthesis, cell cycle control/cycline dependent kinase, redox system, nucleic acid metabolism,
methionine cycle and the polyamines, folate metabolism, the helicases, erythrocyte G-protein, and
farnesyl transferases. Modern genomic tools approaches such as structural biology and combinatorial
chemistry, novel targets could be identified followed by drug development for drug resistant strains providing
wide ranges of novel targets in the development of new therapy. The new approaches and targets
mentioned in the manuscript provide a basis for the development of new unique strategies for antimalarial
therapy with limited off-target effects in the near future.
Collapse
Affiliation(s)
- Dharmendra K. Yadav
- College of Pharmacy, Gachon University of Medicine and Science, Hambakmoeiro, 191, Yeonsu-gu, Incheon 406-799, South Korea
| | - Surendra Kumar
- College of Pharmacy, Gachon University of Medicine and Science, Hambakmoeiro, 191, Yeonsu-gu, Incheon 406-799, South Korea
| | - Mahesh K. Teli
- College of Pharmacy, Gachon University of Medicine and Science, Hambakmoeiro, 191, Yeonsu-gu, Incheon 406-799, South Korea
| | - Ravikant Yadav
- Laboratory of Organic and Medicinal Chemistry, Department of Chemistry, Malaviya National Institute of Technology, Jawaharlal Nehru Marg, Jaipur-302017, India
| | - Sandeep Chaudhary
- Laboratory of Organic and Medicinal Chemistry, Department of Chemistry, Malaviya National Institute of Technology, Jawaharlal Nehru Marg, Jaipur-302017, India
| |
Collapse
|
9
|
Haeussler K, Fritz-Wolf K, Reichmann M, Rahlfs S, Becker K. Characterization of Plasmodium falciparum 6-Phosphogluconate Dehydrogenase as an Antimalarial Drug Target. J Mol Biol 2018; 430:4049-4067. [DOI: 10.1016/j.jmb.2018.07.030] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Revised: 07/27/2018] [Accepted: 07/27/2018] [Indexed: 12/14/2022]
|
10
|
Development of an aptamer-based field effect transistor biosensor for quantitative detection of Plasmodium falciparum glutamate dehydrogenase in serum samples. Biosens Bioelectron 2018; 123:30-35. [PMID: 30308419 DOI: 10.1016/j.bios.2018.09.085] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Revised: 09/13/2018] [Accepted: 09/25/2018] [Indexed: 02/07/2023]
Abstract
There has been a continuous strive to develop portable, stable, sensitive and low cost detection system for malaria to meet the demand of effective screening actions in developing countries where the disease is most endemic. Herein, we report an aptamer-based field effect transistor (aptaFET) biosensor, developed by using an extended gate field effect transistor with inter-digitated gold microelectrodes (IDµE) for the detection of the malaria biomarker Plasmodium falciparum glutamate dehydrogenase (PfGDH) in serum samples. A 90 mer long ssDNA aptamer (NG3) selective to PfGDH was used in the aptaFET to capture the target protein. The intrinsic surface net charge of the captured protein led to change in gate potential of the aptaFET device, which could be correlated to the concentration of the protein. This biosensor exhibited a sensitive response in broad dynamic range of 100 fM -10 nM with limits of detection of 16.7 pM and 48.6 pM in spiked buffer and serum samples, respectively. The high selectivity of the biosensor for PfGDH was verified by testing relevant analogous human and parasitic proteins on the device. Overall, the results validated the application potential of the developed aptaFET for diagnosis of both symptomatic and asymptomatic malaria.
Collapse
|
11
|
Singh NK, Chakma B, Jain P, Goswami P. Protein-Induced Fluorescence Enhancement Based Detection of Plasmodium falciparum Glutamate Dehydrogenase Using Carbon Dot Coupled Specific Aptamer. ACS COMBINATORIAL SCIENCE 2018; 20:350-357. [PMID: 29722521 DOI: 10.1021/acscombsci.8b00021] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
A novel 90-mer long ssDNA aptamer (NG3) covering a 40-mer random region targeting Plasmodium falciparum glutamate dehydrogenase ( PfGDH) developed through systematic evolution of ligands by exponential enrichment (SELEX) technique. The binding affinity of the aptamer to PfGDH discerned by circular dichroism (CD) was 0.5 ± 0.04 μM. The specificity of the aptamer toward the target was confirmed by gel electrophoresis and CD studies. The presence of two quadruplex forming regions, two big and four small stem loop structures with a δG of -7.99 kcal mol-1 for NG3 were deduced by computational studies. The spherical carbon dots (Cdots) of size 2-4 nm, synthesized by pyrolysis method using l-glutamate as a substrate were covalently linked to the amine modified aptamer. The Cdot with a band gap of 2.8 eV and a quantum yield of 34% produced fluorescence at ∼ λ410 nm when excited at λ320nm. The quantum yield of Cdot-aptamer assembly was increased up to 40% in the presence of the PfGDH in solution. A linear relationship with a dynamic range of 0.5 nM to 25 nM (R2 = 0.98) and a limit of detection (LOD) of 0.48 nM was observed between the fluorescence intensity of the Cdots-aptamer conjugate and the concentration of PfGDH. The method could detect PfGDH with an LOD of 2.85 nM in diluted serum sample. This novel simple, sensitive and specific protein induced fluorescence enhancement based detection of PfGDH has a great potential to develop as a method for malaria detection.
Collapse
Affiliation(s)
- Naveen Kumar Singh
- Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati, Assam 781039, India
| | - Babina Chakma
- Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati, Assam 781039, India
| | - Priyamvada Jain
- Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati, Assam 781039, India
| | - Pranab Goswami
- Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati, Assam 781039, India
| |
Collapse
|
12
|
Prakash P, Punekar NS, Bhaumik P. Structural basis for the catalytic mechanism and α-ketoglutarate cooperativity of glutamate dehydrogenase. J Biol Chem 2018. [PMID: 29540480 DOI: 10.1074/jbc.ra117.000149] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Glutamate dehydrogenase (GDH) is a key enzyme connecting carbon and nitrogen metabolism in all living organisms. Despite extensive studies on GDHs from both prokaryotic and eukaryotic organisms in the last 40 years, the structural basis of the catalytic features of this enzyme remains incomplete. This study reports the structural basis of the GDH catalytic mechanism and allosteric behavior. We determined the first high-resolution crystal structures of glutamate dehydrogenase from the fungus Aspergillus niger (AnGDH), a unique NADP+-dependent allosteric enzyme that is forward-inhibited by the formation of mixed disulfide. We determined the structures of the active enzyme in its apo form and in binary/ternary complexes with bound substrate (α-ketoglutarate), inhibitor (isophthalate), coenzyme (NADPH), or two reaction intermediates (α-iminoglutarate and 2-amino-2-hydroxyglutarate). The structure of the forward-inhibited enzyme (fiAnGDH) was also determined. The hexameric AnGDH had three open subunits at one side and three partially closed protomers at the other, a configuration not previously reported. The AnGDH hexamers having subunits with different conformations indicated that its α-ketoglutarate-dependent homotropic cooperativity follows the Monod-Wyman-Changeux (MWC) model. Moreover, the position of the water attached to Asp-154 and Gly-153 defined the previously unresolved ammonium ion-binding pocket, and the binding site for the 2'-phosphate group of the coenzyme was also better defined by our structural data. Additional structural and mutagenesis experiments identified the residues essential for coenzyme recognition. This study reveals the structural features responsible for positioning α-ketoglutarate, NADPH, ammonium ion, and the reaction intermediates in the GDH active site.
Collapse
Affiliation(s)
- Prem Prakash
- From the Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai-400076, India
| | - Narayan S Punekar
- From the Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai-400076, India
| | - Prasenjit Bhaumik
- From the Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai-400076, India
| |
Collapse
|
13
|
Tomita T, Yin L, Nakamura S, Kosono S, Kuzuyama T, Nishiyama M. Crystal structure of the 2-iminoglutarate-bound complex of glutamate dehydrogenase from Corynebacterium glutamicum. FEBS Lett 2017; 591:1611-1622. [PMID: 28486765 DOI: 10.1002/1873-3468.12667] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Revised: 05/02/2017] [Accepted: 05/02/2017] [Indexed: 11/06/2022]
Abstract
The NADP+ -dependent glutamate dehydrogenase from Corynebacterium glutamicum (CgGDH) is considered to be one of the key enzymes in the industrial fermentation of glutamate due to its high glutamate-producing activity. We determined the crystal structure of CgGDH complexed with NADP+ and 2-iminoglutarate. Among six subunits of hexameric CgGDH-binding NADP+ , only four subunits bind 2-iminoglutarate in a closed form, while the other two are in an open form. In the closed form, 2-iminoglutarate is bound to the substrate-binding site with the 2-imino group stacked by the nicotinamide ring of the coenzyme, suggesting a prehydride transfer state in a hypothesized reaction scheme with the imino intermediate. We also conducted MD simulations and provide insights into the extreme preference for the glutamate-producing reaction of CgGDH. DATABASE The atomic coordinate and structure factors have been deposited in the RCSB PDB database under the accession number 5GUD.
Collapse
Affiliation(s)
- Takeo Tomita
- Biotechnology Research Center, The University of Tokyo, Japan
| | - Lulu Yin
- Biotechnology Research Center, The University of Tokyo, Japan
| | - Shugo Nakamura
- Faculty of Information Networking for Innovation and Design, Toyo University, Tokyo, Japan
| | - Saori Kosono
- Biotechnology Research Center, The University of Tokyo, Japan
| | | | | |
Collapse
|
14
|
Seol B, Shin HI, Kim JY, Jeon BY, Kang YJ, Pak JH, Kim TS, Lee HW. Sequence conservation of Plasmodium vivax glutamate dehydrogenase among Korean isolates and its application in seroepidemiology. Malar J 2017; 16:3. [PMID: 28049479 PMCID: PMC5209832 DOI: 10.1186/s12936-016-1653-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Accepted: 12/15/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Glutamate dehydrogenase of malaria parasites (pGDH) is widely used in rapid diagnostic tests for malaria. Variation in the pGDH gene among Korean isolates of Plasmodium vivax was analysed, and a recombinant pGDH protein was evaluated for use as antigens for the serodiagnosis of vivax malaria. METHODS Genomic DNA was purified from blood samples of 20 patients and the pGDH gene of P. vivax was sequenced. Recombinant protein was prepared to determine the antigenicity of pGDH by enzyme-linked immunosorbent assay (ELISA). RESULTS Partial sequence analysis of the P. vivax pGDH gene from the 20 Korean isolates showed that an open reading frame (ORF) of 1410 nucleotides encoded a deduced protein of 470 amino acids. The amino acid and nucleotide sequences were conserved among all the Korean isolates. This ORF showed 100% homology with P. vivax strain Sal-I (GenBank accession No. XP_001616617.1). The full ORF (amino acids 39-503), excluding the region before the intron, was cloned from isolate P. vivax Bucheon 3 (KJ726751) and subcloned into the expression vector pET28b for transformation into Escherichia coli BL21(DE3)pLysS. The expressed recombinant protein had a molecular mass of approximately 55 kDa and showed 84.8% sensitivity (39/46 cases) and 97.2% specificity (35/36 cases) in an ELISA. The efficacy of recombinant pGDH protein in seroepidemiological studies was also evaluated by ELISA using serum samples collected from 876 inhabitants of Gyodong-myeon, Ganghwa County, Incheon Metropolitan City. Of these samples, 91 (10.39%) showed a positive reaction with recombinant pGDH protein. Among the antibody-positive individuals, 13 (14.29%) had experienced malaria infection during the last 10 years. CONCLUSION The pGDH genes of P. vivax isolates from representative epidemic-prone areas of South Korea are highly conserved. Therefore, pGDH is expected to be a useful antigen in seroepidemiological studies. It was difficult to identify the foci of malaria transmission in Gyodong-myeon based on the patient distribution because of the very low parasitaemia of Korean vivax malaria. However, seroepidemiology with recombinant pGDH protein easily identified regions with the highest incidence of malaria within the study area. Therefore, recombinant pGDH protein may have a useful role in serodiagnosis.
Collapse
Affiliation(s)
- Bomin Seol
- Department of Tropical Medicine and Parasitology, Inha University School of Medicine, Incheon, 22212, South Korea
| | - Hyun-Il Shin
- Division of Malaria and Parasitic Diseases, National Institute of Health, Korea Centers for Disease Control and Prevention, Osong, 363-951, South Korea
| | - Jung-Yeon Kim
- Division of Malaria and Parasitic Diseases, National Institute of Health, Korea Centers for Disease Control and Prevention, Osong, 363-951, South Korea
| | - Bo-Young Jeon
- Department of Biomedical Laboratory Science, School of Public Health, College of Health Sciences, Yonsei University, Wonju, 26493, South Korea
| | - Yoon-Joong Kang
- Department of Biomedical Science, Jungwon University, Goesan, Chungbuk, 367-805, South Korea
| | - Jhang-Ho Pak
- Department of Convergence Medicine, Asan Medical Center, University of Ulsan College of Medicine and Asan Institute for Life Sciences, Seoul, 05505, South Korea
| | - Tong-Soo Kim
- Department of Tropical Medicine and Parasitology, Inha University School of Medicine, Incheon, 22212, South Korea.
| | - Hyeong-Woo Lee
- Department of Biomedical Laboratory Science, School of Public Health, College of Health Sciences, Yonsei University, Wonju, 26493, South Korea.
| |
Collapse
|
15
|
Kimoloi S, Rashid K. Potential role of Plasmodium falciparum-derived ammonia in the pathogenesis of cerebral malaria. Front Neurosci 2015; 9:234. [PMID: 26190968 PMCID: PMC4490226 DOI: 10.3389/fnins.2015.00234] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Accepted: 06/18/2015] [Indexed: 12/19/2022] Open
Abstract
Cerebral malaria (CM) is the most severe complication associated with Plasmodium falciparum infection. The exact pathogenic mechanisms leading to the development of CM remains poorly understood while the mortality rates remain high. Several potential mechanisms including mechanical obstruction of brain microvasculature, inflammation, oxidative stress, cerebral energy defects, and hemostatic dysfunction have been suggested to play a role in CM pathogenesis. However, these proposed mechanisms, even when considered together, do not fully explain the pathogenesis and clinicopathological features of human CM. This necessitates consideration of alternative pathogenic mechanisms. P. falciparum generates substantial amounts of ammonia as a catabolic by-product, but lacks detoxification mechanisms. Whether this parasite-derived ammonia plays a pathogenic role in CM is presently unknown, despite its potential to cause localized brain ammonia elevation and subsequent neurotoxic effects. This article therefore, explores and proposes a potential role of parasite-derived ammonia in the pathogenesis and neuropathology of CM. A consideration of parasite-derived ammonia as a factor in CM pathogenesis provides plausible explanations of the various features observed in CM patients including how a largely intravascular parasite can cause neuronal dysfunction. It also provides a framework for rational development and testing of novel drugs targeting the parasite's ammonia handling.
Collapse
Affiliation(s)
- Sammy Kimoloi
- Department of Medical Laboratory Sciences, Masinde Muliro University of Science and Technology Kakamega, Kenya
| | - Khalid Rashid
- Biochemistry and Molecular Biology Department, Egerton University Nakuru, Kenya
| |
Collapse
|
16
|
Son HF, Kim IK, Kim KJ. Structural insights into domain movement and cofactor specificity of glutamate dehydrogenase from Corynebacterium glutamicum. Biochem Biophys Res Commun 2015; 459:387-92. [PMID: 25727019 DOI: 10.1016/j.bbrc.2015.02.109] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2015] [Accepted: 02/19/2015] [Indexed: 10/23/2022]
Abstract
Glutamate dehydrogenase (GDH) is an enzyme involved in the synthesis of amino acids by converting glutamate to α-ketoglutarate, and vice versa. To investigate the molecular mechanism of GDH, we determined a crystal structure of the Corynebacterium glutamicum-derived GDH (CgGDH) in complex with its NADP cofactor and α-ketoglutarate substrate. CgGDH functions as a hexamer, and each CgGDH monomer comprises 2 separate domains; a Rossmann fold cofactor-binding domain and a substrate-binding domain. The structural comparison between the apo- and cofactor/substrate-binding forms revealed that the CgGDH enzyme undergoes a domain movement during catalysis. In the apo-form, CgGDH exists as an open state, and upon binding of the substrate and cofactor the protein undergoes a conformation change to a closed state. Our structural study also revealed that CgGDH has cofactor specificity for NADP, but not NAD, and this was confirmed by GDH activity measurements. Residues involved in the stabilization of the NADP cofactor and the α-ketoglutarate substrate were identified, and their roles in substrate/cofactor binding were confirmed by site-directed mutagenesis experiments.
Collapse
Affiliation(s)
- Hyeoncheol Francis Son
- School of Life Sciences, KNU Creative BioResearch Group, Kyungpook National University, Daehak-ro 80, Buk-ku, Daegu 702-701, Republic of Korea
| | - Il-Kwon Kim
- Paik Kwang Industrial Company Ltd., 57 Oehang-4 Gil, Gunsan, Jellabuk-do 573-879, Republic of Korea
| | - Kyung-Jin Kim
- School of Life Sciences, KNU Creative BioResearch Group, Kyungpook National University, Daehak-ro 80, Buk-ku, Daegu 702-701, Republic of Korea.
| |
Collapse
|
17
|
Prakash P, Walvekar AS, Punekar NS, Bhaumik P. Purification, crystallization and preliminary X-ray diffraction analysis of NADP-dependent glutamate dehydrogenase from Aspergillus niger. Acta Crystallogr F Struct Biol Commun 2014; 70:1508-12. [PMID: 25372818 PMCID: PMC4231853 DOI: 10.1107/s2053230x14021499] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2014] [Accepted: 09/29/2014] [Indexed: 11/10/2022] Open
Abstract
Glutamate dehydrogenase (GDH) catalyzes the NAD-dependent or NADP-dependent oxidative deamination of L-glutamate to 2-oxoglutarate and ammonia. This important reversible reaction establishes the link between carbon and nitrogen metabolism. In this study, Aspergillus niger NADP-GDH (AnGDH) has been overexpressed and purified. Purified AnGDH, with a high specific activity of 631.1 units per milligram of protein, was crystallized and the crystal diffracted to 2.9 Å resolution using a home X-ray source. Preliminary analysis of the X-ray diffraction data showed that the crystal belonged to space group R32, with unit-cell parameters a=b=173.8, c=241.5 Å, α=β=90, γ=120°. The crystals exhibited an unusually high solvent content (83.0%) and had only one molecule in the asymmetric unit. Initial phases were obtained by molecular replacement, and model building and structure refinement of AnGDH are in progress.
Collapse
Affiliation(s)
- Prem Prakash
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai 400 076, India
| | - Adhish S. Walvekar
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai 400 076, India
| | - Narayan S. Punekar
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai 400 076, India
| | - Prasenjit Bhaumik
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai 400 076, India
| |
Collapse
|
18
|
Jain P, Chakma B, Patra S, Goswami P. Potential biomarkers and their applications for rapid and reliable detection of malaria. BIOMED RESEARCH INTERNATIONAL 2014; 2014:852645. [PMID: 24804253 PMCID: PMC3996934 DOI: 10.1155/2014/852645] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/29/2013] [Accepted: 02/11/2014] [Indexed: 12/21/2022]
Abstract
Malaria has been responsible for the highest mortality in most malaria endemic countries. Even after decades of malaria control campaigns, it still persists as a disease of high mortality due to improper diagnosis and rapidly evolving drug resistant malarial parasites. For efficient and economical malaria management, WHO recommends that all malaria suspected patients should receive proper diagnosis before administering drugs. It is thus imperative to develop fast, economical, and accurate techniques for diagnosis of malaria. In this regard an in-depth knowledge on malaria biomarkers is important to identify an appropriate biorecognition element and utilize it prudently to develop a reliable detection technique for diagnosis of the disease. Among the various biomarkers, plasmodial lactate dehydrogenase and histidine-rich protein II (HRP II) have received increasing attention for developing rapid and reliable detection techniques for malaria. The widely used rapid detection tests (RDTs) for malaria succumb to many drawbacks which promotes exploration of more efficient economical detection techniques. This paper provides an overview on the current status of malaria biomarkers, along with their potential utilization for developing different malaria diagnostic techniques and advanced biosensors.
Collapse
Affiliation(s)
- Priyamvada Jain
- Department of Biotechnology, Indian Institute of Technology Guwahati, Guwahati, Assam 781039, India
| | - Babina Chakma
- Department of Biotechnology, Indian Institute of Technology Guwahati, Guwahati, Assam 781039, India
| | - Sanjukta Patra
- Department of Biotechnology, Indian Institute of Technology Guwahati, Guwahati, Assam 781039, India
| | - Pranab Goswami
- Department of Biotechnology, Indian Institute of Technology Guwahati, Guwahati, Assam 781039, India
| |
Collapse
|
19
|
Ni Y, Wang J, Qian B, Song G, Yao X, Zhang JH. Purification and side chain selective chemical modifications of glutamate dehydrogenase from Bacillus subtilis natto. Appl Biochem Biotechnol 2014; 172:3593-605. [PMID: 24557956 DOI: 10.1007/s12010-014-0788-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2013] [Accepted: 02/10/2014] [Indexed: 10/25/2022]
Abstract
Glutamate dehydrogenase (GDH) from Bacillus subtilis natto was purified to apparent homogeneity by ammonium sulfate precipitation, ion-exchange chromatography, size exclusion chromatography, and hydroxyapatite (HA) affinity chromatography. The GDH was purified 34-fold, with a yield of 41 % of total activity and a specific activity of 34.29 U/mg proteins. The molecular weight (Mr) of was measured at 47 kDa with sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and 264 kDa with high-performance liquid chromatography (HPLC). The optimum pH and temperature for the deammoniation reaction were measured to be 7.5 and 30 °C, respectively. The active-site amino acid residues of GDH were investigated by chemical modification. The compounds 2,4,6-trinitrobenzenesulfonic acid (TNBS), phenylglyoxal (PG), and phenylmethanesulfonyl fluoride (PMSF) were used to modify lysine, arginine, and serine active site residues, respectively. After treatment with modifying reagents at concentrations of 1 mM, GDH activity fell to 10.7 % with TNBS, 83.3 % with PG, and 12.8 % with PMSF. However, with substrate protection, there was almost no loss in GDH activity following treatment with any modifying reagent. The kinetic parameters K m and V max were determined in each case. K m values for native GDH, 50 % TNBS-inactivated GDH, and 50 % PMSF-inactivated GDH were 0.037, 0.104, and 0.017 mM, respectively. V max values were 0.048, 0.022, and 0.031 mM/s, respectively. These results suggest that the active site contains one or more lysine residues that play a role in substrate binding and one or more serine residues that may maintain the enzyme conformation. However, arginine residues played less of a role in the activity of GDH.
Collapse
Affiliation(s)
- Yinyun Ni
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, 200240, China
| | | | | | | | | | | |
Collapse
|
20
|
Acharya P, Pallavi R, Chandran S, Chakravarti H, Middha S, Acharya J, Kochar S, Kochar D, Subudhi A, Boopathi AP, Garg S, Das A, Tatu U. A glimpse into the clinical proteome of human malaria parasites Plasmodium falciparum and Plasmodium vivax. Proteomics Clin Appl 2012; 3:1314-25. [PMID: 21136953 DOI: 10.1002/prca.200900090] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Malaria causes a worldwide annual mortality of about a million people. Rapidly evolving drug-resistant species of the parasite have created a pressing need for the identification of new drug targets and vaccine candidates. By developing fractionation protocols to enrich parasites from low-parasitemia patient samples, we have carried out the first ever proteomics analysis of clinical isolates of early stages of Plasmodium falciparum (Pf) and P. vivax. Patient-derived malarial parasites were directly processed and analyzed using shotgun proteomics approach using high-sensitivity MS for protein identification. Our study revealed about 100 parasite-coded gene products that included many known drug targets such as Pf hypoxanthine guanine phosphoribosyl transferase, Pf L-lactate dehydrogenase, and Plasmepsins. In addition, our study reports the expression of several parasite proteins in clinical ring stages that have never been reported in the ring stages of the laboratory-cultivated parasite strain. This proof-of-principle study represents a noteworthy step forward in our understanding of pathways elaborated by the parasite within the malaria patient and will pave the way towards identification of new drug and vaccine targets that can aid malaria therapy.
Collapse
Affiliation(s)
- Pragyan Acharya
- Department of Biochemistry, Indian Institute of Science, Bangalore, Karnataka, India
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
21
|
|
22
|
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.
Collapse
Affiliation(s)
- Janina Preuss
- Chair of Biochemistry and Molecular Biology, Interdisciplinary Research Center, Justus Liebig University, Giessen, Germany
| | | | | |
Collapse
|
23
|
Zocher K, Fritz-Wolf K, Kehr S, Fischer M, Rahlfs S, Becker K. Biochemical and structural characterization of Plasmodium falciparum glutamate dehydrogenase 2. Mol Biochem Parasitol 2012; 183:52-62. [DOI: 10.1016/j.molbiopara.2012.01.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2011] [Revised: 01/23/2012] [Accepted: 01/31/2012] [Indexed: 02/01/2023]
|
24
|
L-aspartate dehydrogenase: features and applications. Appl Microbiol Biotechnol 2011; 93:503-16. [PMID: 22120624 DOI: 10.1007/s00253-011-3730-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2011] [Revised: 10/30/2011] [Accepted: 11/14/2011] [Indexed: 10/15/2022]
Abstract
L-amino acid dehydrogenases are a group of enzymes that catalyze the reversible oxidative deamination of L-amino acids to their corresponding 2-oxoacids, using either nicotinamide adenine dinucleotide (NAD(+)) or nicotinamide adenine dinucleotide phosphate (NADP(+)) as cofactors. These enzymes have been studied widely because of their potential applications in the synthesis of amino acids for use in production of pharmaceutical peptides, herbicides and insecticides, in biosensors or diagnostic kits, and development of coenzyme regeneration systems for industrial processes. This article presents a review of the currently available data about the recently discovered amino acid dehydrogenase superfamily member L-aspartate dehydrogenase (L-AspDH), their relevant catalytic properties and speculated physiological roles, and potential for biotechnological applications. The proposed classification of L-AspDH on the basis of bioinformatic information and potential role in vivo into NadB (NAD biosynthesis-related) and non-NadB type is unique. In particular, the mesophilic non-NadB type L-AspDH is a novel group of amino acid dehydrogenases with great promise as potential industrial biocatalysts owing to their relatively high catalytic properties at room temperature. Considering that only a few L-AspDH homologs have been characterized so far, identification and prodigious enzymological research of the new members will be necessary to shed light on the gray areas pertaining to these enzymes.
Collapse
|
25
|
Storm J, Perner J, Aparicio I, Patzewitz EM, Olszewski K, Llinas M, Engel PC, Müller S. Plasmodium falciparum glutamate dehydrogenase a is dispensable and not a drug target during erythrocytic development. Malar J 2011; 10:193. [PMID: 21756354 PMCID: PMC3163627 DOI: 10.1186/1475-2875-10-193] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2011] [Accepted: 07/14/2011] [Indexed: 11/10/2022] Open
Abstract
Background Plasmodium falciparum contains three genes encoding potential glutamate dehydrogenases. The protein encoded by gdha has previously been biochemically and structurally characterized. It was suggested that it is important for the supply of reducing equivalents during intra-erythrocytic development of Plasmodium and, therefore, a suitable drug target. Methods The gene encoding the NADP(H)-dependent GDHa has been disrupted by reverse genetics in P. falciparum and the effect on the antioxidant and metabolic capacities of the resulting mutant parasites was investigated. Results No growth defect under low and elevated oxygen tension, no up- or down-regulation of a number of antioxidant and NADP(H)-generating proteins or mRNAs and no increased levels of GSH were detected in the D10Δgdha parasite lines. Further, the fate of the carbon skeleton of [13C] labelled glutamine was assessed by metabolomic studies, revealing no differences in the labelling of α-ketoglutarate and other TCA pathway intermediates between wild type and mutant parasites. Conclusions First, the data support the conclusion that D10Δgdha parasites are not experiencing enhanced oxidative stress and that GDHa function may not be the provision of NADP(H) for reductive reactions. Second, the results imply that the cytosolic, NADP(H)-dependent GDHa protein is not involved in the oxidative deamination of glutamate but that the protein may play a role in ammonia assimilation as has been described for other NADP(H)-dependent GDH from plants and fungi. The lack of an obvious phenotype in the absence of GDHa may point to a regulatory role of the protein providing glutamate (as nitrogen storage molecule) in situations where the parasites experience a limiting supply of carbon sources and, therefore, under in vitro conditions the enzyme is unlikely to be of significant importance. The data imply that the protein is not a suitable target for future drug development against intra-erythrocytic parasite development.
Collapse
Affiliation(s)
- Janet Storm
- Institute of Infection, Immunity & Inflammation, Wellcome Trust Centre for Molecular Parasitology, College of Medical, Veterinary and Life Sciences, Sir Graeme Davies Building, University of Glasgow, 120 University Place, Glasgow G12 8TA, UK
| | | | | | | | | | | | | | | |
Collapse
|
26
|
Crowther GJ, Napuli AJ, Gilligan JH, Gagaring K, Borboa R, Francek C, Chen Z, Dagostino EF, Stockmyer JB, Wang Y, Rodenbough PP, Castaneda LJ, Leibly DJ, Bhandari J, Gelb MH, Brinker A, Engels IH, Taylor J, Chatterjee AK, Fantauzzi P, Glynne RJ, Van Voorhis WC, Kuhen KL. Identification of inhibitors for putative malaria drug targets among novel antimalarial compounds. Mol Biochem Parasitol 2010; 175:21-9. [PMID: 20813141 DOI: 10.1016/j.molbiopara.2010.08.005] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2010] [Revised: 08/09/2010] [Accepted: 08/24/2010] [Indexed: 02/05/2023]
Abstract
The efficacy of most marketed antimalarial drugs has been compromised by evolution of parasite resistance, underscoring an urgent need to find new drugs with new mechanisms of action. We have taken a high-throughput approach toward identifying novel antimalarial chemical inhibitors of prioritized drug targets for Plasmodium falciparum, excluding targets which are inhibited by currently used drugs. A screen of commercially available libraries identified 5655 low molecular weight compounds that inhibit growth of P. falciparum cultures with EC(50) values below 1.25μM. These compounds were then tested in 384- or 1536-well biochemical assays for activity against nine Plasmodium enzymes: adenylosuccinate synthetase (AdSS), choline kinase (CK), deoxyuridine triphosphate nucleotidohydrolase (dUTPase), glutamate dehydrogenase (GDH), guanylate kinase (GK), N-myristoyltransferase (NMT), orotidine 5'-monophosphate decarboxylase (OMPDC), farnesyl pyrophosphate synthase (FPPS) and S-adenosylhomocysteine hydrolase (SAHH). These enzymes were selected using TDRtargets.org, and are believed to have excellent potential as drug targets based on criteria such as their likely essentiality, druggability, and amenability to high-throughput biochemical screening. Six of these targets were inhibited by one or more of the antimalarial scaffolds and may have potential use in drug development, further target validation studies and exploration of P. falciparum biochemistry and biology.
Collapse
|
27
|
Susceptibility of Plasmodium falciparum to glutamate dehydrogenase inhibitors--a possible new antimalarial target. Mol Biochem Parasitol 2010; 172:152-5. [PMID: 20399810 DOI: 10.1016/j.molbiopara.2010.04.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2010] [Revised: 03/31/2010] [Accepted: 04/08/2010] [Indexed: 11/20/2022]
Abstract
With the rapid spread of drug-resistant strains of Plasmodium falciparum, the development of new antimalarials is an urgent need. As malaria parasites live in a highly pro-oxidant environment, their anti-oxidant defences have frequently been suggested as candidate drug targets. A key point in such defences is the production of NADPH e.g. for maintaining anti-oxidant glutathione in the reduced state. Some authors have attributed this function in P. falciparum to a glutamate dehydrogenase, therefore proposed as a potential drug target. Here we show that isophthalic acid inhibits both Plasmodium GDH and bovine GDH but showing marked discrimination (70-fold lower K(i) for the parasite GDH). Isophthalic acid impairs intra-erythrocytic growth of P. falciparumin vitro whilst o-phthalic acid, not a GDH inhibitor, shows no effect. This offers hope that with careful design or thorough screening it should be possible to find inhibitors with the necessary selectivity between parasite and human GDHs.
Collapse
|
28
|
Kumar A, Sen A, Das P. Microarray based gene expression: a novel approach for identification and development of potential drug and effective vaccine against visceral Leishmaniasis. ACTA ACUST UNITED AC 2010. [DOI: 10.5138/ijaps.2010.0976.1055.01001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
|
29
|
Ma GY, Zhang JZ, Yin GR, Zhang JH, Meng XL, Zhao F. Toxoplasma gondii: proteomic analysis of antigenicity of soluble tachyzoite antigen. Exp Parasitol 2009; 122:41-6. [PMID: 19545523 DOI: 10.1016/j.exppara.2009.01.011] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2008] [Revised: 01/21/2009] [Accepted: 01/23/2009] [Indexed: 11/26/2022]
Abstract
The obligate intracellular parasite Toxoplasma gondii is an important pathogen of humans and animals. The tachyzoite of T. gondii is the main life-cycle stage that is responsible for toxoplasmosis. Study of the antigenicity of soluble tachyzoite antigen (STAg) is important for discovery of protective antigens which will aid in the detection and prevention of toxoplasmosis. At present, no complete proteome map of T. gondii STAg is established, although a large-scale whole proteomic analysis of tachyzoites is underway. In this study, 1227 protein spots of T. gondii soluble tachyzoite antigen (STAg) were fractionated by 2-dimensional electrophoresis (2-DE) at pH range 3-10. By mass spectrometry (MS) analysis, among the separated 1227 protein spots, 426 were identified by searching the Swissport and NCBI nr databases. Two hundred and thirty of these identified spots (230/426, 54%) were demonstrated to be T. gondii protein by MS. Of the 21 Toxoplasma protein spots identified by Western blot with rabbit anti-T. gondii serum, 16 had immunoregulatory functions and five had immune defense functions. Due to multiple spots for a single protein, these 16 spots represented 11 proteins: a putative protein disulfide isomerase (PDI), heat shock protein 60 (Hsp60), a pyruvate kinase (PK), a putative glutamate dehydrogenase (GDH), a coronin, a heat shock protein 70 (Hsp70), a protein kinase C receptor 1 (RACK1), a malate dehydrogenase (MDH), a major surface antigen 1 (SAG1), an uridine phosphorylase (UPase) and a peroxiredoxin (Prx). Among the identified 11 proteins, except that the antigenicity and immunogenicity of the SAG1 has been reported and antigenicity of Hsp70 has been disputed, the remaining antigenic proteins were first identified in this study. In conclusion, we obtained nine novel types of immunogenic proteins that might be potential candidates of vaccine development for toxoplasmosis, which we will confirm in later studies.
Collapse
Affiliation(s)
- Guang-Yuan Ma
- Department of Parasitology, Shanxi Medical University, No. 56 Xinjian Nan Road, Taiyuan, Shanxi 030001, PR China
| | | | | | | | | | | |
Collapse
|
30
|
Heterologous expression of plasmodial proteins for structural studies and functional annotation. Malar J 2008; 7:197. [PMID: 18828893 PMCID: PMC2567985 DOI: 10.1186/1475-2875-7-197] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2008] [Accepted: 10/01/2008] [Indexed: 11/10/2022] Open
Abstract
Malaria remains the world's most devastating tropical infectious disease with as many as 40% of the world population living in risk areas. The widespread resistance of Plasmodium parasites to the cost-effective chloroquine and antifolates has forced the introduction of more costly drug combinations, such as Coartem®. In the absence of a vaccine in the foreseeable future, one strategy to address the growing malaria problem is to identify and characterize new and durable antimalarial drug targets, the majority of which are parasite proteins. Biochemical and structure-activity analysis of these proteins is ultimately essential in the characterization of such targets but requires large amounts of functional protein. Even though heterologous protein production has now become a relatively routine endeavour for most proteins of diverse origins, the functional expression of soluble plasmodial proteins is highly problematic and slows the progress of antimalarial drug target discovery. Here the status quo of heterologous production of plasmodial proteins is presented, constraints are highlighted and alternative strategies and hosts for functional expression and annotation of plasmodial proteins are reviewed.
Collapse
|
31
|
Sahu NK, Sahu S, Kohli DV. Novel Molecular Targets for Antimalarial Drug Development. Chem Biol Drug Des 2008; 71:287-97. [DOI: 10.1111/j.1747-0285.2008.00640.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
32
|
Sherman IW. References. ADVANCES IN PARASITOLOGY 2008. [DOI: 10.1016/s0065-308x(08)00430-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|
33
|
Parodi-Talice A, Monteiro-Goes V, Arrambide N, Avila AR, Duran R, Correa A, Dallagiovanna B, Cayota A, Krieger M, Goldenberg S, Robello C. Proteomic analysis of metacyclic trypomastigotes undergoing Trypanosoma cruzi metacyclogenesis. JOURNAL OF MASS SPECTROMETRY : JMS 2007; 42:1422-1432. [PMID: 17960573 DOI: 10.1002/jms.1267] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Trypanosoma cruzi, the causative agent of the Chagas disease, has a complex life cycle alternating between replicative and noninfective forms with nonreplicative and infective forms of the parasite. Metacyclogenesis is a process that takes place in the invertebrate host, comprising morphogenetic transformation from a noninfective form to an infective form, such that parasites acquire the ability to invade human cells. We analyze here the metacyclogenesis process by 2D electrophoresis coupled to MALDI-TOF MS. A large proportion of unique proteins expressed during metacyclogenesis were observed. Interestingly, 50% of the spots were found to differ between epimastigotes and trypomastigotes. We provide a 2D map of the infective metacyclic trypomastigotes. Sixty six protein spots were successfully identified corresponding to 43 different proteins. We analyzed the expression profiles for the identified proteins along metacyclogenesis and classified them into three groups according to their maximal level of expression. We detected several isoforms for a number of proteins, some displaying differential expression during metacyclogenesis. These results suggest that posttranslational modifications may be a fundamental part of the parasite's strategy for regulating gene expression during differentiation. This study contributes to the identification of relevant proteins involved in the metacyclogenesis process. The identification and molecular characterization of these proteins will render vital information about the steps of the parasite differentiation into the infective form.
Collapse
|
34
|
Zeuthen T, Wu B, Pavlovic-Djuranovic S, Holm LM, Uzcategui NL, Duszenko M, Kun JFJ, Schultz JE, Beitz E. Ammonia permeability of the aquaglyceroporins from Plasmodium falciparum, Toxoplasma gondii and Trypansoma brucei. Mol Microbiol 2006; 61:1598-608. [PMID: 16889642 DOI: 10.1111/j.1365-2958.2006.05325.x] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Plasmodium falciparum uses amino acids from haemoglobin degradation mainly for protein biosynthesis. Glutamine, however, is mostly oxidized to 2-oxoglutarate to restore NAD(P)H + H+. In this process two molecules of ammonia are released. We determined an ammonia production of 9 mmol h(-1) per litre of infected red blood cells in the early trophozoite stage. External application of ammonia yielded a cytotoxic IC50 concentration of 2.8 mM. As plasmodia cannot metabolize ammonia it must be exported. Yet, no biochemical or genomic evidences exist that plasmodia possess classical ammonium transporters. We expressed the P. falciparum aquaglyceroporin (PfAQP) in Xenopus laevis oocytes and examined whether it may serve as an exit pathway for ammonia. We show that injected oocytes: (i) acidify the medium due to ammonia uptake, (ii) take up [14C]methylamine and [14C]formamide, (iii) swell in solution with formamide and acetamide and (iv) display an ammonia-induced NH4+-dependent clamp current. Further, a yeast strain lacking the endogenous aquaglyceroporin (Fps1) is rescued by expression of PfAQP which provides for the efflux of toxic methylamine. Ammonia permeability was similarly established for the aquaglyceroporins from Toxoplasma gondii and Trypanosoma brucei. Apparently, these aquaglyceroporins are important for the release of ammonia derived from amino acid breakdown.
Collapse
Affiliation(s)
- Thomas Zeuthen
- Nordic Centre for Water Imbalance Related Disorders, Department of Medical Physiology, The Panum Institute, University of Copenhagen, DK-2200 Copenhagen N, Denmark
| | | | | | | | | | | | | | | | | |
Collapse
|
35
|
Crooke A, Diez A, Mason PJ, Bautista JM. Transient silencing of Plasmodium falciparum bifunctional glucose-6-phosphate dehydrogenase- 6-phosphogluconolactonase. FEBS J 2006; 273:1537-46. [PMID: 16689939 DOI: 10.1111/j.1742-4658.2006.05174.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The bifunctional enzyme glucose-6-phosphate dehydrogenase-6-phosphogluconolactonase (G6PD-6PGL) found in Plasmodium falciparum has unique structural and functional characteristics restricted to this genus. This study was designed to examine the effects of RNA-mediated PfG6PD-6PGL gene silencing in cultures of P. falciparum on the expression of parasite antioxidant defense genes at the transcription level. The highest degree of G6PD-6PGL silencing achieved was 86% at the mRNA level, with a recovery to almost normal levels within 24 h, indicating only transient diminished expression of the PfG6PD-6PGL gene. PfG6PD-6PGL silencing caused arrest of the trophozoite stage and enhanced gametocyte formation. In addition, an immediate transcriptional response was shown by thioredoxin reductase suggesting that P. falciparum G6PD-6PGL plays a physiological role in the specific response of the parasite to intracellullar oxidative stress. P. falciparum transfection with an empty DNA vector also promoted intracellular stress, as determined by mRNA up-regulation of antioxidant genes. Collectively, our findings point to an important role for this enzyme in the parasite's infection cycle. The different characteristics of G6PD-6PGL with respect to its homologue in the host make it an ideal target for therapeutic strategies.
Collapse
Affiliation(s)
- Almudena Crooke
- Department of Biochemistry and Molecular Biology IV, Universidad Complutense de Madrid, Facultad de Veterinaria, Madrid, Spain
| | | | | | | |
Collapse
|