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Tomášková N, Novák P, Kožár T, Petrenčáková M, Jancura D, Yassaghi G, Man P, Sedlák E. Early modification of cytochrome c by hydrogen peroxide triggers its fast degradation. Int J Biol Macromol 2021; 174:413-423. [PMID: 33529629 DOI: 10.1016/j.ijbiomac.2021.01.189] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Revised: 01/26/2021] [Accepted: 01/28/2021] [Indexed: 12/16/2022]
Abstract
Cytochrome c (cyt c), in addition to its function as an electron shuttle in respiratory chain, is able to perform as a pseudo-peroxidase with a critical role during apoptosis. Incubation of cyt c with an excess of hydrogen peroxide leads to a suicide inactivation of the protein, which is accompanied by heme destruction and covalent modification of numerous amino acid residues. Although steady-state reactions of cyt c with an excess of hydrogen peroxide represent non-physiological conditions, they might be used for analysis of the first-modified amino acid in in vivo. Here, we observed oxidation of tyrosine residues 67 and 74 and heme as the first modifications found upon incubation with hydrogen peroxide. The positions of the oxidized tyrosines suggest a possible migration pathway of hydrogen peroxide-induced radicals from the site of heme localization to the protein surface. Analysis of a size of folded fraction of cyt c upon limited incubation with hydrogen peroxide indicates that the early oxidation of amino acids triggers an accelerated destruction of cyt c. Position of channels from molecular dynamics simulation structures of cyt c points to a location of amino acid residues exposed to reactive oxidants that are thus more prone to covalent modification.
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Affiliation(s)
- Nataša Tomášková
- Department of Biochemistry, Faculty of Science, P.J. Šafárik University, Moyzesova 11, 041 54 Košice, Slovakia
| | - Petr Novák
- Institute of Microbiology - BioCeV, Vídeňská 1083, 142 20 Prague 4, Czech Republic
| | - Tibor Kožár
- Center for Interdisciplinary Biosciences, Technology and Innovation Park, P.J. Šafárik University, Jesenná 5, 041 54 Košice, Slovakia
| | - Martina Petrenčáková
- Center for Interdisciplinary Biosciences, Technology and Innovation Park, P.J. Šafárik University, Jesenná 5, 041 54 Košice, Slovakia
| | - Daniel Jancura
- Department of Biophysics, Faculty of Science, P.J. Šafárik University, Jesenná 5, 041 54 Košice, Slovakia
| | - Ghazaleh Yassaghi
- Institute of Microbiology - BioCeV, Vídeňská 1083, 142 20 Prague 4, Czech Republic
| | - Petr Man
- Institute of Microbiology - BioCeV, Vídeňská 1083, 142 20 Prague 4, Czech Republic.
| | - Erik Sedlák
- Department of Biochemistry, Faculty of Science, P.J. Šafárik University, Moyzesova 11, 041 54 Košice, Slovakia; Center for Interdisciplinary Biosciences, Technology and Innovation Park, P.J. Šafárik University, Jesenná 5, 041 54 Košice, Slovakia.
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2
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Yin V, Holzscherer D, Konermann L. Delineating Heme-Mediated versus Direct Protein Oxidation in Peroxidase-Activated Cytochrome c by Top-Down Mass Spectrometry. Biochemistry 2020; 59:4108-4117. [PMID: 32991149 DOI: 10.1021/acs.biochem.0c00609] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Oxidation of key residues in cytochrome c (cyt c) by chloramine T (CT) converts the protein from an electron transporter to a peroxidase. This peroxidase-activated state represents an important model system for exploring the early steps of apoptosis. CT-induced transformations include oxidation of the distal heme ligand Met80 (MetO, +16 Da) and carbonylation (LysCHO, -1 Da) in the range of Lys53/55/72/73. Remarkably, the 15 remaining Lys residues in cyt c are not susceptible to carbonylation. The cause of this unusual selectivity is unknown. Here we applied top-down mass spectrometry (MS) to examine whether CT-induced oxidation is catalyzed by heme. To this end, we compared the behavior of cyt c with (holo-cyt c) and without heme (apoSS-cyt c). CT caused MetO formation at Met80 for both holo- and apoSS-cyt c, implying that this transformation can proceed independently of heme. The aldehyde-specific label Girard's reagent T (GRT) reacted with oxidized holo-cyt c, consistent with the presence of several LysCHO. In contrast, oxidized apo-cyt c did not react with GRT, revealing that LysCHO forms only in the presence of heme. The heme dependence of LysCHO formation was further confirmed using microperoxidase-11 (MP11). CT exposure of apoSS-cyt c in the presence of MP11 caused extensive nonselective LysCHO formation. Our results imply that the selectivity of LysCHO formation at Lys53/55/72/73 in holo-cyt c is caused by the spatial proximity of these sites to the reactive (distal) heme face. Overall, this work highlights the utility of top-down MS for unravelling complex oxidative modifications.
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Affiliation(s)
- Victor Yin
- Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5B7, Canada
| | - Derek Holzscherer
- Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5B7, Canada
| | - Lars Konermann
- Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5B7, Canada
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3
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Liew FN, Brandys MA, Biswas S, Nguyen JN, Rahmawati M, Nevala M, Elmore BO, Hendrich MP, Kim HJ. Cytochrome c' β-Met Is a Variant in the P460 Superfamily Lacking the Heme-Lysyl Cross-Link: A Peroxidase Mimic Generating a Ferryl Intermediate. Biochemistry 2020; 59:704-716. [PMID: 31887031 DOI: 10.1021/acs.biochem.9b00810] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A defining characteristic of bacterial cytochromes (cyt's) in the P460 family is an unusual cross-link connecting the heme porphyrin to the side chain of a lysyl residue in the protein backbone. Here, via proteomics of the periplasmic fraction of the ammonia-oxidizing bacterium (AOB) Nitrosomonas europaea, we report the identification of a variant member of the P460 family that contains a methionyl residue in place of the cross-linking lysine. We formally designate this protein cytochrome "c'β-Met" to distinguish it from other members bearing different residues at this position (e.g., cyt c'β-Phe from the methane-oxidizing Methylococcus capsulatus Bath). As isolated, the monoheme cyt c'β-Met is high-spin (S = 5/2). Optical spectroscopy suggests that a cross-link is absent. Hydroxylamine, the substrate for the cross-linked cyt P460 from N. europaea, did not appreciably alter the optical spectrum of cyt c'β with up to 1000-fold excess at pH 7.5. Cyt c'β-Met did however bind 1 equiv of H2O2, and with a slight excess, Mössbauer spectroscopy indicated the formation of a semistable ferryl (FeIV═O) Compound II-like species. The corresponding electron paramagnetic resonance showed a very low intensity signal indicative of a radical at g = 2.0. Furthermore, cyt c'β-Met exhibited guaiacol-dependent peroxidase activity (kcat = 20.0 ± 1.2 s-1; KM = 2.6 ± 0.4 mM). Unlike cyt c'β-Met, cyt P460 showed evidence of heme inactivation in the presence of 2 equiv of H2O2 with no appreciable guaiacol-dependent peroxidase activity. Mutagenesis of the cross-linking lysyl residue to an alanine in cyt P460, however, reversed this lack of activity.
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Affiliation(s)
- Fong Ning Liew
- Division of Physical Sciences, Chemistry , University of Washington Bothell , Bothell , Washington 98012 , United States
| | - Marisa A Brandys
- Division of Physical Sciences, Chemistry , University of Washington Bothell , Bothell , Washington 98012 , United States
| | - Saborni Biswas
- Department of Chemistry , Carnegie Mellon University , Pittsburgh , Pennsylvania 15213 , United States
| | - Joline N Nguyen
- Division of Physical Sciences, Chemistry , University of Washington Bothell , Bothell , Washington 98012 , United States
| | - Mustika Rahmawati
- Division of Physical Sciences, Chemistry , University of Washington Bothell , Bothell , Washington 98012 , United States
| | - Michael Nevala
- Division of Physical Sciences, Chemistry , University of Washington Bothell , Bothell , Washington 98012 , United States.,Veolia Nuclear Solutions Federal Solutions , Richland , Washington 99354 , United States
| | - Bradley O Elmore
- Newport Laboratories , Worthington , Minnesota 56187 , United States
| | - Michael P Hendrich
- Department of Chemistry , Carnegie Mellon University , Pittsburgh , Pennsylvania 15213 , United States
| | - Hyung J Kim
- Division of Physical Sciences, Chemistry , University of Washington Bothell , Bothell , Washington 98012 , United States
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4
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Schmitt G, Birke J, Jendrossek D. Towards the understanding of the enzymatic cleavage of polyisoprene by the dihaem-dioxygenase RoxA. AMB Express 2019; 9:166. [PMID: 31624946 PMCID: PMC6797691 DOI: 10.1186/s13568-019-0888-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2019] [Accepted: 09/28/2019] [Indexed: 12/27/2022] Open
Abstract
Utilization of polyisoprene (natural rubber) as a carbon source by Steroidobacter cummioxidans 35Y (previously Xanthomonas sp. strain 35Y) depends on the formation and secretion of rubber oxygenase A (RoxA). RoxA is a dioxygenase that cleaves polyisoprene to 12-oxo-4,8-dimethyl-trideca-4,8-diene-1-al (ODTD), a suitable growth substrate for S. cummioxidans. RoxA harbours two non-equivalent, spectroscopically distinguishable haem centres. A dioxygen molecule is bound to the N-terminal haem of RoxA and identifies this haem as the active site. In this study, we provide insights into the nature of this unusually stable dioxygen-haem coordination of RoxA by a re-evaluation of previously published together with newly obtained biophysical data on the cleavage of polyisoprene by RoxA. In combination with the meanwhile available structure of RoxA we are now able to explain several uncommon and previously not fully understood features of RoxA, the prototype of rubber oxygenases in Gram-negative rubber-degrading bacteria.
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Affiliation(s)
- Georg Schmitt
- Institute of Microbiology, University of Stuttgart, Allmandring 31, 70569, Stuttgart, Germany
| | - Jakob Birke
- Institute of Microbiology, University of Stuttgart, Allmandring 31, 70569, Stuttgart, Germany
- Institute of Applied Biotechnology, University of Applied Sciences Biberach, Hubertus-Liebrecht-Strasse 35, 88400, Biberach, Germany
| | - Dieter Jendrossek
- Institute of Microbiology, University of Stuttgart, Allmandring 31, 70569, Stuttgart, Germany.
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5
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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.
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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
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6
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Plieth C. Redox Modulators Determine Luminol Luminescence Generated by Porphyrin-Coordinated Iron and May Repress "Suicide Inactivation". ACS OMEGA 2018; 3:12295-12303. [PMID: 31459303 PMCID: PMC6645248 DOI: 10.1021/acsomega.8b01261] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Accepted: 08/14/2018] [Indexed: 05/29/2023]
Abstract
Iron porphyrin catalysts of the luminol reaction (horseradish peroxidase, hemoglobin, cytochrome c, and hemin) interact with diverse reducing compounds. Here, it is demonstrated how the chemiluminescence yield is modulated by such interactions. The compounds accepted as substrates protect the catalyst against the "suicide inactivation" caused by high peroxide concentrations. The reducing agents not accepted by the catalyst inhibit light production either by generating a futile redox cycle of the luminophore or by irreversibly inactivating the catalytic center. In the case of a futile cycle, light emission resumes as soon as the reducing agents in the reaction are consumed, whereas with an irreversible inactivation, light emission does not recover. The characteristics of luminescence enhancement and quenching depending on interfering agents are also reported here. They reveal details about the relative redox potentials of the involved compounds. It is discussed how this should be considered when the luminol reaction is used for quantitative analyses and when unpurified samples with a broad compound matrix are to be assayed.
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7
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Gubitosa J, Rizzi V, Lopedota A, Fini P, Laurenzana A, Fibbi G, Fanelli F, Petrella A, Laquintana V, Denora N, Comparelli R, Cosma P. One pot environmental friendly synthesis of gold nanoparticles using Punica Granatum Juice: A novel antioxidant agent for future dermatological and cosmetic applications. J Colloid Interface Sci 2018; 521:50-61. [PMID: 29549765 DOI: 10.1016/j.jcis.2018.02.069] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Revised: 02/22/2018] [Accepted: 02/23/2018] [Indexed: 01/09/2023]
Abstract
HYPOTHESIS The interesting properties of Gold Nanoparticles (AuNPs) make them attractive for different application fields such as cosmetology, medicine and clinical nanotechnologies. In this work a fast, easy and eco-friendly method for the AuNPs synthesis is proposed by using the Punica Granatum Juice (PGJ) with potential dermatological and cosmetic applications. The AuNPs antioxidant activity, due to the presence of phenols from the juice, and their use as booster for improving the Sun Protection Factor (SPF) in commercial sunscreen formulations, are thus expounded. EXPERIMENTS By using appropriate amounts of PGJ and HAuCl4, under mild work conditions, AuNPs with a mean size of 100 ± 40 nm are observed and carefully characterized. Solution pH, temperature, and volume were also changed for optimizing the AuNPs formation and features. The antioxidant activity was studied, by evaluating the AuNP ability of scavenging the radical 2,2-diphenyl-1-picrylhydrazylhydrate (DPPH). This finding was confirmed performing special experiments focused on the reaction between AuNPs and H2O2, by using suitable probes, such as 4-thiothymidine (S4TdR) and Cytochrome-c (Cyt-c). The SPF value was also calculated. FINDINGS The synthetized AuNPs showed a surface plasmon in visible range at 577 nm and resulted stable for long time in aqueous medium, also changing the pH values in the range 2-12. The studied antioxidant activity, confirmed also by performing special experiments with suitable probes, demonstrated the high performance of AuNPs. The AuNP photostability under sun irradiation is also shown. The calculated SPF values were in the range 3-18, related to AuNPs concentration in the range 1.80 × 10-12-1.00 × 10-11 M. The same AuNPs concentrations were used for cellular experiments. Indeed, since the AuNPs-PGJ mediated will be potentially introduced by dermal contact, dermal fibroblasts (Human Dermal Fibroblasts, HDF) and Human Microvascular Endothelial Cells (HMVEC) were used to evaluate the possible effects of these nanoparticles as a preliminary step. The results indicated that an AuNP concentrations in the range 1.80 × 10-12-3.60 × 10-12 M could be adopted since they do not appeared cyctotoxic.
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Affiliation(s)
- Jennifer Gubitosa
- Dipartimento di Farmacia-Scienze del Farmaco - Unità di Tecnologia farmaceutica, Università degli Studi di Bari "A. Moro", Via Orabona, 4, 70125 Bari, Italy
| | - Vito Rizzi
- Università degli Studi "Aldo Moro" di Bari, Dip. Chimica, Via Orabona, 4, 70126 Bari, Italy
| | - Angela Lopedota
- Dipartimento di Farmacia-Scienze del Farmaco - Unità di Tecnologia farmaceutica, Università degli Studi di Bari "A. Moro", Via Orabona, 4, 70125 Bari, Italy
| | - Paola Fini
- Consiglio Nazionale delle Ricerche CNR-IPCF, UOS Bari, Via Orabona, 4, 70126 Bari, Italy
| | - Anna Laurenzana
- Dipartimento di Scienze Biomediche Sperimentali e Cliniche "MarioSerio", Viale Morgagni 50 - 50134, Florence, Italy
| | - Gabriella Fibbi
- Dipartimento di Scienze Biomediche Sperimentali e Cliniche "MarioSerio", Viale Morgagni 50 - 50134, Florence, Italy
| | - Fiorenza Fanelli
- Consiglio Nazionale delle Ricerche, Istituto di Nanotecnologia (CNR-NANOTEC) c/o Dipartimento di Chimica, Università degli Studi "Aldo Moro", Via Orabona, 4, 70126 Bari, Italy
| | - Andrea Petrella
- Dipartimento di Ingegneria Civile, Ambientale, Edile, del Territorio e di Chimica, Politecnico di Bari, Orabona, 4, 70125 Bari, Italy
| | - Valentino Laquintana
- Dipartimento di Farmacia-Scienze del Farmaco - Unità di Tecnologia farmaceutica, Università degli Studi di Bari "A. Moro", Via Orabona, 4, 70125 Bari, Italy
| | - Nunzio Denora
- Dipartimento di Farmacia-Scienze del Farmaco - Unità di Tecnologia farmaceutica, Università degli Studi di Bari "A. Moro", Via Orabona, 4, 70125 Bari, Italy
| | - Roberto Comparelli
- Consiglio Nazionale delle Ricerche CNR-IPCF, UOS Bari, Via Orabona, 4, 70126 Bari, Italy
| | - Pinalysa Cosma
- Università degli Studi "Aldo Moro" di Bari, Dip. Chimica, Via Orabona, 4, 70126 Bari, Italy; Consiglio Nazionale delle Ricerche CNR-IPCF, UOS Bari, Via Orabona, 4, 70126 Bari, Italy.
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8
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Zygouri P, Tsoufis T, Kouloumpis A, Patila M, Potsi G, Sevastos AA, Sideratou Z, Katsaros F, Charalambopoulou G, Stamatis H, Rudolf P, Steriotis TA, Gournis D. Synthesis, characterization and assessment of hydrophilic oxidized carbon nanodiscs in bio-related applications. RSC Adv 2018. [DOI: 10.1039/c7ra11045f] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Hydrophilic oxidized carbon nanodiscs able to be used as drug delivery system and as support in nanobiocatalytic applications.
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9
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Yin V, Shaw GS, Konermann L. Cytochrome c as a Peroxidase: Activation of the Precatalytic Native State by H2O2-Induced Covalent Modifications. J Am Chem Soc 2017; 139:15701-15709. [DOI: 10.1021/jacs.7b07106] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- Victor Yin
- Department of Chemistry and Department
of Biochemistry, The University of Western Ontario, London, Ontario N6A 5B7, Canada
| | - Gary S. Shaw
- Department of Chemistry and Department
of Biochemistry, The University of Western Ontario, London, Ontario N6A 5B7, Canada
| | - Lars Konermann
- Department of Chemistry and Department
of Biochemistry, The University of Western Ontario, London, Ontario N6A 5B7, Canada
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10
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Zhou P, Lan D, Popowicz GM, Wang X, Yang B, Wang Y. Enhancing H2O2 resistance of an esterase from Pyrobaculum calidifontis by structure-guided engineering of the substrate binding site. Appl Microbiol Biotechnol 2017; 101:5689-5697. [DOI: 10.1007/s00253-017-8299-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Revised: 04/06/2017] [Accepted: 04/12/2017] [Indexed: 11/28/2022]
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11
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Ciaccio C, Tognaccini L, Battista T, Cervelli M, Howes BD, Santucci R, Coletta M, Mariottini P, Smulevich G, Fiorucci L. The Met80Ala and Tyr67His/Met80Ala mutants of human cytochrome c shed light on the reciprocal role of Met80 and Tyr67 in regulating ligand access into the heme pocket. J Inorg Biochem 2017; 169:86-96. [DOI: 10.1016/j.jinorgbio.2017.01.008] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2016] [Revised: 01/13/2017] [Accepted: 01/20/2017] [Indexed: 10/20/2022]
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12
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Bisht M, Venkatesu P. Influence of cholinium-based ionic liquids on the structural stability and activity of α-chymotrypsin. NEW J CHEM 2017. [DOI: 10.1039/c7nj03023a] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Unanticipated high thermal stability and sustained activity of CT was found in the presence of [Ch][Ac], [Ch][Cl] and [Ch][Dhp], while [Ch][Cit] and [Ch][OH] act as strong destabilizers for the CT structure.
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Affiliation(s)
- Meena Bisht
- Department of Chemistry, University of Delhi
- Delhi-110 007
- India
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13
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Caruso CS, Biazin E, Carvalho FA, Tabak M, Bachega JF. Metals content of Glossoscolex paulistus extracellular hemoglobin: Its peroxidase activity and the importance of these ions in the protein stability. J Inorg Biochem 2016; 161:63-72. [DOI: 10.1016/j.jinorgbio.2016.05.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Revised: 04/08/2016] [Accepted: 05/04/2016] [Indexed: 10/21/2022]
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14
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Abstract
An artificial peroxidase with thermal tolerance and high catalytic activity has been successfully prepared by mutagenesis of an electron transfer protein, cytochrome c552 from Thermus thermophilus. The mutant enzymes were rationally designed based on the general peroxidase mechanism and spectroscopic analyses of an active intermediate formed in the catalytic reaction. Stopped flow UV-vis spectroscopy and EPR spectroscopy with a rapid freezing sample technique revealed that the initial double mutant, V49D/M69A, which was designed to reproduce the peroxidase mechanism, formed an active oxo-ferryl heme intermediate with a protein radical predominantly localized on Tyr45 during the catalytic reaction. The magnetic power saturation measurement obtained from EPR studies showed little interaction between the oxo-ferryl heme and the tyrosyl radical. Kinetics studies indicated that the isolated oxo-ferryl heme component in the active intermediate was a possible cause of heme degradation during the reaction with H2O2. Strong interaction between the oxo-ferryl heme and the radical was achieved by replacing Tyr45 with tryptophan (resulting in the Y45W/V49D/M69A mutant), which was similar to a tryptophanyl radical found in active intermediates of some catalase-peroxidases. Compared to the protein radical intermediates of V49D/M69A mutant, those of the Y45W/V49D/M69A mutant showed higher reactivity to an organic substrate than to H2O2. The Y45W/V49D/M69A mutant exhibited improved peroxidase activity and thermal tolerance.
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Affiliation(s)
- Y Watanabe
- Research Center of Materials Science, Nagoya University, Nagoya, Japan
| | - H Nakajima
- Graduate School of Science, Osaka City University, Osaka, Japan.
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15
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Graphene oxide derivatives with variable alkyl chain length and terminal functional groups as supports for stabilization of cytochrome c. Int J Biol Macromol 2016; 84:227-35. [DOI: 10.1016/j.ijbiomac.2015.12.023] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Revised: 12/08/2015] [Accepted: 12/10/2015] [Indexed: 11/20/2022]
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16
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Husband J, Aaron MS, Bains RK, Lewis AR, Warren JJ. Catalytic reduction of dioxygen with modified Thermus thermophilus cytochrome c552. J Inorg Biochem 2016; 157:8-14. [PMID: 26816109 DOI: 10.1016/j.jinorgbio.2016.01.023] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Revised: 12/23/2015] [Accepted: 01/18/2016] [Indexed: 10/22/2022]
Abstract
Efficient catalysis of the oxygen reduction reaction (ORR) is of central importance to function in fuel cells. Metalloproteins, such as laccase (Cu) or cytochrome c oxidase (Cu/Fe-heme) carry out the 4H(+)/4e(-) reduction quite efficiently, but using large, complex protein frameworks. Smaller heme proteins also can carry out ORR, but less efficiently. To gain greater insight into features that promote efficient ORR, we expressed, characterized, and investigated the electrochemical behavior of six new mutants of cytochrome c552 from Thermus thermophilus: V49S/M69A, V49T/M69A, L29D/V49S/M69A, P27A/P28A/L29D/V49S/M69A, and P27A/P28A/L29D/V49T/M69A. Mutation to V49 causes only minor shifts to Fe(III/II) reduction potentials (E°'), but introduction of Ser provides a hydrogen bond donor that slightly enhances oxygen reduction activity. Mutation of L29 to D induces small shifts in heme optical spectra, but not to E°' (within experimental error). Replacement of P27 and P28 with A in both positions induces a -50 mV shift in E°', again with small changes to the optical spectra. Both the optical spectra and reduction potentials have signatures consistent with peroxidase enzymes. The V49S and V49T mutations have the largest impact of ORR catalysis, suggesting that increased electron density at the Fe site does not improve O2 reduction chemistry.
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Affiliation(s)
- Jonathan Husband
- Department of Chemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada
| | - Michael S Aaron
- Department of Chemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada
| | - Rajneesh K Bains
- Department of Chemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada
| | - Andrew R Lewis
- Department of Chemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada
| | - Jeffrey J Warren
- Department of Chemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada.
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17
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Tognaccini L, Ciaccio C, D'Oria V, Cervelli M, Howes BD, Coletta M, Mariottini P, Smulevich G, Fiorucci L. Structure-function relationships in human cytochrome c: The role of tyrosine 67. J Inorg Biochem 2015; 155:56-66. [PMID: 26610191 DOI: 10.1016/j.jinorgbio.2015.11.011] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Revised: 11/03/2015] [Accepted: 11/10/2015] [Indexed: 11/20/2022]
Abstract
Spectroscopic and functional properties of human cytochrome c and its Tyr67 residue mutants (i.e., Tyr67His and Tyr67Arg) have been investigated. In the case of the Tyr67His mutant, we have observed only a very limited structural alteration of the heme pocket and of the Ω-loop involving, among others, the residue Met80 and its bond with the heme iron. Conversely, in the Tyr67Arg mutant the Fe-Met80 bond is cleaved; consequently, a much more extensive structural alteration of the Ω-loop can be envisaged. The structural, and thus the functional modifications, of the Tyr67Arg mutant are present in both the ferric [Fe(III)] and the ferrous [Fe(II)] forms, indicating that the structural changes are independent of the heme iron oxidation state, depending instead on the type of substituting residue. Furthermore, a significant peroxidase activity is evident for the Tyr67Arg mutant, highlighting the role of Arg as a basic, positively charged residue at pH7.0, located in the heme distal pocket, which may act as an acid to cleave the O-O bond in H2O2. As a whole, our results indicate that a delicate equilibrium is associated with the spatial arrangement of the Ω-loop. Clearly, Arg, but not His, is able to stabilize and polarize the negative charge on the Fe(III)-OOH complex during the formation of Compound I, with important consequences on cytochrome peroxidation activity and its role in the apoptotic process, which is somewhat different in yeast and mammals.
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Affiliation(s)
- Lorenzo Tognaccini
- Department of Chemistry "Ugo Schiff", University of Florence, Sesto Fiorentino, FI, Italy
| | - Chiara Ciaccio
- Department of Clinical Sciences and Translational Medicine, University of Rome Tor Vergata, Rome, Italy; Interuniversity Consortium for the Research on the Chemistry of Metals in Biological Systems (CIRCMSB), Bari, Italy
| | - Valentina D'Oria
- Department of Clinical Sciences and Translational Medicine, University of Rome Tor Vergata, Rome, Italy
| | | | - Barry D Howes
- Department of Chemistry "Ugo Schiff", University of Florence, Sesto Fiorentino, FI, Italy
| | - Massimo Coletta
- Department of Clinical Sciences and Translational Medicine, University of Rome Tor Vergata, Rome, Italy; Interuniversity Consortium for the Research on the Chemistry of Metals in Biological Systems (CIRCMSB), Bari, Italy
| | | | - Giulietta Smulevich
- Department of Chemistry "Ugo Schiff", University of Florence, Sesto Fiorentino, FI, Italy; Interuniversity Consortium for the Research on the Chemistry of Metals in Biological Systems (CIRCMSB), Bari, Italy.
| | - Laura Fiorucci
- Department of Clinical Sciences and Translational Medicine, University of Rome Tor Vergata, Rome, Italy.
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Sáez-Jiménez V, Acebes S, Guallar V, Martínez AT, Ruiz-Dueñas FJ. Improving the oxidative stability of a high redox potential fungal peroxidase by rational design. PLoS One 2015; 10:e0124750. [PMID: 25923713 PMCID: PMC4414599 DOI: 10.1371/journal.pone.0124750] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2015] [Accepted: 03/05/2015] [Indexed: 11/19/2022] Open
Abstract
Ligninolytic peroxidases are enzymes of biotechnological interest due to their ability to oxidize high redox potential aromatic compounds, including the recalcitrant lignin polymer. However, different obstacles prevent their use in industrial and environmental applications, including low stability towards their natural oxidizing-substrate H2O2. In this work, versatile peroxidase was taken as a model ligninolytic peroxidase, its oxidative inactivation by H2O2 was studied and different strategies were evaluated with the aim of improving H2O2 stability. Oxidation of the methionine residues was produced during enzyme inactivation by H2O2 excess. Substitution of these residues, located near the heme cofactor and the catalytic tryptophan, rendered a variant with a 7.8-fold decreased oxidative inactivation rate. A second strategy consisted in mutating two residues (Thr45 and Ile103) near the catalytic distal histidine with the aim of modifying the reactivity of the enzyme with H2O2. The T45A/I103T variant showed a 2.9-fold slower reaction rate with H2O2 and 2.8-fold enhanced oxidative stability. Finally, both strategies were combined in the T45A/I103T/M152F/M262F/M265L variant, whose stability in the presence of H2O2 was improved 11.7-fold. This variant showed an increased half-life, over 30 min compared with 3.4 min of the native enzyme, under an excess of 2000 equivalents of H2O2. Interestingly, the stability improvement achieved was related with slower formation, subsequent stabilization and slower bleaching of the enzyme Compound III, a peroxidase intermediate that is not part of the catalytic cycle and leads to the inactivation of the enzyme.
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Affiliation(s)
- Verónica Sáez-Jiménez
- Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Sandra Acebes
- Joint Barcelona Supercomputing Center—Centre for Genomic Regulation, Institute for Research in Biomedicine Research Program in Computational Biology, Barcelona Supercomputing Center, Barcelona, Spain
| | - Victor Guallar
- Joint Barcelona Supercomputing Center—Centre for Genomic Regulation, Institute for Research in Biomedicine Research Program in Computational Biology, Barcelona Supercomputing Center, Barcelona, Spain
| | - Angel T. Martínez
- Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Francisco J. Ruiz-Dueñas
- Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas, Madrid, Spain
- * E-mail:
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Structural basis for cytochrome c Y67H mutant to function as a peroxidase. PLoS One 2014; 9:e107305. [PMID: 25210769 PMCID: PMC4161393 DOI: 10.1371/journal.pone.0107305] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2013] [Accepted: 08/14/2014] [Indexed: 11/23/2022] Open
Abstract
The catalytic activity of cytochrome c (cyt c) to peroxidize cardiolipin to its oxidized form is required for the release of pro-apoptotic factors from mitochondria, and for execution of the subsequent apoptotic steps. However, the structural basis for this peroxidation reaction remains unclear. In this paper, we determined the three-dimensional NMR solution structure of yeast cyt c Y67H variant with high peroxidase activity, which is almost similar to that of its native form. The structure reveals that the hydrogen bond between Met80 and residue 67 is disrupted. This change destabilizes the sixth coordination bond between heme Fe3+ ion and Met80 sulfur atom in the Y67H variant, and further makes it more easily be broken at low pH conditions. The steady-state studies indicate that the Y67H variant has the highest peroxidase activities when pH condition is between 4.0 and 5.2. Finally, a mechanism is suggested for the peroxidation of cardiolipin catalyzed by the Y67H variant, where the residue His67 acts as a distal histidine, its protonation facilitates O-O bond cleavage of H2O2 by functioning as an acidic catalyst.
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Delgado Y, Morales-Cruz M, Hernández-Román J, Martínez Y, Griebenow K. Chemical glycosylation of cytochrome c improves physical and chemical protein stability. BMC BIOCHEMISTRY 2014; 15:16. [PMID: 25095792 PMCID: PMC4137108 DOI: 10.1186/1471-2091-15-16] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/17/2014] [Accepted: 08/01/2014] [Indexed: 11/14/2022]
Abstract
Background Cytochrome c (Cyt c) is an apoptosis-initiating protein when released into the cytoplasm of eukaryotic cells and therefore a possible cancer drug candidate. Although proteins have been increasingly important as pharmaceutical agents, their chemical and physical instability during production, storage, and delivery remains a problem. Chemical glycosylation has been devised as a method to increase protein stability and thus enhance their long-lasting bioavailability. Results Three different molecular weight glycans (lactose and two dextrans with 1 kD and 10 kD) were chemically coupled to surface exposed Cyt c lysine (Lys) residues using succinimidyl chemistry via amide bonds. Five neo-glycoconjugates were synthesized, Lac4-Cyt-c, Lac9-Cyt-c, Dex5(10kD)-Cyt-c, Dex8(10kD)-Cyt-c, and Dex3(1kD)-Cyt-c. Subsequently, we investigated glycoconjugate structure, activity, and stability. Circular dichroism (CD) spectra demonstrated that Cyt c glycosylation did not cause significant changes to the secondary structure, while high glycosylation levels caused some minor tertiary structure perturbations. Functionality of the Cyt c glycoconjugates was determined by performing cell-free caspase 3 and caspase 9 induction assays and by measuring the peroxidase-like pseudo enzyme activity. The glycoconjugates showed ≥94% residual enzyme activity and 86 ± 3 to 95 ± 1% relative caspase 3 activation compared to non-modified Cyt c. Caspase 9 activation by the glycoconjugates was with 92 ± 7% to 96 ± 4% within the error the same as the caspase 3 activation. There were no major changes in Cyt c activity upon glycosylation. Incubation of Dex3(1 kD)-Cyt c with mercaptoethanol caused significant loss in the tertiary structure and a drop in caspase 3 and 9 activation to only 24 ± 8% and 26 ± 6%, respectively. This demonstrates that tertiary structure intactness of Cyt c was essential for apoptosis induction. Furthermore, glycosylation protected Cyt c from detrimental effects by some stresses (i.e., elevated temperature and humidity) and from proteolytic degradation. In addition, non-modified Cyt c was more susceptible to denaturation by a water-organic solvent interface than its glycoconjugates, important for the formulation in polymers. Conclusion The results demonstrate that chemical glycosylation is a potentially valuable method to increase Cyt c stability during formulation and storage and potentially during its application after administration.
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Affiliation(s)
| | | | | | | | - Kai Griebenow
- Department of Biology, University of Puerto Rico, Río Piedras Campus, P,O, Box 70377, San Juan, Puerto Rico 00931-3346, USA.
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Evolutionary potential, cross-stress behavior and the genetic basis of acquired stress resistance in Escherichia coli. Mol Syst Biol 2013; 9:643. [PMID: 23385483 PMCID: PMC3588905 DOI: 10.1038/msb.2012.76] [Citation(s) in RCA: 100] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2012] [Accepted: 12/08/2012] [Indexed: 12/20/2022] Open
Abstract
Escherichia coli cells were evolved over 500 generations and profiled in four abiotic stressors to observe several cases of emerging cross-stress behavior whereby adaptation to one stressful environment provided fitness advantage when exposed to a second stressor. ![]()
Cross-stress dependencies were found to be ubiquitous, highly interconnected and can emerge within short timeframes. Several targets were implicated in adaptation and cross-stress protection, including genes related to iron transport and flagella. Adaptation in a first stress can lead to higher fitness to a second stress when compared with cells adapted only in the latter environment. Adaptation to any specific stress and the growth media was found to be generally independent.
Bacterial populations have a remarkable capacity to cope with extreme environmental fluctuations in their natural environments. In certain cases, adaptation to one stressful environment provides a fitness advantage when cells are exposed to a second stressor, a phenomenon that has been coined as cross-stress protection. A tantalizing question in bacterial physiology is how the cross-stress behavior emerges during evolutionary adaptation and what the genetic basis of acquired stress resistance is. To address these questions, we evolved Escherichia coli cells over 500 generations in five environments that include four abiotic stressors. Through growth profiling and competition assays, we identified several cases of positive and negative cross-stress behavior that span all strain–stress combinations. Resequencing the genomes of the evolved strains resulted in the identification of several mutations and gene amplifications, whose fitness effect was further assessed by mutation reversal and competition assays. Transcriptional profiling of all strains under a specific stress, NaCl-induced osmotic stress, and integration with resequencing data further elucidated the regulatory responses and genes that are involved in this phenomenon. Our results suggest that cross-stress dependencies are ubiquitous, highly interconnected, and can emerge within short timeframes. The high adaptive potential that we observed argues that bacterial populations occupy a genotypic space that enables a high phenotypic plasticity during adaptation in fluctuating environments.
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Patila M, Pavlidis IV, Diamanti EK, Katapodis P, Gournis D, Stamatis H. Enhancement of cytochrome c catalytic behaviour by affecting the heme environment using functionalized carbon-based nanomaterials. Process Biochem 2013. [DOI: 10.1016/j.procbio.2013.04.021] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Sicking W, Somnitz H, Schmuck C. DFT Calculations Suggest a New Type of Self-Protection and Self-Inhibition Mechanism in the Mammalian Heme Enzyme Myeloperoxidase: Nucleophilic Addition of a Functional Water rather than One-Electron Reduction. Chemistry 2012; 18:10937-48. [DOI: 10.1002/chem.201103477] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2011] [Revised: 05/14/2012] [Indexed: 11/09/2022]
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Rajagopal BS, Silkstone GG, Nicholls P, Wilson MT, Worrall JA. An investigation into a cardiolipin acyl chain insertion site in cytochrome c. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2012; 1817:780-91. [DOI: 10.1016/j.bbabio.2012.02.010] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2011] [Revised: 02/03/2012] [Accepted: 02/07/2012] [Indexed: 12/18/2022]
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Águila S, Vazquez-Duhalt R, Covarrubias C, Pecchi G, Alderete JB. Enhancing oxidation activity and stability of iso-1-cytochrome c and chloroperoxidase by immobilization in nanostructured supports. ACTA ACUST UNITED AC 2011. [DOI: 10.1016/j.molcatb.2011.02.008] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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26
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Wang Z, Matsuo T, Nagao S, Hirota S. Peroxidase activity enhancement of horse cytochrome c by dimerization. Org Biomol Chem 2011; 9:4766-9. [PMID: 21625690 DOI: 10.1039/c1ob05552f] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The peroxidase activity of horse cytochrome c was enhanced by its dimerization, where its Compound III (oxy-form) and Compound I (oxoferryl porphyrin π-cation radical) species were detected in the reactions with hydrogen peroxide and meta-chloroperbenzoic acid, respectively. These results show that oligomeric cytochrome c can contribute as a proapoptotic conformer by the increased peroxidase activity.
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Affiliation(s)
- Zhonghua Wang
- Graduate School of Materials Science, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0192, Japan
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27
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Abu Tarboush N, Jensen LMR, Feng M, Tachikawa H, Wilmot CM, Davidson VL. Functional importance of tyrosine 294 and the catalytic selectivity for the bis-Fe(IV) state of MauG revealed by replacement of this axial heme ligand with histidine . Biochemistry 2010; 49:9783-91. [PMID: 20929212 DOI: 10.1021/bi101254p] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The diheme enzyme MauG catalyzes the posttranslational modification of a precursor protein of methylamine dehydrogenase (preMADH) to complete the biosynthesis of its protein-derived tryptophan tryptophylquinone (TTQ) cofactor. It catalyzes three sequential two-electron oxidation reactions which proceed through a high-valent bis-Fe(IV) redox state. Tyr294, the unusual distal axial ligand of one c-type heme, was mutated to His, and the crystal structure of Y294H MauG in complex with preMADH reveals that this heme now has His-His axial ligation. Y294H MauG is able to interact with preMADH and participate in interprotein electron transfer, but it is unable to catalyze the TTQ biosynthesis reactions that require the bis-Fe(IV) state. This mutation affects not only the redox properties of the six-coordinate heme but also the redox and CO-binding properties of the five-coordinate heme, despite the 21 Å separation of the heme iron centers. This highlights the communication between the hemes which in wild-type MauG behave as a single diheme unit. Spectroscopic data suggest that Y294H MauG can stabilize a high-valent redox state equivalent to Fe(V), but it appears to be an Fe(IV)═O/π radical at the five-coordinate heme rather than the bis-Fe(IV) state. This compound I-like intermediate does not catalyze TTQ biosynthesis, demonstrating that the bis-Fe(IV) state, which is stabilized by Tyr294, is specifically required for this reaction. The TTQ biosynthetic reactions catalyzed by wild-type MauG do not occur via direct contact with the Fe(IV)═O heme but via long-range electron transfer through the six-coordinate heme. Thus, a critical feature of the bis-Fe(IV) species may be that it shortens the electron transfer distance from preMADH to a high-valent heme iron.
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Affiliation(s)
- Nafez Abu Tarboush
- Department of Biochemistry, University of Mississippi Medical Center, Jackson, Mississippi 39216, United States
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Enhancement of hydrogen peroxide stability of a novel Anabaena sp. DyP-type peroxidase by site-directed mutagenesis of methionine residues. Appl Microbiol Biotechnol 2010; 87:1727-36. [DOI: 10.1007/s00253-010-2603-6] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2010] [Revised: 03/31/2010] [Accepted: 04/04/2010] [Indexed: 10/19/2022]
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Casalini S, Battistuzzi G, Borsari M, Bortolotti CA, Di Rocco G, Ranieri A, Sola M. Electron Transfer Properties and Hydrogen Peroxide Electrocatalysis of Cytochrome c Variants at Positions 67 and 80. J Phys Chem B 2010; 114:1698-706. [DOI: 10.1021/jp9090365] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Affiliation(s)
- Stefano Casalini
- Contribution from the Department of Chemistry, University of Modena and Reggio Emilia, Via Campi 183, I-41100 Modena, Italy, and CNR-INFM National Center nanoStructures and bioSystems at Surfaces - S3, Via Campi 213/A, I-41100 Modena, Italy
| | - Gianantonio Battistuzzi
- Contribution from the Department of Chemistry, University of Modena and Reggio Emilia, Via Campi 183, I-41100 Modena, Italy, and CNR-INFM National Center nanoStructures and bioSystems at Surfaces - S3, Via Campi 213/A, I-41100 Modena, Italy
| | - Marco Borsari
- Contribution from the Department of Chemistry, University of Modena and Reggio Emilia, Via Campi 183, I-41100 Modena, Italy, and CNR-INFM National Center nanoStructures and bioSystems at Surfaces - S3, Via Campi 213/A, I-41100 Modena, Italy
| | - Carlo Augusto Bortolotti
- Contribution from the Department of Chemistry, University of Modena and Reggio Emilia, Via Campi 183, I-41100 Modena, Italy, and CNR-INFM National Center nanoStructures and bioSystems at Surfaces - S3, Via Campi 213/A, I-41100 Modena, Italy
| | - Giulia Di Rocco
- Contribution from the Department of Chemistry, University of Modena and Reggio Emilia, Via Campi 183, I-41100 Modena, Italy, and CNR-INFM National Center nanoStructures and bioSystems at Surfaces - S3, Via Campi 213/A, I-41100 Modena, Italy
| | - Antonio Ranieri
- Contribution from the Department of Chemistry, University of Modena and Reggio Emilia, Via Campi 183, I-41100 Modena, Italy, and CNR-INFM National Center nanoStructures and bioSystems at Surfaces - S3, Via Campi 213/A, I-41100 Modena, Italy
| | - Marco Sola
- Contribution from the Department of Chemistry, University of Modena and Reggio Emilia, Via Campi 183, I-41100 Modena, Italy, and CNR-INFM National Center nanoStructures and bioSystems at Surfaces - S3, Via Campi 213/A, I-41100 Modena, Italy
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Nakajima H, Ramanathan K, Kawaba N, Watanabe Y. Rational engineering of Thermus thermophilus cytochrome c552 to a thermally tolerant artificial peroxidase. Dalton Trans 2010; 39:3105-14. [DOI: 10.1039/b924365h] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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31
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Ayala M, Verdin J, Vazquez-Duhalt R. The prospects for peroxidase-based biorefining of petroleum fuels. BIOCATAL BIOTRANSFOR 2009. [DOI: 10.1080/10242420701379015] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Abstract
Redox-active enzymes perform many key biological reactions. The electron transfer process is complex, not only because of its versatility, but also because of the intricate and delicate modulation exerted by the protein scaffold on the redox properties of the catalytic sites. Nowadays, there is a wealth of information available about the catalytic mechanisms of redox-active enzymes and the time is propitious for the development of projects based on the protein engineering of redox-active enzymes. In this review, we aim to provide an updated account of the available methods used for protein engineering, including both genetic and chemical tools, which are usually reviewed separately. Specific applications to redox-active enzymes are mentioned within each technology, with emphasis on those cases where the generation of novel functionality was pursued. Finally, we focus on two emerging fields in the protein engineering of redox-active enzymes: the construction of novel nucleic acid-based catalysts and the remodeling of intra-molecular electron transfer networks. We consider that the future development of these areas will represent fine examples of the concurrence of chemical and genetic tools.
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Affiliation(s)
- Gloria Saab-Rincón
- Departamento de Ingeniería Celular y Biocatálisis, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, México
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Nakajima H, Ichikawa Y, Satake Y, Takatani N, Manna SK, Rajbongshi J, Mazumdar S, Watanabe Y. Engineering ofThermus thermophilusCytochromec552: Thermally Tolerant Artificial Peroxidase*. Chembiochem 2008; 9:2954-7. [DOI: 10.1002/cbic.200800599] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Towards [Cp*Rh(bpy)(H2O]2+-promoted P450 catalysis: direct regeneration of CytC. J Inorg Biochem 2008; 103:313-5. [PMID: 19087893 DOI: 10.1016/j.jinorgbio.2008.11.005] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2008] [Revised: 11/10/2008] [Accepted: 11/10/2008] [Indexed: 11/21/2022]
Abstract
The organometallic complex pentamethylcyclopentadienyl rhodium 2,2'-bipyridin ([Cp(*)Rh(bpy)(H(2)O)](2+)) was applied as regeneration catalyst for cytochrome C (CytC). Direct reduction of CytC-bound Fe(III) was achieved in this model system pointing towards a potential usefulness of this concept to promote cell-free P450 catalysis. In addition, controlled in situ provision with hydrogen peroxide was performed using [Cp(*)Rh(bpy)(H(2)O)](2+) resulting in improved CytC-catalyzed sulfoxidation of thioanisol This work represents the first step towards the direct-[Cp(*)Rh(bpy)(H(2)O)](2+) catalyzed regeneration of P450 monooxygenases and peroxidases.
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Lin HL, Myshkin E, Waskell L, Hollenberg PF. Peroxynitrite inactivation of human cytochrome P450s 2B6 and 2E1: heme modification and site-specific nitrotyrosine formation. Chem Res Toxicol 2007; 20:1612-22. [PMID: 17907788 DOI: 10.1021/tx700220e] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
This study examined the reaction of peroxynitrite (PN) with two human cytochrome P450s, P450 2B6 (2B6) and P450 2E1 (2E1). After the reaction with PN, the NADPH/reductase-supported 7-ethoxy-4-(trifluoromethyl)coumarin (EFC) deethylation activity of both P450s was decreased in a concentration-dependent manner. HPLC analysis revealed that the prosthetic heme group of 2B6 was modified but to a lesser extent than the decrease in enzymatic activity. In contrast, the heme moiety of 2E1 was not altered. These results suggest that protein modification by PN contributed to the loss in enzymatic activity of 2B6 and 2E1 but to different extents. After trypsin digestion of the control and PN-inactivated P450s, tyrosine nitration was used as a biomarker for protein modification and the addition of the nitro group was determined using electrospray ionization-liquid chromatography-tandem mass spectrometry, allowing site-specific assignment of the tyrosine residues nitrated. Tyrosine residues 354, 244, 268, and 380 in 2B6 and tyrosine residues 317, 422, 69, and 380 in 2E1 were found to be nitrated. Tyrosine 354 is the primary site of nitration in 2B6, and tyrosine residues 422 and 317 are the primary targets for nitration in 2E1. After PN exposure, the EFC catalytic activity of 2E1 supported by tert-butylhydroperoxide was not affected, and the activity of 2B6 supported by tert-butylhydroperoxide was decreased to a lesser extent than that supported by NADPH/reductase. Following exposure to PN, the levels of the reduced-CO complex were less than the content of native heme remaining. These results suggest that PN-mediated protein modification has no effect on substrate binding but may impair the interaction of the reductase with P450s, thereby inhibiting electron transfer. Homology modeling shows that Tyr422 of 2E1 is in close proximity to the FMN domain of reductase, suggesting that Tyr422 may be involved in transferring electrons from the reductase to the heme and thus may play a critical structural and functional role in the extensive activity loss following PN exposure.
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Affiliation(s)
- Hsia-Lien Lin
- Department of Pharmacology, University of Michigan and VA Medical Center, Ann Arbor, Michigan 48109, USA
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Chapter 3 Emerging biocatalytic processes. ACTA ACUST UNITED AC 2007. [DOI: 10.1016/s0167-2991(07)80243-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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Valderrama B, García-Arellano H, Giansanti S, Baratto MC, Pogni R, Vazquez-Duhalt R. Oxidative stabilization of iso‐1‐cytochromecby redox‐inspired protein engineering. FASEB J 2006; 20:1233-5. [PMID: 16720736 DOI: 10.1096/fj.05-4173fje] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Iso-1-cytochrome c, as any other hemeprotein, is able to react with hydrogen peroxide and to engage in the peroxidase cycle. However, peroxidases are irreversibly inactivated by their substrate, hydrogen peroxide. The oxidative inactivation of hemeproteins is mechanism based and arises as the consequence of unproductive electron abstraction reactions. Protein elements, such as the porphyrin ring or the protein backbone, act as simultaneous and competing electron sources even in the presence of exogenous reducing substrates, leading to a decline in activity. It is hypothetically possible to alter the intramolecular electron transfer pathways by direct replacement of low redox potential residues around the active site; as a consequence, the inactivation process would be delayed or even suppressed. To demonstrate this hypothesis, a redox-inspired strategy was implemented until an iso-1-cytochrome c variant fully stable at catalytic concentrations of hydrogen peroxide was obtained. This variant, harboring the N52I,W59F,Y67F,K79A,F82G substitutions, preserved the catalytic performance of the parental protein but achieved a 15-fold higher total-turnover number. The phenotype of this variant was reflected in the stability of its electronic components, allowing identification of a protein-based radical intermediate mechanistically similar to Compound I of classical peroxidases. The results presented here clearly demonstrate that redox-inspired protein engineering is a useful tool for the rational modulation of intramolecular electron transfer networks.
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Affiliation(s)
- Brenda Valderrama
- Department of Cellular Engineering and Biocatalysis, Biotechnology Institute, National University of Mexico, AP 510-3, Cuernavaca, México.
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Pogni R, Baratto MC, Teutloff C, Giansanti S, Ruiz-Dueñas FJ, Choinowski T, Piontek K, Martínez AT, Lendzian F, Basosi R. A tryptophan neutral radical in the oxidized state of versatile peroxidase from Pleurotus eryngii: a combined multifrequency EPR and density functional theory study. J Biol Chem 2006; 281:9517-26. [PMID: 16443605 DOI: 10.1074/jbc.m510424200] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Versatile peroxidases are heme enzymes that combine catalytic properties of lignin peroxidases and manganese peroxidases, being able to oxidize Mn(2+) as well as phenolic and non-phenolic aromatic compounds in the absence of mediators. The catalytic process (initiated by hydrogen peroxide) is the same as in classical peroxidases, with the involvement of 2 oxidizing equivalents and the formation of the so-called Compound I. This latter state contains an oxoferryl center and an organic cation radical that can be located on either the porphyrin ring or a protein residue. In this study, a radical intermediate in the reaction of versatile peroxidase from the ligninolytic fungus Pleurotus eryngii with H(2)O(2) has been characterized by multifrequency (9.4 and 94 GHz) EPR and assigned to a tryptophan residue. Comparison of experimental data and density functional theory theoretical results strongly suggests the assignment to a tryptophan neutral radical, excluding the assignment to a tryptophan cation radical or a histidine radical. Based on the experimentally determined side chain orientation and comparison with a high resolution crystal structure, the tryptophan neutral radical can be assigned to Trp(164) as the site involved in long-range electron transfer for aromatic substrate oxidation.
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Affiliation(s)
- Rebecca Pogni
- Department of Chemistry, University of Siena, 53100 Siena, Italy.
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García-Arellano H, Buenrostro-Gonzalez E, Vazquez-Duhalt R. Biocatalytic transformation of petroporphyrins by chemical modified cytochrome C. Biotechnol Bioeng 2004; 85:790-8. [PMID: 14991657 DOI: 10.1002/bit.20023] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
A semi-synthetic biocatalyst was prepared by a double chemical modification of cytochrome c. Free amino groups were modified with poly(ethylene glycol) while free carboxylic groups were alkylated to form methyl esters. The double chemically modified protein, PEG-Cyt-Met, oxidized synthetic porphyrins in a ternary solvent mixture composed by methylene chloride, methanol, and phosphate buffer. The highest activity was found in the ternary systems with low water content (5%). The use of relatively hydrophobic peroxides, such as tert-butyl and cumene hydroperoxides, extended the operational life of the biocatalyst, which, in turn, resulted in an extended oxidation of the substrates tested. PEG-Cyt-Met is able to transform asphaltenes, a highly recalcitrant petroleum fraction. The huge energetic resource found as asphaltene-rich deposits is the driving force to investigate and to innovate upgrading technologies, including biotechnological strategies.
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Heering HA, Wiertz FGM, Dekker C, de Vries S. Direct Immobilization of Native Yeast Iso-1 Cytochrome c on Bare Gold: Fast Electron Relay to Redox Enzymes and Zeptomole Protein-Film Voltammetry. J Am Chem Soc 2004; 126:11103-12. [PMID: 15339197 DOI: 10.1021/ja046737w] [Citation(s) in RCA: 103] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Cyclic voltammetry shows that yeast iso-1-cytochrome c (YCC), chemisorbed on a bare gold electrode via Cys102, exhibits fast, reversible interfacial electron transfer (k(0) = 1.8 x 10(3) s(-1)) and retains its native functionality. Vectorially immobilized YCC relays electrons to yeast cytochrome c peroxidase, and to both cytochrome cd(1) nitrite reductase (NIR) and nitric oxide reductase from Paracoccus denitrificans, thereby revealing the mechanistic properties of these enzymes. On a microelectrode, we measured nitrite turnover by approximately 80 zmol (49 000 molecules) of NIR, coadsorbed on 0.65 amol (390 000 molecules) of YCC.
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Affiliation(s)
- Hendrik A Heering
- Contribution from the Department of Biotechnology, Faculty of Applied Sciences, Delft University of Technology, Julianalaan 67, 2628 BC Delft, The Netherlands
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Bellezza F, Cipiciani A, Costantino U, Nicolis S. Catalytic activity of myoglobin immobilized on zirconium phosphonates. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2004; 20:5019-25. [PMID: 15984263 DOI: 10.1021/la0496791] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The adsorption and catalytic activity of myoglobin (Mb) on zirconium phosphonates (a-zirconium benzenephosphonate (alpha-ZrBP), a-zirconium carboxyethanephosphonate (alpha-ZrCEP), and a novel layered zirconium fluoride aminooctyl-N,N-bis(methylphosphonate) (ZrC8)) were investigated. The maximum adsorption was reached after 16 h of contact and was greater on hydrophobic supports such as alpha-ZrBP and ZrC8 compared to hydrophilic supports such as alpha-ZrCEP. The equilibrium adsorption isotherms fitted the Langmuir equation, suggesting the presence of a monolayer of protein molecules on the support surfaces. The catalytic activities of free Mb and of the obtained biocomposites were studied in terms of the oxidation of two aromatic substrates, o-phenylenediamine and 2-methoxyphenol (guaiacol), by hydrogen peroxide. The oxidation catalyzed by immobilized myoglobin followed the Michaelis-Menten kinetics, similar to oxidation by free Mb. The kinetic parameters, kcat and KM, were significantly affected by the adsorption process. Mb/alpha-ZrCEP was the most efficient biocatalyst obtained, probably because of the hydrophilic nature of the support. The effect of immobilization on the stability of Mb toward inactivation by hydrogen peroxide was also investigated, and an increased resistance was found. The biocomposites obtained can be stored at 4 degrees C for months without a significant loss of catalytic activity.
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Affiliation(s)
- Francesca Bellezza
- Laboratorio di Chimica Organica and Laboratorio di Chimica Inorganica, Dipartimento di Chimica, Università di Perugia, Via Elce di Sotto 10, 06123 Perugia, Italy
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Valderrama B, Ayala M, Vazquez-Duhalt R. Suicide inactivation of peroxidases and the challenge of engineering more robust enzymes. CHEMISTRY & BIOLOGY 2002; 9:555-65. [PMID: 12031662 DOI: 10.1016/s1074-5521(02)00149-7] [Citation(s) in RCA: 228] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
As the number of industrial applications for proteins continues to expand, the exploitation of protein engineering becomes critical. It is predicted that protein engineering can generate enzymes with new catalytic properties and create desirable, high-value, products at lower production costs. Peroxidases are ubiquitous enzymes that catalyze a variety of oxygen-transfer reactions and are thus potentially useful for industrial and biomedical applications. However, peroxidases are unstable and are readily inactivated by their substrate, hydrogen peroxide. Researchers rely on the powerful tools of molecular biology to improve the stability of these enzymes, either by protecting residues sensitive to oxidation or by devising more efficient intramolecular pathways for free-radical allocation. Here, we discuss the catalytic cycle of peroxidases and the mechanism of the suicide inactivation process to establish a broad knowledge base for future rational protein engineering.
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Affiliation(s)
- Brenda Valderrama
- Instituto de Biotecnología, Universidad Nacional Autónoma de México, AP 510-3 Cuernavaca, Morelos 62250, México.
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Prasad S, Maiti NC, Mazumdar S, Mitra S. Reaction of hydrogen peroxide and peroxidase activity in carboxymethylated cytochrome c: spectroscopic and kinetic studies. BIOCHIMICA ET BIOPHYSICA ACTA 2002; 1596:63-75. [PMID: 11983422 DOI: 10.1016/s0167-4838(02)00205-4] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The peroxidase activity of carboxymethylated cytochrome c (Cmcytc) has been investigated by spectroscopic and kinetic techniques to examine the effect of carboxymethylation on the peroxidase activity of native cytochrome c (cytc). The optical spectrum suggests that the reaction of Cmcytc with H(2)O(2) proceeds through only one intermediate, compound I. The apparent rate constant (k(app)) for the reaction was found to be 17, 72 and 210 M(-1) s(-1) at pH 7.0, 5.0 and 3.5 respectively. These values are about 60 times larger than those reported for native cytc (0.236 M(-1) s(-1) at pH 7.0), and about five orders of magnitude lower than those for classical peroxidases. Cmcytc was found to catalyse oxidation of organic and inorganic substrates. The second order rate constant for the oxidation of 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) by Cmcytc (205 [H(2)O(2)] s(-1)) is found to be larger than the corresponding value for native cytc (50 [H(2)O(2)] s(-1)) at pH 6.0. The carboxymethylation of cytc ruptures the Fe-S (Met 80) bond and increases the rate of its reaction with H(2)O(2), and its catalytic activity. The specific activity of Cmcytc was measured spectrophotometrically by the reported method using ABTS as substrate, and was found to be 288, 473 and 872 microM min(-1) mg(-1) at pH 7.0, 5.0 and 3.5 respectively. Resonance Raman studies indicated the presence of a bis-histidine coordinated form of Cmcytc at neutral pH, and the existence of a population distribution of different ligation states such as bis-histidine (HH), histidine-water (HW) and five coordinate (5C) forms at lower pH. The relative population of different species in Cmcytc was found to be HH (approximately 100%, approximately 50%, approximately 44%), HW (approximately 0%, approximately 44%, 41%) and 5C (approximately 0%, approximately 6%, 15%) at pH 7.0, 4.7 and 3.1 respectively. We have attempted to correlate the pH dependence of the reaction of Cmcytc with hydrogen peroxide and its peroxidase activity with the haem stereochemical structures observed for Cmcytc. Steady-state and time-resolved tryptophan fluorescence studies on Cmcytc were done to probe the conformational changes around the haem pocket of Cmcytc.
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Affiliation(s)
- Swati Prasad
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai-400005, India
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Abstract
Peroxidases are oxidoreductases that utilize hydrogen peroxide to catalyze oxidative reactions. A large number of peroxidases have been identified in fungal species and are being characterized at the molecular level. In this manuscript we review the current knowledge on the molecular aspects of this type of enzymes. We present an overview of the research efforts undertaken in deciphering the structural basis of the catalytic properties of fungal peroxidases and discuss molecular genetics and protein homology aspects of this enzyme class. Finally, we summarize the potential biotechnological applications of these enzymes and evaluate recent advances on their expression in heterologous systems for production purposes.
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Affiliation(s)
- Ana Conesa
- Department of Applied Microbiology and Gene Technology, TNO Nutrition and Food Research Institute, Utrechtseweg 48, 3704 HE Zeist, The Netherlands
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Gebicka L. Peroxidase-like activity of cytochrome c in the presence of anionic surfactants. RESEARCH ON CHEMICAL INTERMEDIATES 2001. [DOI: 10.1163/15685670152621988] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Morawski B, Quan S, Arnold FH. Functional expression and stabilization of horseradish peroxidase by directed evolution in Saccharomyces cerevisiae. Biotechnol Bioeng 2001; 76:99-107. [PMID: 11505379 DOI: 10.1002/bit.1149] [Citation(s) in RCA: 110] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Biotechnology applications of horseradish peroxidase (HRP) would benefit from access to tailor-made variants with greater specific activity, lower K(m) for peroxide, and higher thermostability. Starting with a mutant that is functionally expressed in Saccharomyces cerevisiae, we used random mutagenesis, recombination, and screening to identify HRP-C mutants that are more active and stable to incubation in hydrogen peroxide at 50 degrees C. A single mutation (N175S) in the HRP active site was found to improve thermal stability. Introducing this mutation into an HRP variant evolved for higher activity yielded HRP 13A7-N175S, whose half-life at 60 degrees C and pH 7.0 is three times that of wild-type (recombinant) HRP and a commercially available HRP preparation from Sigma (St. Louis, MO). The variant is also more stable in the presence of H(2)O(2), SDS, salts (NaCl and urea), and at different pH values. Furthermore, this variant is more active towards a variety of small organic substrates frequently used in diagnostic applications. Site-directed mutagenesis to replace each of the four methionine residues in HRP (M83, M181, M281, M284) with isoleucine revealed no mutation that significantly increased the enzyme's stability to hydrogen peroxide.
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Affiliation(s)
- B Morawski
- Division of Chemistry and Chemical Engineering 210-41, California Institute of Technology, Pasadena, CA 91125, USA
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