1
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Guberman-Pfeffer MJ. Assessing Thermal Response of Redox Conduction for Anti-Arrhenius Kinetics in a Microbial Cytochrome Nanowire. J Phys Chem B 2022; 126:10083-10097. [PMID: 36417757 PMCID: PMC9743091 DOI: 10.1021/acs.jpcb.2c06822] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
A micrometers-long helical homopolymer of the outer-membrane cytochrome type S (OmcS) from Geobacter sulfurreducens is proposed to transport electrons to extracellular acceptors in an ancient respiratory strategy of biogeochemical and technological significance. OmcS surprisingly exhibits higher conductivity upon cooling (anti-Arrhenius kinetics), an effect previously attributed to H-bond restructuring and heme redox potential shifts. Herein, the temperature sensitivity of redox conductivity is more thoroughly examined with conventional and constant-redox and -pH molecular dynamics and quantum mechanics/molecular mechanics. A 30 K drop in temperature constituted a weak perturbation to electron transfer energetics, changing electronic couplings (⟨Hmn⟩), reaction free energies (ΔGmn), reorganization energies (λmn), and activation energies (Ea) by at most |0.002|, |0.050|, |0.120|, and |0.045| eV, respectively. Changes in ΔGmn reflected -0.07 ± 0.03 V shifts in redox potentials that were caused in roughly equal measure by altered electrostatic interactions with the solvent and protein. Changes in intraprotein H-bonding reproduced the earlier observations. Single-particle diffusion and multiparticle steady-state flux models, parametrized with Marcus theory rates, showed that biologically relevant incoherent hopping cannot qualitatively or quantitatively describe electrical conductivity measured by atomic force microscopy in filamentous OmcS. The discrepancy is attributed to differences between solution-phase simulations and solid-state measurements and the need to model intra- and intermolecular vibrations explicitly.
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Affiliation(s)
- Matthew J. Guberman-Pfeffer
- Department
of Molecular Biophysics and Biochemistry, Yale University, 333 Cedar St., New Haven, Connecticut06510, United States,Microbial
Sciences Institute, Yale University, 840 West Campus Drive, West Haven, Connecticut06516, United States,
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2
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Dutta A, Tapio K, Suma A, Mostafa A, Kanehira Y, Carnevale V, Bussi G, Bald I. Molecular states and spin crossover of hemin studied by DNA origami enabled single-molecule surface-enhanced Raman scattering. NANOSCALE 2022; 14:16467-16478. [PMID: 36305892 PMCID: PMC9671141 DOI: 10.1039/d2nr03664a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Accepted: 10/07/2022] [Indexed: 06/16/2023]
Abstract
The study of biologically relevant molecules and their interaction with external stimuli on a single molecular scale is of high importance due to the availability of distributed rather than averaged information. Surface enhanced Raman scattering (SERS) provides direct chemical information, but is rather challenging on the single molecule (SM) level, where it is often assumed to require a direct contact of analyte molecules with the metal surface. Here, we detect and investigate the molecular states of single hemin by SM-SERS. A DNA aptamer based G-quadruplex mediated recognition of hemin directs its placement in the SERS hot-spot of a DNA Origami Nanofork Antenna (DONA). The configuration of the DONA structure allows the molecule to be trapped at the plasmonic hot-spot preferentially in no-contact configuration with the metal surface. Owing to high field enhancement at the plasmonic hot spot, the detection of a single folded G-quadruplex becomes possible. For the first time, we present a systematic study by SM-SERS where most hemin molecule adopt a high spin and oxidation state (III) that showed state crossover to low spin upon strong-field-ligand binding. The present study therefore, provides a platform for studying biologically relevant molecules and their properties at SM sensitivity along with demonstrating a conceptual advancement towards successful monitoring of single molecular chemical interaction using DNA aptamers.
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Affiliation(s)
- Anushree Dutta
- Institute of Chemistry, Physical Chemistry, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476, Potsdam, Germany.
| | - Kosti Tapio
- Institute of Chemistry, Physical Chemistry, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476, Potsdam, Germany.
| | - Antonio Suma
- Dipartimento di Fisica, Università degli Studi di Bari, and INFN, Sezione di Bari, via Amendola 173, 70126 Bari, Italy
| | - Amr Mostafa
- Institute of Chemistry, Physical Chemistry, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476, Potsdam, Germany.
| | - Yuya Kanehira
- Institute of Chemistry, Physical Chemistry, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476, Potsdam, Germany.
| | - Vincenzo Carnevale
- Institute for Computational Molecular Science, Temple University, Philadelphia, PA 19122, USA
| | - Giovanni Bussi
- Scuola Internazionale Superiore di Studi Avanzati, Via Bonomea 265, Trieste 34136, Italy
| | - Ilko Bald
- Institute of Chemistry, Physical Chemistry, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476, Potsdam, Germany.
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3
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Gonzaga de França Lopes L, Gouveia Júnior FS, Karine Medeiros Holanda A, Maria Moreira de Carvalho I, Longhinotti E, Paulo TF, Abreu DS, Bernhardt PV, Gilles-Gonzalez MA, Cirino Nogueira Diógenes I, Henrique Silva Sousa E. Bioinorganic systems responsive to the diatomic gases O2, NO, and CO: From biological sensors to therapy. Coord Chem Rev 2021. [DOI: 10.1016/j.ccr.2021.214096] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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4
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Di Rocco G, Battistuzzi G, Borsari M, Bortolotti CA, Ranieri A, Sola M. The enthalpic and entropic terms of the reduction potential of metalloproteins: Determinants and interplay. Coord Chem Rev 2021. [DOI: 10.1016/j.ccr.2021.214071] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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5
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Schachinger F, Chang H, Scheiblbrandner S, Ludwig R. Amperometric Biosensors Based on Direct Electron Transfer Enzymes. Molecules 2021; 26:molecules26154525. [PMID: 34361678 PMCID: PMC8348568 DOI: 10.3390/molecules26154525] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 07/19/2021] [Accepted: 07/23/2021] [Indexed: 11/16/2022] Open
Abstract
The accurate determination of analyte concentrations with selective, fast, and robust methods is the key for process control, product analysis, environmental compliance, and medical applications. Enzyme-based biosensors meet these requirements to a high degree and can be operated with simple, cost efficient, and easy to use devices. This review focuses on enzymes capable of direct electron transfer (DET) to electrodes and also the electrode materials which can enable or enhance the DET type bioelectrocatalysis. It presents amperometric biosensors for the quantification of important medical, technical, and environmental analytes and it carves out the requirements for enzymes and electrode materials in DET-based third generation biosensors. This review critically surveys enzymes and biosensors for which DET has been reported. Single- or multi-cofactor enzymes featuring copper centers, hemes, FAD, FMN, or PQQ as prosthetic groups as well as fusion enzymes are presented. Nanomaterials, nanostructured electrodes, chemical surface modifications, and protein immobilization strategies are reviewed for their ability to support direct electrochemistry of enzymes. The combination of both biosensor elements-enzymes and electrodes-is evaluated by comparison of substrate specificity, current density, sensitivity, and the range of detection.
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6
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Roos G, Harvey JN. Histidine versus Cysteine-Bearing Heme-Dependent Halogen Peroxidases: Parallels and Differences for Cl - Oxidation. J Phys Chem B 2021; 125:74-85. [PMID: 33350832 DOI: 10.1021/acs.jpcb.0c09409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The homodimeric myeloperoxidase (MPO) features a histidine as a proximal ligand and a sulfonium linkage covalently attaching the heme porphyrin ring to the protein. MPO is able to catalyze Cl- oxidation with about the same efficiency as chloroperoxidase at pH 7.0. In this study, we seek to explore the parallels and differences between the histidine and cysteine heme-dependent halogen peroxidases. Transition states, reaction barriers, and relevant thermodynamic properties are calculated on protein models. Together with electronic structure calculations, it gives an overview of the reaction mechanisms and of the factors that determine the selectivity between one- and two-electron paths. Conclusions point to the innate oxidizing nature of MPO with the ester and sulfonium linkages hiking up the reactivity to enable chloride oxidation. The installation of a deprotonated imidazolate as a proximal ligand does not shift the equilibrium from one- to two-electron events without influencing the chemistry of the oxidation reaction.
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Affiliation(s)
- Goedele Roos
- UGSF-Unité de Glycobiologie Structurale et Fonctionnelle, University of Lille, CNRS, UMR 8576, F-59000 Lille, France
| | - Jeremy N Harvey
- Department of Chemistry, KU Leuven, Celestijnenlaan 200F, B-3001 Leuven, Belgium
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7
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Abstract
Myeloperoxidase participates in innate immune defense mechanism through formation of microbicidal reactive oxidants and diffusible radical species. A unique activity is its ability to use chloride as a cosubstrate with hydrogen peroxide to generate chlorinating oxidants such as hypochlorous acid, a potent antimicrobial agent. However, chronic MPO activation can lead to indiscriminate protein modification causing tissue damage, and has been associated with chronic inflammatory diseases, atherosclerosis, and acute cardiovascular events. This has attracted considerable interest in the development of therapeutically useful MPO inhibitors. Today, based on the profound knowledge of structure and function of MPO and its biochemical and biophysical differences with the other homologous human peroxidases, various rational and high-throughput screening attempts were performed in developing specific irreversible and reversible inhibitors. The most prominent candidates as well as MPO inhibitors already studied in clinical trials are introduced and discussed.
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8
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Gao D, Hou L, Liu M, Li X, Zheng Y, Yin G, Wu D, Yang Y, Han P, Liang X, Dong H. Mechanisms responsible for N 2O emissions from intertidal soils of the Yangtze Estuary. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 716:137073. [PMID: 32036146 DOI: 10.1016/j.scitotenv.2020.137073] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Revised: 01/30/2020] [Accepted: 01/31/2020] [Indexed: 06/10/2023]
Abstract
Estuarine and coastal wetland ecosystems are important sources of atmospheric nitrous oxide (N2O). However, the underlying driver of emitted N2O from estuarine and coastal wetlands remains poorly understood. Here, natural-abundance isotope technique was applied to characterize the processes responsible for N2O emission from the intertidal soils of the Yangtze Estuary. Measured N2O emission rates ranged from 0.70 to 2.15 μmol m-2 h-1, with relatively high values at the upper estuarine sites. The δ15N, δ18O and SP (intramolecular 15N site preference) of emitted N2O varied from -4.5 to 6.7‰, 42.4 to 53.2‰, and 6.7 to 15.4‰, respectively. Gross N2O production and consumption rates were within the ranges of 3.16-14.34 μmol m-2 h-1 and 2.22-12.54 μmol m-2 h-1, respectively, showing a similar spatial pattern to N2O emission. N2O consumption proportion varied from 69.56 to 90.31%, which was generally lower at the upper estuarine sites. The gross production rates and consumption degree of N2O simultaneously controlled the variations in N2O emission. Bacterial denitrification was the dominant production pathway (78.22-97.36%), while hydroxylamine (NH2OH) oxidation contributed 2.64-21.78% to N2O production. Soil pH, Fe2+/Fe3+, sulfide and substrate availability were probably the main factors governing the N2O emission dynamics. Overall, these results highlight the substantial role of NH2OH oxidation and N2O consumption in N2O release in redox-dynamic soils of estuarine intertidal wetlands.
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Affiliation(s)
- Dengzhou Gao
- Key Laboratory of Geographic Information Science of the Ministry of Education, College of Geographical Sciences, East China Normal University, 500 Dongchuan Road, Shanghai 200241, China; State Key Laboratory of Estuarine and Coastal Research, East China Normal University, 3663 North Zhongshan Road, Shanghai 200062, China
| | - Lijun Hou
- State Key Laboratory of Estuarine and Coastal Research, East China Normal University, 3663 North Zhongshan Road, Shanghai 200062, China.
| | - Min Liu
- Key Laboratory of Geographic Information Science of the Ministry of Education, College of Geographical Sciences, East China Normal University, 500 Dongchuan Road, Shanghai 200241, China
| | - Xiaofei Li
- Key Laboratory for Humid Subtropical Eco-geographical Processes of the Ministry of Education, Fujian Normal University, 8 Shangsan Road, Fuzhou 350007, China
| | - Yanling Zheng
- Key Laboratory of Geographic Information Science of the Ministry of Education, College of Geographical Sciences, East China Normal University, 500 Dongchuan Road, Shanghai 200241, China; State Key Laboratory of Estuarine and Coastal Research, East China Normal University, 3663 North Zhongshan Road, Shanghai 200062, China
| | - Guoyu Yin
- Key Laboratory of Geographic Information Science of the Ministry of Education, College of Geographical Sciences, East China Normal University, 500 Dongchuan Road, Shanghai 200241, China
| | - Dianming Wu
- Key Laboratory of Geographic Information Science of the Ministry of Education, College of Geographical Sciences, East China Normal University, 500 Dongchuan Road, Shanghai 200241, China
| | - Yi Yang
- Key Laboratory of Geographic Information Science of the Ministry of Education, College of Geographical Sciences, East China Normal University, 500 Dongchuan Road, Shanghai 200241, China; State Key Laboratory of Estuarine and Coastal Research, East China Normal University, 3663 North Zhongshan Road, Shanghai 200062, China
| | - Ping Han
- Key Laboratory of Geographic Information Science of the Ministry of Education, College of Geographical Sciences, East China Normal University, 500 Dongchuan Road, Shanghai 200241, China; State Key Laboratory of Estuarine and Coastal Research, East China Normal University, 3663 North Zhongshan Road, Shanghai 200062, China
| | - Xia Liang
- Key Laboratory of Geographic Information Science of the Ministry of Education, College of Geographical Sciences, East China Normal University, 500 Dongchuan Road, Shanghai 200241, China
| | - Hongpo Dong
- Key Laboratory of Geographic Information Science of the Ministry of Education, College of Geographical Sciences, East China Normal University, 500 Dongchuan Road, Shanghai 200241, China
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9
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Chundawat NS, Pande N, Sargazi G, Gholipourmalekabadi M, Chauhan NPS. Structure-properties relationship for energy storage redox polymers: a review. JOURNAL OF POLYMER ENGINEERING 2020. [DOI: 10.1515/polyeng-2019-0395] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Abstract
Redox-active polymers among the energy storage materials (ESMs) are very attractive due to their exceptional advantages such as high stability and processability as well as their simple manufacturing. Their applications are found to useful in electric vehicle, ultraright computers, intelligent electric gadgets, mobile sensor systems, and portable intelligent clothing. They are found to be more efficient and advantageous in terms of superior processing capacity, quick loading unloading, stronger security, lengthy life cycle, versatility, adjustment to various scales, excellent fabrication process capabilities, light weight, flexible, most significantly cost efficiency, and non-toxicity in order to satisfy the requirement for the usage of these potential applications. The redox-active polymers are produced through organic synthesis, which allows the design and free modification of chemical constructions, which allow for the structure of organic compounds. The redox-active polymers can be finely tuned for the desired ESMs applications with their chemical structures and electrochemical properties. The redox-active polymers synthesis also offers the benefits of high-scale, relatively low reaction, and a low demand for energy. In this review we discussed the relationship between structural properties of different polymers for solar energy and their energy storage applications.
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Affiliation(s)
- Narendra Singh Chundawat
- Department of Chemistry , Faculty of Science , Bhupal Nobles' University , Udaipur , Rajasthan , India
| | - Nishigandh Pande
- School of Mechatronics Engineering , Symbiosis Skills & Professional University , Kiwale , Pune , Maharashtra , India
| | - Ghasem Sargazi
- Environment and Nanochemistry Department , Research Institute of Environmental Science , International Center for Science , High Technology & Environmental Science , Kerman , Iran
| | - Mazaher Gholipourmalekabadi
- Cellular and Molecular Research Centre , Iran University of Medical Sciences , Tehran , Iran
- Department of Tissue Engineering & Regenerative Medicine, Faculty of Advanced Technologies in Medicine , Iran University of Medical Sciences , Tehran , Iran
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10
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Paradisi A, Lancellotti L, Borsari M, Bellei M, Bortolotti CA, Di Rocco G, Ranieri A, Sola M, Battistuzzi G. Met80 and Tyr67 affect the chemical unfolding of yeast cytochrome c: comparing the solution vs.immobilized state. RSC Chem Biol 2020. [DOI: 10.1039/d0cb00115e] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The motional regime affects the unfolding propensity and axial heme coordination of the Met80Ala and Met80Ala/Tyr67Ala variants of yeast iso-1 cytochromec.
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Affiliation(s)
| | - Lidia Lancellotti
- Department of Chemistry and Geology
- University of Modena and Reggio Emilia
- 41126 Modena
- Italy
| | - Marco Borsari
- Department of Chemistry and Geology
- University of Modena and Reggio Emilia
- 41126 Modena
- Italy
| | - Marzia Bellei
- Department of Life Sciences
- University of Modena and Reggio Emilia
- 41126 Modena
- Italy
| | | | - Giulia Di Rocco
- Department of Life Sciences
- University of Modena and Reggio Emilia
- 41126 Modena
- Italy
| | - Antonio Ranieri
- Department of Life Sciences
- University of Modena and Reggio Emilia
- 41126 Modena
- Italy
| | - Marco Sola
- Department of Life Sciences
- University of Modena and Reggio Emilia
- 41126 Modena
- Italy
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11
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Barreto GA, Carepo MSP, Gondim ACS, Guimarães WG, Lopes LGF, Bernhardt PV, Paulo TF, Sousa EHS, Diógenes ICN. A spectroelectrochemical investigation of the heme-based sensor DevS from Mycobacterium tuberculosis: a redox versus oxygen sensor. FEBS J 2019; 286:4278-4293. [PMID: 31254441 DOI: 10.1111/febs.14974] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Revised: 05/10/2019] [Accepted: 06/27/2019] [Indexed: 01/09/2023]
Abstract
Tuberculosis is one of the oldest known infectious diseases, responsible for millions of deaths annually around the world. The ability of Mycobacterium tuberculosis (Mtb) to enter into a dormant state has been considered integral to the success of this bacterium as a human pathogen. One of the key systems involved in regulating the entrance into dormancy is the differentially expressed in virulent strain sensor protein (DevS) [(dormancy survival sensor protein (DosS)]. However, the physiological signal for DevS has remained unclear since it was first shown to be a heme-based sensor with conflicting reports on whether it is a redox or an oxygen sensor. To address this question and provide a better understanding of the electronic properties of this protein, we present here, for the first time, a series of spectroelectrochemistry measurements of the full-length holo DevS in anaerobic conditions as well as bound to CO, NO, imidazole (Imz), cyanide, and O2 . An interesting feature of this protein is its ability to bind Imz even in the ferrous state, implying small-molecule analogues could be designed as potential regulators. Nonetheless, a midpoint potential (Em ) value of +10 mV [vs normal hydrogen electrode (NHE)] for DevS as measured under anaerobic conditions is much higher than the expected cytosolic potential for Mtb or even within stimulated macrophages (~ -270 mV vs NHE), indicating this sensor works in a reduced ferrous state. These data, along with the high oxygen affinity and very slow auto-oxidation rate of DevS, provides evidence that it is not a redox sensor. Overall, this study validates the biological function of DevS as an oxygen sensor directly involved in the dormancy/latency of Mtb.
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Affiliation(s)
- Giamwemberg A Barreto
- Laboratório de Bioinorgânica, Departamento de Química Orgânica e Inorgânica, Universidade Federal do Ceará, Fortaleza, Ceará, Brazil
| | - Marta S P Carepo
- Laboratório de Bioinorgânica, Departamento de Química Orgânica e Inorgânica, Universidade Federal do Ceará, Fortaleza, Ceará, Brazil.,UCIBIO, REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Caparica, Portugal
| | - Ana C S Gondim
- Laboratório de Bioinorgânica, Departamento de Química Orgânica e Inorgânica, Universidade Federal do Ceará, Fortaleza, Ceará, Brazil
| | - Wellinson G Guimarães
- Laboratório de Bioinorgânica, Departamento de Química Orgânica e Inorgânica, Universidade Federal do Ceará, Fortaleza, Ceará, Brazil
| | - Luiz G F Lopes
- Laboratório de Bioinorgânica, Departamento de Química Orgânica e Inorgânica, Universidade Federal do Ceará, Fortaleza, Ceará, Brazil
| | - Paul V Bernhardt
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Queensland, Australia
| | - Tércio F Paulo
- Laboratório de Bioinorgânica, Departamento de Química Orgânica e Inorgânica, Universidade Federal do Ceará, Fortaleza, Ceará, Brazil
| | - Eduardo H S Sousa
- Laboratório de Bioinorgânica, Departamento de Química Orgânica e Inorgânica, Universidade Federal do Ceará, Fortaleza, Ceará, Brazil
| | - Izaura C N Diógenes
- Laboratório de Bioinorgânica, Departamento de Química Orgânica e Inorgânica, Universidade Federal do Ceará, Fortaleza, Ceará, Brazil
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12
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Redox thermodynamics of B-class dye-decolorizing peroxidases. J Inorg Biochem 2019; 199:110761. [PMID: 31325671 DOI: 10.1016/j.jinorgbio.2019.110761] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Revised: 06/22/2019] [Accepted: 07/08/2019] [Indexed: 11/23/2022]
Abstract
With >5000 annotated genes dye-decolorizing peroxidases (DyPs) represent a heme b peroxidase family of broad functional diversity. Bacterial B-class DyPs are poor peroxidases of unknown physiological function. Hydrogen peroxide efficiently mediates the rapid formation of Compound I in B-class DyPs, which, however, is stable and shows modest reactivity towards organic and inorganic electron donors. To understand these characteristics, we have investigated the redox thermodynamics of the one-electron reduction of the ferric high-spin form of wild-type B-class DyP from the pathogenic bacterium Klebsiella pneumoniae (KpDyP) and the variants D143A, R232A and D143A/R232A. These distal amino acids are fully conserved in all DyPs and play important roles in Compound I formation and maintenance of the heme cavity architecture and substrate access route(s). The E°' values of the respective redox couples Fe(III)/Fe(II) varied from -350 mV (wild-type KpDyP) to -299 mV (D143A/R232A) at pH 7.0. Variable-temperature spectroelectrochemical experiments revealed that the reduction reaction of B-class DyPs is enthalpically unfavored but entropically favored with significant differences in enthalpic and entropic contributions to E°' between the four proteins. Molecular dynamics simulations demonstrated the impact of solvent reorganization on the entropy change during reduction reaction and revealed the dynamics and restriction of substrate access channels. Obtained data are discussed with respect to the poor peroxidase activities of B-class DyPs and compared with heme peroxidases from other (super)families as well as with chlorite dismutases, which do not react with hydrogen peroxide but share a similar fold and heme cavity architecture.
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13
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Fontana LA, Siqueira JD, Ceolin J, Iglesias BA, Piquini PC, Neves A, Back DF. Peroxidase activity of new mixed‐valence cobalt complexes with ligands derived from pyridoxal. Appl Organomet Chem 2019. [DOI: 10.1002/aoc.4903] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- Liniquer André Fontana
- Laboratório de Materiais Inorgânicos – Departamento de QuímicaCCNE, UFSM 97105‐900 Santa Maria RS Brazil
| | - Josiéli Demetrio Siqueira
- Laboratório de Materiais Inorgânicos – Departamento de QuímicaCCNE, UFSM 97105‐900 Santa Maria RS Brazil
| | - Joice Ceolin
- Laboratório de Materiais Inorgânicos – Departamento de QuímicaCCNE, UFSM 97105‐900 Santa Maria RS Brazil
| | | | | | - Ademir Neves
- Departamento de QuímicaUniversidade Federal de Santa Catarina, UFSC 88040‐970 Florianópolis SC Brazil
| | - Davi Fernando Back
- Laboratório de Materiais Inorgânicos – Departamento de QuímicaCCNE, UFSM 97105‐900 Santa Maria RS Brazil
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14
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Nicolussi A, Auer M, Sevcnikar B, Paumann-Page M, Pfanzagl V, Zámocký M, Hofbauer S, Furtmüller PG, Obinger C. Posttranslational modification of heme in peroxidases – Impact on structure and catalysis. Arch Biochem Biophys 2018; 643:14-23. [DOI: 10.1016/j.abb.2018.02.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2018] [Revised: 02/12/2018] [Accepted: 02/13/2018] [Indexed: 12/16/2022]
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15
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Bellei M, Bortolotti CA, Di Rocco G, Borsari M, Lancellotti L, Ranieri A, Sola M, Battistuzzi G. The influence of the Cys46/Cys55 disulfide bond on the redox and spectroscopic properties of human neuroglobin. J Inorg Biochem 2018; 178:70-86. [DOI: 10.1016/j.jinorgbio.2017.10.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Revised: 09/21/2017] [Accepted: 10/09/2017] [Indexed: 12/21/2022]
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16
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Paumann-Page M, Katz RS, Bellei M, Schwartz I, Edenhofer E, Sevcnikar B, Soudi M, Hofbauer S, Battistuzzi G, Furtmüller PG, Obinger C. Pre-steady-state Kinetics Reveal the Substrate Specificity and Mechanism of Halide Oxidation of Truncated Human Peroxidasin 1. J Biol Chem 2017; 292:4583-4592. [PMID: 28154175 PMCID: PMC5377774 DOI: 10.1074/jbc.m117.775213] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Revised: 01/24/2017] [Indexed: 11/23/2022] Open
Abstract
Human peroxidasin 1 is a homotrimeric multidomain peroxidase that is secreted to the extracellular matrix. The heme enzyme was shown to release hypobromous acid that mediates the formation of specific covalent sulfilimine bonds to reinforce collagen IV in basement membranes. Maturation by proteolytic cleavage is known to activate the enzyme. Here, we present the first multimixing stopped-flow study on a fully functional truncated variant of human peroxidasin 1 comprising four immunoglobulin-like domains and the catalytically active peroxidase domain. The kinetic data unravel the so far unknown substrate specificity and mechanism of halide oxidation of human peroxidasin 1. The heme enzyme is shown to follow the halogenation cycle that is induced by the rapid H2O2-mediated oxidation of the ferric enzyme to the redox intermediate compound I. We demonstrate that chloride cannot act as a two-electron donor of compound I, whereas thiocyanate, iodide, and bromide efficiently restore the ferric resting state. We present all relevant apparent bimolecular rate constants, the spectral signatures of the redox intermediates, and the standard reduction potential of the Fe(III)/Fe(II) couple, and we demonstrate that the prosthetic heme group is post-translationally modified and cross-linked with the protein. These structural features provide the basis of human peroxidasin 1 to act as an effective generator of hypobromous acid, which mediates the formation of covalent cross-links in collagen IV.
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Affiliation(s)
- Martina Paumann-Page
- From the Department of Chemistry, Division of Biochemistry, Vienna Institute of BioTechnology, BOKU-University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria and
| | - Romy-Sophie Katz
- From the Department of Chemistry, Division of Biochemistry, Vienna Institute of BioTechnology, BOKU-University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria and
| | | | - Irene Schwartz
- From the Department of Chemistry, Division of Biochemistry, Vienna Institute of BioTechnology, BOKU-University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria and
| | - Eva Edenhofer
- From the Department of Chemistry, Division of Biochemistry, Vienna Institute of BioTechnology, BOKU-University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria and
| | - Benjamin Sevcnikar
- From the Department of Chemistry, Division of Biochemistry, Vienna Institute of BioTechnology, BOKU-University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria and
| | - Monika Soudi
- From the Department of Chemistry, Division of Biochemistry, Vienna Institute of BioTechnology, BOKU-University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria and
| | - Stefan Hofbauer
- From the Department of Chemistry, Division of Biochemistry, Vienna Institute of BioTechnology, BOKU-University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria and
| | | | - Paul G Furtmüller
- From the Department of Chemistry, Division of Biochemistry, Vienna Institute of BioTechnology, BOKU-University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria and
| | - Christian Obinger
- From the Department of Chemistry, Division of Biochemistry, Vienna Institute of BioTechnology, BOKU-University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria and
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17
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Ryu WH, Gittleson FS, Thomsen JM, Li J, Schwab MJ, Brudvig GW, Taylor AD. Heme biomolecule as redox mediator and oxygen shuttle for efficient charging of lithium-oxygen batteries. Nat Commun 2016; 7:12925. [PMID: 27759005 PMCID: PMC5075788 DOI: 10.1038/ncomms12925] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2016] [Accepted: 08/16/2016] [Indexed: 12/23/2022] Open
Abstract
One of the greatest challenges with lithium-oxygen batteries involves identifying catalysts that facilitate the growth and evolution of cathode species on an oxygen electrode. Heterogeneous solid catalysts cannot adequately address the problematic overpotentials when the surfaces become passivated. However, there exists a class of biomolecules which have been designed by nature to guide complex solution-based oxygen chemistries. Here, we show that the heme molecule, a common porphyrin cofactor in blood, can function as a soluble redox catalyst and oxygen shuttle for efficient oxygen evolution in non-aqueous Li-O2 batteries. The heme's oxygen binding capability facilitates battery recharge by accepting and releasing dissociated oxygen species while benefiting charge transfer with the cathode. We reveal the chemical change of heme redox molecules where synergy exists with the electrolyte species. This study brings focus to the rational design of solution-based catalysts and suggests a sustainable cross-link between biomolecules and advanced energy storage.
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Affiliation(s)
- Won-Hee Ryu
- Department of Chemical and Environmental Engineering, Yale University, 9 Hillhouse Avenue, New Haven, Connecticut, USA
- Department of Chemical and Biological Engineering, Sookmyung Women's University, 100 Cheongpa-ro 47-gil, Yongsan-gu, Seoul, Republic of Korea
- The Nature Conservancy, Arlington, Virginia, USA
| | - Forrest S. Gittleson
- Department of Chemical and Environmental Engineering, Yale University, 9 Hillhouse Avenue, New Haven, Connecticut, USA
- Materials Chemistry Department, Sandia National Laboratories, 7011 East Avenue, Livermore, California 94550, USA
| | - Julianne M. Thomsen
- Department of Chemistry, Yale University, 225 Prospect Street, New Haven, Connecticut, USA
| | - Jinyang Li
- Department of Chemical and Environmental Engineering, Yale University, 9 Hillhouse Avenue, New Haven, Connecticut, USA
| | - Mark J. Schwab
- Department of Chemical and Environmental Engineering, Yale University, 9 Hillhouse Avenue, New Haven, Connecticut, USA
| | - Gary W. Brudvig
- Department of Chemistry, Yale University, 225 Prospect Street, New Haven, Connecticut, USA
| | - André D. Taylor
- Department of Chemical and Environmental Engineering, Yale University, 9 Hillhouse Avenue, New Haven, Connecticut, USA
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18
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Hofbauer S, Dalla Sega M, Scheiblbrandner S, Jandova Z, Schaffner I, Mlynek G, Djinović-Carugo K, Battistuzzi G, Furtmüller PG, Oostenbrink C, Obinger C. Chemistry and Molecular Dynamics Simulations of Heme b-HemQ and Coproheme-HemQ. Biochemistry 2016; 55:5398-412. [PMID: 27599156 PMCID: PMC5041162 DOI: 10.1021/acs.biochem.6b00701] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Recently, a novel pathway for heme b biosynthesis in Gram-positive bacteria has been proposed. The final poorly understood step is catalyzed by an enzyme called HemQ and includes two decarboxylation reactions leading from coproheme to heme b. Coproheme has been suggested to act as both substrate and redox active cofactor in this reaction. In the study presented here, we focus on HemQs from Listeria monocytogenes (LmHemQ) and Staphylococcus aureus (SaHemQ) recombinantly produced as apoproteins in Escherichia coli. We demonstrate the rapid and two-phase uptake of coproheme by both apo forms and the significant differences in thermal stability of the apo forms, coproheme-HemQ and heme b-HemQ. Reduction of ferric high-spin coproheme-HemQ to the ferrous form is shown to be enthalpically favored but entropically disfavored with standard reduction potentials of -205 ± 3 mV for LmHemQ and -207 ± 3 mV for SaHemQ versus the standard hydrogen electrode at pH 7.0. Redox thermodynamics suggests the presence of a pronounced H-bonding network and restricted solvent mobility in the heme cavity. Binding of cyanide to the sixth coproheme position is monophasic but relatively slow (∼1 × 10(4) M(-1) s(-1)). On the basis of the available structures of apo-HemQ and modeling of both loaded forms, molecular dynamics simulation allowed analysis of the interaction of coproheme and heme b with the protein as well as the role of the flexibility at the proximal heme cavity and the substrate access channel for coproheme binding and heme b release. Obtained data are discussed with respect to the proposed function of HemQ in monoderm bacteria.
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Affiliation(s)
- Stefan Hofbauer
- Department for Structural and Computational Biology, Max F. Perutz Laboratories, University of Vienna , A-1030 Vienna, Austria
| | - Marco Dalla Sega
- Department of Material Sciences and Process Engineering, Institute of Molecular Modeling and Simulation, BOKU-University of Natural Resources and Life Sciences , A-1190 Vienna, Austria
| | - Stefan Scheiblbrandner
- Department of Food Science and Technology, Food Biotechnology Laboratory, BOKU-University of Natural Resources and Life Sciences , A-1190 Vienna, Austria
| | - Zuzana Jandova
- Department of Material Sciences and Process Engineering, Institute of Molecular Modeling and Simulation, BOKU-University of Natural Resources and Life Sciences , A-1190 Vienna, Austria
| | - Irene Schaffner
- Department of Chemistry, Division of Biochemistry, VIBT-Vienna Institute of BioTechnology, BOKU-University of Natural Resources and Life Sciences , A-1190 Vienna, Austria
| | - Georg Mlynek
- Department for Structural and Computational Biology, Max F. Perutz Laboratories, University of Vienna , A-1030 Vienna, Austria
| | - Kristina Djinović-Carugo
- Department for Structural and Computational Biology, Max F. Perutz Laboratories, University of Vienna , A-1030 Vienna, Austria.,Department of Biochemistry, Faculty of Chemistry and Chemical Technology, University of Ljubljana , 1000 Ljubljana, Slovenia
| | - Gianantonio Battistuzzi
- Department of Chemistry and Geology, University of Modena and Reggio Emilia , 41125 Modena, Italy
| | - Paul G Furtmüller
- Department of Chemistry, Division of Biochemistry, VIBT-Vienna Institute of BioTechnology, BOKU-University of Natural Resources and Life Sciences , A-1190 Vienna, Austria
| | - Chris Oostenbrink
- Department of Material Sciences and Process Engineering, Institute of Molecular Modeling and Simulation, BOKU-University of Natural Resources and Life Sciences , A-1190 Vienna, Austria
| | - Christian Obinger
- Department of Chemistry, Division of Biochemistry, VIBT-Vienna Institute of BioTechnology, BOKU-University of Natural Resources and Life Sciences , A-1190 Vienna, Austria
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19
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Soudi M, Paumann-Page M, Delporte C, Pirker KF, Bellei M, Edenhofer E, Stadlmayr G, Battistuzzi G, Boudjeltia KZ, Furtmüller PG, Van Antwerpen P, Obinger C. Multidomain human peroxidasin 1 is a highly glycosylated and stable homotrimeric high spin ferric peroxidase. J Biol Chem 2015; 290:10876-90. [PMID: 25713063 PMCID: PMC4409251 DOI: 10.1074/jbc.m114.632273] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Revised: 02/18/2015] [Indexed: 12/31/2022] Open
Abstract
Human peroxidasin 1 (hsPxd01) is a multidomain heme peroxidase that uses bromide as a cofactor for the formation of sulfilimine cross-links. The latter confers critical structural reinforcement to collagen IV scaffolds. Here, hsPxd01 and various truncated variants lacking nonenzymatic domains were recombinantly expressed in HEK cell lines. The N-glycosylation site occupancy and disulfide pattern, the oligomeric structure, and unfolding pathway are reported. The homotrimeric iron protein contains a covalently bound ferric high spin heme per subunit with a standard reduction potential of the Fe(III)/Fe(II) couple of -233 ± 5 mV at pH 7.0. Despite sequence homology at the active site and biophysical properties similar to human peroxidases, the catalytic efficiency of bromide oxidation (kcat/KM(app)) of full-length hsPxd01 is rather low but increased upon truncation. This is discussed with respect to its structure and proposed biosynthetic function in collagen IV cross-linking.
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Affiliation(s)
- Monika Soudi
- From the Department of Chemistry, Division of Biochemistry, BOKU-University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
| | - Martina Paumann-Page
- From the Department of Chemistry, Division of Biochemistry, BOKU-University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
| | - Cedric Delporte
- the Laboratory of Pharmaceutical Chemistry and Analytical Platform of the Faculty of Pharmacy, Faculty of Pharmacy, Université Libre de Bruxelles, 1050 Brussels, Belgium
| | - Katharina F Pirker
- From the Department of Chemistry, Division of Biochemistry, BOKU-University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
| | | | - Eva Edenhofer
- From the Department of Chemistry, Division of Biochemistry, BOKU-University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
| | - Gerhard Stadlmayr
- From the Department of Chemistry, Division of Biochemistry, BOKU-University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
| | | | - Karim Zouaoui Boudjeltia
- the Laboratory of Experimental Medicine (ULB 222 Unit), CHU de Charleroi, A. Vésale Hospital, Université Libre de Bruxelles, 6110 Montigny-le-Tilleul, Belgium
| | - Paul G Furtmüller
- From the Department of Chemistry, Division of Biochemistry, BOKU-University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
| | - Pierre Van Antwerpen
- the Laboratory of Pharmaceutical Chemistry and Analytical Platform of the Faculty of Pharmacy, Faculty of Pharmacy, Université Libre de Bruxelles, 1050 Brussels, Belgium
| | - Christian Obinger
- From the Department of Chemistry, Division of Biochemistry, BOKU-University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria,
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20
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Schaffner I, Hofbauer S, Krutzler M, Pirker KF, Bellei M, Stadlmayr G, Mlynek G, Djinovic-Carugo K, Battistuzzi G, Furtmüller PG, Daims H, Obinger C. Dimeric chlorite dismutase from the nitrogen-fixing cyanobacterium Cyanothece sp. PCC7425. Mol Microbiol 2015; 96:1053-68. [PMID: 25732258 PMCID: PMC4973843 DOI: 10.1111/mmi.12989] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/01/2015] [Indexed: 11/28/2022]
Abstract
It is demonstrated that cyanobacteria (both azotrophic and non-azotrophic) contain heme b oxidoreductases that can convert chlorite to chloride and molecular oxygen (incorrectly denominated chlorite 'dismutase', Cld). Beside the water-splitting manganese complex of photosystem II, this metalloenzyme is the second known enzyme that catalyses the formation of a covalent oxygen-oxygen bond. All cyanobacterial Clds have a truncated N-terminus and are dimeric (i.e. clade 2) proteins. As model protein, Cld from Cyanothece sp. PCC7425 (CCld) was recombinantly produced in Escherichia coli and shown to efficiently degrade chlorite with an activity optimum at pH 5.0 [kcat 1144 ± 23.8 s(-1), KM 162 ± 10.0 μM, catalytic efficiency (7.1 ± 0.6) × 10(6) M(-1) s(-1)]. The resting ferric high-spin axially symmetric heme enzyme has a standard reduction potential of the Fe(III)/Fe(II) couple of -126 ± 1.9 mV at pH 7.0. Cyanide mediates the formation of a low-spin complex with k(on) = (1.6 ± 0.1) × 10(5) M(-1) s(-1) and k(off) = 1.4 ± 2.9 s(-1) (KD ∼ 8.6 μM). Both, thermal and chemical unfolding follows a non-two-state unfolding pathway with the first transition being related to the release of the prosthetic group. The obtained data are discussed with respect to known structure-function relationships of Clds. We ask for the physiological substrate and putative function of these O2 -producing proteins in (nitrogen-fixing) cyanobacteria.
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Affiliation(s)
- Irene Schaffner
- Department of Chemistry, Division of Biochemistry, BOKU - University of Natural Resources and Life Sciences, Muthgasse 18, A-1190, Vienna, Austria
| | - Stefan Hofbauer
- Department of Chemistry, Division of Biochemistry, BOKU - University of Natural Resources and Life Sciences, Muthgasse 18, A-1190, Vienna, Austria.,Department for Structural and Computational Biology, Max F. Perutz Laboratories, University of Vienna, Vienna, Austria
| | - Michael Krutzler
- Department of Chemistry, Division of Biochemistry, BOKU - University of Natural Resources and Life Sciences, Muthgasse 18, A-1190, Vienna, Austria
| | - Katharina F Pirker
- Department of Chemistry, Division of Biochemistry, BOKU - University of Natural Resources and Life Sciences, Muthgasse 18, A-1190, Vienna, Austria
| | - Marzia Bellei
- Department of Life Sciences, University of Modena and Reggio Emilia, 41125, Modena, Italy
| | - Gerhard Stadlmayr
- Department of Chemistry, Division of Biochemistry, BOKU - University of Natural Resources and Life Sciences, Muthgasse 18, A-1190, Vienna, Austria
| | - Georg Mlynek
- Department for Structural and Computational Biology, Max F. Perutz Laboratories, University of Vienna, Vienna, Austria
| | - Kristina Djinovic-Carugo
- Department for Structural and Computational Biology, Max F. Perutz Laboratories, University of Vienna, Vienna, Austria.,Department of Biochemistry, Faculty of Chemistry and Chemical Technology, University of Ljubljana, 1000, Ljubljana, Slovenia
| | - Gianantonio Battistuzzi
- Department of Chemistry and Geology, University of Modena and Reggio Emilia, 41125, Modena, Italy
| | - Paul G Furtmüller
- Department of Chemistry, Division of Biochemistry, BOKU - University of Natural Resources and Life Sciences, Muthgasse 18, A-1190, Vienna, Austria
| | - Holger Daims
- Department of Microbiology and Ecosystem Science, Division of Microbial Ecology, University of Vienna, Vienna, Austria
| | - Christian Obinger
- Department of Chemistry, Division of Biochemistry, BOKU - University of Natural Resources and Life Sciences, Muthgasse 18, A-1190, Vienna, Austria
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21
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Wu H, Liu Y, Li M, Chong Y, Zeng M, Lo YM, Yin JJ. Size-dependent tuning of horseradish peroxidase bioreactivity by gold nanoparticles. NANOSCALE 2015; 7:4505-13. [PMID: 25684572 DOI: 10.1039/c4nr07056a] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Molecules with diverse biological functions, such as heme peroxidases, can be useful tools for identifying potential biological effects of gold nanoparticles (AuNPs) at the molecular level. Here, using UV-Vis, circular dichroism, dynamic light scattering, and electron spin resonance spectroscopy, we report tuning of horseradish peroxidase (HRP) bioactivity by reactant-free AuNPs with diameters of 5, 10, 15, 30 and 60 nm (Au-5 nm, Au-10 nm, Au-15 nm, Au-30 nm and Au-60 nm). HRP conjugation to AuNPs was observed with only Au-5 nm and Au-10 nm prominently increasing the α-helicity of the enzyme to extents inversely related to their size. Au-5 nm inhibited both HRP peroxidase activity toward 3,3',5,5'-tetramethylbenzidine and HRP compound I/II reactivity toward 5,5-dimethyl-1-pyrroline N-oxide. Au-5 nm enhanced the HRP peroxidase activity toward ascorbic acid and the HRP compound I/II reactivity toward redox-active residues in the HRP protein moiety. Further, Au-5 nm also decreased the catalase- and oxidase-like activities of HRP. Au-10 nm showed similar, but weaker effects, while Au-15 nm, Au-30 nm and Au-60 nm had no effect. Results suggest that AuNPs can size-dependently enhance or inhibit HRP bioreactivity toward substrates with different redox potentials via a mechanism involving extension of the HRP substrate access channel and decline in the redox potentials of HRP catalytic intermediates.
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Affiliation(s)
- Haohao Wu
- College of Food Science and Engineering, Ocean University of China, 5 Yushan Road, Qingdao, Shandong Province 266003, China
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22
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Hofbauer S, Gysel K, Bellei M, Hagmüller A, Schaffner I, Mlynek G, Kostan J, Pirker KF, Daims H, Furtmüller PG, Battistuzzi G, Djinović-Carugo K, Obinger C. Manipulating conserved heme cavity residues of chlorite dismutase: effect on structure, redox chemistry, and reactivity. Biochemistry 2014; 53:77-89. [PMID: 24364531 PMCID: PMC3893830 DOI: 10.1021/bi401042z] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
Chlorite dismutases (Clds) are heme b containing
oxidoreductases that convert chlorite to chloride and molecular oxygen.
In order to elucidate the role of conserved heme cavity residues in
the catalysis of this reaction comprehensive mutational and biochemical
analyses of Cld from “Candidatus Nitrospira
defluvii” (NdCld) were performed. Particularly, point mutations
of the cavity-forming residues R173, K141, W145, W146, and E210 were
performed. The effect of manipulation in 12 single and double mutants
was probed by UV–vis spectroscopy, spectroelectrochemistry,
pre-steady-state and steady-state kinetics, and X-ray crystallography.
Resulting biochemical data are discussed with respect to the known
crystal structure of wild-type NdCld and the variants R173A and R173K
as well as the structures of R173E, W145V, W145F, and the R173Q/W146Y
solved in this work. The findings allow a critical analysis of the
role of these heme cavity residues in the reaction mechanism of chlorite
degradation that is proposed to involve hypohalous acid as transient
intermediate and formation of an O=O bond. The distal R173
is shown to be important (but not fully essential) for the reaction
with chlorite, and, upon addition of cyanide, it acts as a proton
acceptor in the formation of the resulting low-spin complex. The proximal
H-bonding network including K141-E210-H160 keeps the enzyme in its
ferric (E°′ = −113 mV) and mainly
five-coordinated high-spin state and is very susceptible to perturbation.
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Affiliation(s)
- Stefan Hofbauer
- Department of Chemistry, Division of Biochemistry, VIBT - Vienna Institute of BioTechnology, BOKU - University of Natural Resources and Life Sciences , A-1190 Vienna, Austria
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23
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Auer M, Gruber C, Bellei M, Pirker KF, Zamocky M, Kroiss D, Teufer SA, Hofbauer S, Soudi M, Battistuzzi G, Furtmüller PG, Obinger C. A stable bacterial peroxidase with novel halogenating activity and an autocatalytically linked heme prosthetic group. J Biol Chem 2013; 288:27181-27199. [PMID: 23918925 DOI: 10.1074/jbc.m113.477067] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Reconstructing the phylogenetic relationships of the main evolutionary lines of the mammalian peroxidases lactoperoxidase and myeloperoxidase revealed the presence of novel bacterial heme peroxidase subfamilies. Here, for the first time, an ancestral bacterial heme peroxidase is shown to possess a very high bromide oxidation activity (besides conventional peroxidase activity). The recombinant protein allowed monitoring of the autocatalytic peroxide-driven formation of covalent heme to protein bonds. Thereby, the high spin ferric rhombic heme spectrum became similar to lactoperoxidase, the standard reduction potential of the Fe(III)/Fe(II) couple shifted to more positive values (-145 ± 10 mV at pH 7), and the conformational and thermal stability of the protein increased significantly. We discuss structure-function relationships of this new peroxidase in relation to its mammalian counterparts and ask for its putative physiological role.
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Affiliation(s)
- Markus Auer
- Division of Biochemistry, Department of Chemistry, Vienna Institute of BioTechnology, BOKU-University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
| | - Clemens Gruber
- Division of Biochemistry, Department of Chemistry, Vienna Institute of BioTechnology, BOKU-University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
| | | | - Katharina F Pirker
- Division of Biochemistry, Department of Chemistry, Vienna Institute of BioTechnology, BOKU-University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
| | - Marcel Zamocky
- Division of Biochemistry, Department of Chemistry, Vienna Institute of BioTechnology, BOKU-University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria; Institute of Molecular Biology, Slovak Academy of Sciences, 84551 Bratislava, Slovakia
| | - Daniela Kroiss
- Division of Biochemistry, Department of Chemistry, Vienna Institute of BioTechnology, BOKU-University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
| | - Stefan A Teufer
- Division of Biochemistry, Department of Chemistry, Vienna Institute of BioTechnology, BOKU-University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
| | - Stefan Hofbauer
- Division of Biochemistry, Department of Chemistry, Vienna Institute of BioTechnology, BOKU-University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
| | - Monika Soudi
- Division of Biochemistry, Department of Chemistry, Vienna Institute of BioTechnology, BOKU-University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
| | - Gianantonio Battistuzzi
- Departments of Chemistry and Geology, University of Modena and Reggio Emilia, 41100 Modena, Italy
| | - Paul G Furtmüller
- Division of Biochemistry, Department of Chemistry, Vienna Institute of BioTechnology, BOKU-University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
| | - Christian Obinger
- Division of Biochemistry, Department of Chemistry, Vienna Institute of BioTechnology, BOKU-University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria.
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24
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Sezer M, Santos A, Kielb P, Pinto T, Martins LO, Todorovic S. Distinct structural and redox properties of the heme active site in bacterial dye decolorizing peroxidase-type peroxidases from two subfamilies: resonance Raman and electrochemical study. Biochemistry 2013; 52:3074-84. [PMID: 23560556 DOI: 10.1021/bi301630a] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Spectroscopic data of dye decolorizing peroxidases (DyPs) from Bacillus subtilis (BsDyP), an A subfamily member, and Pseudomonas putida (PpDyP), a B subfamily enzyme, reveal distinct heme coordination patterns of the respective active sites. In solution, both enzymes show a heterogeneous spin population, with the six-coordinated low-spin state being the most populated in the former and the five-coordinated quantum mechanically mixed-spin state in the latter. We ascribe the poor catalytic activity of BsDyP to the presence of a catalytically incompetent six-coordinated low-spin population. The spin populations of the two DyPs are sensitively dependent on the pH, temperature, and physical, i.e., solution versus crystal versus immobilized, state of the enzymes. We observe a redox potential for the Fe(2+)/Fe(3+) couple in BsDyP (-40 mV) at pH 7.6 substantially more positive than those reported for the majority of other peroxidases, including PpDyP (-260 mV). Furthermore, we evaluate the potential of the studied enzymes for biotechnological applications on the basis of electrochemical and spectroelectrochemical data.
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Affiliation(s)
- Murat Sezer
- Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Av. da Republica, 2780-157 Oeiras, Portugal
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25
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Hofbauer S, Bellei M, Sündermann A, Pirker KF, Hagmüller A, Mlynek G, Kostan J, Daims H, Furtmüller PG, Djinović-Carugo K, Oostenbrink C, Battistuzzi G, Obinger C. Redox thermodynamics of high-spin and low-spin forms of chlorite dismutases with diverse subunit and oligomeric structures. Biochemistry 2012; 51:9501-12. [PMID: 23126649 PMCID: PMC3557923 DOI: 10.1021/bi3013033] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
Chlorite dismutases (Clds) are heme b-containing
oxidoreductases that convert chlorite to chloride and dioxygen. In
this work, the thermodynamics of the one-electron reduction of the
ferric high-spin forms and of the six-coordinate low-spin cyanide
adducts of the enzymes from Nitrobacter winogradskyi (NwCld) and Candidatus “Nitrospira defluvii”
(NdCld) were determined through spectroelectrochemical experiments.
These proteins belong to two phylogenetically separated lineages that
differ in subunit (21.5 and 26 kDa, respectively) and oligomeric (dimeric
and pentameric, respectively) structure but exhibit similar chlorite
degradation activity. The E°′ values
for free and cyanide-bound proteins were determined to be −119
and −397 mV for NwCld and −113 and −404 mV for
NdCld, respectively (pH 7.0, 25 °C). Variable-temperature spectroelectrochemical
experiments revealed that the oxidized state of both proteins is enthalpically
stabilized. Molecular dynamics simulations suggest that changes in
the protein structure are negligible, whereas solvent reorganization
is mainly responsible for the increase in entropy during the redox
reaction. Obtained data are discussed with respect to the known structures
of the two Clds and the proposed reaction mechanism.
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Affiliation(s)
- Stefan Hofbauer
- Department of Chemistry, Division of Biochemistry, VIBT-Vienna Institute of BioTechnology, BOKU-University of Natural Resources and Life Sciences, A-1190 Vienna, Austria
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26
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Manipulating the proximal triad His–Asn–Arg in human myeloperoxidase. Arch Biochem Biophys 2011; 516:21-8. [DOI: 10.1016/j.abb.2011.09.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2011] [Revised: 09/01/2011] [Accepted: 09/13/2011] [Indexed: 12/31/2022]
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Battistuzzi G, Stampler J, Bellei M, Vlasits J, Soudi M, Furtmüller PG, Obinger C. Influence of the Covalent Heme–Protein Bonds on the Redox Thermodynamics of Human Myeloperoxidase. Biochemistry 2011; 50:7987-94. [DOI: 10.1021/bi2008432] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- Gianantonio Battistuzzi
- Department of Chemistry, University of Modena and Reggio Emilia, via Campi 183,
41100 Modena, Italy
| | - Johanna Stampler
- Vienna
Institute of BioTechnology,
Department of Chemistry, Division of Biochemistry, BOKU-University of Natural Resources and Life Sciences, Muthgasse 18,
A-1190 Vienna, Austria
| | - Marzia Bellei
- Department of Chemistry, University of Modena and Reggio Emilia, via Campi 183,
41100 Modena, Italy
| | - Jutta Vlasits
- Vienna
Institute of BioTechnology,
Department of Chemistry, Division of Biochemistry, BOKU-University of Natural Resources and Life Sciences, Muthgasse 18,
A-1190 Vienna, Austria
| | - Monika Soudi
- Vienna
Institute of BioTechnology,
Department of Chemistry, Division of Biochemistry, BOKU-University of Natural Resources and Life Sciences, Muthgasse 18,
A-1190 Vienna, Austria
| | - Paul G. Furtmüller
- Vienna
Institute of BioTechnology,
Department of Chemistry, Division of Biochemistry, BOKU-University of Natural Resources and Life Sciences, Muthgasse 18,
A-1190 Vienna, Austria
| | - Christian Obinger
- Vienna
Institute of BioTechnology,
Department of Chemistry, Division of Biochemistry, BOKU-University of Natural Resources and Life Sciences, Muthgasse 18,
A-1190 Vienna, Austria
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28
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Tai H, Irie K, Mikami SI, Yamamoto Y. Enhancement of the thermostability of Hydrogenobacter thermophilus cytochrome c(552) through introduction of an extra methylene group into its hydrophobic protein interior. Biochemistry 2011; 50:3161-9. [PMID: 21417336 DOI: 10.1021/bi200256d] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Careful scrutiny of the protein interior of Hydrogenobacter thermophilus cytochrome c(552) (HT) on the basis of its X-ray structure [Travaglini-Allocatelli, C., Gianni, S., Dubey, V. K., Borgia, A., Di Matteo, A., Bonivento, D., Cutruzzola, F., Bren, K. L., and Brunori, M. (2005) J. Biol. Chem. 280, 25729-25734] indicated that a void space, which is large enough to accommodate a methyl group, exists in the hydrophobic protein interior near the heme. We tried to reduce the void space through the replacement of a Val by Ile or Leu (Val/Ile or Val/Leu mutation), and then the structural and functional consequences of these two mutations were characterized in order to elucidate the relationship between the nature of the packing of hydrophobic residues and the functional properties of the protein. The study demonstrated striking differences in the structural and functional consequences between the two mutations. The Val/Ile mutation was found to cause further enhancement of the thermostability of the oxidized HT, as reflected in the increase of the denaturation temperature (T(m)) value by ∼ 3 deg, whereas the thermostability of the reduced form was essentially unaffected. As a result, the redox potential (E(m)) of the Val/Ile mutant exhibited a negative shift of ∼ 50 mV relative to that of the wild-type protein in an enthalpic manner, this being consistent with our previous finding that a protein with higher stability in its oxidized form exhibits a lower E(m) value [Terui, N., Tachiiri, N., Matsuo, H., Hasegawa, J., Uchiyama, S., Kobayashi, Y., Igarashi, Y., Sambongi, Y., and Yamamoto, Y. (2003) J. Am. Chem. Soc. 125, 13650-13651]. In contrast, the Val/Leu mutation led to a decrease in thermostability of both the redox forms of the protein, as reflected in the decreases of the T(m) values of the oxidized and reduced proteins by ∼ 3 and ∼ 5 deg, respectively, and the E(m) value of the Val/Leu mutant happened to be similar to that of the Val/Ile one. The E(m) value of the Val/Leu mutant could be reasonably interpreted in terms of the different effects of the mutation on the stabilities of the two different redox forms of the protein. Thus, the present study demonstrated that the stability of the protein is affected quite sensitively by the contextual stereochemical packing of hydrophobic residues in the protein interior and that the structural properties of the hydrophobic core in the protein interior are crucial for control of the redox function of the protein. These findings provide novel insights as to functional control of a protein, which could be utilized for tuning of the T(m) and E(m) values of the protein by means of protein engineering.
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Affiliation(s)
- Hulin Tai
- Department of Chemistry, University of Tsukuba, Tsukuba 305-8571, Japan
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29
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O'Reilly NJ, Magner E. The effect of solvent on the catalytic properties of microperoxidase-11. Phys Chem Chem Phys 2011; 13:5304-13. [DOI: 10.1039/c0cp02321c] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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30
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Waldeck DH, Khoshtariya DE. Fundamental Studies of Long- and Short-Range Electron Exchange Mechanisms between Electrodes and Proteins. MODERN ASPECTS OF ELECTROCHEMISTRY 2011. [DOI: 10.1007/978-1-4614-0347-0_2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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31
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de Serrano VS, Davis MF, Gaff JF, Zhang Q, Chen Z, D'Antonio EL, Bowden EF, Rose R, Franzen S. X-ray structure of the metcyano form of dehaloperoxidase fromAmphitrite ornata: evidence for photoreductive dissociation of the iron–cyanide bond. ACTA CRYSTALLOGRAPHICA SECTION D: BIOLOGICAL CRYSTALLOGRAPHY 2010; 66:770-82. [DOI: 10.1107/s0907444910014605] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2010] [Accepted: 04/20/2010] [Indexed: 11/11/2022]
Abstract
X-ray crystal structures of the metcyano form of dehaloperoxidase-hemoglobin (DHP A) fromAmphitrite ornata(DHPCN) and the C73S mutant of DHP A (C73SCN) were determined using synchrotron radiation in order to further investigate the geometry of diatomic ligands coordinated to the heme iron. The DHPCN structure was also determined using a rotating-anode source. The structures show evidence of photoreduction of the iron accompanied by dissociation of bound cyanide ion (CN−) that depend on the intensity of the X-ray radiation and the exposure time. The electron density is consistent with diatomic molecules located in two sites in the distal pocket of DHPCN. However, the identities of the diatomic ligands at these two sites are not uniquely determined by the electron-density map. Consequently, density functional theory calculations were conducted in order to determine whether the bond lengths, angles and dissociation energies are consistent with bound CN−or O2in the iron-bound site. In addition, molecular-dynamics simulations were carried out in order to determine whether the dynamics are consistent with trapped CN−or O2in the second site of the distal pocket. Based on these calculations and comparison with a previously determined X-ray crystal structure of the C73S–O2form of DHP [de Serranoet al.(2007),Acta Cryst.D63, 1094–1101], it is concluded that CN−is gradually replaced by O2as crystalline DHP is photoreduced at 100 K. The ease of photoreduction of DHP A is consistent with the reduction potential, but suggests an alternative activation mechanism for DHP A compared with other peroxidases, which typically have reduction potentials that are 0.5 V more negative. The lability of CN−at 100 K suggests that the distal pocket of DHP A has greater flexibility than most other hemoglobins.
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32
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Disruption of the H-bond network in the main access channel of catalase–peroxidase modulates enthalpy and entropy of Fe(III) reduction. J Inorg Biochem 2010; 104:648-56. [DOI: 10.1016/j.jinorgbio.2010.02.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2010] [Revised: 02/15/2010] [Accepted: 02/23/2010] [Indexed: 01/06/2023]
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33
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Battistuzzi G, Bellei M, Bortolotti CA, Sola M. Redox properties of heme peroxidases. Arch Biochem Biophys 2010; 500:21-36. [PMID: 20211593 DOI: 10.1016/j.abb.2010.03.002] [Citation(s) in RCA: 155] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2010] [Revised: 03/01/2010] [Accepted: 03/02/2010] [Indexed: 10/19/2022]
Abstract
Peroxidases are heme enzymes found in bacteria, fungi, plants and animals, which exploit the reduction of hydrogen peroxide to catalyze a number of oxidative reactions, involving a wide variety of organic and inorganic substrates. The catalytic cycle of heme peroxidases is based on three consecutive redox steps, involving two high-valent intermediates (Compound I and Compound II), which perform the oxidation of the substrates. Therefore, the thermodynamics and the kinetics of the catalytic cycle are influenced by the reduction potentials of three redox couples, namely Compound I/Fe3+, Compound I/Compound II and Compound II/Fe3+. In particular, the oxidative power of heme peroxidases is controlled by the (high) reduction potential of the latter two couples. Moreover, the rapid H2O2-mediated two-electron oxidation of peroxidases to Compound I requires a stable ferric state in physiological conditions, which depends on the reduction potential of the Fe3+/Fe2+ couple. The understanding of the molecular determinants of the reduction potentials of the above redox couples is crucial for the comprehension of the molecular determinants of the catalytic properties of heme peroxidases. This review provides an overview of the data available on the redox properties of Fe3+/Fe2+, Compound I/Fe3+, Compound I/Compound II and Compound II/Fe3+ couples in native and mutated heme peroxidases. The influence of the electron donor properties of the axial histidine and of the polarity of the heme environment is analyzed and the correlation between the redox properties of the heme group with the catalytic activity of this important class of metallo-enzymes is discussed.
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Affiliation(s)
- Gianantonio Battistuzzi
- Department of Chemistry, University of Modena and Reggio Emilia, via Campi 183, 41100 Modena, Italy.
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34
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Tai H, Mikami SI, Irie K, Watanabe N, Shinohara N, Yamamoto Y. Role of a Highly Conserved Electrostatic Interaction on the Surface of Cytochrome c in Control of the Redox Function. Biochemistry 2009; 49:42-8. [DOI: 10.1021/bi901484b] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Hulin Tai
- Department of Chemistry, University of Tsukuba, Tsukuba 305-8571, Japan
| | - Shin-ichi Mikami
- Department of Chemistry, University of Tsukuba, Tsukuba 305-8571, Japan
| | - Kiyofumi Irie
- Department of Chemistry, University of Tsukuba, Tsukuba 305-8571, Japan
| | - Naoki Watanabe
- Department of Chemistry, University of Tsukuba, Tsukuba 305-8571, Japan
| | - Naoya Shinohara
- Department of Chemistry, University of Tsukuba, Tsukuba 305-8571, Japan
| | - Yasuhiko Yamamoto
- Department of Chemistry, University of Tsukuba, Tsukuba 305-8571, Japan
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35
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Tian Y, Ran Q, Xu J, Xian Y, Peng R, Jin L. High-Quality Covalently Grafting Hemoglobin on Gold Electrodes: Characterization, Redox Thermodynamics and Bio-electrocatalysis. Chemphyschem 2009; 10:3105-11. [DOI: 10.1002/cphc.200900588] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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36
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Battistuzzi G, Bellei M, Vlasits J, Banerjee S, Furtmüller PG, Sola M, Obinger C. Redox thermodynamics of lactoperoxidase and eosinophil peroxidase. Arch Biochem Biophys 2009; 494:72-7. [PMID: 19944669 DOI: 10.1016/j.abb.2009.11.021] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2009] [Revised: 11/10/2009] [Accepted: 11/13/2009] [Indexed: 10/20/2022]
Abstract
Eosinophil peroxidase (EPO) and lactoperoxidase (LPO) are important constituents of the innate immune system of mammals. These heme enzymes belong to the peroxidase-cyclooxygenase superfamily and catalyze the oxidation of thiocyanate, bromide and nitrite to hypothiocyanate, hypobromous acid and nitrogen dioxide that are toxic for invading pathogens. In order to gain a better understanding of the observed differences in substrate specificity and oxidation capacity in relation to heme and protein structure, a comprehensive spectro-electrochemical investigation was performed. The reduction potential (E degrees ') of the Fe(III)/Fe(II) couple of EPO and LPO was determined to be -126mV and -176mV, respectively (25 degrees C, pH 7.0). Variable temperature experiments show that EPO and LPO feature different reduction thermodynamics. In particular, reduction of ferric EPO is enthalpically and entropically disfavored, whereas in LPO the entropic term, which selectively stabilizes the oxidized form, prevails on the enthalpic term that favors reduction of Fe(III). The data are discussed with respect to the architecture of the heme cavity and the substrate channel. Comparison with published data for myeloperoxidase demonstrates the effect of heme to protein linkages and heme distortion on the redox chemistry of mammalian peroxidases and in consequence on the enzymatic properties of these physiologically important oxidoreductases.
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Affiliation(s)
- Gianantonio Battistuzzi
- Department of Chemistry, University of Modena and Reggio Emilia, via Campi 183, Modena, Italy.
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37
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Schulzke C. Temperature dependent electrochemistry--a versatile tool for investigations of biology related topics. Dalton Trans 2009:6683-91. [PMID: 19690674 DOI: 10.1039/b904361f] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Temperature dependent electrochemistry can be efficiently used to determine very different properties of the investigated system, such as thermodynamic parameters of redox processes (especially the entropy), the degeneration temperature of a protein or kinetic parameters, for instance activation energy. It can even be used in biotechnology for improved catalysis and detection of substances. This perspective describes a selection of different experiments that used temperature dependent electrochemistry in order to determine these different values or achieve an enhancement of biotechnological applications, respectively, and hence gives an overview of its versatile use in studies aimed at biological issues.
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Affiliation(s)
- Carola Schulzke
- School of Chemistry, Trinity College Dublin, Dublin 2, Ireland.
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38
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Wu F, Hu Z, Xu J, Tian Y, Wang L, Xian Y, Jin L. Immobilization of horseradish peroxidase on self-assembled (3-mercaptopropyl)trimethoxysilane film: Characterization, direct electrochemistry, redox thermodynamics and biosensing. Electrochim Acta 2008. [DOI: 10.1016/j.electacta.2008.06.031] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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39
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Ohya Y, Takamido S, Nagahama K, Ouchi T, Ooya T, Katoono R, Yui N. Molecular “Screw and Nut”: α-Cyclodextrin Recognizes Polylactide Chirality. Macromolecules 2007. [DOI: 10.1021/ma071198b] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Yuichi Ohya
- Department of Chemistry and Materials Engineering, and High Technology Research Center, Kansai University, 3-3-35 Yamate, Suita, Osaka 564-8680, Japan, and School of Materials Science, Japan Advanced Institute of Science and Technology, 1-1 Asahidai, Nomi, Ishikawa 923-1292, Japan
| | - Seigo Takamido
- Department of Chemistry and Materials Engineering, and High Technology Research Center, Kansai University, 3-3-35 Yamate, Suita, Osaka 564-8680, Japan, and School of Materials Science, Japan Advanced Institute of Science and Technology, 1-1 Asahidai, Nomi, Ishikawa 923-1292, Japan
| | - Koji Nagahama
- Department of Chemistry and Materials Engineering, and High Technology Research Center, Kansai University, 3-3-35 Yamate, Suita, Osaka 564-8680, Japan, and School of Materials Science, Japan Advanced Institute of Science and Technology, 1-1 Asahidai, Nomi, Ishikawa 923-1292, Japan
| | - Tatsuro Ouchi
- Department of Chemistry and Materials Engineering, and High Technology Research Center, Kansai University, 3-3-35 Yamate, Suita, Osaka 564-8680, Japan, and School of Materials Science, Japan Advanced Institute of Science and Technology, 1-1 Asahidai, Nomi, Ishikawa 923-1292, Japan
| | - Tooru Ooya
- Department of Chemistry and Materials Engineering, and High Technology Research Center, Kansai University, 3-3-35 Yamate, Suita, Osaka 564-8680, Japan, and School of Materials Science, Japan Advanced Institute of Science and Technology, 1-1 Asahidai, Nomi, Ishikawa 923-1292, Japan
| | - Ryo Katoono
- Department of Chemistry and Materials Engineering, and High Technology Research Center, Kansai University, 3-3-35 Yamate, Suita, Osaka 564-8680, Japan, and School of Materials Science, Japan Advanced Institute of Science and Technology, 1-1 Asahidai, Nomi, Ishikawa 923-1292, Japan
| | - Nobuhiko Yui
- Department of Chemistry and Materials Engineering, and High Technology Research Center, Kansai University, 3-3-35 Yamate, Suita, Osaka 564-8680, Japan, and School of Materials Science, Japan Advanced Institute of Science and Technology, 1-1 Asahidai, Nomi, Ishikawa 923-1292, Japan
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40
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Battistuzzi G, Bellei M, Casella L, Bortolotti CA, Roncone R, Monzani E, Sola M. Redox reactivity of the heme Fe3+/Fe2+ couple in native myoglobins and mutants with peroxidase-like activity. J Biol Inorg Chem 2007; 12:951-8. [PMID: 17576605 DOI: 10.1007/s00775-007-0267-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2007] [Accepted: 05/21/2007] [Indexed: 10/23/2022]
Abstract
The reaction enthalpy and entropy for the one-electron reduction of the ferric heme in horse heart and sperm whale aquometmyoglobins (Mb) have been determined exploiting a spectroelectrochemical approach. Also investigated were the T67R, T67K, T67R/S92D and T67R/S92D Mb-H variants (the latter containing a protoheme-L: -histidine methyl ester) of sperm whale Mb, which feature peroxidase-like activity. The reduction potential (E degrees ') in all species consists of an enthalpic term which disfavors Fe(3+) reduction and a larger entropic contribution which instead selectively stabilizes the reduced form. This behavior differs from that of the heme redox enzymes and electron transport proteins investigated so far. The reduction thermodynamics in the series of sperm whale Mb variants show an almost perfect enthalpy-entropy compensation, indicating that the mutation-induced changes in DeltaH(o')(rc) and DeltaS(o')(rc) are dominated by reduction-induced solvent reorganization effects. The modest changes in E degrees ' originate from the enthalpic effects of the electrostatic interactions of the heme with the engineered charged residues. The small influence that the mutations exert on the reduction potential of myoglobin suggests that the increased peroxidase activity of the variants is not related to changes in the redox reactivity of the heme iron, but are likely related to a more favored substrate orientation within the distal heme cavity.
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Affiliation(s)
- Gianantonio Battistuzzi
- Department of Chemistry, University of Modena and Reggio Emilia, Via Campi 183, 41100 Modena, Italy
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41
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Zederbauer M, Furtmüller PG, Brogioni S, Jakopitsch C, Smulevich G, Obinger C. Heme to protein linkages in mammalian peroxidases: impact on spectroscopic, redox and catalytic properties. Nat Prod Rep 2007; 24:571-84. [PMID: 17534531 DOI: 10.1039/b604178g] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Martina Zederbauer
- BOKU-University of Natural Resources and Applied Life Sciences, Department of Chemistry, Division of Biochemistry, Muthgasse 18, A-1190 Vienna, Austria
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42
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Battistuzzi G, Bellei M, De Rienzo F, Sola M. Redox properties of the Fe3+/Fe2+ couple in Arthromyces ramosus class II peroxidase and its cyanide adduct. J Biol Inorg Chem 2006; 11:586-92. [PMID: 16791642 DOI: 10.1007/s00775-006-0108-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2006] [Accepted: 04/10/2006] [Indexed: 10/24/2022]
Abstract
The thermodynamics of the one-electron reduction of the ferric heme in free and cyanide-bound Arthromyces ramosus peroxidase (ARP), a class II plant peroxidase, were determined through spectro-electrochemical experiments. The data were compared with those for class III horseradish peroxidase C (HRP) and its cyanide adduct, and were interpreted in terms of ligand binding features, electrostatic effects and solvent accessible surface area of the heme group and of catalytically relevant residues in the heme distal site. The E(o)' values for free and cyanide-bound ARP (-0.183 and -0.390 V, respectively, at 25 degrees C and pH 7) are higher than those for HRP and HRP-CN. ARP features an enthalpic stabilization of the ferrous state and a remarkably negative reduction entropy, which are both unprecedented for heme peroxidases. Once the compensatory contributions of solvent reorganization are partitioned from the measured reduction enthalpy, the resulting protein-based deltaH(o)'(rc(int)) value for ARP turns out to be less positive than that for HRP by +10 kJ mol(-1). The smaller stabilization of the oxidized heme in ARP most probably results from the less pronounced anionic character of the proximal histidine, and the decreased polarity in the heme distal site as compared with HRP, as indicated by the X-ray structures. The surprisingly negative deltaS(o)'(rc) value for ARP is the result of peculiar reduction-induced solvent reorganization effects.
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Affiliation(s)
- Gianantonio Battistuzzi
- Department of Chemistry and Centro SCS, University of Modena and Reggio Emilia, Via Campi 183, 41100, Modena, Italy
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43
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Battistuzzi G, Bellei M, Borsari M, Di Rocco G, Ranieri A, Sola M. Axial ligation and polypeptide matrix effects on the reduction potential of heme proteins probed on their cyanide adducts. J Biol Inorg Chem 2005; 10:643-51. [PMID: 16133205 DOI: 10.1007/s00775-005-0014-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2005] [Accepted: 07/25/2005] [Indexed: 10/25/2022]
Abstract
The enthalpic and entropic changes accompanying the reduction reaction of the six-coordinate cyanide adducts of cytochrome c, microperoxidase-11 and a few plant peroxidases were measured electrochemically. Once the compensating changes in reduction enthalpy and entropy due to solvent reorganization effects are factorized out, it is found that cyanide binding stabilizes enthalpically the ferriheme following the order: cyochrome c > peroxidase > microperoxidase-11. The effect is inversely correlated to the solvent accessibility of the heme. Comparison of the reduction thermodynamics for the cyanide adducts of cytochrome c and plant peroxidases with those for microperoxidase-11 and myoglobin, respectively, yielded an estimate of the consequences of protein encapsulation and of the anionic character of the proximal histidine on the reduction potential of the heme-cyanide group. Insertion of the heme-CN group into the folded peptide chain of cyt c induces an enthalpy-based decrease in E degrees ' of approximately 100 mV, consistent with the lower net charge of the oxidized as compared to the reduced iron center, whereas a full imidazolate character of the proximal histidine stabilizes enthalpically the ferriheme by approximately 400 mV. The latter value should be best considered as an upper limit since it also includes some solvation effects arising from the nature of the protein systems being compared.
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Affiliation(s)
- G Battistuzzi
- Department of Chemistry and Centro SCS, University of Modena and Reggio Emilia, via Campi 183, 41100, Modena, Italy
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44
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Howes BD, Brissett NC, Doyle WA, Smith AT, Smulevich G. Spectroscopic and kinetic properties of the horseradish peroxidase mutant T171S. Evidence for selective effects on the reduced state of the enzyme. FEBS J 2005; 272:5514-21. [PMID: 16262691 DOI: 10.1111/j.1742-4658.2005.04943.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Studies on horseradish peroxidase C and other haem peroxidases have been carried out on selected mutants in the distal haem cavity providing insight into the functional importance of the distal residues. Recent work has demonstrated that proximal structural features can also exert an important influence in determining the electronic structure of the haem pocket. To extend our understanding of the significance of proximal characteristics in regulating haem properties the proximal Thr171Ser mutant has been constructed. Thr171 is an important linking residue between the structural proximal Ca2+ ion and the proximal haem ligand, in particular the methyl group of Thr171 interdigitates with other proximal residues in the core of the enzyme. Although the mutation induces no significant changes to the functional properties of the enzyme, electronic absorption and resonance Raman spectroscopy reveal that it has a highly selective affect on the reduced state of the enzyme, effectively stabilizing it, whilst the electronic properties of the Fe(III) state unchanged and essentially identical to those of the native protein. This results in a significant change in the Fe2+/Fe3+ redox potential of the mutant. It is concluded that the unusual properties of the Thr171Ser mutant reflect the loss of a structural restraint in the proximal haem pocket that allows 'slippage' of the proximal haem ligand, but only in the reduced state. This is a remarkably subtle and specific effect that appears to increase the flexibility of the reduced state of the mutant compared to that of the wild-type protein.
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Affiliation(s)
- Barry D Howes
- Dipartimento di Chimica, Università di Firenze, Italy
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Battistuzzi G, Bellei M, Leonardi A, Pierattelli R, De Candia A, Vila AJ, Sola M. Reduction thermodynamics of the T1 Cu site in plant and fungal laccases. J Biol Inorg Chem 2005; 10:867-73. [PMID: 16231129 DOI: 10.1007/s00775-005-0035-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2005] [Accepted: 09/19/2005] [Indexed: 10/25/2022]
Abstract
The thermodynamic parameters for reduction of the type-1 (T1) copper site in Rhus vernicifera and Trametes versicolor laccases and for the derivative of the former protein from which the type-2 copper has been selectively removed (T2D) have been determined with UV-vis spectroelectrochemistry. In all cases, the enthalpic term turns out to be the main determinant of the Eo' of the T1 site. Also the difference between the reduction potentials of the two laccases is enthalpy-based and reflects differences in the coordination features of the T1 sites and their protein environment. The T1 sites in native R. vernicifera laccase and its T2D derivative show the same Eo', as a result of compensatory differences in the reduction thermodynamics. This suggests that removal of the type-2 (T2) copper results in modification of the reduction-induced solvent reorganization effects, with no influence in the structure of the multicopper protein site. This conclusion is supported by NMR data recorded on the native, the T2D, and Hg-substituted T1 derivatives of R. vernicifera laccase, which show that the T1 and T2/T3 sites are largely noninteracting.
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Affiliation(s)
- Gianantonio Battistuzzi
- Department of Chemistry-Centro SCS, University of Modena and Reggio Emilia, Via Campi 183, 41100, Modena, Italy.
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Yu P, Lin Y, Xiang L, Su L, Zhang J, Mao L. Molecular films of water-miscible ionic liquids formed on glassy carbon electrodes: characterization and electrochemical applications. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2005; 21:9000-6. [PMID: 16171322 DOI: 10.1021/la051089v] [Citation(s) in RCA: 98] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
This letter describes the formation and possible electrochemical applications of molecular films of water-miscible imidazolium-based ionic liquids (ILs) on glassy carbon (GC) electrodes. X-ray photoelectron spectroscopy (XPS) and electrochemical results indicate that the water-miscible ILs used in this study can interact with the GC electrode and form molecular films on the electrode surface. The formed molecular films are found to possess striking electrochemical properties such as electrocatalysis toward ascorbic acid (AA) and the capability to facilitate direct electron transfer of horseradish peroxidase (HRP). This demonstration would pave the way for new electrochemical applications of water-miscible ILs and is envisaged to be useful for the investigation of the electrochemical properties of water-miscible ILs in aqueous media provided the same counteranion is used as the supporting electrolyte.
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Affiliation(s)
- Ping Yu
- Center for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China
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Liu X, Huang Y, Zhang W, Fan G, Fan C, Li G. Electrochemical investigation of redox thermodynamics of immobilized myoglobin: ionic and ligation effects. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2005; 21:375-378. [PMID: 15620327 DOI: 10.1021/la047928f] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
In this study, we investigated redox thermodynamics of myoglobin as well as the ionic (phosphate ions) and ligation (imidazole) effects via a dynamic electrochemical approach. We employed a previously established system that features nonmediated, direct electrochemistry of myoglobin and myoglobin in an immobilized state (i.e., diffusionless electrochemistry). Thermodynamics parameters were obtained by measuring redox potential (E degrees ') of myoglobin at varied temperature (T), in the presence and in the absence of specific ions or axial ligands. As a step further, we evaluated contributions from allosteric effect and axial iron ligation by partitioning E degrees ' changes into entropic and enthalpic terms. Compensation phenomena between the entropic and enthalpic changes were observed in all these cases. On the basis of these studies, we also correlated these phenomena to possible structural variations.
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Affiliation(s)
- Xinjian Liu
- Department of Biochemistry and National Key Laboratory of Pharmaceutical, Biotechnology, Nanjing University, Nanjing 210093, People's Republic of China
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Battistuzzi G, Bellei M, Bortolotti CA, Rocco GD, Leonardi A, Sola M. Characterization of the solution reactivity of a basic heme peroxidase from Cucumis sativus. Arch Biochem Biophys 2004; 423:317-31. [PMID: 15001396 DOI: 10.1016/j.abb.2003.12.036] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2003] [Revised: 12/10/2003] [Indexed: 10/26/2022]
Abstract
A basic heme peroxidase has been isolated from cucumber (Cucumis sativus) peelings and characterized through electronic and (1)H NMR spectra from pH 3 to 11. The protein, as isolated, contains a high-spin ferriheme which in the low pH region is sensitive to two acid-base equilibria with apparent pK(a) values of approximately 5 and 3.6, assigned to the distal histidine and to a heme propionate, respectively. At high pH, a new low-spin species develops with an apparent pK(a) of 11, likely due to the binding of an hydroxide ion to the sixth (axial) coordination position of the Fe(III). A number of acid-base equilibria involving heme propionates and residues in the distal cavity also affect the binding of inorganic anions such as cyanide, azide, and fluoride to the ferriheme, as well as the catalytic activity. The reduction potentials of the native protein and of its cyanide derivative, determined through UV-Vis spectroelectrochemistry, result to be -0.320+/-0.015 and -0.412+/-0.010V, respectively. Overall, the reactivity of this protein parallels those of other plant peroxidases, especially horseradish peroxidase. However, some differences exist in the acid-base equilibria affecting its reactivity and in the reduction potential, likely as a result of small structural differences in the heme distal and proximal cavities.
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Affiliation(s)
- Gianantonio Battistuzzi
- Department of Chemistry, Centro SCS, University of Modena and Reggio Emilia, Via Campi 183, Modena 41100, Italy
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Khoshtariya DE, Wei J, Liu H, Yue H, Waldeck DH. Charge-transfer mechanism for cytochrome c adsorbed on nanometer thick films. Distinguishing frictional control from conformational gating. J Am Chem Soc 2003; 125:7704-14. [PMID: 12812512 DOI: 10.1021/ja034719t] [Citation(s) in RCA: 112] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Using nanometer thick tunneling barriers with specifically attached cytochrome c, the electron-transfer rate constant was studied as a function of the SAM composition (alkane versus terthiophene), the omega-terminating group type (pyridine, imidazole, nitrile), and the solution viscosity. At large electrode-reactant separations, the pyridine terminated alkanethiols exhibit an exponential decline of the rate constant with increasing electron-transfer distance. At short separations, a plateau behavior, analogous to systems involving -COOH terminal groups to which cytochrome c can be attached electrostatically, is observed. The dependence of the rate constant in the plateau region on system properties is investigated. The rate constant is insensitive to the mode of attachment to the surface but displays a significant viscosity dependence, change with spacer composition (alkane versus terthiophene), and nature of the solvent (H(2)O versus D(2)O). Based on these findings and others, the conclusion is drawn that the charge-transfer rate constant at short distance is determined by polarization relaxation processes in the structure, rather than the electron tunneling probability or large-amplitude conformational rearrangement (gating). The transition in reaction mechanism with distance reflects a gradual transition between the tunneling and frictional mechanisms. This conclusion is consistent with data from a number of other sources as well.
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