1
|
Liu X, Zhang Q, Li M, Qin S, Zhao Z, Lin B, Ding Y, Xiang Y, Li C. Horseradish peroxidase (HRP) and glucose oxidase (GOX) based dual-enzyme system: Sustainable release of H 2O 2 and its effect on the desirable ping pong bibi degradation mechanism. ENVIRONMENTAL RESEARCH 2023; 229:115979. [PMID: 37119847 DOI: 10.1016/j.envres.2023.115979] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Revised: 03/13/2023] [Accepted: 04/22/2023] [Indexed: 05/05/2023]
Abstract
In this study, an adaptable HRP/GOX-Glu system was established due to the trait, efficient degradation of pollutants in the catalytic process of HRP named the ping-pong bibi mechanism and a sustained release of H2O2 in-situ under the catalysis of glucose oxidase (GOX). Compared with the traditional HRP/H2O2 system, the HRP was more stable in the HRP/GOX-Glu system based on the feature of persistent releasing H2O2 in-situ. Simultaneously, the high valent iron was found out to give a greater contribution to Alizarin Green (AG) removal through ping-pong mechanism, whereas the hydroxyl radical and superoxide free radical generated by Bio-Fenton were also the main active substances for AG degradation. Furthermore, on the basis of effect evaluation of the co-existence of two different degradation mechanisms in the HRP/GOX-Glu system, the degradation pathways of AG were proposed. Moreover, the optimum reaction conditions preferentially triggering ping-pong bibi mechanism instead of Bio-Fenton were determined by single factor analysis and degradation mechanism elaboration. This study would provide a reference for how to give full play to the advantages of ping-pong bibi mechanism in the dual-enzyme system based on HRP to degrade pollutants with high efficiency.
Collapse
Affiliation(s)
- Xiangyu Liu
- School of Civil Engineering & Architecture, Wuhan University of Technology, 122 Luoshi Road, Wuhan, 430070, China
| | - Qian Zhang
- School of Civil Engineering & Architecture, Wuhan University of Technology, 122 Luoshi Road, Wuhan, 430070, China; Shenzhen Research Institute of Wuhan University of Technology, Shenzhen, 518000, China
| | - Meng Li
- School of Civil Engineering & Architecture, Wuhan University of Technology, 122 Luoshi Road, Wuhan, 430070, China; Shenzhen Research Institute of Wuhan University of Technology, Shenzhen, 518000, China
| | - Song Qin
- School of Art and Design, Wuhan University of Technology, 122 Luoshi Road, Wuhan, 430070, China.
| | - Ziqi Zhao
- School of Civil Engineering & Architecture, Wuhan University of Technology, 122 Luoshi Road, Wuhan, 430070, China
| | - Bing Lin
- School of Civil Engineering & Architecture, Wuhan University of Technology, 122 Luoshi Road, Wuhan, 430070, China
| | - Yuwei Ding
- School of Civil Engineering & Architecture, Wuhan University of Technology, 122 Luoshi Road, Wuhan, 430070, China
| | - Yutong Xiang
- School of Civil Engineering & Architecture, Wuhan University of Technology, 122 Luoshi Road, Wuhan, 430070, China
| | - Chengwei Li
- Hunan Land and Resources Exploration Institute, Changsha, 410001, China
| |
Collapse
|
2
|
Yayci A, Bachmann N, Dirks T, Hofmann E, Bandow JE. Characterization of three novel DyP-type peroxidases from Streptomyces chartreusis NRRL 3882. J Appl Microbiol 2022; 133:2417-2429. [PMID: 35808848 DOI: 10.1111/jam.15707] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Revised: 06/29/2022] [Accepted: 07/05/2022] [Indexed: 11/29/2022]
Abstract
AIMS Actinobacteria are known to produce extracellular enzymes including DyPs. We set out to identify and characterize novel peroxidases from Streptomyces chartreusis NRRL 3882, because S. chartreusis belongs to the small group of actinobacteria with three different DyPs. METHODS AND RESULTS The genome of the actinomycete Streptomyces chartreusis NRRL 3882 was mined for novel DyP-type peroxidases. Three genes encoding for DyP-type peroxidases were cloned and overexpressed in Escherichia coli. Subsequent characterization of the recombinant proteins included examination of operating conditions such as pH, temperature, and H2 O2 concentrations, as well as substrate spectrum. Despite their high sequence similarity, the enzymes named SCDYP1-SCDYP3 presented distinct preferences regarding their operating conditions. They showed great divergence in H2 O2 tolerance and stability, with SCDYP2 being most active at concentrations above 50 mmol l-1 . Moreover, SCDYP1 and SCDYP3 preferred acidic pH (typical for DyP-type peroxidases) whereas SCDYP2 was most active at pH 8. CONCLUSIONS Regarding the function of DyPs in nature, these results suggest that availability of different DyP variants with complementary activity profiles in one organism might convey evolutionary benefits. SIGNIFICANCE AND IMPACT OF STUDY DyP-type peroxidases are able to degrade xenobiotic compounds and thus can be applied in biocatalysis and bioremediation. However, the native function of DyPs and the benefits for their producers largely remain to be elucidated.
Collapse
Affiliation(s)
- Abdulkadir Yayci
- Applied Microbiology, Faculty of Biology and Biotechnology, Ruhr University Bochum, Germany
| | - Nathalie Bachmann
- Applied Microbiology, Faculty of Biology and Biotechnology, Ruhr University Bochum, Germany
| | - Tim Dirks
- Applied Microbiology, Faculty of Biology and Biotechnology, Ruhr University Bochum, Germany
| | - Eckhard Hofmann
- Protein Crystallography, Faculty of Biology and Biotechnology, Ruhr University Bochum, Germany
| | - Julia E Bandow
- Applied Microbiology, Faculty of Biology and Biotechnology, Ruhr University Bochum, Germany
| |
Collapse
|
3
|
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]
|
4
|
Queiroz RF, Stanley CP, Wolhuter K, Kong SMY, Rajivan R, McKinnon N, Nguyen GTH, Roveri A, Guttzeit S, Eaton P, Donald WA, Ursini F, Winterbourn CC, Ayer A, Stocker R. Hydrogen peroxide signaling via its transformation to a stereospecific alkyl hydroperoxide that escapes reductive inactivation. Nat Commun 2021; 12:6626. [PMID: 34785665 PMCID: PMC8595612 DOI: 10.1038/s41467-021-26991-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Accepted: 10/28/2021] [Indexed: 11/16/2022] Open
Abstract
During systemic inflammation, indoleamine 2,3-dioxygenase 1 (IDO1) becomes expressed in endothelial cells where it uses hydrogen peroxide (H2O2) to oxidize L-tryptophan to the tricyclic hydroperoxide, cis-WOOH, that then relaxes arteries via oxidation of protein kinase G 1α. Here we show that arterial glutathione peroxidases and peroxiredoxins that rapidly eliminate H2O2, have little impact on relaxation of IDO1-expressing arteries, and that purified IDO1 forms cis-WOOH in the presence of peroxiredoxin 2. cis-WOOH oxidizes protein thiols in a selective and stereospecific manner. Compared with its epimer trans-WOOH and H2O2, cis-WOOH reacts slower with the major arterial forms of glutathione peroxidases and peroxiredoxins while it reacts more readily with its target, protein kinase G 1α. Our results indicate a paradigm of redox signaling by H2O2 via its enzymatic conversion to an amino acid-derived hydroperoxide that 'escapes' effective reductive inactivation to engage in selective oxidative activation of key target proteins.
Collapse
Affiliation(s)
- Raphael F Queiroz
- Department of Natural Sciences, Southwest Bahia State University, Vitoria da Conquista, Bahia, Brazil
- Victor Chang Cardiac Research Institute, Darlinghurst, New South Wales, Australia
| | - Christopher P Stanley
- Victor Chang Cardiac Research Institute, Darlinghurst, New South Wales, Australia
- Heart Research Institute, The University of Sydney, Sydney, Australia
| | - Kathryn Wolhuter
- Victor Chang Cardiac Research Institute, Darlinghurst, New South Wales, Australia
| | | | - Ragul Rajivan
- Victor Chang Cardiac Research Institute, Darlinghurst, New South Wales, Australia
| | - Naomi McKinnon
- Victor Chang Cardiac Research Institute, Darlinghurst, New South Wales, Australia
| | - Giang T H Nguyen
- School of Chemistry, University of New South Wales, Sydney, New South Wales, Australia
| | - Antonella Roveri
- Department of Molecular Medicine, University of Padova, Padova, Italy
| | | | - Philip Eaton
- William Harvey Research Institute, Barts and the London School of Medicine, Queen Mary University of London, London, UK
| | - William A Donald
- School of Chemistry, University of New South Wales, Sydney, New South Wales, Australia
| | - Fulvio Ursini
- Department of Molecular Medicine, University of Padova, Padova, Italy
| | - Christine C Winterbourn
- Centre for Free Radical Research, Department of Pathology, University of Otago Christchurch, Christchurch, New Zealand
| | - Anita Ayer
- Victor Chang Cardiac Research Institute, Darlinghurst, New South Wales, Australia.
- Heart Research Institute, The University of Sydney, Sydney, Australia.
- St Vincent's Clinical School, University of New South Wales, Sydney, New South Wales, Australia.
| | - Roland Stocker
- Victor Chang Cardiac Research Institute, Darlinghurst, New South Wales, Australia.
- Heart Research Institute, The University of Sydney, Sydney, Australia.
- St Vincent's Clinical School, University of New South Wales, Sydney, New South Wales, Australia.
- School of Life and Environmental Sciences, The University of Sydney, Sydney, Australia.
| |
Collapse
|
5
|
The steadfast Au@Pt soldier: Peroxide-tolerant nanozyme for signal enhancement in lateral flow immunoassay of peroxidase-containing samples. Talanta 2021; 225:121961. [DOI: 10.1016/j.talanta.2020.121961] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Revised: 11/25/2020] [Accepted: 11/30/2020] [Indexed: 02/05/2023]
|
6
|
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
|
7
|
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
|
8
|
Ciaramella A, Catucci G, Di Nardo G, Sadeghi SJ, Gilardi G. Peroxide-driven catalysis of the heme domain of A. radioresistens cytochrome P450 116B5 for sustainable aromatic rings oxidation and drug metabolites production. N Biotechnol 2020; 54:71-79. [DOI: 10.1016/j.nbt.2019.08.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Revised: 08/22/2019] [Accepted: 08/23/2019] [Indexed: 02/08/2023]
|
9
|
Dai H, Lü W, Zuo X, Zhu Q, Pan C, Niu X, Liu J, Chen H, Chen X. A novel biosensor based on boronic acid functionalized metal-organic frameworks for the determination of hydrogen peroxide released from living cells. Biosens Bioelectron 2017; 95:131-137. [DOI: 10.1016/j.bios.2017.04.021] [Citation(s) in RCA: 80] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Revised: 03/23/2017] [Accepted: 04/17/2017] [Indexed: 01/18/2023]
|
10
|
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
|
11
|
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
|
12
|
Zheng X, Sun H, Hou S. Electroactive Film of Myoglobin Incorporated in a 3D-porous Calcium Alginate Film with Polyvinyl Alcohol, Glycerin and Gelatin. ANAL SCI 2015; 31:1241-7. [PMID: 26656812 DOI: 10.2116/analsci.31.1241] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
In this work, an electroactive porous Mb-CA's composite film was fabricated by incorporating myoglobin (Mb) in a three-dimension (3D) porous calcium alginate (CA) film with polyvinyl alcohol, glycerol, and gelatin. The porous Mb-CA's film modified electrodes exhibited a pair of well-defined, quasi-reversible cyclic voltammetric (CV) peaks at about -0.37 V vs. SCE in pH 7.0 buffers, characteristic of Mb heme Fe((III))/Fe((II)) redox couples. The electrochemical parameters, such as formal potentials (E(o')) and apparent heterogeneous electron-transfer rate constants (ks), were estimated by square-wave voltammetry with nonlinear regression analysis. The porous CA's composite film could form hydrogel in aqueous solution. The positions of the Soret absorbance band suggest that Mb in the CA's composite film kept its native states in the medium pH range. Hydrogen peroxide, oxygen, and nitrite were electrochemically catalyzed by the Mb-CA's composite film with significant lowering of the reduction overpotential.
Collapse
Affiliation(s)
- Xueqin Zheng
- Institute of Multifunctional Materials (IMM), Laboratory of New Fiber Materials and Modern Textile, College of Chemical Science and Engineering, Qingdao University
| | | | | |
Collapse
|
13
|
Bernardes A, Textor LC, Santos JC, Cuadrado NH, Kostetsky EY, Roig MG, Bavro VN, Muniz JR, Shnyrov VL, Polikarpov I. Crystal structure analysis of peroxidase from the palm tree Chamaerops excelsa. Biochimie 2015; 111:58-69. [DOI: 10.1016/j.biochi.2015.01.014] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2014] [Accepted: 01/25/2015] [Indexed: 11/24/2022]
|
14
|
Pradal C, Grøndahl L, Cooper-White JJ. Hydrolytically Degradable Polyrotaxane Hydrogels for Drug and Cell Delivery Applications. Biomacromolecules 2014; 16:389-403. [DOI: 10.1021/bm501615p] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
|
15
|
Kim SJ, Joo JC, Song BK, Yoo YJ, Kim YH. Engineering a horseradish peroxidase C stable to radical attacks by mutating multiple radical coupling sites. Biotechnol Bioeng 2014; 112:668-76. [PMID: 25335829 DOI: 10.1002/bit.25483] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2014] [Revised: 09/27/2014] [Accepted: 10/13/2014] [Indexed: 12/07/2022]
Abstract
Peroxidases have great potential as industrial biocatalysts. In particular, the oxidative polymerization of phenolic compounds catalyzed by peroxidases has been extensively examined because of the advantage of this method over other conventional chemical methods. However, the industrial application of peroxidases is often limited because of their rapid inactivation by phenoxyl radicals during oxidative polymerization. In this work, we report a novel protein engineering approach to improve the radical stability of horseradish peroxidase isozyme C (HRPC). Phenylalanine residues that are vulnerable to modification by the phenoxyl radicals were identified using mass spectrometry analysis. UV-Vis and CD spectra showed that radical coupling did not change the secondary structure or the active site of HRPC. Four phenylalanine (Phe) residues (F68, F142, F143, and F179) were each mutated to alanine residues to generate single mutants to examine the role of these sites in radical coupling. Despite marginal improvement of radical stability, each single mutant still exhibited rapid radical inactivation. To further reduce inactivation by radical coupling, the four substitution mutations were combined in F68A/F142A/F143A/F179A. This mutant demonstrated dramatic enhancement of radical stability by retaining 41% of its initial activity compared to the wild-type, which was completely inactivated. Structure and sequence alignment revealed that radical-vulnerable Phe residues of HPRC are conserved in homologous peroxidases, which showed the same rapid inactivation tendency as HRPC. Based on our site-directed mutagenesis and biochemical characterization, we have shown that engineering radical-vulnerable residues to eliminate multiple radical coupling can be a good strategy to improve the stability of peroxidases against radical attack.
Collapse
Affiliation(s)
- Su Jin Kim
- Interdisciplinary Program of Bioengineering, School of Chemical and Biological Engineering, Seoul National University, Seoul, 151-742, Korea; Korea Research Institute of Chemical Technology, Daejeon, 305-600, Korea
| | | | | | | | | |
Collapse
|
16
|
Kim SJ, Joo JC, Kim HS, Kwon I, Song BK, Yoo YJ, Kim YH. Development of the radical-stable Coprinus cinereus peroxidase (CiP) by blocking the radical attack. J Biotechnol 2014; 189:78-85. [DOI: 10.1016/j.jbiotec.2014.08.040] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2014] [Revised: 08/23/2014] [Accepted: 08/27/2014] [Indexed: 11/26/2022]
|
17
|
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]
|
18
|
Njuma OJ, Ndontsa EN, Goodwin DC. Catalase in peroxidase clothing: Interdependent cooperation of two cofactors in the catalytic versatility of KatG. Arch Biochem Biophys 2013; 544:27-39. [PMID: 24280274 DOI: 10.1016/j.abb.2013.11.007] [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: 09/15/2013] [Revised: 11/11/2013] [Accepted: 11/15/2013] [Indexed: 11/26/2022]
Abstract
Catalase-peroxidase (KatG) is found in eubacteria, archaea, and lower eukaryotae. The enzyme from Mycobacterium tuberculosis has received the greatest attention because of its role in activation of the antitubercular pro-drug isoniazid, and the high frequency with which drug resistance stems from mutations to the katG gene. Generally, the catalase activity of KatGs is striking. It rivals that of typical catalases, enzymes with which KatGs share no structural similarity. Instead, catalatic turnover is accomplished with an active site that bears a strong resemblance to a typical peroxidase (e.g., cytochrome c peroxidase). Yet, KatG is the only member of its superfamily with such capability. It does so using two mutually dependent cofactors: a heme and an entirely unique Met-Tyr-Trp (MYW) covalent adduct. Heme is required to generate the MYW cofactor. The MYW cofactor allows KatG to leverage heme intermediates toward a unique mechanism for H2O2 oxidation. This review evaluates the range of intermediates identified and their connection to the diverse catalytic processes KatG facilitates, including mechanisms of isoniazid activation.
Collapse
Affiliation(s)
- Olive J Njuma
- Department of Chemistry and Biochemistry, Auburn University, Auburn, AL 36849-5312, USA
| | - Elizabeth N Ndontsa
- Department of Chemistry and Biochemistry, Auburn University, Auburn, AL 36849-5312, USA
| | - Douglas C Goodwin
- Department of Chemistry and Biochemistry, Auburn University, Auburn, AL 36849-5312, USA.
| |
Collapse
|
19
|
Horseradish peroxidase inactivation: heme destruction and influence of polyethylene glycol. Sci Rep 2013; 3:3126. [PMID: 24185130 PMCID: PMC3816284 DOI: 10.1038/srep03126] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2013] [Accepted: 10/15/2013] [Indexed: 11/26/2022] Open
Abstract
Horseradish peroxidase (HRP) mediates efficient conversion of many phenolic contaminants and thus has potential applications for pollution control. Such potentially important applications suffer however from the fact that the enzyme becomes quickly inactivated during phenol oxidation and polymerization. The work here provides the first experimental data of heme consumption and iron releases to support the hypothesis that HRP is inactivated by heme destruction. Product of heme destruction is identified using liquid chromatography with mass spectrometry. The heme macrocycle destruction involving deprivation of the heme iron and oxidation of the 4-vinyl group in heme occurs as a result of the reaction. We also demonstrated that heme consumption and iron releases resulting from HRP destruction are largely reduced in the presence of polyethylene glycol (PEG), providing the first evidence to indicate that heme destruction is effectively suppressed by co-dissolved PEG. These findings advance a better understanding of the mechanisms of HRP inactivation.
Collapse
|
20
|
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
|
21
|
Abstract
From a generated PES, one can determine the relative energies of species involved, the sequence in which they occur, and the activation barrier(s) associated with individual steps or the overall mechanism. Furthermore, they can provide more insights than a simple indication of a path of sequential mechanistic structures and their energetic relationships. The investigation into the activation of O2 by alpha-ketoglutarate-dependent dioxygenase (AlkB) clearly shows the opportunity for spin inversion, where one can see that the lowest energy product may be formed via several possible routes. In the investigation of uroporphyrinogen decarboxylase III (UROD), the use of QM/MM methods allowed for the inclusion of the anisotropic protein environment providing greater insight into the rate-limiting barrier. Lastly, the mechanism of 6-phospho-α-glucosidase (GlvA) was discussed using different active site models. In particular, a continuum model PES was compared to the gas-phase PES.
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
|
Guo C, Sun H, Zhao X. Myoglobin within graphene oxide sheets and Nafion composite films as highly sensitive biosensor. SENSORS AND ACTUATORS. B, CHEMICAL 2012; 164:82-89. [PMID: 23576844 PMCID: PMC3617930 DOI: 10.1016/j.snb.2012.01.057] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2011] [Revised: 01/17/2012] [Accepted: 01/23/2012] [Indexed: 05/02/2023]
Abstract
A highly sensitive biosensor was fabricated by incorporating myoglobin (Mb) within graphene oxide (GO) sheets and Nafion composite films. The stable composite Mb-GO-Nafion films were characterized by electrochemistry, scanning electron microscopy, Fourier transform infrared spectroscopy and UV-vis spectroscopy. It was found that Mb in Mb-GO-Nafion films retained its secondary structure similar to its native states. Cyclic voltammetry of Mb-GO-Nafion films showed a pair of well defined, quasi-reversible peaks at about -0.312 V vs saturated calomel electrode (SCE) at pH 5.5, corresponding to direct electron transfer (DET) between Mb and the glassy carbon electrode. Electrochemical parameter of Mb in Mb-GO-Nafion film such as apparent heterogeneous electron transfer rate constant (ks) and formal potential (Eo') were obtained. The dependence of Eo' on solution pH indicated that the DET reaction of Mb was coupled with proton transfer. Mb in the films displayed good electrocatalytic activities towards various substrates such as hydrogen peroxide, nitrite and oxygen, indicating that the composite films have potential applications in fabricating novel biosensors without using mediators.
Collapse
Affiliation(s)
- Changchun Guo
- Institute of Multifunctional Materials (IMM), Laboratory of New Fiber Materials and Modern Textile, College of Chemistry, Chemical Engineering and Environment, Qingdao University, Qingdao 266071, China
| | - Hong Sun
- Institute of Multifunctional Materials (IMM), Laboratory of New Fiber Materials and Modern Textile, College of Chemistry, Chemical Engineering and Environment, Qingdao University, Qingdao 266071, China
- Corresponding author. Tel.: +86 532 83780323; fax: +86 532 85955529.
| | - X.S. Zhao
- Institute of Multifunctional Materials (IMM), Laboratory of New Fiber Materials and Modern Textile, College of Chemistry, Chemical Engineering and Environment, Qingdao University, Qingdao 266071, China
- School of Chemical Engineering, University of Queensland, St Lucia, Brisbane, QLD 4072, Australia
| |
Collapse
|
24
|
Junker K, Zandomeneghi G, Guo Z, Kissner R, Ishikawa T, Kohlbrecher J, Walde P. Mechanistic aspects of the horseradish peroxidase-catalysed polymerisation of aniline in the presence of AOT vesicles as templates. RSC Adv 2012. [DOI: 10.1039/c2ra20566a] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
|
25
|
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]
|
26
|
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
|
27
|
Electrochemical catalysis and stability of tetraamido macrocyclic ligands iron immobilized on modified pyrolytic graphite electrode. Catal Today 2010. [DOI: 10.1016/j.cattod.2010.03.046] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
|
28
|
Cheng TM, Mao SJT, Lai ST, Chang CC, Yang MC, Chen NC, Chou SC, Pan JP. Haemoglobin-induced oxidative stress is associated with both endogenous peroxidase activity and H2O2 generation from polyunsaturated fatty acids. Free Radic Res 2010; 45:303-16. [PMID: 21034361 DOI: 10.3109/10715762.2010.532492] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Patients with increased haemolytic haemoglobin (Hb) have 10-20-times greater incidence of cardiovascular mortality. The objective of this study was to evaluate the role of Hb peroxidase activity in LDL oxidation. The role of Hb in lipid peroxidation, H(2)O(2) generation and intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) was assessed using NaN(3), a peroxidase inhibitor, catalase, a H(2)O(2) decomposing enzyme and human umbilical vein endothelial cells (HUVECs), respectively. Hb induced H(2)O(2) production by reacting with LDL, linoleate and cell membrane lipid extracts. Hb-induced LDL oxidation was inhibited by NaN(3) and catalase. Furthermore, Hb stimulated ICAM-1 and VCAM-1 expression, which was inhibited by the antioxidant, probucol. Thus, the present study suggests that the peroxidase activity of Hb produces atherogenic, oxidized LDL and oxidized polyunsaturated fatty acids (PUFAs) in the cell membrane and reactive oxygen species (ROS) formation mediated Hb-induced ICAM-1 and VCAM-1 expression.
Collapse
Affiliation(s)
- Tsai-Mu Cheng
- College of Biological Science and Technology, National Chiao Tung University, Hsinchu, Taiwan, ROC
| | | | | | | | | | | | | | | |
Collapse
|
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
|
Vlasits J, Jakopitsch C, Bernroitner M, Zamocky M, Furtmüller PG, Obinger C. Mechanisms of catalase activity of heme peroxidases. Arch Biochem Biophys 2010; 500:74-81. [DOI: 10.1016/j.abb.2010.04.018] [Citation(s) in RCA: 126] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2010] [Revised: 04/23/2010] [Accepted: 04/24/2010] [Indexed: 11/15/2022]
|
31
|
Direct electrochemistry and electrocatalysis of heme-proteins immobilized in porous carbon nanofiber/room-temperature ionic liquid composite film. Electrochim Acta 2010. [DOI: 10.1016/j.electacta.2009.12.101] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
32
|
Aitken MD, Irvine RL. Stability testing of ligninase and Mn-peroxidase from Phanerochaete chrysosporium. Biotechnol Bioeng 2009; 34:1251-60. [PMID: 18588065 DOI: 10.1002/bit.260341003] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The white-rot fungus Phanerochaete chrysosporium produces extracellular peroxidases (ligninase and Mn-peroxidase) believed to be involved in lignin degradation. These extracellular enzymes have also been implicated in the degradation of recalcitrant pollutants by the organism. Commercial application of ligninase has been proposed both for biomechanical pulping of wood and for wastewater treatment. In vitro stability of lignin degrading enzymes will be an important factor in determining both the economic and technical feasibility of application for industrial uses, and also will be critical in optimizing commercial production of the enzymes. The effects of a number of variables on in vitro stability of ligninase and Mn-peroxidase are presented in this paper. Thermal stability of ligninase was found to improve by increasing pH and by increasing enzyme concentration. For a fixed pH and enzyme concentration, ligninase stability was greatly enhanced in the presence of its substrate veratryl alcohol (3,4-dimethoxybenzyl alcohol). Ligninase also was found to be inactivated by hydrogen peroxide in a second-order process that is proposed to involve the formation of the unreactive peroxidase intermediate Compound III. Mn-peroxidase was less susceptible to inactivation by peroxide, which corresponds to observations by others that Compound III of Mn-peroxidase forms less readily than Compound III of ligninase.
Collapse
Affiliation(s)
- M D Aitken
- Center for Bioengineering and Pollution Control and Department of Civil Engineering, University of Notre Dame, Notre Dame, Indiana 46556, USA
| | | |
Collapse
|
33
|
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
|
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
|
Esplandiu MJ, Pacios M, Cyganek L, Bartroli J, del Valle M. Enhancing the electrochemical response of myoglobin with carbon nanotube electrodes. NANOTECHNOLOGY 2009; 20:355502. [PMID: 19671979 DOI: 10.1088/0957-4484/20/35/355502] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
In this paper, the electrochemical behavior of different myoglobin-modified carbon electrodes is evaluated. In particular, the performance of voltammetric biosensors made of forest-like carbon nanotubes, carbon nanotube composites and graphite composites is compared by monitoring mainly the electrocatalytic reduction of H(2)O(2) by myoglobin and their corresponding electroanalytical characteristics. Graphite composites showed the worst electroanalytical performance, exhibiting a small linear range, a limit of detection (LOD) of 9 x 10(-5) M and low sensitivity. However, it was found that the electrochemical response was enhanced with the use of carbon nanotube-based electrodes with LOD up to 5 x 10(-8) M, higher sensitivities and wider linear range response. On the one hand, in the case of the CNT epoxy composite, the improvement in the response can be mainly attributed to its more porous surface which allows the immobilization of higher amounts of the electroactive protein. On the other hand, in the case of the forest-like CNT electrodes, the enhancement is due to an increase in the electron transfer kinetics. These findings encourage the use of myoglobin-modified carbon nanotube electrodes as potential (bio)sensors of H(2)O(2) or O(2) in biology, microbiology and environmental fields.
Collapse
Affiliation(s)
- M J Esplandiu
- Sensors and Biosensors Group, Department of Chemistry, Universitat Autónoma de Barcelona, Bellaterra, Barcelona, Spain.
| | | | | | | | | |
Collapse
|
36
|
Inactivation of Coprinus cinereus peroxidase during the oxidation of various phenolic compounds originated from lignin. Enzyme Microb Technol 2009. [DOI: 10.1016/j.enzmictec.2009.05.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
37
|
Liu H, Llano J, Gauld JW. A DFT study of nucleobase dealkylation by the DNA repair enzyme AlkB. J Phys Chem B 2009; 113:4887-98. [PMID: 19338370 DOI: 10.1021/jp810715t] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Oxidative dealkylation is a unique mechanistic pathway found in the alpha-ketoglutarate-Fe(II)-dependent AlkB family of enzymes to remove the alkylation damage to DNA bases and regenerate nucleobases to their native state. The B3LYP density functional combined with a self-consistent reaction field was used to explore the triplet, quintet, and septet spin-state potential energy surfaces of the multistep catalytic mechanism of AlkB. The mechanism was found to consist of four stages. First, binding of dioxygen to iron in the active-site complex occurs concerted with electron transfer, thereby yielding a ferric-superoxido species. Second, competing initiation for the activation of oxygen to generate the high-valent iron-oxygen intermediates (ferryl-oxo Fe(IV)O and ferric-oxyl Fe(III)O(*) species) was found to occur on the quintet and septet surfaces. Then, conformational reorientation of the activated iron-oxygen ligand was found to be nearly thermoneutral with a barrier of ca. 50 kJ mol(-1). The final stage is the oxidative dealkylation of the damaged nucleobase with the rate-controlling step being the abstraction of a hydrogen atom from the damaging methyl group by the ferryl-oxo ligand. For this step, the calculated barrier of 87.4 kJ mol(-1) is in good agreement with the experimental activation energy of ca. 83 kJ mol(-1) for the enzyme-catalyzed reaction.
Collapse
Affiliation(s)
- Haining Liu
- Department of Chemistry and Biochemistry, University of Windsor, Windsor, Ontario N9B 3P4, Canada
| | | | | |
Collapse
|
38
|
Kinetic analysis for suicide-substrate inactivation of microperoxidase-11: A modified model for bisubstrate enzymes in the presence of reversible inhibitors. ACTA ACUST UNITED AC 2009. [DOI: 10.1016/j.molcatb.2008.04.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
|
39
|
Khosraneh M, Mahmoudi A, Rahimi H, Nazari K, Moosavi-Movahedi AA. Suicide-Peroxide inactivation of microperoxidase-11: A kinetic study. J Enzyme Inhib Med Chem 2008; 22:677-84. [DOI: 10.1080/14756360701270683] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
|
40
|
ElKaoutit M, Naranjo-Rodriguez I, Domínguez M, Hernández-Artiga MP, Bellido-Milla D, Hidalgo-Hidalgo de Cisneros JL. A third-generation hydrogen peroxide biosensor based on Horseradish Peroxidase (HRP) enzyme immobilized in a Nafion–Sonogel–Carbon composite. Electrochim Acta 2008. [DOI: 10.1016/j.electacta.2008.04.086] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
|
41
|
Li G, Liu X, Du L, Wang E. Direct Electrochemistry of Horseradish Peroxidase Immobilized in Calcium Carbonate Microsphere Doped with Phospholipids. ELECTROANAL 2008. [DOI: 10.1002/elan.200704203] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
42
|
Soares VA, Severino D, Junqueira HC, Tersariol ILS, Shida CS, Baptista MS, Nascimento OR, Nantes IL. Light-Driven Horseradish Peroxidase Cycle by Using Photo-activated Methylene Blue as the Reducing Agent. Photochem Photobiol 2007; 83:1254-62. [PMID: 17880521 DOI: 10.1111/j.1751-1097.2007.00158.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
In this work, the regeneration of native horseradish peroxidase (HRP), following the consecutive reduction of oxo-ferryl pi-cation (compound I) and oxo-ferryl (compound II) forms, was observed by UV-visible spectrometry and electron paramagnetic resonance (EPR) in the presence of methylene (MB+), in the dark and under irradiation. In the dark, MB+ did not affect the rate of HRP compound I and II reduction, compatible with hydrogen peroxide as the solely reducing species. Under irradiation, the dye promoted a significant increase in the native HRP regeneration rate in a pH-dependent manner. Flash photolysis measurements revealed significant redshift of the MB+ triplet absorbance spectrum in the presence of native HRP. This result is compatible with the dye binding on the enzyme structure leading to the increase in the photogenerated MB* yield. In the presence of HRP compound II, the lifetime of the dye at 520 nm decreased approximately 75% relative to the presence of native HRP that suggests MB* as the heme iron photochemical reducing agent. In argon and in air-saturated media, photoactivated MB+ led to native HRP regeneration in a time- and concentration-dependent manner. The apparent rate constant for photoactivated MB+-promoted native HRP regeneration, in argon and in air-saturated medium and measured as a function of MB+ concentration, exhibited saturation that is suggestive of dye binding on the HRP structure. The dissociation constant (KMB) observed for the binding of dye to HRP was 5.4+/-0.6 microM and 0.57+/-0.05 microM in argon and air-saturated media, respectively. In argon-saturated medium, the rate of the conversion of HRP compound II to native HRP was significantly higher, k2argon=(2.1+/-0.1)x10(-2) s(-1), than that obtained in air-equilibrated medium, k2air=(0.73+/-0.02)x10(-2) s(-1). Under these conditions the efficiency of photoactivated MB(+)-promoted native HRP regeneration was determined in argon and air-equilibrated media as being, respectively: k2/KMB=3.9x10(3) and 12.8x10(3) M(-1) s(-1).
Collapse
Affiliation(s)
- Vanessa A Soares
- Centro Interdisciplinar de Investigação Bioquímica, Universidade de Mogi das Cruzes, Mogi das Cruzes, SP, Brazil
| | | | | | | | | | | | | | | |
Collapse
|
43
|
Active Iron-Oxo and Iron-Peroxo Species in Cytochromes P450 and Peroxidases; Oxo-Hydroxo Tautomerism with Water-Soluble Metalloporphyrins. STRUCTURE AND BONDING 2007. [DOI: 10.1007/3-540-46592-8_1] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
|
44
|
Ogusucu R, Rettori D, Munhoz DC, Netto LES, Augusto O. Reactions of yeast thioredoxin peroxidases I and II with hydrogen peroxide and peroxynitrite: rate constants by competitive kinetics. Free Radic Biol Med 2007; 42:326-34. [PMID: 17210445 DOI: 10.1016/j.freeradbiomed.2006.10.042] [Citation(s) in RCA: 149] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2006] [Revised: 09/28/2006] [Accepted: 10/14/2006] [Indexed: 11/16/2022]
Abstract
Peroxiredoxins are receiving increasing attention as defenders against oxidative damage and sensors of hydrogen peroxide-mediated signaling events. Likely to be critical for both functions is a rapid reaction with hydrogen peroxide, typically with second-order rate constants higher than 10(5) M(-1) s(-1). Until recently, however, the values reported for these rate constants have been in the range of 10(4)-10(5) M(-1) s(-1), including those for cytosolic thioredoxin peroxidases I (Tsa1) and II (Tsa2) from Saccharomyces cerevisiae. To resolve this apparent paradox, we developed a competitive kinetic approach with horseradish peroxidase to determine the second-order rate constant of the reaction of peroxiredoxins with peroxynitrite and hydrogen peroxide. This method was validated and allowed for the determination of the second-order rate constant of the reaction of Tsa1 and Tsa2 with peroxynitrite (k approximately 10(5) M(-1) s(-1)) and hydrogen peroxide (k approximately 10(7) M(-1) s(-1)) at pH 7.4, 25 degrees C. It also permitted the determination of the pKa of the peroxidatic cysteine of Tsa1 and Tsa2 (Cys47) as 5.4 and 6.3, respectively. In addition to providing a useful method for studying thiol protein kinetics, our studies add to recent reports challenging the popular belief that peroxiredoxins are poor enzymes toward hydrogen peroxide, as compared with heme and selenium proteins.
Collapse
Affiliation(s)
- Renata Ogusucu
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil
| | | | | | | | | |
Collapse
|
45
|
Andrieux CP, Limoges B, Savéant JM, Yazidi D. Cyclic voltammetric responses of horseradish peroxidase multilayers on electrodes. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2006; 22:10807-15. [PMID: 17129064 DOI: 10.1021/la061193s] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
The catalytic responses obtained with step-by-step neutravidin-biotin deposition of successive monolayers of HRP are analyzed by means of cyclic voltammetry. The theoretical tools that have been developed allowed full characterization of the multilayered HRP coatings by means of a combination between closed-form analysis of limiting behaviors and finite difference numerical computations. An analysis of the experiments in which the number of monolayers was extended to 16 allowed an approximate determination of the average thickness of each monolayer, pointing to a compact arrangement of neutravidin and biotinylated HRP. The piling up of so many monolayers on the electrode allowed an improvement of the catalytic current by a factor of ca. 10, leading to very good sensitivities in term of cosubstrate detection.
Collapse
Affiliation(s)
- Claude P Andrieux
- Laboratoire d'Electrochimie Moléculaire, UMR CNRS 7591, Université de Paris 7-Denis Diderot, 2 place Jussieu, 75251 Paris Cedex 05, France
| | | | | | | |
Collapse
|
46
|
Li Y, Lin X, Jiang C. Fabrication of a Nanobiocomposite Film Containing Heme Proteins and Carbon Nanotubes on a Choline Modified Glassy Carbon Electrode: Direct Electrochemistry and Electrochemical Catalysis. ELECTROANAL 2006. [DOI: 10.1002/elan.200603618] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
47
|
Ghamouss F, Ledru S, Ruillé N, Lantier F, Boujtita M. Bulk-modified modified screen-printing carbon electrodes with both lactate oxidase (LOD) and horseradish peroxide (HRP) for the determination of l-lactate in flow injection analysis mode. Anal Chim Acta 2006; 570:158-64. [PMID: 17723394 DOI: 10.1016/j.aca.2006.04.022] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2005] [Revised: 04/01/2006] [Accepted: 04/07/2006] [Indexed: 11/15/2022]
Abstract
A screen-printed carbon electrode modified with both HRP and LOD (SPCE-HRP/LOD) has been developed for the determination of L-lactate concentration in real samples. The resulting SPCE-HRP/LOD was prepared in a one-step procedure, and was then optimised as an amperometric biosensor operating at [0, -100]mV versus Ag/AgCl for L-lactate determination in flow injection mode. A significant improvement in the reproducibility (coefficient variation of about 10%) of the preparation of the biosensors was obtained when graphite powder was modified with LOD in the presence of HRP previously oxidised by periodate ion (IO4-). Optimisation studies were performed by examining the effects of LOD loading, periodation step and rate of the binder on analytical performances of SPCE-HRP/LOD. The sensitivity of the optimised SPCE-HRP/LOD to L-lactate was 0.84 nAL micromol(-1) in a detection range between 10 and 180 microMol. The possibility of using the developed biosensor to determine L-lactate concentrations in various dairy products was also evaluated.
Collapse
Affiliation(s)
- Fouad Ghamouss
- Groupe Méthodologie Electrochimique, LAIEM, UMR/CNRS 6006, FCMN, FR/CNRS 2465, Université de Nantes, Faculté des Sciences et des Techniques, 2, rue de la Houssinière, B.P. 92208, 44322 Nantes Cedex 03, France
| | | | | | | | | |
Collapse
|
48
|
Carvalho RH, Lemos F, Lemos MANDA, Vojinović V, Fonseca LP, Cabral JMS. Kinetic modelling of phenol co-oxidation using horseradish peroxidase. Bioprocess Biosyst Eng 2006; 29:99-108. [PMID: 16612606 DOI: 10.1007/s00449-006-0057-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2006] [Accepted: 03/14/2006] [Indexed: 11/25/2022]
Abstract
Phenol is an industrial pollutant and its removal from industrial wastewaters is of great importance. In order to design optimised phenol removal procedures by using horseradish peroxidase-based systems, there are some points that have to be dealt with. One of the most important issues is the need for reliable kinetics as this is one of the difficulties found during process scale-up. Although simplified kinetics can be used for limited ranges of operating conditions, they are not usually reliable for the description of varying process conditions. The present work describes the implementation of a kinetic model, based on a mechanism, for the co-oxidation of phenol and 4-aminoantipyrine (Am-NH2), which is used as a chromogen agent, with hydrogen peroxide as the oxidant. The model covers not only the variation of the concentrations of all the species involved, but also the effect of temperature in the reaction. The estimation of kinetic rate constants and activation energies for the various steps in the mechanism is performed with a single optimisation procedure, and all the experimental results are described using a unique set of parameters, which, thus, is valid over an extended range of operating conditions. The mechanism allowed the determination of a reliable kinetic model which is appropriate for the range of experimental conditions used. The computational model was also tested with an independent set of experiments with different conditions from the ones for which the parameters were estimated.
Collapse
Affiliation(s)
- R H Carvalho
- Centro de Engenharia Biológica e Química, Departmento Engenharia Química, Instituto Superior Técnico, Av. Rovisco Pais, 1049-001, Lisbon, Portugal
| | | | | | | | | | | |
Collapse
|
49
|
Terner J, Palaniappan V, Gold A, Weiss R, Fitzgerald MM, Sullivan AM, Hosten CM. Resonance Raman spectroscopy of oxoiron(IV) porphyrin π-cation radical and oxoiron(IV) hemes in peroxidase intermediates. J Inorg Biochem 2006; 100:480-501. [PMID: 16513173 DOI: 10.1016/j.jinorgbio.2006.01.008] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2005] [Accepted: 01/04/2006] [Indexed: 11/15/2022]
Abstract
The catalytic cycle intermediates of heme peroxidases, known as compounds I and II, have been of long standing interest as models for intermediates of heme proteins, such as the terminal oxidases and cytochrome P450 enzymes, and for non-heme iron enzymes as well. Reports of resonance Raman signals for compound I intermediates of the oxo-iron(IV) porphyrin pi-cation radical type have been sometimes contradictory due to complications arising from photolability, causing compound I signals to appear similar to those of compound II or other forms. However, studies of synthetic systems indicated that protein based compound I intermediates of the oxoiron(IV) porphyrin pi-cation radical type should exhibit vibrational signatures that are different from the non-radical forms. The compound I intermediates of horseradish peroxidase (HRP), and chloroperoxidase (CPO) from Caldariomyces fumago do in fact exhibit unique and characteristic vibrational spectra. The nature of the putative oxoiron(IV) bond in peroxidase intermediates has been under discussion in the recent literature, with suggestions that the Fe(IV)O unit might be better described as Fe(IV)-OH. The generally low Fe(IV)O stretching frequencies observed for proteins have been difficult to mimic in synthetic ferryl porphyrins via electron donation from trans axial ligands alone. Resonance Raman studies of iron-oxygen vibrations within protein species that are sensitive to pH, deuteration, and solvent oxygen exchange, indicate that hydrogen bonding to the oxoiron(IV) group within the protein environment contributes to substantial lowering of Fe(IV)O frequencies relative to those of synthetic model compounds.
Collapse
Affiliation(s)
- James Terner
- Department of Chemistry, Virginia Commonwealth University, Richmond, VA 23284-2006, USA.
| | | | | | | | | | | | | |
Collapse
|
50
|
Nazari K, Mahmoudi A, Shahrooz M, Khodafarin R, Moosavi-Movahedi AA. Suicide-peroxide inactivation of horseradish peroxidase in the presence of sodium n-dodecyl sulphate: a study of the enzyme deactivation kinetics. J Enzyme Inhib Med Chem 2005; 20:285-92. [PMID: 16119200 DOI: 10.1080/14756360500042846] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
In the presence of the anionic surfactant sodium n-dodecyl sulphate (SDS), horseradish peroxidase (HRP) undergoes a deactivation process. Suicide inactivation of horseradish peroxidase by hydrogen peroxide(3 mM) was monitored by the absorbance change in product formation in the catalytic reaction cycle. The progress curve of the catalytic reaction cycle was obtained at 27degrees C and phosphate buffer 2.5 mM (pH = 7.0). The corresponding kinetic parameters i.e., intact enzyme activity (alpha i); the apparent rate constant of suicide inactivation by peroxide (ki); and the apparent rate constants of enzyme deactivation by surfactant (kd) were evaluated from the obtained kinetic equations. The experimental data are accounted for by the equations used in this investigation. Addition of SDS to the reaction mixture intensified the inactivation process. The deactivation ability of denaturant could be resolved from the observed inactivation effect of the suicide substrate by applying the proposed model. The results indicate that the deactivation and the inactivation processes are independent of each other.
Collapse
Affiliation(s)
- K Nazari
- Institute of Biochemistry and Biophysics, University of Tehran, Tehran, Iran
| | | | | | | | | |
Collapse
|