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Işık M, Beydemir Ş, Demir Y, Durgun M, Türkeş C, Nasır A, Necip A, Akkuş M. Benzenesulfonamide derivatives containing imine and amine groups: Inhibition on human paraoxonase and molecular docking studies. Int J Biol Macromol 2020; 146:1111-1123. [PMID: 31739032 DOI: 10.1016/j.ijbiomac.2019.09.237] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2019] [Revised: 09/09/2019] [Accepted: 09/24/2019] [Indexed: 11/19/2022]
Abstract
Sulfonamides known as inhibitors of many metabolic enzymes have been widely used as antimicrobial drugs for a long time. In the present study, we investigated in vitro inhibitory activities of benzenesulfonamide derivatives on human paraoxonase-I (hPON1). For this aim, PON1 was purified from human serum with a specific activity of 2603.57 EU/mg and 8.34% yield using simple chromatographic methods. The various concentrations of early-synthesized sixteen sulfonamide derivatives were tested on the paraoxonase activity. Ki values of compounds were found in the range of 0.28-357.70 µM. Compound H4 had the highest inhibitory activity on hPON1 as competitive. Estimated structure-activity relationship (SAR) for compounds was done based on different substituents and their positions in the compounds. Besides, the molecular docking analysis of compound H4 was performed to understand the binding interactions on the active site of the enzyme. According to these experimental results, compound H4 was a potential inhibitor of PON1.
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Affiliation(s)
- Mesut Işık
- Department of Pharmacy Services, Health Services Vocational School, Harran University, 63300 Şanlıurfa, Turkey
| | - Şükrü Beydemir
- Department of Biochemistry, Faculty of Pharmacy, Anadolu University, 26470 Eskişehir, Turkey.
| | - Yeliz Demir
- Department of Pharmacy Services, Nihat Delibalta Göle Vocational High School, Ardahan University, Ardahan 75700, Turkey
| | - Mustafa Durgun
- Department of Chemistry, Faculty of Arts and Sciences, Harran University, 63290 Şanlıurfa, Turkey
| | - Cüneyt Türkeş
- Department of Biochemistry, Faculty of Pharmacy, Erzincan Binali Yıldırım University, 24100 Erzincan, Turkey
| | - Abdul Nasır
- Department of Molecular Science and Technology, Ajou University, Suwon 443-749, South Korea
| | - Adem Necip
- Department of Pharmacy Services, Health Services Vocational School, Harran University, 63300 Şanlıurfa, Turkey
| | - Musa Akkuş
- Department of Chemistry, Faculty of Sciences, Atatürk University, 25240 Erzurum, Turkey
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Demir Y, Balcı N, Gürbüz M. Differential effects of selective serotonin reuptake inhibitors on paraoxonase-1 enzyme activity: An in vitro study. Comp Biochem Physiol C Toxicol Pharmacol 2019; 226:108608. [PMID: 31422163 DOI: 10.1016/j.cbpc.2019.108608] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2019] [Revised: 08/09/2019] [Accepted: 08/14/2019] [Indexed: 10/26/2022]
Abstract
Paraoxonase-I (PON1) is a calcium-dependent hydrolytic enzyme, plays an important role in most antioxidant properties related to high-density lipoprotein (HDL). Antidepressant drugs are commonly employed in treatment of mood disorders and anxiety treatment. In this study, human serum PON1 was purified using simple reproducible procedures and the effects of some antidepressant drugs on its activity were determined. It was found that mirtazapine, aripiprazole, escitalopram, and risperidone exhibited potential inhibitory properties on the purified PON1 activity with IC50 values in the range of 115.50-231.00 μM and Ki values in the range of 41.66 ± 4.27 μM-276.36 ± 35.28 μM. Both risperidone and escitalopram inhibited PON1 activity competitively, while both aripiprazole and mirtazapine inhibited PON1 activity non-competitively. Chlorpromazine did not affect PON1 activity. Usage of drugs with significant biological activity may be hazardous in some cases.
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Affiliation(s)
- Yeliz Demir
- Department of Chemistry, Faculty of Science, Atatürk University, 25240 Erzurum, Turkey; Department of Pharmacy Services, Nihat Delibalta Göle Vocational High School, Ardahan University, 75700, Ardahan, Turkey.
| | - Neslihan Balcı
- Department of Chemistry, Faculty of Science, Atatürk University, 25240 Erzurum, Turkey
| | - Mahmut Gürbüz
- Gaziantep Islahiye State Hospital, 27800 Gaziantep, Turkey
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Rhoads MK, Hauk P, Gupta V, Bookstaver ML, Stephens K, Payne GF, Bentley WE. Modification and Assembly of a Versatile Lactonase for Bacterial Quorum Quenching. Molecules 2018; 23:E341. [PMID: 29415497 PMCID: PMC6016966 DOI: 10.3390/molecules23020341] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Revised: 01/23/2018] [Accepted: 01/23/2018] [Indexed: 01/05/2023] Open
Abstract
This work sets out to provide a self-assembled biopolymer capsule activated with a multi-functional enzyme for localized delivery. This enzyme, SsoPox, which is a lactonase and phosphotriesterase, provides a means of interrupting bacterial communication pathways that have been shown to mediate pathogenicity. Here we demonstrate the capability to express, purify and attach SsoPox to the natural biopolymer chitosan, preserving its activity to "neutralize" long-chain autoinducer-1 (AI-1) communication molecules. Attachment is shown via non-specific binding and by engineering tyrosine and glutamine affinity 'tags' at the C-terminus for covalent linkage. Subsequent degradation of AI-1, in this case N-(3-oxododecanoyl)-l-homoserine lactone (OdDHL), serves to "quench" bacterial quorum sensing (QS), silencing intraspecies communication. By attaching enzymes to pH-responsive chitosan that, in turn, can be assembled into various forms, we demonstrate device-based flexibility for enzyme delivery. Specifically, we have assembled quorum-quenching capsules consisting of an alginate inner core and an enzyme "decorated" chitosan shell that are shown to preclude bacterial QS crosstalk, minimizing QS mediated behaviors.
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Affiliation(s)
- Melissa K Rhoads
- Institute for Bioscience and Biotechnology Research (IBBR), University of Maryland, College Park, MD 20742, USA.
- Fischell Department of Bioengineering, University of Maryland, College Park, MD 20742, USA.
| | - Pricila Hauk
- Institute for Bioscience and Biotechnology Research (IBBR), University of Maryland, College Park, MD 20742, USA.
- Fischell Department of Bioengineering, University of Maryland, College Park, MD 20742, USA.
| | - Valerie Gupta
- Fischell Department of Bioengineering, University of Maryland, College Park, MD 20742, USA.
| | - Michelle L Bookstaver
- Fischell Department of Bioengineering, University of Maryland, College Park, MD 20742, USA.
| | - Kristina Stephens
- Institute for Bioscience and Biotechnology Research (IBBR), University of Maryland, College Park, MD 20742, USA.
- Fischell Department of Bioengineering, University of Maryland, College Park, MD 20742, USA.
| | - Gregory F Payne
- Institute for Bioscience and Biotechnology Research (IBBR), University of Maryland, College Park, MD 20742, USA.
- Fischell Department of Bioengineering, University of Maryland, College Park, MD 20742, USA.
| | - William E Bentley
- Institute for Bioscience and Biotechnology Research (IBBR), University of Maryland, College Park, MD 20742, USA.
- Fischell Department of Bioengineering, University of Maryland, College Park, MD 20742, USA.
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Gençer N, Yavuz E. An alternative purification method for human serum paraoxonase 1 and its interaction with methidathion. Arch Physiol Biochem 2017; 123:159-164. [PMID: 28276711 DOI: 10.1080/13813455.2017.1279632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
In this study, an alternative purification method for human Paraoxonase 1 (hPON1) enzyme was developed using two-step procedures, namely ammonium sulphate precipitation and Sepharose-4B-L-tyrosine-1-aminoanthracene hydrophobic interaction chromatography. SDS-polyacrylamide gel electrophoresis of the enzyme indicates a single band with an apparent MW of 43 kDa. The enzyme was purified 674-fold with a yield of 16%. Furthermore, we examined the in vitro effect of methidathion on the enzyme activity to understand the better inhibitory properties of the compound. Methidathion is a highly toxic insecticide used to control a broad spectrum of agricultural insect and mite pests. IC50 value was found to be 0.130 mM for the pesticide. Methidathion showed a competitive inhibition with Ki of 0.119 mM for paraoxon.
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Affiliation(s)
- Nahit Gençer
- a Department of Chemistry , Faculty of Art and Science, Balikesir University , Balikesir , Turkey
| | - Emre Yavuz
- a Department of Chemistry , Faculty of Art and Science, Balikesir University , Balikesir , Turkey
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Barman DN, Haque MA, Islam SMA, Yun HD, Kim MK. Cloning and expression of ophB gene encoding organophosphorus hydrolase from endophytic Pseudomonas sp. BF1-3 degrades organophosphorus pesticide chlorpyrifos. Ecotoxicol Environ Saf 2014; 108:135-141. [PMID: 25062445 DOI: 10.1016/j.ecoenv.2014.06.023] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2014] [Revised: 06/08/2014] [Accepted: 06/19/2014] [Indexed: 06/03/2023]
Abstract
Chlorpyrifos is an organophosphate pesticide that has adverse effect on animals and plants. We isolated endophytic bacterial strain, Pseudomonas sp. BF1-3, from balloon flower root which can hydrolyze chlorpyrifos. A gene (ophB) encoding a protein involved in chlorpyrifos degradation from this strain was cloned into Escherichia coli DH5α for confirming enzyme activity. After sequencing, total 1024bp nucleotide sequences were found in the open reading frame of ophB. The chlorpyrifos degradation patterns by E. coli DH5α (ophB) were observed. During incubation in minimal salt (M9) medium supplemented with chlorpyrifos (100mgL(-1)), the E. coli DH5α harboring ophB degraded about 97% initial chlorpyrifos (100mgL(-1)) and accumulated 86mgL(-1) 3,5,6-trichloro-2-pyridinol (TCP) within 9 days. In addition, optical density (OD) of E. coli DH5α (ophB) culture at 600nm was increased from 0.172 to 1.118 within 2 days of inoculation in the chlorpyrifos supplemented M9 medium. The estimated molecular weight of purified OphB protein was determined to be 31.4kDa by SDS-PAGE. The OphB enzyme was most active at pH 8 and an optimal temperature around 35°C. These results indicate that endophytic bacteria are supposed to be useful for biological control of environments contaminated with pesticides.
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Affiliation(s)
- Dhirendra Nath Barman
- Division of Applied Life Science (BK21 Plus Program), Gyeongsang National University, Chinju 660-701, Republic of Korea
| | - Md Azizul Haque
- Division of Applied Life Science (BK21 Plus Program), Gyeongsang National University, Chinju 660-701, Republic of Korea
| | - Shah Md Asraful Islam
- Department of Plant Pathology, Patuakhali Science and Technology University, Dumki, Patuakhali 8602, Bangladesh
| | - Han Dae Yun
- Division of Applied Life Science (BK21 Plus Program), Gyeongsang National University, Chinju 660-701, Republic of Korea; Research Institute of Agriculture and Life Science, Gyeongsang National University, Chinju 660-701, Republic of Korea
| | - Min Keun Kim
- Gyeongsangnam-do Agricultural Research and Extension Service, Chinju 660-360, Republic of Korea.
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Dedeoğlu N, Arslan M, Erzengin M. Purification of Holstein bull semen paraoxonase 1 (PON1) by hydrophobic interaction chromatography and investigation of its inhibition kinetics by heavy metals. Biol Trace Elem Res 2014; 158:29-35. [PMID: 24563030 DOI: 10.1007/s12011-014-9916-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2013] [Accepted: 02/05/2014] [Indexed: 02/05/2023]
Abstract
In this study, paraoxonase 1 (PON1; EC 3.1.8.1) was purified from bull semen, and some characteristics of the enzyme were investigated. In vitro inhibition effect of some heavy metals, including Cu(2+), Mn(2+), Cd(2+), Zn(2+), Ni(2+), and Pb(2+), on the activity of the purified enzyme was also investigated. The purification of bull semen PON1 procedure was composed of two steps: ammonium sulfate precipitation and Sepharose-4B-L-tyrosine-1-naphthylamine hydrophobic interaction chromatography. The enzyme, having a specific activity of 288 EU/mg proteins, was purified 22.67-fold with a yield of 89 %. Sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis of the purified enzyme showed the presence of a single band with an apparent MW of 66 kDa. The V max and K M values for the paraoxon substrate were determined as 100 EU and 8.0 × 10(-5) M, respectively. The inhibitory effects of different heavy metals on PON1 activity were determined by using the paraoxon as a substrate. The results showed that all the metals, except for Cd(2+), inhibited the PON1 enzyme activity in a concentration-dependent fashion. IC50 values of Cu(2+), Mn(2+), Zn(2+), Ni(2+), and Pb(2+) were found as 2.59 × 10(-3), 1.17 × 10(-3), 42.74 × 10(-3), 99.10 × 10(-3), 48.80 × 10(-3) mM, respectively. Conversely, Cd(2+) increased the bull semen PON1 enzyme activity. The present study has demonstrated that Cu(2+), Mn(2+), Zn(2+), Ni(2+), and Pb(2+) are serious toxic metals, which are able to increase the risk of oxidative stress development and a subsequent decrease of semen quality.
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Affiliation(s)
- Nurcan Dedeoğlu
- Faculty of Science and Letters, Department of Chemistry, Balikesir University, 10100, Balikesir, Turkey
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Gotthard G, Hiblot J, Gonzalez D, Chabrière E, Elias M. Crystallization and preliminary X-ray diffraction analysis of the organophosphorus hydrolase OPHC2 from Pseudomonas pseudoalcaligenes. Acta Crystallogr Sect F Struct Biol Cryst Commun 2013; 69:73-6. [PMID: 23295492 PMCID: PMC3539709 DOI: 10.1107/s174430911205049x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2012] [Accepted: 12/11/2012] [Indexed: 02/02/2023]
Abstract
Enzymes that are capable of degrading neurotoxic organophosphorus compounds are of increasing interest because of the lack of efficient and clean methods for their removal. Recently, a novel organophosphorus hydrolase belonging to the metallo-β-lactamase superfamily was identified and isolated from the mesophilic bacterium Pseudomonas pseudoalcaligenes. This enzyme, named OPHC2, is endowed with significant thermal and pH stability, making it an appealing candidate for engineering studies to develop an efficient organophosphorus biodecontaminant. Combined with biochemical studies, structural information will help decipher the catalytic mechanism of organophosphorus hydrolysis by OPHC2 and identify the residues involved in its substrate specificity. Here, the expression, purification, crystallization and X-ray data collection at 2.1 Å resolution of OPHC2 are presented.
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Affiliation(s)
- Guillaume Gotthard
- Aix Marseille Université, URMITE, UM63, CNRS 7278, IRD 198, Inserm 1095, 13005 Marseille, France
| | - Julien Hiblot
- Aix Marseille Université, URMITE, UM63, CNRS 7278, IRD 198, Inserm 1095, 13005 Marseille, France
| | - Daniel Gonzalez
- Aix Marseille Université, URMITE, UM63, CNRS 7278, IRD 198, Inserm 1095, 13005 Marseille, France
| | - Eric Chabrière
- Aix Marseille Université, URMITE, UM63, CNRS 7278, IRD 198, Inserm 1095, 13005 Marseille, France
- Département de Toxicologie, Institut de Recherches Biomédicales des Armées-CRSSA, BP 87, 38702 La Tronche CEDEX, France
| | - Mikael Elias
- Biological Chemistry, Weizmann Institute of Science, Rehovot 76100, Israel
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Otto TC, Scott JR, Kauffman MA, Hodgins SM, Ditargiani RC, Hughes JH, Sarricks EP, Saturday GA, Hamilton TA, Cerasoli DM. Identification and characterization of novel catalytic bioscavengers of organophosphorus nerve agents. Chem Biol Interact 2012; 203:186-90. [PMID: 23041042 DOI: 10.1016/j.cbi.2012.09.009] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2012] [Revised: 09/14/2012] [Accepted: 09/18/2012] [Indexed: 11/18/2022]
Abstract
In an effort to discover novel catalytic bioscavengers of organophosphorus (OP) nerve agents, cell lysates from a diverse set of bacterial strains were screened for their capacity to hydrolyze the OP nerve agents VX, VR, and soman (GD). The library of bacterial strains was identified using both random and rational approaches. Specifically, two representative strains from eight categories of extremophiles were chosen at random. For the rational approach, the protein sequence of organophosphorus hydrolase (OPH) from Brevundimonas diminuta was searched against a non-redundant protein database using the Basic Local Alignment Search Tool to find regions of local similarity between sequences. Over 15 protein sequences with significant sequence similarity to OPH were identified from a variety of bacterial strains. Some of these matches were based on predicted protein structures derived from bacterial genome sequences rather than from bona fide proteins isolated from bacteria. Of the 25 strains selected for nerve agent testing, three bacterial strains had measurable levels of OP hydrolase activity. These strains are Ammoniphilus oxalaticus, Haloarcula sp., and Micromonospora aurantiaca. Lysates from A. oxalaticus had detectable hydrolysis of VR; Haloarcula sp. had appreciable hydrolysis of VX and VR, whereas lysates from M. aurantiaca had detectable hydrolysis of VR and GD.
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Affiliation(s)
- Tamara C Otto
- Neurobehavioral Toxicology Branch, Analytical Toxicology Division, US Army Medical Research Institute of Chemical Defense, 3100 Ricketts Point Road, Aberdeen Proving Ground, MD 21010-5400, United States.
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Abstract
Mammalian paraoxonases (PONs) are a unique, highly conserved family of calcium-dependent esterases consisting of PON1, PON2, and PON3. The PONs can hydrolyze the lactone ring of a range of N-acyl-L: -homoserine lactone (AHL) quorum sensing signaling molecules, rendering them inactive. This chapter describes a method that utilizes high-performance liquid chromatography analysis with UV detection for determining the rate of AHL hydrolysis in cell lysates, tissue homogenates, serum, and with purified proteins. Also described are the techniques used to prepare cell culture lysates and tissue homogenates for analysis and the use of class-specific enzyme inhibitors to determine the contribution of PONs to AHL hydrolysis in the samples.
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Affiliation(s)
- John F Teiber
- Division of Epidemiology, Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX, USA
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Ekinci D, Beydemir S. Purification of PON1 from human serum and assessment of enzyme kinetics against metal toxicity. Biol Trace Elem Res 2010; 135:112-20. [PMID: 19727574 DOI: 10.1007/s12011-009-8500-0] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2009] [Accepted: 08/10/2009] [Indexed: 10/20/2022]
Abstract
Paraoxonase-1 (PON1) is an organophosphate hydrolyser enzyme which has also antioxidant properties in metabolism. Due to its crucial functions, inhibition of the enzyme is undesirable and very dangerous. PON1 enzyme activity should not be altered in any case. Inhibitory investigations of this enzyme are therefore important and useful. Metal toxicology of enzymes has become popular in the recent years. Here, we report the in vitro inhibitory effects of some metal ions, including Pb(+2), Cr(+2), Fe(+2), and Zn(+2), on the activity of human serum PON1 (hPON1; EC 3.1.8.1.). For this purpose, we purified the enzyme from human serum and analyzed the alterations in the enzyme activity in the presence of metal ions. The results show that metal ions exhibit inhibitory effects on hPON1 at low concentrations with IC (50) values ranging from 0.838 to 7.410 mM. Metal ions showed different inhibition mechanisms: lead and iron were competitive, chrome was noncompetitive, and zinc was uncompetitive. Lead was determined to be the most effective inhibitor.
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Affiliation(s)
- Deniz Ekinci
- Department of Chemistry, Science Faculty, Biochemistry Division, Atatürk University, 25240, Erzurum, Turkey
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Nguyen SD, Sok DE. Effect of 3,4-dihydroxyphenylalanine on Cu2+-induced Inactivation of HDL-associated Paraoxonase1 and Oxidation of HDL; Inactivation of Paraoxonase1 Activity Independent of HDL Lipid Oxidation. Free Radic Res 2009; 38:969-76. [PMID: 15621715 DOI: 10.1080/10715760400000943] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Paraoxonasel (PON1), one of HDL-asssociated antioxidant proteins, is known to be sensitive to oxidative stress. Here, the effect of endogenous reducing compounds on Cu(2+)-mediated inactivation of PON1 was examined. Cu(2+)-mediated inactivation of PON1 was enhanced remarkably by catecholamines, but not by uric acid or homocysteine. Furthermore, catecholamines such as 3,4-dihydroxyphenylalanine (DOPA), dopamine or norepinephrine were more effective than caffeic acid or pyrocatechol in promoting Cu(2+)-mediated inactivation of PON1, suggesting the importance of dihydroxybenzene group as well as amino group. DOPA at relatively low concentrations showed a concentration-dependent inactivation of PON1 in a concert with Cu2+, but not Fe2+. The DOPA/Cu(2+)-induced inactivation of PON1 was prevented by catalase, but not hydroxyl radical scavengers, consistent with Cu(2+)-catalyzed oxidation. A similar result was also observed when HDL-associated PON1 (HDL-PON1) was exposed to DOPA/Cu2+. Separately, it was found that DOPA at low concentrations (1-6 microM) acted as a pro-oxidant by enhancing Cu(2+)-induced oxidation of HDL, while it exhibited an antioxidant action at > or = 10 microM. In addition, Cu(2+)-oxidized HDL lost the antioxidant action against LDL oxidation. Meanwhile, the role of DOPA/Cu(2+)-oxidized HDL differed according to DOPA concentration; HDL oxidized with Cu2+ in the presence of DOPA (60 or 120 microM) maintained antioxidant activity of native HDL, in contrast to an adverse effect of DOPA at 3 or 6 microM. These data indicate that DOPA at micromolar level may act as a pro-oxidant in Cu(2+)-induced inactivation of PON1 as well as oxidation of HDL. Also, it is proposed that the oxidative inactivation of HDL-PON1 is independent of HDL oxidation.
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Affiliation(s)
- Su Duy Nguyen
- College of Pharmacy, Chungnam National University, Yuseong-Ku, Taejon 305-764, South Korea
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Chu XY, Wu NF, Deng MJ, Tian J, Yao B, Fan YL. Expression of organophosphorus hydrolase OPHC2 in Pichia pastoris: Purification and characterization. Protein Expr Purif 2006; 49:9-14. [PMID: 16769224 DOI: 10.1016/j.pep.2006.03.013] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2005] [Revised: 03/18/2006] [Accepted: 03/21/2006] [Indexed: 11/24/2022]
Abstract
Organophosphorus hydrolase is able to hydrolyze phosphoester bonds and reduce the toxicity of organophosphorus compounds. In this work, recombinant organophosphorus hydrolase OPHC2 was successfully produced by Pichia pastoris at a high expression level (approximately 5.5 g/L) using 3 L high-cell-density fermentation. The expression level is higher than those produced in other expression systems. The results of the SDS-PAGE and the Western blot analyses showed a major 36 kDa polypeptide band, which was the same size as that from the original bacteria, Pseudomonas pseudoalcaligenes C2-1. The expressed enzyme was recovered from the culture supernatant and purified by a single-step purification procedure with a recovery rate of 72.78%. The main physiochemical features of the recombinant OPHC2, including its optimum temperature and pH for the reaction, its temperature and pH stability, and its sensitivity to some metal ions and chemical reagents, were also characterized. With methyl parathion as a substrate, the optimum temperature and pH for enzyme activity are 65 degrees C and pH 9.0, respectively. It also shows good thermal and pH stability.
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Affiliation(s)
- Xiao-Yu Chu
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China
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Mee-Hie Cho C, Mulchandani A, Chen W. Functional analysis of organophosphorus hydrolase variants with high degradation activity towards organophosphate pesticides. Protein Eng Des Sel 2006; 19:99-105. [PMID: 16423845 DOI: 10.1093/protein/gzj007] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Organophosphorus hydrolase (OPH, also known as phosphotriesterase) is a bacterial enzyme that is capable of degrading a wide range of neurotoxic organophosphate nerve agents. Directed evolution has been used to generate one variant (22A11) with up to 25-fold improved hydrolysis of methyl parathion. Surprisingly, this variant also degraded all other substrates (paraoxon, parathion and coumaphos) tested 2- to 10-fold faster. Since only one mutation (H257Y) is directly located in the active site, site-directed mutagenesis and saturation mutagenesis were used to identify the role of the other distal substitutions (A14T, A80V, K185R, H257Y, I274N) on substrate specificity and activity. Sequential site-directed mutagenesis indicated that K185R and I274N are the most important substitutions, leading to an improvement not only in the hydrolysis of methyl parathion but also the overall hydrolysis rate of all other substrates tested. Using structural modeling, these two mutations were shown to favor the formation of hydrogen bonds with nearby residues, resulting in structural changes that could alter the overall substrate hydrolysis.
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Affiliation(s)
- Catherine Mee-Hie Cho
- Department of Chemical and Environmental Engineering, University of California, Riverside, 92521, USA
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Sinan S, Kockar F, Arslan O. Novel purification strategy for human PON1 and inhibition of the activity by cephalosporin and aminoglikozide derived antibiotics. Biochimie 2006; 88:565-74. [PMID: 16600468 DOI: 10.1016/j.biochi.2005.12.004] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2004] [Accepted: 12/19/2005] [Indexed: 01/31/2023]
Abstract
Human serum paraoxonase (PON1, EC 3.1.8.1.) is a high-density lipid (HDL)-associated, calcium-dependent enzyme; its physiological substrates are not known. In this study, a new purification strategy for human PON1 enzyme was developed using two-step procedures, namely ammonium sulfate precipitation and sepharose-4B-l-tyrosine-1-napthylamine hydrophobic interaction chromatography. SDS-polyacrylamide gel electrophoresis of the enzyme indicates a single band with an apparent MW of 43 kDa. Overall purification rate of our method was found 227-fold. The V(max) and K(m) of the purified enzyme were determined 227.27 EU and 4.16 mM, respectively. The in vitro effects of commonly used antibiotics, namely gentamycin sulfate and cefazolin sodium was also investigated on the purified human serum PON1 enzyme and human liver PON1 enzyme from human hepatoma cell (HepG2). Gentamycin sulfate and cefazolin sodium caused a dose- and time-dependent decrease on PON1 activity in HepG2 cells. Moreover, gentamycin sulfate and cefazolin sodium were effective inhibitors on purified human serum PON1 activity with IC(50) of 0.887 and 0.0084 values, respectively. The kinetics of interaction of gentamycin sulfate and cefazolin sodium with the purified human serum PON1 indicated a different inhibition pattern. Cefazolin sodium showed a competitive inhibition with K(i) of 0.012+/-0.00065 mM. However, Gentamycin sulfate was inhibited in non-competitive manner with K(i) of 0.026+/-0.015. In order to determine the inhibition statue of these drugs on a living system, the effects of same antibiotics on PON1 enzyme activity of mouse serum PON1 and liver PON1 were investigated in vivo. Gentamycin sulfate (3.2 mg/kg) and cefazolin sodium (106.25 mg/kg) leads to the significant decrease in mouse serum PON1 after 2, 4, 6 h and 2, 4 h drug administration, respectively. Cefazolin sodium did not exhibit any inhibition effect for the liver PON1, in vivo.
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Affiliation(s)
- Selma Sinan
- Department of Biology, Faculty of Art and Science, Balikesir University, 10100 Balikesir, Turkey.
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15
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Contreras-Martel C, Carpentier P, Morales R, Renault F, Chesne-Seck ML, Rochu D, Masson P, Fontecilla-Camps JC, Chabrière E. Crystallization and preliminary X-ray diffraction analysis of human phosphate-binding protein. Acta Crystallogr Sect F Struct Biol Cryst Commun 2006; 62:67-9. [PMID: 16511265 PMCID: PMC2150935 DOI: 10.1107/s1744309105041461] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2005] [Accepted: 12/11/2005] [Indexed: 11/11/2022]
Abstract
Human phosphate-binding protein (HPBP) was serendipitously discovered by crystallization and X-ray crystallography. HPBP belongs to a eukaryotic protein family named DING that is systematically absent from the genomic database. This apoprotein of 38 kDa copurifies with the HDL-associated apoprotein paraoxonase (PON1) and binds inorganic phosphate. HPBP is the first identified transporter capable of binding phosphate ions in human plasma. Thus, it may be regarded as a predictor of phosphate-related diseases such as atherosclerosis. In addition, HPBP may be a potential therapeutic protein for the treatment of such diseases. Here, the purification, detergent-exchange protocol and crystallization conditions that led to the discovery of HPBP are reported.
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Affiliation(s)
- Carlos Contreras-Martel
- Laboratoire de Cristallogenèse et Cristallographie des Protéines, Institut de Biologie Structurale J.-P. Ebel, 38027 Grenoble, France
| | - Philippe Carpentier
- Laboratoire de Cristallogenèse et Cristallographie des Protéines, Institut de Biologie Structurale J.-P. Ebel, 38027 Grenoble, France
| | - Renaud Morales
- Laboratoire de Cristallogenèse et Cristallographie des Protéines, Institut de Biologie Structurale J.-P. Ebel, 38027 Grenoble, France
| | - Frédérique Renault
- Unité d’Enzymologie, Département de Toxicologie, Centre de Recherches du Service de Santé des Armées, 38702 La Tronche, France
| | - Marie-Laure Chesne-Seck
- Laboratoire de Cristallographie Macromoléculaire, Institut de Biologie Structurale J.-P. Ebel, 38027 Grenoble, France
| | - Daniel Rochu
- Unité d’Enzymologie, Département de Toxicologie, Centre de Recherches du Service de Santé des Armées, 38702 La Tronche, France
| | - Patrick Masson
- Unité d’Enzymologie, Département de Toxicologie, Centre de Recherches du Service de Santé des Armées, 38702 La Tronche, France
| | - Juan Carlos Fontecilla-Camps
- Laboratoire de Cristallogenèse et Cristallographie des Protéines, Institut de Biologie Structurale J.-P. Ebel, 38027 Grenoble, France
| | - Eric Chabrière
- Unité d’Enzymologie, Département de Toxicologie, Centre de Recherches du Service de Santé des Armées, 38702 La Tronche, France
- Laboratoire de Cristallographie et Modélisation des Matériaux Minéraux et Biologiques, CNRS–Université Henri Poincaré, 54506 Vandoeuvre-lès-Nancy, France
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Sinan S, Kockar F, Gencer N, Yildirim H, Arslan O. Amphenicol and macrolide derived antibiotics inhibit paraoxonase enzyme activity in human serum and human hepatoma cells (HepG2) in vitro. Biochemistry (Moscow) 2006; 71:46-50. [PMID: 16457617 DOI: 10.1134/s0006297906010068] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Human serum paraoxonase (hPON1) was separately purified by ammonium sulfate precipitation and hydrophobic interaction chromatography. The in vitro effects of commonly used antibiotics, namely clarithromycin and chloramphenicol, on purified human serum paraoxonase enzyme activity (serum hPON1) and human hepatoma (HepG2) cell paraoxonase enzyme activity (liver hPON1) were determined. Serum hPON1 and liver hPON1 were determined using paraoxon as a substrate and IC(50) values of these drugs exhibiting inhibition effects were found from graphs of hydratase activity (%) by plotting concentration of the drugs. We determined that chloramphenicol and clarithromycin were effective inhibitors of serum hPON1.
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Affiliation(s)
- S Sinan
- Balikesir University, Science and Art Faculty, Department of Biology/Biochemistry Section, Balikesir, Turkey
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17
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Zhu J, Ze Y, Zhang C, Zang Y, Lu H, Chu P, Sun M, Qin J. High-level expression of recombinant human paraoxonase 1 Q in silkworm larvae (Bombyx mori). Appl Microbiol Biotechnol 2005; 72:103-108. [PMID: 16331452 DOI: 10.1007/s00253-005-0246-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2005] [Revised: 10/26/2005] [Accepted: 11/01/2005] [Indexed: 11/30/2022]
Abstract
Human serum paraoxonase 1 (hPON1) belongs to a family of enzymes that catalyze the hydrolysis of a broad range of esters and lactones. Although the very first identification of hPON1 might have been as a calcium-dependent paraoxonase/arylesterase, PON1 is in fact a lactonase associated with high-density lipoprotein and strongly stimulated by apoA-I. PON1 hydrolyzes various organophosphates, including insecticides and nerve gases. PON1 also plays a key role in prevention of atherosclerosis. Mediation of cholesterol efflux from macrophage is a key in vivo function of PON1. In present study, the hPON1 Q gene was cloned into baculovirus transfer vector pVL1392 and expressed in silkworm expression system. The rhPON1 Q presented two bands with every near molecular weight of about 40 and 43 kDa according to sodium dodecyl sulphate-polyacrylamide gel electrophoresis and Western blotting analysis. The expression level was up to 1,256 mg/L in haemolymph, about 50 times as high as that from BmN cells (24.8 mg/L). After purified by two chromatography steps (DEAE-Sepharose and HiTrap Chelating HP), the purity of rhPON1 Q was up to 90%, and the enzymatic properties are similar to serum hPON1.
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Affiliation(s)
- Jie Zhu
- School of Life Science and State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing, 210093, People's Republic of China
| | - Yuguan Ze
- School of Life Science and State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing, 210093, People's Republic of China
| | - Chi Zhang
- School of Life Science and State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing, 210093, People's Republic of China
| | - Yuhui Zang
- School of Life Science and State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing, 210093, People's Republic of China
| | - Haiqin Lu
- School of Life Science and State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing, 210093, People's Republic of China
| | - Ping Chu
- School of Life Science and State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing, 210093, People's Republic of China
| | - Manji Sun
- Institute of Pharmacology and Toxicology, Academy of Military Medical Sciences, Beijing, 100850, People's Republic of China
| | - Junchuan Qin
- School of Life Science and State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing, 210093, People's Republic of China.
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Kiderlen D, Eyer P, Worek F. Formation and disposition of diethylphosphoryl-obidoxime, a potent anticholinesterase that is hydrolyzed by human paraoxonase (PON1). Biochem Pharmacol 2005; 69:1853-67. [PMID: 15876422 DOI: 10.1016/j.bcp.2005.04.003] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2005] [Revised: 04/01/2005] [Accepted: 04/07/2005] [Indexed: 11/26/2022]
Abstract
The potential of pyridinium-4-aldoximes, such as obidoxime, to reactivate diethylphosphorylated acetylcholinesterases is not fully exploited due to the inevitable formation of phosphoryloximes (POX) with high anticholinesterase activity. Mono(diethylphosphoryl) obidoxime (DEP-obidoxime) was isolated for the first time showing remarkable stability under physiological conditions (half-life 13.5min; pH 7.1; 37 degrees C). The half-life was considerably extended to 20h at 0 degrees C, which facilitated the preparation and allowed isolation by HPLC. The structure was confirmed by mass spectrometry and the degradation pattern. DEP-obidoxime decomposed by an elimination reaction forming the intermediate nitrile that hydrolyzed mainly into the pyridone and cyanide. The intermediates were prepared and confirmed by mass spectroscopy. DEP-Obidoxime was an extremely potent inhibitor of human acetylcholinesterase approaching a second-order rate constant of 10(9)M(-1)min(-1) (pH 7.4; 37 degrees C). The nitrile and the pyridone were still good reactivators. In the presence of human plasma DEP-obidoxime was hydrolyzed into parent obidoxime. Calcium-dependence and sensitivity towards chelators, substitution pattern by other divalent cations and protein-modifying agents all pointed to human paraoxonase (hPON1) as the responsible protein with POX-hydrolase activity. Subjects, probably belonging to the homozygous (192)arginine subtype, were virtually devoid of POX-hydrolase activity while a highly purified hPON1 of the homozygous (192)glutamine subtype exhibited particularly high POX-hydrolase activity. Two parathion-poisoned patients with high and low POX-hydrolase activity responded well and poorly, respectively, to obidoxime treatment although the former patient had higher plasma paraoxon levels than the poor responder. Hence, the POX-hydrolase associated PON1 subtype may be another contributor that modulates pyridinium-4-aldoxime effectiveness.
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Affiliation(s)
- D Kiderlen
- Walther-Straub-Institute of Pharmacology and Toxicology, Ludwig-Maximilians-University, Goethestrasse 33, 80336 Munich, Germany
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Togawa T, Mukai Y, Ohata K, Suzuki T, Tanabe S. Measurement of homocysteine thiolactone hydrolase activity using high-performance liquid chromatography with fluorescence detection and polymorphisms of paraoxonase in normal human serum. J Chromatogr B Analyt Technol Biomed Life Sci 2005; 819:67-72. [PMID: 15797522 DOI: 10.1016/j.jchromb.2005.01.023] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2004] [Accepted: 01/24/2005] [Indexed: 10/25/2022]
Abstract
We developed a non-radioactive and sensitive assay method for measurement of the HTL hydrolase (HTLase) activity in biological samples, using OPA as a fluorescent post-labeling agent, l-homocysteine thiolactone (L-HTL) as the substrate, and HPLC to achieve rapid and selective separation of the substrate and product. The method was applied to measure the activity of HTLase in human, rabbit, rat and mouse serum samples. In addition, the correlation between the serum HTLase activity and PON1 polymorphisms in Japanese subjects was also investigated. The serum HTLase activity in humans, as determined by measurement of the enzyme activity in 22 subjects, was found to be in the range of 0.89-2.06 nmol/min mg protein, with a mean activity of 1.44 nmol/min mg protein.
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Affiliation(s)
- Tadayasu Togawa
- Department of Analytical Biochemistry, Meiji Pharmaceutical University, 2-522-1 Noshio, Kiyose-Shi, Tokyo 204-8588, Japan.
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Teiber JF, Draganov DI, La Du BN. Purified human serum PON1 does not protect LDL against oxidation in the in vitro assays initiated with copper or AAPH. J Lipid Res 2004; 45:2260-8. [PMID: 15342686 DOI: 10.1194/jlr.m400213-jlr200] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Purified serum paraoxonase (PON1) had been shown to attenuate the oxidation of LDL in vitro. We critically reevaluated the antioxidant properties of serum PON1 in the in vitro assays initiated with copper or the free radical generator 2,2'-azobis-2-amidinopropane hydrochloride (AAPH). The antioxidant activity of different purified PON1 preparations did not correlate with their arylesterase (AE), lactonase, or phospholipase A2 activities or with the amounts of detergent or protein. Dialysis of three of these preparations resulted in a 30-40% loss of their AE activities but in a complete loss of their antioxidant activities. We also followed the distribution of the antioxidant activity during human serum PON1 purification by two purification methods. The antioxidant activity of the anion-exchange chromatography fractions did not copurify with PON1 using either method and could largely be accounted for by the "antioxidant" activity of the detergent present. In conclusion, using the copper or AAPH in vitro assays, no PON1-mediated antioxidant activity was detected, suggesting that the removal of PON1 from its natural environment may impair its antioxidative activity and that this assay with highly purified PON1 may be an inappropriate method with which to study the antioxidative properties of the enzyme.
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Affiliation(s)
- John F Teiber
- Department of Pharmacology, University of Michigan Medical School, Ann Arbor, MI, USA
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21
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Nguyen SD, Sok DE. Oxidative inactivation of paraoxonase1, an antioxidant protein and its effect on antioxidant action. Free Radic Res 2003; 37:1319-30. [PMID: 14753756] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/28/2023]
Abstract
Paraoxonase1 (PON1), one of antioxidant proteins to protect low density lipoprotein (LDL) from the oxidation, is known to lose its activity in the oxidative environment. Here, we attempted to elucidate the possible mechanisms for the oxidative inactivation of PON1, and to examine the capability of hydroxyl radicals-inactivated PON1 to prevent against LDL oxidation. Of various oxidative systems, the ascorbate/Cu2+ system was the most potent in inactivating the purified PON1 (PON1) as well as HDL-bound PON1 (HDL-PON1). In contrast to a limited inactivation by Fe2+ (2.0 microM), the inclusion of Cu2+ (0.1-1.0 microM) remarkably enhanced the inactivation of PON1 in the presence of ascorbate (0.5mM). A similar result was also obtained with the inactivation of HDL-PON1. The inactivation of PON1 by ascorbate/Cu2+ was pevented by catalase, but not general hydroxyl radical scavengers, supporting inactivation. In addition, Cu2+ alone inactivated PON1, either soluble or HDL-bound, by different mechanisms, concentration-dependent. Separately, there was a reverse relationship between the inactivation of PON1 and its preventive action against LDL oxidation during Cu2+-induced oxidation of LDL. Noteworthy, ascorbate/Cu2+-inactivated PON1, which was charaterized by the partial loss of histidine residues, expressed a lower protection against Cu2+-induced LDL oxidation, compared to native PON1. Based on these results, it is proposed that metal-catalyzed oxidation may be a primary factor to cause the decrease of HDL-associated PON1 activity under oxidative stress, and radicals-induced inactivation of PON1 may lead to the decrease in its antioxidant action against LDL oxidation.
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Affiliation(s)
- Su Duy Nguyen
- College of Pharmacy, Chungnam National University, Yuseong-Ku, Taejon 305-764, South Korea
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Fokine A, Morales R, Contreras-Martel C, Carpentier P, Renault F, Rochu D, Chabriere E. Direct phasing at low resolution of a protein copurified with human paraoxonase (PON1). Acta Crystallogr D Biol Crystallogr 2003; 59:2083-7. [PMID: 14646065 DOI: 10.1107/s0907444903017682] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2003] [Accepted: 08/08/2003] [Indexed: 11/10/2022]
Abstract
In this paper, the low-resolution structure of a previously unknown protein copurified with human paraoxonase (PON1) is reported. The structure of this protein was very difficult to solve using classical crystallographic methods. Progress was made using a new phasing method based on topological analysis. From the experimental point of view, this method has the advantage of requiring only a simple low-resolution X-ray data set. The program used and the different steps of the data-processing and phasing procedure are described. The results provided an insight into the failure of previous molecular-replacement attempts. The low-resolution shape of the protein which was presented with confidence is compared with and confirmed by the structure at 1.8 A solved subsequently using classical methods. This work shows that this direct-phasing method could be used systematically in difficult cases: it provides low-resolution structural information comparable with that obtainable by electron microscopy.
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Affiliation(s)
- A Fokine
- Laboratoire de Cristallographie et Modélisation des Matériaux Minéraux et Biologiques, Unité Mixte de Recherche 7036 CNRS, Université Henri Poincaré Nancy I, BP 239, 54506 Vandoeuvre-lès-Nancy, France
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Rodrigo L, Gil F, Hernandez AF, Lopez O, Pla A. Identification of paraoxonase 3 in rat liver microsomes: purification and biochemical properties. Biochem J 2003; 376:261-8. [PMID: 12946270 PMCID: PMC1223763 DOI: 10.1042/bj20030732] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2003] [Revised: 08/21/2003] [Accepted: 08/28/2003] [Indexed: 11/17/2022]
Abstract
Three paraoxonase genes (PON1, PON2 and PON3) have been described so far in mammals. Although considerable information is available regarding PON1, little is known about PON2 and PON3. PON3 has been isolated recently from rabbit serum [Draganov, Stetson, Watson, Billecke and La Du (2000) J. Biol. Chem. 275, 33435-33442] and liver [Ozols (1999) Biochem. J. 338, 265-275]. In the present study, we have identified the presence of PON3 in rat liver microsomes and a method for the purification to homogeneity is presented. PON3 has been purified 177-fold to apparent homogeneity with a final specific activity of 461 units/mg using a method consisting of seven steps: solubilization of the microsomal fraction, hydroxyapatite adsorption, chromatography on DEAE-Sepharose CL-6B, non-specific affinity chromatography on Cibacron Blue 3GA, two DEAE-cellulose steps and a final affinity chromatography on concanavalin A-Sepharose. SDS/PAGE of the final preparation indicated a single protein-staining band with an apparent molecular mass of 43 kDa. The isolated protein was identified by nanoelectrospray MS. Internal amino acid sequences of several peptides were determined and compared with those of human, rabbit and mouse PON3, showing a high similarity. Some biochemical properties of PON3 were also studied, including optimum pH, K(m) and heat and pH stability.
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Affiliation(s)
- Lourdes Rodrigo
- Departamento de Medicina Legal y Toxicología, Facultad de Medicina, Avda, Madrid 11, Granada 18071, Spain
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