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Rougé S, Genetet S, Leal Denis MF, Dussiot M, Schwarzbaum PJ, Ostuni MA, Mouro-Chanteloup I. Mechanosensitive Pannexin 1 Activity Is Modulated by Stomatin in Human Red Blood Cells. Int J Mol Sci 2022; 23:ijms23169401. [PMID: 36012667 PMCID: PMC9409209 DOI: 10.3390/ijms23169401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Revised: 08/11/2022] [Accepted: 08/18/2022] [Indexed: 11/16/2022] Open
Abstract
Pannexin 1 (PANX1) was proposed to drive ATP release from red blood cells (RBCs) in response to stress conditions. Stomatin, a membrane protein regulating mechanosensitive channels, has been proposed to modulate PANX1 activity in non-erythroid cells. To determine whether stomatin modulates PANX1 activity in an erythroid context, we have (i) assessed the in situ stomatin-PANX1 interaction in RBCs, (ii) measured PANX1-stimulated activity in RBCs expressing stomatin or from OverHydrated Hereditary Stomatocytosis (OHSt) patients lacking stomatin, and in erythroid K562 cells invalidated for stomatin. Proximity Ligation Assay coupled with flow imaging shows 27.09% and 6.13% positive events in control and OHSt RBCs, respectively. The uptake of dyes 5(6)-Carboxyfluorescein (CF) and TO-PRO-3 was used to evaluate PANX1 activity. RBC permeability for CF is 34% and 11.8% in control and OHSt RBCs, respectively. PANX1 permeability for TO-PRO-3 is 35.72% and 18.42% in K562 stom+ and stom− clones, respectively. These results suggest an interaction between PANX1 and stomatin in human RBCs and show a significant defect in PANX1 activity in the absence of stomatin. Based on these results, we propose that stomatin plays a major role in opening the PANX1 pore by being involved in a caspase-independent lifting of autoinhibition.
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Affiliation(s)
- Sarah Rougé
- Université Paris Cité and Université des Antilles, INSERM U1134, BIGR, F-75014 Paris, France
| | - Sandrine Genetet
- Université Paris Cité and Université des Antilles, INSERM U1134, BIGR, F-75014 Paris, France
| | - Maria Florencia Leal Denis
- Instituto de Química y Fisico-Química Biológicas “Prof. Alejandro C. Paladini”, UBA, CONICET, Facultad de Farmacia y Bioquímica, 1113 Buenos Aires, Argentina
| | - Michael Dussiot
- Université Paris Cité, INSERM U1163, IMAGINE, F-75015 Paris, France
| | - Pablo Julio Schwarzbaum
- Instituto de Química y Fisico-Química Biológicas “Prof. Alejandro C. Paladini”, UBA, CONICET, Facultad de Farmacia y Bioquímica, 1113 Buenos Aires, Argentina
| | - Mariano Anibal Ostuni
- Université Paris Cité and Université des Antilles, INSERM U1134, BIGR, F-75014 Paris, France
| | - Isabelle Mouro-Chanteloup
- Université Paris Cité and Université des Antilles, INSERM U1134, BIGR, F-75014 Paris, France
- Correspondence:
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Leal Denis MF, Alvarez HA, Lauri N, Alvarez CL, Chara O, Schwarzbaum PJ. Dynamic Regulation of Cell Volume and Extracellular ATP of Human Erythrocytes. PLoS One 2016; 11:e0158305. [PMID: 27355484 PMCID: PMC4927150 DOI: 10.1371/journal.pone.0158305] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2016] [Accepted: 06/13/2016] [Indexed: 11/18/2022] Open
Abstract
Introduction The peptide mastoparan 7 (MST7) triggered in human erythrocytes (rbcs) the release of ATP and swelling. Since swelling is a well-known inducer of ATP release, and extracellular (ATPe), interacting with P (purinergic) receptors, can affect cell volume (Vr), we explored the dynamic regulation between Vr and ATPe. Methods and Treatments We made a quantitative assessment of MST7-dependent kinetics of Vr and of [ATPe], both in the absence and presence of blockers of ATP efflux, swelling and P receptors. Results In rbcs 10 μM MST7 promoted acute, strongly correlated changes in [ATPe] and Vr. Whereas MST7 induced increases of 10% in Vr and 190 nM in [ATPe], blocking swelling in a hyperosmotic medium + MST7 reduced [ATPe] by 40%. Pre-incubation of rbcs with 10 μM of either carbenoxolone or probenecid, two inhibitors of the ATP conduit pannexin 1, reduced [ATPe] by 40–50% and swelling by 40–60%, while in the presence of 80 U/mL apyrase, an ATPe scavenger, cell swelling was prevented. While exposure to 10 μM NF110, a blocker of ATP-P2X receptors mediating sodium influx, reduced [ATPe] by 48%, and swelling by 80%, incubation of cells in sodium free medium reduced swelling by 92%. Analysis and Discussion Results were analyzed by means of a mathematical model where ATPe kinetics and Vr kinetics were mutually regulated. Model dependent fit to experimental data showed that, upon MST7 exposure, ATP efflux required a fast 1960-fold increase of ATP permeability, mediated by two kinetically different conduits, both of which were activated by swelling and inactivated by time. Both experimental and theoretical results suggest that, following MST7 exposure, ATP is released via two conduits, one of which is mediated by pannexin 1. The accumulated ATPe activates P2X receptors, followed by sodium influx, resulting in cell swelling, which in turn further activates ATP release. Thus swelling and P2X receptors constitute essential components of a positive feedback loop underlying ATP-induced ATP release of rbcs.
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Affiliation(s)
- M. Florencia Leal Denis
- Instituto de Química y Fisicoquímica Biológicas “Prof. A. C. Paladini”, Universidad de Buenos Aires, CONICET, FFyB, Buenos Aires, Argentina
| | - H. Ariel Alvarez
- Instituto de Física de Líquidos y Sistemas Biológicos (IFLYSIB), CONICET, Universidad Nacional de La Plata (UNLP), La Plata, Argentina
| | - Natalia Lauri
- Instituto de Química y Fisicoquímica Biológicas “Prof. A. C. Paladini”, Universidad de Buenos Aires, CONICET, FFyB, Buenos Aires, Argentina
| | - Cora L. Alvarez
- Instituto de Química y Fisicoquímica Biológicas “Prof. A. C. Paladini”, Universidad de Buenos Aires, CONICET, FFyB, Buenos Aires, Argentina
| | - Osvaldo Chara
- Instituto de Física de Líquidos y Sistemas Biológicos (IFLYSIB), CONICET, Universidad Nacional de La Plata (UNLP), La Plata, Argentina
- Center for Information Services and High Performance Computing (ZIH), Technische Universität Dresden (TUD), Dresden, Germany
| | - Pablo J. Schwarzbaum
- Instituto de Química y Fisicoquímica Biológicas “Prof. A. C. Paladini”, Universidad de Buenos Aires, CONICET, FFyB, Buenos Aires, Argentina
- * E-mail:
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Leal Denis MF, Incicco JJ, Espelt MV, Verstraeten SV, Pignataro OP, Lazarowski ER, Schwarzbaum PJ. Kinetics of extracellular ATP in mastoparan 7-activated human erythrocytes. Biochim Biophys Acta Gen Subj 2013; 1830:4692-707. [PMID: 23742824 DOI: 10.1016/j.bbagen.2013.05.033] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2013] [Revised: 04/24/2013] [Accepted: 05/20/2013] [Indexed: 01/26/2023]
Abstract
BACKGROUND The peptide mastoparan 7 (MST7) stimulated ATP release in human erythrocytes. We explored intra- and extracellular processes governing the time-dependent accumulation of extracellular ATP (i.e., ATPe kinetics). METHODS Human erythrocytes were treated with MST7 in the presence or absence of two blockers of pannexin 1. ATPe concentration was monitored by luciferin-luciferase based real-time luminometry. RESULTS Exposure of human erythrocytes to MST7 led to an acute increase in [ATPe], followed by a slower increase phase. ATPe kinetics reflected a strong activation of ATP efflux and a low rate of ATPe hydrolysis by ectoATPase activity. Enhancement of [ATPe] by MST7 required adhesion of erythrocytes to poly-D-lysin-coated coverslips, and correlated with a 31% increase of cAMP and 10% cell swelling. However, when MST7 was dissolved in a hyperosmotic medium to block cell swelling, ATPe accumulation was inhibited by 49%. Erythrocytes pre-exposure to 10μM of either carbenoxolone or probenecid, two blockers of pannexin 1, exhibited a partial reduction of ATP efflux. Erythrocytes from pannexin 1 knockout mice exhibited similar ATPe kinetics as those of wild type mice erythrocytes exposed to pannexin 1 blockers. CONCLUSIONS MST7 induced release of ATP required either cell adhesion or strong activation of cAMP synthesis. Part of this release required cell swelling. Kinetic analysis and a data driven model suggested that ATP efflux is mediated by two ATP conduits displaying different kinetics, with one conduit being fully blocked by pannexin 1 blockers. GENERAL SIGNIFICANCE Kinetic analysis of extracellular ATP accumulation from human erythrocytes and potential effects on microcirculation.
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Anwar-Mohamed A, Abdelhamid G, Amara IEA, El-Kadi AOS. Differential modulation of cytochrome P450 1a1 by arsenite in vivo and in vitro in C57BL/6 mice. Free Radic Biol Med 2013; 58:52-63. [PMID: 23369756 DOI: 10.1016/j.freeradbiomed.2013.01.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/12/2012] [Revised: 01/14/2013] [Accepted: 01/22/2013] [Indexed: 10/27/2022]
Abstract
Heavy metals, typified by arsenite (As(III)), have been implicated in altering the carcinogenicity of aryl hydrocarbon receptor (AhR) ligands, typified by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), by modulating the induction of the Cyp1a1 enzyme, but the mechanism remains unresolved. In this study, the effects of As(III) on Cyp1a1 expression and activity were investigated in C57BL/6 mouse livers and isolated hepatocytes. For this purpose, C57BL/6 mice were injected intraperitoneally with As(III) (12.5 mg/kg) in the absence and presence of TCDD (15 μg/kg) for 6 and 24 h. Furthermore, isolated hepatocytes from C57BL/6 mice were treated with As(III) (1, 5, and 10 μM) in the absence and presence of TCDD (1 nM) for 3, 6, 12, and 24 h. At the in vivo level, As(III) decreased the TCDD-mediated induction of Cyp1a1 mRNA at 6h while potentiating its mRNA, protein, and catalytic activity levels at 24 h. At the in vitro level, As(III) decreased the TCDD-mediated induction of Cyp1a1 mRNA in a concentration- and time-dependent manner. Moreover, As(III) decreased the TCDD-mediated induction of Cyp1a1 protein and catalytic activity levels at 24 h. Interestingly, As(III) increased the serum hemoglobin (Hb) levels in animals treated for 24 h. Upon treatment of isolated hepatocytes with Hb alone, there was an increase in the nuclear accumulation of AhR and AhR-dependent luciferase activity. Furthermore, Hb potentiated the TCDD-induced AhR-dependent luciferase activity. Importantly, when isolated hepatocytes were treated for 5h with As(III) in the presence of TCDD and the medium was then replaced with new medium containing Hb, there was potentiation of the TCDD-mediated effect. Taken together, these results demonstrate for the first time that there is a differential modulation of the TCDD-mediated induction of Cyp1a1 by As(III) in C57BL/6 mouse livers and isolated hepatocytes. Thus, this study implicates Hb as an in vivo-specific modulator.
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Affiliation(s)
- Anwar Anwar-Mohamed
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, AB, Canada T6G 2E1
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Abdelhamid G, Amara IEA, Anwar-Mohamed A, El-Kadi AOS. Modulation of cytochrome P450 1 (Cyp1) by vanadium in hepatic tissue and isolated hepatocyte of C57BL/6 mice. Arch Toxicol 2013; 87:1531-43. [DOI: 10.1007/s00204-013-1023-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2012] [Accepted: 02/06/2013] [Indexed: 10/27/2022]
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Amara IE, Anwar-Mohamed A, Abdelhamid G, El-Kadi AO. Mercury modulates the cytochrome P450 1a1, 1a2 and 1b1 in C57BL/6J mice: in vivo and in vitro studies. Toxicol Appl Pharmacol 2013; 266:419-29. [DOI: 10.1016/j.taap.2012.11.027] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2012] [Revised: 11/17/2012] [Accepted: 11/30/2012] [Indexed: 10/27/2022]
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Veselova I, Malinina L, Rodionov P, Shekhovtsova T. Properties and analytical applications of the self-assembled complex {peroxidase–chitosan}. Talanta 2012. [DOI: 10.1016/j.talanta.2012.07.028] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Montalbetti N, Leal Denis MF, Pignataro OP, Kobatake E, Lazarowski ER, Schwarzbaum PJ. Homeostasis of extracellular ATP in human erythrocytes. J Biol Chem 2011; 286:38397-38407. [PMID: 21921036 DOI: 10.1074/jbc.m111.221713] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
We explored the intra- and extracellular processes governing the kinetics of extracellular ATP (ATPe) in human erythrocytes stimulated with agents that increase cAMP. Using the luciferin-luciferase reaction in off-line luminometry we found both direct adenylyl cyclase activation by forskolin and indirect activation through β-adrenergic stimulation with isoproterenol-enhanced [ATP]e in a concentration-dependent manner. A mixture (3V) containing a combination of these agents and the phosphodiesterase inhibitor papaverine activated ATP release, leading to a 3-fold increase in [ATP]e, and caused increases in cAMP concentration (3-fold for forskolin + papaverine, and 10-fold for 3V). The pannexin 1 inhibitor carbenoxolone and a pannexin 1 blocking peptide ((10)Panx1) decreased [ATP]e by 75-84%. The residual efflux of ATP resulted from unavoidable mechanical perturbations stimulating a novel, carbenoxolone-insensitive pathway. In real-time luminometry experiments using soluble luciferase, addition of 3V led to an acute increase in [ATP]e to a constant value of ∼1 pmol × (10(6) cells)(-1). A similar treatment using a surface attached luciferase (proA-luc) triggered a rapid accumulation of surface ATP levels to a peak concentration of 2.4 pmol × (10(6) cells)(-1), followed by a slower exponential decay (t(½) = 3.7 min) to a constant value of 1.3 pmol × (10(6) cells)(-1). Both for soluble luciferase and proA-luc, ATP efflux was fully blocked by carbenoxolone, pointing to a 3V-induced mechanism of ATP release mediated by pannexin 1. Ecto-ATPase activity was extremely low (∼28 fmol × (10(6) cells min)(-1)), but nevertheless physiologically relevant considering the high density of erythrocytes in human blood.
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Affiliation(s)
- Nicolas Montalbetti
- IQUIFIB, Department of Biological Chemistry, School of Pharmacy and Biochemistry, University of Buenos Aires, Buenos Aires, CIII3AAD, Argentina
| | - Maria F Leal Denis
- IQUIFIB, Department of Biological Chemistry, School of Pharmacy and Biochemistry, University of Buenos Aires, Buenos Aires, CIII3AAD, Argentina
| | - Omar P Pignataro
- Laboratory of Molecular Endocrinology and Signal Transduction, Institute of Biology and Experimental Medicine-CONICET, Vuelta de Obligado 2490, CP 1428 Buenos Aires, Argentina; Department of Biological Chemistry, School of Sciences, University of Buenos Aires, Buenos Aires, CIII3AAD, Argentina
| | - Eiry Kobatake
- Department of Biological Information, Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8501, Japan
| | - Eduardo R Lazarowski
- Cystic Fibrosis/Pulmonary Research and Treatment Center, University of North Carolina, Chapel Hill, North Carolina 27599-7248
| | - Pablo J Schwarzbaum
- IQUIFIB, Department of Biological Chemistry, School of Pharmacy and Biochemistry, University of Buenos Aires, Buenos Aires, CIII3AAD, Argentina.
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FAN C, HU X, LI G, ZHU J, ZHU D. Adsorptive Behavior of Hemoglobin at a Platinum Electrode and Its Application to the Determination o f Protein. ANAL SCI 2000. [DOI: 10.2116/analsci.16.463] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Chunhai FAN
- Department of Biochemistry and National Key Laboratory of Pharmaceutical Biotechnology, Nanjing University
| | - Xiaofang HU
- Department of Biochemistry and National Key Laboratory of Pharmaceutical Biotechnology, Nanjing University
| | - Genxi LI
- Department of Biochemistry and National Key Laboratory of Pharmaceutical Biotechnology, Nanjing University
| | | | - Dexu ZHU
- Department of Biochemistry and National Key Laboratory of Pharmaceutical Biotechnology, Nanjing University
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Takahata K, Igarashi S. Spectrophotometric determination of trace amounts of hemoglobin using the oxidative decomposition reaction of a copper(II)-phthalocyanine complex. Clin Chim Acta 1999; 283:129-38. [PMID: 10404737 DOI: 10.1016/s0009-8981(99)00038-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
A catalytic effect of hemoglobin was found in the oxidative decomposition of a copper(II)-phthalocyanine complex (Cu-pts) with peroxomonosulfate. Based on this finding, a simple, rapid, highly sensitive and high-precision spectrophotometric method for hemoglobin was developed. In this indicator system, Cu-pts as the indicator and hemoglobin as the catalyst were simultaneously decomposed with peroxomonosulfate. Therefore, the slopes of the absorbance-time curve of the sample solution become equal to that of the blank solution after 5 min. The calibration curve was linear over the range of 12-258 microg/l. Detection limits (3sigma) were 8.13 microg/l, and the relative standard deviation was 2.05% (10 determinations) for 130 microg/l of hemoglobin. The metal ions did not significantly produce an interference in this method. The albumin had some influence but was permissible up to 6 times the weight of hemoglobin. The proposed method was applied to human blood samples with satisfactory results.
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Affiliation(s)
- K Takahata
- Department of Materials Science, Faculty of Engineering, Ibaraki University, Nakanarusawa, Hitachi, Japan
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Li G, Long Y, Chen H, Zhu D. Determination of traces of hemoglobin by square wave stripping voltammetry at a silver microelectrode. ACTA ACUST UNITED AC 1996; 356:359-60. [PMID: 15048343 DOI: 10.1007/s0021663560359] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/1995] [Revised: 04/19/1996] [Accepted: 04/28/1996] [Indexed: 10/26/2022]
Abstract
An electrochemical method was developed for the determination of traces of hemoglobin (Hb) by adsorption square wave voltammetric stripping at a bare silver microelectrode. Under optimum conditions the proposed method provided a linear response over the hemoglobin concentration range 5 to 100 nmol/L. The detection limit was 3 nmol/L. The relative standard deviation was 4.5% for 6 successive determinations at 50 nmol/L Hb. Other chemicals present in the sample did not interfere.
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Affiliation(s)
- G Li
- Department of Biochemistry and National Laboratory of Pharmaceutical Biotechnology, Nanjing University, 210093, Nanjing, P. R. China
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Pérez-Gilabert M, Sánchez-Ferrer A, García-Carmona F. Lipoxygenase-catalyzed oxidation of chlorpromazine by hydrogen peroxide at acidic pH. BIOCHIMICA ET BIOPHYSICA ACTA 1994; 1214:203-8. [PMID: 7918601 DOI: 10.1016/0005-2760(94)90045-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The hydroperoxidase activity of soybean lipoxygenase, a non-heme protein, oxidizes chlorpromazine using H2O2 at acidic pHs ranging from 3.0 to 4.0. The enzyme is assayed at pH 3.5, at which the half-life is 2 h (lower pHs cause higher inactivation rates). This oxidation is enzymatical since boiled enzyme or even iron ions both with H2O2 failed to produce any increase in absorbance. In addition, the concentration of CPZ radical cation formed and the concomitant enzyme activity directly depends on the enzyme concentration up to 0.23 microM. The Vmax value is 125 mumol/min per mg protein and the Km for chlorpromazine and H2O2 are 2.1 mM and 0.25 mM, respectively. Similar results were obtained when linoleic acid hydroperoxide was used instead of H2O2 with a Km value of 95 microM. The radical cation obtained in the oxidation of chlorpromazine by lipoxygenase decays by a disproportionation reaction. This permits to consider the overall reaction as a sum of an enzymatic reaction coupled with a chemical second order reaction with substrate regeneration, similar to those produced by peroxidases from different sources.
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Affiliation(s)
- M Pérez-Gilabert
- Departamento de Bioquímica y Biología Molecular, Facultad de Biología, Universidad de Murcia, Spain
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Pérez-Gilabert M, Sánchez-Ferrer A, García-Carmona F. Enzymatic oxidation of phenothiazines by lipoxygenase/H2O2 system. Biochem Pharmacol 1994; 47:2227-32. [PMID: 8031316 DOI: 10.1016/0006-2952(94)90260-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Lipoxygenase (LOX) (EC 1.13.11.12) oxidized a wide range of phenothiazine (Pt) tranquillizers to their corresponding radical cations in the presence of H2O2 by means of an enzymatic chemical second-order mechanism with substrate regeneration similar to that of horseradish peroxidase. The optimum pH of LOX for this hydroperoxidase activity was in the acid range (pH 3.0-4.0), as has been shown for other Pt oxidizing systems, such as peroxidase/H2O2 and haemoglobin. LOX showed Michaelis constants for Pt ranging from 1.4 to 8.5 mM and which, in some cases, e.g. trifluoperazine, displayed substrate inhibition. By contrast, it had a high affinity for H2O2 in the microM to mM range. A new, previously undescribed plot, which relates the enzymatic affinity and the apparent second-order decay of the cation radical, was developed to study the influence of the 2- and 10-substituents in the Pt ring. The implications of this new plot and the LOX-mediated Pt oxidation are also discussed.
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Affiliation(s)
- M Pérez-Gilabert
- Departmento de Bioquímica y Biología Molecular-A, Facultad de Biología, Universidad de Murcia, Spain
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