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Masson P, Lushchekina S. Conformational Stability and Denaturation Processes of Proteins Investigated by Electrophoresis under Extreme Conditions. Molecules 2022; 27:6861. [PMID: 36296453 PMCID: PMC9610776 DOI: 10.3390/molecules27206861] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Revised: 10/10/2022] [Accepted: 10/10/2022] [Indexed: 11/17/2022] Open
Abstract
The functional structure of proteins results from marginally stable folded conformations. Reversible unfolding, irreversible denaturation, and deterioration can be caused by chemical and physical agents due to changes in the physicochemical conditions of pH, ionic strength, temperature, pressure, and electric field or due to the presence of a cosolvent that perturbs the delicate balance between stabilizing and destabilizing interactions and eventually induces chemical modifications. For most proteins, denaturation is a complex process involving transient intermediates in several reversible and eventually irreversible steps. Knowledge of protein stability and denaturation processes is mandatory for the development of enzymes as industrial catalysts, biopharmaceuticals, analytical and medical bioreagents, and safe industrial food. Electrophoresis techniques operating under extreme conditions are convenient tools for analyzing unfolding transitions, trapping transient intermediates, and gaining insight into the mechanisms of denaturation processes. Moreover, quantitative analysis of electrophoretic mobility transition curves allows the estimation of the conformational stability of proteins. These approaches include polyacrylamide gel electrophoresis and capillary zone electrophoresis under cold, heat, and hydrostatic pressure and in the presence of non-ionic denaturing agents or stabilizers such as polyols and heavy water. Lastly, after exposure to extremes of physical conditions, electrophoresis under standard conditions provides information on irreversible processes, slow conformational drifts, and slow renaturation processes. The impressive developments of enzyme technology with multiple applications in fine chemistry, biopharmaceutics, and nanomedicine prompted us to revisit the potentialities of these electrophoretic approaches. This feature review is illustrated with published and unpublished results obtained by the authors on cholinesterases and paraoxonase, two physiologically and toxicologically important enzymes.
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Affiliation(s)
- Patrick Masson
- Biochemical Neuropharmacology Laboratory, Kazan Federal University, Kremlievskaya Str. 18, 420111 Kazan, Russia
| | - Sofya Lushchekina
- Emanuel Institute of Biochemical Physics, Russian Academy of Sciences, Kosygin Str. 4, 119334 Moscow, Russia
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2
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Zhang X, Yin Z, Ma Z, Liang J, Zhang Z, Yao L, Chen X, Liu X, Zhang R. Shell Matrix Protein N38 of Pinctada fucata, Inducing Vaterite Formation, Extends the DING Protein to the Mollusca World. MARINE BIOTECHNOLOGY (NEW YORK, N.Y.) 2022; 24:531-541. [PMID: 35499596 DOI: 10.1007/s10126-022-10116-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Accepted: 03/11/2022] [Indexed: 06/14/2023]
Abstract
In the animal kingdom, DING proteins were only found in Chordata and Aschelminthes. At present study, a potential DING protein, matrix protein N38, was isolated and purified from the shell of Pinctada fucata. Tandem mass spectrometry analysis revealed that 14 peptide segments matched between N38 and human phosphate-binding protein (HPBP). HPBP belongs to the DING protein family and has a "DINGGG-" sequence, which is considered a "signature" of HPBP. In this study, the mass spectrometry analysis results showed that N38 had a "DIDGGG-" sequence; this structure is a mutation from the "DINGGG-" structure, which is a distinctive feature of the DING protein family. The role of N38 during calcium carbonate formation was explored through the in vitro crystallization experiment. The results of scanning electron microscopy and Raman spectrum analysis indicated that N38 induced vaterite formation. These findings revealed that N38 might regulate and participate in the precise control of the crystal growth of the shell, providing new clues for biomineralization mechanisms in P. fucata and DING protein family studies. In addition, this study helped extend the research of DING protein to the Mollusca world.
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Affiliation(s)
- Xin Zhang
- Key Laboratory of Freshwater Aquatic Genetic Resources, Shanghai Ocean University, Ministry of Agriculture, Shanghai, 201306, China
| | - Zehui Yin
- Key Laboratory of Freshwater Aquatic Genetic Resources, Shanghai Ocean University, Ministry of Agriculture, Shanghai, 201306, China
| | - Zhuojun Ma
- Chinese Academy of Fishery Sciences, Beijing, 100141, China
| | - Jian Liang
- State Key Laboratory of Plateau Ecology and Agriculture, Qinghai University, Xining, 810016, China
| | - Zhen Zhang
- Department of Biotechnology and Biomedicine, Yangtze Delta Region Institute of Tsinghua University, Zhejiang, 314000, China
| | - Liping Yao
- Department of Biotechnology and Biomedicine, Yangtze Delta Region Institute of Tsinghua University, Zhejiang, 314000, China
| | - Xia Chen
- Department of Biotechnology and Biomedicine, Yangtze Delta Region Institute of Tsinghua University, Zhejiang, 314000, China
| | - Xiaojun Liu
- Department of Biotechnology and Biomedicine, Yangtze Delta Region Institute of Tsinghua University, Zhejiang, 314000, China.
| | - Rongqing Zhang
- Protein Science laboratory of the Ministry of Education, Tsinghua University, Beijing, 100084, China.
- Department of Biotechnology and Biomedicine, Yangtze Delta Region Institute of Tsinghua University, Zhejiang, 314000, China.
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3
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Aleshin VA, Mezhenska OA, Parkhomenko YM, Kaehne T, Bunik VI. Thiamine Mono- and Diphosphate Phosphatases in Bovine Brain Synaptosomes. BIOCHEMISTRY (MOSCOW) 2021; 85:378-386. [PMID: 32564742 DOI: 10.1134/s000629792003013x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Neurodegenerative diseases are accompanied by changes in the activity of thiamine mono- and diphosphate phosphatases, but molecular identification of these mammalian enzymes is incomplete. In this work, the protein fraction of bovine brain synaptosomes displaying phosphatase activity toward thiamine derivatives was subjected to affinity chromatography on thiamine-Sepharose. Protein fractions eluted with thiamine (pH 7.4 or 5.6), NaCl, and urea were assayed for the phosphatase activity against thiamine monophosphate (ThMP), thiamine diphosphate (ThDP), and structurally similar purine nucleotides. Proteins in each fraction were identified by mass spectrometry using the SwissProt database for all organisms because of insufficient annotation of the bovine genome. Peptides of two annotated bacterial phosphatases, alkaline phosphatase L from the DING protein family and exopolyphosphatase, were identified in the acidic thiamine eluate. The abundance of peptides of alkaline phosphatase L and exopolyphosphatase in the eluted fractions correlated with ThMPase and ThDPase activities, respectively. The elution profiles of the ThMPase and ThDPase activities differed from the elution profiles of nucleotide phosphatases, thus indicating the specificity of these enzymes toward thiamine derivatives. The search for mammalian DING phosphatases in the eluates from thiamine-Sepharose revealed X-DING-CD4, mostly eluted by the acidic thiamine solution (pH 5.6). The identified exopolyphosphatase demonstrated structural similarity with apyrases possessing the ThDPase activity. The obtained results demonstrate that mammalian DING proteins and apyrases exhibit ThMPase and ThDPase activity, respectively.
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Affiliation(s)
- V A Aleshin
- Lomonosov Moscow State University, Faculty of Bioengineering and Bioinformatics, Moscow, 119991, Russia. .,Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119991, Russia
| | - O A Mezhenska
- Palladin Institute of Biochemistry, National Academy of Sciences of Ukraine, Kyiv, 01601, Ukraine
| | - Y M Parkhomenko
- Palladin Institute of Biochemistry, National Academy of Sciences of Ukraine, Kyiv, 01601, Ukraine
| | - T Kaehne
- Institute of Experimental Internal Medicine, Otto von Guericke University, Magdeburg, 39120, Germany
| | - V I Bunik
- Lomonosov Moscow State University, Faculty of Bioengineering and Bioinformatics, Moscow, 119991, Russia. .,Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119991, Russia.,Sechenov First Moscow State Medical University, Ministry of Health of the Russian Federation, Moscow, 119992, Russia
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Mortazavi H, Omidi-Ardali H, Amini SA, Saffari-Chaleshtori J, Samani KG. In vivo/ in silico insight into the effect of titanium dioxide nanoparticle on serum paraoxonase 1 activity in rat. J Biomol Struct Dyn 2021; 40:4961-4971. [PMID: 33459188 DOI: 10.1080/07391102.2020.1864662] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Serum paraoxonase1 (PON1) has special function in human body organism including the antioxidant and anti-atherogenic properties. In the present study, the effect of TiO2 nanoparticles on the activity and structure of the PON1 has been evaluated through in vivo and in silico methods. After treatments of the rats with different doses of TiO2 NPs, blood samples were collected and serum PON1 activity was measured by phenylacetate and paraoxon as substrate. In addition, the effects of TiO2 NP on enzyme structure were analyzed through Molecular dynamic (MD) simulation via Gromacs software package to obtain RMSD, RMSF, Rg, SASA, and secondary structures values. A significant reduction (p < 0.05) in arylesterase & paraoxonase activities of serum PON1 were monitored in Spectrometric assays when rats were treated with 150 and 200 mg/kg doses of TiO2 NPs. RMSD, RG, RMSF, and SASA values in the presence of TiO2 have been increased while RMSF values of the L1 and L2 loops (gate of the catalytic site) have been reduced. Moreover, Hydrogen bonds and secondary structure values of the enzyme decreased in the presence of TiO2 NP. All of these MD simulation results could indicate the instability of the PON1 structure bounded to TiO2 NP. TiO2 NP could cause a disturbance in the enzyme structure and function of PON1 based on the results. PON1 prevents oxidation of LDL and can delay atherosclerosis progression while in the presence of TiO2 NP these protective effects could be endangered.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Hessameddin Mortazavi
- Student Research Committee, Shahrekord University of Medical Sciences, Shahrekord, Iran
| | - Hossein Omidi-Ardali
- Clinical Biochemistry Research Center, Basic Health Sciences Institute, Shahrekord University of Medical Sciences, Shahrekord, Iran
| | - Seyed Asadollah Amini
- Cellular and Molecular Research Center, Basic Health Sciences Institute, Shahrekord University of Medical Sciences, Shahrekord, Iran
| | - Javad Saffari-Chaleshtori
- Clinical Biochemistry Research Center, Basic Health Sciences Institute, Shahrekord University of Medical Sciences, Shahrekord, Iran
| | - Keihan Ghatreh Samani
- Clinical Biochemistry Research Center, Basic Health Sciences Institute, Shahrekord University of Medical Sciences, Shahrekord, Iran
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Nishiya Y, Suzuki E, Ishizuka T, Kazui M, Sakurai H, Nakai D. Identification of non-P450 enzymes involved in the metabolism of new drugs: Their significance in drug interaction evaluation and prodrug disposition. Drug Metab Pharmacokinet 2020; 35:45-55. [PMID: 31926835 DOI: 10.1016/j.dmpk.2019.11.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2019] [Revised: 09/29/2019] [Accepted: 11/02/2019] [Indexed: 10/25/2022]
Affiliation(s)
- Yumi Nishiya
- Drug Metabolism & Pharmacokinetics Research Laboratories, Daiichi Sankyo Co., Ltd, Tokyo, Japan.
| | - Eiko Suzuki
- Drug Metabolism & Pharmacokinetics Research Laboratories, Daiichi Sankyo Co., Ltd, Tokyo, Japan
| | - Tomoko Ishizuka
- Clinical Pharmacology Department, Daiichi Sankyo Co., Ltd, Tokyo, Japan
| | - Miho Kazui
- Drug Metabolism & Pharmacokinetics Research Laboratories, Daiichi Sankyo Co., Ltd, Tokyo, Japan
| | - Hidetaka Sakurai
- General Administration Department, Daiichi Sankyo RD Novare Co., Ltd, Tokyo, Japan
| | - Daisuke Nakai
- Biomarker & Translational Research Department, Daiichi Sankyo Co., Ltd, Tokyo, Japan
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Araoud M, Neffeti F, Douki W, Kenani A, Najjar MF. Development of an automated method for the determination of human paraoxonase1 activity. ASIAN BIOMED 2017. [DOI: 10.5372/1905-7415.0502.027] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Abstract
Background: Human plasma paraoxonase1 (PON1) is an esterase catalyzing the hydrolysis of organophosphorus pesticides and other xenobiotics. The aims of this study were to develop a rapid method to determinate PON1 activity, evaluate some interference, and study the influence of storage temperature on PON1 activity assay.
Methods: Measurement of PON1 activity was performed for 369 samples by measuring the hydrolysis of paraoxon using a spectrophotometric method adapted on konelab 30 ⃞.
Results: The developed method facilitates the determination of PON1 activity at the rate of more than 200 samples per hour, and it is linear between 2 and 900 IU/L. Intra and inter-assay imprecision coefficients of variation were 2% and 5% respectively. PON1 activity in serum was correlated with those in heparinized plasma (r = 0.994, p < 0.001) and in plasma/EDTA (r = 0.962, p < 0.001). The mean inhibition of the PON1 activity was, by EDTA/K3, 41 ± 10 %. There was not significant PON1 activity variation after 40 days of storage at -20°C or at +4 ⃞ C. There were no substantial interferences from haemoglobin, jaundice and hyperlipidemia.
Conclusion: The developed method is reliable, reproducible, and suitable. It can also be performed on heparinized plasma for the determination of PON1 activity. Hence, it may be useful for assaying PON1 activity in several intoxications such as organophosphorus, sarin, and soman nerve agents.
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Affiliation(s)
- Manel Araoud
- Laboratory of Biochemistry, Faculty of Medicine of Monastir, University Hospital Fattouma Bourguiba Monastir, Monastir 5019, Tunisia Tunisia
- Laboratory of Biochemistry- Toxicology, University Hospital Fattouma Bourguiba Monastir, Monastir 5019, Tunisia
| | - Fadoua Neffeti
- Laboratory of Biochemistry- Toxicology, University Hospital Fattouma Bourguiba Monastir, Monastir 5019, Tunisia
| | - Wahiba Douki
- Laboratory of Biochemistry- Toxicology, University Hospital Fattouma Bourguiba Monastir, Monastir 5019, Tunisia
| | - Abderraouf Kenani
- Laboratory of Biochemistry, Faculty of Medicine of Monastir, University Hospital Fattouma Bourguiba Monastir, Monastir 5019, Tunisia
| | - Mohamed Fadhel Najjar
- Laboratory of Biochemistry- Toxicology, University Hospital Fattouma Bourguiba Monastir, Monastir 5019, Tunisia
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Amine K, Miri L, Naimi A, Saile R, El Kharrim A, Mikou A, Kettani A. Molecular Dynamics Approach in the Comparison of Wild-Type and Mutant Paraoxonase-1 Apoenzyme Form. Bioinform Biol Insights 2015; 9:129-40. [PMID: 26417201 PMCID: PMC4571988 DOI: 10.4137/bbi.s25626] [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: 03/10/2015] [Revised: 05/15/2015] [Accepted: 05/17/2015] [Indexed: 11/05/2022] Open
Abstract
There is some evidence linking the mammalian paraoxonase-1 (PON1) loops (L1 and L2) to an increased flexibility and reactivity of its active site with potential substrates. The aim of this work is to study the structural, dynamical, and functional effects of the most flexible regions close to the active site and to determine the impact of mutations on the protein. For both models, wild-type (PON1wild) and PON1 mutant (PON1mut) models, the L1 loop and Q/R and L/M mutations were constructed using MODELLER software. Molecular dynamics simulations of 20 ns at 300 K on fully modeled PON1wild and PON1mut apoenzyme have been done. Detailed analyses of the root-mean-square deviation and fluctuations, H-bonding pattern, and torsion angles have been performed. The PON1wild results were then compared with those obtained for the PON1mut. Our results show that the active site in the wild-type structure is characterized by two distinct movements of opened and closed conformations of the L1 and L2 loops. The alternating and repetitive movement of loops at specific times is consistent with the presence of 11 defined hydrogen bonds. In the PON1mut, these open-closed movements are therefore totally influenced and repressed by the Q/R and L/M mutations. In fact, these mutations seem to impact the PON1mut active site by directly reducing the catalytic core flexibility, while maintaining a significant mobility of the switch regions delineated by the loops surrounding the active site. The impact of the studied mutations on structure and dynamics proprieties of the protein may subsequently contribute to the loss of both flexibility and activity of the PON1 enzyme.
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Affiliation(s)
- Khadija Amine
- Laboratoire de Biologie et Santé (URAC34), Département de Biologie, Faculté des Sciences Ben Msik, Université Hassan II de Casablanca, Maroc
| | - Lamia Miri
- Laboratoire de Biologie et Santé (URAC34), Département de Biologie, Faculté des Sciences Ben Msik, Université Hassan II de Casablanca, Maroc
| | - Adil Naimi
- l'Association Marocaine pour la Promotion du Logiciel Libre (AMP2L), Maroc
| | - Rachid Saile
- Laboratoire de Biologie et Santé (URAC34), Département de Biologie, Faculté des Sciences Ben Msik, Université Hassan II de Casablanca, Maroc
| | - Abderrahmane El Kharrim
- Laboratoire de Mathématiques Appliquées et Systèmes d'Informations, Département de Mathématiques, Physique et Informatique, Faculté Pluridisciplinaire de Nador, Université Mohammed Premier, Oujda, Maroc. ; Grille Nationale de Calcul au Centre National de la Recherche Scientifique et Technique, Rabat, Maroc
| | - Afaf Mikou
- Laboratoire de Géosciences Appliquées à l'Ingénierie de l'Aménagement, Département de Chimie, Faculté des Sciences Ain Chock, Université Hassan II, Casablanca, Maroc
| | - Anass Kettani
- Laboratoire de Biologie et Santé (URAC34), Département de Biologie, Faculté des Sciences Ben Msik, Université Hassan II de Casablanca, Maroc
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Stabilization Studies on Bacterially Produced Human Paraoxonase 1 for Improving Its Shelf Life. Appl Biochem Biotechnol 2014; 172:3798-809. [DOI: 10.1007/s12010-014-0806-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2013] [Accepted: 02/12/2014] [Indexed: 10/25/2022]
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9
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Debord J, Bollinger JC, Harel M, Dantoine T. Temperature dependence of binding and catalysis for human serum arylesterase/paraoxonase. Biochimie 2014; 97:72-7. [DOI: 10.1016/j.biochi.2013.09.022] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2013] [Accepted: 09/24/2013] [Indexed: 11/25/2022]
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Gonzalez D, Elias M, Chabrière E. The DING Family of Phosphate Binding Proteins in Inflammatory Diseases. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2014; 824:27-32. [DOI: 10.1007/978-3-319-07320-0_4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Bajaj P, Tripathy RK, Aggarwal G, Pande AH. Characterization of human paraoxonase 1 variants suggest that His residues at 115 and 134 positions are not always needed for the lactonase/arylesterase activities of the enzyme. Protein Sci 2013; 22:1799-807. [PMID: 24123308 DOI: 10.1002/pro.2380] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2013] [Revised: 09/21/2013] [Accepted: 09/23/2013] [Indexed: 12/12/2022]
Abstract
Human paraoxonase 1 (h-PON1) hydrolyzes variety of substrates and the hydrolytic activities of enzyme can be broadly grouped into three categories; arylesterase, phosphotriesterase, and lactonase. Current models of the catalytic mechanism of h-PON1 suggest that catalytic residues H115 and H134 mediate the lactonase and arylesterase activities of the enzyme. H-PON1 is a strong candidate for the development of catalytic bioscavenger for organophosphate poisoning in humans. Recently, Gupta et al. (Nat. Chem. Biol. 2011. 7, 120) identified amino acid substitutions that significantly increased the activity of chimeric-PON1 variant (4E9) against some organophosphate nerve agents. In this study we have examined the effect of these (L69G/S111T/H115W/H134R/R192K/F222S/T332S) and other substitutions (H115W/H134R and H115W/H134R/R192K) on the hydrolytic activities of recombinant h-PON1 (rh-PON1) variants. Our results show that the substitutions resulted in a significant increase in the organophosphatase activity of all the three variants of rh-PON1 enzyme while had a variable effect on the lactonase/arylesterase activities. The results suggest that H residues at positions 115 and 134 are not always needed for the lactonase/arylesterase activities of h-PON1 and force a reconsideration of the current model(s) of the catalytic mechanism of h-PON1.
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Affiliation(s)
- Priyanka Bajaj
- Department of Biotechnology, National Institute of Pharmaceutical Education and Research (NIPER), Sector 67, S.A.S. Nagar (Mohali) 160062, Punjab, India
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Bernier F. DING proteins: numerous functions, elusive genes, a potential for health. Cell Mol Life Sci 2013; 70:3045-56. [PMID: 23743708 PMCID: PMC11113660 DOI: 10.1007/s00018-013-1377-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2013] [Revised: 04/24/2013] [Accepted: 05/16/2013] [Indexed: 10/26/2022]
Abstract
DING proteins, named after their conserved N-terminus, form an overlooked protein family whose members were generally discovered through serendipity. It is characterized by an unusually high sequence conservation, even between distantly related species, and by an outstanding diversity of activities and ligands. They all share a demonstrated capacity to bind phosphate with high affinity or at least a predicted phosphate-binding site. However, DING protein genes are conspicuously absent from databases. The many novel family members identified in recent years have confirmed that DING proteins are ubiquitous not only in animals and plants but probably also in prokaryotes. At the functional level, there is increasing evidence that they participate in many health-related processes such as cancers as well as bacterial (Pseudomonas) and viral (HIV) infections, by mechanisms that are now beginning to be understood. They thus represent potent targets for the development of novel therapeutic approaches, especially against HIV. The few genomic sequences that are now available are starting to give some clues on why DING protein genes and mRNAs are well conserved and difficult to clone. This could open a new era of research, of both fundamental and applied importance.
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Affiliation(s)
- François Bernier
- Institut de Biologie Moléculaire des Plantes du C.N.R.S., Université de Strasbourg, 28 rue Goethe, 67083, Strasbourg Cedex, France.
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Djeghader A, Aragonès G, Darbinian N, Elias M, Gonzalez D, García-Heredia A, Beltrán-Debón R, Kaminski R, Gotthard G, Hiblot J, Rull A, Rohr O, Schwartz C, Alonso-Villaverde C, Joven J, Camps J, Chabriere E. The level of DING proteins is increased in HIV-infected patients: in vitro and in vivo studies. PLoS One 2012; 7:e33062. [PMID: 22427948 PMCID: PMC3302901 DOI: 10.1371/journal.pone.0033062] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2011] [Accepted: 02/03/2012] [Indexed: 01/09/2023] Open
Abstract
DING proteins constitute an interesting family, owing to their intriguing and important activities. However, after a decade of research, little is known about these proteins. In humans, at least five different DING proteins have been identified, which were implicated in important biological processes and diseases, including HIV. Indeed, recent data from different research groups have highlighted the anti-HIV activity of some DING representatives. These proteins share the ability to inhibit the transcriptional step of HIV-1, a key step of the viral cycle that is not yet targeted by the current therapies. Since such proteins have been isolated from humans, we undertook a comprehensive study that focuses on the relationship between these proteins and HIV-infection in an infectious context. Hence, we developed a home-made ELISA for the quantification of the concentration of DING proteins in human serum. Using this method, we were able to determine the concentration of DING proteins in healthy and HIV-infected patients. Interestingly, we observed a significant increase of the concentration of DING proteins in non treated and treated HIV-infected patients compared to controls. In addition, cell cultures infected with HIV also show an increased expression of DING proteins, ruling out the possible role of antiretroviral treatment in the increase of the expression of DING proteins. In conclusion, results from this study show that the organism reacts to HIV-infection by an overexpression of DING proteins.
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Affiliation(s)
- Ahmed Djeghader
- Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes, Centre National de la Recherche Scientifique, Faculté de Médecine Aix-Marseille University, Marseille, France
| | - Gerard Aragonès
- Centre de Recerca Biomèdica, Hospital Universitari de Sant Joan, Institut d'Investigació Sanitària Pere Virgili, Universitat Rovira i Virgili, Reus, Catalonia, Spain
| | - Nune Darbinian
- Department of Neuroscience, Center for Neurovirology, Temple University School of Medicine, Philadelphia, Pennsylvania, United States of America
| | - Mikael Elias
- Department of Biological Chemistry, Weizmann Institute of Science, Rehovot, Israel
| | - Daniel Gonzalez
- Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes, Centre National de la Recherche Scientifique, Faculté de Médecine Aix-Marseille University, Marseille, France
| | - Anabel García-Heredia
- Centre de Recerca Biomèdica, Hospital Universitari de Sant Joan, Institut d'Investigació Sanitària Pere Virgili, Universitat Rovira i Virgili, Reus, Catalonia, Spain
| | - Raúl Beltrán-Debón
- Centre de Recerca Biomèdica, Hospital Universitari de Sant Joan, Institut d'Investigació Sanitària Pere Virgili, Universitat Rovira i Virgili, Reus, Catalonia, Spain
| | - Rafal Kaminski
- Department of Neuroscience, Center for Neurovirology, Temple University School of Medicine, Philadelphia, Pennsylvania, United States of America
| | - Guillaume Gotthard
- Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes, Centre National de la Recherche Scientifique, Faculté de Médecine Aix-Marseille University, Marseille, France
| | - Julien Hiblot
- Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes, Centre National de la Recherche Scientifique, Faculté de Médecine Aix-Marseille University, Marseille, France
| | - Anna Rull
- Centre de Recerca Biomèdica, Hospital Universitari de Sant Joan, Institut d'Investigació Sanitària Pere Virgili, Universitat Rovira i Virgili, Reus, Catalonia, Spain
| | - Olivier Rohr
- Institut de Parasitologie et Pathologie Tropicale, Université de Strasbourg, Strasbourg, France
| | - Christian Schwartz
- Institut de Parasitologie et Pathologie Tropicale, Université de Strasbourg, Strasbourg, France
| | | | - Jorge Joven
- Centre de Recerca Biomèdica, Hospital Universitari de Sant Joan, Institut d'Investigació Sanitària Pere Virgili, Universitat Rovira i Virgili, Reus, Catalonia, Spain
| | - Jordi Camps
- Centre de Recerca Biomèdica, Hospital Universitari de Sant Joan, Institut d'Investigació Sanitària Pere Virgili, Universitat Rovira i Virgili, Reus, Catalonia, Spain
- * E-mail: (JC); (EC)
| | - Eric Chabriere
- Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes, Centre National de la Recherche Scientifique, Faculté de Médecine Aix-Marseille University, Marseille, France
- * E-mail: (JC); (EC)
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Crossroads in the evaluation of paraoxonase 1 for protection against nerve agent and organophosphate toxicity. Toxicol Lett 2012; 210:87-94. [PMID: 22301377 DOI: 10.1016/j.toxlet.2012.01.013] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2011] [Revised: 01/13/2012] [Accepted: 01/14/2012] [Indexed: 12/22/2022]
Abstract
Human paraoxonase 1 (PON1), a 45kDa arylesterase associated with circulating high density lipoproteins (HDL), has been described as an anti-atherogenic element in cardiovascular disorders. The efficacy of PON1 as a catalytic bioscavenger against OP and CWNA toxicity has been on debate for the last few decades. Hydrolysis of various organophosphates (OPs) and chemical warfare nerve agents (CWNAs) by PON1 has been demonstrated in both in vitro and in vivo experiments. Recently, we established the protective efficacy of human and rabbit serum purified PON1 as well as human recombinant PON1 expressed in Trichoplusia ni larvae against nerve agent toxicity in guinea pigs. Exogenous administration of purified PON1 was effective in protecting against 1.2 X LCt(50) of sarin and soman administered endotracheally with microinstillation technology. However, the short half-life of exogenously administered PON1, probably due to poor association with circulating HDL, warrant alternative approaches for successful utility of PON1 in the treatment of OP/CWNA toxicity. In this mini review, we address the pros and cons of current PON1 prophylaxis and propose potential solutions for successful development of PON1 as an effective catalytic bioscavenger.
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15
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Ishizuka T, Fujimori I, Nishida A, Sakurai H, Yoshigae Y, Nakahara K, Kurihara A, Ikeda T, Izumi T. Paraoxonase 1 as a Major Bioactivating Hydrolase for Olmesartan Medoxomil in Human Blood Circulation: Molecular Identification and Contribution to Plasma Metabolism. Drug Metab Dispos 2011; 40:374-80. [DOI: 10.1124/dmd.111.041475] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
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16
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Trovaslet-Leroy M, Musilova L, Renault F, Brazzolotto X, Misik J, Novotny L, Froment MT, Gillon E, Loiodice M, Verdier L, Masson P, Rochu D, Jun D, Nachon F. Organophosphate hydrolases as catalytic bioscavengers of organophosphorus nerve agents. Toxicol Lett 2011; 206:14-23. [PMID: 21683774 DOI: 10.1016/j.toxlet.2011.05.1041] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2011] [Revised: 05/27/2011] [Accepted: 05/31/2011] [Indexed: 01/30/2023]
Abstract
Bioscavengers are molecules able to neutralize neurotoxic organophosphorus compounds (OP) before they can reach their biological target. Human butyrylcholinesterase (hBChE) is a natural bioscavenger each molecule of enzyme neutralizing one molecule of OP. The amount of natural enzyme is insufficient to achieve good protection. Thus, different strategies have been envisioned. The most straightforward consists in injecting a large dose of highly purified natural hBChE to increase the amount of bioscavenger in the bloodstream. This proved to be successful for protection against lethal doses of soman and VX but remains expensive. An improved strategy is to regenerate prophylactic cholinesterases (ChE) by administration of reactivators after exposure. But broad-spectrum efficient reactivators are still lacking, especially for inhibited hBChE. Cholinesterase mutants capable of reactivating spontaneously are another option. The G117H hBChE mutant has been a prototype. We present here the Y124H/Y72D mutant of human acetylcholinesterase; its spontaneous reactivation rate after V-agent inhibition is increased up to 110 fold. Catalytic bioscavengers, enzymes capable of hydrolyzing OP, present the best alternative. Mesophilic bacterial phosphotriesterase (PTE) is a candidate with good catalytic efficiency. Its enantioselectivity has been enhanced against the most potent OP isomers by rational design. We show that PEGylation of this enzyme improves its mean residence time in the rat blood stream 24-fold and its bioavailability 120-fold. Immunogenic issues remain to be solved. Human paraoxonase 1 (hPON1) is another promising candidate. However, its main drawback is that its phosphotriesterase activity is highly dependent on its environment. Recent progress has been made using a mammalian chimera of PON1, but we provide here additional data showing that this chimera is biochemically different from hPON1. Besides, the chimera is expected to suffer from immunogenic issues. Thus, we stress that interest for hPON1 must not fade away, and in particular, the 3D structure of the hPON1 eventually in complex with OP has to be solved.
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Affiliation(s)
- Marie Trovaslet-Leroy
- Département de Toxicologie, Institut de Recherches Biomédicales des Armées, 38700 La Tronche, France
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17
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Abstract
This article defines protein stability, emphasizes its importance and surveys some notable recent publications (2004-2008) in the field of protein stability/stabilization. Knowledge of the factors stabilizing proteins has emerged from denaturation studies and from study of thermophilic (and other extremophilic) proteins. One can enhance stability by protein engineering strategies, the judicious use of solutes and additives, immobilization, and chemical modification in solution. General protocols are set out on how to measure the kinetic thermal stability of a given protein and how to undertake chemical modification of a protein in solution.
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Affiliation(s)
- Ciarán O'Fágáin
- School of Biotechnology and National Centre for Sensor Research, Dublin City University, Dublin, Ireland.
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18
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Bayrak A, Bayrak T, Demirpençe E, Kılınç K. Differential hydrolysis of homocysteine thiolactone by purified human serum (192)Q and (192)R PON1 isoenzymes. J Chromatogr B Analyt Technol Biomed Life Sci 2010; 879:49-55. [PMID: 21123122 DOI: 10.1016/j.jchromb.2010.11.006] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2010] [Revised: 10/27/2010] [Accepted: 11/04/2010] [Indexed: 10/18/2022]
Abstract
Human serum paraoxonase 1 (PON1) is a HDL-associated enzyme that catalyzes the hydrolysis of a variety of aromatic carboxylic acid esters and several organophosphates. Recently it has been suggested that a physiological substrate of serum PON1 is homocysteine thiolactone which is a putative risk factor in atherosclerosis. In this study, human (192)Q and (192)R PON1 isoenzymes were purified from the respective phenotype human serum, using a protocol consisting of ammonium sulfate precipitation and four chromatography steps: gel filtration, ion-exchange, non-specific affinity, and a second ion-exchange. Using paraoxon as substrate, overall purification fold was found as 742 for (192)R PON1 and 590 for (192)Q PON1. The final purified enzymes were shown as single protein bands close to 45kDa on SDS-PAGE and confirmed by Western blot. Substrate kinetics were studied with phenyl acetate, paraoxon and homocysteine thiolactone. Both PON1 isoenzymes showed mixed type inhibition with phenyl acetate. K(m) values of (192)Q and (192)R PON1 for homocysteine thiolactone were 23.5mM and 22.6mM respectively. For (192)R PON1, the V(max) was 2.5-fold and k(cat)/K(m) was 2.6-fold higher than those for (192)Q PON1 when homocysteine thiolactone is used as substrate. The present data suggest that defining (192)Q and (192)R PON1 isoforms could be a good predictor and prognostic marker in the cardiovascular risk assessment.
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Affiliation(s)
- Ahmet Bayrak
- Department of Biochemistry, Hacettepe University Faculty of Medicine, 06100, Ankara, Turkey.
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19
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Ahmad S, Scott JE. Estradiol enhances cell-associated paraoxonase 1 (PON1) activity in vitro without altering PON1 expression. Biochem Biophys Res Commun 2010; 397:441-6. [PMID: 20510879 DOI: 10.1016/j.bbrc.2010.05.120] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2010] [Accepted: 05/24/2010] [Indexed: 10/19/2022]
Abstract
PON1 is a high density lipoprotein-associated enzyme that plays an important role in organophosphate detoxification and prevention of atherosclerosis. In vivo animal and human studies have indicated that estradiol (E2) supplementation enhances serum PON1 activity. In this study, we sought to determine if E2 directly up-regulates cell-associated PON1 activity in vitro and to characterize the mechanism of regulation. In vitro E2 treatment of both the human hepatoma cell line Huh7 and normal rat hepatocytes resulted in a 2- to 3-fold increase in cell-associated PON1 catalytic activity. E2 potently induced PON1 activity with average EC(50) values of 15nM for normal hepatocytes and 68nM for Huh7. The enhancement of PON1 activity by E2 was blocked by the estrogen receptor (ER) antagonist ICI 182,780 indicating that E2 was acting through the ER. The up-regulation of PON1 activity by E2 did not involve enhancement of PON1 mRNA or protein levels and did not promote secretion of PON1. Thus, E2 can enhance cell-associated PON1 activity in vitro without altering PON1 gene expression or protein level. Our data suggest that E2 may regulate the specific activity and/or stability of cell surface PON1.
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Affiliation(s)
- Syed Ahmad
- Department of Pharmaceutical Sciences, Biomanufacturing Research Institute and Technology Enterprise, North Carolina Central University, 1801 Fayetteville Street, Durham, NC 27707, USA
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20
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Integrative analytical approach by capillary electrophoresis and kinetics under high pressure optimized for deciphering intrinsic and extrinsic cofactors that modulate activity and stability of human paraoxonase (PON1). J Chromatogr B Analyt Technol Biomed Life Sci 2010; 878:1346-55. [DOI: 10.1016/j.jchromb.2009.11.027] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2009] [Revised: 11/12/2009] [Accepted: 11/13/2009] [Indexed: 11/21/2022]
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21
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Gaidukov L, Bar D, Yacobson S, Naftali E, Kaufman O, Tabakman R, Tawfik DS, Levy-Nissenbaum E. In vivo administration of BL-3050: highly stable engineered PON1-HDL complexes. BMC CLINICAL PHARMACOLOGY 2009; 9:18. [PMID: 19922610 PMCID: PMC2785756 DOI: 10.1186/1472-6904-9-18] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/01/2009] [Accepted: 11/17/2009] [Indexed: 01/03/2023]
Abstract
Background Serum paraoxonase (PON1) is a high density lipoprotein (HDL)-associated enzyme involved in organophosphate (OP) degradation and prevention of atherosclerosis. PON1 comprises a potential candidate for in vivo therapeutics, as an anti-atherogenic agent, and for detoxification of pesticides and nerve agents. Because human PON1 exhibits limited stability, engineered, recombinant PON1 (rePON1) variants that were designed for higher reactivity, solubility, stability, and bacterial expression, are candidates for treatment. This work addresses the feasibility of in vivo administration of rePON1, and its HDL complex, as a potentially therapeutic agent dubbed BL-3050. Methods For stability studies we applied different challenges related to the in vivo disfunctionalization of HDL and PON1 and tested for inactivation of PON1's activity. We applied acute, repetitive administrations of BL-3050 in mice to assess its toxicity and adverse immune responses. The in vivo efficacy of recombinant PON1 and BL-3050 were tested with an animal model of chlorpyrifos-oxon poisoning. Results Inactivation studies show significantly improved in vitro lifespan of the engineered rePON1 relative to human PON1. Significant sequence changes relative to human PON1 might hamper the in vivo applicability of BL-3050 due to adverse immune responses. However, we observed no toxic effects in mice subjected to repetitive administration of BL-3050, suggesting that BL-3050 could be safely used. To further evaluate the activity of BL-3050 in vivo, we applied an animal model that mimics human organophosphate poisoning. In these studies, a significant advantages of rePON1 and BL-3050 (>87.5% survival versus <37.5% in the control groups) was observed. Furthermore, BL-3050 and rePON1 were superior to the conventional treatment of atropine-2-PAM as a prophylactic treatment for OP poisoning. Conclusion In vitro and in vivo data described here demonstrate the potential advantages of rePON1 and BL-3050 for treatment of OP toxicity and chronic cardiovascular diseases like atherosclerosis. The in vivo data also suggest that rePON1 and BL-3050 are stable and safe, and could be used for acute, and possibly repeated treatments, with no adverse effects.
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Affiliation(s)
- Leonid Gaidukov
- Department of Biological Chemistry, Weizmann Institute of Science, Rehovot, Israel.
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22
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Berna A, Bernier F, Chabrière E, Elias M, Scott K, Suh A. For whom the bell tolls? DING proteins in health and disease. Cell Mol Life Sci 2009; 66:2205-18. [PMID: 19290474 PMCID: PMC11115607 DOI: 10.1007/s00018-009-0006-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2008] [Revised: 02/09/2009] [Accepted: 02/13/2009] [Indexed: 11/29/2022]
Abstract
DING proteins, identified mainly by their eponymous N-terminal sequences, are ubiquitous in living organisms. Amongst bacteria, they are common in pseudomonads, and have been characterised with respect to genetics and structure. They form part of a wider family of phosphate-binding proteins, with emerging roles in phosphate acquisition and pathogenicity. Many DING proteins have been isolated in eukaryotes, in which they have been associated with very diverse biological activities, often in the context of possible signalling roles. Disease states in which DING proteins have been implicated include rheumatoid arthritis, lithiasis, atherosclerosis, some tumours and tumour-associated cachexia, and bacterial and viral adherence. Complete genetic and structural characterisation of eukaryotic DING genes and proteins is still lacking, though the phosphate-binding site seems to be conserved. Whether as bacterial proteins related to bacterial pathogenicity, or as eukaryotic components of biochemical signalling systems, DING proteins require further study.
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Affiliation(s)
- Anne Berna
- Institut de Biologie Moléculaire des Plantes du CNRS, Institut de Botanique, Université de Strasbourg, 28 rue Goethe, Strasbourg Cedex, France.
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23
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Berna A, Scott K, Chabrière E, Bernier F. The DING family of proteins: ubiquitous in eukaryotes, but where are the genes? Bioessays 2009; 31:570-80. [PMID: 19360767 DOI: 10.1002/bies.200800174] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
PstS and DING proteins are members of a superfamily of secreted, high-affinity phosphate-binding proteins. Whereas microbial PstS have a well-defined role in phosphate ABC transporters, the physiological function of DING proteins, named after their DINGGG N termini, still needs to be determined. PstS and DING proteins co-exist in some Pseudomonas strains, to which they confer a highly adhesive and virulent phenotype. More than 30 DING proteins have now been purified, mostly from eukaryotes. They are often associated with infections or with dysregulation of cell proliferation. Consequently, eukaryotic DING proteins could also be involved in cell-cell communication or adherence. The ubiquitous presence in eukaryotes of proteins structurally and functionally related to bacterial virulence factors is intriguing, as is the absence of eukaryotic genes encoding DING proteins in databases. DING proteins in eukaryotes could originate from unidentified commensal or symbiotic bacteria and could contribute to essential functions. Alternatively, DING proteins could be encoded by eukaryotic genes sharing special features that prevent their cloning. Both hypotheses are discussed.
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Affiliation(s)
- Anne Berna
- Institut de Biologie Moléculaire des Plantes du CNRS, Université Louis Pasteur, Institut de Botanique, Strasbourg Cedex, France
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24
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Hu X, Jiang X, Lenz DE, Cerasoli DM, Wallqvist A. In silicoanalyses of substrate interactions with human serum paraoxonase 1. Proteins 2009; 75:486-98. [DOI: 10.1002/prot.22264] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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25
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Exploring the structural and functional stabilities of different paraoxonase-1 formulations through electrophoretic mobilities and enzyme activity parameters under hydrostatic pressure. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2009; 1794:680-8. [DOI: 10.1016/j.bbapap.2009.01.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2008] [Revised: 01/15/2009] [Accepted: 01/20/2009] [Indexed: 11/23/2022]
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26
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Graves TL, Scott JE. A high throughput serum paraoxonase assay for discovery of small molecule modulators of PON1 activity. CURRENT CHEMICAL GENOMICS 2008; 2:51-61. [PMID: 20161844 PMCID: PMC2803440 DOI: 10.2174/1875397300802010051] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/01/2008] [Revised: 10/17/2008] [Accepted: 10/20/2008] [Indexed: 01/08/2023]
Abstract
PON1 has been demonstrated to be the serum enzyme responsible for detoxifying organophosphate chemical weapons and plays a protective role against atherosclerosis. In order to identify small molecules that modulate PON1 activity in serum, we developed a high throughput kinetic absorbance assay using mouse serum and the organophosphate paraoxon. The IC(50) value obtained for the known PON1 inhibitor, 2-hydroxyquinoline, matched the value reported for purified PON1. A compound library was screened resulting in no confirmed activators, but 12 confirmed inhibitors. Seven of these hits also inhibited purified human PON1. One compound was only two-fold less potent than 2-hydroxyquinoline in the serum assay, but 10-fold more potent against purified PON1. This compound (IC(50) = 420 nM) may be useful towards a chemical probe for PON1. Therefore, this assay has utility as a high throughput assay for discovery of small molecule modulators of PON1 activity that maintain activity in serum.
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Affiliation(s)
| | - John E Scott
- Department of Pharmaceutical Sciences, Biomanufacturing Research Institute and Technology Enterprise, North Carolina Central University, 1801 Fayetteville Street, Durham, NC 27707, USA
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Stabilization of the active form(s) of human paraoxonase by human phosphate-binding protein. Biochem Soc Trans 2008; 35:1616-20. [PMID: 18031277 DOI: 10.1042/bst0351616] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
While there is a consensus that human PON1 (paraoxonase-1) has a protective role, its primary biological function remains unclear. A protective role against poisoning by organophosphates [OPs (organophosphorus compounds)] drove earlier works. Clinical interest has recently focused on a protective role of PON1 against vascular diseases. PON1 resides mainly on HDL (high-density lipoprotein) particles, and converging recent works show that both its activities and stability dramatically depend on this versatile and dynamic molecular environment. The discovery that HPBP (human phosphate-binding protein) has a firm tendency to associate with PON1 has steered new directions for characterizing PON1 functional state(s). Storage stability studies provided evidence that HPBP is involved in maintaining physiologically active PON1 conformation(s). Thermal stability studies showed that human PON1 is remarkably thermostable and that its association with HPBP strongly contributes to slowing down the denaturation rate. A hybrid PON1, displaying mutations that stabilized recombinant enzyme expressed in Escherichia coli, was shown to be more thermostable than natural human PON1. Predictably, its stability was unaffected by the presence of HPBP. Synergistic efforts on characterizing natural PON1 and rPON1 (recombinant PON1) provide information for the design of future stable mutants of PON1-based bioscavengers to be used as safe and effective countermeasures to challenge OPs. Maintaining a stable environment for such administrable human rPON1 should, at least, preserve the anti-atherogenic activity of the enzyme.
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