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Hashmi MA, Malik A, Arsalan A, Khan MA, Younus H. Elucidation of kinetic and structural properties of eye lens ζ-crystallin: an in vitro and in silico approach. J Biomol Struct Dyn 2023; 41:1178-1192. [PMID: 34927573 DOI: 10.1080/07391102.2021.2017351] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
The Arabian Camelus dromedarius contains significant concentration of eye lens ζ-crystallin. This enzyme is also present in other life forms including humans, however in lower catalytic amounts. The recombinant camel ζ-crystallin was expressed in the E. coli BL21 (DE3) pLysS strain and purified using HisTrap column. The Km of the enzyme for 9,10-phenanthrenequinone (9,10-PQ) substrate and NADPH cofactor was determined to be 11.66 and 50.93 µM, respectively. The Vmax for 9,10-PQ and NADPH was obtained as 23.19 and 19.98 μM min-1, respectively. The optimum activity of the purified enzyme was found to be at pH 6.0 and at 55 °C. Different physico-chemical parameters were analysed including instability index (II), aliphatic index (AI) and the GRAVY index to establish proper characterization. The sequence of the recombinant ζ-crystallin was subjected to homology modelling using SWISS-MODEL webserver followed by validation of the modelled target structure. The evaluation of the modelled ζ-crystallin was performed by several parameters including Ramachandran plot, Z-score values followed by molecular dynamics (MD) simulation. The cumulative analysis of the physico-chemical, quantitative, qualitative and the essential dynamics of simulation of ζ-crystallin and its complexes with 9,10-PQ and NADPH helped in verifying the acceptable quality and stability of the ζ-crystallin structure.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Md Amiruddin Hashmi
- Enzymology Laboratory, Interdisciplinary Biotechnology Unit, Faculty of Life Sciences, Aligarh Muslim University, Aligarh, India
| | - Ajamaluddin Malik
- Department of Biochemistry, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Abdullah Arsalan
- Enzymology Laboratory, Interdisciplinary Biotechnology Unit, Faculty of Life Sciences, Aligarh Muslim University, Aligarh, India
| | - Masood Alam Khan
- Department of Basic Health Sciences, College of Applied Medical Sciences, Qassim University, Buraydah, Saudi Arabia
| | - Hina Younus
- Enzymology Laboratory, Interdisciplinary Biotechnology Unit, Faculty of Life Sciences, Aligarh Muslim University, Aligarh, India
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Expression, purification, and biophysical characterization of recombinant MERS-CoV main (M pro) protease. Int J Biol Macromol 2022; 209:984-990. [PMID: 35452699 PMCID: PMC9017057 DOI: 10.1016/j.ijbiomac.2022.04.077] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Revised: 04/04/2022] [Accepted: 04/11/2022] [Indexed: 11/21/2022]
Abstract
MERS-CoV main protease (Mpro) is essential for the maturation of the coronavirus; therefore, considered a potential drug target. Detailed conformational information is essential to developing antiviral therapeutics. However, the conformation of MERS-CoV Mpro under different conditions is poorly characterized. In this study, MERS-CoV Mpro was recombinantly produced in E.coli and characterized its structural stability with respect to changes in pH and temperatures. The intrinsic and extrinsic fluorescence measurements revealed that MERS-CoV Mpro tertiary structure was exposed to the polar environment due to the unfolding of the tertiary structure. However, the secondary structure of MERS-CoV Mpro was gained at low pH because of charge-charge repulsion. Furthermore, differential scanning fluorometry studies of Mpro showed a single thermal transition at all pHs except at pH 2.0; no transitions were observed. The data from the spectroscopic studies suggest that the MERS-CoV Mpro forms a molten globule-like state at pH 2.0. Insilico studies showed that the covid-19 Mpro shows 96.08% and 50.65% similarity to that of SARS-CoV Mpro and MERS-CoV Mpro, respectively. This study provides a basic understanding of the thermodynamic and structural properties of MERS-CoV Mpro.
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Malik A, Khan JM, Alhomida AS, Ola MS. Modulation of the Structure and Stability of Novel Camel Lens Alpha-Crystallin by pH and Thermal Stress. Gels 2022; 8:gels8050273. [PMID: 35621572 PMCID: PMC9140948 DOI: 10.3390/gels8050273] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Revised: 04/10/2022] [Accepted: 04/22/2022] [Indexed: 02/06/2023] Open
Abstract
Alpha-crystallin protein performs structural and chaperone functions in the lens and comprises alphaA and alphaB subunits at a molar ratio of 3:1. The highly complex alpha-crystallin structure challenges structural biologists because of its large dynamic quaternary structure (300−1000 kDa). Camel lens alpha-crystallin is a poorly characterized molecular chaperone, and the alphaB subunit possesses a novel extension at the N-terminal domain. We purified camel lens alpha-crystallin using size exclusion chromatography, and the purity was analyzed by gradient (4−12%) sodium dodecyl sulfate−polyacrylamide gel electrophoresis. Alpha-crystallin was equilibrated in the pH range of 1.0 to 7.5. Subsequently, thermal stress (20−94 °C) was applied to the alpha-crystallin samples, and changes in the conformation and stability were recorded by dynamic multimode spectroscopy and intrinsic and extrinsic fluorescence spectroscopic methods. Camel lens alpha-crystallin formed a random coil-like structure without losing its native-like beta-sheeted structure under two conditions: >50 °C at pH 7.5 and all temperatures at pH 2.0. The calculated enthalpy of denaturation, as determined by dynamic multimode spectroscopy at pH 7.5, 4.0, 2.0, and 1.0 revealed that alpha-crystallin never completely denatures under acidic conditions or thermal denaturation. Alpha-crystallin undergoes a single, reversible thermal transition at pH 7.5. The thermodynamic data (unfolding enthalpy and heat capacity change) and chaperone activities indicated that alpha-crystallin does not completely unfold above the thermal transition. Camels adapted to live in hot desert climates naturally exhibit the abovementioned unique features.
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Affiliation(s)
- Ajamaluddin Malik
- Department of Biochemistry, College of Science, King Saud University, Riyadh 11451, Saudi Arabia; (A.S.A.); (M.S.O.)
- Correspondence:
| | - Javed Masood Khan
- Department of Food Science and Nutrition, Faculty of Food and Agricultural Sciences, King Saud University, Riyadh 11451, Saudi Arabia;
| | - Abdullah S. Alhomida
- Department of Biochemistry, College of Science, King Saud University, Riyadh 11451, Saudi Arabia; (A.S.A.); (M.S.O.)
| | - Mohammad Shamsul Ola
- Department of Biochemistry, College of Science, King Saud University, Riyadh 11451, Saudi Arabia; (A.S.A.); (M.S.O.)
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Malik A, Alshehri MA, Alamery SF, Khan JM. Impact of metal nanoparticles on the structure and function of metabolic enzymes. Int J Biol Macromol 2021; 188:576-585. [PMID: 34400227 DOI: 10.1016/j.ijbiomac.2021.08.073] [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: 03/15/2021] [Revised: 08/02/2021] [Accepted: 08/09/2021] [Indexed: 12/18/2022]
Abstract
The widespread use of nanoparticles raises many serious concerns about the safety and environmental impact of nanoparticles. Therefore, risk assessments of specific nanoparticles in occupational and environmental exposure are essential before their large-scale production and applications, especially in medicine and for usage in household items. In this study, the effects of five different metal nanoparticles on the structure, stability, and function of four metabolic enzymes were evaluated using various biophysical techniques. Our results show that Cu nanoparticles exhibited the most significant adverse effects on the structures, stability, and activities of all the metabolic enzymes. Zn nanoparticles caused moderate adverse effects on these enzymes. The rest of the metal (Al, Fe, and Ni) nanoparticles had a relatively lower impact on the metabolic enzymes. Our data indicated that Cu nanoparticles promote metal-catalyzed disulfide bond formation in these proteins. In summary, some metal nanoparticles can cause adverse effects on the structure, function, and stability of metabolic enzymes. In addition, metal nanoparticles may affect protein homeostasis in the cytosol or extracellular fluids.
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Affiliation(s)
- Ajamaluddin Malik
- Department of Biochemistry, College of Science, King Saud University, Riyadh, Saudi Arabia.
| | | | - Salman Freeh Alamery
- Department of Biochemistry, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Javed Masood Khan
- Department of Food Science and Nutrition, Faculty of Food and Agricultural Sciences, King Saud University, 2460, Riyadh 11451, Saudi Arabia
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Eronina TB, Mikhaylova VV, Chebotareva NA, Shubin VV, Kleymenov SY, Kurganov BI. Effect of arginine on stability and aggregation of muscle glycogen phosphorylase b. Int J Biol Macromol 2020; 165:365-374. [PMID: 32961195 DOI: 10.1016/j.ijbiomac.2020.09.101] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 09/14/2020] [Accepted: 09/14/2020] [Indexed: 11/26/2022]
Abstract
Arginine (Arg) is frequently used in biotechnology and pharmaceutics to stabilize protein preparations. When using charged ions like Arg, it is necessary to take into account their contribution to the increase in ionic strength, in addition to the effect of Arg on particular processes occurring under the conditions of constancy of ionic strength. Here, we examined contribution of ionic strength (0.15 and 0.5 M) to the effects of Arg on denaturation, thermal inactivation and aggregation of skeletal muscle glycogen phosphorylase b (Phb). Dynamic light scattering, analytical ultracentrifugation, differential scanning calorimetry, circular dichroism and enzymatic activity assay were used to assess the effects of Arg at constant ionic strength compared with the effects of ionic strength alone. We found that high ionic strength did not affect the secondary structure of Phb, but changed conformation of the protein. Such a destabilization of the enzyme causes an increase in the initial rate of aggregation and inactivation of Phb thereby affecting its denaturation. Binding of Arg causes additional changes in the protein conformation, weakening the bonds between monomers in the dimer. This causes the dimer to dissociate into monomers, which rapidly aggregate. Thus, Arg acts on these processes much stronger than just ionic strength.
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Affiliation(s)
- Tatiana B Eronina
- Bach Institute of Biochemistry, Federal Research Centre "Fundamentals of Biotechnology", Russian Academy of Sciences, Leninsky pr. 33, Moscow 119071, Russia
| | - Valeriya V Mikhaylova
- Bach Institute of Biochemistry, Federal Research Centre "Fundamentals of Biotechnology", Russian Academy of Sciences, Leninsky pr. 33, Moscow 119071, Russia
| | - Natalia A Chebotareva
- Bach Institute of Biochemistry, Federal Research Centre "Fundamentals of Biotechnology", Russian Academy of Sciences, Leninsky pr. 33, Moscow 119071, Russia
| | - Vladimir V Shubin
- Bach Institute of Biochemistry, Federal Research Centre "Fundamentals of Biotechnology", Russian Academy of Sciences, Leninsky pr. 33, Moscow 119071, Russia
| | - Sergey Y Kleymenov
- Bach Institute of Biochemistry, Federal Research Centre "Fundamentals of Biotechnology", Russian Academy of Sciences, Leninsky pr. 33, Moscow 119071, Russia; Koltzov Institute of Developmental Biology, Russian Academy of Sciences, Vavilova 26, Moscow 119991, Russia
| | - Boris I Kurganov
- Bach Institute of Biochemistry, Federal Research Centre "Fundamentals of Biotechnology", Russian Academy of Sciences, Leninsky pr. 33, Moscow 119071, Russia.
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Malik A, Almaharfi HA, Khan JM, Hisamuddin M, Alamery SF, Haq SH, Ahmed MZ. Protection of ζ-crystallin by α-crystallin under thermal stress. Int J Biol Macromol 2020; 167:289-298. [PMID: 33278428 DOI: 10.1016/j.ijbiomac.2020.11.183] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Revised: 11/25/2020] [Accepted: 11/26/2020] [Indexed: 12/12/2022]
Abstract
Cataract is one of the major causes of blindness worldwide. Several factors including post-translational modification, thermal and solar radiations promote cataractogenesis. The camel lens proteins survive very harsh desert conditions and resist cataractogenesis. The folding and aggregation mechanism of camel lens proteins are poorly characterized. The camel lens contains three ubiquitous crystallins (α-, β-, and γ-crystallin) and a novel protein (ζ-crystallin) in large amounts. In this study, a sequence similarity search of camel α-crystallin with that of other organisms showed that the camel αB-crystallin consists of an extended N-terminal domain. Our results indicate that camel α-crystallin efficiently prevented aggregation of ζ-crystallin, with or without an obligate cofactor up to 89 °C. It performed a quick and efficient holdase function irrespective of the unfolding stage or aggregation. Camel α-crystallin exhibits approximately 20% chaperone activity between 30 and 40 °C and is completely activated above 40 °C. Camel α-crystallin underwent a single reversible thermal transition without loss of β-sheet secondary structure. Intrinsic tryptophan fluorescence and ANS binding experiments revealed two transitions which corresponded to activation of its chaperone function. In contrast to earlier studies, camel α-crystallin completely protected lens proteins during thermal stress.
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Affiliation(s)
- Ajamaluddin Malik
- Department of Biochemistry, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Hajar Ahmed Almaharfi
- Department of Biochemistry, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Javed Masood Khan
- Department of Food Science and Nutrition, Faculty of Food and Agricultural Sciences, King Saud University, 2460, Riyadh 11451, Saudi Arabia
| | - Malik Hisamuddin
- Center for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, New Delhi, India
| | - Salman Freeh Alamery
- Department of Biochemistry, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Samina Hyder Haq
- Department of Biochemistry, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Mohammad Z Ahmed
- Department of Pharmacognosy, College of Pharmacy, King Saud University, Saudi Arabia
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Activation of farnesoid X receptor (FXR) induces crystallin zeta expression in mouse medullary collecting duct cells. Pflugers Arch 2020; 472:1631-1641. [PMID: 32914211 DOI: 10.1007/s00424-020-02456-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Revised: 08/24/2020] [Accepted: 08/28/2020] [Indexed: 02/05/2023]
Abstract
Crystallin zeta (CRYZ) is a phylogenetically restricted water-soluble protein and provides cytoprotection against oxidative stress via multiple mechanisms. Increasing evidence suggests that CRYZ is high abundantly expressed in the kidney where it acts as a transacting factor in increasing glutaminolysis and the Na+/K+/2Cl- cotransporter (BSC1/NKCC2) expression to help maintain acid-base balance and medullary hyperosmotic gradient. However, the mechanism by which CRYZ is regulated in the kidney remains largely uncharacterized. Here, we show that CRYZ is a direct target of farnesoid X receptor (FXR), a nuclear receptor important for renal physiology. We found that CRYZ was ubiquitously expressed in mouse kidney and constitutively expressed in the cytoplasm of medullary collecting duct cells (MCDs). In primary cultured mouse MCDs, CRYZ expression was significantly upregulated by the activation and overexpression of FXR. FXR-induced CRYZ expression was almost completely abolished in the MCD cells with siRNA-mediated FXR knockdown. Consistently, treatment with FXR agonists failed to induce CRYZ expression in the MCDs isolated from mice with global and collecting duct-specific FXR deficiency. We identified a putative FXR response element (FXRE) on the CRYZ gene promoter. The luciferase reporter and ChIP assays revealed that FXR can bind directly to the FXRE site, which was further markedly enhanced by FXR activation. Furthermore, we found CRYZ overexpression in MCDs significantly attenuated hypertonicity-induced cell death possibly via increasing Bcl-2 expression. Collectively, our findings demonstrate that CRYZ is constitutively expressed in renal medullary collecting duct cells, where it is transcriptionally controlled by FXR. Given a critical role of FXR in MCDs, CRYZ may be responsible for protective effect of FXR on the survival of MCDs under hypertonic condition during dehydration.
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Abdullah EM, Haq SH, Ahmed MA, Khan JM, Alamery SF, Malik A. Structural stability and solubility of glycated camel lens ζ-crystallin. Int J Biol Macromol 2020; 158:384-393. [PMID: 32380106 DOI: 10.1016/j.ijbiomac.2020.04.091] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Revised: 04/10/2020] [Accepted: 04/11/2020] [Indexed: 02/07/2023]
Abstract
The camel has several biochemical, physiological, and anatomical features to withstand the harsh desert climate. Camel eye lens contains a novel protein (ζ-crystallin) in bulk quantity. Previous reports suggest that non-enzymatic glycation of eye lens proteins plays an important role in the etiology of cataract. In this study, we have characterized the role of glucose, fructose, and methylglyoxal (MGO) in the glycation of camel lens ζ-crystallin. From the results obtained, it was found that MGO reacted rapidly, fructose reacted moderately, and glucose was the least reactive even after prolonged incubation (>100 days). Glycation with MGO and fructose led to changes in the structure of ζ-crystallin, while glucose had no remarkable effect. The surface hydrophobicity did not change and no aggregates or amyloid fibrils were observed in the glycated ζ-crystallin. Moreover, the secondary structure of glycated ζ-crystallin remained similar after glycation. Our results suggested that due to natural adaptation, the camel lens protein ζ-crystallin retained its structure and solubility even after glycation to perform the single known function of the lens proteins: to focus unscattered light on the retina.
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Affiliation(s)
- Ejlal Mohamed Abdullah
- Department of Biochemistry, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Samina Hyder Haq
- Department of Biochemistry, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Mohammed Asif Ahmed
- Department of Food Science and Nutrition, College of Food and Agricultural Sciences, King Saud University, 2460, Riyadh 11451, Saudi Arabia
| | - Javed Masood Khan
- Department of Food Science and Nutrition, College of Food and Agricultural Sciences, King Saud University, 2460, Riyadh 11451, Saudi Arabia
| | - Salman Freeh Alamery
- Department of Biochemistry, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Ajamaluddin Malik
- Department of Biochemistry, College of Science, King Saud University, Riyadh, Saudi Arabia.
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Lulli M, Nencioni D, Papucci L, Schiavone N. Zeta-crystallin: a moonlighting player in cancer. Cell Mol Life Sci 2020; 77:965-976. [PMID: 31563996 PMCID: PMC11104887 DOI: 10.1007/s00018-019-03301-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 09/10/2019] [Accepted: 09/16/2019] [Indexed: 12/13/2022]
Abstract
Crystallins were firstly found as structural proteins of the eye lens. To this family belong proteins, such as ζ-crystallin, expressed ubiquitously, and endowed with enzyme activity. ζ-crystallin is a moonlighting protein endowed with two main different functions: (1) mRNA binding with stabilizing activity; (2) NADPH:quinone oxidoreductase. ζ-crystallin has been clearly demonstrated to stabilize mRNAs encoding proteins involved in renal glutamine catabolism during metabolic acidosis resulting in ammoniagenesis and bicarbonate ion production that concur to compensate such condition. ζ-crystallin binds also mRNAs encoding for antiapoptotic proteins, such as Bcl-2 in leukemia cells. On the other hand, the physiological role of its enzymatic activity is still elusive. Gathering research evidences and data mined from public databases, we provide a framework where all the known ζ-crystallin properties are called into question, making it a hypothetical pivotal player in cancer, allowing cells to hijack or subjugate the acidity response mechanism to increase their ability to resist oxidative stress and apoptosis, while fueling their glutamine addicted metabolism.
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Affiliation(s)
- Matteo Lulli
- Department of Experimental and Clinical Biomedical Sciences "Mario Serio", Università Degli Studi di Firenze, Viale G.B. Morgagni, 50, Firenze, 50134, Italy.
| | - Daniele Nencioni
- Department of Experimental and Clinical Biomedical Sciences "Mario Serio", Università Degli Studi di Firenze, Viale G.B. Morgagni, 50, Firenze, 50134, Italy
| | - Laura Papucci
- Department of Experimental and Clinical Biomedical Sciences "Mario Serio", Università Degli Studi di Firenze, Viale G.B. Morgagni, 50, Firenze, 50134, Italy
| | - Nicola Schiavone
- Department of Experimental and Clinical Biomedical Sciences "Mario Serio", Università Degli Studi di Firenze, Viale G.B. Morgagni, 50, Firenze, 50134, Italy.
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Malik A, Khan JM, Alamery SF, Fouad D, Labrou NE, Daoud MS, Abdelkader MO, Ataya FS. Monomeric Camelus dromedarius GSTM1 at low pH is structurally more thermostable than its native dimeric form. PLoS One 2018; 13:e0205274. [PMID: 30303997 PMCID: PMC6179282 DOI: 10.1371/journal.pone.0205274] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Accepted: 09/21/2018] [Indexed: 01/01/2023] Open
Abstract
Glutathione S‒transferases (GSTs) are multifunctional enzymes that play an important role in detoxification, cellular signalling, and the stress response. Camelus dromedarius is well-adapted to survive in extreme desert climate and it has GSTs, for which limited information is available. This study investigated the structure-function and thermodynamic properties of a mu-class camel GST (CdGSTM1) at different pH. Recombinant CdGSTM1 (25.7 kDa) was expressed in E. coli and purified to homogeneity. Dimeric CdGSTM1 dissociated into stable but inactive monomeric subunits at low pH. Conformational and thermodynamic changes during the thermal unfolding pathway of dimeric and monomeric CdGSTM1 were characterised via a thermal shift assay and dynamic multimode spectroscopy (DMS). The thermal shift assay based on intrinsic tryptophan fluorescence revealed that CdGSTM1 underwent a two-state unfolding pathway at pH 1.0-10.0. Its Tm value varied with varying pH. Another orthogonal technique based on far-UV CD also exhibited two-state unfolding in the dimeric and monomeric states. Generally, proteins tend to lose structural integrity and stability at low pH; however, monomeric CdGSTM1 at pH 2.0 was thermally more stable and unfolded with lower van't Hoff enthalpy. The present findings provide essential information regarding the structural, functional, and thermodynamic properties of CdGSTM1 at pH 1.0-10.0.
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Affiliation(s)
- Ajamaluddin Malik
- Department of Biochemistry, Protein Research Chair, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Javed M. Khan
- Department of Food Science and Nutrition, Faculty of Food and Agricultural Sciences, King Saud University, Riyadh, Saudi Arabia
| | - Salman F. Alamery
- Department of Biochemistry, Protein Research Chair, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Dalia Fouad
- Department of Zoology, College of Science, King Saud University, Riyadh, Saudi Arabia
- Department of Zoology and Entomology, Faculty of Science, Helwan University, Ein Helwan, Cairo, Egypt
| | - Nikolaos E. Labrou
- Laboratory of Enzyme Technology, Department of Biotechnology, School of Food, Biotechnology and Development, Agricultural University of Athens, Athens, Greece
| | - Mohamed S. Daoud
- Department of Biochemistry, Protein Research Chair, College of Science, King Saud University, Riyadh, Saudi Arabia
- King Fahd Unit Laboratory, Department of Clinical and Chemical Pathology, Kasr Al-Ainy University Hospital, Cairo University, El-Manial, Cairo, Egypt
| | - Mohamed O. Abdelkader
- Department of Biochemistry, Protein Research Chair, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Farid S. Ataya
- Department of Biochemistry, Protein Research Chair, College of Science, King Saud University, Riyadh, Saudi Arabia
- Molecular Biology Department, Genetic Engineering Division, National Research Centre, Dokki, Giza, Egypt
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