1
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Lin YW. Functional metalloenzymes based on myoglobin and neuroglobin that exploit covalent interactions. J Inorg Biochem 2024; 257:112595. [PMID: 38759262 DOI: 10.1016/j.jinorgbio.2024.112595] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2024] [Revised: 04/29/2024] [Accepted: 05/05/2024] [Indexed: 05/19/2024]
Abstract
Globins, such as myoglobin (Mb) and neuroglobin (Ngb), are ideal protein scaffolds for the design of functional metalloenzymes. To date, numerous approaches have been developed for enzyme design. This review presents a summary of the progress made in the design of functional metalloenzymes based on Mb and Ngb, with a focus on the exploitation of covalent interactions, including coordination bonds and covalent modifications. These include the construction of a metal-binding site, the incorporation of a non-native metal cofactor, the formation of Cys/Tyr-heme covalent links, and the design of disulfide bonds, as well as other Cys-covalent modifications. As exemplified by recent studies from our group and others, the designed metalloenzymes have potential applications in biocatalysis and bioconversions. Furthermore, we discuss the current trends in the design of functional metalloenzymes and highlight the importance of covalent interactions in the design of functional metalloenzymes.
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Affiliation(s)
- Ying-Wu Lin
- School of Chemistry and Chemical Engineering, University of South China, Hengyang 421001, China; Key Lab of Protein Structure and Function of Universities in Hunan Province, University of South China, Hengyang 421001, China.
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2
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Birch-Price Z, Hardy FJ, Lister TM, Kohn AR, Green AP. Noncanonical Amino Acids in Biocatalysis. Chem Rev 2024; 124:8740-8786. [PMID: 38959423 PMCID: PMC11273360 DOI: 10.1021/acs.chemrev.4c00120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2024] [Revised: 06/11/2024] [Accepted: 06/12/2024] [Indexed: 07/05/2024]
Abstract
In recent years, powerful genetic code reprogramming methods have emerged that allow new functional components to be embedded into proteins as noncanonical amino acid (ncAA) side chains. In this review, we will illustrate how the availability of an expanded set of amino acid building blocks has opened a wealth of new opportunities in enzymology and biocatalysis research. Genetic code reprogramming has provided new insights into enzyme mechanisms by allowing introduction of new spectroscopic probes and the targeted replacement of individual atoms or functional groups. NcAAs have also been used to develop engineered biocatalysts with improved activity, selectivity, and stability, as well as enzymes with artificial regulatory elements that are responsive to external stimuli. Perhaps most ambitiously, the combination of genetic code reprogramming and laboratory evolution has given rise to new classes of enzymes that use ncAAs as key catalytic elements. With the framework for developing ncAA-containing biocatalysts now firmly established, we are optimistic that genetic code reprogramming will become a progressively more powerful tool in the armory of enzyme designers and engineers in the coming years.
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Affiliation(s)
| | | | | | | | - Anthony P. Green
- Manchester Institute of Biotechnology,
School of Chemistry, University of Manchester, Manchester M1 7DN, U.K.
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3
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Chaturvedi SS, Bím D, Christov CZ, Alexandrova AN. From random to rational: improving enzyme design through electric fields, second coordination sphere interactions, and conformational dynamics. Chem Sci 2023; 14:10997-11011. [PMID: 37860658 PMCID: PMC10583697 DOI: 10.1039/d3sc02982d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2023] [Accepted: 09/11/2023] [Indexed: 10/21/2023] Open
Abstract
Enzymes are versatile and efficient biological catalysts that drive numerous cellular processes, motivating the development of enzyme design approaches to tailor catalysts for diverse applications. In this perspective, we investigate the unique properties of natural, evolved, and designed enzymes, recognizing their strengths and shortcomings. We highlight the challenges and limitations of current enzyme design protocols, with a particular focus on their limited consideration of long-range electrostatic and dynamic effects. We then delve deeper into the impact of the protein environment on enzyme catalysis and explore the roles of preorganized electric fields, second coordination sphere interactions, and protein dynamics for enzyme function. Furthermore, we present several case studies illustrating successful enzyme-design efforts incorporating enzyme strategies mentioned above to achieve improved catalytic properties. Finally, we envision the future of enzyme design research, spotlighting the challenges yet to be overcome and the synergy of intrinsic electric fields, second coordination sphere interactions, and conformational dynamics to push the state-of-the-art boundaries.
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Affiliation(s)
- Shobhit S Chaturvedi
- Department of Chemistry and Biochemistry, University of California, Los Angeles California 90095 USA
| | - Daniel Bím
- Department of Chemistry and Biochemistry, University of California, Los Angeles California 90095 USA
| | - Christo Z Christov
- Department of Chemistry, Michigan Technological University Houghton Michigan 49931 USA
| | - Anastassia N Alexandrova
- Department of Chemistry and Biochemistry, University of California, Los Angeles California 90095 USA
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4
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Yuan F, Su B, Yu Y, Wang J. Study and design of amino acid-based radical enzymes using unnatural amino acids. RSC Chem Biol 2023; 4:431-446. [PMID: 37292061 PMCID: PMC10246556 DOI: 10.1039/d2cb00250g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2022] [Accepted: 05/17/2023] [Indexed: 06/10/2023] Open
Abstract
Radical enzymes harness the power of reactive radical species by placing them in a protein scaffold, and they are capable of catalysing many important reactions. New native radical enzymes, especially those with amino acid-based radicals, in the category of non-heme iron enzymes (including ribonucleotide reductases), heme enzymes, copper enzymes, and FAD-radical enzymes have been discovered and characterized. We discussed recent research efforts to discover new native amino acid-based radical enzymes, and to study the roles of radicals in processes such as enzyme catalysis and electron transfer. Furthermore, design of radical enzymes in a small and simple scaffold not only allows us to study the radical in a well-controlled system and test our understanding of the native enzymes, but also allows us to create powerful enzymes. In the study and design of amino acid-based radical enzymes, the use of unnatural amino acids allows precise control of pKa values and reduction potentials of the residue, as well as probing the location of the radical through spectroscopic methods, making it a powerful research tool. Our understanding of amino acid-based radical enzymes will allow us to tailor them to create powerful catalysts and better therapeutics.
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Affiliation(s)
- Feiyan Yuan
- Institute of Biochemical Engineering, Key Laboratory of Medical Molecule Science and Pharmaceutical Engineering, Ministry of Industry and Information Technology, School of Chemistry and Chemical Engineering, Beijing Institute of Technology Beijing 102488 China
| | - Binbin Su
- Institute of Biochemical Engineering, Key Laboratory of Medical Molecule Science and Pharmaceutical Engineering, Ministry of Industry and Information Technology, School of Chemistry and Chemical Engineering, Beijing Institute of Technology Beijing 102488 China
| | - Yang Yu
- Institute of Biochemical Engineering, Key Laboratory of Medical Molecule Science and Pharmaceutical Engineering, Ministry of Industry and Information Technology, School of Chemistry and Chemical Engineering, Beijing Institute of Technology Beijing 102488 China
| | - Jiangyun Wang
- Laboratory of RNA Biology, Institute of Biophysics, Chinese Academy of Sciences Beijing 100101 China
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5
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Ledray AP, Dwaraknath S, Chakarawet K, Sponholtz MR, Merchen C, Van Stappen C, Rao G, Britt RD, Lu Y. Tryptophan Can Promote Oxygen Reduction to Water in a Biosynthetic Model of Heme Copper Oxidases. Biochemistry 2023; 62:388-395. [PMID: 36215733 DOI: 10.1021/acs.biochem.2c00300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Heme-copper oxidases (HCOs) utilize tyrosine (Tyr) to donate one of the four electrons required for the reduction of O2 to water in biological respiration, while tryptophan (Trp) is speculated to fulfill the same role in cyt bd oxidases. We previously engineered myoglobin into a biosynthetic model of HCOs and demonstrated the critical role that Tyr serves in the oxygen reduction reaction (ORR). To address the roles of Tyr and Trp in these oxidases, we herein report the preparation of the same biosynthetic model with the Tyr replaced by Trp and further demonstrate that Trp can also promote the ORR, albeit with lower activity. An X-ray crystal structure of the Trp variant shows a hydrogen-bonding network involving two water molecules that are organized by Trp, similar to that in the Tyr variant, which is absent in the crystal structure with the native Phe residue. Additional electron paramagnetic resonance measurements are consistent with the formation of a Trp radical species upon reacting with H2O2. We attribute the lower activity of the Trp variant to Trp's higher reduction potential relative to Tyr. Together, these findings demonstrate, for the first time, that Trp can indeed promote the ORR and provides a structural basis for the observation of varying activities. The results support a redox role for the conserved Trp in bd oxidase while suggesting that HCOs use Tyr instead of Trp to achieve higher reactivity.
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Affiliation(s)
- Aaron P Ledray
- Department of Chemistry, University of Texas at Austin, Austin, Texas 78712, United States
| | - Sudharsan Dwaraknath
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Khetpakorn Chakarawet
- Department of Chemistry, University of California, Davis, California 95616, United States
| | - Madeline R Sponholtz
- Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Claire Merchen
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Casey Van Stappen
- Department of Chemistry, University of Texas at Austin, Austin, Texas 78712, United States
| | - Guodong Rao
- Department of Chemistry, University of California, Davis, California 95616, United States
| | - R David Britt
- Department of Chemistry, University of California, Davis, California 95616, United States
| | - Yi Lu
- Department of Chemistry, University of Texas at Austin, Austin, Texas 78712, United States.,Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States.,Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
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6
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Graham JE, Niks D, Zane GM, Gui Q, Hom K, Hille R, Wall JD, Raman CS. How a Formate Dehydrogenase Responds to Oxygen: Unexpected O 2 Insensitivity of an Enzyme Harboring Tungstopterin, Selenocysteine, and [4Fe–4S] Clusters. ACS Catal 2022. [DOI: 10.1021/acscatal.2c00316] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Joel E. Graham
- Department of Pharmaceutical Sciences, University of Maryland, Baltimore, Maryland21201, United States
| | - Dimitri Niks
- Department of Biochemistry, University of California, Riverside, California92521, United States
| | - Grant M. Zane
- Department of Biochemistry, University of Missouri, Columbia, Missouri65211, United States
| | - Qin Gui
- Department of Biochemistry, University of Missouri, Columbia, Missouri65211, United States
| | - Kellie Hom
- Department of Pharmaceutical Sciences, University of Maryland, Baltimore, Maryland21201, United States
| | - Russ Hille
- Department of Biochemistry, University of California, Riverside, California92521, United States
| | - Judy D. Wall
- Department of Biochemistry, University of Missouri, Columbia, Missouri65211, United States
| | - C. S. Raman
- Department of Pharmaceutical Sciences, University of Maryland, Baltimore, Maryland21201, United States
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7
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Van Stappen C, Deng Y, Liu Y, Heidari H, Wang JX, Zhou Y, Ledray AP, Lu Y. Designing Artificial Metalloenzymes by Tuning of the Environment beyond the Primary Coordination Sphere. Chem Rev 2022; 122:11974-12045. [PMID: 35816578 DOI: 10.1021/acs.chemrev.2c00106] [Citation(s) in RCA: 32] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Metalloenzymes catalyze a variety of reactions using a limited number of natural amino acids and metallocofactors. Therefore, the environment beyond the primary coordination sphere must play an important role in both conferring and tuning their phenomenal catalytic properties, enabling active sites with otherwise similar primary coordination environments to perform a diverse array of biological functions. However, since the interactions beyond the primary coordination sphere are numerous and weak, it has been difficult to pinpoint structural features responsible for the tuning of activities of native enzymes. Designing artificial metalloenzymes (ArMs) offers an excellent basis to elucidate the roles of these interactions and to further develop practical biological catalysts. In this review, we highlight how the secondary coordination spheres of ArMs influence metal binding and catalysis, with particular focus on the use of native protein scaffolds as templates for the design of ArMs by either rational design aided by computational modeling, directed evolution, or a combination of both approaches. In describing successes in designing heme, nonheme Fe, and Cu metalloenzymes, heteronuclear metalloenzymes containing heme, and those ArMs containing other metal centers (including those with non-native metal ions and metallocofactors), we have summarized insights gained on how careful controls of the interactions in the secondary coordination sphere, including hydrophobic and hydrogen bonding interactions, allow the generation and tuning of these respective systems to approach, rival, and, in a few cases, exceed those of native enzymes. We have also provided an outlook on the remaining challenges in the field and future directions that will allow for a deeper understanding of the secondary coordination sphere a deeper understanding of the secondary coordintion sphere to be gained, and in turn to guide the design of a broader and more efficient variety of ArMs.
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Affiliation(s)
- Casey Van Stappen
- Department of Chemistry, University of Texas at Austin, 105 East 24th Street, Austin, Texas 78712, United States
| | - Yunling Deng
- Department of Chemistry, University of Texas at Austin, 105 East 24th Street, Austin, Texas 78712, United States
| | - Yiwei Liu
- Department of Chemistry, University of Illinois, Urbana-Champaign, 505 South Mathews Avenue, Urbana, Illinois 61801, United States
| | - Hirbod Heidari
- Department of Chemistry, University of Texas at Austin, 105 East 24th Street, Austin, Texas 78712, United States
| | - Jing-Xiang Wang
- Department of Chemistry, University of Texas at Austin, 105 East 24th Street, Austin, Texas 78712, United States
| | - Yu Zhou
- Department of Chemistry, University of Texas at Austin, 105 East 24th Street, Austin, Texas 78712, United States
| | - Aaron P Ledray
- Department of Chemistry, University of Texas at Austin, 105 East 24th Street, Austin, Texas 78712, United States
| | - Yi Lu
- Department of Chemistry, University of Texas at Austin, 105 East 24th Street, Austin, Texas 78712, United States.,Department of Chemistry, University of Illinois, Urbana-Champaign, 505 South Mathews Avenue, Urbana, Illinois 61801, United States
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8
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Marianov AN, Kochubei AS, Gu S, Jiang Y. Charge-Transfer Mechanism in Oxygen Reduction over Co Porphyrins: Single-Site Molecular Electrocatalysts to Macromolecular Frameworks. ACS Catal 2022. [DOI: 10.1021/acscatal.2c00847] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Affiliation(s)
| | - Alena S. Kochubei
- School of Engineering, Macquarie University, Sydney, NSW 2109, Australia
| | - Shengshen Gu
- School of Engineering, Macquarie University, Sydney, NSW 2109, Australia
| | - Yijiao Jiang
- School of Engineering, Macquarie University, Sydney, NSW 2109, Australia
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9
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Nayek A, Ahmed ME, Samanta S, Dinda S, Patra S, Dey SG, Dey A. Bioinorganic Chemistry on Electrodes: Methods to Functional Modeling. J Am Chem Soc 2022; 144:8402-8429. [PMID: 35503922 DOI: 10.1021/jacs.2c01842] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
One of the major goals of bioinorganic chemistry has been to mimic the function of elegant metalloenzymes. Such functional modeling has been difficult to attain in solution, in particular, for reactions that require multiple protons and multiple electrons (nH+/ne-). Using a combination of heterogeneous electrochemistry, electrode and molecule design one may control both electron transfer (ET) and proton transfer (PT) of these nH+/ne- reactions. Such control can allow functional modeling of hydrogenases (H+ + e- → 1/2 H2), cytochrome c oxidase (O2 + 4 e- + 4 H+ → 2 H2O), monooxygenases (RR'CH2 + O2 + 2 e- + 2 H+ → RR'CHOH + H2O) and dioxygenases (S + O2 → SO2; S = organic substrate) in aqueous medium and at room temperatures. In addition, these heterogeneous constructs allow probing unnatural bioinspired reactions and estimation of the inner- and outer-sphere reorganization energy of small molecules and proteins.
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Affiliation(s)
- Abhijit Nayek
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2A Raja SC Mullick Road, Kolkata, WB India 700032
| | - Md Estak Ahmed
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2A Raja SC Mullick Road, Kolkata, WB India 700032
| | - Soumya Samanta
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2A Raja SC Mullick Road, Kolkata, WB India 700032
| | - Souvik Dinda
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2A Raja SC Mullick Road, Kolkata, WB India 700032
| | - Suman Patra
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2A Raja SC Mullick Road, Kolkata, WB India 700032
| | - Somdatta Ghosh Dey
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2A Raja SC Mullick Road, Kolkata, WB India 700032
| | - Abhishek Dey
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2A Raja SC Mullick Road, Kolkata, WB India 700032
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10
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Bhunia S, Ghatak A, Dey A. Second Sphere Effects on Oxygen Reduction and Peroxide Activation by Mononuclear Iron Porphyrins and Related Systems. Chem Rev 2022; 122:12370-12426. [PMID: 35404575 DOI: 10.1021/acs.chemrev.1c01021] [Citation(s) in RCA: 35] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Activation and reduction of O2 and H2O2 by synthetic and biosynthetic iron porphyrin models have proved to be a versatile platform for evaluating second-sphere effects deemed important in naturally occurring heme active sites. Advances in synthetic techniques have made it possible to install different functional groups around the porphyrin ligand, recreating artificial analogues of the proximal and distal sites encountered in the heme proteins. Using judicious choices of these substituents, several of the elegant second-sphere effects that are proposed to be important in the reactivity of key heme proteins have been evaluated under controlled environments, adding fundamental insight into the roles played by these weak interactions in nature. This review presents a detailed description of these efforts and how these have not only demystified these second-sphere effects but also how the knowledge obtained resulted in functional mimics of these heme enzymes.
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Affiliation(s)
- Sarmistha Bhunia
- School of Chemical Science, Indian Association for the Cultivation of Science, 2A Raja SC Mullick Road, Kolkata 700032, India
| | - Arnab Ghatak
- School of Chemical Science, Indian Association for the Cultivation of Science, 2A Raja SC Mullick Road, Kolkata 700032, India
| | - Abhishek Dey
- School of Chemical Science, Indian Association for the Cultivation of Science, 2A Raja SC Mullick Road, Kolkata 700032, India
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11
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Stein A, Liang AD, Sahin R, Ward TR. Incorporation of Metal-Chelating Unnatural Amino Acids into HaloTag for Allylic Deamination. J Organomet Chem 2022. [DOI: 10.1016/j.jorganchem.2022.122272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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12
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Mukherjee M, Dey A. Rejigging Electron and Proton Transfer to Transition between Dioxygenase, Monooxygenase, Peroxygenase, and Oxygen Reduction Activity: Insights from Bioinspired Constructs of Heme Enzymes. JACS AU 2021; 1:1296-1311. [PMID: 34604840 PMCID: PMC8479764 DOI: 10.1021/jacsau.1c00100] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Indexed: 05/10/2023]
Abstract
Nature has employed heme proteins to execute a diverse set of vital life processes. Years of research have been devoted to understanding the factors which bias these heme enzymes, with all having a heme cofactor, toward distinct catalytic activity. Among them, axial ligation, distal super structure, and substrate binding pockets are few very vividly recognized ones. Detailed mechanistic investigation of these heme enzymes suggested that several of these enzymes, while functionally divergent, use similar intermediates. Furthermore, the formation and decay of these intermediates depend on proton and electron transfer processes in the enzyme active site. Over the past decade, work in this group, using in situ surface enhanced resonance Raman spectroscopy of synthetic and biosynthetic analogues of heme enzymes, a general idea of how proton and electron transfer rates relate to the lifetime of different O2 derived intermediates has been developed. These findings suggest that the enzymatic activities of all these heme enzymes can be integrated into one general cycle which can be branched out to different catalytic pathways by regulating the lifetime and population of each of these intermediates. This regulation can further be achieved by tuning the electron and proton transfer steps. By strategically populating one of these intermediates during oxygen reduction, one can navigate through different catalytic processes to a desired direction by altering proton and electron transfer steps.
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Affiliation(s)
- Manjistha Mukherjee
- School of Chemical Science, Indian Association for the Cultivation of Science, 2A Raja SC Mullick Road, Kolkata, WB India, 700032
| | - Abhishek Dey
- School of Chemical Science, Indian Association for the Cultivation of Science, 2A Raja SC Mullick Road, Kolkata, WB India, 700032
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13
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Jung SM, Lee J, Song WJ. Design of artificial metalloenzymes with multiple inorganic elements: The more the merrier. J Inorg Biochem 2021; 223:111552. [PMID: 34332336 DOI: 10.1016/j.jinorgbio.2021.111552] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2021] [Revised: 06/21/2021] [Accepted: 07/15/2021] [Indexed: 11/27/2022]
Abstract
A large fraction of metalloenzymes harbors multiple metal-centers that are electronically and/or functionally arranged within their proteinaceous environments. To explore the orchestration of inorganic and biochemical components and to develop bioinorganic catalysts and materials, we have described selected examples of artificial metalloproteins having multiple metallocofactors that were grouped depending on their initial protein scaffolds, the nature of introduced inorganic moieties, and the method used to propagate the number of metal ions within a protein. They demonstrated that diverse inorganic moieties can be selectively grafted and modulated in protein environments, providing a retrosynthetic bottom-up approach in the design of versatile and proficient biocatalysts and biomimetic model systems to explore fundamental questions in bioinorganic chemistry.
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Affiliation(s)
- Se-Min Jung
- Department of Chemistry, College of Natural Sciences, Seoul National University, Seoul 08826, Republic of Korea
| | - Jaehee Lee
- Department of Chemistry, College of Natural Sciences, Seoul National University, Seoul 08826, Republic of Korea
| | - Woon Ju Song
- Department of Chemistry, College of Natural Sciences, Seoul National University, Seoul 08826, Republic of Korea.
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14
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Xiang HF, Xu JK, Liu J, Yang XZ, Gao SQ, Wen GB, Lin YW. Efficient biodegradation of malachite green by an artificial enzyme designed in myoglobin. RSC Adv 2021; 11:16090-16095. [PMID: 35481174 PMCID: PMC9029994 DOI: 10.1039/d1ra02202d] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Accepted: 04/25/2021] [Indexed: 12/26/2022] Open
Abstract
Synthetic dyes such as malachite green (MG) have a wide range of applications. Meanwhile, they bring great challenges for environmental security and cause potential damages to human health. Compared with traditional approaches, enzymatic catalysis is an emerging technique for wastewater treatment. As alternatives to natural enzymes, artificial enzymes have received much attention for potential applications. In previous studies, we have rationally designed artificial enzymes based on myoglobin (Mb), such as by introducing a distal histidine (F43H mutation) and creating a channel to the heme pocket (H64A mutation). We herein show that the artificial enzyme of F43H/H64A Mb can be successfully applied for efficient biodegradation of MG under weak acid conditions. The degradation efficiency is much higher than those of natural enzymes, such as dye-decolorizing peroxidase and laccase (13-18-fold). The interaction of MG and F43H/H64A Mb was investigated by using both experimental and molecular docking studies, and the biodegradation products of MG were also revealed by UPLC-ESI-MS analysis. Based on these results, we proposed a plausible biodegradation mechanism of MG. With the high-yield of overexpression in E. coli cells, this study suggests that the artificial enzyme has potential applications in the biodegradation of MG in fisheries and textile industries.
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Affiliation(s)
- Heng-Fang Xiang
- School of Chemistry and Chemical Engineering, University of South China Hengyang 421001 China
| | - Jia-Kun Xu
- Key Lab of Sustainable Development of Polar Fisheries, Ministry of Agriculture and Rural Affairs, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Lab for Marine Drugs and Byproducts of Pilot National Lab for Marine Science and Technology Qingdao 266071 China
| | - Jiao Liu
- School of Chemistry and Chemical Engineering, University of South China Hengyang 421001 China
| | - Xin-Zhi Yang
- Laboratory of Protein Structure and Function, University of South China Medical School Hengyang 421001 China
| | - Shu-Qin Gao
- Laboratory of Protein Structure and Function, University of South China Medical School Hengyang 421001 China
| | - Ge-Bo Wen
- Laboratory of Protein Structure and Function, University of South China Medical School Hengyang 421001 China
| | - Ying-Wu Lin
- School of Chemistry and Chemical Engineering, University of South China Hengyang 421001 China
- Laboratory of Protein Structure and Function, University of South China Medical School Hengyang 421001 China
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15
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De novo biosynthesis of a nonnatural cobalt porphyrin cofactor in E. coli and incorporation into hemoproteins. Proc Natl Acad Sci U S A 2021; 118:2017625118. [PMID: 33850014 DOI: 10.1073/pnas.2017625118] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Enzymes that bear a nonnative or artificially introduced metal center can engender novel reactivity and enable new spectroscopic and structural studies. In the case of metal-organic cofactors, such as metalloporphyrins, no general methods exist to build and incorporate new-to-nature cofactor analogs in vivo. We report here that a common laboratory strain, Escherichia coli BL21(DE3), biosynthesizes cobalt protoporphyrin IX (CoPPIX) under iron-limited, cobalt-rich growth conditions. In supplemented minimal media containing CoCl2, the metabolically produced CoPPIX is directly incorporated into multiple hemoproteins in place of native heme b (FePPIX). Five cobalt-substituted proteins were successfully expressed with this new-to-nature cobalt porphyrin cofactor: myoglobin H64V V68A, dye decolorizing peroxidase, aldoxime dehydratase, cytochrome P450 119, and catalase. We show conclusively that these proteins incorporate CoPPIX, with the CoPPIX making up at least 95% of the total porphyrin content. In cases in which the native metal ligand is a sulfur or nitrogen, spectroscopic parameters are consistent with retention of native metal ligands. This method is an improvement on previous approaches with respect to both yield and ease-of-implementation. Significantly, this method overcomes a long-standing challenge to incorporate nonnatural cofactors through de novo biosynthesis. By utilizing a ubiquitous laboratory strain, this process will facilitate spectroscopic studies and the development of enzymes for CoPPIX-mediated biocatalysis.
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16
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DiPrimio DJ, Holland PL. Repurposing metalloproteins as mimics of natural metalloenzymes for small-molecule activation. J Inorg Biochem 2021; 219:111430. [PMID: 33873051 DOI: 10.1016/j.jinorgbio.2021.111430] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2020] [Revised: 03/11/2021] [Accepted: 03/15/2021] [Indexed: 12/12/2022]
Abstract
Artificial metalloenzymes (ArMs) consist of an unnatural metal or cofactor embedded in a protein scaffold, and are an excellent platform for applying the concepts of protein engineering to catalysis. In this Focused Review, we describe the application of ArMs as simple, tunable artificial models of the active sites of complex natural metalloenzymes for small-molecule activation. In this sense, ArMs expand the strategies of synthetic model chemistry to protein-based supporting ligands with potential for participation from the second coordination sphere. We focus specifically on ArMs that are structural, spectroscopic, and functional models of enzymes for activation of small molecules like CO, CO2, O2, N2, and NO, as well as production/consumption of H2. These ArMs give insight into the identities and roles of metalloenzyme structural features within and near the cofactor. We give examples of ArM work relevant to hydrogenases, acetyl-coenzyme A synthase, superoxide dismutase, heme oxygenases, nitric oxide reductase, methyl-coenzyme M reductase, copper-O2 enzymes, and nitrogenases.
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Affiliation(s)
- Daniel J DiPrimio
- Department of Chemistry, Yale University, New Haven, CT, 06520, United States
| | - Patrick L Holland
- Department of Chemistry, Yale University, New Haven, CT, 06520, United States.
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Naowarojna N, Cheng R, Lopez J, Wong C, Qiao L, Liu P. Chemical modifications of proteins and their applications in metalloenzyme studies. Synth Syst Biotechnol 2021; 6:32-49. [PMID: 33665390 PMCID: PMC7897936 DOI: 10.1016/j.synbio.2021.01.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Revised: 12/14/2020] [Accepted: 01/03/2021] [Indexed: 12/21/2022] Open
Abstract
Protein chemical modifications are important tools for elucidating chemical and biological functions of proteins. Several strategies have been developed to implement these modifications, including enzymatic tailoring reactions, unnatural amino acid incorporation using the expanded genetic codes, and recognition-driven transformations. These technologies have been applied in metalloenzyme studies, specifically in dissecting their mechanisms, improving their enzymatic activities, and creating artificial enzymes with non-natural activities. Herein, we summarize some of the recent efforts in these areas with an emphasis on a few metalloenzyme case studies.
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Affiliation(s)
| | | | - Juan Lopez
- Department of Chemistry, Boston University, Boston, MA, 02215, United States
| | - Christina Wong
- Department of Chemistry, Boston University, Boston, MA, 02215, United States
| | - Lu Qiao
- Department of Chemistry, Boston University, Boston, MA, 02215, United States
| | - Pinghua Liu
- Department of Chemistry, Boston University, Boston, MA, 02215, United States
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18
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Reed CJ, Lam QN, Mirts EN, Lu Y. Molecular understanding of heteronuclear active sites in heme-copper oxidases, nitric oxide reductases, and sulfite reductases through biomimetic modelling. Chem Soc Rev 2021; 50:2486-2539. [PMID: 33475096 PMCID: PMC7920998 DOI: 10.1039/d0cs01297a] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Heme-copper oxidases (HCO), nitric oxide reductases (NOR), and sulfite reductases (SiR) catalyze the multi-electron and multi-proton reductions of O2, NO, and SO32-, respectively. Each of these reactions is important to drive cellular energy production through respiratory metabolism and HCO, NOR, and SiR evolved to contain heteronuclear active sites containing heme/copper, heme/nonheme iron, and heme-[4Fe-4S] centers, respectively. The complexity of the structures and reactions of these native enzymes, along with their large sizes and/or membrane associations, make it challenging to fully understand the crucial structural features responsible for the catalytic properties of these active sites. In this review, we summarize progress that has been made to better understand these heteronuclear metalloenzymes at the molecular level though study of the native enzymes along with insights gained from biomimetic models comprising either small molecules or proteins. Further understanding the reaction selectivity of these enzymes is discussed through comparisons of their similar heteronuclear active sites, and we offer outlook for further investigations.
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Affiliation(s)
- Christopher J Reed
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urban, IL 61801, USA.
| | - Quan N Lam
- Department of Biochemistry, University of Illinois at Urbana-Champaign, Urban, IL 61801, USA
| | - Evan N Mirts
- Center for Biophysics and Quantitative Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA and Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Yi Lu
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urban, IL 61801, USA. and Department of Biochemistry, University of Illinois at Urbana-Champaign, Urban, IL 61801, USA and Center for Biophysics and Quantitative Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA and Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
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19
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Petrik ID, Davydov R, Kahle M, Sandoval B, Dwaraknath S, Ädelroth P, Hoffman B, Lu Y. An Engineered Glutamate in Biosynthetic Models of Heme-Copper Oxidases Drives Complete Product Selectivity by Tuning the Hydrogen-Bonding Network. Biochemistry 2021; 60:346-355. [PMID: 33464878 PMCID: PMC7888536 DOI: 10.1021/acs.biochem.0c00852] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Efficiently carrying out the oxygen reduction reaction (ORR) is critical for many applications in biology and chemistry, such as bioenergetics and fuel cells, respectively. In biology, this reaction is carried out by large, transmembrane oxidases such as heme-copper oxidases (HCOs) and cytochrome bd oxidases. Common to these oxidases is the presence of a glutamate residue next to the active site, but its precise role in regulating the oxidase activity remains unclear. To gain insight into its role, we herein report that incorporation of glutamate next to a designed heme-copper center in two biosynthetic models of HCOs improves O2 binding affinity, facilitates protonation of reaction intermediates, and eliminates release of reactive oxygen species. High-resolution crystal structures of the models revealed extended, water-mediated hydrogen-bonding networks involving the glutamate. Electron paramagnetic resonance of the cryoreduced oxy-ferrous centers at cryogenic temperature followed by thermal annealing allowed observation of the key hydroperoxo intermediate that can be attributed to the hydrogen-bonding network. By demonstrating these important roles of glutamate in oxygen reduction biochemistry, this work offers deeper insights into its role in native oxidases, which may guide the design of more efficient artificial ORR enzymes or catalysts for applications such as fuel cells.
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Affiliation(s)
- Igor D. Petrik
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Roman Davydov
- The Department of Chemistry, Northwestern University, Evanston, Illinois 60201
| | - Maximilian Kahle
- Department of Biochemistry and Biophysics, Arrhenius Laboratories for Natural Sciences, Stockholm University, SE-106 91 Stockholm, Sweden
| | - Braddock Sandoval
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Sudharsan Dwaraknath
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Pia Ädelroth
- Department of Biochemistry and Biophysics, Arrhenius Laboratories for Natural Sciences, Stockholm University, SE-106 91 Stockholm, Sweden
| | - Brian Hoffman
- The Department of Chemistry, Northwestern University, Evanston, Illinois 60201
| | - Yi Lu
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
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20
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Liao F, Xu JK, Luo J, Gao SQ, Wang XJ, Lin YW. Bioinspired design of an artificial peroxidase: introducing key residues of native peroxidases into F43Y myoglobin with a Tyr-heme cross-link. Dalton Trans 2020; 49:5029-5033. [PMID: 32236202 DOI: 10.1039/d0dt00875c] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Inspired by the structural features of native peroxidases, an artificial peroxidase was rationally designed using F43Y myoglobin with a Tyr-heme cross-link by further introduction of key residues, including both a distal Arg and a Trp close to the heme group, which exhibits an enhanced peroxidase activity similar to the most efficient native horseradish peroxidase. This study provides a simple approach for design of artificial heme enzymes by the combination of catalytic elements of native enzymes with the post-translational modifications of heme proteins.
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Affiliation(s)
- Fei Liao
- School of Chemistry and Chemical Engineering, University of South China, Hengyang 421001, China.
| | - Jia-Kun Xu
- Key Lab of Sustainable Development of Polar Fisheries, Ministry of Agriculture and Rural Affairs, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Lab for Marine Drugs and By products of Pilot National Lab for Marine Science and Technology, Qingdao 266071, China
| | - Jie Luo
- School of Chemistry and Chemical Engineering, University of South China, Hengyang 421001, China.
| | - Shu-Qin Gao
- Laboratory of Protein Structure and Function, University of South China, Hengyang 421001, China
| | - Xiao-Juan Wang
- Key Lab of Sustainable Development of Polar Fisheries, Ministry of Agriculture and Rural Affairs, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Lab for Marine Drugs and By products of Pilot National Lab for Marine Science and Technology, Qingdao 266071, China
| | - Ying-Wu Lin
- School of Chemistry and Chemical Engineering, University of South China, Hengyang 421001, China. and Laboratory of Protein Structure and Function, University of South China, Hengyang 421001, China
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21
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Nazemi Z, Prasad P, Chakraborty S. Kinetics of Oxygen Reduction by a Beta Barrel Heme Protein on Hyrid Bioelectrodes. ChemElectroChem 2020. [DOI: 10.1002/celc.201901945] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Zahra Nazemi
- Department of Chemistry and BiochemistryUniversity of Mississippi, University Mississippi MS 38677 USA
| | - Pallavi Prasad
- Department of Chemistry and BiochemistryUniversity of Mississippi, University Mississippi MS 38677 USA
| | - Saumen Chakraborty
- Department of Chemistry and BiochemistryUniversity of Mississippi, University Mississippi MS 38677 USA
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22
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Engineering Metalloprotein Functions in Designed and Native Scaffolds. Trends Biochem Sci 2019; 44:1022-1040. [DOI: 10.1016/j.tibs.2019.06.006] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Revised: 06/05/2019] [Accepted: 06/11/2019] [Indexed: 12/15/2022]
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23
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Lin YW. Rational Design of Artificial Metalloproteins and Metalloenzymes with Metal Clusters. Molecules 2019; 24:E2743. [PMID: 31362341 PMCID: PMC6696605 DOI: 10.3390/molecules24152743] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Revised: 07/24/2019] [Accepted: 07/26/2019] [Indexed: 01/22/2023] Open
Abstract
Metalloproteins and metalloenzymes play important roles in biological systems by using the limited metal ions, complexes, and clusters that are associated with the protein matrix. The design of artificial metalloproteins and metalloenzymes not only reveals the structure and function relationship of natural proteins, but also enables the synthesis of artificial proteins and enzymes with improved properties and functions. Acknowledging the progress in rational design from single to multiple active sites, this review focuses on recent achievements in the design of artificial metalloproteins and metalloenzymes with metal clusters, including zinc clusters, cadmium clusters, iron-sulfur clusters, and copper-sulfur clusters, as well as noble metal clusters and others. These metal clusters were designed in both native and de novo protein scaffolds for structural roles, electron transfer, or catalysis. Some synthetic metal clusters as functional models of native enzymes are also discussed. These achievements provide valuable insights for deep understanding of the natural proteins and enzymes, and practical clues for the further design of artificial enzymes with functions comparable or even beyond those of natural counterparts.
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Affiliation(s)
- Ying-Wu Lin
- School of Chemistry and Chemical Engineering, University of South China, Hengyang 421001, China.
- Laboratory of Protein Structure and Function, University of South China, Hengyang 421001, China.
- Hunan Key Laboratory for the Design and Application of Actinide Complexes, University of South China, Hengyang 421001, China.
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24
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Selvan D, Prasad P, Farquhar ER, Shi Y, Crane S, Zhang Y, Chakraborty S. Redesign of a Copper Storage Protein into an Artificial Hydrogenase. ACS Catal 2019; 9:5847-5859. [PMID: 31341700 DOI: 10.1021/acscatal.9b00360] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
We report the construction of an artificial hydrogenase (ArH) by reengineering a Cu storage protein (Cspl) into a Ni-binding protein (NBP) employing rational metalloprotein design. The hypothesis driven design approach involved deleting existing Cu sites of Csp1 and identification of a target tetrathiolate Ni binding site within the protein scaffold followed by repacking the hydrophobic core. Guided by modeling, the NBP was expressed and purified in high purity. NBP is a well-folded and stable construct displaying native-like unfolding behavior. Spectroscopic and computational studies indicated that the NBP bound nickel in a distorted square planar geometry that validated the design. Ni(II)-NBP is active for photo-induced H2 evolution following a reductive quenching mechanism. Ni(II)-NBP catalyzed H+ reduction to H2 gas electrochemically as well. Analysis of the catalytic voltammograms established a proton-coupled electron transfer (PCET) mechanism. Electrolysis studies confirmed H2 evolution with quantitative Faradaic yields. Our studies demonstrate an important scope of rational metalloprotein design that allows imparting functions into protein scaffolds that have natively not evolved to possess the same function of the target metalloprotein constructs.
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Affiliation(s)
- Dhanashree Selvan
- Department of Chemistry and Biochemistry, University of Mississippi, University, Mississippi 38677, United States
| | - Pallavi Prasad
- Department of Chemistry and Biochemistry, University of Mississippi, University, Mississippi 38677, United States
| | - Erik R. Farquhar
- Case Western Reserve University Center for Synchrotron Biosciences, NSLS-II, Brookhaven National Laboratory, Upton, New York 11973, United States
| | - Yelu Shi
- Department of Chemistry and Chemical Biology, Stevens Institute of Technology, 1 Castle Point on Hudson, Hoboken, New Jersey 07030, United States
| | - Skyler Crane
- Department of Chemistry and Biochemistry, University of Mississippi, University, Mississippi 38677, United States
| | - Yong Zhang
- Department of Chemistry and Chemical Biology, Stevens Institute of Technology, 1 Castle Point on Hudson, Hoboken, New Jersey 07030, United States
| | - Saumen Chakraborty
- Department of Chemistry and Biochemistry, University of Mississippi, University, Mississippi 38677, United States
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25
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Ehudin MA, Senft L, Franke A, Ivanović-Burmazović I, Karlin KD. Formation and Reactivity of New Isoporphyrins: Implications for Understanding the Tyr-His Cross-Link Cofactor Biogenesis in Cytochrome c Oxidase. J Am Chem Soc 2019; 141:10632-10643. [PMID: 31150209 DOI: 10.1021/jacs.9b01791] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Cytochrome c oxidase (CcO) catalyzes the reduction of dioxygen to water utilizing a heterobinuclear active site composed of a heme moiety and a mononuclear copper center coordinated to three histidine residues, one of which is covalently cross-linked to a tyrosine residue via a post-translational modification (PTM). Although this tyrosine-histidine moiety has functional and structural importance, the pathway behind this net oxidative C-N bond coupling is still unknown. A novel route employing an iron(III) meso-substituted isoporphyrin derivative, isoelectronic with Cmpd-I ((Por•+)FeIV═O), is for the first time proposed to be a key intermediate in the Tyr-His cofactor biogenesis. Newly synthesized iron(III) meso-substituted isoporphyrins were prepared with azide, cyanide, and substituted imidazole functionalities, by adding nucleophiles to an iron(III) π-dication species formed via addition of trifluoroacetic acid to F8Cmpd-I (F8 = (tetrakis(2,6-difluorophenyl)porphyrinate)). Isoporphyrin derivatives were characterized at cryogenic temperatures via ESI-MS and UV-vis, 2H NMR, and EPR spectroscopies. Addition of 1,3,5-trimethoxybenzene or 4-methoxyphenol to the imidazole-substituted isoporphyrin led to formation of the organic product containing the imidazole coupled to aromatic substrate via a new C-N bond, as detected via cryo-ESI-MS. Experimental evidence for the formation of an imidazole-substituted isoporphyrin and its promising reactivity to form the imidazole-phenol coupled product yields viability to the herein proposed pathway behind the PTM (i.e., biogenesis) leading to the key covalent Tyr-His cross-link in CcO.
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Affiliation(s)
- Melanie A Ehudin
- Department of Chemistry , Johns Hopkins University , Baltimore , Maryland 21218 , United States
| | - Laura Senft
- Department of Chemistry and Pharmacy , Friedrich-Alexander University Erlangen-Nuremberg , 91058 Erlangen , Germany
| | - Alicja Franke
- Department of Chemistry and Pharmacy , Friedrich-Alexander University Erlangen-Nuremberg , 91058 Erlangen , Germany
| | - Ivana Ivanović-Burmazović
- Department of Chemistry and Pharmacy , Friedrich-Alexander University Erlangen-Nuremberg , 91058 Erlangen , Germany
| | - Kenneth D Karlin
- Department of Chemistry , Johns Hopkins University , Baltimore , Maryland 21218 , United States
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26
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Mirts EN, Bhagi-Damodaran A, Lu Y. Understanding and Modulating Metalloenzymes with Unnatural Amino Acids, Non-Native Metal Ions, and Non-Native Metallocofactors. Acc Chem Res 2019; 52:935-944. [PMID: 30912643 DOI: 10.1021/acs.accounts.9b00011] [Citation(s) in RCA: 93] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Metalloproteins set the gold standard for performing important functions, including catalyzing demanding reactions under mild conditions. Designing artificial metalloenzymes (ArMs) to catalyze abiological reactions has been a major endeavor for many years, but most ArM activities are far below those of native enzymes, making them unsuitable for most pratical applications. A critical step to advance the field is to fundamentally understand what it takes to not only confer but also fine-tune ArM activities so they match those of native enzymes. Indeed, only once we can freely modulate ArM activity to rival (or surpass!) natural enzymes can the potential of ArMs be fully realized. A key to unlocking ArM potential is the observation that one metal primary coordination sphere can display a range of functions and levels of activity, leading to the realization that secondary coordination sphere (SCS) interactions are critically important. However, SCS interactions are numerous, long-range, and weak, making them very difficult to reproduce in ArMs. Furthermore, natural enzymes are tied to a small set of biologically available functional moieties from canonical amino acids and physiologically available metal ions and metallocofactors, severely limiting the chemical space available to probe and tune ArMs. In this Account, we summarize the use of unnatural amino acids (UAAs) and non-native metal ions and metallocofactors by our group and our collaborators to probe and modulate ArM functions. We incorporated isostructural UAAs in a type 1 copper (T1Cu) protein azurin to provide conclusive evidence that axial ligand hydrophobicity is a major determinant of T1Cu redunction potential ( E°'). Closely related work from other groups are also discussed. We also probed the role of protein backbone interactions that cannot be altered by standard mutagenesis by replacing the peptide bond with an ester linkage. We used insight gained from these studies to tune the E°' of azurin across the entire physiological range, the broadest range ever achieved in a single metalloprotein. Introducing UAA analogues of Tyr into ArM models of heme-copper oxidase (HCO) revealed a linear relationship between p Ka, E°', and activity. We also substituted non-native hemes and non-native metal ions for their native equivalents in these models to resolve several issues that were intractable in native HCOs and the closely related nitric oxide reductases, such as their roles in modulating substrate affinity, electron transfer rate, and activity. We incorporated abiological cofactors such as ferrocene and Mn(salen) into azurin and myoglobin, respectively, to stabilize these inorganic and organometallic compounds in water, confer abiological functions, tune their E°' and activity through SCS interactions, and show that the approach to metallocofactor anchoring and orientation can tune enantioselectivity and alter function. Replacing Cu in azurin with non-native Fe or Ni can impart novel activities, such as superoxide reduction and C-C bond formation. While progress was made, we have identified only a small fraction of the interactions that can be generally applied to ArMs to fine-tune their functions. Because SCS interactions are subtle and heavily interconnected, it has been difficult to characterize their effects quantitatively. It is vital to develop spectroscopic and computational techniques to detect and quantify their effects in both resting states and catalytic intermediates.
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Affiliation(s)
- Evan N. Mirts
- Department of Chemistry and Center for Biophysics and Quantitative Biology, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801, United States
| | - Ambika Bhagi-Damodaran
- Department of Chemistry and Center for Biophysics and Quantitative Biology, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801, United States
| | - Yi Lu
- Department of Chemistry and Center for Biophysics and Quantitative Biology, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801, United States
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27
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Sinha S, Ghosh M, Warren JJ. Changing the Selectivity of O2 Reduction Catalysis with One Ligand Heteroatom. ACS Catal 2019. [DOI: 10.1021/acscatal.8b04757] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Soumalya Sinha
- Department of Chemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada
| | - Moumita Ghosh
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, Nadia, West Bengal 741246, India
| | - Jeffrey J. Warren
- Department of Chemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada
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28
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Adam SM, Wijeratne GB, Rogler PJ, Diaz DE, Quist DA, Liu JJ, Karlin KD. Synthetic Fe/Cu Complexes: Toward Understanding Heme-Copper Oxidase Structure and Function. Chem Rev 2018; 118:10840-11022. [PMID: 30372042 PMCID: PMC6360144 DOI: 10.1021/acs.chemrev.8b00074] [Citation(s) in RCA: 145] [Impact Index Per Article: 24.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Heme-copper oxidases (HCOs) are terminal enzymes on the mitochondrial or bacterial respiratory electron transport chain, which utilize a unique heterobinuclear active site to catalyze the 4H+/4e- reduction of dioxygen to water. This process involves a proton-coupled electron transfer (PCET) from a tyrosine (phenolic) residue and additional redox events coupled to transmembrane proton pumping and ATP synthesis. Given that HCOs are large, complex, membrane-bound enzymes, bioinspired synthetic model chemistry is a promising approach to better understand heme-Cu-mediated dioxygen reduction, including the details of proton and electron movements. This review encompasses important aspects of heme-O2 and copper-O2 (bio)chemistries as they relate to the design and interpretation of small molecule model systems and provides perspectives from fundamental coordination chemistry, which can be applied to the understanding of HCO activity. We focus on recent advancements from studies of heme-Cu models, evaluating experimental and computational results, which highlight important fundamental structure-function relationships. Finally, we provide an outlook for future potential contributions from synthetic inorganic chemistry and discuss their implications with relevance to biological O2-reduction.
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Affiliation(s)
- Suzanne M. Adam
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Gayan B. Wijeratne
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Patrick J. Rogler
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Daniel E. Diaz
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - David A. Quist
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Jeffrey J. Liu
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Kenneth D. Karlin
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
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29
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Mukherjee S, Mukherjee M, Mukherjee A, Bhagi-Damodaran A, Lu Y, Dey A. O 2 Reduction by Biosynthetic Models of Cytochrome c Oxidase: Insights into Role of Proton Transfer Residues from Perturbed Active Sites Models of CcO. ACS Catal 2018; 8:8915-8924. [PMID: 35693844 DOI: 10.1021/acscatal.8b02240] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Myoglobin based biosynthetic models of perturbed cytochrome c oxidase (CcO) active site are reconstituted, in situ, on electrodes where glutamate residues are systematically introduced in the distal site of the heme/Cu active site instead of a tyrosine residue. These biochemical electrodes show efficient 4e-/4H+ reduction with turnover rates and numbers more than 107 M-1 s-1 and 104, respectively. The H2O/D2O isotope effects of these series of crystallographically characterized mutants bearing zero, one, and two glutamate residues near the heme Cu active site of these perturbed CcO mimics are 16, 4, and 2, respectively. In situ SERRS-RDE data indicate complete change in the rate-determining step as proton transfer residues are introduced near the active site. The high selectivity for 4e-/4H+ O2 reduction and systematic variation of KSIE demonstrate the dominant role of proton transfer residues on the isotope effect on rate and rate-determining step of O2 reduction.
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Affiliation(s)
- Sohini Mukherjee
- Department of Inorganic Chemistry, Indian Association for the Cultivation of Science, Kolkata 700032, India
| | - Manjistha Mukherjee
- Department of Inorganic Chemistry, Indian Association for the Cultivation of Science, Kolkata 700032, India
| | - Arnab Mukherjee
- Department of Chemistry, University of Illinois at Urbana—Champaign, Champaign, Illinois 61801, United States
| | - Ambika Bhagi-Damodaran
- Department of Chemistry, University of Illinois at Urbana—Champaign, Champaign, Illinois 61801, United States
| | - Yi Lu
- Department of Chemistry, University of Illinois at Urbana—Champaign, Champaign, Illinois 61801, United States
| | - Abhishek Dey
- Department of Inorganic Chemistry, Indian Association for the Cultivation of Science, Kolkata 700032, India
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30
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Hemschemeier A, Happe T. The plasticity of redox cofactors: from metalloenzymes to redox-active DNA. Nat Rev Chem 2018. [DOI: 10.1038/s41570-018-0029-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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31
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Bhunia S, Rana A, Roy P, Martin DJ, Pegis ML, Roy B, Dey A. Rational Design of Mononuclear Iron Porphyrins for Facile and Selective 4e -/4H + O 2 Reduction: Activation of O-O Bond by 2nd Sphere Hydrogen Bonding. J Am Chem Soc 2018; 140:9444-9457. [PMID: 29975839 DOI: 10.1021/jacs.8b02983] [Citation(s) in RCA: 77] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Facile and selective 4e-/4H+ electrochemical reduction of O2 to H2O in aqueous medium has been a sought-after goal for several decades. Elegant but synthetically demanding cytochrome c oxidase mimics have demonstrated selective 4e-/4H+ electrochemical O2 reduction to H2O is possible with rate constants as fast as 105 M-1 s-1 under heterogeneous conditions in aqueous media. Over the past few years, in situ mechanistic investigations on iron porphyrin complexes adsorbed on electrodes have revealed that the rate and selectivity of this multielectron and multiproton process is governed by the reactivity of a ferric hydroperoxide intermediate. The barrier of O-O bond cleavage determines the overall rate of O2 reduction and the site of protonation determines the selectivity. In this report, a series of mononuclear iron porphyrin complexes are rationally designed to achieve efficient O-O bond activation and site-selective proton transfer to effect facile and selective electrochemical reduction of O2 to water. Indeed, these crystallographically characterized complexes accomplish facile and selective reduction of O2 with rate constants >107 M-1 s-1 while retaining >95% selectivity when adsorbed on electrode surfaces (EPG) in water. These oxygen reduction reaction rate constants are 2 orders of magnitude faster than all known heme/Cu complexes and these complexes retain >90% selectivity even under rate determining electron transfer conditions that generally can only be achieved by installing additional redox active groups in the catalyst.
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Affiliation(s)
- Sarmistha Bhunia
- Department of Inorganic Chemistry , Indian Association for the Cultivation of Science , 2A Raja SC Mullick Road , Kolkata , West Bengal 700032 , India
| | - Atanu Rana
- Department of Inorganic Chemistry , Indian Association for the Cultivation of Science , 2A Raja SC Mullick Road , Kolkata , West Bengal 700032 , India
| | - Pronay Roy
- Department of Inorganic Chemistry , Indian Association for the Cultivation of Science , 2A Raja SC Mullick Road , Kolkata , West Bengal 700032 , India
| | - Daniel J Martin
- Department of Chemistry , Yale University , New Haven , Connecticut 06520 , United States
| | - Michael L Pegis
- Department of Chemistry , Yale University , New Haven , Connecticut 06520 , United States.,Department of Chemistry , Massachusetts Institute of Technology , Cambridge , Massachusetts 02139 , United States
| | - Bijan Roy
- Department of Inorganic Chemistry , Indian Association for the Cultivation of Science , 2A Raja SC Mullick Road , Kolkata , West Bengal 700032 , India
| | - Abhishek Dey
- Department of Inorganic Chemistry , Indian Association for the Cultivation of Science , 2A Raja SC Mullick Road , Kolkata , West Bengal 700032 , India
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32
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In silico design of potentially functional artificial metallo-haloalkane dehalogenase containing catalytic zinc. 3 Biotech 2018; 8:314. [PMID: 30023146 DOI: 10.1007/s13205-018-1333-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Accepted: 07/02/2018] [Indexed: 01/05/2023] Open
Abstract
Artificial metalloenzymes are unique as they combine the good features of homogeneous and enzymatic catalysts, and they can potentially improve some difficult catalytic assays. This study reports a method that can be used to create an artificial metal-binding site prior to proving it to be functional in a wet lab. Haloalkane dehalogenase was grafted into a metal-binding site to form an artificial metallo-haloalkane dehalogenase and was studied for its potential functionalities in silico. Computational protocols regarding dynamic metal docking were studied using native metalloenzymes and functional artificial metalloenzymes. Using YASARA Structure, a simulation box covering template structure was created to be filled with water molecules followed by one mutated water molecule closest to the metal-binding site to metal ion. A simple energy minimization step was subsequently run using an AMBER force field to allow the metal ion to interact with the metal-binding residues. Long molecular dynamic simulation using YASARA Structure was performed to analyze the stability of the metal-binding site and the distance between metal-binding residues. Metal ions fluctuating around 2.0 Å across a 20 ns simulation indicated a stable metal-binding site. Metal-binding energies were predicted using FoldX, with a native metalloenzyme (carbonic anhydrase) scoring 18.0 kcal/mol and the best mutant model (C1a) scoring 16.4 kcal/mol. Analysis of the metal-binding site geometry was performed using CheckMyMetal, and all scores for the metalloenzymes and mutant models were in an acceptable range. Like native metalloenzymes, the metal-binding site of C1a was supported by residues in the second coordination shell to maintain a more coordinated metal-binding site. Short-chain multihalogenated alkanes (1,2-dibromoethane and 1,2,3-trichloropropane) were able to dock in the active site of C1a. The halides of the substrate were in contact with both the metal and halide-stabilizing residues, thus indicating a better stabilization of the substrate. The simple catalytic mechanism proposed is that the metal ion interacted with halogen and polarized the carbon-halogen bond, thus making the alpha carbon susceptible to attack by nucleophilic hydroxide. The interaction between halogen in the metal ion and halide-stabilizing residues may help to improve the stabilization of the substrate-enzyme complex and reduce the activation energy. This study reports a modified dynamic metal-docking protocol and validation tests to verify the metal-binding site. These approaches can be applied to design different kinds of artificial metalloenzymes or metal-binding sites.
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Huang X, Groves JT. Oxygen Activation and Radical Transformations in Heme Proteins and Metalloporphyrins. Chem Rev 2018; 118:2491-2553. [PMID: 29286645 PMCID: PMC5855008 DOI: 10.1021/acs.chemrev.7b00373] [Citation(s) in RCA: 591] [Impact Index Per Article: 98.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Indexed: 12/20/2022]
Abstract
As a result of the adaptation of life to an aerobic environment, nature has evolved a panoply of metalloproteins for oxidative metabolism and protection against reactive oxygen species. Despite the diverse structures and functions of these proteins, they share common mechanistic grounds. An open-shell transition metal like iron or copper is employed to interact with O2 and its derived intermediates such as hydrogen peroxide to afford a variety of metal-oxygen intermediates. These reactive intermediates, including metal-superoxo, -(hydro)peroxo, and high-valent metal-oxo species, are the basis for the various biological functions of O2-utilizing metalloproteins. Collectively, these processes are called oxygen activation. Much of our understanding of the reactivity of these reactive intermediates has come from the study of heme-containing proteins and related metalloporphyrin compounds. These studies not only have deepened our understanding of various functions of heme proteins, such as O2 storage and transport, degradation of reactive oxygen species, redox signaling, and biological oxygenation, etc., but also have driven the development of bioinorganic chemistry and biomimetic catalysis. In this review, we survey the range of O2 activation processes mediated by heme proteins and model compounds with a focus on recent progress in the characterization and reactivity of important iron-oxygen intermediates. Representative reactions initiated by these reactive intermediates as well as some context from prior decades will also be presented. We will discuss the fundamental mechanistic features of these transformations and delineate the underlying structural and electronic factors that contribute to the spectrum of reactivities that has been observed in nature as well as those that have been invented using these paradigms. Given the recent developments in biocatalysis for non-natural chemistries and the renaissance of radical chemistry in organic synthesis, we envision that new enzymatic and synthetic transformations will emerge based on the radical processes mediated by metalloproteins and their synthetic analogs.
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Affiliation(s)
- Xiongyi Huang
- Department
of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
- Department
of Chemistry, California Institute of Technology, Pasadena, California 91125, United States
| | - John T. Groves
- Department
of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
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34
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Design of artificial metalloproteins/metalloenzymes by tuning noncovalent interactions. J Biol Inorg Chem 2017; 23:7-25. [DOI: 10.1007/s00775-017-1506-8] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2017] [Accepted: 09/20/2017] [Indexed: 12/12/2022]
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35
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Fukuzumi S, Lee YM, Nam W. Mechanisms of Two-Electron versus Four-Electron Reduction of Dioxygen Catalyzed by Earth-Abundant Metal Complexes. ChemCatChem 2017. [DOI: 10.1002/cctc.201701064] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
- Shunichi Fukuzumi
- Department of Chemistry and Nano Science; Ewha Womans University; Seoul 03760 Korea
- Faculty of Science and Engineering; Meijo University; SENTAN, Japan, Science and Technology Agency, JST; Nagoya Aichi 468-8502 Japan
| | - Yong-Min Lee
- Department of Chemistry and Nano Science; Ewha Womans University; Seoul 03760 Korea
| | - Wonwoo Nam
- Department of Chemistry and Nano Science; Ewha Womans University; Seoul 03760 Korea
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36
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Reed JH, Shi Y, Zhu Q, Chakraborty S, Mirts EN, Petrik ID, Bhagi-Damodaran A, Ross M, Moënne-Loccoz P, Zhang Y, Lu Y. Manganese and Cobalt in the Nonheme-Metal-Binding Site of a Biosynthetic Model of Heme-Copper Oxidase Superfamily Confer Oxidase Activity through Redox-Inactive Mechanism. J Am Chem Soc 2017; 139:12209-12218. [PMID: 28768416 PMCID: PMC5673108 DOI: 10.1021/jacs.7b05800] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The presence of a nonheme metal, such as copper and iron, in the heme-copper oxidase (HCO) superfamily is critical to the enzymatic activity of reducing O2 to H2O, but the exact mechanism the nonheme metal ion uses to confer and fine-tune the activity remains to be understood. We herein report that manganese and cobalt can bind to the same nonheme site and confer HCO activity in a heme-nonheme biosynthetic model in myoglobin. While the initial rates of O2 reduction by the Mn, Fe, and Co derivatives are similar, the percentages of reactive oxygen species (ROS) formation are 7%, 4%, and 1% and the total turnovers are 5.1 ± 1.1, 13.4 ± 0.7, and 82.5 ± 2.5, respectively. These results correlate with the trends of nonheme-metal-binding dissociation constants (35, 22, and 9 μM) closely, suggesting that tighter metal binding can prevent ROS release from the active site, lessen damage to the protein, and produce higher total turnover numbers. Detailed spectroscopic, electrochemical, and computational studies found no evidence of redox cycling of manganese or cobalt in the enzymatic reactions and suggest that structural and electronic effects related to the presence of different nonheme metals lead to the observed differences in reactivity. This study of the roles of nonheme metal ions beyond the Cu and Fe found in native enzymes has provided deeper insights into nature's choice of metal ion and reaction mechanism and allows for finer control of the enzymatic activity, which is a basis for the design of efficient catalysts for the oxygen reduction reaction in fuel cells.
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Affiliation(s)
- Julian H. Reed
- Department of Biochemistry, University of Illinois at
Urbana-Champaign, Urbana, IL, 61801, USA
| | - Yelu Shi
- Department of Biomedical Engineering, Chemistry, and Biological
Sciences, Stevens Institute of Technology, Hoboken, NJ, 07030, USA
| | - Qianhong Zhu
- Division of Environmental & Biomolecular Systems, Institute
of Environmental Health, Oregon Health & Science University, Portland, OR,
97239, USA
| | - Saumen Chakraborty
- Department of Chemistry & Biochemistry, University of
Mississippi, Oxford, Mississippi, 38677, USA
| | - Evan N. Mirts
- Center for Biophysics and Quantitative Biology, University of
Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Igor D. Petrik
- Department of Chemistry, University of Illinois at Urbana-Champaign,
Urbana, IL, 61801, USA
| | - Ambika Bhagi-Damodaran
- Department of Pharmaceutical Chemistry, University of California,
San Francisco, San Francisco, CA, 94143, USA
| | - Matthew Ross
- Department of Chemistry, Northwestern University, Evanston, IL,
60208, USA
| | - Pierre Moënne-Loccoz
- Division of Environmental & Biomolecular Systems, Institute
of Environmental Health, Oregon Health & Science University, Portland, OR,
97239, USA
| | - Yong Zhang
- Department of Biomedical Engineering, Chemistry, and Biological
Sciences, Stevens Institute of Technology, Hoboken, NJ, 07030, USA
| | - Yi Lu
- Department of Biochemistry, University of Illinois at
Urbana-Champaign, Urbana, IL, 61801, USA
- Center for Biophysics and Quantitative Biology, University of
Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
- Department of Chemistry, University of Illinois at Urbana-Champaign,
Urbana, IL, 61801, USA
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37
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Schwizer F, Okamoto Y, Heinisch T, Gu Y, Pellizzoni MM, Lebrun V, Reuter R, Köhler V, Lewis JC, Ward TR. Artificial Metalloenzymes: Reaction Scope and Optimization Strategies. Chem Rev 2017; 118:142-231. [PMID: 28714313 DOI: 10.1021/acs.chemrev.7b00014] [Citation(s) in RCA: 490] [Impact Index Per Article: 70.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The incorporation of a synthetic, catalytically competent metallocofactor into a protein scaffold to generate an artificial metalloenzyme (ArM) has been explored since the late 1970's. Progress in the ensuing years was limited by the tools available for both organometallic synthesis and protein engineering. Advances in both of these areas, combined with increased appreciation of the potential benefits of combining attractive features of both homogeneous catalysis and enzymatic catalysis, led to a resurgence of interest in ArMs starting in the early 2000's. Perhaps the most intriguing of potential ArM properties is their ability to endow homogeneous catalysts with a genetic memory. Indeed, incorporating a homogeneous catalyst into a genetically encoded scaffold offers the opportunity to improve ArM performance by directed evolution. This capability could, in turn, lead to improvements in ArM efficiency similar to those obtained for natural enzymes, providing systems suitable for practical applications and greater insight into the role of second coordination sphere interactions in organometallic catalysis. Since its renaissance in the early 2000's, different aspects of artificial metalloenzymes have been extensively reviewed and highlighted. Our intent is to provide a comprehensive overview of all work in the field up to December 2016, organized according to reaction class. Because of the wide range of non-natural reactions catalyzed by ArMs, this was done using a functional-group transformation classification. The review begins with a summary of the proteins and the anchoring strategies used to date for the creation of ArMs, followed by a historical perspective. Then follows a summary of the reactions catalyzed by ArMs and a concluding critical outlook. This analysis allows for comparison of similar reactions catalyzed by ArMs constructed using different metallocofactor anchoring strategies, cofactors, protein scaffolds, and mutagenesis strategies. These data will be used to construct a searchable Web site on ArMs that will be updated regularly by the authors.
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Affiliation(s)
- Fabian Schwizer
- Department of Chemistry, Spitalstrasse 51, University of Basel , CH-4056 Basel, Switzerland
| | - Yasunori Okamoto
- Department of Chemistry, Spitalstrasse 51, University of Basel , CH-4056 Basel, Switzerland
| | - Tillmann Heinisch
- Department of Chemistry, Spitalstrasse 51, University of Basel , CH-4056 Basel, Switzerland
| | - Yifan Gu
- Searle Chemistry Laboratory, University of Chicago , 5735 S. Ellis Ave., Chicago, Illinois 60637, United States
| | - Michela M Pellizzoni
- Department of Chemistry, Spitalstrasse 51, University of Basel , CH-4056 Basel, Switzerland
| | - Vincent Lebrun
- Department of Chemistry, Spitalstrasse 51, University of Basel , CH-4056 Basel, Switzerland
| | - Raphael Reuter
- Department of Chemistry, Spitalstrasse 51, University of Basel , CH-4056 Basel, Switzerland
| | - Valentin Köhler
- Department of Chemistry, Spitalstrasse 51, University of Basel , CH-4056 Basel, Switzerland
| | - Jared C Lewis
- Searle Chemistry Laboratory, University of Chicago , 5735 S. Ellis Ave., Chicago, Illinois 60637, United States
| | - Thomas R Ward
- Department of Chemistry, Spitalstrasse 51, University of Basel , CH-4056 Basel, Switzerland
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38
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Bhagi-Damodaran A, Kahle M, Shi Y, Zhang Y, Ädelroth P, Lu Y. Insights Into How Heme Reduction Potentials Modulate Enzymatic Activities of a Myoglobin-based Functional Oxidase. Angew Chem Int Ed Engl 2017; 56:6622-6626. [PMID: 28470988 DOI: 10.1002/anie.201701916] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Indexed: 01/01/2023]
Abstract
Heme-copper oxidase (HCO) is a class of respiratory enzymes that use a heme-copper center to catalyze O2 reduction to H2 O. While heme reduction potential (E°') of different HCO types has been found to vary >500 mV, its impact on HCO activity remains poorly understood. Here, we use a set of myoglobin-based functional HCO models to investigate the mechanism by which heme E°' modulates oxidase activity. Rapid stopped-flow kinetic measurements show that increasing heme E°' by ca. 210 mV results in increases in electron transfer (ET) rates by 30-fold, rate of O2 binding by 12-fold, O2 dissociation by 35-fold, while decreasing O2 affinity by 3-fold. Theoretical calculations reveal that E°' modulation has significant implications on electronic charge of both heme iron and O2 , resulting in increased O2 dissociation and reduced O2 affinity at high E°' values. Overall, this work suggests that fine-tuning E°' in HCOs and other heme enzymes can modulate their substrate affinity, ET rate and enzymatic activity.
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Affiliation(s)
- Ambika Bhagi-Damodaran
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Maximilian Kahle
- Department of Biochemistry and Biophysics, Arrhenius Laboratories for Natural Sciences, Stockholm University, SE-10691, Stockholm, Sweden
| | - Yelu Shi
- Department of Biomedical Engineering, Chemistry and Biological Sciences, Stevens Institute of Technology, Hoboken, New Jersey, NY, 07030, USA
| | - Yong Zhang
- Department of Biomedical Engineering, Chemistry and Biological Sciences, Stevens Institute of Technology, Hoboken, New Jersey, NY, 07030, USA
| | - Pia Ädelroth
- Department of Biochemistry and Biophysics, Arrhenius Laboratories for Natural Sciences, Stockholm University, SE-10691, Stockholm, Sweden
| | - Yi Lu
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
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39
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Bhagi‐Damodaran A, Kahle M, Shi Y, Zhang Y, Ädelroth P, Lu Y. Insights Into How Heme Reduction Potentials Modulate Enzymatic Activities of a Myoglobin‐based Functional Oxidase. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201701916] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
| | - Maximilian Kahle
- Department of Biochemistry and Biophysics Arrhenius Laboratories for Natural Sciences Stockholm University SE-10691 Stockholm Sweden
| | - Yelu Shi
- Department of Biomedical Engineering, Chemistry and Biological Sciences Stevens Institute of Technology Hoboken, New Jersey NY 07030 USA
| | - Yong Zhang
- Department of Biomedical Engineering, Chemistry and Biological Sciences Stevens Institute of Technology Hoboken, New Jersey NY 07030 USA
| | - Pia Ädelroth
- Department of Biochemistry and Biophysics Arrhenius Laboratories for Natural Sciences Stockholm University SE-10691 Stockholm Sweden
| | - Yi Lu
- Department of Chemistry University of Illinois at Urbana-Champaign Urbana IL 61801 USA
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40
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Hu S, He B, Du KJ, Wang XJ, Gao SQ, Lin YW. Peroxidase Activity of a c-Type Cytochrome b5 in the Non-Native State is Comparable to that of Native Peroxidases. ChemistryOpen 2017. [PMID: 28638761 PMCID: PMC5474653 DOI: 10.1002/open.201700055] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The design of artificial metalloenzymes has achieved tremendous progress, although few designs can achieve catalytic performances comparable to that of native enzymes. Moreover, the structure and function of artificial metalloenzymes in non‐native states has rarely been explored. Herein, we found that a c‐type cytochrome b5 (Cyt b5), N57C/S71C Cyt b5, with heme covalently attached to the protein matrix through two Cys–heme linkages, adopts a non‐native state with an open heme site after guanidine hydrochloride (Gdn⋅HCl)‐induced unfolding, which facilitates H2O2 activation and substrate binding. Stopped‐flow kinetic studies further revealed that c‐type Cyt b5 in the non‐native state exhibited impressive peroxidase activity comparable to that of native peroxidases, such as the most efficient horseradish peroxidase. This study presents an alternative approach to the design of functional artificial metalloenzymes by exploring enzymatic functions in non‐native states.
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Affiliation(s)
- Shan Hu
- School of Chemistry and Chemical Engineering University of South China Hengyang 421001 P.R. China
| | - Bo He
- School of Chemistry and Chemical Engineering University of South China Hengyang 421001 P.R. China
| | - Ke-Jie Du
- School of Chemistry and Chemical Engineering University of South China Hengyang 421001 P.R. China
| | - Xiao-Juan Wang
- School of Chemistry and Chemical Engineering University of South China Hengyang 421001 P.R. China
| | - Shu-Qin Gao
- Laboratory of Protein Structure and Function University of South China Hengyang 421001 P.R. China
| | - Ying-Wu Lin
- School of Chemistry and Chemical Engineering University of South China Hengyang 421001 P.R. China.,Laboratory of Protein Structure and Function University of South China Hengyang 421001 P.R. China
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41
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D'Souza A, Wu X, Yeow EKL, Bhattacharjya S. Designed Heme-Cage β-Sheet Miniproteins. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201702472] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Areetha D'Souza
- School of Biological Sciences; Nanyang Technological University; Singapore 637551 Singapore
| | - Xiangyang Wu
- School of Physical and Mathematical Sciences; Nanyang Technological University; Singapore 637371 Singapore
| | - Edwin Kok Lee Yeow
- School of Physical and Mathematical Sciences; Nanyang Technological University; Singapore 637371 Singapore
| | - Surajit Bhattacharjya
- School of Biological Sciences; Nanyang Technological University; Singapore 637551 Singapore
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42
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D'Souza A, Wu X, Yeow EKL, Bhattacharjya S. Designed Heme-Cage β-Sheet Miniproteins. Angew Chem Int Ed Engl 2017; 56:5904-5908. [PMID: 28440962 DOI: 10.1002/anie.201702472] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2017] [Indexed: 01/21/2023]
Abstract
The structure and function of naturally occurring proteins are governed by a large number of amino acids (≥100). The design of miniature proteins with desired structures and functions not only substantiates our knowledge about proteins but can also contribute to the development of novel applications. Excellent progress has been made towards the design of helical proteins with diverse functions. However, the development of functional β-sheet proteins remains challenging. Herein, we describe the construction and characterization of four-stranded β-sheet miniproteins made up of about 19 amino acids that bind heme inside a hydrophobic binding pocket or "heme cage" by bis-histidine coordination in an aqueous environment. The designed miniproteins bound to heme with high affinity comparable to that of native heme proteins. Atomic-resolution structures confirmed the presence of a four-stranded β-sheet fold. The heme-protein complexes also exhibited high stability against thermal and chaotrope-induced unfolding.
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Affiliation(s)
- Areetha D'Souza
- School of Biological Sciences, Nanyang Technological University, Singapore, 637551, Singapore
| | - Xiangyang Wu
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, 637371, Singapore
| | - Edwin Kok Lee Yeow
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, 637371, Singapore
| | - Surajit Bhattacharjya
- School of Biological Sciences, Nanyang Technological University, Singapore, 637551, Singapore
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43
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44
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Quist DA, Diaz DE, Liu JJ, Karlin KD. Activation of dioxygen by copper metalloproteins and insights from model complexes. J Biol Inorg Chem 2017; 22:253-288. [PMID: 27921179 PMCID: PMC5600896 DOI: 10.1007/s00775-016-1415-2] [Citation(s) in RCA: 163] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Accepted: 11/11/2016] [Indexed: 02/08/2023]
Abstract
Nature uses dioxygen as a key oxidant in the transformation of biomolecules. Among the enzymes that are utilized for these reactions are copper-containing metalloenzymes, which are responsible for important biological functions such as the regulation of neurotransmitters, dioxygen transport, and cellular respiration. Enzymatic and model system studies work in tandem in order to gain an understanding of the fundamental reductive activation of dioxygen by copper complexes. This review covers the most recent advancements in the structures, spectroscopy, and reaction mechanisms for dioxygen-activating copper proteins and relevant synthetic models thereof. An emphasis has also been placed on cofactor biogenesis, a fundamentally important process whereby biomolecules are post-translationally modified by the pro-enzyme active site to generate cofactors which are essential for the catalytic enzymatic reaction. Significant questions remaining in copper-ion-mediated O2-activation in copper proteins are addressed.
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Affiliation(s)
- David A Quist
- Department of Chemistry, Johns Hopkins University, Baltimore, MD, 21218, USA
| | - Daniel E Diaz
- Department of Chemistry, Johns Hopkins University, Baltimore, MD, 21218, USA
| | - Jeffrey J Liu
- Department of Chemistry, Johns Hopkins University, Baltimore, MD, 21218, USA
| | - Kenneth D Karlin
- Department of Chemistry, Johns Hopkins University, Baltimore, MD, 21218, USA.
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45
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Bhagi-Damodaran A, Michael MA, Zhu Q, Reed J, Sandoval BA, Mirts EN, Chakraborty S, Moënne-Loccoz P, Zhang Y, Lu Y. Why copper is preferred over iron for oxygen activation and reduction in haem-copper oxidases. Nat Chem 2017; 9:257-263. [PMID: 28221360 PMCID: PMC5321616 DOI: 10.1038/nchem.2643] [Citation(s) in RCA: 95] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2016] [Accepted: 09/09/2016] [Indexed: 01/13/2023]
Abstract
Haem-copper oxidase (HCO) catalyses the natural reduction of oxygen to water using a haem-copper centre. Despite decades of research on HCOs, the role of non-haem metal and the reason for nature's choice of copper over other metals such as iron remains unclear. Here, we use a biosynthetic model of HCO in myoglobin that selectively binds different non-haem metals to demonstrate 30-fold and 11-fold enhancements in the oxidase activity of Cu- and Fe-bound HCO mimics, respectively, as compared with Zn-bound mimics. Detailed electrochemical, kinetic and vibrational spectroscopic studies, in tandem with theoretical density functional theory calculations, demonstrate that the non-haem metal not only donates electrons to oxygen but also activates it for efficient O-O bond cleavage. Furthermore, the higher redox potential of copper and the enhanced weakening of the O-O bond from the higher electron density in the d orbital of copper are central to its higher oxidase activity over iron. This work resolves a long-standing question in bioenergetics, and renders a chemical-biological basis for the design of future oxygen-reduction catalysts.
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Affiliation(s)
| | - Matthew A. Michael
- Department of Biomedical Engineering, Chemistry, and
Biological Sciences, Stevens Institute of Technology, Hoboken, NJ, USA
| | - Qianhong Zhu
- Division of Environmental & Biomolecular Systems, Institute
of Environmental Health, Oregon Health & Science University, 3181 SW Sam Jackson Park
Road, Portland, OR, USA
| | - Julian Reed
- Department of Biochemistry, University of Illinois at
Urbana-Champaign, Urbana, IL, USA
| | - Braddock A. Sandoval
- Department of Chemistry, University of Illinois at
Urbana-Champaign, Urbana, IL, USA
| | - Evan N. Mirts
- Center for Biophysics and Quantitative Biology, University
of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Saumen Chakraborty
- Department of Chemistry, University of Illinois at
Urbana-Champaign, Urbana, IL, USA
| | - Pierre Moënne-Loccoz
- Division of Environmental & Biomolecular Systems, Institute
of Environmental Health, Oregon Health & Science University, 3181 SW Sam Jackson Park
Road, Portland, OR, USA
| | - Yong Zhang
- Department of Biomedical Engineering, Chemistry, and
Biological Sciences, Stevens Institute of Technology, Hoboken, NJ, USA
| | - Yi Lu
- Department of Chemistry, University of Illinois at
Urbana-Champaign, Urbana, IL, USA
- Department of Biochemistry, University of Illinois at
Urbana-Champaign, Urbana, IL, USA
- Center for Biophysics and Quantitative Biology, University
of Illinois at Urbana-Champaign, Urbana, IL, USA
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46
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Hu C, Yu Y, Wang J. Improving artificial metalloenzymes' activity by optimizing electron transfer. Chem Commun (Camb) 2017; 53:4173-4186. [DOI: 10.1039/c6cc09921a] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
This feature article discusses the strategies to optimize electron transfer efficiency, towards enhancing the activity of artificial metalloenzymes.
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Affiliation(s)
- Cheng Hu
- Laboratory of RNA Biology
- Institute of Biophysics
- Chinese Academy of Sciences
- Chaoyang District
- China
| | - Yang Yu
- Tianjin Institute of Industrial Biotechnology
- Chinese Academy of Sciences
- Tianjin 300308
- China
| | - Jiangyun Wang
- Laboratory of RNA Biology
- Institute of Biophysics
- Chinese Academy of Sciences
- Chaoyang District
- China
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47
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Boralugodage NP, Arachchige RJ, Dutta A, Buchko GW, Shaw WJ. Evaluating the role of acidic, basic, and polar amino acids and dipeptides on a molecular electrocatalyst for H2 oxidation. Catal Sci Technol 2017. [DOI: 10.1039/c6cy02579j] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Outer coordination sphere interactions reduce the overpotential for H2 oxidation catalysts (brown ellipse) compared to those that have –COOH groups but don't have stabilizing interactions (blue ellipse).
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Affiliation(s)
| | | | - Arnab Dutta
- Pacific Northwest National Laboratory
- Richland
- 99352 USA
| | | | - Wendy J. Shaw
- Pacific Northwest National Laboratory
- Richland
- 99352 USA
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48
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Biosynthetic approach to modeling and understanding metalloproteins using unnatural amino acids. Sci China Chem 2016. [DOI: 10.1007/s11426-016-0343-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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49
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Bhagi-Damodaran A, Petrik I, Lu Y. Using Biosynthetic Models of Heme-Copper Oxidase and Nitric Oxide Reductase in Myoglobin to Elucidate Structural Features Responsible for Enzymatic Activities. Isr J Chem 2016; 56:773-790. [PMID: 27994254 PMCID: PMC5161413 DOI: 10.1002/ijch.201600033] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
In biology, a heme-Cu center in heme-copper oxidases (HCOs) is used to catalyze the four-electron reduction of oxygen to water, while a heme-nonheme diiron center in nitric oxide reductases (NORs) is employed to catalyze the two-electron reduction of nitric oxide to nitrous oxide. Although much progress has been made in biochemical and biophysical studies of HCOs and NORs, structural features responsible for similarities and differences within the two enzymatic systems remain to be understood. Here, we discuss the progress made in the design and characterization of myoglobin-based enzyme models of HCOs and NORs. In particular, we focus on use of these models to understand the structure-function relations between HCOs and NORs, including the role of nonheme metals, conserved amino acids in the active site, heme types and hydrogen-bonding network in tuning enzymatic activities and total turnovers. Insights gained from these studies are summarized and future directions are proposed.
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Affiliation(s)
| | - Igor Petrik
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL. 61801
| | - Yi Lu
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL. 61801
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50
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Nastri F, Chino M, Maglio O, Bhagi-Damodaran A, Lu Y, Lombardi A. Design and engineering of artificial oxygen-activating metalloenzymes. Chem Soc Rev 2016; 45:5020-54. [PMID: 27341693 PMCID: PMC5021598 DOI: 10.1039/c5cs00923e] [Citation(s) in RCA: 133] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Many efforts are being made in the design and engineering of metalloenzymes with catalytic properties fulfilling the needs of practical applications. Progress in this field has recently been accelerated by advances in computational, molecular and structural biology. This review article focuses on the recent examples of oxygen-activating metalloenzymes, developed through the strategies of de novo design, miniaturization processes and protein redesign. Considerable progress in these diverse design approaches has produced many metal-containing biocatalysts able to adopt the functions of native enzymes or even novel functions beyond those found in Nature.
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Affiliation(s)
- Flavia Nastri
- Department of Chemical Sciences, University of Naples “Federico II”, Via Cintia, 80126 Naples, Italy
| | - Marco Chino
- Department of Chemical Sciences, University of Naples “Federico II”, Via Cintia, 80126 Naples, Italy
| | - Ornella Maglio
- Department of Chemical Sciences, University of Naples “Federico II”, Via Cintia, 80126 Naples, Italy
- IBB, CNR, Via Mezzocannone 16, 80134 Naples, Italy
| | - Ambika Bhagi-Damodaran
- Department of Chemistry, University of Illinois at Urbana-Champaign, A322 CLSL, 600 South Mathews Avenue, Urbana, IL 61801
| | - Yi Lu
- Department of Chemistry, University of Illinois at Urbana-Champaign, A322 CLSL, 600 South Mathews Avenue, Urbana, IL 61801
| | - Angela Lombardi
- Department of Chemical Sciences, University of Naples “Federico II”, Via Cintia, 80126 Naples, Italy
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