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Ignasiak-Kciuk M, Nowicka-Bauer K, Grzechowiak M, Ravnsborg T, Frąckowiak K, Jensen ON, Jaskólski M, Marciniak B. Does the presence of ground state complex between a PR-10 protein and a sensitizer affect the mechanism of sensitized photo-oxidation? Free Radic Biol Med 2023; 198:27-43. [PMID: 36738800 DOI: 10.1016/j.freeradbiomed.2023.01.022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 01/12/2023] [Accepted: 01/25/2023] [Indexed: 02/05/2023]
Abstract
The mechanisms of one-electron protein oxidation are complicated and still not well-understood. In this work, we investigated the reaction of sensitized photo-oxidation using carboxybenzophenone (CB) as a sensitizer and a PR-10 protein (MtN13) as a quencher, which is intrinsically complicated due to the complex structure of the protein and multiple possibilities of CB attack. To predict and examine the possible reactions precisely, the 3D structure of the MtN13 protein was taken into account. Our crystallographic studies revealed a specific binding of the CB molecule in the protein's hydrophobic cavity, while mass spectrometry identified the amino acid residues (Met, Tyr, Asp and Phe) creating adducts with the sensitizer, thus indicating the sites of 3CB* quenching. In addition, protein aggregation was also observed. The detailed mechanisms of CB quenching by the MtN13 molecule were elucidated by an analysis of transient products by means of time-resolved spectroscopy. The investigation of the transient and stable products formed during the protein photo-oxidation was based on the data obtained from HPLC-MS analysis of model compounds, single amino acids and dipeptides. Our proposed mechanisms of sensitized protein photo-oxidation emphasize the role of a ground state complex between the protein and the sensitizer and indicate several new and specific products arising as a result of one-electron oxidation. Based on the analysis of the transient and stable products, we have demonstrated the influence of neighboring groups, especially in the case of Tyr oxidation, where the tyrosyl radical can be formed via a direct electron transfer from Tyr to CB* or via an intramolecular electron transfer from Tyr to Met radical cation Met > S●+ or thiyl radical CysS● from neighboring oxidized groups.
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Affiliation(s)
- Marta Ignasiak-Kciuk
- Center for Advanced Technology, Adam Mickiewicz University, Poznan, Poland; Faculty of Chemistry, Adam Mickiewicz University, Poznan, Poland.
| | | | - Marta Grzechowiak
- Institute of Bioorganic Chemistry, Polish Academy of Science, Poznan, Poland
| | - Tina Ravnsborg
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
| | - Kamil Frąckowiak
- Faculty of Chemistry, Adam Mickiewicz University, Poznan, Poland
| | - Ole N Jensen
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
| | - Mariusz Jaskólski
- Institute of Bioorganic Chemistry, Polish Academy of Science, Poznan, Poland; Faculty of Chemistry, Adam Mickiewicz University, Poznan, Poland
| | - Bronisław Marciniak
- Center for Advanced Technology, Adam Mickiewicz University, Poznan, Poland; Faculty of Chemistry, Adam Mickiewicz University, Poznan, Poland
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2
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Heng H, Song G, Cai X, Sun J, Du K, Zhang X, Wang X, Feng F, Wang S. Intrinsic Mitochondrial Reactive Oxygen Species (ROS) Activate the In Situ Synthesis of Trimethine Cyanines in Cancer Cells. Angew Chem Int Ed Engl 2022; 61:e202203444. [DOI: 10.1002/anie.202203444] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2022] [Indexed: 11/10/2022]
Affiliation(s)
- Hao Heng
- Department of Polymer Science & Engineering School of Chemistry and Chemical Engineering Nanjing University Jiangsu Nanjing 210023 P. R. China
| | - Gang Song
- Beijing National Laboratory for Molecular Sciences Key Laboratory of Organic Solids Institute of Chemistry Chinese Academy of Sciences Beijing 100190 P. R. China
- College of Chemistry University of Chinese Academy of Sciences Beijing 100049 P. R. China
| | - Xuetong Cai
- Department of Polymer Science & Engineering School of Chemistry and Chemical Engineering Nanjing University Jiangsu Nanjing 210023 P. R. China
| | - Jian Sun
- Beijing National Laboratory for Molecular Sciences Key Laboratory of Organic Solids Institute of Chemistry Chinese Academy of Sciences Beijing 100190 P. R. China
| | - Ke Du
- Department of Polymer Science & Engineering School of Chemistry and Chemical Engineering Nanjing University Jiangsu Nanjing 210023 P. R. China
| | - Xiaoran Zhang
- Department of Polymer Science & Engineering School of Chemistry and Chemical Engineering Nanjing University Jiangsu Nanjing 210023 P. R. China
| | - Xia Wang
- Department of Polymer Science & Engineering School of Chemistry and Chemical Engineering Nanjing University Jiangsu Nanjing 210023 P. R. China
| | - Fude Feng
- Department of Polymer Science & Engineering School of Chemistry and Chemical Engineering Nanjing University Jiangsu Nanjing 210023 P. R. China
| | - Shu Wang
- Beijing National Laboratory for Molecular Sciences Key Laboratory of Organic Solids Institute of Chemistry Chinese Academy of Sciences Beijing 100190 P. R. China
- College of Chemistry University of Chinese Academy of Sciences Beijing 100049 P. R. China
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3
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Chakraborty S, Mukherjee P, Sengupta R. Ribonucleotide reductase: Implications of thiol S-nitrosylation and tyrosine nitration for different subunits. Nitric Oxide 2022; 127:26-43. [PMID: 35850377 DOI: 10.1016/j.niox.2022.07.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 05/20/2022] [Accepted: 07/08/2022] [Indexed: 11/20/2022]
Abstract
Ribonucleotide reductase (RNR) is a multi-subunit enzyme responsible for catalyzing the rate-limiting step in the production of deoxyribonucleotides essential for DNA synthesis and repair. The active RNR complex is composed of multimeric R1 and R2 subunits. The RNR catalysis involves the formation of tyrosyl radicals in R2 subunits and thiyl radicals in R1 subunits. Despite the quaternary structure and cofactor diversity, all the three classes of RNR have a conserved cysteine residue at the active site which is converted into a thiyl radical that initiates the substrate turnover, suggesting that the catalytic mechanism is somewhat similar for all three classes of the RNR enzyme. Increased RNR activity has been associated with malignant transformation, cancer cell growth, and tumorigenesis. Efforts concerning the understanding of RNR inhibition in designing potent RNR inhibitors/drugs as well as developing novel approaches for antibacterial, antiviral treatments, and cancer therapeutics with improved radiosensitization have been made in clinical research. This review highlights the precise and potent roles of NO in RNR inhibition by targeting both the subunits. Under nitrosative stress, the thiols of the R1 subunits have been found to be modified by S-nitrosylation and the tyrosyl radicals of the R2 subunits have been modified by nitration. In view of the recent advances and progresses in the field of nitrosative modifications and its fundamental role in signaling with implications in health and diseases, the present article focuses on the regulations of RNR activity by S-nitrosylation of thiols (R1 subunits) and nitration of tyrosyl residues (R2 subunits) which will further help in designing new drugs and therapies.
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Affiliation(s)
- Surupa Chakraborty
- Amity Institute of Biotechnology, Amity University, Kolkata, 700135, West Bengal, India
| | - Prerona Mukherjee
- Amity Institute of Biotechnology, Amity University, Kolkata, 700135, West Bengal, India
| | - Rajib Sengupta
- Amity Institute of Biotechnology, Amity University, Kolkata, 700135, West Bengal, India.
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4
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Reactive oxygen species, the trident of Neptune in the hands of hecate; role in different diseases, signaling pathways, and detection methods. Arch Biochem Biophys 2022; 728:109357. [DOI: 10.1016/j.abb.2022.109357] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Revised: 06/29/2022] [Accepted: 07/16/2022] [Indexed: 12/22/2022]
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5
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Heng H, Song G, Cai X, Sun J, Du K, Zhang X, Wang X, Feng F, Wang S. Intrinsic‐Mitochondrial‐ROS‐Activated In Situ Synthesis of Trimethine Cyanines in Cancer Cells. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202203444] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Hao Heng
- Nanjing University School of Chemistry and Chemical Engineering 163 Xianlin Avenue 210023 Nanjing CHINA
| | - Gang Song
- Institute of Chemistry Chinese Academy of Sciences Key Laboratory of Organic Solids Zhongguancun North First Street 100190 Beijing CHINA
| | - Xuetong Cai
- Nanjing University School of Chemistry and Chemical Engineering 163 Xianlin Avenue 210023 Nanjing CHINA
| | - Jian Sun
- Institute of Chemistry Chinese Academy of Sciences Key Laboratory of Organic Solids Zhongguancun North First Street 100190 Beijing CHINA
| | - Ke Du
- Nanjing University School of Chemistry and Chemical Engineering 163 Xianlin Avenue 210023 Nanjing CHINA
| | - Xiaoran Zhang
- Nanjing University School of Chemistry and Chemical Engineering 163 Xianlin Avenue 210023 Nanjing CHINA
| | - Xia Wang
- Nanjing University School of Chemistry and Chemical Engineering 163 Xianlin Avenue 210023 Nanjing CHINA
| | - Fude Feng
- Nanjing University School of Chemistry and Chemical Engineering No. 163 Xianlin Avenue, Qixia District 210023 Nanjing CHINA
| | - Shu Wang
- Institute of Chemistry Chinese Academy of Sciences Key Laboratory of Organic Solids Zhongguancun North First Street 100190 Beijing CHINA
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6
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Kosmachevskaya OV, Nasybullina EI, Shumaev KB, Novikova NN, Topunov AF. Protective Effect of Dinitrosyl Iron Complexes Bound with Hemoglobin on Oxidative Modification by Peroxynitrite. Int J Mol Sci 2021; 22:13649. [PMID: 34948445 PMCID: PMC8703631 DOI: 10.3390/ijms222413649] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 12/09/2021] [Accepted: 12/17/2021] [Indexed: 12/21/2022] Open
Abstract
Dinitrosyl iron complexes (DNICs) are a physiological form of nitric oxide (•NO) in an organism. They are able not only to deposit and transport •NO, but are also to act as antioxidant and antiradical agents. However, the mechanics of hemoglobin-bound DNICs (Hb-DNICs) protecting Hb against peroxynitrite-caused, mediated oxidative modification have not yet been scrutinized. Through EPR spectroscopy we show that Hb-DNICs are destroyed under the peroxynitrite action in a dose-dependent manner. At the same time, DNICs inhibit the oxidation of tryptophan and tyrosine residues and formation of carbonyl derivatives. They also prevent the formation of covalent crosslinks between Hb subunits and degradation of a heme group. These effects can arise from the oxoferryl heme form being reduced, and they can be connected with the ability of DNICs to directly intercept peroxynitrite and free radicals, which emerge due to its homolysis. These data show that DNICs may ensure protection from myocardial ischemia.
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Affiliation(s)
- Olga V. Kosmachevskaya
- Research Center of Biotechnology of the Russian Academy of Sciences, Bach Institute of Biochemistry, 119071 Moscow, Russia; (O.V.K.); (E.I.N.); (K.B.S.)
| | - Elvira I. Nasybullina
- Research Center of Biotechnology of the Russian Academy of Sciences, Bach Institute of Biochemistry, 119071 Moscow, Russia; (O.V.K.); (E.I.N.); (K.B.S.)
| | - Konstantin B. Shumaev
- Research Center of Biotechnology of the Russian Academy of Sciences, Bach Institute of Biochemistry, 119071 Moscow, Russia; (O.V.K.); (E.I.N.); (K.B.S.)
| | | | - Alexey F. Topunov
- Research Center of Biotechnology of the Russian Academy of Sciences, Bach Institute of Biochemistry, 119071 Moscow, Russia; (O.V.K.); (E.I.N.); (K.B.S.)
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7
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Kosmachevskaya OV, Nasybullina EI, Shumaev KB, Chumikina LV, Arabova LI, Yaglova NV, Obernikhin SS, Topunov AF. Dinitrosyl Iron Complexes with Glutathione Ligands Intercept Peroxynitrite and Protect Hemoglobin from Oxidative Modification. APPL BIOCHEM MICRO+ 2021. [DOI: 10.1134/s0003683821040098] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
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8
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Kosmachevskaya OV, Nasybullina EI, Shumaev KB, Novikova NN, Topunov AF. Effect of Iron–Nitric Oxide Complexes on the Reactivity of Hemoglobin Cysteines. APPL BIOCHEM MICRO+ 2020. [DOI: 10.1134/s0003683820050099] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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9
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Paradisi A, Johnston EM, Tovborg M, Nicoll CR, Ciano L, Dowle A, McMaster J, Hancock Y, Davies GJ, Walton PH. Formation of a Copper(II)-Tyrosyl Complex at the Active Site of Lytic Polysaccharide Monooxygenases Following Oxidation by H 2O 2. J Am Chem Soc 2019; 141:18585-18599. [PMID: 31675221 PMCID: PMC7007232 DOI: 10.1021/jacs.9b09833] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Indexed: 01/14/2023]
Abstract
Hydrogen peroxide is a cosubstrate for the oxidative cleavage of saccharidic substrates by copper-containing lytic polysaccharide monooxygenases (LPMOs). The rate of reaction of LPMOs with hydrogen peroxide is high, but it is accompanied by rapid inactivation of the enzymes, presumably through protein oxidation. Herein, we use UV-vis, CD, XAS, EPR, VT/VH-MCD, and resonance Raman spectroscopies, augmented with mass spectrometry and DFT calculations, to show that the product of reaction of an AA9 LPMO with H2O2 at higher pHs is a singlet Cu(II)-tyrosyl radical species, which is inactive for the oxidation of saccharidic substrates. The Cu(II)-tyrosyl radical center entails the formation of significant Cu(II)-(●OTyr) overlap, which in turn requires that the plane of the d(x2-y2) SOMO of the Cu(II) is orientated toward the tyrosyl radical. We propose from the Marcus cross-relation that the active site tyrosine is part of a "hole-hopping" charge-transfer mechanism formed of a pathway of conserved tyrosine and tryptophan residues, which can protect the protein active site from inactivation during uncoupled turnover.
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Affiliation(s)
- Alessandro Paradisi
- Department
of Chemistry, Centre of Excellence of Mass Spectrometry, Technology
Facility, and Department of Physics, University of York, Heslington, York YO10
5DD, United Kingdom
| | - Esther M. Johnston
- Department
of Chemistry, Centre of Excellence of Mass Spectrometry, Technology
Facility, and Department of Physics, University of York, Heslington, York YO10
5DD, United Kingdom
| | | | - Callum R. Nicoll
- Department
of Chemistry, Centre of Excellence of Mass Spectrometry, Technology
Facility, and Department of Physics, University of York, Heslington, York YO10
5DD, United Kingdom
| | - Luisa Ciano
- Department
of Chemistry, Centre of Excellence of Mass Spectrometry, Technology
Facility, and Department of Physics, University of York, Heslington, York YO10
5DD, United Kingdom
| | - Adam Dowle
- Department
of Chemistry, Centre of Excellence of Mass Spectrometry, Technology
Facility, and Department of Physics, University of York, Heslington, York YO10
5DD, United Kingdom
| | - Jonathan McMaster
- School
of Chemistry, University of Nottingham, University Park, Nottingham NG7 2RD, United Kingdom
| | - Y. Hancock
- Department
of Chemistry, Centre of Excellence of Mass Spectrometry, Technology
Facility, and Department of Physics, University of York, Heslington, York YO10
5DD, United Kingdom
- York
Cross-Disciplinary Centre for Systems Analysis, University of York, Heslington,
York YO10 5GE, United Kingdom
| | - Gideon J. Davies
- Department
of Chemistry, Centre of Excellence of Mass Spectrometry, Technology
Facility, and Department of Physics, University of York, Heslington, York YO10
5DD, United Kingdom
| | - Paul H. Walton
- Department
of Chemistry, Centre of Excellence of Mass Spectrometry, Technology
Facility, and Department of Physics, University of York, Heslington, York YO10
5DD, United Kingdom
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10
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Mason RP, Ganini D. Immuno-spin trapping of macromolecules free radicals in vitro and in vivo - One stop shopping for free radical detection. Free Radic Biol Med 2019; 131:318-331. [PMID: 30552998 DOI: 10.1016/j.freeradbiomed.2018.11.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/18/2018] [Revised: 11/03/2018] [Accepted: 11/10/2018] [Indexed: 12/14/2022]
Abstract
The only general technique that allows the unambiguous detection of free radicals is electron spin resonance (ESR). However, ESR spin trapping has severe limitations especially in biological systems. The greatest limitation of ESR is poor sensitivity relative to the low steady-state concentration of free radical adducts, which in cells and in vivo is much lower than the best sensitivity of ESR. Limitations of ESR have led to an almost desperate search for alternatives to investigate free radicals in biological systems. Here we explore the use of the immuno-spin trapping technique, which combine the specificity of the spin trapping to the high sensitivity and universal use of immunological techniques. All of the immunological techniques based on antibody binding have become available for free radical detection in a wide variety of biological systems.
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Affiliation(s)
- Ronald P Mason
- Inflammation, Immunity and Disease Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, 111 T.W. Alexander Drive, Research Triangle Park, NC 27709, USA.
| | - Douglas Ganini
- Inflammation, Immunity and Disease Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, 111 T.W. Alexander Drive, Research Triangle Park, NC 27709, USA.
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11
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The role of redox-dependent mechanisms in heme release from hemoglobin and erythrocyte hemolysates. Arch Biochem Biophys 2019; 662:111-120. [DOI: 10.1016/j.abb.2018.12.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Revised: 11/13/2018] [Accepted: 12/03/2018] [Indexed: 11/20/2022]
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12
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Takahashi M, Morikawa H. A novel role for PsbO1 in photosynthetic electron transport as suggested by its light-triggered selective nitration in Arabidopsis thaliana. PLANT SIGNALING & BEHAVIOR 2018; 13:e1513298. [PMID: 30230951 PMCID: PMC6259825 DOI: 10.1080/15592324.2018.1513298] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Revised: 08/07/2018] [Accepted: 08/10/2018] [Indexed: 06/08/2023]
Abstract
Exposure of Arabidopsis leaves to nitrogen dioxide (NO2) results in the selective nitration of specific proteins, such as PsbO1. The 9th tyrosine residue (9Tyr) of PsbO1 has been identified as the nitration site. This nitration is triggered by light and inhibited by photosynthetic electron transport inhibitors. During protein nitration, tyrosyl and NO2 radicals are formed concurrently and combine rapidly to form 3-nitrotyrosine. A selective oxidation mechanism for 9Tyr of PsbO1 is required. We postulated that, similar to 161Tyr of D1, 9Tyr of PsbO1 is selectively photo-oxidized by photosynthetic electron transport in response to illumination to a tyrosyl radical. In corroboration, after reappraising our oxygen evolution analysis, the nitration of PsbO1 proved responsible for decreased oxygen evolution from the thylakoid membranes. NO2 is reportedly taken into cells as nitrous acid, which dissociates to form NO2-. NO2- may be oxidized into NO2 by the oxygen-evolving complex. Light may synchronize this reaction with tyrosyl radical formation. These findings suggest a novel role for PsbO1 in photosynthetic electron transport.
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Affiliation(s)
- Misa Takahashi
- Department of Mathematical and Life Sciences, Hiroshima University, Higashi-Hiroshima, Japan
| | - Hiromichi Morikawa
- Department of Mathematical and Life Sciences, Hiroshima University, Higashi-Hiroshima, Japan
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13
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Kumar A, Ganini D, Mason RP. Role of cytochrome c in α-synuclein radical formation: implications of α-synuclein in neuronal death in Maneb- and paraquat-induced model of Parkinson's disease. Mol Neurodegener 2016; 11:70. [PMID: 27884192 PMCID: PMC5122029 DOI: 10.1186/s13024-016-0135-y] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Accepted: 11/03/2016] [Indexed: 11/30/2022] Open
Abstract
Background The pathological features of Parkinson’s disease (PD) include an abnormal accumulation of α-synuclein in the surviving dopaminergic neurons. Though PD is multifactorial, several epidemiological reports show an increased incidence of PD with co-exposure to pesticides such as Maneb and paraquat (MP). In pesticide-related PD, mitochondrial dysfunction and α-synuclein oligomers have been strongly implicated, but the link between the two has not yet been understood. Similarly, the biological effects of α-synuclein or its radical chemistry in PD is largely unknown. Mitochondrial dysfunction during PD pathogenesis leads to release of cytochrome c in the cytosol. Once in the cytosol, cytochrome c has one of two fates: It either binds to apaf1 and initiates apoptosis or can act as a peroxidase. We hypothesized that as a peroxidase, cytochrome c leaked out from mitochondria can form radicals on α-synuclein and initiate its oligomerization. Method Samples from controls, and MP co-exposed wild-type and α-synuclein knockout mice were studied using immuno-spin trapping, confocal microscopy, immunohistochemistry, and microarray experiments. Results Experiments with MP co-exposed mice showed cytochrome c release in cytosol and its co-localization with α-synuclein. Subsequently, we used immuno-spin trapping method to detect the formation of α-synuclein radical in samples from an in vitro reaction mixture consisting of cytochrome c, α-synuclein, and hydrogen peroxide. These experiments indicated that cytochrome c plays a role in α-synuclein radical formation and oligomerization. Experiments with MP co-exposed α-synuclein knockout mice, in which cytochrome c-α synuclein co-localization and interaction cannot occur, mice showed diminished protein radical formation and neuronal death, compared to wild-type MP co-exposed mice. Microarray data from MP co-exposed wild-type and α-synuclein knockout mice further showed that the absence of α-synuclein per se or its co-localization with cytochrome c confers protection from MP co-exposure, as several important pathways were unaffected in α-synuclein knockout mice. Conclusions Altogether, these results show that peroxidase activity of cytochrome c contributes to α-synuclein radical formation and oligomerization, and that α-synuclein, through its co-localization with cytochrome c or on its own, affects several biological pathways which contribute to increased neuronal death in an MP-induced model of PD. Electronic supplementary material The online version of this article (doi:10.1186/s13024-016-0135-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Ashutosh Kumar
- Free Radical Biology Group, Immunity, Inflammation, and Disease Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, 111 T.W. Alexander Dr., Research Triangle Park, Durham, NC, 27709, USA.
| | - Douglas Ganini
- Free Radical Biology Group, Immunity, Inflammation, and Disease Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, 111 T.W. Alexander Dr., Research Triangle Park, Durham, NC, 27709, USA
| | - Ronald P Mason
- Free Radical Biology Group, Immunity, Inflammation, and Disease Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, 111 T.W. Alexander Dr., Research Triangle Park, Durham, NC, 27709, USA
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14
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Mason RP. Imaging free radicals in organelles, cells, tissue, and in vivo with immuno-spin trapping. Redox Biol 2016; 8:422-9. [PMID: 27203617 PMCID: PMC4878322 DOI: 10.1016/j.redox.2016.04.003] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Revised: 04/11/2016] [Accepted: 04/15/2016] [Indexed: 01/01/2023] Open
Abstract
The accurate and sensitive detection of biological free radicals in a reliable manner is required to define the mechanistic roles of such species in biochemistry, medicine and toxicology. Most of the techniques currently available are either not appropriate to detect free radicals in cells and tissues due to sensitivity limitations (electron spin resonance, ESR) or subject to artifacts that make the validity of the results questionable (fluorescent probe-based analysis). The development of the immuno-spin trapping technique overcomes all these difficulties. This technique is based on the reaction of amino acid- and DNA base-derived radicals with the spin trap 5, 5-dimethyl-1-pyrroline N-oxide (DMPO) to form protein- and DNA-DMPO nitroxide radical adducts, respectively. These adducts have limited stability and decay to produce the very stable macromolecule-DMPO-nitrone product. This stable product can be detected by mass spectrometry, NMR or immunochemistry by the use of anti-DMPO nitrone antibodies. The formation of macromolecule-DMPO-nitrone adducts is based on the selective reaction of free radical addition to the spin trap and is thus not subject to artifacts frequently encountered with other methods for free radical detection. The selectivity of spin trapping for free radicals in biological systems has been proven by ESR. Immuno-spin trapping is proving to be a potent, sensitive (a million times higher sensitivity than ESR), and easy (not quantum mechanical) method to detect low levels of macromolecule-derived radicals produced in vitro and in vivo. Anti-DMPO antibodies have been used to determine the distribution of free radicals in cells and tissues and even in living animals. In summary, the invention of the immuno-spin trapping technique has had a major impact on the ability to accurately and sensitively detect biological free radicals and, subsequently, on our understanding of the role of free radicals in biochemistry, medicine and toxicology.
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Affiliation(s)
- Ronald Paul Mason
- Immunity, Inflammation, and Disease Laboratory, National Institute of Environmental Health Sciences, NIH, Research Triangle Park, NC 27709, USA.
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15
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Paviani V, Queiroz RF, Marques EF, Di Mascio P, Augusto O. Production of lysozyme and lysozyme-superoxide dismutase dimers bound by a ditryptophan cross-link in carbonate radical-treated lysozyme. Free Radic Biol Med 2015. [PMID: 26197052 DOI: 10.1016/j.freeradbiomed.2015.07.015] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Despite extensive investigation of the irreversible oxidations undergone by proteins in vitro and in vivo, the products formed from the oxidation of Trp residues remain incompletely understood. Recently, we characterized a ditryptophan cross-link produced by the recombination of hSOD1-tryptophanyl radicals generated from attack of the carbonate radical produced during the bicarbonate-dependent peroxidase activity of the enzyme. Here, we examine whether the ditryptophan cross-link is produced by the attack of the carbonate radical on proteins other than hSOD1. To this end, we treated hen egg white lysozyme with photolytically and enzymatically generated carbonate radical. The radical yields were estimated and the lysozyme modifications were analyzed by SDS-PAGE, western blot, enzymatic activity and MS/MS analysis. Lysozyme oxidation by both systems resulted in its inactivation and dimerization. Lysozyme treated with the photolytic system presented monomers oxidized to hydroxy-tryptophan at Trp(28) and Trp(123) and N-formylkynurenine at Trp(28), Trp(62) and Trp(123). Lysozyme treated with the enzymatic system rendered monomers oxidized to N-formylkynurenine at Trp(28). The dimers were characterized as lysozyme-Trp(28)-Trp(28)-lysozyme and lysozyme-Trp(28)-Trp(32)-hSOD1. The results further demonstrate that the carbonate radical is prone to causing biomolecule cross-linking and hence, may be a relevant player in pathological mechanisms. The possibility of exploring the formation of ditryptophan cross-links as a carbonate radical biomarker is discussed.
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Affiliation(s)
- Verônica Paviani
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo
| | - Raphael F Queiroz
- Departamento de Química e Exatas, Universidade Estadual do Sudoeste da Bahia
| | - Emerson F Marques
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo
| | - Paolo Di Mascio
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo
| | - Ohara Augusto
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo.
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16
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Trujillo M, Alvarez B, Radi R. One- and two-electron oxidation of thiols: mechanisms, kinetics and biological fates. Free Radic Res 2015; 50:150-71. [PMID: 26329537 DOI: 10.3109/10715762.2015.1089988] [Citation(s) in RCA: 93] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The oxidation of biothiols participates not only in the defense against oxidative damage but also in enzymatic catalytic mechanisms and signal transduction processes. Thiols are versatile reductants that react with oxidizing species by one- and two-electron mechanisms, leading to thiyl radicals and sulfenic acids, respectively. These intermediates, depending on the conditions, participate in further reactions that converge on different stable products. Through this review, we will describe the biologically relevant species that are able to perform these oxidations and we will analyze the mechanisms and kinetics of the one- and two-electron reactions. The processes undergone by typical low-molecular-weight thiols as well as the particularities of specific thiol proteins will be described, including the molecular determinants proposed to account for the extraordinary reactivities of peroxidatic thiols. Finally, the main fates of the thiyl radical and sulfenic acid intermediates will be summarized.
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Affiliation(s)
- Madia Trujillo
- a Departamento de Bioquímica , Facultad de Medicina, Universidad de la República , Montevideo , Uruguay .,b Center for Free Radical and Biomedical Research , Universidad de la República , Montevideo , Uruguay , and
| | - Beatriz Alvarez
- b Center for Free Radical and Biomedical Research , Universidad de la República , Montevideo , Uruguay , and.,c Laboratorio de Enzimología, Facultad de Ciencias , Universidad de la República , Montevideo , Uruguay
| | - Rafael Radi
- a Departamento de Bioquímica , Facultad de Medicina, Universidad de la República , Montevideo , Uruguay .,b Center for Free Radical and Biomedical Research , Universidad de la República , Montevideo , Uruguay , and
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17
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Vallelian F, Garcia-Rubio I, Puglia M, Kahraman A, Deuel JW, Engelsberger WR, Mason RP, Buehler PW, Schaer DJ. Spin trapping combined with quantitative mass spectrometry defines free radical redistribution within the oxidized hemoglobin:haptoglobin complex. Free Radic Biol Med 2015; 85:259-68. [PMID: 25933590 DOI: 10.1016/j.freeradbiomed.2015.04.023] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Revised: 03/31/2015] [Accepted: 04/20/2015] [Indexed: 11/24/2022]
Abstract
Extracellular or free hemoglobin (Hb) accumulates during hemolysis, tissue damage, and inflammation. Heme-triggered oxidative reactions can lead to diverse structural modifications of lipids and proteins, which contribute to the propagation of tissue damage. One important target of Hb׳s peroxidase reactivity is its own globin structure. Amino acid oxidation and crosslinking events destabilize the protein and ultimately cause accumulation of proinflammatory and cytotoxic Hb degradation products. The Hb scavenger haptoglobin (Hp) attenuates oxidation-induced Hb degradation. In this study we show that in the presence of hydrogen peroxide (H2O2), Hb and the Hb:Hp complex share comparable peroxidative reactivity and free radical generation. While oxidation of both free Hb and Hb:Hp complex generates a common tyrosine-based free radical, the spin-trapping reaction with 5,5-dimethyl-1-pyrroline N-oxide (DMPO) yields dissimilar paramagnetic products in Hb and Hb:Hp, suggesting that radicals are differently redistributed within the complex before reacting with the spin trap. With LC-MS(2) mass spectrometry we assigned multiple known and novel DMPO adduct sites. Quantification of these adducts suggested that the Hb:Hp complex formation causes extensive delocalization of accessible free radicals with drastic reduction of the major tryptophan and cysteine modifications in the β-globin chain of the Hb:Hp complex, including decreased βCys93 DMPO adduction. In contrast, the quantitative changes in DMPO adduct formation on Hb:Hp complex formation were less pronounced in the Hb α-globin chain. In contrast to earlier speculations, we found no evidence that free Hb radicals are delocalized to the Hp chain of the complex. The observation that Hb:Hp complex formation alters free radical distribution in Hb may help to better understand the structural basis for Hp as an antioxidant protein.
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Affiliation(s)
| | - Ines Garcia-Rubio
- Laboratory of Physical Chemistry, ETH Zürich, Switzerland; Centro Universitario de la Defensa, carretera de Huesca, Zaragoza, Spain
| | - Michele Puglia
- Division of Internal Medicine, University Hospital, Zurich, Switzerland; Functional Genomics Center, University of Zurich, Switzerland
| | - Abdullah Kahraman
- Institute of Molecular Life Sciences, University of Zurich, Switzerland
| | - Jeremy W Deuel
- Division of Internal Medicine, University Hospital, Zurich, Switzerland
| | | | - Ronald P Mason
- Laboratory of Toxicology & Pharmacology, NIEHS/NIH, Research Triangle Park, NC, USA
| | - Paul W Buehler
- Center of Biologics Evaluation and Research, Food and Drug Administration, Bethesda, MD, USA
| | - Dominik J Schaer
- Division of Internal Medicine, University Hospital, Zurich, Switzerland; Institute of Evolutionary Medicine, University of Zurich, Switzerland.
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18
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Lesslie M, Osburn S, van Stipdonk MJ, Ryzhov V. Gas-phase tyrosine-to-cysteine radical migration in model systems. EUROPEAN JOURNAL OF MASS SPECTROMETRY (CHICHESTER, ENGLAND) 2015; 21:589-597. [PMID: 26307738 DOI: 10.1255/ejms.1341] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Radical migration, both intramolecular and intermolecular, from the tyrosine phenoxyl radical Tyr(O(∙)) to the cysteine radical Cys(S(∙)) in model peptide systems was observed in the gas phase. Ion-molecule reactions (IMRs) between the radical cation of homotyrosine and propyl thiol resulted in a fast hydrogen atom transfer. In addition, radical cations of the peptide LysTyrCys were formed via two different methods, affording regiospecific production of Tyr(O(∙)) or Cys(S(∙)) radicals. Collision-induced dissociation of these isomeric species displayed evidence of radical migration from the oxygen to sulfur, but not for the reverse process. This was supported by theoretical calculations, which showed the Cys(S(∙)) radical slightly lower in energy than the Tyr(O(∙)) isomer. IMRs of the LysTyrCys radical cation with allyl iodide further confirmed these findings. A mechanism for radical migration involving a proton shuttle by the C-terminal carboxylic group is proposed.
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Affiliation(s)
- Michael Lesslie
- Department of Chemistry and Biochemistry, and Center for Biochemical and Biophysical Sciences, Northern Illinois University, DeKalb, Illinois 60115, USA.
| | - Sandra Osburn
- Department of Chemistry and Biochemistry, Duquesne University, 600 Forbes Avenue, Pittsburgh, Pennsylvania15282, USA.
| | - Michael J van Stipdonk
- Department of Chemistry and Biochemistry, Duquesne University, 600 Forbes Avenue, Pittsburgh, Pennsylvania 15282, USA.
| | - Victor Ryzhov
- Department of Chemistry and Biochemistry, and Center for Biochemical and Biophysical Sciences, Northern Illinois University, DeKalb, Illinois 60115, USA.
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19
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Liu X, Jiang L, Li J, Wang L, Yu Y, Zhou Q, Lv X, Gong W, Lu Y, Wang J. Significant expansion of fluorescent protein sensing ability through the genetic incorporation of superior photo-induced electron-transfer quenchers. J Am Chem Soc 2014; 136:13094-7. [PMID: 25197956 DOI: 10.1021/ja505219r] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Photo-induced electron transfer (PET) is ubiquitous for photosynthesis and fluorescent sensor design. However, genetically coded PET sensors are underdeveloped, due to the lack of methods to site-specifically install PET probes on proteins. Here we describe a family of acid and Mn(III) turn-on fluorescent protein (FP) sensors, named iLovU, based on PET and the genetic incorporation of superior PET quenchers in the fluorescent flavoprotein iLov. Using the iLovU PET sensors, we monitored the cytoplasmic acidification process, and achieved Mn(III) fluorescence sensing for the first time. The iLovU sensors should be applicable for studying pH changes in living cells, monitoring biogentic Mn(III) in the environment, and screening for efficient manganese peroxidase, which is highly desirable for lignin degradation and biomass conversion. Our work establishes a platform for many more protein PET sensors, facilitates the de novo design of metalloenzymes harboring redox active residues, and expands our ability to probe protein conformational dynamics.
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Affiliation(s)
- Xiaohong Liu
- Laboratory of RNA Biology, Institute of Biophysics, Chinese Academy of Sciences , Chaoyang District, Beijing, 100101, China
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20
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Iqbal A, Paviani V, Moretti AI, Laurindo FR, Augusto O. Oxidation, inactivation and aggregation of protein disulfide isomerase promoted by the bicarbonate-dependent peroxidase activity of human superoxide dismutase. Arch Biochem Biophys 2014; 557:72-81. [DOI: 10.1016/j.abb.2014.06.013] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2014] [Revised: 06/05/2014] [Accepted: 06/11/2014] [Indexed: 11/29/2022]
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21
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deBoer TR, Palomino RI, Idiga SO, Millhauser GL, Mascharak PK. Tyrosine nitration in peptides by peroxynitrite generated in situ in a light-controlled platform: Effects of pH and thiols. J Inorg Biochem 2014; 138:24-30. [DOI: 10.1016/j.jinorgbio.2014.04.018] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2014] [Revised: 04/25/2014] [Accepted: 04/28/2014] [Indexed: 01/03/2023]
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22
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Kumar A, Chen SH, Kadiiska MB, Hong JS, Zielonka J, Kalyanaraman B, Mason RP. Inducible nitric oxide synthase is key to peroxynitrite-mediated, LPS-induced protein radical formation in murine microglial BV2 cells. Free Radic Biol Med 2014; 73:51-9. [PMID: 24746617 PMCID: PMC4111989 DOI: 10.1016/j.freeradbiomed.2014.04.014] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/16/2014] [Revised: 04/02/2014] [Accepted: 04/09/2014] [Indexed: 11/24/2022]
Abstract
Microglia are the resident immune cells in the brain. Microglial activation is characteristic of several inflammatory and neurodegenerative diseases including Alzheimer's disease, multiple sclerosis, and Parkinson's disease. Though lipopolysaccharide (LPS)-induced microglial activation in models of Parkinson's disease is well documented, the free radical-mediated protein radical formation and its underlying mechanism during LPS-induced microglial activation are not known. Here we have used immuno-spin trapping and RNA interference to investigate the role of inducible nitric oxide synthase (iNOS) in peroxynitrite-mediated protein radical formation in murine microglial BV2 cells treated with LPS. Treatment of BV2 cells with LPS resulted in morphological changes, induction of iNOS, and increased protein radical formation. Pretreatments with FeTPPS (a peroxynitrite decomposition catalyst), L-NAME (total NOS inhibitor), 1400W (iNOS inhibitor), and apocynin significantly attenuated LPS-induced protein radical formation and tyrosine nitration. Results obtained with coumarin-7-boronic acid, a highly specific probe for peroxynitrite detection, correlated with LPS-induced tyrosine nitration, which demonstrated involvement of peroxynitrite in protein radical formation. A similar degree of protection conferred by 1400W and L-NAME led us to conclude that only iNOS, and no other forms of NOS, is involved in LPS-induced peroxynitrite formation. Subsequently, siRNA for iNOS, the iNOS-specific inhibitor 1400W, the NF-κB inhibitor PDTC, and the p38 MAPK inhibitor SB202190 was used to inhibit iNOS directly or indirectly. Inhibition of iNOS precisely correlated with decreased protein radical formation in LPS-treated BV2 cells. The time course of protein radical formation also matched the time course of iNOS expression. Taken together, these results prove the role of iNOS in peroxynitrite-mediated protein radical formation in LPS-treated microglial BV2 cells.
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Affiliation(s)
- Ashutosh Kumar
- Free Radical Metabolism Group, Laboratory of Toxicology & Pharmacology, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709, USA.
| | - Shih-Heng Chen
- Neuropharmacology Group, Laboratory of Toxicology & Pharmacology, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709, USA
| | - Maria B Kadiiska
- Free Radical Metabolism Group, Laboratory of Toxicology & Pharmacology, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709, USA
| | - Jau-Shyong Hong
- Neuropharmacology Group, Laboratory of Toxicology & Pharmacology, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709, USA
| | - Jacek Zielonka
- Department of Biophysics and Free Radical Research Center, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Balaraman Kalyanaraman
- Department of Biophysics and Free Radical Research Center, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Ronald P Mason
- Free Radical Metabolism Group, Laboratory of Toxicology & Pharmacology, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709, USA
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23
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Chen X, Ma G, Sun W, Dai H, Xiao D, Zhang Y, Qin X, Liu Y, Bu Y. Water Promoting Electron Hole Transport between Tyrosine and Cysteine in Proteins via a Special Mechanism: Double Proton Coupled Electron Transfer. J Am Chem Soc 2014; 136:4515-24. [DOI: 10.1021/ja406340z] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Xiaohua Chen
- School
of Chemistry and Chemical Engineering, Chongqing University, Chongqing, 400030, China
| | - Guangcai Ma
- School
of Chemistry and Chemical Engineering, Shandong University, Jinan, Shandong 250100, China
| | - Weichao Sun
- School
of Chemistry and Chemical Engineering, Chongqing University, Chongqing, 400030, China
| | - Hongjing Dai
- School
of Chemistry and Chemical Engineering, Chongqing University, Chongqing, 400030, China
| | - Dong Xiao
- School
of Chemistry and Chemical Engineering, Chongqing University, Chongqing, 400030, China
| | - Yanfang Zhang
- School
of Chemistry and Chemical Engineering, Chongqing University, Chongqing, 400030, China
| | - Xin Qin
- School
of Chemistry and Chemical Engineering, Chongqing University, Chongqing, 400030, China
| | - Yongjun Liu
- School
of Chemistry and Chemical Engineering, Shandong University, Jinan, Shandong 250100, China
| | - Yuxiang Bu
- School
of Chemistry and Chemical Engineering, Shandong University, Jinan, Shandong 250100, China
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24
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Martinez A, Peluffo G, Petruk AA, Hugo M, Piñeyro D, Demicheli V, Moreno DM, Lima A, Batthyány C, Durán R, Robello C, Martí MA, Larrieux N, Buschiazzo A, Trujillo M, Radi R, Piacenza L. Structural and molecular basis of the peroxynitrite-mediated nitration and inactivation of Trypanosoma cruzi iron-superoxide dismutases (Fe-SODs) A and B: disparate susceptibilities due to the repair of Tyr35 radical by Cys83 in Fe-SODB through intramolecular electron transfer. J Biol Chem 2014; 289:12760-78. [PMID: 24616096 DOI: 10.1074/jbc.m113.545590] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Trypanosoma cruzi, the causative agent of Chagas disease, contains exclusively iron-dependent superoxide dismutases (Fe-SODs) located in different subcellular compartments. Peroxynitrite, a key cytotoxic and oxidizing effector biomolecule, reacted with T. cruzi mitochondrial (Fe-SODA) and cytosolic (Fe-SODB) SODs with second order rate constants of 4.6 ± 0.2 × 10(4) M(-1) s(-1) and 4.3 ± 0.4 × 10(4) M(-1) s(-1) at pH 7.4 and 37 °C, respectively. Both isoforms are dose-dependently nitrated and inactivated by peroxynitrite. Susceptibility of T. cruzi Fe-SODA toward peroxynitrite was similar to that reported previously for Escherichia coli Mn- and Fe-SODs and mammalian Mn-SOD, whereas Fe-SODB was exceptionally resistant to oxidant-mediated inactivation. We report mass spectrometry analysis indicating that peroxynitrite-mediated inactivation of T. cruzi Fe-SODs is due to the site-specific nitration of the critical and universally conserved Tyr(35). Searching for structural differences, the crystal structure of Fe-SODA was solved at 2.2 Å resolution. Structural analysis comparing both Fe-SOD isoforms reveals differences in key cysteines and tryptophan residues. Thiol alkylation of Fe-SODB cysteines made the enzyme more susceptible to peroxynitrite. In particular, Cys(83) mutation (C83S, absent in Fe-SODA) increased the Fe-SODB sensitivity toward peroxynitrite. Molecular dynamics, electron paramagnetic resonance, and immunospin trapping analysis revealed that Cys(83) present in Fe-SODB acts as an electron donor that repairs Tyr(35) radical via intramolecular electron transfer, preventing peroxynitrite-dependent nitration and consequent inactivation of Fe-SODB. Parasites exposed to exogenous or endogenous sources of peroxynitrite resulted in nitration and inactivation of Fe-SODA but not Fe-SODB, suggesting that these enzymes play distinctive biological roles during parasite infection of mammalian cells.
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Affiliation(s)
- Alejandra Martinez
- From the Departamento de Bioquímica and Center for Free Radical and Biomedical Research, Facultad de Medicina, Universidad de la República, Montevideo 11800, Uruguay
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25
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Zeida A, Guardia CM, Lichtig P, Perissinotti LL, Defelipe LA, Turjanski A, Radi R, Trujillo M, Estrin DA. Thiol redox biochemistry: insights from computer simulations. Biophys Rev 2014; 6:27-46. [PMID: 28509962 PMCID: PMC5427810 DOI: 10.1007/s12551-013-0127-x] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2013] [Accepted: 12/03/2013] [Indexed: 12/13/2022] Open
Abstract
Thiol redox chemical reactions play a key role in a variety of physiological processes, mainly due to the presence of low-molecular-weight thiols and cysteine residues in proteins involved in catalysis and regulation. Specifically, the subtle sensitivity of thiol reactivity to the environment makes the use of simulation techniques extremely valuable for obtaining microscopic insights. In this work we review the application of classical and quantum-mechanical atomistic simulation tools to the investigation of selected relevant issues in thiol redox biochemistry, such as investigations on (1) the protonation state of cysteine in protein, (2) two-electron oxidation of thiols by hydroperoxides, chloramines, and hypochlorous acid, (3) mechanistic and kinetics aspects of the de novo formation of disulfide bonds and thiol-disulfide exchange, (4) formation of sulfenamides, (5) formation of nitrosothiols and transnitrosation reactions, and (6) one-electron oxidation pathways.
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Affiliation(s)
- Ari Zeida
- Departamento de Química Inorgánica, Analítica y Química-Física and INQUIMAE-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pab. 2, C1428EHA, Buenos Aires, Argentina
| | - Carlos M Guardia
- Departamento de Química Inorgánica, Analítica y Química-Física and INQUIMAE-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pab. 2, C1428EHA, Buenos Aires, Argentina
| | - Pablo Lichtig
- Departamento de Química Inorgánica, Analítica y Química-Física and INQUIMAE-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pab. 2, C1428EHA, Buenos Aires, Argentina
| | - Laura L Perissinotti
- Institute for Biocomplexity and Informatics, Department of Biological Sciences, University of Calgary, 2500 University Drive, Calgary, AB, Canada, T2N 2N4
| | - Lucas A Defelipe
- Departamento de Química Biológica and INQUIMAE-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pab. 2, C1428EHA, Buenos Aires, Argentina
| | - Adrián Turjanski
- Departamento de Química Biológica and INQUIMAE-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pab. 2, C1428EHA, Buenos Aires, Argentina
| | - Rafael Radi
- Departamento de Bioquímica and Center for Free Radical and Biomedical Research, Facultad de Medicina, Universidad de la República, Av. Gral Flores 2125, CP 11800, Montevideo, Uruguay
| | - Madia Trujillo
- Departamento de Bioquímica and Center for Free Radical and Biomedical Research, Facultad de Medicina, Universidad de la República, Av. Gral Flores 2125, CP 11800, Montevideo, Uruguay
| | - Darío A Estrin
- Departamento de Química Inorgánica, Analítica y Química-Física and INQUIMAE-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pab. 2, C1428EHA, Buenos Aires, Argentina.
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26
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Towner RA, Smith N, Saunders D, Lupu F, Silasi-Mansat R, West M, Ramirez DC, Gomez-Mejiba SE, Bonini MG, Mason RP, Ehrenshaft M, Hensley K. In vivo detection of free radicals using molecular MRI and immuno-spin trapping in a mouse model for amyotrophic lateral sclerosis. Free Radic Biol Med 2013; 63:351-60. [PMID: 23722162 DOI: 10.1016/j.freeradbiomed.2013.05.026] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/13/2012] [Revised: 05/13/2013] [Accepted: 05/17/2013] [Indexed: 11/19/2022]
Abstract
Free radicals associated with oxidative stress play a major role in amyotrophic lateral sclerosis (ALS). By combining immuno-spin trapping and molecular magnetic resonance imaging, in vivo trapped radical adducts were detected in the spinal cords of SOD1(G93A)-transgenic (Tg) mice, a model for ALS. For this study, the nitrone spin trap DMPO (5,5-dimethyl-1-pyrroline N-oxide) was administered (ip) over 5 days before administration (iv) of an anti-DMPO probe (anti-DMPO antibody covalently bound to an albumin-gadolinium-diethylenetriamine pentaacetic acid-biotin MRI contrast agent) to trap free radicals. MRI was used to detect the presence of the anti-DMPO radical adducts by a significant sustained increase in MR signal intensities (p < 0.05) or anti-DMPO probe concentrations measured from T₁ relaxations (p < 0.01). The biotin moiety of the anti-DMPO probe was targeted with fluorescence-labeled streptavidin to locate the probe in excised tissues. Negative controls included either Tg ALS mice initially administered saline rather than DMPO followed by the anti-DMPO probe or non-Tg mice initially administered DMPO and then the anti-DMPO probe. The anti-DMPO probe was found to bind to neurons via colocalization fluorescence microscopy. DMPO adducts were also confirmed in diseased/nondiseased tissues from animals administered DMPO. Apparent diffusion coefficients from diffusion-weighted images of spinal cords from Tg mice were significantly elevated (p < 0.001) compared to wild-type controls. This is the first report regarding the detection of in vivo trapped radical adducts in an ALS model. This novel, noninvasive, in vivo diagnostic method can be applied to investigate the involvement of free radical mechanisms in ALS rodent models.
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Affiliation(s)
- Rheal A Towner
- Advanced Magnetic Resonance Center, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA.
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27
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Gomez-Mejiba SE, Zhai Z, Della-Vedova MC, Muñoz MD, Chatterjee S, Towner RA, Hensley K, Floyd RA, Mason RP, Ramirez DC. Immuno-spin trapping from biochemistry to medicine: advances, challenges, and pitfalls. Focus on protein-centered radicals. Biochim Biophys Acta Gen Subj 2013; 1840:722-9. [PMID: 23644035 DOI: 10.1016/j.bbagen.2013.04.039] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2013] [Revised: 04/24/2013] [Accepted: 04/27/2013] [Indexed: 01/04/2023]
Abstract
BACKGROUND Immuno-spin trapping (IST) is based on the reaction of a spin trap with a free radical to form a stable nitrone adduct, followed by the use of antibodies, rather than traditional electron paramagnetic resonance spectroscopy, to detect the nitrone adduct. IST has been successfully applied to mechanistic in vitro studies, and recently, macromolecule-centered radicals have been detected in models of drug-induced agranulocytosis, hepatotoxicity, cardiotoxicity, and ischemia/reperfusion, as well as in models of neurological, metabolic and immunological diseases. SCOPE OF THE REVIEW To critically evaluate advances, challenges, and pitfalls as well as the scientific opportunities of IST as applied to the study of protein-centered free radicals generated in stressed organelles, cells, tissues and animal models of disease and exposure. MAJOR CONCLUSIONS Because the spin trap has to be present at high enough concentrations in the microenvironment where the radical is formed, the possible effects of the spin trap on gene expression, metabolism and cell physiology have to be considered in the use of IST and in the interpretation of results. These factors have not yet been thoroughly dealt with in the literature. GENERAL SIGNIFICANCE The identification of radicalized proteins during cell/tissue response to stressors will help define their role in the complex cellular response to stressors and pathogenesis; however, the fidelity of spin trapping/immuno-detection and the effects of the spin trap on the biological system should be considered. This article is part of a Special Issue entitled Current methods to study reactive oxygen species - pros and cons and biophysics of membrane proteins. Guest Editor: Christine Winterbourn.
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Affiliation(s)
- Sandra E Gomez-Mejiba
- Laboratory of Experimental Medicine and Therapeutics, Institute Multidisciplinary of Biological Investigations-San Luis (IMIBIO-SL), National Bureau of Science and Technology (CONICET) and National University of San Luis, San Luis, 5700 San Luis, Argentina
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28
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Wang Y, Lin A, Loake GJ, Chu C. H2O2-induced leaf cell death and the crosstalk of reactive nitric/oxygen species. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2013; 55:202-8. [PMID: 23331502 DOI: 10.1111/jipb.12032] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
In plants, the chloroplast is the main reactive oxygen species (ROS) producing site under high light stress. Catalase (CAT), which decomposes hydrogen peroxide (H2 O2 ), is one of the controlling enzymes that maintains leaf redox homeostasis. The catalase mutants with reduced leaf catalase activity from different plant species exhibit an H2 O2 -induced leaf cell death phenotype. This phenotype was differently affected by light intensity or photoperiod, which may be caused by plant species, leaf redox status or growth conditions. In the rice CAT mutant nitric oxide excess 1 (noe1), higher H2 O2 levels induced the generation of nitric oxide (NO) and higher S-nitrosothiol (SNO) levels, suggesting that NO acts as an important endogenous mediator in H2 O2 -induced leaf cell death. As a free radical, NO could also react with other intracellular and extracellular targets and form a series of related molecules, collectively called reactive nitrogen species (RNS). Recent studies have revealed that both RNS and ROS are important partners in plant leaf cell death. Here, we summarize the recent progress on H2 O2 -induced leaf cell death and the crosstalk of RNS and ROS signals in the plant hypersensitive response (HR), leaf senescence, and other forms of leaf cell death triggered by diverse environmental conditions. [Formula: see text] [ Chengcai Chu (Corresponding author)].
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Affiliation(s)
- Yiqin Wang
- State Key Laboratory of Plant Genomics and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, the Chinese Academy of Sciences, Beijing 100101, China
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29
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Vitturi DA, Sun CW, Harper VM, Thrash-Williams B, Cantu-Medellin N, Chacko BK, Peng N, Dai Y, Michael Wyss J, Townes T, Patel RP. Antioxidant functions for the hemoglobin β93 cysteine residue in erythrocytes and in the vascular compartment in vivo. Free Radic Biol Med 2013; 55:119-29. [PMID: 23159546 PMCID: PMC3821075 DOI: 10.1016/j.freeradbiomed.2012.11.003] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/03/2012] [Revised: 09/29/2012] [Accepted: 11/06/2012] [Indexed: 12/25/2022]
Abstract
The β93 cysteine (β93Cys) residue of hemoglobin is conserved in vertebrates but its function in the red blood cell (RBC) remains unclear. Because this residue is present at concentrations more than 2 orders of magnitude higher than enzymatic components of the RBC antioxidant network, a role in the scavenging of reactive species was hypothesized. Initial studies utilizing mice that express human hemoglobin with either Cys (B93C) or Ala (B93A) at the β93 position demonstrated that loss of the β93Cys did not affect activities nor expression of established components of the RBC antioxidant network (catalase, superoxide dismutase, peroxiredoxin-2, glutathione peroxidase, GSH:GSSG ratios). Interestingly, exogenous addition to RBCs of reactive species that are involved in vascular inflammation demonstrated a role for the β93Cys in hydrogen peroxide and chloramine consumption. To simulate oxidative stress and inflammation in vivo, mice were challenged with lipopolysaccharide (LPS). Notably, LPS induced a greater degree of hypotension and lung injury in B93A versus B93C mice, which was associated with greater formation of RBC reactive species and accumulation of DMPO-reactive epitopes in the lung. These data suggest that the β93Cys is an important effector within the RBC antioxidant network, contributing to the modulation of tissue injury during vascular inflammation.
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Affiliation(s)
| | - Chiao-Wang Sun
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham
| | | | | | | | - Balu K. Chacko
- Department of Pathology, University of Alabama at Birmingham
| | - Ning Peng
- Department of Pediatrics and Cell Biology, University of Alabama at Birmingham
| | - Yanying Dai
- Department of Pediatrics and Cell Biology, University of Alabama at Birmingham
| | - J. Michael Wyss
- Department of Pediatrics and Cell Biology, University of Alabama at Birmingham
| | - Tim Townes
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham
| | - Rakesh P. Patel
- Department of Pathology, University of Alabama at Birmingham
- Center for Free Radical Biology, University of Alabama at Birmingham
- Corresponding Author: Rakesh P Patel, PhD, Department of Pathology, University of Alabama at Birmingham, 901 19 street south, BMR-2, room 532, Birmingham, AL 35294, , Tel: 205 975 9225
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Potential implication of the chemical properties and bioactivity of nitrone spin traps for therapeutics. Future Med Chem 2012; 4:1171-207. [PMID: 22709256 DOI: 10.4155/fmc.12.74] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Nitrone therapeutics has been employed in the treatment of oxidative stress-related diseases such as neurodegeneration, cardiovascular disease and cancer. The nitrone-based compound NXY-059, which is the first drug to reach clinical trials for the treatment of acute ischemic stroke, has provided promise for the development of more robust pharmacological agents. However, the specific mechanism of nitrone bioactivity remains unclear. In this review, we present a variety of nitrone chemistry and biological activity that could be implicated for the nitrone's pharmacological activity. The chemistries of spin trapping and spin adduct reveal insights on the possible roles of nitrones for altering cellular redox status through radical scavenging or nitric oxide donation, and their biological effects are presented. An interdisciplinary approach towards the development of novel synthetic antioxidants with improved pharmacological properties encompassing theoretical, synthetic, biochemical and in vitro/in vivo studies is covered.
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Davis MF, Zhou L, Ehrenshaft M, Ranguelova K, Gunawardena HP, Chen X, Bonini M, Mason RP, Campbell SL. Detection of Ras GTPase protein radicals through immuno-spin trapping. Free Radic Biol Med 2012; 53:1339-45. [PMID: 22819983 PMCID: PMC3549333 DOI: 10.1016/j.freeradbiomed.2012.07.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2012] [Revised: 06/27/2012] [Accepted: 07/10/2012] [Indexed: 01/05/2023]
Abstract
Over the past decade immuno-spin trapping (IST) has been used to detect and identify protein radical sites in numerous heme and metalloproteins. To date, however, the technique has had little application toward nonmetalloproteins. In this study, we demonstrate the successful application of IST in a system free of transition metals and present the first conclusive evidence of (•)NO-mediated protein radical formation in the HRas GTPase. HRas is a nonmetalloprotein that plays a critical role in regulating cell-growth control. Protein radical formation in Ras GTPases has long been suspected of initiating premature release of bound guanine nucleotide. This action results in altered Ras activity both in vitro and in vivo. As described herein, successful application of IST may provide a means for detecting and identifying radical-mediated Ras activation in many different cancers and disease states in which Ras GTPases play an important role.
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Affiliation(s)
- Michael F. Davis
- Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC 27599
- Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, NC 27599
| | - Li Zhou
- Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, NC 27599
| | - Marilyn Ehrenshaft
- Laboratory of Toxicology and Pharmacology, National Institute of Environmental Health Sciences, P.O. Box 12233, MD F0-01, 111 T. W. Alexander Drive, Research Triangle Park, North Carolina 27709
| | - Kalina Ranguelova
- Laboratory of Toxicology and Pharmacology, National Institute of Environmental Health Sciences, P.O. Box 12233, MD F0-01, 111 T. W. Alexander Drive, Research Triangle Park, North Carolina 27709
| | - Harsha P. Gunawardena
- Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, NC 27599
| | - Xian Chen
- Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, NC 27599
| | - Marcelo Bonini
- UIC Section of Cardiology, University of Illinois at Chicago, Chicago IL 60612
| | - Ronald P. Mason
- Laboratory of Toxicology and Pharmacology, National Institute of Environmental Health Sciences, P.O. Box 12233, MD F0-01, 111 T. W. Alexander Drive, Research Triangle Park, North Carolina 27709
| | - Sharon L. Campbell
- Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC 27599
- Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, NC 27599
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32
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Dogan S, Ozlem Elpek G, Kirimlioglu Konuk E, Demir N, Aslan M. Measurement of intracellular biomolecular oxidation in liver ischemia-reperfusion injury via immuno-spin trapping. Free Radic Biol Med 2012; 53:406-14. [PMID: 22634144 DOI: 10.1016/j.freeradbiomed.2012.05.028] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/18/2012] [Revised: 05/08/2012] [Accepted: 05/15/2012] [Indexed: 12/29/2022]
Abstract
Hepatic ischemia-reperfusion (I/R) can lead to liver failure in association with remote organ damage, both of which have significant rates of morbidity and mortality. In this study, novel spin trapping and histopathological techniques have been used to investigate in vivo free radical formation in a rat model of warm liver I/R injury. 5,5-Dimethyl-1-pyrroline N-oxide (DMPO) was administered to rats via intraperitoneal injection at a single dose of 1.5g of pure DMPO/kg body wt 2h before the initiation of liver ischemia. Blood vessels supplying the median and left lateral hepatic lobes were occluded with an arterial clamp for 60min, followed by 60min reperfusion. The effects of DMPO on I/R injury were evaluated by assessing the hepatic ultrastructure via transmission electron microscopy and by histopathological scoring. Immunoelectron microscopy was performed to determine the cellular localization of DMPO nitrone adducts. Levels of nitrone adducts were also measured to determine in situ scavenging of protein and DNA radicals. Total histopathological scoring of cellular damage was significantly decreased in hepatic I/R injury after DMPO treatment. DMPO treatment significantly decreased the hepatic conversion of xanthine oxidase and 4-hydroxynonenal formation in I/R injury compared to the untreated I/R group. The distribution of gold-nanoparticle-labeled DMPO nitrone adducts was observed in mitochondria, cytoplasm, and nucleus of hepatocytes. The formation of protein- and DNA-nitrone adducts was increased in DMPO-treated I/R livers compared to DMPO controls, indicating increased in situ protein and DNA radical formation and scavenging by DMPO. These results suggest that DMPO reduces I/R damage via protection against oxidative injury.
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Affiliation(s)
- Serdar Dogan
- Department of Medical Biochemistry, Akdeniz University Medical School, Antalya, Turkey
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Petruk AA, Bartesaghi S, Trujillo M, Estrin DA, Murgida D, Kalyanaraman B, Marti MA, Radi R. Molecular basis of intramolecular electron transfer in proteins during radical-mediated oxidations: computer simulation studies in model tyrosine-cysteine peptides in solution. Arch Biochem Biophys 2012; 525:82-91. [PMID: 22640642 DOI: 10.1016/j.abb.2012.05.012] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2012] [Revised: 05/05/2012] [Accepted: 05/20/2012] [Indexed: 11/15/2022]
Abstract
Experimental studies in hemeproteins and model Tyr/Cys-containing peptides exposed to oxidizing and nitrating species suggest that intramolecular electron transfer (IET) between tyrosyl radicals (Tyr-O(·)) and Cys residues controls oxidative modification yields. The molecular basis of this IET process is not sufficiently understood with structural atomic detail. Herein, we analyzed using molecular dynamics and quantum mechanics-based computational calculations, mechanistic possibilities for the radical transfer reaction in Tyr/Cys-containing peptides in solution and correlated them with existing experimental data. Our results support that Tyr-O(·) to Cys radical transfer is mediated by an acid/base equilibrium that involves deprotonation of Cys to form the thiolate, followed by a likely rate-limiting transfer process to yield cysteinyl radical and a Tyr phenolate; proton uptake by Tyr completes the reaction. Both, the pKa values of the Tyr phenol and Cys thiol groups and the energetic and kinetics of the reversible IET are revealed as key physico-chemical factors. The proposed mechanism constitutes a case of sequential, acid/base equilibrium-dependent and solvent-mediated, proton-coupled electron transfer and explains the dependency of oxidative yields in Tyr/Cys peptides as a function of the number of alanine spacers. These findings contribute to explain oxidative modifications in proteins that contain sequence and/or spatially close Tyr-Cys residues.
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Affiliation(s)
- Ariel A Petruk
- Instituto Superior de Investigaciones Biológicas (CONICET-UNT), Chacabuco 461, S.M. de Tucumán, Tucumán, T4000CAN, Argentina
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34
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Franzen S, Thompson MK, Ghiladi RA. The dehaloperoxidase paradox. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2012; 1824:578-88. [DOI: 10.1016/j.bbapap.2011.12.008] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2011] [Revised: 12/20/2011] [Accepted: 12/23/2011] [Indexed: 12/01/2022]
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35
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Bhattacharjee S, Chatterjee S, Jiang J, Sinha BK, Mason RP. Detection and imaging of the free radical DNA in cells--site-specific radical formation induced by Fenton chemistry and its repair in cellular DNA as seen by electron spin resonance, immuno-spin trapping and confocal microscopy. Nucleic Acids Res 2012; 40:5477-86. [PMID: 22387463 PMCID: PMC3384307 DOI: 10.1093/nar/gks180] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Oxidative stress-related damage to the DNA macromolecule produces lesions that are implicated in various diseases. To understand damage to DNA, it is important to study the free radical reactions causing the damage. Measurement of DNA damage has been a matter of debate as most of the available methods measure the end product of a sequence of events and provide limited information on the initial free radical formation. We report a measurement of free radical damage in DNA induced by a Cu(II)-H2O2 oxidizing system using immuno-spin trapping supplemented with electron paramagnetic resonance. In this investigation, the short-lived radical generated is trapped by the spin trap 5,5-dimethyl-1-pyrroline N-oxide (DMPO) immediately upon formation. The DMPO adduct formed is initially electron paramagnetic resonance active, but is subsequently oxidized to the stable nitrone adduct, which can be detected and visualized by immuno-spin trapping and has the potential to be further characterized by other analytical techniques. The radical was found to be located on the 2′-deoxyadenosine (dAdo) moiety of DNA. The nitrone adduct was repaired on a time scale consistent with DNA repair. In vivo experiments for the purpose of detecting DMPO–DNA nitrone adducts should be conducted over a range of time in order to avoid missing adducts due to the repair processes.
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Affiliation(s)
- Suchandra Bhattacharjee
- Laboratory of Toxicology and Chemistry, National Institute of Environmental Health Sciences, NIH, Research Triangle Park, NC 27709, USA.
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36
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Spasojević I. Free radicals and antioxidants at a glance using EPR spectroscopy. Crit Rev Clin Lab Sci 2011; 48:114-42. [DOI: 10.3109/10408363.2011.591772] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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37
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Davis MF, Vigil D, Campbell SL. Regulation of Ras proteins by reactive nitrogen species. Free Radic Biol Med 2011; 51:565-75. [PMID: 21616138 PMCID: PMC3549334 DOI: 10.1016/j.freeradbiomed.2011.05.003] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2011] [Revised: 04/11/2011] [Accepted: 05/03/2011] [Indexed: 11/28/2022]
Abstract
Ras GTPases have been a subject of intense investigation since the early 1980s, when single point mutations in Ras were shown to cause deregulated cell growth control. Subsequently, Ras was identified as the most prevalent oncogene found in human cancer. Ras proteins regulate a host of pathways involved in cell growth, differentiation, and apoptosis by cycling between inactive GDP-bound and active GTP-bound states. Regulation of Ras activity is controlled by cellular factors that alter guanine nucleotide cycling. Oncogenic mutations prevent protein regulatory factors from down-regulating Ras activity, thereby maintaining Ras in a chronically activated state. The central dogma in the field is that protein modulatory factors are the primary regulators of Ras activity. Since the mid-1990s, however, evidence has accumulated that small molecule reactive nitrogen species (RNS) can also influence Ras guanine nucleotide cycling. Herein, we review the basic chemistry behind RNS formation and discuss the mechanism through which various RNS enhance nucleotide exchange in Ras proteins. In addition, we present studies that demonstrate the physiological relevance of RNS-mediated Ras activation within the context of immune system function, brain function, and cancer development. We also highlight future directions and experimental methods that may enhance our ability to detect RNS-mediated activation in cell cultures and in vivo. The development of such methods may ultimately pave new directions for detecting and elucidating how Ras proteins are regulated by redox species, as well as for targeting redox-activated Ras in cancer and other disease states.
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Affiliation(s)
- Michael F. Davis
- Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC 27599
- Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, NC 27599
| | - Dom Vigil
- Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC 27599
- Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, NC 27599
| | - Sharon L. Campbell
- Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC 27599
- Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, NC 27599
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38
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Romano CA, Sontz PA, Barton JK. Mutants of the base excision repair glycosylase, endonuclease III: DNA charge transport as a first step in lesion detection. Biochemistry 2011; 50:6133-45. [PMID: 21651304 DOI: 10.1021/bi2003179] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Endonuclease III (EndoIII) is a base excision repair glycosylase that targets damaged pyrimidines and contains a [4Fe-4S] cluster. We have proposed a model where BER proteins that contain redox-active [4Fe-4S] clusters utilize DNA charge transport (CT) as a first step in the detection of DNA lesions. Here, several mutants of EndoIII were prepared to probe their efficiency of DNA/protein charge transport. Cyclic voltammetry experiments on DNA-modified electrodes show that aromatic residues F30, Y55, Y75, and Y82 help mediate charge transport between DNA and the [4Fe-4S] cluster. On the basis of circular dichroism studies to measure protein stability, mutations at residues W178 and Y185 are found to destabilize the protein; these residues may function to protect the [4Fe-4S] cluster. Atomic force microscopy studies furthermore reveal a correlation in the ability of mutants to carry out protein/DNA CT and their ability to relocalize onto DNA strands containing a single base mismatch; EndoIII mutants that are defective in carrying out DNA/protein CT do not redistribute onto mismatch-containing strands, consistent with our model. These results demonstrate a link between the ability of the repair protein to carry out DNA CT and its ability to relocalize near lesions, thus pointing to DNA CT as a key first step in the detection of base damage in the genome.
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Affiliation(s)
- Christine A Romano
- Division of Chemistry and Chemical Engineering, California Institute of Technolog, Pasadena, California 91125, USA
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39
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Bhattacharjee S, Deterding LJ, Chatterjee S, Jiang J, Ehrenshaft M, Lardinois O, Ramirez DC, Tomer KB, Mason RP. Site-specific radical formation in DNA induced by Cu(II)-H₂O₂ oxidizing system, using ESR, immuno-spin trapping, LC-MS, and MS/MS. Free Radic Biol Med 2011; 50:1536-45. [PMID: 21382477 PMCID: PMC3100166 DOI: 10.1016/j.freeradbiomed.2011.02.034] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/28/2011] [Revised: 02/23/2011] [Accepted: 02/25/2011] [Indexed: 11/29/2022]
Abstract
Oxidative stress-related damage to the DNA macromolecule produces a multitude of lesions that are implicated in mutagenesis, carcinogenesis, reproductive cell death, and aging. Many of these lesions have been studied and characterized by various techniques. Of the techniques that are available, the comet assay, HPLC-EC, GC-MS, HPLC-MS, and especially HPLC-MS/MS remain the most widely used and have provided invaluable information on these lesions. However, accurate measurement of DNA damage has been a matter of debate. In particular, there have been reports of artifactual oxidation leading to erroneously high damage estimates. Further, most of these techniques measure the end product of a sequence of events and thus provide only limited information on the initial radical mechanism. We report here a qualitative measurement of DNA damage induced by a Cu(II)-H₂O₂ oxidizing system using immuno-spin trapping (IST) with electron paramagnetic resonance (EPR), MS, and MS/MS. The radical generated is trapped by DMPO immediately upon formation. The DMPO adduct formed is initially EPR active but subsequently is oxidized to the stable nitrone, which can then be detected by IST and further characterized by MS and MS/MS.
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Affiliation(s)
- Suchandra Bhattacharjee
- Laboratory of Toxicology and Pharmacology, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709, USA.
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40
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Stoyanovsky DA, Maeda A, Atkins JL, Kagan VE. Assessments of Thiyl Radicals in Biosystems: Difficulties and New Applications. Anal Chem 2011; 83:6432-8. [DOI: 10.1021/ac200418s] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
| | | | - James L. Atkins
- Walter Reed Army Institute of Research, Silver Spring, Maryland 20910, United States
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41
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Foster MW. Methodologies for the characterization, identification and quantification of S-nitrosylated proteins. Biochim Biophys Acta Gen Subj 2011; 1820:675-83. [PMID: 21440604 DOI: 10.1016/j.bbagen.2011.03.013] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2011] [Revised: 03/06/2011] [Accepted: 03/21/2011] [Indexed: 11/26/2022]
Abstract
BACKGROUND Protein S-nitrosylation plays a central role in signal transduction by nitric oxide (NO), and aberrant S-nitrosylation of specific proteins is increasingly implicated in disease. SCOPE OF REVIEW Here, methodologies for the characterization, identification and quantification of SNO-proteins are reviewed, focusing on techniques suitable for the structural characterization and absolute quantification of isolated SNO-proteins, the identification and relative quantification of SNO-proteins from complex mixtures as well as the mass spectrometry-based identification and relative quantification of sites of S-nitrosylation (SNO-sites) in proteins. MAJOR CONCLUSIONS Structural characterization of SNO-proteins by X-ray crystallography is increasingly being utilized to understand both the relationships between protein structure and Cys thiol reactivity as well as the consequences of S-nitrosylation on protein structure and function. New methods for the proteomic identification and quantification of SNO-proteins and SNO-sites have greatly impacted the ability to study protein S-nitrosylation in complex biological systems. GENERAL SIGNIFICANCE The ability to identify and quantify SNO-proteins has long been rate-determining for scientific advances in the field of protein S-nitrosylation. Therefore, it is critical that investigators in the field have a good understand the utility and limitations of modern analytical techniques for SNO-protein analysis. This article is part of a Special Issue entitled: Regulation of cellular processes by S-nitrosylation.
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Affiliation(s)
- Matthew W Foster
- Division of Pulmonary, Allergy and Critical Care Medicine, Duke University Medical Center, Durham, NC 27710, USA.
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42
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Nagao S, Asami O, Yasui H, Hirota S. Efficient reduction of Cys110 thiyl radical by glutathione in human myoglobin. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2011; 1814:480-6. [DOI: 10.1016/j.bbapap.2011.01.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2010] [Revised: 12/28/2010] [Accepted: 01/13/2011] [Indexed: 11/16/2022]
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43
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Influence of amino acid relative position on the oxidative modification of histidine and glycine peptides. Anal Bioanal Chem 2011; 399:2779-94. [DOI: 10.1007/s00216-011-4668-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2010] [Revised: 12/05/2010] [Accepted: 01/05/2011] [Indexed: 10/18/2022]
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44
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Pimenova T, Pereira CP, Gehrig P, Buehler PW, Schaer DJ, Zenobi R. Quantitative mass spectrometry defines an oxidative hotspot in hemoglobin that is specifically protected by haptoglobin. J Proteome Res 2010; 9:4061-70. [PMID: 20568812 DOI: 10.1021/pr100252e] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The reaction of hemoglobin (Hb) with hydrogen peroxide (H(2)O(2)) results in free radicals generated at the heme iron, followed by radical transfer to the porphyrin/globin. In the present work, we employed isobaric tagging for relative and absolute quantification (iTRAQ) and a LC-MALDI-MS/MS-based proteomic approach to identify the extent of oxidative changes within tetrameric Hb and dimeric Hb-haptoglobin (Hb-Hp) complexes. Extensive oxidative modifications were found to be restricted to peptides containing alphaTyr42, betaTyr145, and betaCys93. The protein region composed of these peptides appears to define an area of oxidative activity within the Hb tetramer that extends across the critical alpha1beta2/alpha2beta1 interface. Extensive oxidative modifications occurring at betaCys93 indicate that this surface amino acid is an important end point for free radical induced protein oxidation within Hb. Conversely when Hp 1-1 or 2-2 was complexed with dissociable Hb, oxidative changes in Hp complexed dimeric Hb were prevented. This protection was not observed in a stabilized tetrameric Hb, which displays a weak binding affinity for Hp. Therefore, dimerization of Hb and Hp binding may interfere with free radical translocation and play an important role in the overall antioxidant mechanism of Hp. Interestingly, the prevention of peroxide induced Hb amino acid oxidation in purified Hb-Hp1-1 and Hb-Hp2-2 was found to be equal, indicating a phenotype independent specificity in the process of oxidative protection. Taken together, these data suggest differences in oxidative modifications resulting from peroxide induced heme emanated free radical distribution in tetrameric compared to Hp1-1/Hp2-2 stabilized dimeric Hb.
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Affiliation(s)
- Tatiana Pimenova
- Department of Chemistry and Applied Biosciences, ETH Zurich, Switzerland
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45
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Ranguelova K, Bonini MG, Mason RP. (Bi)sulfite oxidation by copper, zinc-superoxide dismutase: Sulfite-derived, radical-initiated protein radical formation. ENVIRONMENTAL HEALTH PERSPECTIVES 2010; 118:970-5. [PMID: 20348042 PMCID: PMC2920917 DOI: 10.1289/ehp.0901533] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2009] [Accepted: 03/26/2010] [Indexed: 05/12/2023]
Abstract
BACKGROUND Sulfur dioxide, formed during the combustion of fossil fuels, is a major air pollutant near large cities. Its two ionized forms in aqueous solution, sulfite and (bi)sulfite, are widely used as preservatives and antioxidants to prevent food and beverage spoilage. (Bi)sulfite can be oxidized by peroxidases to form the very reactive sulfur trioxide anion radical (*SO(3)-). This free radical further reacts with oxygen to form the peroxymonosulfate anion radical (-O(3)SOO*) and sulfate anion radical (SO(4)*-). OBJECTIVE To explore the critical role of these radical intermediates in further oxidizing biomolecules, we examined the ability of copper,zinc-superoxide dismutase (Cu,Zn-SOD) to initiate this radical chain reaction, using human serum albumin (HSA) as a model target. METHODS We used electron paramagnetic resonance, optical spectroscopy, oxygen uptake, and immuno-spin trapping to study the protein oxidations driven by sulfite-derived radicals. RESULTS We found that when Cu,Zn-SOD reacted with (bi)sulfite, *SO(3)- was produced, with the concomitant reduction of SOD-Cu(II) to SOD-Cu(I). Further, we demonstrated that sulfite oxidation mediated by Cu,Zn-SOD induced the formation of radical-derived 5,5-dimethyl-1-pyrroline N-oxide (DMPO) spin-trapped HSA radicals. CONCLUSIONS The present study suggests that protein oxidative damage resulting from (bi)sulfite oxidation promoted by Cu,Zn-SOD could be involved in oxidative damage and tissue injury in (bi)sulfite-exacerbated allergic reactions.
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Affiliation(s)
- Kalina Ranguelova
- Laboratory of Pharmacology, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, North Carolina 27709, USA.
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46
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Davis MF, Bobay BG, Franzen S. Determination of separate inhibitor and substrate binding sites in the dehaloperoxidase-hemoglobin from Amphitrite ornata. Biochemistry 2010; 49:1199-206. [PMID: 20067301 DOI: 10.1021/bi9018576] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Dehaloperoxidase-hemoglobin (DHP A) is a dual function protein found in the terrebellid polychaete Amphitrite ornata. A. ornata is an annelid, which inhabits estuary mudflats with other polychaetes that secrete a range of toxic brominated phenols. DHP A is capable of binding and oxidatively dehalogenating some of these compounds. DHP A possesses the ability to bind halophenols in a distinct, internal distal binding pocket. Since its discovery, the distal binding pocket has been reported as the sole binding location for halophenols; however, data herein suggest a distinction between inhibitor (monohalogenated phenol) and substrate (trihalogenated phenol) binding locations. Backbone (13)Calpha, (13)Cbeta, carbonyl (13)C, amide (1)H, and amide (15)N resonance assignments have been made, and various halophenols were titrated into the protein. (1)H-(15)N HSQC experiments were collected at stoichiometric intervals during each titration, and binding locations specific for mono- and trihalogenated phenols have been identified. Titration of monohalogenated phenol induced primary changes around the distal binding pocket, while introduction of trihalogenated phenols created alterations of the distal histidine and the local area surrounding W120, a structural region that corresponds to a possible dimer interface region recently observed in X-ray crystal structures of DHP A.
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Affiliation(s)
- Michael F Davis
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27606, USA
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Seyedsayamdost MR, Argirević T, Minnihan EC, Stubbe J, Bennati M. Structural examination of the transient 3-aminotyrosyl radical on the PCET pathway of E. coli ribonucleotide reductase by multifrequency EPR spectroscopy. J Am Chem Soc 2010; 131:15729-38. [PMID: 19821570 PMCID: PMC4703294 DOI: 10.1021/ja903879w] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
E. coli ribonucleotide reductase (RNR) catalyzes the conversion of nucleotides to deoxynucleotides, a process that requires long-range radical transfer over 35 A from a tyrosyl radical (Y(122)*) within the beta2 subunit to a cysteine residue (C(439)) within the alpha2 subunit. The radical transfer step is proposed to occur by proton-coupled electron transfer via a specific pathway consisting of Y(122) --> W(48) --> Y(356) in beta2, across the subunit interface to Y(731) --> Y(730) --> C(439) in alpha2. Using the suppressor tRNA/aminoacyl-tRNA synthetase (RS) methodology, 3-aminotyrosine has been incorporated into position 730 in alpha2. Incubation of this mutant with beta2, substrate, and allosteric effector resulted in loss of the Y(122)* and formation of a new radical, previously proposed to be a 3-aminotyrosyl radical (NH(2)Y*). In the current study [(15)N]- and [(14)N]-NH(2)Y(730)* have been generated in H(2)O and D(2)O and characterized by continuous wave 9 GHz EPR and pulsed EPR spectroscopies at 9, 94, and 180 GHz. The data give insight into the electronic and molecular structure of NH(2)Y(730)*. The g tensor (g(x) = 2.0052, g(y) = 2.0042, g(z) = 2.0022), the orientation of the beta-protons, the hybridization of the amine nitrogen, and the orientation of the amino protons relative to the plane of the aromatic ring were determined. The hyperfine coupling constants and geometry of the NH(2) moiety are consistent with an intramolecular hydrogen bond within NH(2)Y(730)*. This analysis is an essential first step in using the detailed structure of NH(2)Y(730)* to formulate a model for a PCET mechanism within alpha2 and for use of NH(2)Y in other systems where transient Y*s participate in catalysis.
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Affiliation(s)
- Mohammad R Seyedsayamdost
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139-4307, USA
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48
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Minnihan EC, Seyedsayamdost MR, Stubbe J. Use of 3-aminotyrosine to examine the pathway dependence of radical propagation in Escherichia coli ribonucleotide reductase. Biochemistry 2010; 48:12125-32. [PMID: 19916558 DOI: 10.1021/bi901439w] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Escherichia coli ribonucleotide reductase (RNR), an alpha2beta2 complex, catalyzes the conversion of nucleoside 5'-diphosphate substrates (S) to 2'-deoxynucleoside 5'-diphosphates. alpha2 houses the active site for nucleotide reduction and the binding sites for allosteric effectors (E). beta2 contains the essential diferric tyrosyl radical (Y(122)(*)) cofactor which, in the presence of S and E, oxidizes C(439) in alpha to a thiyl radical, C(439)(*), to initiate nucleotide reduction. This oxidation occurs over 35 A and is proposed to involve a specific pathway: Y(122)(*) --> W(48) --> Y(356) in beta2 to Y(731) --> Y(730) --> C(439) in alpha2. 3-Aminotyrosine (NH(2)Y) has been site-specifically incorporated at residues 730 and 731, and formation of the aminotyrosyl radical (NH(2)Y(*)) has been examined by stopped-flow (SF) UV-vis and EPR spectroscopies. To examine the pathway dependence of radical propagation, the double mutant complexes Y(356)F-beta2:Y(731)NH(2)Y-alpha2, Y(356)F-beta2:Y(730)NH(2)Y-alpha2, and wt-beta2:Y(731)F/Y(730)NH(2)Y-alpha2, in which the nonoxidizable F acts as a pathway block, were studied by SF and EPR spectroscopies. In all cases, no NH(2)Y(*) was detected. To study off-pathway oxidation, Y(413), located 5 A from Y(730) and Y(731) but not implicated in long-range oxidation, was examined. Evidence for NH(2)Y(413)(*) was sought in three complexes: wt-beta2:Y(413)NH(2)Y-alpha2 (a), wt-beta2:Y(731)F/Y(413)NH(2)Y-alpha2 (b), and Y(356)F-beta2:Y(413)NH(2)Y-alpha2 (c). With (a), NH(2)Y(*) was formed with a rate constant that was 25-30% and an amplitude that was 25% of that observed for its formation at residues 731 and 730. With (b), the rate constant for NH(2)Y(*) formation was 0.2-0.3% of that observed at 731 and 730, and with (c), no NH(2)Y(*) was observed. These studies suggest the evolution of an optimized pathway of conserved Ys in the oxidation of C(439).
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Affiliation(s)
- Ellen C Minnihan
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge,Massachusetts 02139-4307, USA
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Trujillo M, Alvarez B, Souza JM, Romero N, Castro L, Thomson L, Radi R. Mechanisms and Biological Consequences of Peroxynitrite-Dependent Protein Oxidation and Nitration. Nitric Oxide 2010. [DOI: 10.1016/b978-0-12-373866-0.00003-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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Hawkins CL, Morgan PE, Davies MJ. Quantification of protein modification by oxidants. Free Radic Biol Med 2009; 46:965-88. [PMID: 19439229 DOI: 10.1016/j.freeradbiomed.2009.01.007] [Citation(s) in RCA: 338] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2008] [Revised: 01/12/2009] [Accepted: 01/12/2009] [Indexed: 12/19/2022]
Abstract
Proteins are major targets for oxidative damage due to their abundance and rapid rates of reaction with a wide range of radicals and excited state species, such as singlet oxygen. Exposure of proteins to these oxidants results in loss of the parent amino acid residue, formation of unstable intermediates, and the generation of stable products. Each of these events can be used, to a greater or lesser extent, to quantify damage to proteins. In this review the advantages and disadvantages of a number of these approaches are discussed, with an emphasis on methods that yield absolute quantitative data on the extent of protein modification. Detailed methods sheets are provided for many of these techniques.
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