1
|
Port-Lougarre Y, Gourlaouen C, Vileno B, Giménez-Arnau E. Antioxidant Activity and Skin Sensitization of Eugenol and Isoeugenol: Two Sides of the Same Coin? Chem Res Toxicol 2023; 36:1804-1813. [PMID: 37922503 DOI: 10.1021/acs.chemrestox.3c00263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2023]
Abstract
Eugenol and isoeugenol are well acknowledged to possess antioxidant and thus cytoprotective activities. Yet both compounds are also important skin sensitizers, compelling the cosmetics and fragrance industries to notify their presence in manufactured products. While they are structurally very similar, they show significant differences in their sensitization properties. Consequently, eugenol and isoeugenol have been the subject of many mechanistic studies where the final oxidation forms, electrophilic ortho-quinone and quinone methide, are blamed as the reactive species forming an antigenic complex with nucleophilic residues of skin proteins, inducing skin sensitization. However, radical mechanisms could compete with such an electrophilic-nucleophilic pathway. The antioxidant activity results from neutralizing reactive oxygen radicals by the release of the phenolic hydrogen atom. The so-formed phenoxyl radicals can then fully delocalize upon the structure, becoming potentially reactive toward skin proteins at several positions. To obtain in-depth insights into such reactivity, we investigated in situ the formation of radicals from eugenol and isoeugenol using electron paramagnetic resonance combined with spin trapping in reconstructed human epidermis (RHE), mimicking human skin and closer to what may happen in vivo. Two modes of radical initiation were used, exposing RHE to (i) horseradish peroxidase (HRP), complementing RHE metabolic capacities, and mimicking peroxidases present in vivo or (ii) solar light using a AM 1.5 solar simulator. In both experimental approaches, where the antioxidant character of both compounds is revealed, oxygen- and carbon-centered radicals were formed in RHE. Our hypothesis is that such carbon radicals are relevant candidates to form antigenic entities prior to conversion into electrophilic quinones. On this basis, these studies suggest that pro- or prehapten fingerprints could be advanced depending on the radical initiation method. The introduction of HRP suggested that eugenol and isoeugenol behave as prohaptens, while when exposed to light, a prehapten nature could be highlighted.
Collapse
Affiliation(s)
- Yannick Port-Lougarre
- Institut de Chimie, UMR 7177, CNRS, Université de Strasbourg, 4 Rue Blaise Pascal, 67000 Strasbourg, France
| | - Christophe Gourlaouen
- Institut de Chimie, UMR 7177, CNRS, Université de Strasbourg, 4 Rue Blaise Pascal, 67000 Strasbourg, France
| | - Bertrand Vileno
- Institut de Chimie, UMR 7177, CNRS, Université de Strasbourg, 4 Rue Blaise Pascal, 67000 Strasbourg, France
| | - Elena Giménez-Arnau
- Institut de Chimie, UMR 7177, CNRS, Université de Strasbourg, 4 Rue Blaise Pascal, 67000 Strasbourg, France
| |
Collapse
|
2
|
da Cunha AS, dos S. Vianna Jr. A, Laurenti E. Modeling and simulation of the enzymatic degradation of 2,4,6-trichlorophenol using soybean peroxidase. BRAZILIAN JOURNAL OF CHEMICAL ENGINEERING 2021. [DOI: 10.1007/s43153-021-00135-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
|
3
|
Trujillo RM, Barraza DE, Zamora ML, Cattani-Scholz A, Madrid RE. Nanostructures in Hydrogen Peroxide Sensing. SENSORS 2021; 21:s21062204. [PMID: 33801140 PMCID: PMC8004286 DOI: 10.3390/s21062204] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 03/15/2021] [Accepted: 03/16/2021] [Indexed: 01/31/2023]
Abstract
In recent years, several devices have been developed for the direct measurement of hydrogen peroxide (H2O2), a key compound in biological processes and an important chemical reagent in industrial applications. Classical enzymatic biosensors for H2O2 have been recently outclassed by electrochemical sensors that take advantage of material properties in the nano range. Electrodes with metal nanoparticles (NPs) such as Pt, Au, Pd and Ag have been widely used, often in combination with organic and inorganic molecules to improve the sensing capabilities. In this review, we present an overview of nanomaterials, molecules, polymers, and transduction methods used in the optimization of electrochemical sensors for H2O2 sensing. The different devices are compared on the basis of the sensitivity values, the limit of detection (LOD) and the linear range of application reported in the literature. The review aims to provide an overview of the advantages associated with different nanostructures to assess which one best suits a target application.
Collapse
Affiliation(s)
- Ricardo Matias Trujillo
- Laboratorio de Medios e Interfases (LAMEIN), DBI, FACET, Universidad Nacional de Tucumán, Av. Independencia 1800, 4000 Tucumán, Argentina; (R.M.T.); (D.E.B.); (M.L.Z.)
- Instituto Superior de Investigaciones Biológicas (INSIBIO), CONICET, Chacabuco 461, 4000 Tucumán, Argentina
| | - Daniela Estefanía Barraza
- Laboratorio de Medios e Interfases (LAMEIN), DBI, FACET, Universidad Nacional de Tucumán, Av. Independencia 1800, 4000 Tucumán, Argentina; (R.M.T.); (D.E.B.); (M.L.Z.)
- Instituto Superior de Investigaciones Biológicas (INSIBIO), CONICET, Chacabuco 461, 4000 Tucumán, Argentina
| | - Martin Lucas Zamora
- Laboratorio de Medios e Interfases (LAMEIN), DBI, FACET, Universidad Nacional de Tucumán, Av. Independencia 1800, 4000 Tucumán, Argentina; (R.M.T.); (D.E.B.); (M.L.Z.)
- Instituto Superior de Investigaciones Biológicas (INSIBIO), CONICET, Chacabuco 461, 4000 Tucumán, Argentina
| | - Anna Cattani-Scholz
- Walter Schottky Institute and Physics Department, Technical University of Munich, Am Coulombwall 4, 85748 Garching, Germany
- Correspondence: (A.C.-S.); (R.E.M.)
| | - Rossana Elena Madrid
- Laboratorio de Medios e Interfases (LAMEIN), DBI, FACET, Universidad Nacional de Tucumán, Av. Independencia 1800, 4000 Tucumán, Argentina; (R.M.T.); (D.E.B.); (M.L.Z.)
- Instituto Superior de Investigaciones Biológicas (INSIBIO), CONICET, Chacabuco 461, 4000 Tucumán, Argentina
- Correspondence: (A.C.-S.); (R.E.M.)
| |
Collapse
|
4
|
Ingenbosch KN, Quint S, Dyllick‐Brenzinger M, Wunschik DS, Kiebist J, Süss P, Liebelt U, Zuhse R, Menyes U, Scheibner K, Mayer C, Opwis K, Gutmann JS, Hoffmann‐Jacobsen K. Singlet-Oxygen Generation by Peroxidases and Peroxygenases for Chemoenzymatic Synthesis. Chembiochem 2021; 22:398-407. [PMID: 32798264 PMCID: PMC7891382 DOI: 10.1002/cbic.202000326] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 08/13/2020] [Indexed: 11/23/2022]
Abstract
Singlet oxygen is a reactive oxygen species undesired in living cells but a rare and valuable reagent in chemical synthesis. We present a fluorescence spectroscopic analysis of the singlet-oxygen formation activity of commercial peroxidases and novel peroxygenases. Singlet-oxygen sensor green (SOSG) is used as fluorogenic singlet oxygen trap. Establishing a kinetic model for the reaction cascade to the fluorescent SOSG endoperoxide permits a kinetic analysis of enzymatic singlet-oxygen formation. All peroxidases and peroxygenases show singlet-oxygen formation. No singlet oxygen activity could be found for any catalase under investigation. Substrate inhibition is observed for all reactive enzymes. The commercial dye-decolorizing peroxidase industrially used for dairy bleaching shows the highest singlet-oxygen activity and the lowest inhibition. This enzyme was immobilized on a textile carrier and successfully applied for a chemical synthesis. Here, ascaridole was synthesized via enzymatically produced singlet oxygen.
Collapse
Affiliation(s)
- Kim N. Ingenbosch
- Niederrhein University of Applied SciencesDepartment of Chemistry and Institute for Coatings and Surface ChemistryAdlerstrasse 3247798KrefeldGermany
- Deutsches Textilforschungszentrum Nord-West gGmbHAdlerstrasse 147798KrefeldGermany
- Institute of Physical Chemistry and CENIDE (Center for Nanointegration)University Duisburg–EssenUniversitätsstraße 545117EssenGermany
| | - Stephan Quint
- Chiracon GmbHIm Biotechnologiepark 914943LuckenwaldeGermany
| | | | - Dennis S. Wunschik
- Niederrhein University of Applied SciencesDepartment of Chemistry and Institute for Coatings and Surface ChemistryAdlerstrasse 3247798KrefeldGermany
- Deutsches Textilforschungszentrum Nord-West gGmbHAdlerstrasse 147798KrefeldGermany
- Institute of Physical Chemistry and CENIDE (Center for Nanointegration)University Duisburg–EssenUniversitätsstraße 545117EssenGermany
| | - Jan Kiebist
- Faculty of Environmental and Natural SciencesBrandenburg University of Technology Cottbus-SenftenbergGroßenhainer Strasse 5701968SenftenbergGermany
| | - Philipp Süss
- Enzymicals AGWalther-Rathenau-Str. 49a17489GreifswaldGermany
| | - Ute Liebelt
- Enzymicals AGWalther-Rathenau-Str. 49a17489GreifswaldGermany
- Present address: Leibniz Institute for Plasma Science and TechnologyFelix-Hausdorff-Strasse 217489GreifswaldGermany
| | - Ralf Zuhse
- Chiracon GmbHIm Biotechnologiepark 914943LuckenwaldeGermany
| | - Ulf Menyes
- Enzymicals AGWalther-Rathenau-Str. 49a17489GreifswaldGermany
| | - Katrin Scheibner
- Faculty of Environmental and Natural SciencesBrandenburg University of Technology Cottbus-SenftenbergGroßenhainer Strasse 5701968SenftenbergGermany
| | - Christian Mayer
- Institute of Physical Chemistry and CENIDE (Center for Nanointegration)University Duisburg–EssenUniversitätsstraße 545117EssenGermany
| | - Klaus Opwis
- Deutsches Textilforschungszentrum Nord-West gGmbHAdlerstrasse 147798KrefeldGermany
| | - Jochen S. Gutmann
- Deutsches Textilforschungszentrum Nord-West gGmbHAdlerstrasse 147798KrefeldGermany
- Institute of Physical Chemistry and CENIDE (Center for Nanointegration)University Duisburg–EssenUniversitätsstraße 545117EssenGermany
| | - Kerstin Hoffmann‐Jacobsen
- Niederrhein University of Applied SciencesDepartment of Chemistry and Institute for Coatings and Surface ChemistryAdlerstrasse 3247798KrefeldGermany
| |
Collapse
|
5
|
Sato S, Nakamura H. Labeling of Peroxide-Induced Oxidative Stress Hotspots by Hemin-Catalyzed Tyrosine Click. Chem Pharm Bull (Tokyo) 2020; 68:885-890. [PMID: 32879229 DOI: 10.1248/cpb.c20-00434] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Tyrosyl radical generation is one of the major factors for hemin/peroxide-induced oxidative stress. A method for trapping tyrosyl radical directly was developed using N-methyl luminol derivative, a tyrosine labeling reagent. N-Methyl luminol derivative selectively forms a covalent bond with a tyrosine residue under the single-electron oxidation condition. This reaction labels oxidative stress hotspots not only at the protein level but also at the level of tyrosine residues undergoing oxidation. Human serum albumin complexed with hemin was labeled at Tyr138, the tyrosine residue closest to the hemin binding site and most strongly subjected to oxidative stress caused by hemin/H2O2. Oxidatively damaged proteins were visualized in protein mixtures.
Collapse
Affiliation(s)
- Shinichi Sato
- Frontier Research Institute for Interdisciplinary Sciences, Tohoku University.,Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology
| | - Hiroyuki Nakamura
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology
| |
Collapse
|
6
|
Enzymatic Degradation of 2,4,6-Trichlorophenol in a Microreactor using Soybean Peroxidase. Symmetry (Basel) 2020. [DOI: 10.3390/sym12071129] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Soybean peroxidase is an enzyme extracted from soybean seed hulls. In the presence of hydrogen peroxide, the enzyme has the potential to catalyze the biodegradation of toxic substances like chlorophenols. For this reason, its use in wastewater treatment processes is environmentally friendly since the enzyme can be obtained from a renewable and abundant raw material. In this work, enzymatic biodegradation of 2,4,6-trichlorophenol performed by soybean peroxidase in a microreactor was studied experimentally and theoretically. The experimental data set was obtained with a volume of 250 μL by using different soybean peroxidase concentrations and different reaction times. The fluid dynamics of the microreactor was modeled as well, using ANSYS CFX. The simulations exhibited secondary flows, which enhanced mixing. Although the laminar flow was developed, it can be assumed to be a well-mixed medium. The kinetic data were evaluated through a mechanistic model, the modified bi-bi ping-pong model, which is adequate to represent the enzymatic degradation using peroxidases. The model was composed of an initial value problem for ordinary differential equations that were solved using MATLAB. Some kinetic constants were estimated using the least square function. The results of the model fit well the experimental data.
Collapse
|
7
|
Gkaniatsou E, Serre C, Mahy JP, Steunou N, Ricoux R, Sicard C. Enhancing microperoxidase activity and selectivity: immobilization in metal-organic frameworks. J PORPHYR PHTHALOCYA 2019. [DOI: 10.1142/s1088424619300106] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Microperoxidases 8 (MP8) and 11 (MP11) are heme-containing peptides obtained by the proteolytic digestion of Cytochrome c. They act as mini-enzymes that combine both peroxidase-like and Cytochrome P450-like activities that may be useful in the synthesis of fine chemicals or in the degradation of environmental pollutants. However, their use is limited by their instability in solution due to (i) the bleaching of the heme in the presence of an excess of H2O2, (ii) the decoordination of the distal histidine ligand of the iron under acidic conditions and, (iii) their tendency to aggregate in aqueous alkaline solutions, even at low concentrations. Additionally, both MP8 and MP11 show relatively low selectivity, due to the lack of control of the substrates by a specific catalytic pocket on the distal face of the heme. Both stability and selectivity issues can be effectively addressed by immobilization of microperoxidases in solid matrices, which can also lead to their possible recycling from the reaction medium. Considering their relatively small size, the pore inclusion of MPs into Metal-Organic Frameworks appeared to be more adequate compared to other immobilization methods that have been widely investigated for decades. The present minireview describes the catalytic activities of MP8 and MP11, their limitations, and various results describing their immobilization into MOFs which led to MP11- or MP8@MOF hybrid materials that display good activity in the oxidation of dyes and phenol derivatives, with remarkable recyclability due to the stabilization of the MPs inside the MOF cavities. An example of selective oxidation of dyes according to their charge by MP8@MOF hybrid materials is also highlighted.
Collapse
Affiliation(s)
- Effrosyni Gkaniatsou
- Institut Lavoisier de Versailles, UVSQ, CNRS, Université Paris-Saclay, 45 Avenue des Etat-Unis, Versailles, France
| | - Christian Serre
- Institut des Matériaux Poreux de Paris, UMR-8004 CNRS-ENS-ESPCI, PSL Research University, 75005, Paris, France
| | - Jean-Pierre Mahy
- Laboratoire de Chimie Bioorganique et Bioinorganique, Institut de Chimie Moléculaire et des Matériaux d’Orsay, UMR 8182, Université Paris Sud, Université Paris-Saclay, 91405 Orsay Cedex, France
| | - Nathalie Steunou
- Institut Lavoisier de Versailles, UVSQ, CNRS, Université Paris-Saclay, 45 Avenue des Etat-Unis, Versailles, France
| | - Rémy Ricoux
- Laboratoire de Chimie Bioorganique et Bioinorganique, Institut de Chimie Moléculaire et des Matériaux d’Orsay, UMR 8182, Université Paris Sud, Université Paris-Saclay, 91405 Orsay Cedex, France
| | - Clémence Sicard
- Institut Lavoisier de Versailles, UVSQ, CNRS, Université Paris-Saclay, 45 Avenue des Etat-Unis, Versailles, France
| |
Collapse
|
8
|
Benson KR, Gorecki J, Nikiforov A, Tsui W, Kasi RM, Kumar CV. Cytochrome c–poly(acrylic acid) conjugates with improved peroxidase turnover number. Org Biomol Chem 2019; 17:4043-4048. [DOI: 10.1039/c9ob00541b] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Cytochrome c–poly(acrylic acid) conjugates with 34-fold enhanced peroxidase activity due to acidification of enzyme microenvironment and suppression of wasteful intermediates.
Collapse
Affiliation(s)
- K. R. Benson
- Department of Chemistry
- University of Connecticut
- Storrs
- USA
| | - J. Gorecki
- Department of Chemistry
- University of Connecticut
- Storrs
- USA
| | - A. Nikiforov
- Department of Chemistry
- University of Connecticut
- Storrs
- USA
| | - W. Tsui
- Department of Chemistry
- University of Connecticut
- Storrs
- USA
| | - R. M. Kasi
- Department of Chemistry
- University of Connecticut
- Storrs
- USA
- Institute of Materials Science
| | - C. V. Kumar
- Department of Chemistry
- University of Connecticut
- Storrs
- USA
- Institute of Materials Science
| |
Collapse
|
9
|
Samuni U, Maimon E, Goldstein S. A kinetic study of the oxidation of hydroxamic acids by compounds I and II of horseradish peroxidase: Effect of transition metal ions. J COORD CHEM 2018. [DOI: 10.1080/00958972.2018.1493200] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Affiliation(s)
- Uri Samuni
- Chemistry & Biochemistry Department, Queens College, City University of New York, Flushing, NY, USA
- Ph.D. Programs in Biochemistry and Chemistry, The Graduate Center of the City University of New York, New York, NY, USA
| | - Eric Maimon
- Nuclear Research Centre Negev, Beer Sheva, Israel
| | - Sara Goldstein
- Institute of Chemistry, The Accelerator Laboratory, the Hebrew University of Jerusalem, Jerusalem, Israel
| |
Collapse
|
10
|
Maimon E, Samuni A, Goldstein S. Nitrogen Dioxide Reaction with Nitroxide Radical Derived from Hydroxamic Acids: The Intermediacy of Acyl Nitroso and Nitroxyl (HNO). J Phys Chem A 2018; 122:3747-3753. [PMID: 29608853 DOI: 10.1021/acs.jpca.8b02300] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Hydroxamic acids (RC(O)NHOH) form a class of compounds that display interesting chemical and biological properties The chemistry of RC(O)NHOH) is associated with one- and two-electron oxidations forming the respective nitroxide radical (RC(O)NHO•) and acyl nitroso (RC(O)N═O), respectively, which are relatively unstable species. In the present study, the kinetics and mechanism of the •NO2 reaction with nitroxide radicals derived from acetohydroxamic acid, suberohydroxamic acid, benzohydroxamic acid, and suberoylanilide hydroxamic acid have been studied in alkaline solutions. Ionizing radiation was used to generate about equal yields of these radicals, demonstrating that the oxidation of the transient nitroxide radical by •NO2 produces HNO and nitrite at about equal yields. The rate constant of •NO2 reaction with the nitroxide radical derived from acetohydroxamic acid has been determined to be (2.5 ± 0.5) × 109 M-1 s-1. This reaction forms a transient intermediate absorbing at 314 nm, which decays via a first-order reaction whose rate increases upon increasing the pH or the hydroxamic acid concentration. Transient intermediates absorbing around 314 nm are also formed during the oxidation of hydroxamic acids by H2O2 catalyzed by horseradish peroxidase. It is shown that HNO is formed during the decomposition of these intermediates, and therefore, they are assigned to acyl nitroso compounds. This study provides for the first time a direct spectrophotometric detection of acyl nitroso compounds in aqueous solutions allowing the study of their chemistry and reaction kinetics.
Collapse
Affiliation(s)
- Eric Maimon
- Nuclear Research Centre Negev , Beer Sheva , Israel
| | - Amram Samuni
- Institute of Medical Research Israel-Canada , Medical School, The Hebrew University of Jerusalem , Jerusalem 91120 , Israel
| | - Sara Goldstein
- Institute of Chemistry, The Accelerator Laboratory , The Hebrew University of Jerusalem , Jerusalem 91904 , Israel
| |
Collapse
|
11
|
Samuni A, Maimon E, Goldstein S. Mechanism of HRP-catalyzed nitrite oxidation by H 2O 2 revisited: Effect of nitroxides on enzyme inactivation and its catalytic activity. Free Radic Biol Med 2017; 108:832-839. [PMID: 28495446 DOI: 10.1016/j.freeradbiomed.2017.05.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Revised: 05/01/2017] [Accepted: 05/07/2017] [Indexed: 10/19/2022]
Abstract
The peroxidative activity of horseradish peroxidase (HRP) undergoes progressive inactivation while catalyzing the oxidation of nitrite by H2O2. The extent of inactivation increases as the pH increases, [nitrite] decreases or [H2O2] increases, and is accompanied by a loss of the Soret peak of HRP along with yellow-greenish coloration of the solution. HRP-catalyzed nitrite oxidation by H2O2 involves not only the formation of compounds I and II as transient heme species, but also compound III, all of which in turn, oxidize nitrite yielding •NO2. The rate constant of nitrite oxidation by compound III is at least 10-fold higher than that by compound II, which is also reducible by •NO2 where its reduction by nitrite is the rate-determining step of the catalytic cycle. The extent of the loss of the Soret peak of HRP is lower than the loss of its peroxidative activity implying that deterioration of the heme moiety leading to iron release only partially contributes toward heme inactivation. Cyclic stable nitroxide radicals, such as 2,2,6,6-tetramethyl-piperidine-N-oxyl (TPO), 4-OH-TPO and 4-NH2-TPO at µM concentrations detoxify •NO2 thus protecting HRP against inactivation mediated by this radical. Hence, HRP inactivation proceeds via nitration of the porphyrin ring most probably through compound I reaction with •NO2, which partially leads to deterioration of the heme moiety. The nitroxide acts catalytically since its oxidation by •NO2 yields the respective oxoammonium cation, which is readily reduced back to the nitroxide by H2O2, superoxide ion radical, and nitrite. In addition, the nitroxide catalytically inhibits tyrosine nitration mediated by HRP/H2O2/nitrite reactions system as it efficiently competes with tyrosyl radical for •NO2. The inhibition by nitroxides of tyrosine nitration is demonstrated also in the case of microperoxidase (MP-11) and cytochrome c revealing an additional role played by nitroxide antioxidants.
Collapse
Affiliation(s)
- Amram Samuni
- Institute of Medical Research Israel-Canada, Medical School, The Hebrew University of Jerusalem, Jerusalem 91120, Israel
| | - Eric Maimon
- Nuclear Research Centre Negev, Be'er Sheva, Israel
| | - Sara Goldstein
- Institute of Chemistry, The Accelerator Laboratory, the Hebrew University of Jerusalem, Jerusalem 91904, Israel.
| |
Collapse
|
12
|
Samuni A, Maimon E, Goldstein S. Nitroxides protect horseradish peroxidase from H 2O 2-induced inactivation and modulate its catalase-like activity. Biochim Biophys Acta Gen Subj 2017; 1861:2060-2069. [PMID: 28365302 DOI: 10.1016/j.bbagen.2017.03.021] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Revised: 03/05/2017] [Accepted: 03/20/2017] [Indexed: 11/24/2022]
Abstract
BACKGROUND Horseradish peroxidase (HRP) catalyzes H2O2 dismutation while undergoing heme inactivation. The mechanism underlying this process has not been fully elucidated. The effects of nitroxides, which protect metmyoglobin and methemoglobin against H2O2-induced inactivation, have been investigated. METHODS HRP reaction with H2O2 was studied by following H2O2 depletion, O2 evolution and heme spectral changes. Nitroxide concentration was followed by EPR spectroscopy, and its reactions with the oxidized heme species were studied using stopped-flow. RESULTS Nitroxide protects HRP against H2O2-induced inactivation. The rate of H2O2 dismutation in the presence of nitroxide obeys zero-order kinetics and increases as [nitroxide] increases. Nitroxide acts catalytically since its oxidized form is readily reduced to the nitroxide mainly by H2O2. The nitroxide efficacy follows the order 2,2,6,6-tetramethyl-piperidine-N-oxyl (TPO)>4-OH-TPO>3-carbamoyl proxyl>4-oxo-TPO, which correlates with the order of the rate constants of nitroxide reactions with compounds I, II, and III. CONCLUSIONS Nitroxide catalytically protects HRP against inactivation induced by H2O2 while modulating its catalase-like activity. The protective role of nitroxide at μM concentrations is attributed to its efficient oxidation by P940, which is the precursor of the inactivated form P670. Modeling the dismutation kinetics in the presence of nitroxide adequately fits the experimental data. In the absence of nitroxide the simulation fits the observed kinetics only if it does not include the formation of a Michaelis-Menten complex. GENERAL SIGNIFICANCE Nitroxides catalytically protect heme proteins against inactivation induced by H2O2 revealing an additional role played by nitroxide antioxidants in vivo.
Collapse
Affiliation(s)
- Amram Samuni
- Institute of Medical Research Israel-Canada, Medical School, The Hebrew University of Jerusalem, Jerusalem 91120, Israel
| | - Eric Maimon
- Nuclear Research Centre Negev, Beer Sheva, Israel
| | - Sara Goldstein
- Institute of Chemistry, The Accelerator Laboratory, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.
| |
Collapse
|
13
|
Qu R, Shi H, Wang R, Cheng T, Ma R, An Y, Shi L. Hemin-micelles immobilized in alginate hydrogels as artificial enzymes with peroxidase-like activity and substrate selectivity. Biomater Sci 2017; 5:570-577. [DOI: 10.1039/c6bm00813e] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Hemin-micelles immobilized in hydrogels were designed, which function as efficient artificial enzymes with high catalytic activity and substrate selectivity.
Collapse
Affiliation(s)
- Rui Qu
- State Key Laboratory of Medicinal Chemical Biology
- Key Laboratory of Functional Polymer Materials
- Ministry of Education
- Institute of Polymer Chemistry
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin)
| | - Hejin Shi
- State Key Laboratory of Medicinal Chemical Biology
- Key Laboratory of Functional Polymer Materials
- Ministry of Education
- Institute of Polymer Chemistry
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin)
| | - Ruolin Wang
- State Key Laboratory of Medicinal Chemical Biology
- Key Laboratory of Functional Polymer Materials
- Ministry of Education
- Institute of Polymer Chemistry
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin)
| | - Tangjian Cheng
- State Key Laboratory of Medicinal Chemical Biology
- Key Laboratory of Functional Polymer Materials
- Ministry of Education
- Institute of Polymer Chemistry
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin)
| | - Rujiang Ma
- State Key Laboratory of Medicinal Chemical Biology
- Key Laboratory of Functional Polymer Materials
- Ministry of Education
- Institute of Polymer Chemistry
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin)
| | - Yingli An
- State Key Laboratory of Medicinal Chemical Biology
- Key Laboratory of Functional Polymer Materials
- Ministry of Education
- Institute of Polymer Chemistry
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin)
| | - Linqi Shi
- State Key Laboratory of Medicinal Chemical Biology
- Key Laboratory of Functional Polymer Materials
- Ministry of Education
- Institute of Polymer Chemistry
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin)
| |
Collapse
|
14
|
Qu R, Shen L, Qu A, Wang R, An Y, Shi L. Artificial Peroxidase/Oxidase Multiple Enzyme System Based on Supramolecular Hydrogel and Its Application as a Biocatalyst for Cascade Reactions. ACS APPLIED MATERIALS & INTERFACES 2015; 7:16694-16705. [PMID: 26173996 DOI: 10.1021/acsami.5b04398] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Inspired by delicate structures and multiple functions of natural multiple enzyme architectures such as peroxisomes, we constructed an artificial multiple enzyme system by coencapsulation of glucose oxidases (GOx) and artificial peroxidases in a supramolecular hydrogel. The artificial peroxidase was a functional complex micelle, which was prepared by the self-assembly of diblock copolymer and hemin. Compared with catalase or horseradish peroxidase (HRP), the functional micelle exhibited comparable activity and better stability, which provided more advantages in constructing a multienzyme with a proper oxidase. The hydrogel containing the two catalytic centers was further used as a catalyst for green oxidation of glucose, which was a typical cascade reaction. Glucose was oxidized by oxygen (O2) via the GOx-mediated reaction, producing toxic intermediate hydrogen peroxide (H2O2). The produced H2O2 further oxidized peroxidase substrates catalyzed by hemin-micelles. By regulating the diffusion modes of the enzymes and substrates, the artificial multienzyme based on hydrogel could successfully activate the cascade reaction, which the soluble enzyme mixture could not achieve. The hydrogel, just like a protective covering, protected oxidases and micelles from inactivation via toxic intermediates and environmental changes. The artificial multienzyme could efficiently achieve the oxidation task along with effectively eliminating the toxic intermediates. In this way, this system possesses great potentials for glucose detection and green oxidation of a series of substrates related to biological processes.
Collapse
Affiliation(s)
- Rui Qu
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Functional Polymer Materials, Ministry of Education, Institute of Polymer Chemistry, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Nankai University, Tianjin, 300071, China
| | - Liangliang Shen
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Functional Polymer Materials, Ministry of Education, Institute of Polymer Chemistry, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Nankai University, Tianjin, 300071, China
| | - Aoting Qu
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Functional Polymer Materials, Ministry of Education, Institute of Polymer Chemistry, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Nankai University, Tianjin, 300071, China
| | - Ruolin Wang
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Functional Polymer Materials, Ministry of Education, Institute of Polymer Chemistry, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Nankai University, Tianjin, 300071, China
| | - Yingli An
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Functional Polymer Materials, Ministry of Education, Institute of Polymer Chemistry, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Nankai University, Tianjin, 300071, China
| | - Linqi Shi
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Functional Polymer Materials, Ministry of Education, Institute of Polymer Chemistry, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Nankai University, Tianjin, 300071, China
| |
Collapse
|
15
|
Córdoba A, Alasino N, Asteasuain M, Magario I, Ferreira M. Mechanistic evaluation of hematin action as a horseradish peroxidase biomimetic on the 4-aminoantipyrine/phenol oxidation reaction. Chem Eng Sci 2015. [DOI: 10.1016/j.ces.2015.02.031] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
|
16
|
Thanh Mai Pham L, Eom MH, Kim YH. Inactivating effect of phenolic unit structures on the biodegradation of lignin by lignin peroxidase from Phanerochaete chrysosporium. Enzyme Microb Technol 2014; 61-62:48-54. [DOI: 10.1016/j.enzmictec.2014.04.013] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2014] [Revised: 04/22/2014] [Accepted: 04/22/2014] [Indexed: 11/24/2022]
|
17
|
Li J, Mei H, Zheng W, Pan P, Sun X, Li F, Guo F, Zhou H, Ma J, Xu X, Zheng Y. A novel hydrogen peroxide biosensor based on hemoglobin-collagen-CNTs composite nanofibers. Colloids Surf B Biointerfaces 2014; 118:77-82. [DOI: 10.1016/j.colsurfb.2014.03.035] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2013] [Revised: 03/13/2014] [Accepted: 03/20/2014] [Indexed: 10/25/2022]
|
18
|
Lopes GR, Pinto DCGA, Silva AMS. Horseradish peroxidase (HRP) as a tool in green chemistry. RSC Adv 2014. [DOI: 10.1039/c4ra06094f] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The horseradish peroxidase (HRP) potential in organic synthesis.
Collapse
Affiliation(s)
- Guido R. Lopes
- Department of Chemistry & QOPNA
- University of Aveiro
- 3810-193 Aveiro, Portugal
| | | | - Artur M. S. Silva
- Department of Chemistry & QOPNA
- University of Aveiro
- 3810-193 Aveiro, Portugal
| |
Collapse
|
19
|
Ueda T, Kitagishi H, Kano K. Intramolecular Direct Oxygen Transfer from Oxoferryl Porphyrin to a Sulfide Bond. Inorg Chem 2013; 53:543-51. [DOI: 10.1021/ic4026393] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Takunori Ueda
- Department of Molecular Chemistry and Biochemistry, Doshisha University, Kyotanabe, Kyoto 610-0321, Japan
| | - Hiroaki Kitagishi
- Department of Molecular Chemistry and Biochemistry, Doshisha University, Kyotanabe, Kyoto 610-0321, Japan
| | - Koji Kano
- Department of Molecular Chemistry and Biochemistry, Doshisha University, Kyotanabe, Kyoto 610-0321, Japan
| |
Collapse
|
20
|
Venanzi M, Cianfanelli S, Palleschi A. Mimicking hemoproteins: a new synthetic metalloenzyme based on a Fe(III)-mesoporphyrin functionalized by two helical decapeptides. J Pept Sci 2013; 20:36-45. [DOI: 10.1002/psc.2586] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2013] [Revised: 10/15/2013] [Accepted: 10/16/2013] [Indexed: 01/16/2023]
Affiliation(s)
- Mariano Venanzi
- Department of Chemical Sciences and Technologies; University of Rome Tor Vergata; Rome Italy
| | - Sabrina Cianfanelli
- Department of Chemical Sciences and Technologies; University of Rome Tor Vergata; Rome Italy
| | - Antonio Palleschi
- Department of Chemical Sciences and Technologies; University of Rome Tor Vergata; Rome Italy
| |
Collapse
|
21
|
Challier L, Miranda-Castro R, Marchal D, Noël V, Mavré F, Limoges B. Kinetic Rotating Droplet Electrochemistry: A Simple and Versatile Method for Reaction Progress Kinetic Analysis in Microliter Volumes. J Am Chem Soc 2013; 135:14215-28. [DOI: 10.1021/ja405415q] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Lylian Challier
- ITODYS, UMR 7086 CNRS, and ‡Laboratoire d’Electrochimie Moléculaire,
UMR 7591 CNRS, Université Paris Diderot, Sorbonne Paris Cité, 15 rue Jean-Antoine de Baïf, F-75205 Paris Cedex 13, France
| | - Rebeca Miranda-Castro
- ITODYS, UMR 7086 CNRS, and ‡Laboratoire d’Electrochimie Moléculaire,
UMR 7591 CNRS, Université Paris Diderot, Sorbonne Paris Cité, 15 rue Jean-Antoine de Baïf, F-75205 Paris Cedex 13, France
| | - Damien Marchal
- ITODYS, UMR 7086 CNRS, and ‡Laboratoire d’Electrochimie Moléculaire,
UMR 7591 CNRS, Université Paris Diderot, Sorbonne Paris Cité, 15 rue Jean-Antoine de Baïf, F-75205 Paris Cedex 13, France
| | - Vincent Noël
- ITODYS, UMR 7086 CNRS, and ‡Laboratoire d’Electrochimie Moléculaire,
UMR 7591 CNRS, Université Paris Diderot, Sorbonne Paris Cité, 15 rue Jean-Antoine de Baïf, F-75205 Paris Cedex 13, France
| | - François Mavré
- ITODYS, UMR 7086 CNRS, and ‡Laboratoire d’Electrochimie Moléculaire,
UMR 7591 CNRS, Université Paris Diderot, Sorbonne Paris Cité, 15 rue Jean-Antoine de Baïf, F-75205 Paris Cedex 13, France
| | - Benoît Limoges
- ITODYS, UMR 7086 CNRS, and ‡Laboratoire d’Electrochimie Moléculaire,
UMR 7591 CNRS, Université Paris Diderot, Sorbonne Paris Cité, 15 rue Jean-Antoine de Baïf, F-75205 Paris Cedex 13, France
| |
Collapse
|
22
|
Zhao X, Khajo A, Jarrett S, Suarez J, Levitsky Y, Burger RM, Jarzecki AA, Magliozzo RS. Specific function of the Met-Tyr-Trp adduct radical and residues Arg-418 and Asp-137 in the atypical catalase reaction of catalase-peroxidase KatG. J Biol Chem 2012; 287:37057-65. [PMID: 22918833 DOI: 10.1074/jbc.m112.401208] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Catalase activity of the dual-function heme enzyme catalase-peroxidase (KatG) depends on several structural elements, including a unique adduct formed from covalently linked side chains of three conserved amino acids (Met-255, Tyr-229, and Trp-107, Mycobacterium tuberculosis KatG numbering) (MYW). Mutagenesis, electron paramagnetic resonance, and optical stopped-flow experiments, along with calculations using density functional theory (DFT) methods revealed the basis of the requirement for a radical on the MYW-adduct, for oxyferrous heme, and for conserved residues Arg-418 and Asp-137 in the rapid catalase reaction. The participation of an oxyferrous heme intermediate (dioxyheme) throughout the pH range of catalase activity is suggested from our finding that carbon monoxide inhibits the activity at both acidic and alkaline pH. In the presence of H(2)O(2), the MYW-adduct radical is formed normally in KatG[D137S] but this mutant is defective in forming dioxyheme and lacks catalase activity. KatG[R418L] is also catalase deficient but exhibits normal formation of the adduct radical and dioxyheme. Both mutants exhibit a coincidence between MYW-adduct radical persistence and H(2)O(2) consumption as a function of time, and enhanced subunit oligomerization during turnover, suggesting that the two mutations disrupting catalase turnover allow increased migration of the MYW-adduct radical to protein surface residues. DFT calculations showed that an interaction between the side chain of residue Arg-418 and Tyr-229 in the MYW-adduct radical favors reaction of the radical with the adjacent dioxyheme intermediate present throughout turnover in WT KatG. Release of molecular oxygen and regeneration of resting enzyme are thereby catalyzed in the last step of a proposed catalase reaction.
Collapse
Affiliation(s)
- Xiangbo Zhao
- Department of Chemistry, Brooklyn College, Brooklyn, New York 11210, USA
| | | | | | | | | | | | | | | |
Collapse
|
23
|
Zamorano LS, Cuadrado NH, Galende PP, Roig MG, Shnyrov VL. Steady-state kinetics of <i>Roystonea regia</i> palm tree peroxidase. ACTA ACUST UNITED AC 2012. [DOI: 10.4236/jbpc.2012.31002] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
24
|
Cuadrado NH, Zhadan GG, Roig MG, Shnyrov VL. Suicide inactivation of peroxidase from Chamaerops excelsa palm tree leaves. Int J Biol Macromol 2011; 49:1078-82. [DOI: 10.1016/j.ijbiomac.2011.09.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2011] [Revised: 08/31/2011] [Accepted: 09/01/2011] [Indexed: 10/17/2022]
|
25
|
Yang X, Fang C, Mei H, Chang T, Cao Z, Shangguan D. Characterization of G-quadruplex/hemin peroxidase: substrate specificity and inactivation kinetics. Chemistry 2011; 17:14475-84. [PMID: 22106035 DOI: 10.1002/chem.201101941] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2011] [Indexed: 02/05/2023]
Abstract
Recently, G-quadruplex/hemin (G4/hemin) complexes have been found to exhibit peroxidase activity, and this feature has been extensively exploited for colorimetric detection of various targets. To further understand and characterize this important DNAzyme, its substrate specificity, inactivation mechanism, and kinetics have been examined by comparison with horseradish peroxidase (HRP). G4/hemin DNAzyme exhibits broader substrate specificity and much higher inactivation rate than HRP because of the exposure of the catalytic hemin center. The inactivation of G4/hemin DNAzyme is mainly attributed to the degradation of hemin by H(2)O(2) rather than the destruction of G4. Both the inactivation rate and catalytic oxidation rate of G4/hemin DNAzyme depend on the concentration of H(2)O(2), which suggests that active intermediates formed by G4/hemin and H(2)O(2) are the branch point of catalysis and inactivation. Reducing substrates greatly inhibit the inactivation of G4/hemin DNAzyme by rapidly reacting with the active intermediates. A possible catalytic and inactivation process of G4/hemin has been proposed. These results imply a potential cause for the hemin-mediated cellular injury and provide insightful information for the future application of G4/hemin DNAzyme.
Collapse
Affiliation(s)
- Xiaojuan Yang
- Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Zhongguancun, Beijing, 100190, PR China
| | | | | | | | | | | |
Collapse
|
26
|
Puiu M, Babaligea I, Olmazu C, Răducan A, Oancea D. Peroxidase-mediated oxidation of l-dopa: A kinetic approach. Biochem Eng J 2010. [DOI: 10.1016/j.bej.2010.08.017] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
|
27
|
Li Y, Zhang Q, Li J. Direct electrochemistry of hemoglobin immobilized in CuO nanowire bundles. Talanta 2010; 83:162-6. [DOI: 10.1016/j.talanta.2010.08.056] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2010] [Revised: 08/28/2010] [Accepted: 08/30/2010] [Indexed: 11/24/2022]
|
28
|
Xu S, Zhang X, Wan T, Zhang C. A third-generation hydrogen peroxide biosensor based on horseradish peroxidase cross-linked to multi-wall carbon nanotubes. Mikrochim Acta 2010. [DOI: 10.1007/s00604-010-0479-x] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
29
|
Pirillo S, Einschlag FSG, Ferreira ML, Rueda EH. Eriochrome Blue Black R and Fluorescein degradation by hydrogen peroxide oxidation with horseradish peroxidase and hematin as biocatalysts. ACTA ACUST UNITED AC 2010. [DOI: 10.1016/j.molcatb.2010.03.003] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
30
|
Sousa CP, Polo AS, Torresi RM, de Torresi SIC, Alves WA. Chemical modification of a nanocrystalline TiO2 film for efficient electric connection of glucose oxidase. J Colloid Interface Sci 2010; 346:442-7. [DOI: 10.1016/j.jcis.2010.03.036] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2010] [Revised: 03/15/2010] [Accepted: 03/17/2010] [Indexed: 11/15/2022]
|
31
|
Puiu M, Constantinovici M, Babaligea I, Raducan A, Olmazu C, Oancea D. Detecting Operational Inactivation of Horseradish Peroxidase using an Isoconversional Method. Chem Eng Technol 2010. [DOI: 10.1002/ceat.200900328] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
32
|
Abstract
Once activated by hydrogen peroxide, horseradish peroxidase (HRP) catalyzes the oxidation of aqueous aromatic compounds to produce high molecular weight polymers of low solubility. A pseudo steady-state kinetic model of the HRP-hydrogen peroxide-aromatic compound system was modified to incorporate enzyme inactivation mechanisms in order to improve its predictive ability. The kinetic constants of the model were calibrated using a series of experimental data sets. The model's ability to predict the time-dependent removal of phenol within the range of 0.5-6 mM from a batch reactor was validated. The model accounts for permanent losses of enzyme activity through inactivation by free radicals as well as interaction with end-product polymers as they form.
Collapse
Affiliation(s)
- I D Buchanan
- Department of Civil Engineering and Applied Mechanics, McGill University, Montreal, Quebec H3A 2K6, Canada
| | | |
Collapse
|
33
|
Loading of myoglobin into layer-by-layer films assembled by concanavalin A and dextran based on their biospecific recognition: An electrochemical study. Electrochim Acta 2009. [DOI: 10.1016/j.electacta.2009.07.060] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
34
|
Shin S, Lee S, Davidson VL. Suicide inactivation of MauG during reaction with O(2) or H(2)O(2) in the absence of its natural protein substrate. Biochemistry 2009; 48:10106-12. [PMID: 19788236 DOI: 10.1021/bi901284e] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
MauG is a diheme protein that catalyzes the six-electron oxidation of a biosynthetic precursor protein of methylamine dehydrogenase (PreMADH) with partially synthesized tryptophan tryptophylquinone (TTQ) to yield the mature protein with the functional protein-derived TTQ cofactor. The biosynthetic reaction proceeds via a relatively stable high valent bis-Fe(IV) intermediate. Oxidizing equivalents ([O]) for this reaction may be provided by either O(2) plus electrons from an external donor or H(2)O(2). The presence or absence of PreMADH has no influence on the reactivity of MauG with [O]; however, it is demonstrated that MauG is inactivated when supplied with [O] in the absence of PreMADH. The mechanism of inactivation appears to differ depending on the source of [O]. Repeated reaction of diferrous MauG with O(2) leads to loss of activity but not inactivation of heme, as judged by absorption spectroscopy and pyridine hemochrome assay. Repeated reaction of diferric MauG with H(2)O(2) leads to loss of activity and inactivation of heme, as well as some covalent cross-linking of MauG molecules. None of these deleterious effects with either source of [O] are observed when PreMADH is present to react with MauG. The radical scavenger hydroxyurea and small molecule mimics of the monohydroxylated Trp residue of PreMADH also reacted with bis-Fe(IV) MauG and afforded protection against inactivation. These results demonstrate that while O(2) and H(2)O(2) readily react with MauG in the absence of PreMADH, the presence of this substrate is necessary to prevent suicide inactivation of MauG after formation of the bis-Fe(IV) intermediate.
Collapse
Affiliation(s)
- Sooim Shin
- Department of Biochemistry, The University of Mississippi Medical Center, Jackson, Mississippi 39216, USA
| | | | | |
Collapse
|
35
|
Frasconi M, Rea S, Matricardi P, Favero G, Mazzei F. Scleroglucan-borax hydrogel: a flexible tool for redox protein immobilization. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2009; 25:11097-11104. [PMID: 19694483 DOI: 10.1021/la901245z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
A highly stable biological film was prepared by casting an aqueous dispersion of protein and composite hydrogel obtained from the polysaccharide Scleroglucan (Sclg) and borax as a cross-linking agent. Heme proteins, such as hemoglobin (Hb), myoglobin (Mb), and horseradish peroxidase (HRP), were chosen as model proteins to investigate the immobilized system. A pair of well-defined quasi-reversible redox peaks, characteristics of the protein heme FeII/FeIII redox couples, were obtained at the Sclg-borax/proteins films on pyrolytic graphite (PG) electrodes, as a consequence of the direct electron transfer between the protein and the PG electrode. A full characterization of the electron transfer kinetic was performed by opportunely modeling data obtained from cyclic voltammetry and square wave voltammetry experiments. The efficiency of our cross-linking approach was investigated by studying the influence of different borax groups percentage in the Sclg matrix, revealing the versatility of this hydrogel in the immobilization of redox proteins. The native conformation of the three heme proteins entrapped in the hydrogel films were proved to be unchanged, reflected by the unaltered Soret adsorption band and by the catalytic activity toward hydrogen peroxide (H2O2). The main kinetic parameters, such as the apparent Michaelis-Menten constant, for the electrocatalytic reaction were also evaluated. The peculiar characteristics of Sclg-borax matrix make it possible to find wide opportunities as proteins immobilizing agent for studies of direct electrochemistry and biosensors development.
Collapse
Affiliation(s)
- Marco Frasconi
- Department of Chemistry and Drug Technologies, Sapienza University of Rome, P.le Aldo Moro, 5 00185 Rome, Italy
| | | | | | | | | |
Collapse
|
36
|
Novel Protocol for Covalent Immobilization of Horseradish Peroxidase on Gold Electrode Surface. ELECTROANAL 2009. [DOI: 10.1002/elan.200804466] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
37
|
Kukavica B, Mojovic M, Vuccinic Z, Maksimovic V, Takahama U, Jovanovic SV. Generation of hydroxyl radical in isolated pea root cell wall, and the role of cell wall-bound peroxidase, Mn-SOD and phenolics in their production. PLANT & CELL PHYSIOLOGY 2009; 50:304-17. [PMID: 19098072 DOI: 10.1093/pcp/pcn199] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
The hydroxyl radical produced in the apoplast has been demonstrated to facilitate cell wall loosening during cell elongation. Cell wall-bound peroxidases (PODs) have been implicated in hydroxyl radical formation. For this mechanism, the apoplast or cell walls should contain the electron donors for (i) H(2)O(2) formation from dioxygen; and (ii) the POD-catalyzed reduction of H(2)O(2) to the hydroxyl radical. The aim of the work was to identify the electron donors in these reactions. In this report, hydroxyl radical (.OH) generation in the cell wall isolated from pea roots was detected in the absence of any exogenous reductants, suggesting that the plant cell wall possesses the capacity to generate .OH in situ. Distinct POD and Mn-superoxide dismutase (Mn-SOD) isoforms different from other cellular isoforms were shown by native gel electropho-resis to be preferably bound to the cell walls. Electron paramagnetic resonance (EPR) spectroscopy of cell wall isolates containing the spin-trapping reagent, 5-diethoxyphosphoryl-5-methyl-1-pyrroline-N-oxide (DEPMPO), was used for detection of and differentiation between .OH and the superoxide radical (O(2)(-).). The data obtained using POD inhibitors confirmed that tightly bound cell wall PODs are involved in DEPMPO/OH adduct formation. A decrease in DEPMPO/OH adduct formation in the presence of H(2)O(2) scavengers demonstrated that this hydroxyl radical was derived from H(2)O(2). During the generation of .OH, the concentration of quinhydrone structures (as detected by EPR spectroscopy) increased, suggesting that the H(2)O(2) required for the formation of .OH in isolated cell walls is produced during the reduction of O(2) by hydroxycinnamic acids. Cell wall isolates in which the proteins have been denaturated (including the endogenous POD and SOD) did not produce .OH. Addition of exogenous H(2)O(2) again induced the production of .OH, and these were shown to originate from the Fenton reaction with tightly bound metal ions. However, the appearance of the DEPMPO/OOH adduct could also be observed, due to the production of O(2)(-). when endogenous SOD has been inactivated. Also, O(2)(-). was converted to .OH in an in vitro horseradish peroxidase (HRP)/H(2)O(2) system to which exogenous SOD has been added. Taken together with the discovery of the cell wall-bound Mn-SOD isoform, these results support the role of such a cell wall-bound SOD in the formation of .OH jointly with the cell wall-bound POD. According to the above findings, it seems that the hydroxycinnamic acids from the cell wall, acting as reductants, contribute to the formation of H(2)O(2) in the presence of O(2) in an autocatalytic manner, and that POD and Mn-SOD coupled together generate .OH from such H(2)O(2).
Collapse
|
38
|
|
39
|
Gil‐Rodríguez P, Ferreira‐Batista C, Vázquez‐Duhalt R, Valderrama B. A Novel Heme Peroxidase fromRaphanus sativusIntrinsically Resistant to Hydrogen Peroxide. Eng Life Sci 2008. [DOI: 10.1002/elsc.200700073] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
|
40
|
Rich PR, Iwaki M. A comparison of catalytic site intermediates of cytochrome c oxidase and peroxidases. BIOCHEMISTRY (MOSCOW) 2008; 72:1047-55. [PMID: 18021063 DOI: 10.1134/s0006297907100033] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Compounds I and II of peroxidases such as horseradish peroxidase and cytochrome c peroxidase are relatively well understood catalytic intermediates in terms of their structures and redox states of iron, heme, and associated radical species. The intermediates involved in the oxygen reduction chemistry of the cytochrome c oxidase superfamily are more complicated because of the need for four reducing equivalents and because of the linkage of the oxygen chemistry with vectorial proton translocations. Nevertheless, two of these intermediates, the peroxy and ferryl forms, have characteristics that can in many ways be considered to be counterparts of peroxidase compounds I and II. We explore the primary factors that minimize the generation of unwanted reactive oxygen species products and ensure that the principal enzymological function becomes either that of a peroxidase or an oxidase. These comparisons can provide insights into the nature of biological oxygen reduction chemistry and guidance for the engineering of biomimetic synthetic materials.
Collapse
Affiliation(s)
- P R Rich
- Glynn Laboratory of Bioenergetics, Department of Biology, University College London, London WC1E 6BT, UK.
| | | |
Collapse
|
41
|
Nicholls P. The oxygenase-peroxidase theory of Bach and Chodat and its modern equivalents: change and permanence in scientific thinking as shown by our understanding of the roles of water, peroxide, and oxygen in the functioning of redox enzymes. BIOCHEMISTRY (MOSCOW) 2008; 72:1039-46. [PMID: 18021062 DOI: 10.1134/s0006297907100021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Alexander Bach was both revolutionary politician and biochemist. His earliest significant publication, "Tsar-golod" ("The Tsar of Hunger"), introduced Marxist thought to Russian workers. In exile for 30 years, he moved to study the dialectic of the oxidases. When his theory of oxidases as combinations of oxygenases and peroxidases was developed (circa 1900) the enzyme concept was not fully formulated, and the enzyme/substrate distinction not yet made. Peroxides however were then and remain now significant intermediates, when either free or bound, in oxidase catalyses. The aerobic dehydrogenase/peroxidase/catalase coupled systems which were studied slightly later clarified the Bach model and briefly became an oxidase paradigm. Identification of peroxidase as a metalloprotein, a key step in understanding oxidase and peroxidase mechanisms, postdated Bach's major work. Currently we recognize catalytic organic peroxides in flavoprotein oxygenases; such organic peroxides are also involved in lipid oxidation and tryptophan radical decay. But most physiologically important peroxides are now known to be bound to transition metals (either Fe or Cu) and formed both directly and indirectly (from oxygen). The typical stable metalloprotein peroxide product is the ferryl state. When both peroxide oxidizing equivalents are retained the second equivalent is held as a protein or porphyrin radical. True metal peroxide complexes are unstable. But often water molecules mark the spot where the original peroxide decayed. The cytochrome c oxidase Fe-Cu center can react with either peroxide or oxygen to form the intermediate higher oxidation states P and F. In its resting state water molecules and hydroxyl ions can be seen marking the original location of the oxygen or peroxide molecule.
Collapse
Affiliation(s)
- P Nicholls
- Department of Biological Sciences, Essex University, Colchester, Essex, CO 4 3SQ, UK.
| |
Collapse
|
42
|
Zhu L, Yang R, Zhai J, Tian C. Bienzymatic glucose biosensor based on co-immobilization of peroxidase and glucose oxidase on a carbon nanotubes electrode. Biosens Bioelectron 2007; 23:528-35. [DOI: 10.1016/j.bios.2007.07.002] [Citation(s) in RCA: 120] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2007] [Revised: 07/06/2007] [Accepted: 07/11/2007] [Indexed: 10/23/2022]
|
43
|
Zhang H, Hu N. Assembly of myoglobin layer-by-layer films with poly(propyleneimine) dendrimer-stabilized gold nanoparticles and its application in electrochemical biosensing. Biosens Bioelectron 2007; 23:393-9. [PMID: 17561388 DOI: 10.1016/j.bios.2007.04.018] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2007] [Revised: 04/12/2007] [Accepted: 04/30/2007] [Indexed: 11/17/2022]
Abstract
The small-sized Au nanoparticles (3 nm) were prepared by reduction of HAuCl(4) in the presence of poly(propyleneimine) (PPI) dendrimers, forming the stable PPI-Au nanoclusters in aqueous medium. The PPI-Au nanoclusters might take a kind of "core-shell" structure, in which several PPI molecules were attached on the surface of one gold nanoparticle. The PPI-Au nanoclusters in aqueous dispersions and myoglobin (Mb) in its buffers at pH 5.0 were then alternately adsorbed on the surface of pyrolytic graphite (PG) electrodes and other solid substrates, forming {PPI-Au/Mb}(n) layer-by-layer films, which was confirmed by cyclic voltammetry (CV) and quartz crystal microbalance (QCM). {PPI-Au/Mb}(n) films on PG electrodes demonstrated a pair of well-defined and quasi-reversible CV reduction-oxidation peaks for Mb heme Fe(III)/Fe(II) couple and good electrocatalytic properties toward reduction of oxygen and hydrogen peroxide. Compared with {Au/Mb}(n) multilayer films containing no dendrimers and {PAMAM/Mb}(n) films assembled by polyamidoamine (PAMAM) dendrimers and Mb but in the absence of Au nanoparticles, {PPI-Au/Mb}(n) films showed better electrochemical behaviors and catalytic performances, which may be attributed to the unique structure of PPI-Au nanoclusters and good conductivity of gold nanoparticles. This novel kind of protein multilayer films assembled with dendrimer-stabilized gold nanoparticles may provide a new and general approach to fabricate the biosensors and bioreactors based on the direct electrochemistry of proteins or enzymes.
Collapse
Affiliation(s)
- Hong Zhang
- Department of Chemistry, Beijing Normal University, Beijing 100875, PR China
| | | |
Collapse
|
44
|
Guo W, Hu N. Interaction of myoglobin with poly(methacrylic acid) at different pH in their layer-by-layer assembly films: an electrochemical study. Biophys Chem 2007; 129:163-71. [PMID: 17566631 DOI: 10.1016/j.bpc.2007.05.015] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2007] [Revised: 05/24/2007] [Accepted: 05/25/2007] [Indexed: 11/22/2022]
Abstract
Myoglobin (Mb), with net positive surface charges at pH 5.0, was successfully assembled into layer-by-layer films on various solid surfaces with poly(methacrylic acid) (PMAA) at different pH, designated as {PMAA(pH 5.0)/Mb}n, {PMAA(pH 6.5)/Mb}n, and {PMAA(pH 8.0)/Mb}n, respectively. As a weak polycarboxylic acid with pKa=6 - 7, PMAA carried different negative charges at different pH due to different ionization degree of its carboxylic acid groups. Quartz crystal microbalance (QCM), UV-vis spectroscopy, and cyclic voltammetry (CV) were used to monitor and confirm the assembly of {PMAA/Mb}n films. All the results showed that the adsorption amount of Mb in each bilayer had an "unexpected" sequence of {PMAA(pH 5.0)/Mb}n>{PMAA(pH 6.5)/Mb}n>{PMAA(pH 8.0)/Mb}n, which could be explained by the formation of soluble complex of PMAA-Mb at pH 8.0 and the cooperative effect of hydrogen bonding and induced electrostatic interaction between Mb and PMAA at pH 5.0. The influence of ionic strength in exposure solution and in Mb adsorbate solution was investigated, and the results supported the above explanations. The {PMAA/Mb}n films provided a suitable microenvironment for Mb to retain its near-native structure and transfer electron with underlying electrodes. The reversible CV peak pair for Mb Fe(III)/Fe(II) redox couple could be used to catalyze reduction of hydrogen peroxide electrochemically, showing the potential applicability of the films as the new type of biosensors or bioreactors based on the direct electrochemistry of Mb. The electrochemical and electrocatalytic behaviors of protein layer-by-layer films with weak polyelectrolytes could thus be controlled by adjusting the solution pH of weak polyelectrolytes.
Collapse
Affiliation(s)
- Wei Guo
- Department of Chemistry, Beijing Normal University, Beijing 100875, China
| | | |
Collapse
|
45
|
Smulevich G, Jakopitsch C, Droghetti E, Obinger C. Probing the structure and bifunctionality of catalase-peroxidase (KatG). J Inorg Biochem 2006; 100:568-85. [PMID: 16516299 DOI: 10.1016/j.jinorgbio.2006.01.033] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2005] [Revised: 01/12/2006] [Accepted: 01/12/2006] [Indexed: 10/24/2022]
Abstract
Catalase-peroxidases (KatGs) exhibit peroxidase and substantial catalase activities similar to monofunctional catalases. Crystal structures of four different KatGs reveal the presence of a peroxidase-conserved proximal and distal heme pocket together with features unique to KatG. To gain insight into their structure-function properties, many variants were produced and very similar results were obtained irrespective of the origin of the KatG mutated. This review focuses mainly on the electronic absorption and resonance Raman results together with the combined analysis of pre-steady and steady-state kinetics of various mutants involving both the peroxidase-conserved and the KatG-specific residues of recombinant KatG from the cyanobacterium Synechocystis. Marked differences in the structural role of conserved amino acids and hydrogen-bond networks in KatG with respect to the other plant peroxidases were found. Typically, the catalatic but not the peroxidatic activity was very sensitive to mutations that disrupted the KatG-typical extensive hydrogen-bonding network. Moreover, the integrity of this network is crucial for the formation of distinct protein radicals formed upon incubation of KatG with peroxides in the absence of one-electron donors. The correlation between the structural architecture and the bifunctional activity is discussed and compared with data obtained for KatGs from other organisms.
Collapse
Affiliation(s)
- Giulietta Smulevich
- Dipartimento di Chimica, Università di Firenze, Via della Lastruccia 3, I-50019 Sesto Fiorentino, Florence, Italy.
| | | | | | | |
Collapse
|
46
|
Abstract
Oxidoreductase enzymes catalyze single- or multi-electron reduction/oxidation reactions of small molecule inorganic or organic substrates, and they are integral to a wide variety of biological processes including respiration, energy production, biosynthesis, metabolism, and detoxification. All redox enzymes require a natural redox partner such as an electron-transfer protein (e.g. cytochrome, ferredoxin, flavoprotein) or a small molecule cosubstrate (e.g. NAD(P)H, dioxygen) to sustain catalysis, in effect to balance the substrate/product redox half-reaction. In principle, the natural electron-transfer partner may be replaced by an electrochemical working electrode. One of the great strengths of this approach is that the rate of catalysis (equivalent to the observed electrochemical current) may be probed as a function of applied potential through linear sweep and cyclic voltammetry, and insight to the overall catalytic mechanism may be gained by a systematic electrochemical study coupled with theoretical analysis. In this review, the various approaches to enzyme electrochemistry will be discussed, including direct and indirect (mediated) experiments, and a brief coverage of the theory relevant to these techniques will be presented. The importance of immobilizing enzymes on the electrode surface will be presented and the variety of ways that this may be done will be reviewed. The importance of chemical modification of the electrode surface in ensuring an environment conducive to a stable and active enzyme capable of functioning natively will be illustrated. Fundamental research into electrochemically driven enzyme catalysis has led to some remarkable practical applications. The glucose oxidase enzyme electrode is a spectacularly successful application of enzyme electrochemistry. Biosensors based on this technology are used worldwide by sufferers of diabetes to provide rapid and accurate analysis of blood glucose concentrations. Other applications of enzyme electrochemistry are in the sensing of macromolecular complexation events such as antigen–antibody binding and DNA hybridization. The review will include a selection of enzymes that have been successfully investigated by electrochemistry and, where appropriate, discuss their development towards practical biotechnological applications.
Collapse
|
47
|
Ling KQ, Sayre LM. Horseradish peroxidase-mediated aerobic and anaerobic oxidations of 3-alkylindoles. Bioorg Med Chem 2005; 13:3543-51. [PMID: 15848767 DOI: 10.1016/j.bmc.2005.02.013] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2004] [Revised: 02/05/2005] [Accepted: 02/09/2005] [Indexed: 11/29/2022]
Abstract
Little is known about the HRP-mediated oxidations of 3-alkylindoles. Whereas 3-methylindole and 3-ethylindole were found to be turned over smoothly by HRP, reactions of tryptophol and N-acetyltryptamine were inefficient. Oxidations of the former two indoles by HRP under aerobic conditions led to the corresponding ring-opened o-acylformanilides and oxindoles, whereas anaerobic oxidations resulted in oxidative dimerization. The major products of anaerobic oxidation of 3-methylindole were shown to be two hydrated dimers, while anhydrodimers were obtained in the 3-ethyl case. The proposed mechanism involves HRP-mediated one-electron oxidation to give an indole radical that either dimerizes (anaerobic conditions) or reacts with O2 (aerobic conditions). Measured kinetics of indole oxidation by HRP compounds I and II mirrored their relative reactivities under turnover conditions. The observed comparable binding affinities for all four indole substrates investigated suggest that the low reactivity of tryptophol and N-acetyltryptamine reflect binding to HRP in an orientation that is disadvantageous to electron transfer oxidation of the indole ring.
Collapse
Affiliation(s)
- Ke-Qing Ling
- Department of Chemistry, Case Western Reserve University, Cleveland, OH 44106, USA
| | | |
Collapse
|
48
|
Liu Y, Wang M, Zhao F, Guo Z, Chen H, Dong S. Direct electron transfer and electrocatalysis of microperoxidase immobilized on nanohybrid film. J Electroanal Chem (Lausanne) 2005. [DOI: 10.1016/j.jelechem.2005.01.022] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
49
|
Synthesis of polycardanol from a renewable resource using a fungal peroxidase from Coprinus cinereus. ACTA ACUST UNITED AC 2005. [DOI: 10.1016/j.molcatb.2005.04.005] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
|
50
|
Santos A, Durán N, Kubota L. Biosensor for H2O2 Response Based on Horseradish Peroxidase: Effect of Different Mediators Adsorbed on Silica Gel Modified with Niobium Oxide. ELECTROANAL 2005. [DOI: 10.1002/elan.200403222] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|