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Bradley JM, Bugg Z, Sackey A, Andrews SC, Wilson MT, Svistunenko DA, Moore GR, Le Brun NE. The Ferroxidase Centre of Escherichia coli Bacterioferritin Plays a Key Role in the Reductive Mobilisation of the Mineral Iron Core. Angew Chem Int Ed Engl 2024; 63:e202401379. [PMID: 38407997 DOI: 10.1002/anie.202401379] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2024] [Revised: 02/22/2024] [Accepted: 02/22/2024] [Indexed: 02/28/2024]
Abstract
Ferritins are multimeric cage-forming proteins that play a crucial role in cellular iron homeostasis. All H-chain-type ferritins harbour a diiron site, the ferroxidase centre, at the centre of a 4 α-helical bundle, but bacterioferritins are unique in also binding 12 hemes per 24 meric assembly. The ferroxidase centre is known to be required for the rapid oxidation of Fe2+ during deposition of an immobilised ferric mineral core within the protein's hollow interior. In contrast, the heme of bacterioferritin is required for the efficient reduction of the mineral core during iron release, but has little effect on the rate of either oxidation or mineralisation of iron. Thus, the current view is that these two cofactors function in iron uptake and release, respectively, with no functional overlap. However, rapid electron transfer between the heme and ferroxidase centre of bacterioferritin from Escherichia coli was recently demonstrated, suggesting that the two cofactors may be functionally connected. Here we report absorbance and (magnetic) circular dichroism spectroscopies, together with in vitro assays of iron-release kinetics, which demonstrate that the ferroxidase centre plays an important role in the reductive mobilisation of the bacterioferritin mineral core, which is dependent on the heme-ferroxidase centre electron transfer pathway.
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Affiliation(s)
- Justin M Bradley
- Centre for Molecular and Structural Biochemistry, School of Chemistry, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK
| | - Zinnia Bugg
- Centre for Molecular and Structural Biochemistry, School of Chemistry, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK
| | - Aaren Sackey
- Centre for Molecular and Structural Biochemistry, School of Chemistry, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK
| | - Simon C Andrews
- School of Biological Sciences, University of Reading, Whiteknights, Reading, RG6 6AS, UK
| | - Michael T Wilson
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester, CO4 3SQ, UK
| | - Dimitri A Svistunenko
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester, CO4 3SQ, UK
| | - Geoffrey R Moore
- Centre for Molecular and Structural Biochemistry, School of Chemistry, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK
| | - Nick E Le Brun
- Centre for Molecular and Structural Biochemistry, School of Chemistry, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK
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2
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Gu G, Liu C, Lee SH, Chun Choi LS, Wilson MT, Pfeiffer DU, Go YY. Detection of a reassortant swine H1N2 influenza A virus from pigs in Hong Kong. Virol Sin 2024; 39:343-346. [PMID: 38309471 DOI: 10.1016/j.virs.2024.01.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Accepted: 01/26/2024] [Indexed: 02/05/2024] Open
Affiliation(s)
- Guoqian Gu
- Department of Infectious Diseases and Public Health, Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Hong Kong SAR, China
| | - Congnuan Liu
- Department of Infectious Diseases and Public Health, Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Hong Kong SAR, China
| | - Song Hao Lee
- Center for Applied One Health Research and Policy Advice, Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Hong Kong SAR, China
| | - Lewis Sze Chun Choi
- Center for Applied One Health Research and Policy Advice, Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Hong Kong SAR, China
| | - Michael T Wilson
- Center for Applied One Health Research and Policy Advice, Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Hong Kong SAR, China
| | - Dirk U Pfeiffer
- Department of Infectious Diseases and Public Health, Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Hong Kong SAR, China; Center for Applied One Health Research and Policy Advice, Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Hong Kong SAR, China
| | - Yun Young Go
- Department of Infectious Diseases and Public Health, Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Hong Kong SAR, China; College of Veterinary Medicine, Konkuk University, Seoul, 143-701, Republic of Korea.
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3
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Lučić M, Wilson MT, Pullin J, Hough MA, Svistunenko DA, Worrall JAR. New insights into controlling radical migration pathways in heme enzymes gained from the study of a dye-decolorising peroxidase. Chem Sci 2023; 14:12518-12534. [PMID: 38020392 PMCID: PMC10646903 DOI: 10.1039/d3sc04453j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Accepted: 10/06/2023] [Indexed: 12/01/2023] Open
Abstract
In heme enzymes, such as members of the dye-decolorising peroxidase (DyP) family, the formation of the highly oxidising catalytic Fe(iv)-oxo intermediates following reaction with hydrogen peroxide can lead to free radical migration (hole hopping) from the heme to form cationic tyrosine and/or tryptophan radicals. These species are highly oxidising (∼1 V vs. NHE) and under certain circumstances can catalyse the oxidation of organic substrates. Factors that govern which specific tyrosine or tryptophan the free radical migrates to in heme enzymes are not well understood, although in the case of tyrosyl radical formation the nearby proximity of a proton acceptor is a recognised facilitating factor. By using an A-type member of the DyP family (DtpAa) as an exemplar, we combine protein engineering, X-ray crystallography, hole-hopping calculations, EPR spectroscopy and kinetic modelling to provide compelling new insights into the control of radical migration pathways following reaction of the heme with hydrogen peroxide. We demonstrate that the presence of a tryptophan/tyrosine dyad motif displaying a T-shaped orientation of aromatic rings on the proximal side of the heme dominates the radical migration landscape in wild-type DtpAa and continues to do so following the rational engineering into DtpAa of a previously identified radical migration pathway in an A-type homolog on the distal side of the heme. Only on disrupting the proximal dyad, through removal of an oxygen atom, does the radical migration pathway then switch to the engineered distal pathway to form the desired tyrosyl radical. Implications for protein design and biocatalysis are discussed.
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Affiliation(s)
- Marina Lučić
- School of Life Sciences, University of Essex Wivenhoe Park Colchester Essex CO4 3SQ UK
| | - Michael T Wilson
- School of Life Sciences, University of Essex Wivenhoe Park Colchester Essex CO4 3SQ UK
| | - Jacob Pullin
- School of Life Sciences, University of Essex Wivenhoe Park Colchester Essex CO4 3SQ UK
| | - Michael A Hough
- School of Life Sciences, University of Essex Wivenhoe Park Colchester Essex CO4 3SQ UK
- Diamond Light Source, Harwell Science and Innovation Campus Didcot Oxfordshire OX11 0DE UK
| | - Dimitri A Svistunenko
- School of Life Sciences, University of Essex Wivenhoe Park Colchester Essex CO4 3SQ UK
| | - Jonathan A R Worrall
- School of Life Sciences, University of Essex Wivenhoe Park Colchester Essex CO4 3SQ UK
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4
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Adams HR, Svistunenko DA, Wilson MT, Fujii S, Strange RW, Hardy ZA, Vazquez PA, Dabritz T, Streblow GJ, Andrew CR, Hough MA. A Heme Pocket Aromatic Quadrupole Modulates Gas Binding to Cytochrome c'-β: Implications for NO Sensors. J Biol Chem 2023:104742. [PMID: 37100286 DOI: 10.1016/j.jbc.2023.104742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Revised: 04/15/2023] [Accepted: 04/19/2023] [Indexed: 04/28/2023] Open
Abstract
The structural basis by which gas-binding heme proteins control their interactions with NO, CO, and O2, is fundamental to enzymology, biotechnology and human health. Cytochromes c´ (cyts c´) are a group of putative NO-binding heme proteins that fall into two families: the well characterised four alpha helix bundle fold (cyts c´-α) and an unrelated family with a largely beta sheet fold (cyts c´-β) resembling that of cytochromes P460. A recent structure of cyt c´-β from Methylococcus capsulatus Bath (McCP-β) revealed two heme pocket phenylalanine residues (Phe 32 and Phe 61) positioned near the distal gas binding site. This feature, dubbed the "Phe cap", is highly conserved within the sequences of other cyts c´-β, but is absent in their close homologues, the hydroxylamine oxidizing cytochromes P460, although some do contain a single Phe residue. Here we report an integrated structural, spectroscopic, and kinetic characterization of McCP-β complexes with diatomic gases, focusing on the interaction of the Phe cap with NO and CO. Significantly, crystallographic and resonance Raman data show that orientation of the electron rich aromatic ring face of Phe 32 towards distally-bound NO or CO is associated with weakened backbonding and higher off rates. Moreover, we propose that an aromatic quadrupole also contributes to the unusually weak backbonding reported for some heme-based gas sensors, including the mammalian NO-sensor, soluble guanylate cyclase (sGC). Collectively, this study sheds light on the influence of highly conserved distal Phe residues on heme-gas complexes of cytochrome c'-β, including the potential for aromatic quadrupoles to modulate NO and CO binding in other heme proteins.
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Affiliation(s)
- Hannah R Adams
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester, Essex, CO4 3SQ, UK
| | - Dimitri A Svistunenko
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester, Essex, CO4 3SQ, UK
| | - Michael T Wilson
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester, Essex, CO4 3SQ, UK
| | - Sotaro Fujii
- Graduate School of Biosphere Science, Hiroshima University, Kagamiyama 1-4-4, Higashi-Hiroshima, Hiroshima, 739-8528, Japan; Diamond Light Source Ltd., Harwell Science and Innovation Campus, Didcot OX11 0DE, UK
| | - Richard W Strange
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester, Essex, CO4 3SQ, UK
| | - Zoe A Hardy
- Department of Chemistry & Biochemistry, Eastern Oregon University, La Grande OR 97850, USA
| | - Priscilla A Vazquez
- Department of Chemistry & Biochemistry, Eastern Oregon University, La Grande OR 97850, USA
| | - Tyler Dabritz
- Department of Chemistry & Biochemistry, Eastern Oregon University, La Grande OR 97850, USA
| | - Gabriel J Streblow
- Department of Chemistry & Biochemistry, Eastern Oregon University, La Grande OR 97850, USA
| | - Colin R Andrew
- Department of Chemistry & Biochemistry, Eastern Oregon University, La Grande OR 97850, USA.
| | - Michael A Hough
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester, Essex, CO4 3SQ, UK; Diamond Light Source Ltd., Harwell Science and Innovation Campus, Didcot OX11 0DE, UK.
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Silver J, al-Jaff G, Taies JA, Wilson MT, den Engelsen D, Fern GR, Ireland TG. Studies on the binding of CO to low-spin [Fe(II)(Por)L 2] complexes: an aid to understanding the binding of CO to haemoglobin and myoglobin. J Biol Inorg Chem 2023; 28:65-84. [PMID: 36478266 PMCID: PMC9938061 DOI: 10.1007/s00775-022-01969-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Accepted: 10/13/2022] [Indexed: 12/12/2022]
Abstract
The visible and Mössbauer spectra of [Fe(II)(Por)L2] and [Fe(II)(Por)L(CO)] complexes (where Por = protoporphyrin IX (PPIX) or tetra(p-sulfophenyl)porphyrin (TPPS) and L = an aliphatic or aromatic nitrogenous base) are reported and discussed. The results are compared to those of previously reported [Fe(II)(Por)L(CO)] complexes (where Por = PPIX, TPPS, PMXPP, TPP, OMTBP and OEP; L = a nitrogenous aromatic ligand) and HbCO (where Hb = haemoglobin) and MyCO (where My = myoglobin). A new approach, to extracting information from the Mössbauer parameters has been developed by plotting those of the [Fe(II)(Por)L2] complexes against those of [Fe(II)(Por)L(CO)] complexes for the same ligands, has yielded a series of trend lines that show a significant dependence on both the nature of the porphyrin and also of the nitrogenous ligand. Different trend lines were found for aromatic nitrogenous ligands to aliphatic nitrogenous ligands showing that the porphyrins could donate different amounts of charge to the Fe(II) cations as the L ligand changed, and hence, they display electron sink properties. From the plots, it was shown that haemoglobin and myoglobin both bind CO very strongly compared to the model complexes studied herein. Using the reported structural and Mössbauer data for the [Fe(II)(Por)L2] and [Fe(II)(Por)L(CO)] complexes, it proved possible and instructive to plot the Mössbauer parameters against a number of the bond lengths around the Fe(II) cations. The interpretation of the resulting trend lines both supported and facilitated the extension of our findings enabling further understanding of the geometry of the bonding in CO haemoglobin and CO myoglobin.
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Affiliation(s)
- Jack Silver
- grid.7728.a0000 0001 0724 6933College of Engineering, Design and Physical Sciences, School of Engineering, Wolfson Centre for Materials Processing, Brunel University London, Kingston Lane, Uxbridge, UB8 3PH Middlesex UK
| | - Golzar al-Jaff
- grid.8356.80000 0001 0942 6946School of Life Sciences, University of Essex, Wivenhoe Park, Colchester, CO4 3SQ Essex UK ,grid.444950.8Department of Chemistry, College of Education, Salahaddin University-Erbil, Erbil, Iraq
| | - Jehad A. Taies
- grid.8356.80000 0001 0942 6946School of Life Sciences, University of Essex, Wivenhoe Park, Colchester, CO4 3SQ Essex UK ,Department of Chemistry, College of Education for Pure Science, University of Anwar, Ramadi, Iraq
| | - Michael T. Wilson
- grid.8356.80000 0001 0942 6946School of Life Sciences, University of Essex, Wivenhoe Park, Colchester, CO4 3SQ Essex UK
| | - Daniel den Engelsen
- grid.7728.a0000 0001 0724 6933College of Engineering, Design and Physical Sciences, School of Engineering, Wolfson Centre for Materials Processing, Brunel University London, Kingston Lane, Uxbridge, UB8 3PH Middlesex UK
| | - George R. Fern
- grid.7728.a0000 0001 0724 6933College of Engineering, Design and Physical Sciences, School of Engineering, Wolfson Centre for Materials Processing, Brunel University London, Kingston Lane, Uxbridge, UB8 3PH Middlesex UK
| | - Terry G. Ireland
- grid.7728.a0000 0001 0724 6933College of Engineering, Design and Physical Sciences, School of Engineering, Wolfson Centre for Materials Processing, Brunel University London, Kingston Lane, Uxbridge, UB8 3PH Middlesex UK
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6
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Lučić M, Wilson MT, Tosha T, Sugimoto H, Shilova A, Axford D, Owen RL, Hough MA, Worrall JAR. Serial Femtosecond Crystallography Reveals the Role of Water in the One- or Two-Electron Redox Chemistry of Compound I in the Catalytic Cycle of the B-Type Dye-Decolorizing Peroxidase DtpB. ACS Catal 2022; 12:13349-13359. [PMID: 36366763 PMCID: PMC9638988 DOI: 10.1021/acscatal.2c03754] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Revised: 10/05/2022] [Indexed: 11/30/2022]
Abstract
![]()
Controlling the reactivity
of high-valent Fe(IV)–O
catalytic
intermediates, Compounds I and II, generated in heme enzymes upon
reaction with dioxygen or hydrogen peroxide, is important for function.
It has been hypothesized that the presence (wet) or absence (dry)
of distal heme pocket water molecules can influence whether Compound
I undergoes sequential one-electron additions or a concerted two-electron
reduction. To test this hypothesis, we investigate the role of water
in the heme distal pocket of a dye-decolorizing peroxidase utilizing
a combination of serial femtosecond crystallography and rapid kinetic
studies. In a dry distal heme site, Compound I reduction proceeds
through a mechanism in which Compound II concentration is low. This
reaction shows a strong deuterium isotope effect, indicating that
reduction is coupled to proton uptake. The resulting protonated Compound
II (Fe(IV)–OH) rapidly reduces to the ferric state, giving
the appearance of a two-electron transfer process. In a wet site,
reduction of Compound I is faster, has no deuterium effect, and yields
highly populated Compound II, which is subsequently reduced to the
ferric form. This work provides a definitive experimental test of
the hypothesis advanced in the literature that relates sequential
or concerted electron transfer to Compound I in wet or dry distal
heme sites.
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Affiliation(s)
- Marina Lučić
- School of Life Sciences, University of Essex, Wivenhoe Park,
Essex, ColchesterCO4 3SQ, U.K
| | - Michael T. Wilson
- School of Life Sciences, University of Essex, Wivenhoe Park,
Essex, ColchesterCO4 3SQ, U.K
| | - Takehiko Tosha
- RIKEN, Spring-8 Center, 1-1-1 Kouto, Sayo, Hyogo679-5148Japan
| | | | - Anastasya Shilova
- Diamond Light Source, Harwell Science and Innovation Campus, Oxfordshire, DidcotOX11 0DE, U.K
| | - Danny Axford
- Diamond Light Source, Harwell Science and Innovation Campus, Oxfordshire, DidcotOX11 0DE, U.K
| | - Robin L. Owen
- Diamond Light Source, Harwell Science and Innovation Campus, Oxfordshire, DidcotOX11 0DE, U.K
| | - Michael A. Hough
- School of Life Sciences, University of Essex, Wivenhoe Park,
Essex, ColchesterCO4 3SQ, U.K
- Diamond Light Source, Harwell Science and Innovation Campus, Oxfordshire, DidcotOX11 0DE, U.K
| | - Jonathan A. R. Worrall
- School of Life Sciences, University of Essex, Wivenhoe Park,
Essex, ColchesterCO4 3SQ, U.K
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Ukeri J, Wilson MT, Reeder BJ. Modulating Nitric Oxide Dioxygenase and Nitrite Reductase of Cytoglobin through Point Mutations. Antioxidants (Basel) 2022; 11:antiox11091816. [PMID: 36139890 PMCID: PMC9495915 DOI: 10.3390/antiox11091816] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 09/02/2022] [Accepted: 09/09/2022] [Indexed: 11/16/2022] Open
Abstract
Cytoglobin is a hexacoordinate hemoglobin with physiological roles that are not clearly understood. Previously proposed physiological functions include nitric oxide regulation, oxygen sensing, or/and protection against oxidative stress under hypoxic/ischemic conditions. Like many globins, cytoglobin rapidly consumes nitric oxide under normoxic conditions. Under hypoxia, cytoglobin generates nitric oxide, which is strongly modulated by the oxidation state of the cysteines. This gives a plausible role for this biochemistry in controlling nitric oxide homeostasis. Mutations to control specific properties of hemoglobin and myoglobin, including nitric oxide binding/scavenging and the nitrite reductase activity of various globins, have been reported. We have mapped these key mutations onto cytoglobin, which represents the E7 distal ligand, B2/E9 disulfide, and B10 heme pocket residues, and examined the nitric oxide binding, nitric oxide dioxygenase activity, and nitrite reductase activity. The Leu46Trp mutation decreases the nitric oxide dioxygenase activity > 10,000-fold over wild type, an effect 1000 times greater than similar mutations with other globins. By understanding how particular mutations can affect specific reactivities, these mutations may be used to target specific cytoglobin activities in cell or animal models to help understand the precise role(s) of cytoglobin under physiological and pathophysiological conditions.
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Alayash AI, Wilson MT. Hemoglobin can Act as a (Pseudo)-Peroxidase in Vivo. What is the Evidence? Front Mol Biosci 2022; 9:910795. [PMID: 35832737 PMCID: PMC9271945 DOI: 10.3389/fmolb.2022.910795] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Accepted: 05/31/2022] [Indexed: 11/13/2022] Open
Affiliation(s)
- Abdu I. Alayash
- Laboratory of Biochemistry and Vascular Biology, Division of Blood Components and Devices (DBCD), Center for Biologics Evaluation and Research (CBER), Food and Drug Administration (FDA), Silver Spring, MD, United States
- *Correspondence: Abdu I. Alayash,
| | - Michael T. Wilson
- School of Life Sciences, University of Essex, Wivenhoe Park, United Kingdom
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9
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Silver J, Al-Jaff G, Wilson MT, den Engelsen D, Fern GR, Ireland TG. Studies on the binding of nitrogenous bases to protoporphyrin IX iron(II) in aqueous solution at high pH values. J Biol Inorg Chem 2022; 27:297-313. [PMID: 35235042 PMCID: PMC8960585 DOI: 10.1007/s00775-022-01929-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Accepted: 01/14/2022] [Indexed: 10/28/2022]
Abstract
Studies are reported on the formation of low-spin six-coordinate [Fe(PPIX)L2] complexes from iron(II) protoporphyrin where L is one of a series of nitrogenous ligands (aliphatic, aromatic or heterocyclic). The bonding constants have been determined by titration of the metal complex with these ligands and are compared in relation to previous studies. The adduct formation was monitored utilising optical spectroscopy. In addition, Mӧssbauer spectroscopic experiments were conducted to monitor the electronic environment around the central iron atom in these complexes. The two complementary spectroscopic methods indicated that all nitrogen ligands formed low-spin octahedral complexes. The magnitude of the overall binding constants (β2 values) are discussed and related to (a) the pKa values of the free ligands and (b) the Mössbauer parameter ΔEQ, which represents the quadrupole splitting of the haem iron. The β2 and ΔEQ values are also discussed in terms of the structure of the ligand. Cooperative binding was observed for nearly all the ligands with Hill coefficients close to 2 for iron(II) protoporphyrin; one of these ligands displayed a much greater affinity than any we previously studied, and this was a direct consequence of the structure of the ligand. Overall conclusions on these and previous studies are drawn in terms of aliphatic ligands versus aromatic ring structures and the absence or presence of sterically hindered nitrogen atoms. The implications of the work for the greater understanding of haem proteins in general and in particular how the nitrogenous ligand binding results are relevant to and aid the understanding of the binding of inhibitor molecules to the cytochrome P450 mono-oxygenases (for therapeutic purposes) are also discussed. Changes in the electronic absorption spectra of five-coordinate [Fe(II)(PPIX)(2-MeIm)] that occurred as the temperature was lowered from room temperature to 78° K.
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Affiliation(s)
- Jack Silver
- College of Engineering, Design and Physical Sciences, School of Engineering, Wolfson Centre for Materials Processing, Brunel University London, Kingston Lane, Uxbridge, UB8 3PH, Middlesex, UK
| | - Golzar Al-Jaff
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester, CO4 3SQ, Essex, UK.,Department of Chemistry, College of Education, Salahaddin University-Erbil, Erbil, Iraq
| | - Michael T Wilson
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester, CO4 3SQ, Essex, UK
| | - Daniel den Engelsen
- College of Engineering, Design and Physical Sciences, School of Engineering, Wolfson Centre for Materials Processing, Brunel University London, Kingston Lane, Uxbridge, UB8 3PH, Middlesex, UK
| | - George R Fern
- College of Engineering, Design and Physical Sciences, School of Engineering, Wolfson Centre for Materials Processing, Brunel University London, Kingston Lane, Uxbridge, UB8 3PH, Middlesex, UK
| | - Terry G Ireland
- College of Engineering, Design and Physical Sciences, School of Engineering, Wolfson Centre for Materials Processing, Brunel University London, Kingston Lane, Uxbridge, UB8 3PH, Middlesex, UK.
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10
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Villar I, Rubio MC, Calvo-Begueria L, Pérez-Rontomé C, Larrainzar E, Wilson MT, Sandal N, Mur LA, Wang L, Reeder B, Duanmu D, Uchiumi T, Stougaard J, Becana M. Three classes of hemoglobins are required for optimal vegetative and reproductive growth of Lotus japonicus: genetic and biochemical characterization of LjGlb2-1. J Exp Bot 2021; 72:7778-7791. [PMID: 34387337 PMCID: PMC8664582 DOI: 10.1093/jxb/erab376] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Accepted: 08/11/2021] [Indexed: 06/13/2023]
Abstract
Legumes express two major types of hemoglobins, namely symbiotic (leghemoglobins) and non-symbiotic (phytoglobins), with the latter being categorized into three classes according to phylogeny and biochemistry. Using knockout mutants, we show that all three phytoglobin classes are required for optimal vegetative and reproductive development of Lotus japonicus. The mutants of two class 1 phytoglobins showed different phenotypes: Ljglb1-1 plants were smaller and had relatively more pods, whereas Ljglb1-2 plants had no distinctive vegetative phenotype and produced relatively fewer pods. Non-nodulated plants lacking LjGlb2-1 showed delayed growth and alterations in the leaf metabolome linked to amino acid processing, fermentative and respiratory pathways, and hormonal balance. The leaves of mutant plants accumulated salicylic acid and contained relatively less methyl jasmonic acid, suggesting crosstalk between LjGlb2-1 and the signaling pathways of both hormones. Based on the expression of LjGlb2-1 in leaves, the alterations of flowering and fruiting of nodulated Ljglb2-1 plants, the developmental and biochemical phenotypes of the mutant fed on ammonium nitrate, and the heme coordination and reactivity of the protein toward nitric oxide, we conclude that LjGlb2-1 is not a leghemoglobin but an unusual class 2 phytoglobin. For comparison, we have also characterized a close relative of LjGlb2-1 in Medicago truncatula, MtLb3, and conclude that this is an atypical leghemoglobin.
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Affiliation(s)
- Irene Villar
- Departamento de Nutrición Vegetal, Estación Experimental de Aula Dei, Consejo Superior de Investigaciones Científicas, Apartado 13034, 50080 Zaragoza, Spain
| | - Maria C Rubio
- Departamento de Nutrición Vegetal, Estación Experimental de Aula Dei, Consejo Superior de Investigaciones Científicas, Apartado 13034, 50080 Zaragoza, Spain
| | - Laura Calvo-Begueria
- Departamento de Nutrición Vegetal, Estación Experimental de Aula Dei, Consejo Superior de Investigaciones Científicas, Apartado 13034, 50080 Zaragoza, Spain
| | - Carmen Pérez-Rontomé
- Departamento de Nutrición Vegetal, Estación Experimental de Aula Dei, Consejo Superior de Investigaciones Científicas, Apartado 13034, 50080 Zaragoza, Spain
| | - Estibaliz Larrainzar
- Department of Sciences, Institute for Multidisciplinary Research in Applied Biology, Campus Arrosadía, Universidad Pública de Navarra, 31006 Pamplona, Spain
| | - Michael T Wilson
- School of Life Sciences, Essex University, Wivenhoe Park, Colchester CO4 3SQ, UK
| | - Niels Sandal
- Department of Molecular Biology and Genetics, Aarhus University, Gustav Wieds Vej 10, 8000 Aarhus C, Denmark
| | - Luis A Mur
- Aberystwyth University, Institute of Biological, Environmental and Rural Sciences, Aberystwyth, SY23 3DA, Wales, UK
| | - Longlong Wang
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
| | - Brandon Reeder
- School of Life Sciences, Essex University, Wivenhoe Park, Colchester CO4 3SQ, UK
| | - Deqiang Duanmu
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
| | - Toshiki Uchiumi
- Graduate School of Science and Engineering, Kagoshima University, 1-21-35 Korimoto, Kagoshima 890-0065, Japan
| | - Jens Stougaard
- Department of Molecular Biology and Genetics, Aarhus University, Gustav Wieds Vej 10, 8000 Aarhus C, Denmark
| | - Manuel Becana
- Departamento de Nutrición Vegetal, Estación Experimental de Aula Dei, Consejo Superior de Investigaciones Científicas, Apartado 13034, 50080 Zaragoza, Spain
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11
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Flay KJ, Yang DA, Wilson MT, Lee SH, Bhardwaj V, Hill FI, Pfeiffer DU. Absence of serological or molecular evidence of Leptospira infection in farmed swine in the Hong Kong Special Administrative Region. One Health 2021; 13:100321. [PMID: 34504940 PMCID: PMC8411228 DOI: 10.1016/j.onehlt.2021.100321] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 08/24/2021] [Accepted: 08/28/2021] [Indexed: 11/28/2022] Open
Abstract
Leptospirosis is an important zoonotic disease with several maintenance host species including swine. A cross sectional survey was undertaken between January to October 2020 to investigate the prevalence of leptospirosis in farmed swine in the Hong Kong Special Administrative Region (HKSAR) of China. Serum samples were collected from swine on seven farms (15 swine per farm; ten multiparous sows and five twelve-week-old weaners), while kidney samples were collected from 64 swine submitted for routine post-mortem (26 farms; average 2.4 swine per farm, range 1-6). Microscopic agglutination tests (MAT) to a panel of 24 Leptospira antigens did not reveal any evidence of seroconversion at a titre of 1:100. Polymerase chain reaction (PCR) testing of the kidney samples for Leptospira DNA did not detect any evidence of infection. Bayesian methods were used to compute the probability that the leptospirosis prevalence in farmed swine in the HKSAR was <3%, given none of the 105 swine sampled were positive on the MAT. The results of this study demonstrate no serological or molecular evidence of leptospirosis in farmed swine in the HKSAR. Subsequent statistical analysis supports the conclusion that the prevalence of leptospirosis in farmed swine in the HKSAR is negligible at present.
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Affiliation(s)
- Kate J. Flay
- Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Kowloon, Hong Kong, China
| | - Dan A. Yang
- Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Kowloon, Hong Kong, China
| | - Michael T. Wilson
- CityU Centre for Applied One Health Research and Policy Advice, City University of Hong Kong, Kowloon, Hong Kong, China
| | - Song H. Lee
- CityU Centre for Applied One Health Research and Policy Advice, City University of Hong Kong, Kowloon, Hong Kong, China
| | - Vidya Bhardwaj
- CityU Veterinary Diagnostic Laboratory Co, Ltd, City University of Hong Kong, Kowloon, Hong Kong, China
| | - Fraser I. Hill
- CityU Veterinary Diagnostic Laboratory Co, Ltd, City University of Hong Kong, Kowloon, Hong Kong, China
| | - Dirk U. Pfeiffer
- Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Kowloon, Hong Kong, China
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12
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Wilson MT, Reeder BJ. The peroxidatic activities of Myoglobin and Hemoglobin, their pathological consequences and possible medical interventions. Mol Aspects Med 2021; 84:101045. [PMID: 34654576 PMCID: PMC8837633 DOI: 10.1016/j.mam.2021.101045] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Accepted: 09/30/2021] [Indexed: 11/30/2022]
Abstract
Under those pathological conditions in which Myoglobin and Hemoglobin escape their cellular environments and are thus separated from cellular reductive/protective systems, the inherent peroxidase activities of these proteins can be expressed. This activity leads to the formation of the highly oxidizing oxo-ferryl species. Evidence that this happens in vivo is provided by the formation of a covalent bond between the heme group and the protein and this acts as an unambiguous biomarker for the presence of the oxo ferryl form. The peroxidatic activity also leads to the oxidation of lipids, the products of which can be powerful vasoconstrictive agents (e.g. isoprostanes, neuroprostanes). Here we review the evidence that lipid oxidation occurs following rhabdomyolysis and sub-arachnoid hemorrhage and that the products formed from arachidonic acid chains of phospholipids lead, through vasoconstriction, to kidney failure and brain vasospasm. Intervention in these pathological conditions through administration of reducing agents to remove ferryl heme is discussed. Through-protein electron transfer pathways that facilitate ferryl reduction at low reductant concentration have been identified. We conclude with consideration of the therapeutic use of Hemoglobin Based Oxygen carriers and how the toxicity of these may be reduced by engineering such electron transfer pathways into hemoglobin.
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Affiliation(s)
- Michael T Wilson
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester, Essex, CO4 3SQ, UK.
| | - Brandon J Reeder
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester, Essex, CO4 3SQ, UK.
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13
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Lučić M, Wilson MT, Svistunenko DA, Owen RL, Hough MA, Worrall JAR. Aspartate or arginine? Validated redox state X-ray structures elucidate mechanistic subtleties of Fe IV = O formation in bacterial dye-decolorizing peroxidases. J Biol Inorg Chem 2021; 26:743-761. [PMID: 34477969 PMCID: PMC8463360 DOI: 10.1007/s00775-021-01896-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Accepted: 08/23/2021] [Indexed: 11/26/2022]
Abstract
Structure determination of proteins and enzymes by X-ray crystallography remains the most widely used approach to complement functional and mechanistic studies. Capturing the structures of intact redox states in metalloenzymes is critical for assigning the chemistry carried out by the metal in the catalytic cycle. Unfortunately, X-rays interact with protein crystals to generate solvated photoelectrons that can reduce redox active metals and hence change the coordination geometry and the coupled protein structure. Approaches to mitigate such site-specific radiation damage continue to be developed, but nevertheless application of such approaches to metalloenzymes in combination with mechanistic studies are often overlooked. In this review, we summarize our recent structural and kinetic studies on a set of three heme peroxidases found in the bacterium Streptomyces lividans that each belong to the dye decolourizing peroxidase (DyP) superfamily. Kinetically, each of these DyPs has a distinct reactivity with hydrogen peroxide. Through a combination of low dose synchrotron X-ray crystallography and zero dose serial femtosecond X-ray crystallography using an X-ray free electron laser (XFEL), high-resolution structures with unambiguous redox state assignment of the ferric and ferryl (FeIV = O) heme species have been obtained. Experiments using stopped-flow kinetics, solvent-isotope exchange and site-directed mutagenesis with this set of redox state validated DyP structures have provided the first comprehensive kinetic and structural framework for how DyPs can modulate their distal heme pocket Asp/Arg dyad to use either the Asp or the Arg to facilitate proton transfer and rate enhancement of peroxide heterolysis.
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Affiliation(s)
- Marina Lučić
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester, CO4 3SQ, UK
| | - Michael T Wilson
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester, CO4 3SQ, UK
| | - Dimitri A Svistunenko
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester, CO4 3SQ, UK
| | - Robin L Owen
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, OX11 0DE, Oxfordshire, UK
| | - Michael A Hough
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester, CO4 3SQ, UK
| | - Jonathan A R Worrall
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester, CO4 3SQ, UK.
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14
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Pullin J, Wilson MT, Clémancey M, Blondin G, Bradley JM, Moore GR, Le Brun NE, Lučić M, Worrall JAR, Svistunenko DA. Iron Oxidation in Escherichia coli Bacterioferritin Ferroxidase Centre, a Site Designed to React Rapidly with H 2O 2 but Slowly with O 2. Angew Chem Weinheim Bergstr Ger 2021; 133:8442-8450. [PMID: 38529354 PMCID: PMC10962548 DOI: 10.1002/ange.202015964] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 01/05/2021] [Indexed: 11/09/2022]
Abstract
Both O2 and H2O2 can oxidize iron at the ferroxidase center (FC) of Escherichia coli bacterioferritin (EcBfr) but mechanistic details of the two reactions need clarification. UV/Vis, EPR, and Mössbauer spectroscopies have been used to follow the reactions when apo-EcBfr, pre-loaded anaerobically with Fe2+, was exposed to O2 or H2O2. We show that O2 binds di-Fe2+ FC reversibly, two Fe2+ ions are oxidized in concert and a H2O2 molecule is formed and released to the solution. This peroxide molecule further oxidizes another di-Fe2+ FC, at a rate circa 1000 faster than O2, ensuring an overall 1:4 stoichiometry of iron oxidation by O2. Initially formed Fe3+ can further react with H2O2 (producing protein bound radicals) but relaxes within seconds to an H2O2-unreactive di-Fe3+ form. The data obtained suggest that the primary role of EcBfr in vivo may be to detoxify H2O2 rather than sequester iron.
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Affiliation(s)
- Jacob Pullin
- School of Life SciencesUniversity of EssexWivenhoe ParkColchesterEssexCO4 3SQUK
| | - Michael T. Wilson
- School of Life SciencesUniversity of EssexWivenhoe ParkColchesterEssexCO4 3SQUK
| | - Martin Clémancey
- Université Grenoble AlpesCNRS, CEA, IRIGLaboratoire de Chimie et Biologie des Métaux, UMR 524917 rue des Martyrs38000GrenobleFrance
| | - Geneviève Blondin
- Université Grenoble AlpesCNRS, CEA, IRIGLaboratoire de Chimie et Biologie des Métaux, UMR 524917 rue des Martyrs38000GrenobleFrance
| | - Justin M. Bradley
- School of ChemistryUniversity of East AngliaNorwich Research Park NorwichNorfolkNR4 7TJUK
| | - Geoffrey R. Moore
- School of ChemistryUniversity of East AngliaNorwich Research Park NorwichNorfolkNR4 7TJUK
| | - Nick E. Le Brun
- School of ChemistryUniversity of East AngliaNorwich Research Park NorwichNorfolkNR4 7TJUK
| | - Marina Lučić
- School of Life SciencesUniversity of EssexWivenhoe ParkColchesterEssexCO4 3SQUK
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15
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Pullin J, Wilson MT, Clémancey M, Blondin G, Bradley JM, Moore GR, Le Brun NE, Lučić M, Worrall JAR, Svistunenko DA. Iron Oxidation in Escherichia coli Bacterioferritin Ferroxidase Centre, a Site Designed to React Rapidly with H 2 O 2 but Slowly with O 2. Angew Chem Int Ed Engl 2021; 60:8361-8369. [PMID: 33482043 PMCID: PMC8049013 DOI: 10.1002/anie.202015964] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 01/05/2021] [Indexed: 01/08/2023]
Abstract
Both O2 and H2O2 can oxidize iron at the ferroxidase center (FC) of Escherichia coli bacterioferritin (EcBfr) but mechanistic details of the two reactions need clarification. UV/Vis, EPR, and Mössbauer spectroscopies have been used to follow the reactions when apo‐EcBfr, pre‐loaded anaerobically with Fe2+, was exposed to O2 or H2O2. We show that O2 binds di‐Fe2+ FC reversibly, two Fe2+ ions are oxidized in concert and a H2O2 molecule is formed and released to the solution. This peroxide molecule further oxidizes another di‐Fe2+ FC, at a rate circa 1000 faster than O2, ensuring an overall 1:4 stoichiometry of iron oxidation by O2. Initially formed Fe3+ can further react with H2O2 (producing protein bound radicals) but relaxes within seconds to an H2O2‐unreactive di‐Fe3+ form. The data obtained suggest that the primary role of EcBfr in vivo may be to detoxify H2O2 rather than sequester iron.
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Affiliation(s)
- Jacob Pullin
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester, Essex, CO4 3SQ, UK
| | - Michael T Wilson
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester, Essex, CO4 3SQ, UK
| | - Martin Clémancey
- Université Grenoble Alpes, CNRS, CEA, IRIG, Laboratoire de Chimie et Biologie des Métaux, UMR 5249, 17 rue des Martyrs, 38000, Grenoble, France
| | - Geneviève Blondin
- Université Grenoble Alpes, CNRS, CEA, IRIG, Laboratoire de Chimie et Biologie des Métaux, UMR 5249, 17 rue des Martyrs, 38000, Grenoble, France
| | - Justin M Bradley
- School of Chemistry, University of East Anglia, Norwich Research Park Norwich, Norfolk, NR4 7TJ, UK
| | - Geoffrey R Moore
- School of Chemistry, University of East Anglia, Norwich Research Park Norwich, Norfolk, NR4 7TJ, UK
| | - Nick E Le Brun
- School of Chemistry, University of East Anglia, Norwich Research Park Norwich, Norfolk, NR4 7TJ, UK
| | - Marina Lučić
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester, Essex, CO4 3SQ, UK
| | - Jonathan A R Worrall
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester, Essex, CO4 3SQ, UK
| | - Dimitri A Svistunenko
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester, Essex, CO4 3SQ, UK
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16
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Pullin J, Bradley JM, Moore GR, Le Brun NE, Wilson MT, Svistunenko DA. Electron Transfer from Haem to the Di-Iron Ferroxidase Centre in Bacterioferritin. Angew Chem Weinheim Bergstr Ger 2021; 133:8457-8460. [PMID: 38505322 PMCID: PMC10946800 DOI: 10.1002/ange.202015965] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 01/05/2021] [Indexed: 03/21/2024]
Abstract
The iron redox cycle in ferritins is not completely understood. Bacterioferritins are distinct from other ferritins in that they contain haem groups. It is acknowledged that the two iron motifs in bacterioferritins, the di-nuclear ferroxidase centre and the haem B group, play key roles in two opposing processes, iron sequestration and iron mobilisation, respectively, and the two redox processes are independent. Herein, we show that in Escherichia coli bacterioferritin, there is an electron transfer pathway from the haem to the ferroxidase centre suggesting a new role(s) haem might play in bacterioferritins.
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Affiliation(s)
- Jacob Pullin
- School of Life SciencesUniversity of EssexWivenhoe ParkColchesterEssexCO4 3SQUK
| | - Justin M. Bradley
- School of ChemistryUniversity of East AngliaNorwich Research ParkNorwichNorfolkNR4 7TJUK
| | - Geoffrey R. Moore
- School of ChemistryUniversity of East AngliaNorwich Research ParkNorwichNorfolkNR4 7TJUK
| | - Nick E. Le Brun
- School of ChemistryUniversity of East AngliaNorwich Research ParkNorwichNorfolkNR4 7TJUK
| | - Michael T. Wilson
- School of Life SciencesUniversity of EssexWivenhoe ParkColchesterEssexCO4 3SQUK
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17
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Pullin J, Bradley JM, Moore GR, Le Brun NE, Wilson MT, Svistunenko DA. Electron Transfer from Haem to the Di-Iron Ferroxidase Centre in Bacterioferritin. Angew Chem Int Ed Engl 2021; 60:8376-8379. [PMID: 33460502 PMCID: PMC8048850 DOI: 10.1002/anie.202015965] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 01/05/2021] [Indexed: 12/14/2022]
Abstract
The iron redox cycle in ferritins is not completely understood. Bacterioferritins are distinct from other ferritins in that they contain haem groups. It is acknowledged that the two iron motifs in bacterioferritins, the di‐nuclear ferroxidase centre and the haem B group, play key roles in two opposing processes, iron sequestration and iron mobilisation, respectively, and the two redox processes are independent. Herein, we show that in Escherichia coli bacterioferritin, there is an electron transfer pathway from the haem to the ferroxidase centre suggesting a new role(s) haem might play in bacterioferritins.
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Affiliation(s)
- Jacob Pullin
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester, Essex, CO4 3SQ, UK
| | - Justin M Bradley
- School of Chemistry, University of East Anglia, Norwich Research Park, Norwich, Norfolk, NR4 7TJ, UK
| | - Geoffrey R Moore
- School of Chemistry, University of East Anglia, Norwich Research Park, Norwich, Norfolk, NR4 7TJ, UK
| | - Nick E Le Brun
- School of Chemistry, University of East Anglia, Norwich Research Park, Norwich, Norfolk, NR4 7TJ, UK
| | - Michael T Wilson
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester, Essex, CO4 3SQ, UK
| | - Dimitri A Svistunenko
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester, Essex, CO4 3SQ, UK
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18
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Bradley JM, Svistunenko DA, Wilson MT, Hemmings AM, Moore GR, Le Brun NE. Bacterial iron detoxification at the molecular level. J Biol Chem 2021; 295:17602-17623. [PMID: 33454001 PMCID: PMC7762939 DOI: 10.1074/jbc.rev120.007746] [Citation(s) in RCA: 49] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 10/07/2020] [Indexed: 01/18/2023] Open
Abstract
Iron is an essential micronutrient, and, in the case of bacteria, its availability is commonly a growth-limiting factor. However, correct functioning of cells requires that the labile pool of chelatable "free" iron be tightly regulated. Correct metalation of proteins requiring iron as a cofactor demands that such a readily accessible source of iron exist, but overaccumulation results in an oxidative burden that, if unchecked, would lead to cell death. The toxicity of iron stems from its potential to catalyze formation of reactive oxygen species that, in addition to causing damage to biological molecules, can also lead to the formation of reactive nitrogen species. To avoid iron-mediated oxidative stress, bacteria utilize iron-dependent global regulators to sense the iron status of the cell and regulate the expression of proteins involved in the acquisition, storage, and efflux of iron accordingly. Here, we survey the current understanding of the structure and mechanism of the important members of each of these classes of protein. Diversity in the details of iron homeostasis mechanisms reflect the differing nutritional stresses resulting from the wide variety of ecological niches that bacteria inhabit. However, in this review, we seek to highlight the similarities of iron homeostasis between different bacteria, while acknowledging important variations. In this way, we hope to illustrate how bacteria have evolved common approaches to overcome the dual problems of the insolubility and potential toxicity of iron.
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Affiliation(s)
- Justin M Bradley
- Centre for Molecular and Structural Biochemistry, School of Chemistry, University of East Anglia, Norwich, United Kingdom.
| | | | - Michael T Wilson
- School of Life Sciences, University of Essex, Colchester, United Kingdom
| | - Andrew M Hemmings
- Centre for Molecular and Structural Biochemistry, School of Chemistry, University of East Anglia, Norwich, United Kingdom; Centre for Molecular and Structural Biochemistry, School of Biological Sciences, University of East Anglia, Norwich, United Kingdom
| | - Geoffrey R Moore
- Centre for Molecular and Structural Biochemistry, School of Chemistry, University of East Anglia, Norwich, United Kingdom
| | - Nick E Le Brun
- Centre for Molecular and Structural Biochemistry, School of Chemistry, University of East Anglia, Norwich, United Kingdom.
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19
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Villar I, Larrainzar E, Milazzo L, Pérez-Rontomé C, Rubio MC, Smulevich G, Martínez JI, Wilson MT, Reeder B, Huertas R, Abbruzzetti S, Udvardi M, Becana M. Corrigendum: A Plant Gene Encoding One-Heme and Two-Heme Hemoglobins With Extreme Reactivities Toward Diatomic Gases and Nitrite. Front Plant Sci 2021; 11:637797. [PMID: 33569073 PMCID: PMC7868562 DOI: 10.3389/fpls.2020.637797] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Accepted: 12/22/2020] [Indexed: 06/12/2023]
Abstract
[This corrects the article DOI: 10.3389/fpls.2020.600336.].
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Affiliation(s)
- Irene Villar
- Departamento de Nutrición Vegetal, Estación Experimental de Aula Dei, Consejo Superior de Investigaciones Científicas (CSIC), Zaragoza, Spain
| | - Estíbaliz Larrainzar
- Department of Sciences, Institute for Multidisciplinary Applied Biology, Campus Arrosadía, Universidad Pública de Navarra, Pamplona, Spain
| | - Lisa Milazzo
- Dipartimento di Chimica “Ugo Schiff”, Università di Firenze, Florence, Italy
| | - Carmen Pérez-Rontomé
- Departamento de Nutrición Vegetal, Estación Experimental de Aula Dei, Consejo Superior de Investigaciones Científicas (CSIC), Zaragoza, Spain
| | - Maria C. Rubio
- Departamento de Nutrición Vegetal, Estación Experimental de Aula Dei, Consejo Superior de Investigaciones Científicas (CSIC), Zaragoza, Spain
| | - Giulietta Smulevich
- Dipartimento di Chimica “Ugo Schiff”, Università di Firenze, Florence, Italy
| | - Jesús I. Martínez
- Instituto de Ciencia de Materiales de Aragón, Universidad de Zaragoza-CSIC, Zaragoza, Spain
| | - Michael T. Wilson
- School of Life Sciences, Essex University, Wivenhoe Park, Colchester, United Kingdom
| | - Brandon Reeder
- School of Life Sciences, Essex University, Wivenhoe Park, Colchester, United Kingdom
| | - Raul Huertas
- Noble Research Institute LLC, Ardmore, OK, United States
| | - Stefania Abbruzzetti
- Dipartimento di Scienze Matematiche, Fisiche e Informatiche, Università di Parma, Parma, Italy
| | | | - Manuel Becana
- Departamento de Nutrición Vegetal, Estación Experimental de Aula Dei, Consejo Superior de Investigaciones Científicas (CSIC), Zaragoza, Spain
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20
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Munir A, Wilson MT, Hardwick SW, Chirgadze DY, Worrall JAR, Blundell TL, Chaplin AK. Using cryo-EM to understand antimycobacterial resistance in the catalase-peroxidase (KatG) from Mycobacterium tuberculosis. Structure 2021; 29:899-912.e4. [PMID: 33444527 PMCID: PMC8355310 DOI: 10.1016/j.str.2020.12.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Revised: 11/27/2020] [Accepted: 12/16/2020] [Indexed: 12/12/2022]
Abstract
Resolution advances in cryoelectron microscopy (cryo-EM) now offer the possibility to visualize structural effects of naturally occurring resistance mutations in proteins and also of understanding the binding mechanisms of small drug molecules. In Mycobacterium tuberculosis the multifunctional heme enzyme KatG is indispensable for activation of isoniazid (INH), a first-line pro-drug for treatment of tuberculosis. We present a cryo-EM methodology for structural and functional characterization of KatG and INH resistance variants. The cryo-EM structure of the 161 kDa KatG dimer in the presence of INH is reported to 2.7 Å resolution allowing the observation of potential INH binding sites. In addition, cryo-EM structures of two INH resistance variants, identified from clinical isolates, W107R and T275P, are reported. In combination with electronic absorbance spectroscopy our cryo-EM approach reveals how these resistance variants cause disorder in the heme environment preventing heme uptake and retention, providing insight into INH resistance. A cryo-EM structure to 2.7 Å resolution of M. tuberculosis KatG with isoniazid Cryo-EM is able to visualize multiple dynamic binding modes of isoniazid to KatG Structural disorder in isoniazid resistance mutations is observed Structural disorder of the resistance mutations results in the lack of heme retention
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Affiliation(s)
- Asma Munir
- Department of Biochemistry, University of Cambridge, Cambridge, CB2 1GA, UK
| | - Michael T Wilson
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, UK
| | - Steven W Hardwick
- CryoEM Facility, Department of Biochemistry, University of Cambridge, Cambridge, CB2 1GA, UK
| | - Dimitri Y Chirgadze
- CryoEM Facility, Department of Biochemistry, University of Cambridge, Cambridge, CB2 1GA, UK
| | - Jonathan A R Worrall
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, UK
| | - Tom L Blundell
- Department of Biochemistry, University of Cambridge, Cambridge, CB2 1GA, UK.
| | - Amanda K Chaplin
- Department of Biochemistry, University of Cambridge, Cambridge, CB2 1GA, UK.
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21
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Lučić M, Svistunenko DA, Wilson MT, Chaplin AK, Davy B, Ebrahim A, Axford D, Tosha T, Sugimoto H, Owada S, Dworkowski FSN, Tews I, Owen RL, Hough MA, Worrall JAR. Serial Femtosecond Zero Dose Crystallography Captures a Water-Free Distal Heme Site in a Dye-Decolorising Peroxidase to Reveal a Catalytic Role for an Arginine in Fe IV =O Formation. Angew Chem Int Ed Engl 2020; 59:21656-21662. [PMID: 32780931 PMCID: PMC7756461 DOI: 10.1002/anie.202008622] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Indexed: 01/06/2023]
Abstract
Obtaining structures of intact redox states of metal centers derived from zero dose X-ray crystallography can advance our mechanistic understanding of metalloenzymes. In dye-decolorising heme peroxidases (DyPs), controversy exists regarding the mechanistic role of the distal heme residues aspartate and arginine in the heterolysis of peroxide to form the catalytic intermediate compound I (FeIV =O and a porphyrin cation radical). Using serial femtosecond X-ray crystallography (SFX), we have determined the pristine structures of the FeIII and FeIV =O redox states of a B-type DyP. These structures reveal a water-free distal heme site that, together with the presence of an asparagine, imply the use of the distal arginine as a catalytic base. A combination of mutagenesis and kinetic studies corroborate such a role. Our SFX approach thus provides unique insight into how the distal heme site of DyPs can be tuned to select aspartate or arginine for the rate enhancement of peroxide heterolysis.
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Affiliation(s)
- Marina Lučić
- School of Life SciencesUniversity of EssexWivenhoe ParkColchesterEssexCO4 3SQUK
| | | | - Michael T. Wilson
- School of Life SciencesUniversity of EssexWivenhoe ParkColchesterEssexCO4 3SQUK
| | - Amanda K. Chaplin
- School of Life SciencesUniversity of EssexWivenhoe ParkColchesterEssexCO4 3SQUK
| | - Bradley Davy
- Diamond Light SourceHarwell Science and Innovation CampusDidcotOxfordshireOX11 0DEUK
| | - Ali Ebrahim
- School of Life SciencesUniversity of EssexWivenhoe ParkColchesterEssexCO4 3SQUK
- Diamond Light SourceHarwell Science and Innovation CampusDidcotOxfordshireOX11 0DEUK
| | - Danny Axford
- Diamond Light SourceHarwell Science and Innovation CampusDidcotOxfordshireOX11 0DEUK
| | | | | | - Shigeki Owada
- RIKEN Spring-8 Center1-1-1 KoutoSayoHyogo679-5148Japan
- Japan Synchrotron Radiation Research Institute1-1-1 KoutoSayoHyogo679-5198Japan
| | | | - Ivo Tews
- Biological SciencesInstitute for Life SciencesUniversity of SouthamptonUniversity RoadSouthamptonSO17 1BJUK
| | - Robin L. Owen
- Diamond Light SourceHarwell Science and Innovation CampusDidcotOxfordshireOX11 0DEUK
| | - Michael A. Hough
- School of Life SciencesUniversity of EssexWivenhoe ParkColchesterEssexCO4 3SQUK
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22
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Lučić M, Svistunenko DA, Wilson MT, Chaplin AK, Davy B, Ebrahim A, Axford D, Tosha T, Sugimoto H, Owada S, Dworkowski FSN, Tews I, Owen RL, Hough MA, Worrall JAR. Serial Femtosecond Zero Dose Crystallography Captures a Water‐Free Distal Heme Site in a Dye‐Decolorising Peroxidase to Reveal a Catalytic Role for an Arginine in Fe
IV
=O Formation. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202008622] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Marina Lučić
- School of Life Sciences University of Essex Wivenhoe Park Colchester Essex CO4 3SQ UK
| | | | - Michael T. Wilson
- School of Life Sciences University of Essex Wivenhoe Park Colchester Essex CO4 3SQ UK
| | - Amanda K. Chaplin
- School of Life Sciences University of Essex Wivenhoe Park Colchester Essex CO4 3SQ UK
| | - Bradley Davy
- Diamond Light Source Harwell Science and Innovation Campus Didcot Oxfordshire OX11 0DE UK
| | - Ali Ebrahim
- School of Life Sciences University of Essex Wivenhoe Park Colchester Essex CO4 3SQ UK
- Diamond Light Source Harwell Science and Innovation Campus Didcot Oxfordshire OX11 0DE UK
| | - Danny Axford
- Diamond Light Source Harwell Science and Innovation Campus Didcot Oxfordshire OX11 0DE UK
| | - Takehiko Tosha
- RIKEN Spring-8 Center 1-1-1 Kouto Sayo Hyogo 679-5148 Japan
| | | | - Shigeki Owada
- RIKEN Spring-8 Center 1-1-1 Kouto Sayo Hyogo 679-5148 Japan
- Japan Synchrotron Radiation Research Institute 1-1-1 Kouto Sayo Hyogo 679-5198 Japan
| | | | - Ivo Tews
- Biological Sciences Institute for Life Sciences University of Southampton University Road Southampton SO17 1BJ UK
| | - Robin L. Owen
- Diamond Light Source Harwell Science and Innovation Campus Didcot Oxfordshire OX11 0DE UK
| | - Michael A. Hough
- School of Life Sciences University of Essex Wivenhoe Park Colchester Essex CO4 3SQ UK
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23
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Villar I, Larrainzar E, Milazzo L, Pérez-Rontomé C, Rubio MC, Smulevich G, Martínez JI, Wilson MT, Reeder B, Huertas R, Abbruzzetti S, Udvardi M, Becana M. A Plant Gene Encoding One-Heme and Two-Heme Hemoglobins With Extreme Reactivities Toward Diatomic Gases and Nitrite. Front Plant Sci 2020; 11:600336. [PMID: 33329665 PMCID: PMC7710986 DOI: 10.3389/fpls.2020.600336] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Accepted: 10/16/2020] [Indexed: 05/11/2023]
Abstract
In plants, symbiotic hemoglobins act as carriers and buffers of O2 in nodules, whereas nonsymbiotic hemoglobins or phytoglobins (Glbs) are ubiquitous in tissues and may perform multiple, but still poorly defined, functions related to O2 and/or nitric oxide (NO). Here, we have identified a Glb gene of the model legume Medicago truncatula with unique properties. The gene, designated MtGlb1-2, generates four alternative splice forms encoding Glbs with one or two heme domains and 215-351 amino acid residues. This is more than double the size of any hemoglobin from plants or other organisms described so far. A combination of molecular, cellular, biochemical, and biophysical methods was used to characterize these novel proteins. RNA-sequencing showed that the four splice variants are expressed in plant tissues. MtGlb1-2 is transcriptionally activated by hypoxia and its expression is further enhanced by an NO source. The gene is preferentially expressed in the meristems and vascular bundles of roots and nodules. Two of the proteins, bearing one or two hemes, were characterized using mutants in the distal histidines of the hemes. The Glbs are extremely reactive toward the physiological ligands O2, NO, and nitrite. They show very high O2 affinities, NO dioxygenase activity (in the presence of O2), and nitrite reductase (NiR) activity (in the absence of O2) compared with the hemoglobins from vertebrates and other plants. We propose that these Glbs act as either NO scavengers or NO producers depending on the O2 tension in the plant tissue, being involved in the fast and fine tuning of NO concentration in the cytosol in response to sudden changes in O2 availability.
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Affiliation(s)
- Irene Villar
- Departamento de Nutrición Vegetal, Estación Experimental de Aula Dei, Consejo Superior de Investigaciones Científicas (CSIC), Zaragoza, Spain
| | - Estíbaliz Larrainzar
- Department of Sciences, Institute for Multidisciplinary Applied Biology, Campus Arrosadía, Universidad Pública de Navarra, Pamplona, Spain
| | - Lisa Milazzo
- Dipartimento di Chimica "Ugo Schiff", Università di Firenze, Florence, Italy
| | - Carmen Pérez-Rontomé
- Departamento de Nutrición Vegetal, Estación Experimental de Aula Dei, Consejo Superior de Investigaciones Científicas (CSIC), Zaragoza, Spain
| | - Maria C. Rubio
- Departamento de Nutrición Vegetal, Estación Experimental de Aula Dei, Consejo Superior de Investigaciones Científicas (CSIC), Zaragoza, Spain
| | - Giulietta Smulevich
- Dipartimento di Chimica "Ugo Schiff", Università di Firenze, Florence, Italy
| | - Jesús I. Martínez
- Instituto de Ciencia de Materiales de Aragón, Universidad de Zaragoza-CSIC, Zaragoza, Spain
| | - Michael T. Wilson
- School of Life Sciences, Essex University, Wivenhoe Park, Colchester, United Kingdom
| | - Brandon Reeder
- School of Life Sciences, Essex University, Wivenhoe Park, Colchester, United Kingdom
| | - Raul Huertas
- Noble Research Institute LLC, Ardmore, OK, United States
| | - Stefania Abbruzzetti
- Dipartimento di Scienze Matematiche, Fisiche e Informatiche, Università di Parma, Parma, Italy
| | | | - Manuel Becana
- Departamento de Nutrición Vegetal, Estación Experimental de Aula Dei, Consejo Superior de Investigaciones Científicas (CSIC), Zaragoza, Spain
- *Correspondence: Manuel Becana,
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24
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Lučić M, Chaplin AK, Moreno-Chicano T, Dworkowski FSN, Wilson MT, Svistunenko DA, Hough MA, Worrall JAR. A subtle structural change in the distal haem pocket has a remarkable effect on tuning hydrogen peroxide reactivity in dye decolourising peroxidases fromStreptomyces lividans. Dalton Trans 2020; 49:1620-1636. [DOI: 10.1039/c9dt04583j] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
A subtle positional shift of the distal haem pocket aspartate in two dye decolourising peroxidase homologs has a remarkable effect on their reactivity with H2O2.
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Affiliation(s)
- Marina Lučić
- School of Life Sciences
- University of Essex
- Colchester
- UK
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25
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Straw ML, Hough MA, Wilson MT, Worrall JAR. A Histidine Residue and a Tetranuclear Cuprous-thiolate Cluster Dominate the Copper Loading Landscape of a Copper Storage Protein from Streptomyces lividans. Chemistry 2019; 25:10678-10688. [PMID: 31111982 DOI: 10.1002/chem.201901411] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Revised: 05/10/2019] [Indexed: 01/05/2023]
Abstract
The chemical basis for protecting organisms against the toxic effect imposed by excess cuprous ions is to constrain this through high-affinity binding sites that use cuprous-thiolate coordination chemistry. In bacteria, a family of cysteine rich four-helix bundle proteins utilise thiolate chemistry to bind up to 80 cuprous ions. These proteins have been termed copper storage proteins (Csp). The present study investigates cuprous ion loading to the Csp from Streptomyces lividans (SlCsp) using a combination of X-ray crystallography, site-directed mutagenesis and stopped-flow reaction kinetics with either aquatic cuprous ions or a chelating donor. We illustrate that at low cuprous ion concentrations, copper is loaded exclusively into an outer core region of SlCsp via one end of the four-helix bundle, facilitated by a set of three histidine residues. X-ray crystallography reveals the existence of polynuclear cuprous-thiolate clusters culminating in the assembly of a tetranuclear [Cu4 (μ2 -S-Cys)4 (Νδ1 -His)] cluster in the outer core. As more cuprous ions are loaded, the cysteine lined inner core of SlCsp fills with cuprous ions but in a fluxional and dynamic manner with no evidence for the assembly of further intermediate polynuclear cuprous-thiolate clusters as observed in the outer core. Using site-directed mutagenesis a key role for His107 in the efficient loading of cuprous ions from a donor is established. A model of copper loading to SlCsp is proposed and discussed.
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Affiliation(s)
- Megan L Straw
- School of Biological Sciences, University of Essex, Wivenhoe Park, Colchester, CO4 3SQ, UK
| | - Michael A Hough
- School of Biological Sciences, University of Essex, Wivenhoe Park, Colchester, CO4 3SQ, UK
| | - Michael T Wilson
- School of Biological Sciences, University of Essex, Wivenhoe Park, Colchester, CO4 3SQ, UK
| | - Jonathan A R Worrall
- School of Biological Sciences, University of Essex, Wivenhoe Park, Colchester, CO4 3SQ, UK
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26
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Chaplin AK, Chicano TM, Hampshire BV, Wilson MT, Hough MA, Svistunenko DA, Worrall JAR. An Aromatic Dyad Motif in Dye Decolourising Peroxidases Has Implications for Free Radical Formation and Catalysis. Chemistry 2019; 25:6141-6153. [PMID: 30945782 DOI: 10.1002/chem.201806290] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Indexed: 01/27/2023]
Abstract
Dye decolouring peroxidases (DyPs) are the most recent class of heme peroxidase to be discovered. On reacting with H2 O2 , DyPs form a high-valent iron(IV)-oxo species and a porphyrin radical (Compound I) followed by stepwise oxidation of an organic substrate. In the absence of substrate, the ferryl species decays to form transient protein-bound radicals on redox active amino acids. Identification of radical sites in DyPs has implications for their oxidative mechanism with substrate. Using a DyP from Streptomyces lividans, referred to as DtpA, which displays low reactivity towards synthetic dyes, activation with H2 O2 was explored. A Compound I EPR spectrum was detected, which in the absence of substrate decays to a protein-bound radical EPR signal. Using a newly developed version of the Tyrosyl Radical Spectra Simulation Algorithm, the radical EPR signal was shown to arise from a pristine tyrosyl radical and not a mixed Trp/Tyr radical that has been widely reported in DyP members exhibiting high activity with synthetic dyes. The radical site was identified as Tyr374, with kinetic studies inferring that although Tyr374 is not on the electron-transfer pathway from the dye RB19, its replacement with a Phe does severely compromise activity with other organic substrates. These findings hint at the possibility that alternative electron-transfer pathways for substrate oxidation are operative within the DyP family. In this context, a role for a highly conserved aromatic dyad motif is discussed.
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Affiliation(s)
- Amanda K Chaplin
- Present address: Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge, CB2 1GA, UK
| | - Tadeo Moreno Chicano
- Present address: Department of Molecular Mechanisms, Max Planck Institute for Medical Research, Jahnstraße 29, 69120, Heidelberg, Germany
| | - Bethany V Hampshire
- Present address: Department of Physics, University of Warwick, Coventry, CV4 7AL, UK
| | - Michael T Wilson
- School of Biological Sciences, University of Essex, Wivenhoe Park, Colchester, CO4 3SQ, UK
| | - Michael A Hough
- School of Biological Sciences, University of Essex, Wivenhoe Park, Colchester, CO4 3SQ, UK
| | - Dimitri A Svistunenko
- School of Biological Sciences, University of Essex, Wivenhoe Park, Colchester, CO4 3SQ, UK
| | - Jonathan A R Worrall
- School of Biological Sciences, University of Essex, Wivenhoe Park, Colchester, CO4 3SQ, UK
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27
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Abstract
Three EPR signals from individual free radical species have been identified in the EPR spectra of horse heart metmyoglobin (HH metMb) mixed with hydrogen peroxide (H2O2). The peroxyl radical EPR signal was assigned to the Trp14-OO• radical, the seven component signal – to the Tyr103• radical and the singlet EPR signal was assigned to the Tyr146• radical. Apo-Mb (haem free HH Mb) added in various concentrations to the native metMb prior to H2O2 addition affected the yields of the three types of radicals. As the concentrations of metMb and H2O2 were kept constant, the yield of the primary radical formed is the same in all experiments, H2O2 being unable to produce any radical in the reaction with a haem free protein. Nevertheless, the addition of apo-Mb resulted in an increase of the Tyr146• radical concentration and in a quantitatively similar decrease of the Tyr103• radical concentration. These changes were dependent on the concentration of the added apo-Mb. Thus we show that a radical transfer Tyr103• → Tyr146• occurs and that this reaction is protein concentration dependent. The question whether this radical transfer is inter- or intra-molecular is discussed. A similarity is drawn between the system studied and the sperm whale metMb/H2O2 system, for which the radical transfer Tyr103• → Tyr151• has been previously suggested.
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Affiliation(s)
- Dimitri A. Svistunenko
- Department of Biological Sciences, Central Campus, University of Essex, Wivenhoe Park, Colchester, Essex CO4 3SQ, UK
| | - Brandon J. Reeder
- Department of Biological Sciences, Central Campus, University of Essex, Wivenhoe Park, Colchester, Essex CO4 3SQ, UK
| | - Michael T. Wilson
- Department of Biological Sciences, Central Campus, University of Essex, Wivenhoe Park, Colchester, Essex CO4 3SQ, UK
| | - Chris E. Cooper
- Department of Biological Sciences, Central Campus, University of Essex, Wivenhoe Park, Colchester, Essex CO4 3SQ, UK
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28
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Straw ML, Chaplin AK, Hough MA, Paps J, Bavro VN, Wilson MT, Vijgenboom E, Worrall JAR. A cytosolic copper storage protein provides a second level of copper tolerance in Streptomyces lividans. Metallomics 2019; 10:180-193. [PMID: 29292456 DOI: 10.1039/c7mt00299h] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Streptomyces lividans has a distinct dependence on the bioavailability of copper for its morphological development. A cytosolic copper resistance system is operative in S. lividans that serves to preclude deleterious copper levels. This system comprises of several CopZ-like copper chaperones and P1-type ATPases, predominantly under the transcriptional control of a metalloregulator from the copper sensitive operon repressor (CsoR) family. In the present study, we discover a new layer of cytosolic copper resistance in S. lividans that involves a protein belonging to the newly discovered family of copper storage proteins, which we have named Ccsp (cytosolic copper storage protein). From an evolutionary perspective, we find Ccsp homologues to be widespread in Bacteria and extend through into Archaea and Eukaryota. Under copper stress Ccsp is upregulated and consists of a homotetramer assembly capable of binding up to 80 cuprous ions (20 per protomer). X-ray crystallography reveals 18 cysteines, 3 histidines and 1 aspartate are involved in cuprous ion coordination. Loading of cuprous ions to Ccsp is a cooperative process with a Hill coefficient of 1.9 and a CopZ-like copper chaperone can transfer copper to Ccsp. A Δccsp mutant strain indicates that Ccsp is not required under initial copper stress in S. lividans, but as the CsoR/CopZ/ATPase efflux system becomes saturated, Ccsp facilitates a second level of copper tolerance.
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Affiliation(s)
- Megan L Straw
- School of Biological Sciences, University of Essex, Wivenhoe Park, Colchester, CO4 3SQ, UK.
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29
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Deacon OM, Svistunenko DA, Moore GR, Wilson MT, Worrall JA. Naturally Occurring Disease-Related Mutations in the 40–57 Ω-Loop of Human Cytochrome c Control Triggering of the Alkaline Isomerization. Biochemistry 2018; 57:4276-4288. [DOI: 10.1021/acs.biochem.8b00520] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Oliver M. Deacon
- School of Biological Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, U.K
| | - Dimitri A. Svistunenko
- School of Biological Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, U.K
| | - Geoffrey R. Moore
- School of Chemistry, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, U.K
| | - Michael T. Wilson
- School of Biological Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, U.K
| | - Jonathan A.R. Worrall
- School of Biological Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, U.K
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30
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Wilson MT, Tang AD, Iyer K, McKee H, Waas J, Rodger J. The challenges of producing effective small coils for transcranial magnetic stimulation of mice. Biomed Phys Eng Express 2018. [DOI: 10.1088/2057-1976/aab525] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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31
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Deacon OM, Karsisiotis AI, Moreno-Chicano T, Hough MA, Macdonald C, Blumenschein TMA, Wilson MT, Moore GR, Worrall JAR. Heightened Dynamics of the Oxidized Y48H Variant of Human Cytochrome c Increases Its Peroxidatic Activity. Biochemistry 2017; 56:6111-6124. [PMID: 29083920 DOI: 10.1021/acs.biochem.7b00890] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Proteins performing multiple biochemical functions are called "moonlighting proteins" or extreme multifunctional (EMF) proteins. Mitochondrial cytochrome c is an EMF protein that binds multiple partner proteins to act as a signaling molecule, transfers electrons in the respiratory chain, and acts as a peroxidase in apoptosis. Mutations in the cytochrome c gene lead to the disease thrombocytopenia, which is accompanied by enhanced apoptotic activity. The Y48H variant arises from one such mutation and is found in the 40-57 Ω-loop, the lowest-unfolding free energy substructure of the cytochrome c fold. A 1.36 Å resolution X-ray structure of the Y48H variant reveals minimal structural changes compared to the wild-type structure, with the axial Met80 ligand coordinated to the heme iron. Despite this, the intrinsic peroxidase activity is enhanced, implying that a pentacoordinate heme state is more prevalent in the Y48H variant, corroborated through determination of a Met80 "off rate" of >125 s-1 compared to a rate of ∼6 s-1 for the wild-type protein. Heteronuclear nuclear magnetic resonance measurements with the oxidized Y48H variant reveal heightened dynamics in the 40-57 Ω-loop and the Met80-containing 71-85 Ω-loop relative to the wild-type protein, illustrating communication between these substructures. Placed into context with the G41S cytochrome c variant, also implicated in thrombocytopenia, a dynamic picture associated with this disease relative to cytochrome c is emerging whereby increasing dynamics in substructures of the cytochrome c fold serve to facilitate an increased population of the peroxidatic pentacoordinate heme state in the following order: wild type < G41S < Y48H.
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Affiliation(s)
- Oliver M Deacon
- School of Biological Sciences, University of Essex , Wivenhoe Park, Colchester CO4 3SQ, U.K
| | | | - Tadeo Moreno-Chicano
- School of Biological Sciences, University of Essex , Wivenhoe Park, Colchester CO4 3SQ, U.K
| | - Michael A Hough
- School of Biological Sciences, University of Essex , Wivenhoe Park, Colchester CO4 3SQ, U.K
| | - Colin Macdonald
- School of Chemistry, University of East Anglia , Norwich Research Park, Norwich NR4 7TJ, U.K
| | - Tharin M A Blumenschein
- School of Chemistry, University of East Anglia , Norwich Research Park, Norwich NR4 7TJ, U.K
| | - Michael T Wilson
- School of Biological Sciences, University of Essex , Wivenhoe Park, Colchester CO4 3SQ, U.K
| | - Geoffrey R Moore
- School of Chemistry, University of East Anglia , Norwich Research Park, Norwich NR4 7TJ, U.K
| | - Jonathan A R Worrall
- School of Biological Sciences, University of Essex , Wivenhoe Park, Colchester CO4 3SQ, U.K
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32
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Kekilli D, Petersen CA, Pixton DA, Ghafoor DD, Abdullah GH, Dworkowski FSN, Wilson MT, Heyes DJ, Hardman SJO, Murphy LM, Strange RW, Scrutton NS, Andrew CR, Hough MA. Engineering proximal vs. distal heme-NO coordination via dinitrosyl dynamics: implications for NO sensor design. Chem Sci 2017; 8:1986-1994. [PMID: 28451315 PMCID: PMC5390784 DOI: 10.1039/c6sc04190f] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2016] [Accepted: 11/08/2016] [Indexed: 01/18/2023] Open
Abstract
Proximal vs. distal heme-NO coordination is a novel strategy for selective gas response in heme-based NO-sensors. In the case of Alcaligenes xylosoxidans cytochrome c' (AXCP), formation of a transient distal 6cNO complex is followed by scission of the trans Fe-His bond and conversion to a proximal 5cNO product via a putative dinitrosyl species. Here we show that replacement of the AXCP distal Leu16 residue with smaller or similar sized residues (Ala, Val or Ile) traps the distal 6cNO complex, whereas Leu or Phe residues lead to a proximal 5cNO product with a transient or non-detectable distal 6cNO precursor. Crystallographic, spectroscopic, and kinetic measurements of 6cNO AXCP complexes show that increased distal steric hindrance leads to distortion of the Fe-N-O angle and flipping of the heme 7-propionate. However, it is the kinetic parameters of the distal NO ligand that determine whether 6cNO or proximal 5cNO end products are formed. Our data support a 'balance of affinities' mechanism in which proximal 5cNO coordination depends on relatively rapid release of the distal NO from the dinitrosyl precursor. This mechanism, which is applicable to other proteins that form transient dinitrosyls, represents a novel strategy for 5cNO formation that does not rely on an inherently weak Fe-His bond. Our data suggest a general means of engineering selective gas response into biologically-derived gas sensors in synthetic biology.
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Affiliation(s)
- Demet Kekilli
- School of Biological Sciences , University of Essex , Wivenhoe Park , Colchester , Essex CO4 3SQ , UK .
| | - Christine A Petersen
- Department of Chemistry and Biochemistry , Eastern Oregon University , La Grande , Oregon 97850 , USA .
| | - David A Pixton
- Department of Chemistry and Biochemistry , Eastern Oregon University , La Grande , Oregon 97850 , USA .
| | - Dlzar D Ghafoor
- Faculty of Science and Education Science , University of Sulaimani , Sulaymaniyah , Iraq
| | | | | | - Michael T Wilson
- School of Biological Sciences , University of Essex , Wivenhoe Park , Colchester , Essex CO4 3SQ , UK .
| | - Derren J Heyes
- Manchester Institute of Biotechnology , 131 Princess Street , Manchester M1 7DN , UK
| | - Samantha J O Hardman
- Manchester Institute of Biotechnology , 131 Princess Street , Manchester M1 7DN , UK
| | - Loretta M Murphy
- School of Chemistry , Bangor University , Bangor , Gwynedd , Wales LL57 2UW , UK
| | - Richard W Strange
- School of Biological Sciences , University of Essex , Wivenhoe Park , Colchester , Essex CO4 3SQ , UK .
- Molecular Biophysics Group , Institute of Integrative Biology , Faculty of Health and Life Sciences , University of Liverpool , Liverpool , L69 7ZB , UK
| | - Nigel S Scrutton
- Manchester Institute of Biotechnology , 131 Princess Street , Manchester M1 7DN , UK
| | - Colin R Andrew
- Department of Chemistry and Biochemistry , Eastern Oregon University , La Grande , Oregon 97850 , USA .
| | - Michael A Hough
- School of Biological Sciences , University of Essex , Wivenhoe Park , Colchester , Essex CO4 3SQ , UK .
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33
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Welbourn EM, Wilson MT, Yusof A, Metodiev MV, Cooper CE. The mechanism of formation, structure and physiological relevance of covalent hemoglobin attachment to the erythrocyte membrane. Free Radic Biol Med 2017; 103:95-106. [PMID: 28007575 PMCID: PMC5282401 DOI: 10.1016/j.freeradbiomed.2016.12.024] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Revised: 12/14/2016] [Accepted: 12/18/2016] [Indexed: 12/20/2022]
Abstract
Covalent hemoglobin binding to membranes leads to band 3 (AE1) clustering and the removal of erythrocytes from the circulation; it is also implicated in blood storage lesions. Damaged hemoglobin, with the heme being in a redox and oxygen-binding inactive hemichrome form, has been implicated as the binding species. However, previous studies used strong non-physiological oxidants. In vivo hemoglobin is constantly being oxidised to methemoglobin (ferric), with around 1% of hemoglobin being in this form at any one time. In this study we tested the ability of the natural oxidised form of hemoglobin (methemoglobin) in the presence or absence of the physiological oxidant hydrogen peroxide to initiate membrane binding. The higher the oxidation state of hemoglobin (from Fe(III) to Fe(V)) the more binding was observed, with approximately 50% of this binding requiring reactive sulphydryl groups. The hemoglobin bound was in a high molecular weight complex containing spectrin, ankyrin and band 4.2, which are common to one of the cytoskeletal nodes. Unusually, we showed that hemoglobin bound in this way was redox active and capable of ligand binding. It can initiate lipid peroxidation showing the potential to cause cell damage. In vivo oxidative stress studies using extreme endurance exercise challenges showed an increase in hemoglobin membrane binding, especially in older cells with lower levels of antioxidant enzymes. These are then targeted for destruction. We propose a model where mild oxidative stress initiates the binding of redox active hemoglobin to the membrane. The maximum lifetime of the erythrocyte is thus governed by the redox activity of the cell; from the moment of its release into the circulation the timer is set.
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Affiliation(s)
| | - Michael T Wilson
- School of Biological Sciences, University of Essex, Colchester CO4 3SQ, UK
| | - Ashril Yusof
- Dept. of Exercise Science, Sports Centre, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Metodi V Metodiev
- School of Biological Sciences, University of Essex, Colchester CO4 3SQ, UK
| | - Chris E Cooper
- School of Biological Sciences, University of Essex, Colchester CO4 3SQ, UK.
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Ioannis Karsisiotis A, Deacon OM, Wilson MT, Macdonald C, Blumenschein TM, Moore GR, Worrall JA. The G41S Variant of Human Cytochrome C Enhances Apoptosis via Increased Dynamics. Biophys J 2017. [DOI: 10.1016/j.bpj.2016.11.210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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Chaplin AK, Wilson MT, Worrall JAR. Kinetic characterisation of a dye decolourising peroxidase from Streptomyces lividans: new insight into the mechanism of anthraquinone dye decolourisation. Dalton Trans 2017; 46:9420-9429. [DOI: 10.1039/c7dt01144j] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A dye decolourising haem peroxidase fromStreptomyces lividansdecolourises the anthraquinone dye RB19 through a disproportionation mechanism.
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Karsisiotis AI, Deacon OM, Wilson MT, Macdonald C, Blumenschein TMA, Moore GR, Worrall JAR. Increased dynamics in the 40-57 Ω-loop of the G41S variant of human cytochrome c promote its pro-apoptotic conformation. Sci Rep 2016; 6:30447. [PMID: 27461282 PMCID: PMC4962053 DOI: 10.1038/srep30447] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Accepted: 07/05/2016] [Indexed: 12/26/2022] Open
Abstract
Thrombocytopenia 4 is an inherited autosomal dominant thrombocytopenia, which occurs due to mutations in the human gene for cytochrome c that results in enhanced mitochondrial apoptotic activity. The Gly41Ser mutation was the first to be reported. Here we report stopped-flow kinetic studies of azide binding to human ferricytochrome c and its Gly41Ser variant, together with backbone amide H/D exchange and 15N-relaxation dynamics using NMR spectroscopy, to show that alternative conformations are kinetically and thermodynamically more readily accessible for the Gly41Ser variant than for the wild-type protein. Our work reveals a direct conformational link between the 40–57 Ω-loop in which residue 41 resides and the dynamical properties of the axial ligand to the heme iron, Met80, such that the replacement of glycine by serine promotes the dissociation of the Met80 ligand, thereby increasing the population of a peroxidase active state, which is a key non-native conformational state in apoptosis.
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Affiliation(s)
| | - Oliver M Deacon
- School of Biological Sciences, University of Essex, Wivenhoe Park, Colchester, CO4 3SQ, UK
| | - Michael T Wilson
- School of Biological Sciences, University of Essex, Wivenhoe Park, Colchester, CO4 3SQ, UK
| | - Colin Macdonald
- School of Chemistry, University of East Anglia, Norwich Research Park, NR4 7TJ, UK
| | | | - Geoffrey R Moore
- School of Chemistry, University of East Anglia, Norwich Research Park, NR4 7TJ, UK
| | - Jonathan A R Worrall
- School of Biological Sciences, University of Essex, Wivenhoe Park, Colchester, CO4 3SQ, UK
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Chaplin AK, Wilson MT, Hough MA, Svistunenko DA, Hemsworth GR, Walton PH, Vijgenboom E, Worrall JAR. Heterogeneity in the Histidine-brace Copper Coordination Sphere in Auxiliary Activity Family 10 (AA10) Lytic Polysaccharide Monooxygenases. J Biol Chem 2016; 291:12838-12850. [PMID: 27129229 DOI: 10.1074/jbc.m116.722447] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Indexed: 12/23/2022] Open
Abstract
Copper-dependent lytic polysaccharide monooxygenases (LPMOs) are enzymes that oxidatively deconstruct polysaccharides. The active site copper in LPMOs is coordinated by a histidine-brace. This utilizes the amino group and side chain of the N-terminal His residue with the side chain of a second His residue to create a T-shaped arrangement of nitrogen ligands. We report a structural, kinetic, and thermodynamic appraisal of copper binding to the histidine-brace in an auxiliary activity family 10 (AA10) LPMO from Streptomyces lividans (SliLPMO10E). Unexpectedly, we discovered the existence of two apo-SliLPMO10E species in solution that can each bind copper at a single site with distinct kinetic and thermodynamic (exothermic and endothermic) properties. The experimental EPR spectrum of copper-bound SliLPMO10E requires the simulation of two different line shapes, implying two different copper-bound species, indicative of three and two nitrogen ligands coordinating the copper. Amino group coordination was probed through the creation of an N-terminal extension variant (SliLPMO10E-Ext). The kinetics and thermodynamics of copper binding to SliLPMO10E-Ext are in accord with copper binding to one of the apo-forms in the wild-type protein, suggesting that amino group coordination is absent in the two-nitrogen coordinate form of SliLPMO10E. Copper binding to SliLPMO10B was also investigated, and again it revealed the presence of two apo-forms with kinetics and stoichiometry of copper binding identical to that of SliLPMO10E. Our findings highlight that heterogeneity exists in the active site copper coordination sphere of LPMOs that may have implications for the mechanism of loading copper in the cell.
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Affiliation(s)
- Amanda K Chaplin
- From the School of Biological Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, United Kingdom
| | - Michael T Wilson
- From the School of Biological Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, United Kingdom
| | - Michael A Hough
- From the School of Biological Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, United Kingdom
| | - Dimitri A Svistunenko
- From the School of Biological Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, United Kingdom
| | - Glyn R Hemsworth
- the Department of Chemistry, University of York, Heslington, York YO10 5DD, United Kingdom, and
| | - Paul H Walton
- the Department of Chemistry, University of York, Heslington, York YO10 5DD, United Kingdom, and
| | - Erik Vijgenboom
- the Molecular Biotechnology, Institute of Biology, Sylvius Laboratory, Leiden University, P. O. Box 9505, 2300RA Leiden, The Netherlands
| | - Jonathan A R Worrall
- From the School of Biological Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, United Kingdom,.
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Silkstone G, Wilson MT. A Further Investigation of the Effects of Extremely Low Frequency Magnetic Fields on Alkaline Phosphatase and Acetylcholinesterase. PLoS One 2016; 11:e0148369. [PMID: 26963611 PMCID: PMC4786325 DOI: 10.1371/journal.pone.0148369] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Accepted: 01/18/2016] [Indexed: 11/19/2022] Open
Abstract
Using a custom build spectrophotometer equipped with Helmholtz coils and designed to study the effects of magnetic fields on enzyme reactions in real-time we have investigated the influence of fields, from 100 μT to 10 mT and at a variety of field frequencies, on the membrane bound enzymes alkaline phosphatase and acetylcholinesterase. We have also employed other methods to apply a magnetic field, e.g. Biostim. In contrast to earlier reports we have been unable to detect any field effects on these enzymes under any field/frequency regime. We discuss possible reasons for the discrepancy between this and earlier work and note the particularly complex influence of small temperature changes that may confound analysis.
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Affiliation(s)
- Gary Silkstone
- School of Biology, University of Essex, Wivenhoe Park, Colchester, Essex, CO4 3SQ, United Kingdom
| | - Michael T. Wilson
- School of Biology, University of Essex, Wivenhoe Park, Colchester, Essex, CO4 3SQ, United Kingdom
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Abstract
The intricate interplay between polypeptide and metal ion binding underscores many of life's fundamental processes. Metalloregulators recognise and bind cognate metal ions during cellular metal stress, evoking a transcriptional response so as to maintain metal ion homeostasis. Members of the copper sensitive operon repressor (CsoR) family of metalloregulators bind to their operator DNA in the absence of a bound metal ion, but on binding Cu(I) an allosteric conformational switch is induced that causes dissociation of the bound DNA. Other divalent metal ions are capable of binding to CsoR members but do not induce the allosteric response observed with Cu(I). The thermodynamics of Cu(I) binding has been studied in this family of metalloregulators, but the binding kinetics and mechanism of Cu(I) or a non-cognate metal ion is unknown. In the present study we have used stopped-flow absorbance kinetics and site-directed variants of the CsoR from Streptomyces lividans to monitor binding of Cu(I) and non-cognate Ni(II). The variants have been designed to individually replace known metal ion binding ligands and also to test the role of a histidine residue (His103) close, but not considered part of the Cu(I) first coordination sphere. Cu(I)/Ni(II) ion displacement studies have also been investigated. The kinetic data are most consistent with the existence of two distinct mechanisms that account for Cu(I) and Ni(II) ion binding to this CsoR. In particular Ni(II) has two binding sites; one that has identical amino acid coordination as the Cu(I) binding site and the second involving His103, a residue determined here not to be involved in the mechanism of Cu(I) binding.
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Affiliation(s)
- Tatiana V Porto
- School of Biological Sciences, University of Essex, Wivenhoe Park, Colchester, CO4 3SQ, UK.
| | - Michael T Wilson
- School of Biological Sciences, University of Essex, Wivenhoe Park, Colchester, CO4 3SQ, UK.
| | - Jonathan A R Worrall
- School of Biological Sciences, University of Essex, Wivenhoe Park, Colchester, CO4 3SQ, UK.
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van Wilderen LJGW, Silkstone G, Mason M, van Thor JJ, Wilson MT. Kinetic studies on the oxidation of semiquinone and hydroquinone forms of Arabidopsis cryptochrome by molecular oxygen. FEBS Open Bio 2015; 5:885-92. [PMID: 26649273 PMCID: PMC4643184 DOI: 10.1016/j.fob.2015.10.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Revised: 10/18/2015] [Accepted: 10/20/2015] [Indexed: 11/29/2022] Open
Abstract
The flavin chromophore of the photoreceptor cryptochrome is reduced by light. The neutral flavin semiquinone is accumulated under anaerobic conditions. Fully-reduced flavin forms in presence of external reductant (anaerobic conditions). Stopped-flow experiments reveal light-independent recovery of the ground state. The dark recovery process requires molecular oxygen.
Cryptochromes (crys) are flavoprotein photoreceptors present throughout the biological kingdom that play important roles in plant development and entrainment of the circadian clock in several organisms. Crys non-covalently bind flavin adenine dinucleotide (FAD) which undergoes photoreduction from the oxidised state to a radical form suggested to be active in signalling in vivo. Although the photoreduction reactions have been well characterised by a number of approaches, little is known of the oxidation reactions of crys and their mechanisms. In this work, a stopped-flow kinetics approach is used to investigate the mechanism of cry oxidation in the presence and absence of an external electron donor. This in vitro study extends earlier investigations of the oxidation of Arabidopsis cryptochrome1 by molecular oxygen and demonstrates that, under some conditions, a more complex model for oxidation of the flavin than was previously proposed is required to accommodate the spectral evidence (see P. Müller and M. Ahmad (2011) J. Biol. Chem. 286, 21033–21040 [1]). In the absence of an electron donor, photoreduction leads predominantly to the formation of the radical FADH•. Dark recovery most likely forms flavin hydroperoxide (FADHOOH) requiring superoxide. In the presence of reductant (DTT), illumination yields the fully reduced flavin species (FADH−). Reaction of this with dioxygen leads to transient radical (FADH•) and simultaneous accumulation of oxidised species (FAD), possibly governed by interplay between different cryptochrome molecules or cooperativity effects within the cry homodimer.
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Affiliation(s)
- Luuk J G W van Wilderen
- Division of Molecular Biosciences, Faculty of Natural Sciences, South Kensington Campus, Imperial College London, London, United Kingdom
| | - Gary Silkstone
- Department of Biological Sciences, University of Essex, Wivenhoe Park, Colchester, United Kingdom
| | - Maria Mason
- Department of Biological Sciences, University of Essex, Wivenhoe Park, Colchester, United Kingdom
| | - Jasper J van Thor
- Division of Molecular Biosciences, Faculty of Natural Sciences, South Kensington Campus, Imperial College London, London, United Kingdom
| | - Michael T Wilson
- Department of Biological Sciences, University of Essex, Wivenhoe Park, Colchester, United Kingdom
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Kassa T, Jana S, Strader MB, Meng F, Jia Y, Wilson MT, Alayash AI. Sickle Cell Hemoglobin in the Ferryl State Promotes βCys-93 Oxidation and Mitochondrial Dysfunction in Epithelial Lung Cells (E10). J Biol Chem 2015; 290:27939-58. [PMID: 26396189 DOI: 10.1074/jbc.m115.651257] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Indexed: 01/02/2023] Open
Abstract
Polymerization of intraerythrocytic deoxyhemoglobin S (HbS) is the primary molecular event that leads to hemolytic anemia in sickle cell disease (SCD). We reasoned that HbS may contribute to the complex pathophysiology of SCD in part due to its pseudoperoxidase activity. We compared oxidation reactions and the turnover of oxidation intermediates of purified human HbS and HbA. Hydrogen peroxide (H2O2) drives a catalytic cycle that includes the following three distinct steps: 1) initial oxidation of ferrous (oxy) to ferryl Hb; 2) autoreduction of the ferryl intermediate to ferric (metHb); and 3) reaction of metHb with an additional H2O2 molecule to regenerate the ferryl intermediate. Ferrous and ferric forms of both proteins underwent initial oxidation to the ferryl heme in the presence of H2O2 at equal rates. However, the rate of autoreduction of ferryl to the ferric form was slower in the HbS solutions. Using quantitative mass spectrometry and the spin trap, 5,5-dimethyl-1-pyrroline-N-oxide, we found more irreversibly oxidized βCys-93in HbS than in HbA. Incubation of the ferric or ferryl HbS with cultured lung epithelial cells (E10) induced a drop in mitochondrial oxygen consumption rate and impairment of cellular bioenergetics that was related to the redox state of the iron. Ferryl HbS induced a substantial drop in the mitochondrial transmembrane potential and increases in cytosolic heme oxygenase (HO-1) expression and mitochondrial colocalization in E10 cells. Thus, highly oxidizing ferryl Hb and heme, the product of oxidation, may be central to the evolution of vasculopathy in SCD and may suggest therapeutic modalities that interrupt heme-mediated inflammation.
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Affiliation(s)
- Tigist Kassa
- From the Laboratory of Biochemistry and Vascular Biology, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland 20993 and
| | - Sirsendu Jana
- From the Laboratory of Biochemistry and Vascular Biology, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland 20993 and
| | - Michael Brad Strader
- From the Laboratory of Biochemistry and Vascular Biology, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland 20993 and
| | - Fantao Meng
- From the Laboratory of Biochemistry and Vascular Biology, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland 20993 and
| | - Yiping Jia
- From the Laboratory of Biochemistry and Vascular Biology, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland 20993 and
| | - Michael T Wilson
- the Department of Biological Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, United Kingdom
| | - Abdu I Alayash
- From the Laboratory of Biochemistry and Vascular Biology, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland 20993 and
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42
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Ghafoor DD, Kekilli D, Abdullah GH, Dworkowski FSN, Hassan HG, Wilson MT, Strange RW, Hough MA. Hydrogen bonding of the dissociated histidine ligand is not required for formation of a proximal NO adduct in cytochrome c'. J Biol Inorg Chem 2015; 20:949-56. [PMID: 26100643 DOI: 10.1007/s00775-015-1278-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2015] [Accepted: 06/04/2015] [Indexed: 11/28/2022]
Abstract
Cytochromes c', that occur in methanotrophic, denitrifying and photosynthetic bacteria, form unusual proximal penta-coordinate NO complexes via a hexa-coordinate distal NO intermediate. Their NO binding properties are similar to those of the eukaryotic NO sensor, soluble guanylate cyclase, for which they provide a valuable structural model. Previous studies suggested that hydrogen bonding between the displaced proximal histidine (His120) ligand (following its dissociation from heme due to trans effects from the distally bound NO) and a conserved aspartate residue (Asp121) could play a key role in allowing proximal NO binding to occur. We have characterized three variants of Alcaligenes xylosoxidans cytochrome c' (AXCP) where Asp121 has been replaced by Ala, Ile and Gln, respectively. In all variants, hydrogen bonding between residue 121 and His120 is abolished yet 5-coordinate proximal NO species are still formed. Our data therefore demonstrate that the His120-Asp121 bond is not essential for proximal NO binding although it likely provides an energy minimum for the displaced His ligand. All variants have altered proximal pocket structure relative to native AXCP.
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Affiliation(s)
- Dlzar D Ghafoor
- Faculty of Science and Education Science, University of Sulaimani, Sulaymaniyah, Iraq
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Ascenzi P, Coletta M, Wilson MT, Fiorucci L, Marino M, Polticelli F, Sinibaldi F, Santucci R. Cardiolipin-cytochrome c complex: Switching cytochrome c from an electron-transfer shuttle to a myoglobin- and a peroxidase-like heme-protein. IUBMB Life 2015; 67:98-109. [PMID: 25857294 DOI: 10.1002/iub.1350] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Accepted: 01/11/2015] [Indexed: 12/18/2022]
Abstract
Cytochrome c (cytc) is a small heme-protein located in the space between the inner and the outer membrane of the mitochondrion that transfers electrons from cytc-reductase to cytc-oxidase. The hexa-coordinated heme-Fe atom of cytc displays a very low reactivity toward ligands and does not exhibit significant catalytic properties. However, upon cardiolipin (CL) binding, cytc achieves ligand binding and catalytic properties reminiscent of those of myoglobin and peroxidase. In particular, the peroxidase activity of the cardiolipin-cytochrome c complex (CL-cytc) is critical for the redistribution of CL from the inner to the outer mitochondrial membranes and is essential for the execution and completion of the apoptotic program. On the other hand, the capability of CL-cytc to bind NO and CO and the heme-Fe-based scavenging of reactive nitrogen and oxygen species may affect apoptosis. Here, the ligand binding and catalytic properties of CL-cytc are analyzed in parallel with those of CL-free cytc, myoglobin, and peroxidase to dissect the potential mechanisms of CL in modulating the pro- and anti-apoptotic actions of cytc.
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Affiliation(s)
- Paolo Ascenzi
- Interdepartmental Laboratory for Electron Microscopy, Roma Tre University, Roma, Italy
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44
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Beckerson P, Reeder BJ, Wilson MT. Coupling of disulfide bond and distal histidine dissociation in human ferrous cytoglobin regulates ligand binding. FEBS Lett 2015; 589:507-12. [DOI: 10.1016/j.febslet.2015.01.010] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Revised: 01/08/2015] [Accepted: 01/10/2015] [Indexed: 10/24/2022]
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Abstract
There has been great interest in unraveling the complex inter-relationships between microbes and humans as they relate to human health and disease. This review will focus on recent advances in the appreciation and understanding of these relationships in terms of the upper respiratory tract, specifically the nose and paranasal sinuses.
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Affiliation(s)
- Michael T Wilson
- The Division of Rheumatology, Allergy and Immunology, Massachusetts General Hospital, 55 Fruit Street, Cox 2-201, Boston, MA, 02114, USA
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46
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Ye CJ, Feng T, Kwon HK, Raj T, Wilson MT, Asinovski N, McCabe C, Lee MH, Frohlich I, Paik HI, Zaitlen N, Hacohen N, Stranger B, De Jager P, Mathis D, Regev A, Benoist C. Intersection of population variation and autoimmunity genetics in human T cell activation. Science 2014; 345:1254665. [PMID: 25214635 DOI: 10.1126/science.1254665] [Citation(s) in RCA: 166] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
T lymphocyte activation by antigen conditions adaptive immune responses and immunopathologies, but we know little about its variation in humans and its genetic or environmental roots. We analyzed gene expression in CD4(+) T cells during unbiased activation or in T helper 17 (T(H)17) conditions from 348 healthy participants representing European, Asian, and African ancestries. We observed interindividual variability, most marked for cytokine transcripts, with clear biases on the basis of ancestry, and following patterns more complex than simple T(H)1/2/17 partitions. We identified 39 genetic loci specifically associated in cis with activated gene expression. We further fine-mapped and validated a single-base variant that modulates YY1 binding and the activity of an enhancer element controlling the autoimmune-associated IL2RA gene, affecting its activity in activated but not regulatory T cells. Thus, interindividual variability affects the fundamental immunologic process of T helper activation, with important connections to autoimmune disease.
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Affiliation(s)
- Chun Jimmie Ye
- Broad Institute of Massachusetts Institute of Technology (MIT) and Harvard, Cambridge, MA 02142, USA
| | - Ting Feng
- Division of Immunology, Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Ho-Keun Kwon
- Division of Immunology, Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Towfique Raj
- Broad Institute of Massachusetts Institute of Technology (MIT) and Harvard, Cambridge, MA 02142, USA. Program in Translational NeuroPsychiatric Genomics, Institute for the Neurosciences, Departments of Neurology and Psychiatry, Brigham and Women's Hospital, Boston, MA 02115, USA
| | - Michael T Wilson
- Division of Immunology, Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Natasha Asinovski
- Division of Immunology, Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Cristin McCabe
- Broad Institute of Massachusetts Institute of Technology (MIT) and Harvard, Cambridge, MA 02142, USA. Program in Translational NeuroPsychiatric Genomics, Institute for the Neurosciences, Departments of Neurology and Psychiatry, Brigham and Women's Hospital, Boston, MA 02115, USA
| | - Michelle H Lee
- Program in Translational NeuroPsychiatric Genomics, Institute for the Neurosciences, Departments of Neurology and Psychiatry, Brigham and Women's Hospital, Boston, MA 02115, USA
| | - Irene Frohlich
- Program in Translational NeuroPsychiatric Genomics, Institute for the Neurosciences, Departments of Neurology and Psychiatry, Brigham and Women's Hospital, Boston, MA 02115, USA
| | - Hyun-il Paik
- Division of Immunology, Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Noah Zaitlen
- Department of Medicine Lung Biology Center, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Nir Hacohen
- Division of Immunology, Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Barbara Stranger
- Section of Genetic Medicine, University of Chicago, Chicago, IL 60637, USA
| | - Philip De Jager
- Broad Institute of Massachusetts Institute of Technology (MIT) and Harvard, Cambridge, MA 02142, USA. Program in Translational NeuroPsychiatric Genomics, Institute for the Neurosciences, Departments of Neurology and Psychiatry, Brigham and Women's Hospital, Boston, MA 02115, USA
| | - Diane Mathis
- Broad Institute of Massachusetts Institute of Technology (MIT) and Harvard, Cambridge, MA 02142, USA. Division of Immunology, Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Aviv Regev
- Broad Institute of Massachusetts Institute of Technology (MIT) and Harvard, Cambridge, MA 02142, USA. Howard Hughes Medical Institute, Department of Biology, MIT, Cambridge, MA 02139, USA.
| | - Christophe Benoist
- Broad Institute of Massachusetts Institute of Technology (MIT) and Harvard, Cambridge, MA 02142, USA. Division of Immunology, Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA 02115, USA.
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47
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Lobato L, Bouzhir-Sima L, Yamashita T, Wilson MT, Vos MH, Liebl U. Dynamics of the heme-binding bacterial gas-sensing dissimilative nitrate respiration regulator (DNR) and activation barriers for ligand binding and escape. J Biol Chem 2014; 289:26514-26524. [PMID: 25037216 DOI: 10.1074/jbc.m114.571398] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
DNR (dissimilative nitrate respiration regulator) is a heme-binding transcription factor that is involved in the regulation of denitrification in Pseudomonas aeruginosa. In the ferrous deoxy state, the heme is 6-coordinate; external NO and CO can replace an internal ligand. Using fluorescence anisotropy, we show that high-affinity sequence-specific DNA binding occurs only when the heme is nitrosylated, consistent with the proposed function of DNR as NO sensor and transcriptional activator. This role is moreover supported by the NO "trapping" properties revealed by ultrafast spectroscopy that are similar to those of other heme-based NO sensor proteins. Dissociated CO-heme pairs rebind in an essentially barrierless way. This process competes with migration out of the heme pocket. The latter process is thermally activated (Ea ∼ 7 kJ/mol). This result is compared with other heme proteins, including the homologous CO sensor/transcription factor CooA, variants of the 5-coordinate mycobacterial sensor DosT and the electron transfer protein cytochrome c. This comparison indicates that thermal activation of ligand escape from the heme pocket is specific for systems where an external ligand replaces an internal one. The origin of this finding and possible implications are discussed.
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Affiliation(s)
- Laura Lobato
- Laboratory for Optics and Biosciences, CNRS, Ecole Polytechnique, 91128 Palaiseau, France,; INSERM U696, 91128 Palaiseau, France
| | - Latifa Bouzhir-Sima
- Laboratory for Optics and Biosciences, CNRS, Ecole Polytechnique, 91128 Palaiseau, France,; INSERM U696, 91128 Palaiseau, France
| | - Taku Yamashita
- Laboratory of Analytical Chemistry, Graduate School of Pharmaceutical Sciences, Osaka University, Yamadaoka, Suita, Osaka 565-0871, Japan, and
| | - Michael T Wilson
- School of Biological Sciences, University of Essex, Wivenhoe Park, Colchester C04 3SQ, United Kingdom
| | - Marten H Vos
- Laboratory for Optics and Biosciences, CNRS, Ecole Polytechnique, 91128 Palaiseau, France,; INSERM U696, 91128 Palaiseau, France,.
| | - Ursula Liebl
- Laboratory for Optics and Biosciences, CNRS, Ecole Polytechnique, 91128 Palaiseau, France,; INSERM U696, 91128 Palaiseau, France,.
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48
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Strader MB, Hicks WA, Kassa T, Singleton E, Soman J, Olson JS, Weiss MJ, Mollan TL, Wilson MT, Alayash AI. Post-translational transformation of methionine to aspartate is catalyzed by heme iron and driven by peroxide: a novel subunit-specific mechanism in hemoglobin. J Biol Chem 2014; 289:22342-57. [PMID: 24939847 DOI: 10.1074/jbc.m114.568980] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
A pathogenic V67M mutation occurs at the E11 helical position within the heme pockets of variant human fetal and adult hemoglobins (Hb). Subsequent post-translational modification of Met to Asp was reported in γ subunits of human fetal Hb Toms River (γ67(E11)Val → Met) and β subunits of adult Hb (HbA) Bristol-Alesha (β67(E11)Val → Met) that were associated with hemolytic anemia. Using kinetic, proteomic, and crystal structural analysis, we were able to show that the Met → Asp transformation involves heme cycling through its oxoferryl state in the recombinant versions of both proteins. The conversion to Met and Asp enhanced the spontaneous autoxidation of the mutants relative to wild-type HbA and human fetal Hb, and the levels of Asp were elevated with increasing levels of hydrogen peroxide (H2O2). Using H2(18)O2, we verified incorporation of (18)O into the Asp carboxyl side chain confirming the role of H2O2 in the oxidation of the Met side chain. Under similar experimental conditions, there was no conversion to Asp at the αMet(E11) position in the corresponding HbA Evans (α62(E11)Val → Met). The crystal structures of the three recombinant Met(E11) mutants revealed similar thioether side chain orientations. However, as in the solution experiments, autoxidation of the Hb mutant crystals leads to electron density maps indicative of Asp(E11) formation in β subunits but not in α subunits. This novel post-translational modification highlights the nonequivalence of human Hb α, β, and γ subunits with respect to redox reactivity and may have direct implications to α/β hemoglobinopathies and design of oxidatively stable Hb-based oxygen therapeutics.
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Affiliation(s)
- Michael Brad Strader
- From the Laboratory of Biochemistry and Vascular Biology, Center for Biologics Evaluation and Research, Food and Drug Administration, Bethesda, Maryland 20892
| | - Wayne A Hicks
- From the Laboratory of Biochemistry and Vascular Biology, Center for Biologics Evaluation and Research, Food and Drug Administration, Bethesda, Maryland 20892
| | - Tigist Kassa
- From the Laboratory of Biochemistry and Vascular Biology, Center for Biologics Evaluation and Research, Food and Drug Administration, Bethesda, Maryland 20892
| | - Eileen Singleton
- the Department of Biochemistry and Cell Biology, Rice University, Houston, Texas 77251
| | - Jayashree Soman
- the Department of Biochemistry and Cell Biology, Rice University, Houston, Texas 77251
| | - John S Olson
- the Department of Biochemistry and Cell Biology, Rice University, Houston, Texas 77251
| | - Mitchell J Weiss
- the Childrens Hospital of Philadelphia, Philadelphia, Pennsylvania 19104, and
| | - Todd L Mollan
- From the Laboratory of Biochemistry and Vascular Biology, Center for Biologics Evaluation and Research, Food and Drug Administration, Bethesda, Maryland 20892
| | - Michael T Wilson
- the Department of Biological Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, United Kingdom
| | - Abdu I Alayash
- From the Laboratory of Biochemistry and Vascular Biology, Center for Biologics Evaluation and Research, Food and Drug Administration, Bethesda, Maryland 20892,
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Wong JT, Banerji A, Lax TP, Long A, Wilson MT, Sokol C. Rituxan Hypersensitivity and Management. J Allergy Clin Immunol 2014. [DOI: 10.1016/j.jaci.2013.12.930] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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50
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Lax TP, Banerji A, Wong JT, Wilson MT, Long A. Risk Stratification For Paclitaxel-Induced Hypersensitivity Reactions Improves Quality Of Care. J Allergy Clin Immunol 2014. [DOI: 10.1016/j.jaci.2013.12.558] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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