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Mahoney BJ, Goring AK, Wang Y, Dasika P, Zhou A, Grossbard E, Cascio D, Loo JA, Clubb RT. Development and atomic structure of a new fluorescence-based sensor to probe heme transfer in bacterial pathogens. J Inorg Biochem 2023; 249:112368. [PMID: 37729854 DOI: 10.1016/j.jinorgbio.2023.112368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2023] [Revised: 08/11/2023] [Accepted: 09/07/2023] [Indexed: 09/22/2023]
Abstract
Heme is the most abundant source of iron in the human body and is actively scavenged by bacterial pathogens during infections. Corynebacterium diphtheriae and other species of actinobacteria scavenge heme using cell wall associated and secreted proteins that contain Conserved Region (CR) domains. Here we report the development of a fluorescent sensor to measure heme transfer from the C-terminal CR domain within the HtaA protein (CR2) to other hemoproteins within the heme-uptake system. The sensor contains the CR2 domain inserted into the β2 to β3 turn of the Enhanced Green Fluorescent Protein (EGFP). A 2.45 Å crystal structure reveals the basis of heme binding to the CR2 domain via iron-tyrosyl coordination and shares conserved structural features with CR domains present in Corynebacterium glutamicum. The structure and small angle X-ray scattering experiments are consistent with the sensor adopting a V-shaped structure that exhibits only small fluctuations in inter-domain positioning. We demonstrate heme transfer from the sensor to the CR domains located within the HtaA or HtaB proteins in the heme-uptake system as measured by a ∼ 60% increase in sensor fluorescence and native mass spectrometry.
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Affiliation(s)
- Brendan J Mahoney
- Department of Chemistry and Biochemistry, University of California, Los Angeles, 611 Charles E. Young Drive East, Los Angeles, CA 90095, USA; UCLA-DOE Institute of Genomics and Proteomics, University of California, Los Angeles, 611 Charles E. Young Drive East, Los Angeles, CA 90095, USA
| | - Andrew K Goring
- Department of Chemistry and Biochemistry, University of California, Los Angeles, 611 Charles E. Young Drive East, Los Angeles, CA 90095, USA
| | - Yueying Wang
- Department of Chemistry and Biochemistry, University of California, Los Angeles, 611 Charles E. Young Drive East, Los Angeles, CA 90095, USA
| | - Poojita Dasika
- Department of Chemistry and Biochemistry, University of California, Los Angeles, 611 Charles E. Young Drive East, Los Angeles, CA 90095, USA
| | - Anqi Zhou
- Department of Chemistry and Biochemistry, University of California, Los Angeles, 611 Charles E. Young Drive East, Los Angeles, CA 90095, USA
| | - Emmitt Grossbard
- Department of Chemistry and Biochemistry, University of California, Los Angeles, 611 Charles E. Young Drive East, Los Angeles, CA 90095, USA
| | - Duilio Cascio
- UCLA-DOE Institute of Genomics and Proteomics, University of California, Los Angeles, 611 Charles E. Young Drive East, Los Angeles, CA 90095, USA
| | - Joseph A Loo
- Department of Chemistry and Biochemistry, University of California, Los Angeles, 611 Charles E. Young Drive East, Los Angeles, CA 90095, USA; UCLA-DOE Institute of Genomics and Proteomics, University of California, Los Angeles, 611 Charles E. Young Drive East, Los Angeles, CA 90095, USA; Molecular Biology Institute, University of California, Los Angeles, 611 Charles E. Young Drive East, Los Angeles, CA 90095, USA
| | - Robert T Clubb
- Department of Chemistry and Biochemistry, University of California, Los Angeles, 611 Charles E. Young Drive East, Los Angeles, CA 90095, USA; UCLA-DOE Institute of Genomics and Proteomics, University of California, Los Angeles, 611 Charles E. Young Drive East, Los Angeles, CA 90095, USA; Molecular Biology Institute, University of California, Los Angeles, 611 Charles E. Young Drive East, Los Angeles, CA 90095, USA.
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2
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Redox potential determination of the Hell’s gate globin I protein facing multiple exogenous ligands. Microchem J 2022. [DOI: 10.1016/j.microc.2022.108027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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3
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Nienhaus K, Sharma V, Nienhaus GU, Podust LM. Homodimerization Counteracts the Detrimental Effect of Nitrogenous Heme Ligands on the Enzymatic Activity of Acanthamoeba castellanii CYP51. Biochemistry 2022; 61:1363-1377. [PMID: 35730528 DOI: 10.1021/acs.biochem.2c00198] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Acanthamoeba castellanii is a free-living amoeba that can cause severe eye and brain infections in humans. At present, there is no uniformly effective treatment for any of these infections. However, sterol 14α-demethylases (CYP51s), heme-containing cytochrome P450 enzymes, are known to be validated drug targets in pathogenic fungi and protozoa. The catalytically active P450 form of CYP51 from A. castellanii (AcCYP51) is stabilized against conversion to the inactive P420 form by dimerization. In contrast, Naegleria fowleri CYP51 (NfCYP51) is monomeric in its active P450 and inactive P420 forms. For these two CYP51 enzymes, we have investigated the interplay between the enzyme activity and oligomerization state using steady-state and time-resolved UV-visible absorption spectroscopy. In both enzymes, the P450 → P420 transition is favored under reducing conditions. The transition is accelerated at higher pH, which excludes a protonated thiol as the proximal ligand in P420. Displacement of the proximal thiolate ligand is also promoted by adding exogenous nitrogenous ligands (N-ligands) such as imidazole, isavuconazole, and clotrimazole that bind at the opposite, distal heme side. In AcCYP51, the P450 → P420 transition is faster in the monomer than in the dimer, indicating that the dimeric assembly is critical for stabilizing thiolate coordination to the heme and thus for sustaining AcCYP51 activity. The spectroscopic experiments were complemented with size-exclusion chromatography and X-ray crystallography studies. Collectively, our results indicate that effective inactivation of the AcCYP51 function by azole drugs is due to synergistic interference with AcCYP51 dimerization and promoting irreversible displacement of the proximal heme-thiolate ligand.
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Affiliation(s)
- Karin Nienhaus
- Institute of Applied Physics, Karlsruhe Institute of Technology (KIT), D-76049 Karlsruhe, Germany
| | - Vandna Sharma
- Skaggs School of Pharmacy and Pharmaceutical Sciences, Center for Discovery and Innovation in Parasitic Diseases, University of California San Diego, La Jolla, California 92093, United States
| | - Gerd Ulrich Nienhaus
- Institute of Applied Physics, Karlsruhe Institute of Technology (KIT), D-76049 Karlsruhe, Germany.,Institute of Nanotechnology, Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany.,Institute of Biological and Chemical Systems, Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany.,Department of Physics, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Larissa M Podust
- Skaggs School of Pharmacy and Pharmaceutical Sciences, Center for Discovery and Innovation in Parasitic Diseases, University of California San Diego, La Jolla, California 92093, United States
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4
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Kroneck PMH. Nature's nitrite-to-ammonia expressway, with no stop at dinitrogen. J Biol Inorg Chem 2021; 27:1-21. [PMID: 34865208 PMCID: PMC8840924 DOI: 10.1007/s00775-021-01921-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Accepted: 11/22/2021] [Indexed: 12/26/2022]
Abstract
Since the characterization of cytochrome c552 as a multiheme nitrite reductase, research on this enzyme has gained major interest. Today, it is known as pentaheme cytochrome c nitrite reductase (NrfA). Part of the NH4+ produced from NO2- is released as NH3 leading to nitrogen loss, similar to denitrification which generates NO, N2O, and N2. NH4+ can also be used for assimilatory purposes, thus NrfA contributes to nitrogen retention. It catalyses the six-electron reduction of NO2- to NH4+, hosting four His/His ligated c-type hemes for electron transfer and one structurally differentiated active site heme. Catalysis occurs at the distal side of a Fe(III) heme c proximally coordinated by lysine of a unique CXXCK motif (Sulfurospirillum deleyianum, Wolinella succinogenes) or, presumably, by the canonical histidine in Campylobacter jejeuni. Replacement of Lys by His in NrfA of W. succinogenes led to a significant loss of enzyme activity. NrfA forms homodimers as shown by high resolution X-ray crystallography, and there exist at least two distinct electron transfer systems to the enzyme. In γ-proteobacteria (Escherichia coli) NrfA is linked to the menaquinol pool in the cytoplasmic membrane through a pentaheme electron carrier (NrfB), in δ- and ε-proteobacteria (S. deleyianum, W. succinogenes), the NrfA dimer interacts with a tetraheme cytochrome c (NrfH). Both form a membrane-associated respiratory complex on the extracellular side of the cytoplasmic membrane to optimize electron transfer efficiency. This minireview traces important steps in understanding the nature of pentaheme cytochrome c nitrite reductases, and discusses their structural and functional features.
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Affiliation(s)
- Peter M H Kroneck
- Department of Biology, University of Konstanz, Universitätsstrasse 10, 78457, Konstanz, Germany.
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5
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Diz V, Bieza SA, Oviedo Rouco S, Estrin DA, Murgida DH, Bari SE. Reactivity of inorganic sulfide species towards a pentacoordinated heme model system. J Inorg Biochem 2021; 220:111459. [PMID: 33894504 DOI: 10.1016/j.jinorgbio.2021.111459] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Revised: 03/30/2021] [Accepted: 04/03/2021] [Indexed: 02/07/2023]
Abstract
The reactivity of inorganic sulfide towards ferric bis(N-acetyl)- microperoxidase 11 in sodium dodecyl sulfate has been explored by means of visible absorption and resonance Raman spectroscopies. The reaction has been previously studied in buffered solutions at neutral pH and in the presence of excess sulfide, revealing the formation of a moderately stable hexacoordinated low spin ferric sulfide complex that yields the ferrous form in the hour's timescale. In the surfactant solution, instead, the ferrous form is rapidly formed. The spectroscopic characterization of the heme structure in the surfactant milieu revealed the stabilization of a major ferric mono-histidyl high spin heme, which may be ascribed to out of plane distortions prompting the detachment of the axially ligated water molecule, thus leading to a differential reactivity. The ferric bis(N-acetyl)- microperoxidase 11 in sodium dodecyl sulfate provides a model for pentacoordinated heme platforms with an imidazole-based ligand.
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Affiliation(s)
- Virginia Diz
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Química Inorgánica, Analítica y Química Física, Buenos Aires, Argentina
| | - Silvina A Bieza
- CONICET-Universidad de Buenos Aires, Instituto de Química Física de los Materiales, Medio Ambiente y Energía (INQUIMAE), Buenos Aires, Argentina
| | - Santiago Oviedo Rouco
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Química Inorgánica, Analítica y Química Física, Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires, Instituto de Química Física de los Materiales, Medio Ambiente y Energía (INQUIMAE), Buenos Aires, Argentina
| | - Darío A Estrin
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Química Inorgánica, Analítica y Química Física, Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires, Instituto de Química Física de los Materiales, Medio Ambiente y Energía (INQUIMAE), Buenos Aires, Argentina
| | - Daniel H Murgida
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Química Inorgánica, Analítica y Química Física, Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires, Instituto de Química Física de los Materiales, Medio Ambiente y Energía (INQUIMAE), Buenos Aires, Argentina
| | - Sara E Bari
- CONICET-Universidad de Buenos Aires, Instituto de Química Física de los Materiales, Medio Ambiente y Energía (INQUIMAE), Buenos Aires, Argentina.
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6
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Abiological catalysis by myoglobin mutant with a genetically incorporated unnatural amino acid. Biochem J 2021; 478:1795-1808. [PMID: 33821889 PMCID: PMC10071548 DOI: 10.1042/bcj20210091] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Revised: 04/01/2021] [Accepted: 04/06/2021] [Indexed: 12/13/2022]
Abstract
To inculcate biocatalytic activity in the oxygen-storage protein myoglobin (Mb), a genetically engineered myoglobin mutant H64DOPA (DOPA = L-3,4-dihydroxyphenylalanine) has been created. Incorporation of unnatural amino acids has already demonstrated their ability to accomplish many non-natural functions in proteins efficiently. Herein, the presence of redox-active DOPA residue in the active site of mutant Mb presumably stabilizes the compound I in the catalytic oxidation process by participating in an additional hydrogen bonding (H-bonding) as compared to the WT Mb. Specifically, a general acid-base catalytic pathway was achieved due to the availability of the hydroxyl moieties of DOPA. The reduction potential values of WT (E° = -260 mV) and mutant Mb (E° = -300 mV), w.r.t. Ag/AgCl reference electrode, in the presence of hydrogen peroxide, indicated an additional H-bonding in the mutant protein, which is responsible for the peroxidase activity of the mutant Mb. We observed that in the presence of 5 mM H2O2, H64DOPA Mb oxidizes thioanisole and benzaldehyde with a 10 and 54 folds higher rate, respectively, as opposed to WT Mb. Based on spectroscopic, kinetic, and electrochemical studies, we deduce that DOPA residue, when present within the distal pocket of mutant Mb, alone serves the role of His/Arg-pair of peroxidases.
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7
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Control of distal lysine coordination in a monomeric hemoglobin: A role for heme peripheral interactions. J Inorg Biochem 2021; 219:111437. [PMID: 33892380 DOI: 10.1016/j.jinorgbio.2021.111437] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Revised: 03/20/2021] [Accepted: 03/20/2021] [Indexed: 12/25/2022]
Abstract
THB1 is a monomeric truncated hemoglobin (TrHb) found in the cytoplasm of the green alga Chlamydomonas reinhardtii. The canonical heme coordination scheme in hemoglobins is a proximal histidine ligand and an open distal site. In THB1, the latter site is occupied by Lys53, which is likely to facilitate Fe(II)/Fe(III) redox cycling but hinders dioxygen binding, two features inherent to the NO dioxygenase activity of the protein. TrHb surveys show that a lysine at a position aligning with Lys53 is an insufficient determinant of coordination, and in this study, we sought to identify factors controlling lysine affinity for the heme iron. We solved the "Lys-off" X-ray structure of THB1, represented by the cyanide adduct of the Fe(III) protein, and hypothesized that interactions that differ between the known "Lys-on" structure and the Lys-off structure participate in the control of Lys53 affinity for the heme iron. We applied an experimental approach (site-directed mutagenesis, heme modification, pH titrations in the Fe(III) and Fe(II) states) and a computational approach (MD simulations in the Fe(II) state) to assess the role of heme propionate-protein interactions, distal helix capping, and the composition of the distal pocket. All THB1 modifications resulted in a weakening of lysine affinity and affected the coupling between Lys53 proton binding and heme redox potential. The results supported the importance of specific heme peripheral interactions for the pH stability of iron coordination and the ability of the protein to undergo redox reactions.
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8
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Paradisi A, Bellei M, Paltrinieri L, Bortolotti CA, Di Rocco G, Ranieri A, Borsari M, Sola M, Battistuzzi G. Binding of S. cerevisiae iso-1 cytochrome c and its surface lysine-to-alanine variants to cardiolipin: charge effects and the role of the lipid to protein ratio. J Biol Inorg Chem 2020; 25:467-487. [DOI: 10.1007/s00775-020-01776-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Accepted: 03/06/2020] [Indexed: 11/30/2022]
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9
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Liu HX, Li L, Yang XZ, Wei CW, Cheng HM, Gao SQ, Wen GB, Lin YW. Enhancement of protein stability by an additional disulfide bond designed in human neuroglobin. RSC Adv 2019; 9:4172-4179. [PMID: 35520156 PMCID: PMC9062612 DOI: 10.1039/c8ra10390a] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Accepted: 01/28/2019] [Indexed: 12/21/2022] Open
Abstract
Human neuroglobin (Ngb) forms an intramolecular disulfide bond between Cys46 and Cys55, with a third Cys120 near the protein surface, which is a promising protein model for heme protein design. In order to protect the free Cys120 and to enhance the protein stability, we herein developed a strategy by designing an additional disulfide bond between Cys120 and Cys15 via A15C mutation. The design was supported by molecular modeling, and the formation of Cys15–Cys120 disulfide bond was confirmed experimentally by ESI-MS analysis. Molecular modeling, UV-Vis and CD spectroscopy showed that the additional disulfide bond caused minimal structural alterations of Ngb. Meanwhile, the disulfide bond of Cys15–Cys120 was found to enhance both Gdn·HCl-induced unfolding stability (increased by ∼0.64 M) and pH-induced unfolding stability (decreased by ∼0.69 pH unit), as compared to those of WT Ngb with a single native disulfide bond of Cys46–Cys55. Moreover, the half denaturation temperature (Tm) of A15C Ngb was determined to be higher than 100 °C. In addition, the disulfide bond of Cys15–Cys120 has slight effects on protein function, such as an increase in the rate of O2 release by ∼1.4-fold. This study not only suggests a crucial role of the artificial disulfide in protein stabilization, but also lays the groundwork for further investigation of the structure and function of Ngb, as well as for the design of other functional heme proteins, based on the scaffold of A15C Ngb with an enhanced stability. A disulfide bond of Cys120 and Cys15 was rationally designed in human neuroglobin (Ngb) by A15C mutation, which caused minimal structural alterations, whereas enhanced both chemical and pH stability, with a thermal stability higher than 100 °C.![]()
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Affiliation(s)
- Hai-Xiao Liu
- School of Chemistry and Chemical Engineering
- University of South China
- Hengyang 421001
- China
| | - Lianzhi Li
- School of Chemistry and Chemical Engineering
- Liaocheng University
- Liaocheng 252059
- China
| | - Xin-Zhi Yang
- Laboratory of Protein Structure and Function
- University of South China
- Hengyang 421001
- China
| | - Chuan-Wan Wei
- School of Chemistry and Chemical Engineering
- University of South China
- Hengyang 421001
- China
| | - Hui-Min Cheng
- 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
| | - Ge-Bo Wen
- Laboratory of Protein Structure and Function
- University of South China
- 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
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10
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Hayashi T, Hilvert D, Green AP. Engineered Metalloenzymes with Non-Canonical Coordination Environments. Chemistry 2018; 24:11821-11830. [PMID: 29786902 DOI: 10.1002/chem.201800975] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Indexed: 11/09/2022]
Abstract
Nature employs a limited number of genetically encoded, metal-coordinating residues to create metalloenzymes with diverse structures and functions. Engineered components of the cellular translation machinery can now be exploited to encode non-canonical ligands with user-defined electronic and structural properties. This ability to install "chemically programmed" ligands into proteins can provide powerful chemical probes of metalloenzyme mechanism and presents excellent opportunities to create metalloprotein catalysts with augmented properties and novel activities. In this Concept article, we provide an overview of several recent studies describing the creation of engineered metalloenzymes with interesting catalytic properties, and reveal how characterization of these systems has advanced our understanding of nature's bioinorganic mechanisms. We also highlight how powerful laboratory evolution protocols can be readily adapted to allow optimization of metalloenzymes with non-canonical ligands. This approach combines beneficial features of small molecule and protein catalysis by allowing the installation of a greater variety of local metal coordination environments into evolvable protein scaffolds, and holds great promise for the future creation of powerful metalloprotein catalysts for a host of synthetically valuable transformations.
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Affiliation(s)
- Takahiro Hayashi
- Laboratory of Organic Chemistry, ETH Zurich, 8093, Zurich, Switzerland
| | - Donald Hilvert
- Laboratory of Organic Chemistry, ETH Zurich, 8093, Zurich, Switzerland
| | - Anthony P Green
- School of Chemistry & Manchester Institute of Biotechnology, The University of Manchester, 131 Princess Street, Manchester, M1 7DN, UK
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11
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Lin YW. Structure and function of heme proteins regulated by diverse post-translational modifications. Arch Biochem Biophys 2018; 641:1-30. [DOI: 10.1016/j.abb.2018.01.009] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Revised: 01/10/2018] [Accepted: 01/13/2018] [Indexed: 01/08/2023]
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12
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Wang X, Wei C, Su JH, He B, Wen GB, Lin YW, Zhang Y. A Chiral Ligand Assembly That Confers One-Electron O 2 Reduction Activity for a Cu 2+ -Selective Metallohydrogel. Angew Chem Int Ed Engl 2018; 57:3504-3508. [PMID: 29392823 DOI: 10.1002/anie.201801290] [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] [Received: 01/30/2018] [Indexed: 11/11/2022]
Abstract
The design of functional metallohydrogels is attractive but challenging. A rational approach is introduced for designing functional metallohydrogels using chiral ligands, a phenylalanine derivative with a pyridyl group (l/d-PF). Intriguingly, the as-prepared metallohydrogel exhibits excellent O2 binding and activating properties. Insights into the O2 binding pathway reveals the presence of a novel [(l+d)-PF-Cu3+ -O2- ] species, which can efficiently reduce ferric cytochrome c with the reactive O2- by receiving an electron from reductant ascorbic acid. This study provides helpful instructions for developing new artificial systems with specific functions through the effective combination of chiral ligands with metal ions.
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Affiliation(s)
- Xiaojuan Wang
- School of Chemistry and Chemical Engineering, University of South China, Hengyang, 421001, China
| | - Chuanwan Wei
- School of Chemistry and Chemical Engineering, University of South China, Hengyang, 421001, China
| | - Ji-Hu Su
- CAS Key Laboratory of Microscale Magnetic Resonance, Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui, 230026, China
| | - Bo He
- School of Chemistry and Chemical Engineering, University of South China, Hengyang, 421001, China
| | - Ge-Bo Wen
- Laboratory of Protein Structure and Function, University of South China, 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, Hengyang, 421001, China
| | - Yi Zhang
- Hunan Provincial Key Laboratory of Chemical Power Sources, College of Chemistry and Chemical Engineering, Central South University, Changsha, 410083, China
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13
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Wang X, Wei C, Su JH, He B, Wen GB, Lin YW, Zhang Y. A Chiral Ligand Assembly That Confers One-Electron O2
Reduction Activity for a Cu2+
-Selective Metallohydrogel. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201801290] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Xiaojuan Wang
- School of Chemistry and Chemical Engineering; University of South China; Hengyang 421001 China
| | - Chuanwan Wei
- School of Chemistry and Chemical Engineering; University of South China; Hengyang 421001 China
| | - Ji-Hu Su
- CAS Key Laboratory of Microscale Magnetic Resonance; Department of Modern Physics; University of Science and Technology of China; Hefei Anhui 230026 China
| | - Bo He
- School of Chemistry and Chemical Engineering; University of South China; Hengyang 421001 China
| | - Ge-Bo Wen
- Laboratory of Protein Structure and Function; University of South China; 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; Hengyang 421001 China
| | - Yi Zhang
- Hunan Provincial Key Laboratory of Chemical Power Sources; College of Chemistry and Chemical Engineering; Central South University; Changsha 410083 China
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14
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Cheng HM, Yuan H, Wang XJ, Xu JK, Gao SQ, Wen GB, Tan X, Lin YW. Formation of Cys-heme cross-link in K42C myoglobin under reductive conditions with molecular oxygen. J Inorg Biochem 2018; 182:141-149. [PMID: 29477977 DOI: 10.1016/j.jinorgbio.2018.02.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2018] [Revised: 02/04/2018] [Accepted: 02/13/2018] [Indexed: 12/13/2022]
Abstract
The structure and function of heme proteins are regulated by diverse post-translational modifications including heme-protein cross-links, with the underlying mechanisms not well understood. In this study, we introduced a Cys (K42C) close to the heme 4-vinyl group in sperm whale myoglobin (Mb) and solved its X-ray crystal structure. Interestingly, we found that K42C Mb can partially form a Cys-heme cross-link (termed K42C Mb-X) under dithiothreitol-induced reductive conditions in presence of O2, as suggested by guanidine hydrochloride-induced unfolding and heme extraction studies. Mass spectrometry (MS) studies, together with trypsin digestion studies, further indicated that a thioether bond is formed between Cys42 and the heme 4-vinyl group with an additional mass of 16 Da, likely due to hydroxylation of the α‑carbon. We then proposed a plausible mechanism for the formation of the novel Cys-heme cross-link based on MS, kinetic UV-vis and electron paramagnetic resonance (EPR) studies. Moreover, the Cys-heme cross-link was shown to fine-tune the protein reactivity toward activation of H2O2. This study provides valuable insights into the post-translational modification of heme proteins, and also suggests that the Cys-heme cross-link can be induced to form in vitro, making it useful for design of new heme proteins with a non-dissociable heme and improved functions.
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Affiliation(s)
- Hui-Min Cheng
- School of Chemistry and Chemical Engineering, University of South China, Hengyang 421001, China
| | - Hong Yuan
- Department of Chemistry, Shanghai Key Lab of Chemical Biology for Protein Research & Institute of Biomedical Science, Fudan University, Shanghai 200433, China
| | - Xiao-Juan Wang
- School of Chemistry and Chemical Engineering, University of South China, Hengyang 421001, China
| | - Jia-Kun Xu
- Yellow Sea Fisheries Research Institute, Qingdao 266071, China
| | - Shu-Qin Gao
- Lab of Protein Structure and Function, University of South China, Hengyang 421001, China
| | - Ge-Bo Wen
- Lab of Protein Structure and Function, University of South China, Hengyang 421001, China
| | - Xiangshi Tan
- Department of Chemistry, Shanghai Key Lab of Chemical Biology for Protein Research & Institute of Biomedical Science, Fudan University, Shanghai 200433, China
| | - Ying-Wu Lin
- School of Chemistry and Chemical Engineering, University of South China, Hengyang 421001, China; Lab of Protein Structure and Function, University of South China, Hengyang 421001, China.
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15
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Mashima T, Oohora K, Hayashi T. Substitution of an amino acid residue axially coordinating to the heme molecule in hexameric tyrosine-coordinated hemoprotein to enhance peroxidase activity. J PORPHYR PHTHALOCYA 2018. [DOI: 10.1142/s1088424617500936] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
To convert an originally tyrosine-coordinated heme to histidine-coordinated heme in hexameric tyrosine-coordinated hemoprotein, HTHP, Tyr45, a residue coordinating to the heme cofactor, and Arg25 located in the distal site are replaced with Phe45 and His25, respectively in each of the subunits of the protein. The obtained HTHP mutant (HTHP[Formula: see text] was characterized by SDS-PAGE, ESI-TOF MS, dynamic light scattering measurements and size exclusion chromatography. These analyses indicate that HTHP[Formula: see text] maintains its stable hexameric structure with the altered ligation of each of the heme cofactors. Comparison of UV-vis absorption spectra of the ferric-, ferrous-, CO- and CN-forms of HTHP[Formula: see text] with those of several well-known His-ligated hemoproteins indicates that heme is coordinated by the His25 residue. The reaction of HTHP[Formula: see text] with cumene hydroperoxide produces both cumyl alcohol and acetophenone in a 2.3:1 ratio, indicating that heterolytic O–O bond cleavage dominantly occurs to form the two-electron oxidized species known as compound I. Peroxidase activity of HTHP[Formula: see text] is found to follow Michaelis–Menten kinetics. The [Formula: see text] values of HTHP[Formula: see text] for H[Formula: see text]O[Formula: see text]-dependent oxidation of ABTS and guaiacol are 10- and 100-fold higher, respectively, than those of wild type HTHP (HTHP[Formula: see text]. The [Formula: see text]/[Formula: see text] values of HTHP[Formula: see text] for both substrates are increased 30-fold relative to that of HTHP[Formula: see text]. Moreover, HTHP[Formula: see text] is capable of promoting catalytic sulfoxidation of thioanisole with H[Formula: see text]O[Formula: see text] with a turnover number ca. 2-fold higher than that of HTHP[Formula: see text]. The present findings demonstrate that proximal His ligation to the heme is significantly effective to increase the peroxidase activity in the HTHP matrix.
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Affiliation(s)
- Tsuyoshi Mashima
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Suita 565-0871, Japan
| | - Koji Oohora
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Suita 565-0871, Japan
- Frontier Research Base for Global Young Researchers, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, 565-0871, Japan
- PRESTO, Japan Science and Technology Agency, 4-1-8 Honcho, Kawaguchi 332-0012, Japan
| | - Takashi Hayashi
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Suita 565-0871, Japan
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16
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Bellei M, Bortolotti CA, Di Rocco G, Borsari M, Lancellotti L, Ranieri A, Sola M, Battistuzzi G. The influence of the Cys46/Cys55 disulfide bond on the redox and spectroscopic properties of human neuroglobin. J Inorg Biochem 2018; 178:70-86. [DOI: 10.1016/j.jinorgbio.2017.10.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Revised: 09/21/2017] [Accepted: 10/09/2017] [Indexed: 12/21/2022]
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17
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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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18
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Rapson TD, Liu JW, Sriskantha A, Musameh M, Dunn CJ, Church JS, Woodhead A, Warden AC, Riley MJ, Harmer JR, Noble CJ, Sutherland TD. Design of silk proteins with increased heme binding capacity and fabrication of silk-heme materials. J Inorg Biochem 2017; 177:219-227. [DOI: 10.1016/j.jinorgbio.2017.08.031] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Revised: 08/14/2017] [Accepted: 08/30/2017] [Indexed: 01/12/2023]
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19
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Lamba V, Yabukarski F, Herschlag D. An Activator-Blocker Pair Provides a Controllable On-Off Switch for a Ketosteroid Isomerase Active Site Mutant. J Am Chem Soc 2017; 139:11089-11095. [PMID: 28719738 DOI: 10.1021/jacs.7b03547] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Control of enzyme activity is fundamental to biology and represents a long-term goal in bioengineering and precision therapeutics. While several powerful molecular strategies have been developed, limitations remain in their generalizability and dynamic range. We demonstrate a control mechanism via separate small molecules that turn on the enzyme (activator) and turn off the activation (blocker). We show that a pocket created near the active site base of the enzyme ketosteriod isomerase (KSI) allows efficient and saturable base rescue when the enzyme's natural general base is removed. Binding a small molecule with similar properties but lacking general-base capability in this pocket shuts off rescue. The ability of small molecules to directly participate in and directly block catalysis may afford a broad controllable dynamic range. This approach may be amenable to numerous enzymes and to engineering and screening approaches to identify activators and blockers with strong, specific binding for engineering and therapeutic applications.
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Affiliation(s)
- Vandana Lamba
- Department of Biochemistry, ‡Department of Chemistry, §Department of Chemical Engineering, and ∥Stanford ChEM-H, Stanford University , Stanford, California 94305, United States
| | - Filip Yabukarski
- Department of Biochemistry, ‡Department of Chemistry, §Department of Chemical Engineering, and ∥Stanford ChEM-H, Stanford University , Stanford, California 94305, United States
| | - Daniel Herschlag
- Department of Biochemistry, ‡Department of Chemistry, §Department of Chemical Engineering, and ∥Stanford ChEM-H, Stanford University , Stanford, California 94305, United States
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20
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21
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Hu S, He B, Wang XJ, Gao SQ, Wen GB, Lin YW. Stabilization of cytochrome b 5 by a conserved tyrosine in the secondary sphere of heme active site: A spectroscopic and computational study. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2017; 174:118-123. [PMID: 27888781 DOI: 10.1016/j.saa.2016.11.032] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2016] [Revised: 11/14/2016] [Accepted: 11/16/2016] [Indexed: 06/06/2023]
Abstract
Heme proteins perform a large array of biological functions, with the heme group bound non-covalently or covalently. To probe the stabilization role of conserved tyrosine residue in the secondary sphere of heme site in heme proteins, we herein used cytochrome b5 (Cyt b5) as a model protein, and mutated Tyr30 to Phe or His by removal of Tyr30 associated H-bond network and hydrophobic interaction. We performed thermal-induced unfolding studies for the two mutants, Y30F Cyt b5 and Y30H Cyt b5, as monitored by both UV-Vis and CD spectroscopy, as well as heme transfer studies from these proteins to apo-myoglobin, with wild-type Cyt b5 under the same conditions for comparison. The reduced stability of both mutants indicates that both the H-bonding and hydrophobic interactions associated with Tyr30 contribute to the protein stability. Moreover, we performed molecular modeling studies, which revealed that the hydrophobic interaction in the local region of Y30F Cyt b5 was well-remained, whereas Y30H Cyt b5 formed an H-bond network. These observations suggest that the conserved Tyr30 in Cyt b5 is not replaceable due to the presence of both the H-bond network and hydrophobic interaction in the secondary sphere of the heme active site. As demonstrated here for Cyt b5, it may be of practical importance for design of artificial heme proteins by engineering a Tyr in the secondary sphere with improved properties and functions.
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Affiliation(s)
- Shan Hu
- School of Chemistry and Chemical Engineering, University of South China, Hengyang 421001, China
| | - Bo He
- School of Chemistry and Chemical Engineering, University of South China, Hengyang 421001, China
| | - Xiao-Juan Wang
- 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
| | - Ge-Bo Wen
- Laboratory of Protein Structure and Function, University of South China, 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, Hengyang 421001, China.
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22
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Uluisik RC, Akbas N, Lukat-Rodgers GS, Adrian SA, Allen CE, Schmitt MP, Rodgers KR, Dixon DW. Characterization of the second conserved domain in the heme uptake protein HtaA from Corynebacterium diphtheriae. J Inorg Biochem 2017; 167:124-133. [PMID: 27974280 PMCID: PMC5199035 DOI: 10.1016/j.jinorgbio.2016.11.027] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Revised: 10/19/2016] [Accepted: 11/22/2016] [Indexed: 11/20/2022]
Abstract
HtaA is a heme-binding protein that is part of the heme uptake system in Corynebacterium diphtheriae. HtaA contains two conserved regions (CR1 and CR2). It has been previously reported that both domains can bind heme; the CR2 domain binds hemoglobin more strongly than the CR1 domain. In this study, we report the biophysical characteristics of HtaA-CR2. UV-visible spectroscopy and resonance Raman experiments are consistent with this domain containing a single heme that is bound to the protein through an axial tyrosine ligand. Mutants of conserved tyrosine and histidine residues (Y361, H412, and Y490) have been studied. These mutants are isolated with very little heme (≤5%) in comparison to the wild-type protein (~20%). Reconstitution after removal of the heme with butanone gave an alternative form of the protein. The HtaA-CR2 fold is very stable; it was necessary to perform thermal denaturation experiments in the presence of guanidinium hydrochloride. HtaA-CR2 unfolds extremely slowly; even in 6.8M GdnHCl at 37°C, the half-life was 5h. In contrast, the apo forms of WT HtaA-CR2 and the aforementioned mutants unfolded at much lower concentrations of GdnHCl, indicating the role of heme in stabilizing the structure and implying that heme transfer is effected only to a partner protein in vivo.
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Affiliation(s)
- Rizvan C Uluisik
- Department of Chemistry, Georgia State University, Atlanta, GA 30302-3965, United States
| | - Neval Akbas
- Department of Chemistry, Georgia State University, Atlanta, GA 30302-3965, United States
| | - Gudrun S Lukat-Rodgers
- Department of Chemistry and Biochemistry, North Dakota State University, Fargo, ND 58108-6050, United States
| | - Seth A Adrian
- Department of Chemistry and Biochemistry, North Dakota State University, Fargo, ND 58108-6050, United States
| | - Courtni E Allen
- Laboratory of Respiratory and Special Pathogens, Division of Bacterial, Parasitic, and Allergenic Products, Center for Biologics Evaluation, and Research, Food and Drug Administration, Silver Spring, MD 20993, United States
| | - Michael P Schmitt
- Laboratory of Respiratory and Special Pathogens, Division of Bacterial, Parasitic, and Allergenic Products, Center for Biologics Evaluation, and Research, Food and Drug Administration, Silver Spring, MD 20993, United States
| | - Kenton R Rodgers
- Department of Chemistry and Biochemistry, North Dakota State University, Fargo, ND 58108-6050, United States.
| | - Dabney W Dixon
- Department of Chemistry, Georgia State University, Atlanta, GA 30302-3965, United States.
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23
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Wu LB, Du KJ, Nie CM, Gao SQ, Wen GB, Tan X, Lin YW. Peroxidase activity enhancement of myoglobin by two cooperative distal histidines and a channel to the heme pocket. ACTA ACUST UNITED AC 2016. [DOI: 10.1016/j.molcatb.2016.08.018] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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24
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Kurth JM, Brito JA, Reuter J, Flegler A, Koch T, Franke T, Klein EM, Rowe SF, Butt JN, Denkmann K, Pereira IAC, Archer M, Dahl C. Electron Accepting Units of the Diheme Cytochrome c TsdA, a Bifunctional Thiosulfate Dehydrogenase/Tetrathionate Reductase. J Biol Chem 2016; 291:24804-24818. [PMID: 27694441 DOI: 10.1074/jbc.m116.753863] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Revised: 09/22/2016] [Indexed: 11/06/2022] Open
Abstract
The enzymes of the thiosulfate dehydrogenase (TsdA) family are wide-spread diheme c-type cytochromes. Here, redox carriers were studied mediating the flow of electrons arising from thiosulfate oxidation into respiratory or photosynthetic electron chains. In a number of organisms, including Thiomonas intermedia and Sideroxydans lithotrophicus, the tsdA gene is immediately preceded by tsdB encoding for another diheme cytochrome. Spectrophotometric experiments in combination with enzymatic assays in solution showed that TsdB acts as an effective electron acceptor of TsdA in vitro when TsdA and TsdB originate from the same source organism. Although TsdA covers a range from -300 to +150 mV, TsdB is redox active between -100 and +300 mV, thus enabling electron transfer between these hemoproteins. The three-dimensional structure of the TsdB-TsdA fusion protein from the purple sulfur bacterium Marichromatium purpuratum was solved by X-ray crystallography to 2.75 Å resolution providing insights into internal electron transfer. In the oxidized state, this tetraheme cytochrome c contains three hemes with axial His/Met ligation, whereas heme 3 exhibits the His/Cys coordination typical for TsdA active sites. Interestingly, thiosulfate is covalently bound to Cys330 on heme 3. In several bacteria, including Allochromatium vinosum, TsdB is not present, precluding a general and essential role for electron flow. Both AvTsdA and the MpTsdBA fusion react efficiently in vitro with high potential iron-sulfur protein from A. vinosum (Em +350 mV). High potential iron-sulfur protein not only acts as direct electron donor to the reaction center in anoxygenic phototrophs but can also be involved in aerobic respiratory chains.
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Affiliation(s)
- Julia M Kurth
- From the Institut für Mikrobiologie & Biotechnologie, Rheinische Friedrich-Wilhelms-Universität Bonn, 53115 Bonn, Germany
| | - José A Brito
- the Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa (ITQB-UNL), 2780-157 Oeiras, Portugal, and
| | - Jula Reuter
- From the Institut für Mikrobiologie & Biotechnologie, Rheinische Friedrich-Wilhelms-Universität Bonn, 53115 Bonn, Germany
| | - Alexander Flegler
- From the Institut für Mikrobiologie & Biotechnologie, Rheinische Friedrich-Wilhelms-Universität Bonn, 53115 Bonn, Germany
| | - Tobias Koch
- From the Institut für Mikrobiologie & Biotechnologie, Rheinische Friedrich-Wilhelms-Universität Bonn, 53115 Bonn, Germany
| | - Thomas Franke
- From the Institut für Mikrobiologie & Biotechnologie, Rheinische Friedrich-Wilhelms-Universität Bonn, 53115 Bonn, Germany
| | - Eva-Maria Klein
- From the Institut für Mikrobiologie & Biotechnologie, Rheinische Friedrich-Wilhelms-Universität Bonn, 53115 Bonn, Germany
| | - Sam F Rowe
- the Centre for Molecular and Structural Biochemistry, School of Chemistry and School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, United Kingdom
| | - Julea N Butt
- the Centre for Molecular and Structural Biochemistry, School of Chemistry and School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, United Kingdom
| | - Kevin Denkmann
- From the Institut für Mikrobiologie & Biotechnologie, Rheinische Friedrich-Wilhelms-Universität Bonn, 53115 Bonn, Germany
| | - Inês A C Pereira
- the Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa (ITQB-UNL), 2780-157 Oeiras, Portugal, and
| | - Margarida Archer
- the Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa (ITQB-UNL), 2780-157 Oeiras, Portugal, and
| | - Christiane Dahl
- From the Institut für Mikrobiologie & Biotechnologie, Rheinische Friedrich-Wilhelms-Universität Bonn, 53115 Bonn, Germany,
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25
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Girvan HM, Bradley JM, Cheesman MR, Kincaid JR, Liu Y, Czarnecki K, Fisher K, Leys D, Rigby SEJ, Munro AW. Analysis of Heme Iron Coordination in DGCR8: The Heme-Binding Component of the Microprocessor Complex. Biochemistry 2016; 55:5073-83. [DOI: 10.1021/acs.biochem.6b00204] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Hazel M. Girvan
- Centre
for Synthetic Biology of Fine and Specialty Chemicals (SYNBIOCHEM),
Manchester Institute of Biotechnology, Faculty of Life Sciences, University of Manchester, 131 Princess Street, Manchester M1 7DN, U.K
| | - Justin M. Bradley
- School
of Chemistry, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, U.K
| | - Myles R. Cheesman
- School
of Chemistry, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, U.K
| | - James R. Kincaid
- Department
of Chemistry, Marquette University, 535 North 14th Street, Milwaukee, Wisconsin 53233, United States
| | - Yilin Liu
- Department
of Chemistry, Marquette University, 535 North 14th Street, Milwaukee, Wisconsin 53233, United States
| | - Kazimierz Czarnecki
- Department
of Chemistry, Marquette University, 535 North 14th Street, Milwaukee, Wisconsin 53233, United States
| | - Karl Fisher
- Centre
for Synthetic Biology of Fine and Specialty Chemicals (SYNBIOCHEM),
Manchester Institute of Biotechnology, Faculty of Life Sciences, University of Manchester, 131 Princess Street, Manchester M1 7DN, U.K
| | - David Leys
- Centre
for Synthetic Biology of Fine and Specialty Chemicals (SYNBIOCHEM),
Manchester Institute of Biotechnology, Faculty of Life Sciences, University of Manchester, 131 Princess Street, Manchester M1 7DN, U.K
| | - Stephen E. J. Rigby
- Centre
for Synthetic Biology of Fine and Specialty Chemicals (SYNBIOCHEM),
Manchester Institute of Biotechnology, Faculty of Life Sciences, University of Manchester, 131 Princess Street, Manchester M1 7DN, U.K
| | - Andrew W. Munro
- Centre
for Synthetic Biology of Fine and Specialty Chemicals (SYNBIOCHEM),
Manchester Institute of Biotechnology, Faculty of Life Sciences, University of Manchester, 131 Princess Street, Manchester M1 7DN, U.K
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26
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Wu LB, Yuan H, Zhou H, Gao SQ, Nie CM, Tan X, Wen GB, Lin YW. An intramolecular disulfide bond designed in myoglobin fine-tunes both protein structure and peroxidase activity. Arch Biochem Biophys 2016; 600:47-55. [DOI: 10.1016/j.abb.2016.04.012] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Revised: 04/12/2016] [Accepted: 04/23/2016] [Indexed: 01/08/2023]
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27
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Shu X, Su J, Du K, You Y, Gao S, Wen G, Tan X, Lin Y. Rational Design of Dual Active Sites in a Single Protein Scaffold: A Case Study of Heme Protein in Myoglobin. ChemistryOpen 2016; 5:192-196. [PMID: 27933225 PMCID: PMC5125789 DOI: 10.1002/open.201500224] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2015] [Indexed: 01/03/2023] Open
Abstract
Rational protein design has been proven to be a powerful tool for creating functional artificial proteins. Although many artificial metalloproteins with a single active site have been successfully created, those with dual active sites in a single protein scaffold are still relatively rare. In this study, we rationally designed dual active sites in a single heme protein scaffold, myoglobin (Mb), by retaining the native heme site and creating a copper-binding site remotely through a single mutation of Arg118 to His or Met. Isothermal titration calorimetry (ITC) and electron paramagnetic resonance (EPR) studies confirmed that a copper-binding site of [3-His] or [2-His-1-Met] motif was successfully created in the single mutant of R118H Mb and R118M Mb, respectively. UV/Vis kinetic spectroscopy and EPR studies further revealed that both the heme site and the designed copper site exhibited nitrite reductase activity. This study presents a new example for rational protein design with multiple active sites in a single protein scaffold, which also lays the groundwork for further investigation of the structure and function relationship of heme/non-heme proteins.
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Affiliation(s)
- Xiao‐Gang Shu
- School of Chemistry and Chemical EngineeringUniversity of South ChinaHengyang421001P. R. China
| | - Ji‐Hu Su
- Department of Modern PhysicsUniversity of Science and Technology of ChinaHefei230026P. R. China
| | - Ke‐Jie Du
- School of Chemistry and Chemical EngineeringUniversity of South ChinaHengyang421001P. R. China
| | - Yong You
- Laboratory of Protein Structure and FunctionUniversity of South ChinaHengyang421001P. R. China
| | - Shu‐Qin Gao
- Laboratory of Protein Structure and FunctionUniversity of South ChinaHengyang421001P. R. China
| | - Ge‐Bo Wen
- Laboratory of Protein Structure and FunctionUniversity of South ChinaHengyang421001P. R. China
| | - Xiangshi Tan
- Department of ChemistryShanghai Key Lab of Chemical Biology for Protein Research& Institute of Biomedical ScienceFudan UniversityShanghai200433P. R. China
| | - Ying‐Wu Lin
- School of Chemistry and Chemical EngineeringUniversity of South ChinaHengyang421001P. R. China
- Laboratory of Protein Structure and FunctionUniversity of South ChinaHengyang421001P. R. China
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28
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Yan DJ, Yuan H, Li W, Xiang Y, He B, Nie CM, Wen GB, Lin YW, Tan X. How a novel tyrosine-heme cross-link fine-tunes the structure and functions of heme proteins: a direct comparitive study of L29H/F43Y myoglobin. Dalton Trans 2016; 44:18815-22. [PMID: 26458300 DOI: 10.1039/c5dt03040d] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
A heme-protein cross-link is a key post-translational modification (PTM) of heme proteins. Meanwhile, the structural and functional consequences of heme-protein cross-links are not fully understood, due to limited studies on a direct comparison of the same protein with and without the cross-link. A Tyr-heme cross-link with a C-O bond is a newly discovered PTM of heme proteins, and is spontaneously formed in F43Y myoglobin (Mb) between the Tyr hydroxyl group and the heme 4-vinyl group in vivo. In this study, we found that with an additional distal His29 introduced in the heme pocket, the double mutant L29H/F43Y Mb can form two distinct forms under different protein purification conditions, with and without a novel Tyr-heme cross-link. By solving the X-ray structures of both forms of L29H/F43Y Mb and performing spectroscopic studies, we made a direct structural and functional comparison in the same protein scaffold. It revealed that the Tyr-heme cross-link regulates the heme distal hydrogen-bonding network, and fine-tunes not only the spectroscopic and ligand binding properties, but also the protein reactivity. Moreover, the formation of the Tyr-heme cross-link in the double mutant L29H/F43Y Mb was investigated in vitro. This study addressed the key issue of how Tyr-heme cross-link fine-tunes the structure and functions of the heme protein, and provided a plausible mechanism for the formation of the newly discovered Tyr-heme cross-link.
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Affiliation(s)
- Dao-Jing Yan
- School of Chemistry and Chemical Engineering, University of South China, Hengyang 421001, China.
| | - Hong Yuan
- Department of Chemistry/Shanghai Key Lab of Chemical Biology for Protein Research & Institute of Biomedical Science, Fudan University, Shanghai 200433, China.
| | - Wei Li
- Department of Chemistry/Shanghai Key Lab of Chemical Biology for Protein Research & Institute of Biomedical Science, Fudan University, Shanghai 200433, China.
| | - Yu Xiang
- Department of Chemistry, Tsinghua University, Beijing 100084, China
| | - Bo He
- School of Chemistry and Chemical Engineering, University of South China, Hengyang 421001, China.
| | - Chang-Ming Nie
- School of Chemistry and Chemical Engineering, University of South China, Hengyang 421001, China.
| | - Ge-Bo Wen
- Laboratory of Protein Structure and Function, University of South China, Hengyang 421001, 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
| | - Xiangshi Tan
- Department of Chemistry/Shanghai Key Lab of Chemical Biology for Protein Research & Institute of Biomedical Science, Fudan University, Shanghai 200433, China.
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29
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Wu LB, Yuan H, Gao SQ, You Y, Nie CM, Wen GB, Lin YW, Tan X. Regulating the nitrite reductase activity of myoglobin by redesigning the heme active center. Nitric Oxide 2016; 57:21-29. [PMID: 27108710 DOI: 10.1016/j.niox.2016.04.007] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Revised: 04/13/2016] [Accepted: 04/20/2016] [Indexed: 10/21/2022]
Abstract
Heme proteins perform diverse functions in living systems, of which nitrite reductase (NIR) activity receives much attention recently. In this study, to better understand the structural elements responsible for the NIR activity, we used myoglobin (Mb) as a model heme protein and redesigned the heme active center, by introducing one or two distal histidines, and by creating a channel to the heme center with removal of the native distal His64 gate (His to Ala mutation). UV-Vis kinetic studies, combined with EPR studies, showed that a single distal histidine with a suitable position to the heme iron, i.e., His43, is crucial for nitrite (NO2(-)) to nitric oxide (NO) reduction. Moreover, creation of a water channel to the heme center significantly enhanced the NIR activity compared to the corresponding mutant without the channel. In addition, X-ray crystallographic studies of F43H/H64A Mb and its complexes with NO2(-) or NO revealed a unique hydrogen-bonding network in the heme active center, as well as unique substrate and product binding models, providing valuable structural information for the enhanced NIR activity. These findings enriched our understanding of the structure and NIR activity relationship of heme proteins. The approach of creating a channel in this study is also useful for rational design of other functional heme proteins.
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Affiliation(s)
- Lei-Bin Wu
- School of Chemistry and Chemical Engineering, University of South China, Hengyang 421001, China
| | - Hong Yuan
- Department of Chemistry & Institute of Biomedical Science, Fudan University, Shanghai 200433, China
| | - Shu-Qin Gao
- Laboratory of Protein Structure and Function, University of South China, Hengyang 421001, China
| | - Yong You
- Laboratory of Protein Structure and Function, University of South China, Hengyang 421001, China
| | - Chang-Ming Nie
- School of Chemistry and Chemical Engineering, University of South China, Hengyang 421001, China
| | - Ge-Bo Wen
- Laboratory of Protein Structure and Function, University of South China, 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, Hengyang 421001, China.
| | - Xiangshi Tan
- Department of Chemistry & Institute of Biomedical Science, Fudan University, Shanghai 200433, China.
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30
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Huang G, Wang WL, Ning XX, Liu Y, Zhao SK, Guo YA, Wei SJ, Zhou H. Interesting Green Catalysis of Cyclohexane Oxidation over Metal Tetrakis(4-carboxyphenyl)porphyrins Promoted by Zinc Sulfide. Ind Eng Chem Res 2016. [DOI: 10.1021/acs.iecr.6b00061] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Guan Huang
- College of Chemistry and Chemical
Engineering, Guangxi University, Nanning 530004, China
| | - Wei Lai Wang
- College of Chemistry and Chemical
Engineering, Guangxi University, Nanning 530004, China
| | - Xing Xing Ning
- College of Chemistry and Chemical
Engineering, Guangxi University, Nanning 530004, China
| | - Yao Liu
- College of Chemistry and Chemical
Engineering, Guangxi University, Nanning 530004, China
| | - Shu Kai Zhao
- College of Chemistry and Chemical
Engineering, Guangxi University, Nanning 530004, China
| | - Yong-An Guo
- College of Chemistry and Chemical
Engineering, Guangxi University, Nanning 530004, China
| | - Su Juan Wei
- College of Chemistry and Chemical
Engineering, Guangxi University, Nanning 530004, China
| | - Hong Zhou
- College of Chemistry and Chemical
Engineering, Guangxi University, Nanning 530004, China
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31
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Zhao Y, Du KJ, Gao SQ, He B, Wen GB, Tan X, Lin YW. Distinct mechanisms for DNA cleavage by myoglobin with a designed heme active center. J Inorg Biochem 2016; 156:113-21. [DOI: 10.1016/j.jinorgbio.2016.01.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2015] [Revised: 12/29/2015] [Accepted: 01/07/2016] [Indexed: 12/14/2022]
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Reengineering cyt b562 for hydrogen production: A facile route to artificial hydrogenases. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2015; 1857:598-603. [PMID: 26375327 DOI: 10.1016/j.bbabio.2015.09.001] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Accepted: 09/09/2015] [Indexed: 11/20/2022]
Abstract
Bioinspired, protein-based molecular catalysts utilizing base metals at the active are emerging as a promising avenue to sustainable hydrogen production. The protein matrix modulates the intrinsic reactivity of organometallic active sites by tuning second-sphere and long-range interactions. Here, we show that swapping Co-Protoporphyrin IX for Fe-Protoporphyrin IX in cytochrome b562 results in an efficient catalyst for photoinduced proton reduction to molecular hydrogen. Further, the activity of wild type Co-cyt b562 can be modulated by a factor of 2.5 by exchanging the coordinating methionine with alanine or aspartic acid. The observed turnover numbers (TON) range between 125 and 305, and correlate well with the redox potential of the Co-cyt b562 mutants. The photosensitized system catalyzes proton reduction with high efficiency even under an aerobic atmosphere, implicating its use for biotechnological applications. This article is part of a Special Issue entitled Biodesign for Bioenergetics--the design and engineering of electronic transfer cofactors, proteins and protein networks, edited by Ronald L. Koder and J.L. Ross Anderson.
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Lin YW. The broad diversity of heme-protein cross-links: An overview. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2015; 1854:844-59. [DOI: 10.1016/j.bbapap.2015.04.019] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2015] [Revised: 03/26/2015] [Accepted: 04/17/2015] [Indexed: 12/30/2022]
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Hydrogen bond donation to the heme distal ligand of Staphylococcus aureus IsdG tunes the electronic structure. J Biol Inorg Chem 2015; 20:757-70. [DOI: 10.1007/s00775-015-1263-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Accepted: 04/13/2015] [Indexed: 10/23/2022]
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35
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Yan DJ, Li W, Xiang Y, Wen GB, Lin YW, Tan X. A Novel Tyrosine-Heme CO Covalent Linkage in F43Y Myoglobin: A New Post-translational Modification of Heme Proteins. Chembiochem 2014; 16:47-50. [DOI: 10.1002/cbic.201402504] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2014] [Indexed: 12/18/2022]
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36
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Lin YW, Nagao S, Zhang M, Shomura Y, Higuchi Y, Hirota S. Rational design of heterodimeric protein using domain swapping for myoglobin. Angew Chem Int Ed Engl 2014; 54:511-5. [PMID: 25370865 DOI: 10.1002/anie.201409267] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2014] [Indexed: 11/12/2022]
Abstract
Protein design is a useful method to create novel artificial proteins. A rational approach to design a heterodimeric protein using domain swapping for horse myoglobin (Mb) was developed. As confirmed by X-ray crystallographic analysis, a heterodimeric Mb with two different active sites was produced efficiently from two surface mutants of Mb, in which the charges of two amino acids involved in the dimer salt bridges were reversed in each mutant individually, with the active site of one mutant modified. This study shows that the method of constructing heterodimeric Mb with domain swapping is useful for designing artificial multiheme proteins.
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Affiliation(s)
- Ying-Wu Lin
- Graduate School of Materials Science, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara, 630-0192 (Japan); School of Chemistry and Chemical Engineering, University of South China, Hengyang 421001 (China)
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37
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Lin YW, Nagao S, Zhang M, Shomura Y, Higuchi Y, Hirota S. Rational Design of Heterodimeric Protein using Domain Swapping for Myoglobin. Angew Chem Int Ed Engl 2014. [DOI: 10.1002/ange.201409267] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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38
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Owens CP, Chim N, Graves AB, Harmston CA, Iniguez A, Contreras H, Liptak MD, Goulding CW. The Mycobacterium tuberculosis secreted protein Rv0203 transfers heme to membrane proteins MmpL3 and MmpL11. J Biol Chem 2013; 288:21714-28. [PMID: 23760277 DOI: 10.1074/jbc.m113.453076] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Mycobacterium tuberculosis is the causative agent of tuberculosis, which is becoming an increasingly global public health problem due to the rise of drug-resistant strains. While residing in the human host, M. tuberculosis needs to acquire iron for its survival. M. tuberculosis has two iron uptake mechanisms, one that utilizes non-heme iron and another that taps into the vast host heme-iron pool. To date, proteins known to be involved in mycobacterial heme uptake are Rv0203, MmpL3, and MmpL11. Whereas Rv0203 transports heme across the bacterial periplasm or scavenges heme from host heme proteins, MmpL3 and MmpL11 are thought to transport heme across the membrane. In this work, we characterize the heme-binding properties of the predicted extracellular soluble E1 domains of both MmpL3 and MmpL11 utilizing absorption, electron paramagnetic resonance, and magnetic circular dichroism spectroscopic methods. Furthermore, we demonstrate that Rv0203 transfers heme to both MmpL3-E1 and MmpL11-E1 domains at a rate faster than passive heme dissociation from Rv0203. This work elucidates a key step in the mycobacterial uptake of heme, and it may be useful in the development of anti-tuberculosis drugs targeting this pathway.
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Affiliation(s)
- Cedric P Owens
- Department of Molecular Biology and Biochemistry, University of California at Irvine, Irvine, California 92697, USA
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39
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Mono- and bis-phosphine-ligated H93G myoglobin: spectral models for ferrous-phosphine and ferrous-CO cytochrome P450. J Inorg Biochem 2013; 127:238-45. [PMID: 23639797 DOI: 10.1016/j.jinorgbio.2013.03.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2012] [Revised: 03/13/2013] [Accepted: 03/13/2013] [Indexed: 11/21/2022]
Abstract
To further investigate the properties of phosphines as structural and functional probes of heme proteins, mono- and bis-phosphine [tris(hydroxymethyl)phosphine, THMP] adducts of H93G myoglobin (Mb) have been prepared by stepwise THMP titrations of exogenous ligand-free ferric and ferrous H93G Mb, respectively. Bubbling with CO or stepwise titration with imidazole (Im) of the bis-THMP-ligated ferrous protein generated a mixed ligand (THMP/CO or THMP/Im, respectively) ferrous complexes. Stable oxyferrous H93G(THMP) Mb was formed at -40°C by bubbling the mono-THMP-Fe(II) protein with O2. A THMP-ligated ferryl H93G Mb moiety has been partially formed upon addition of H2O2 to the ferric mono-THMP adduct. All the species prepared above have been characterized with UV-visible (UV-vis) absorption and magnetic circular dichroism (MCD) spectroscopy in this study. The six-coordinate ferrous bis-phosphine and mono-phosphine/CO complexes of H93G Mb exhibit characteristic spectral features (red-shifted Soret/unique-shaped MCD visible bands and hyperporphyrin spectra, respectively) that only have been seen for the analogous phosphine or CO-complexes of thiolate-ligated heme proteins such as cytochrome P450 (P450) and Caldariomyces fumago chloroperoxidase (CPO). However, such resemblance is not seen in phosphine-ligated ferric H93G Mb even though phosphine-bound ferric P450 and CPO display hyperporphyrin spectra. In fact, bis-THMP-bound ferric H93G Mb exhibits MCD and UV-vis absorption spectra that are similar to those of bis-amine- and bis-thioether-ligated H93G Mb complexes. This study also further demonstrates the utility of the H93G cavity mutant for preparing novel heme iron coordination structures.
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Bradley JM, Marritt SJ, Kihlken MA, Haynes K, Hemmings AM, Berks BC, Cheesman MR, Butt JN. Redox and chemical activities of the hemes in the sulfur oxidation pathway enzyme SoxAX. J Biol Chem 2012; 287:40350-9. [PMID: 23060437 DOI: 10.1074/jbc.m112.396192] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
BACKGROUND SoxAX enzymes initiate microbial oxidation of reduced inorganic sulfur compounds. Their catalytic mechanism is unknown. RESULTS Cyanide displaces the CysS(-) ligand to the active site heme following reduction by S(2)O(4)(2-) but not Eu(II). CONCLUSION An active site heme ligand becomes labile on exposure to substrate analogs. SIGNIFICANCE Elucidation of SoxAX mechanism is necessary to understand a widespread pathway for sulfur compound oxidation. SoxAX enzymes couple disulfide bond formation to the reduction of cytochrome c in the first step of the phylogenetically widespread Sox microbial sulfur oxidation pathway. Rhodovulum sulfidophilum SoxAX contains three hemes. An electrochemical cell compatible with magnetic circular dichroism at near infrared wavelengths has been developed to resolve redox and chemical properties of the SoxAX hemes. In combination with potentiometric titrations monitored by electronic absorbance and EPR, this method defines midpoint potentials (E(m)) at pH 7.0 of approximately +210, -340, and -400 mV for the His/Met, His/Cys(-), and active site His/CysS(-)-ligated heme, respectively. Exposing SoxAX to S(2)O(4)(2-), a substrate analog with E(m) ~-450 mV, but not Eu(II) complexed with diethylene triamine pentaacetic acid (E(m) ~-1140 mV), allows cyanide to displace the cysteine persulfide (CysS(-)) ligand to the active site heme. This provides the first evidence for the dissociation of CysS(-) that has been proposed as a key event in SoxAX catalysis.
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Affiliation(s)
- Justin M Bradley
- Centre for Molecular and Structural Biochemistry, School of Chemistry and School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK
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41
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Rose MJ, Bellone DE, Di Bilio AJ, Gray HB. Spectroscopic and magnetic properties of an iodo Co(I) tripodal phosphine complex. Dalton Trans 2012; 41:11788-97. [PMID: 22903546 DOI: 10.1039/c2dt31229h] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Reaction of the tripodal phosphine ligand 1,1,1-tris((diphenylphosphino)phenyl)ethane (PhP3) with CoI(2) spontaneously generates a one-electron reduced complex, [(PhP3)Co(I)(I)] (1). The crystal structure of 1 reveals a distorted tetrahedral environment, with an apical Co-I bond distance of ~2.52 Å. Co(II/I) redox occurs at an unusually high potential (+0.38 V vs. SCE). The electronic absorption spectrum of 1 exhibits an MLCT peak at 320 nm (ε = 8790 M(-1) cm(-1)) and a d-d feature at 850 nm (ε = 840 M(-1) cm(-1)). Two more d-d bands are observed in the NIR region, 8650 (ε = 450) and 7950 cm(-1) (ε = 430 M(-1) cm(-1)). Temperature dependent magnetic measurements (SQUID) on 1 (solid state, 20-300 K) give μ(eff) = 2.99(6) μ(B), consistent with an S = 1 ground state. Magnetic susceptibilities below 20 K are consistent with a zero field splitting (zfs) |D| = 8 cm(-1). DFT calculations also support a spin-triplet ground state for 1, as optimized (6-31G*/PW91) geometries (S = 1) closely match the X-ray structure. EPR measurements performed in parallel mode (X-band; 0-15,000 G, 15 K) on polycrystalline 1 or frozen solutions of 1 (THF/toluene) exhibit a feature at g≈ 4 that arises from a (Δm = 2) transition within the M(S) = <+1,-1> manifold. Below 10 K, the EPR signal decreases significantly, consistent with a solution zfs parameter (|D|≈ 8 cm(-1)) similar to that obtained from SQUID measurements. Our work provides an EPR signature for high-spin Co(I) in trigonal ligation.
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Affiliation(s)
- Michael J Rose
- Beckman Institute, California Institute of Technology, Pasadena, CA 91125, USA
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42
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Battistuzzi G, Bortolotti CA, Bellei M, Di Rocco G, Salewski J, Hildebrandt P, Sola M. Role of Met80 and Tyr67 in the Low-pH Conformational Equilibria of Cytochrome c. Biochemistry 2012; 51:5967-78. [DOI: 10.1021/bi3007302] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Gianantonio Battistuzzi
- Department
of Chemistry, University of Modena and Reggio Emilia, via Campi 183,
41100 Modena, Italy
| | - Carlo Augusto Bortolotti
- Department
of Chemistry, University of Modena and Reggio Emilia, via Campi 183,
41100 Modena, Italy
| | - Marzia Bellei
- Department
of Chemistry, University of Modena and Reggio Emilia, via Campi 183,
41100 Modena, Italy
| | - Giulia Di Rocco
- Department
of Chemistry, University of Modena and Reggio Emilia, via Campi 183,
41100 Modena, Italy
| | - Johannes Salewski
- Technische Universität Berlin, Institut für Chemie, Sekr. PC14, Straße
des 17. Juni 135, D-10623 Berlin, Germany
| | - Peter Hildebrandt
- Technische Universität Berlin, Institut für Chemie, Sekr. PC14, Straße
des 17. Juni 135, D-10623 Berlin, Germany
| | - Marco Sola
- Department
of Chemistry, University of Modena and Reggio Emilia, via Campi 183,
41100 Modena, Italy
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43
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Rebouças JS, Patrick BO, James BR. Thiol, disulfide, and trisulfide complexes of Ru porphyrins: potential models for iron-sulfur bonds in heme proteins. J Am Chem Soc 2012; 134:3555-70. [PMID: 22224472 DOI: 10.1021/ja211226e] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Thirty-two Ru(porp)L(2) complexes have been synthesized, where porp = the dianion of meso-tetramesitylporphyrin (TMP) or meso-tetrakis(4-methylphenyl)porphyrin (H(2)T-pMe-PP), and L = a thiol, a sulfide, a disulfide, or a trisulfide. Species studied were with RSH [R = Me, Et, (n)Pr, (i)Pr, (t)Bu, Bn (benzyl), and Ph], RSR (R = Me, Bn), RSSR (R = Me, Et, (n)Pr, Bn) and MeSS(t)Bu, and RSSSR (R = Me, Bn). All the species except two, which were the isolated Ru(T-pMe-PP)((t)BuSH)(2) and Ru(TMP)(MeSSMe)(2), were characterized in situ. The disulfide complex was characterized by X-ray analysis. (1)H NMR data for the coordinated thiols are the first reported within metalloporphyrin systems, and are especially informative because of the upfield shifts of the axial sulfur-containing ligands due to the porphyrin π-ring current effect, which is also present in the di- and trisulfide species. The disulfide in the solid state structure of Ru(TMP)(MeSSMe)(2) is η(1)(end-on) coordinated, the first example of such bonding in a nontethered, acyclic dialkyl disulfide; (1)H-(1)H EXSY NMR data in solution show that the species undergoes 1,2-S-metallotropic shifts. Stepwise formation of the bis(disulfide) complex from Ru(TMP)(MeCN)(2) in solution occurs with a cooperativity effect, resembling behavior of Fe(II)-porphyrin systems where crystal field effects dominate, but ligand trans-effects are more likely in the Ru system. The η(1)(end-on) coordination mode is also favored for the trisulfide ligand. Discussed also are the remarkable linear correlations that exist between the ring-current shielding shifts for the axial ligand C(1) protons of Ru(porp)(RS(x)R)(2) and x (the number of S atoms). The Introduction briefly reviews literature on Ru- and Fe porphyrins (including heme proteins) with sulfur-containing ligands or substrates, and relationships between our findings and this literature are discussed throughout the paper.
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Affiliation(s)
- Júlio S Rebouças
- Departamento de Química, CCEN, Universidade Federal da Paraíba, João Pessoa, PB, 58.051-900, Brazil.
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44
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Nagao S, Osuka H, Yamada T, Uni T, Shomura Y, Imai K, Higuchi Y, Hirota S. Structural and oxygen binding properties of dimeric horse myoglobin. Dalton Trans 2012; 41:11378-85. [DOI: 10.1039/c2dt30893b] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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