1
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Ortmayer M, Hardy FJ, Quesne MG, Fisher K, Levy C, Heyes DJ, Catlow CRA, de Visser SP, Rigby SEJ, Hay S, Green AP. A Noncanonical Tryptophan Analogue Reveals an Active Site Hydrogen Bond Controlling Ferryl Reactivity in a Heme Peroxidase. JACS AU 2021; 1:913-918. [PMID: 34337604 PMCID: PMC8317151 DOI: 10.1021/jacsau.1c00145] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Nature employs high-energy metal-oxo intermediates embedded within enzyme active sites to perform challenging oxidative transformations with remarkable selectivity. Understanding how different local metal-oxo coordination environments control intermediate reactivity and catalytic function is a long-standing objective. However, conducting structure-activity relationships directly in active sites has proven challenging due to the limited range of amino acid substitutions achievable within the constraints of the genetic code. Here, we use an expanded genetic code to examine the impact of hydrogen bonding interactions on ferryl heme structure and reactivity, by replacing the N-H group of the active site Trp51 of cytochrome c peroxidase by an S atom. Removal of a single hydrogen bond stabilizes the porphyrin π-cation radical state of CcP W191F compound I. In contrast, this modification leads to more basic and reactive neutral ferryl heme states, as found in CcP W191F compound II and the wild-type ferryl heme-Trp191 radical pair of compound I. This increased reactivity manifests in a >60-fold activity increase toward phenolic substrates but remarkably has negligible effects on oxidation of the biological redox partner cytc. Our data highlight how Trp51 tunes the lifetimes of key ferryl intermediates and works in synergy with the redox active Trp191 and a well-defined substrate binding site to regulate catalytic function. More broadly, this work shows how noncanonical substitutions can advance our understanding of active site features governing metal-oxo structure and reactivity.
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Affiliation(s)
- Mary Ortmayer
- Department
of Chemistry and Manchester Institute of Biotechnology, The University of Manchester, 131 Princess Street, Manchester, M1 7DN, United Kingdom
| | - Florence J. Hardy
- Department
of Chemistry and Manchester Institute of Biotechnology, The University of Manchester, 131 Princess Street, Manchester, M1 7DN, United Kingdom
| | - Matthew G. Quesne
- Research
Complex at Harwell, Rutherford Appleton Laboratory, Harwell Oxford, Didcot, Oxon OX11 0FA, United
Kingdom
- Cardiff
University, School of Chemistry, Main Building, Park Place, Cardiff CF10
3AT, United Kingdom
| | - Karl Fisher
- Department
of Chemistry and Manchester Institute of Biotechnology, The University of Manchester, 131 Princess Street, Manchester, M1 7DN, United Kingdom
| | - Colin Levy
- Department
of Chemistry and Manchester Institute of Biotechnology, The University of Manchester, 131 Princess Street, Manchester, M1 7DN, United Kingdom
| | - Derren J. Heyes
- Department
of Chemistry and Manchester Institute of Biotechnology, The University of Manchester, 131 Princess Street, Manchester, M1 7DN, United Kingdom
| | - C. Richard A. Catlow
- Research
Complex at Harwell, Rutherford Appleton Laboratory, Harwell Oxford, Didcot, Oxon OX11 0FA, United
Kingdom
- Cardiff
University, School of Chemistry, Main Building, Park Place, Cardiff CF10
3AT, United Kingdom
- Kathleen
Lonsdale Materials Chemistry, Department of Chemistry, University College London, 20 Gordon Street, London, Western Central 1H 0AJ, United Kingdom
| | - Sam P. de Visser
- Department
of Chemical Engineering and Analytical Science & Manchester Institute
of Biotechnology, The University of Manchester, 131 Princess Street, Manchester, M1 7DN, United Kingdom
| | - Stephen E. J. Rigby
- Department
of Chemistry and Manchester Institute of Biotechnology, The University of Manchester, 131 Princess Street, Manchester, M1 7DN, United Kingdom
| | - Sam Hay
- Department
of Chemistry and Manchester Institute of Biotechnology, The University of Manchester, 131 Princess Street, Manchester, M1 7DN, United Kingdom
| | - Anthony P. Green
- Department
of Chemistry and Manchester Institute of Biotechnology, The University of Manchester, 131 Princess Street, Manchester, M1 7DN, United Kingdom
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2
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Ortmayer M, Fisher K, Basran J, Wolde-Michael EM, Heyes DJ, Levy C, Lovelock SL, Anderson JLR, Raven EL, Hay S, Rigby SEJ, Green AP. Rewiring the "Push-Pull" Catalytic Machinery of a Heme Enzyme Using an Expanded Genetic Code. ACS Catal 2020; 10:2735-2746. [PMID: 32550044 PMCID: PMC7273622 DOI: 10.1021/acscatal.9b05129] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Revised: 01/22/2020] [Indexed: 01/14/2023]
Abstract
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Nature
employs a limited number of genetically encoded axial ligands
to control diverse heme enzyme activities. Deciphering the functional
significance of these ligands requires a quantitative understanding of how their electron-donating
capabilities modulate the structures and reactivities of the iconic
ferryl intermediates compounds I and II. However, probing these relationships
experimentally has proven to be challenging as ligand substitutions
accessible via conventional mutagenesis do not allow fine tuning of
electron donation and typically abolish catalytic function. Here,
we exploit engineered translation components to replace the histidine
ligand of cytochrome c peroxidase (CcP) by a less electron-donating Nδ-methyl histidine (Me-His) with little effect on the enzyme structure.
The rate of formation (k1) and the reactivity
(k2) of compound I are unaffected by ligand
substitution. In contrast, proton-coupled electron transfer to compound
II (k3) is 10-fold slower in CcP Me-His, providing a direct link between electron donation
and compound II reactivity, which can be explained by weaker electron
donation from the Me-His ligand (“the push”) affording
an electron-deficient ferryl oxygen with reduced proton affinity (“the
pull”). The deleterious effects of the Me-His ligand can be
fully compensated by introducing a W51F mutation designed to increase
“the pull” by removing a hydrogen bond to the ferryl
oxygen. Analogous substitutions in ascorbate peroxidase lead to similar
activity trends to those observed in CcP, suggesting
that a common mechanistic strategy is employed by enzymes using distinct
electron transfer pathways. Our study highlights how noncanonical
active site substitutions can be used to directly probe and deconstruct
highly evolved bioinorganic mechanisms.
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Affiliation(s)
- Mary Ortmayer
- Manchester Institute of Biotechnology, School of Chemistry, University of Manchester, 131 Princess Street, Manchester M1 7DN, U.K
| | - Karl Fisher
- Manchester Institute of Biotechnology, School of Chemistry, University of Manchester, 131 Princess Street, Manchester M1 7DN, U.K
| | - Jaswir Basran
- Department of Molecular and Cell Biology and Leicester Institute of Structural and Chemical Biology, Henry Wellcome Building, University of Leicester, University Road, Leicester LE1 7RH, U.K
| | - Emmanuel M. Wolde-Michael
- Manchester Institute of Biotechnology, School of Chemistry, University of Manchester, 131 Princess Street, Manchester M1 7DN, U.K
| | - Derren J. Heyes
- Manchester Institute of Biotechnology, School of Chemistry, University of Manchester, 131 Princess Street, Manchester M1 7DN, U.K
| | - Colin Levy
- Manchester Institute of Biotechnology, School of Chemistry, University of Manchester, 131 Princess Street, Manchester M1 7DN, U.K
| | - Sarah L. Lovelock
- Manchester Institute of Biotechnology, School of Chemistry, University of Manchester, 131 Princess Street, Manchester M1 7DN, U.K
| | - J. L. Ross Anderson
- School of Biochemistry, University of Bristol, University Walk, Bristol BS8 1TD, U.K
| | - Emma L. Raven
- School of Chemistry, Cantock’s Close, Bristol BS8 1TS, U.K
| | - Sam Hay
- Manchester Institute of Biotechnology, School of Chemistry, University of Manchester, 131 Princess Street, Manchester M1 7DN, U.K
| | - Stephen E. J. Rigby
- Manchester Institute of Biotechnology, School of Chemistry, University of Manchester, 131 Princess Street, Manchester M1 7DN, U.K
| | - Anthony P. Green
- Manchester Institute of Biotechnology, School of Chemistry, University of Manchester, 131 Princess Street, Manchester M1 7DN, U.K
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3
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Chreifi G, Hollingsworth SA, Li H, Tripathi S, Arce AP, Magaña-Garcia HI, Poulos TL. Enzymatic Mechanism of Leishmania major Peroxidase and the Critical Role of Specific Ionic Interactions. Biochemistry 2015; 54:3328-36. [PMID: 25941976 DOI: 10.1021/acs.biochem.5b00338] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Leishmania major peroxidase (LmP) is very similar to the well-known yeast cytochrome c peroxidase (CcP). Both enzymes catalyze the peroxidation of cytochrome c. Like CcP, LmP reacts with H2O2 to form Compound I, which consists of a ferryl heme and a Trp radical, Fe(IV)═O;Trp(•+). Cytochrome c (Cytc) reduces the Trp radical to give Compound II, Fe(IV)═O;Trp, which is followed by an intramolecular electron transfer to give Fe(III)-OH;Trp(•+), and in the last step, Cytc reduces the Trp radical. In this study, we have used steady-state and single-turnover kinetics to improve our understanding of the overall mechanism of LmP catalysis. While the activity of CcP greatly increases with ionic strength, the kcat for LmP remains relatively constant at all ionic strengths tested. Therefore, unlike CcP, where dissociation of oxidized Cytc is limiting at low ionic strengths, association/dissociation reactions are not limiting at any ionic strength in LmP. We conclude that in LmP, the intramolecular electron transfer reaction, Fe(IV)═O;Trp to Fe(III)-OH;Trp(•+), is limiting at all ionic strengths. Unlike CcP, LmP depends on key intermolecular ion pairs to form the electron transfer competent complex. Mutating these sites causes the initial rate of association to decrease by 2 orders of magnitude and a substantial decrease in kcat. The drop in kcat is due to a switch in the rate-limiting step of the mutants from intramolecular electron transfer to the rate of association in forming the LmP-LmCytc complex. These studies show that while LmP and CcP form very similar complexes and exhibit similar activities, they substantially differ in how their activity changes as a function of ionic strength. This difference is primarily due to the heavy reliance of LmP on highly specific intermolecular ion pairs, while CcP relies mainly on nonpolar interactions.
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Affiliation(s)
- Georges Chreifi
- †Department of Molecular Biology and Biochemistry, ‡Department of Chemistry, and §Department of Pharmaceutical Sciences, University of California, Irvine, California 92697-3900, United States
| | - Scott A Hollingsworth
- †Department of Molecular Biology and Biochemistry, ‡Department of Chemistry, and §Department of Pharmaceutical Sciences, University of California, Irvine, California 92697-3900, United States
| | - Huiying Li
- †Department of Molecular Biology and Biochemistry, ‡Department of Chemistry, and §Department of Pharmaceutical Sciences, University of California, Irvine, California 92697-3900, United States
| | - Sarvind Tripathi
- †Department of Molecular Biology and Biochemistry, ‡Department of Chemistry, and §Department of Pharmaceutical Sciences, University of California, Irvine, California 92697-3900, United States
| | - Anton P Arce
- †Department of Molecular Biology and Biochemistry, ‡Department of Chemistry, and §Department of Pharmaceutical Sciences, University of California, Irvine, California 92697-3900, United States
| | - Hugo I Magaña-Garcia
- †Department of Molecular Biology and Biochemistry, ‡Department of Chemistry, and §Department of Pharmaceutical Sciences, University of California, Irvine, California 92697-3900, United States
| | - Thomas L Poulos
- †Department of Molecular Biology and Biochemistry, ‡Department of Chemistry, and §Department of Pharmaceutical Sciences, University of California, Irvine, California 92697-3900, United States
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4
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Yu F, Cangelosi VM, Zastrow ML, Tegoni M, Plegaria JS, Tebo AG, Mocny CS, Ruckthong L, Qayyum H, Pecoraro VL. Protein design: toward functional metalloenzymes. Chem Rev 2014; 114:3495-578. [PMID: 24661096 PMCID: PMC4300145 DOI: 10.1021/cr400458x] [Citation(s) in RCA: 329] [Impact Index Per Article: 32.9] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Fangting Yu
- University of Michigan, Ann Arbor, Michigan 48109, United States
| | | | | | | | | | - Alison G. Tebo
- University of Michigan, Ann Arbor, Michigan 48109, United States
| | | | - Leela Ruckthong
- University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Hira Qayyum
- University of Michigan, Ann Arbor, Michigan 48109, United States
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5
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Murphy EJ, Metcalfe CL, Nnamchi C, Moody PCE, Raven EL. Crystal structure of guaiacol and phenol bound to a heme peroxidase. FEBS J 2011; 279:1632-9. [PMID: 22093282 DOI: 10.1111/j.1742-4658.2011.08425.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Guaiacol is a universal substrate for all peroxidases, and its use in a simple colorimetric assay has wide applications. However, its exact binding location has never been defined. Here we report the crystal structures of guaiacol bound to cytochrome c peroxidase (CcP). A related structure with phenol bound is also presented. The CcP-guaiacol and CcP-phenol crystal structures show that both guaiacol and phenol bind at sites distinct from the cytochrome c binding site and from the δ-heme edge, which is known to be the binding site for other substrates. Although neither guaiacol nor phenol is seen bound at the δ-heme edge in the crystal structures, inhibition data and mutagenesis strongly suggest that the catalytic binding site for aromatic compounds is the δ-heme edge in CcP. The functional implications of these observations are discussed in terms of our existing understanding of substrate binding in peroxidases [Gumiero A et al. (2010) Arch Biochem Biophys 500, 13-20].
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Affiliation(s)
- Emma J Murphy
- Department of Chemistry, University of Leicester, Leicester, UK
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6
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Gumiero A, Murphy EJ, Metcalfe CL, Moody PC, Raven EL. An analysis of substrate binding interactions in the heme peroxidase enzymes: A structural perspective. Arch Biochem Biophys 2010; 500:13-20. [DOI: 10.1016/j.abb.2010.02.015] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2010] [Revised: 02/23/2010] [Accepted: 02/27/2010] [Indexed: 11/29/2022]
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7
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Nonaka D, Wariishi H, Welinder KG, Fujii H. Paramagnetic 13C and 15N NMR Analyses of the Push and Pull Effects in Cytochrome c Peroxidase and Coprinus cinereus Peroxidase Variants: Functional Roles of Highly Conserved Amino Acids around Heme. Biochemistry 2009; 49:49-57. [DOI: 10.1021/bi9017285] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Daisuke Nonaka
- Institute for Molecular Science and Okazaki Institute for Integrative Bioscience, National Institutes of Natural Sciences, Myodaiji, Okazaki 444-8787, Japan
| | - Hiroyuki Wariishi
- Faculty of Agriculture, Kyushu University, Hakozaki, Fukuoka 821-8581, Japan
| | - Karen G. Welinder
- Department of Biotechnology, Chemistry and Environmental Engineering, Aalborg University, Sohngaardsholmsvej 49, DK-9000 Aalborg, Denmark
| | - Hiroshi Fujii
- Institute for Molecular Science and Okazaki Institute for Integrative Bioscience, National Institutes of Natural Sciences, Myodaiji, Okazaki 444-8787, Japan
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8
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Borisenko GG, Kapralov AA, Tyurin VA, Maeda A, Stoyanovsky DA, Kagan VE. Molecular design of new inhibitors of peroxidase activity of cytochrome c/cardiolipin complexes: fluorescent oxadiazole-derivatized cardiolipin. Biochemistry 2009; 47:13699-710. [PMID: 19053260 DOI: 10.1021/bi801507s] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Interaction of a mitochondria-specific anionic phospholipid, cardiolipin (CL), with an intermembrane protein, cytochrome c (cyt c), yields a peroxidase complex. During apoptosis, the complex induces accumulation of CL oxidation products that are essential for detachment of cyt c from the mitochondrial membrane, induction of permeability transition, and release of proapoptotic factors into the cytosol. Therefore, suppression of the peroxidase activity and prevention of CL oxidation may lead to discovery of new antiapoptotic drugs. Here, we report a new approach to regulate the cyt c peroxidase activity by using modified CL with an oxidizable and fluorescent 7-nitro-2,1,3-benzoxadiazole (NBD) moiety (NBD-CL). We demonstrate that NBD-CL forms high-affinity complexes with cyt c and blocks cyt c-catalyzed oxidation of several peroxidase substrates, cyt c self-oxidation, and, most importantly, inhibits cyt c-dependent oxidation of polyunsaturated tetralinoleoyl CL (TLCL) and accumulation of TLCL hydroperoxides. Electrospray ionization mass spectrometry and fluorescence analysis revealed that oxidation and cleavage of the NBD moiety of NBD-CL underlie the inhibition mechanism. We conclude that modified CL combining a nonoxidizable monounsaturated trioleoyl CL with a C(12)-NBD fragment undergoes a regiospecific oxidation thereby representing a novel inhibitor of cyt c peroxidase activity.
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Affiliation(s)
- G G Borisenko
- Research Institute of Physico-Chemical Medicine, Moscow, Russian Federation.
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9
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Ardissone S, Laurenti E, Frendo P, Ghibaudi EM, Puppo A. Single-site mutations on the catalase–peroxidase from Sinorhizobium meliloti: role of the distal Gly and the three amino acids of the putative intrinsic cofactor. J Biol Inorg Chem 2005; 10:813-26. [PMID: 16217641 DOI: 10.1007/s00775-005-0032-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2005] [Accepted: 09/12/2005] [Indexed: 10/25/2022]
Abstract
KatB is the only catalase-peroxidase identified so far in Sinorhizobium meliloti. It plays a housekeeping role, as it is expressed throughout all the growth phases of the free-living bacterium and also during symbiosis. This paper describes the functional and structural characterization of the KatB mutants Gly303Ser, Trp95Ala, Trp95Phe, Tyr217Leu, Tyr217Phe and Met243Val carried out by optical and electron spin resonance spectroscopy. The aim of this work was to investigate the involvement of these residues in the catalatic and/or peroxidatic reaction and falls in the frame of the open dispute around the factors that influence the balance between catalatic and peroxidatic activity in heme enzymes. The Gly303 residue is not conserved in any other protein of this family, whereas the Trp95, Tyr217 and Met243 residues are thought to form an intrinsic cofactor that is likely to play a role in intramolecular electron transfer. Spectroscopic investigations show that the Gly303Ser mutant is almost similar to the wild-type KatB and should not be involved in substrate binding. Mutations on Trp95, Tyr217 and Met243 clear out the catalatic activity completely, whereas the peroxidatic activity is maintained or even increased with respect to that of the wild-type enzyme. The k (cat) values obtained for these mutants suggest that Trp95 and Tyr217 form a huge delocalized system that provides a pathway for electron transfer to the heme. Conversely, Met243 is likely to be placed close to the binding site of the organic molecules and plays a crucial role in substrate docking.
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Affiliation(s)
- Silvia Ardissone
- Dipartimento di Chimica I. F. M., Università di Torino, via Pietro Giuria 7, 10125, Turin, Italy
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10
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Abstract
Reactions of substrate-free ferric cytochrome P450cam with peracids to generate Fe=O intermediates have previously been investigated with contradictory results. Using stopped-flow spectrophotometry, the reaction with m-chloroperoxybenzoic acid demonstrated an Fe(IV)=O + porphyrin pi-cation radical (Cpd I) (Egawa, T., Shimada, H., and Ishimura, Y. (1994) Biochem. Biophys. Res. Commun. 201, 1464-1469). By contrast, with peracetic acid, Fe(IV)=O plus a tyrosyl radical were observed by freeze-quench Mossbauer and EPR spectroscopy (Schunemann, V., Jung, C., Trautwein, A. X., Mandon, D., and Weiss, R. (2000) FEBS Lett. 479, 149-154). Our detailed kinetic studies have resolved these contradictory results. At pH >7, a significant fraction of Cpd I is formed transiently, whereas at low pH only a species with a Soret band at 406 nm, presumably Fe(IV)=O + tyrosyl radical, is observed. Evidence for formation of an acylperoxo complex en route to Cpd I was obtained. Because of rapid heme destruction, steps subsequent to formation of the highly oxidized forms could not be fully characterized. Heme destruction was avoided by including peroxidase substrates (e.g. guaiacol), which were oxidized to characteristic peroxidase products as the Fe(III)-P450 was regenerated. Addition of ascorbate to either of the high valent species also reforms the Fe(III) state with only a small loss of heme absorbance. These results indicate that typical peroxidase chemistry occurs with P450cam and offer an explanation for the contrasting results reported earlier. The delineation of improved conditions (pH, temperature, choice of peracid) for generating highly oxidized species with P450cam should be valuable for their further characterization.
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Affiliation(s)
- Tatyana Spolitak
- Department of Biological Chemistry, University of Michigan, Ann Arbor, Michigan 48109-0606, USA
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11
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Eady NAJ, Jesmin NAJ, Servos S, Cass AEG, Nagy JM, Brown KA. Probing the function of Mycobacterium tuberculosis catalase-peroxidase by site-directed mutagenesis. Dalton Trans 2005:3495-500. [PMID: 16315359 DOI: 10.1039/b508448m] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Catalase-peroxidase is a multi-functional heme-dependent enzyme which is well known for its ability to carry out both catalatic and peroxidatic reactions. Catalase-peroxidase from Mycobacterium tuberculosis(mtCP) is of particular interest because this enzyme activates the pro-antitubercular drug isoniazid. It is estimated that 2 billion people are infected with M. tuberculosis, the principal causative agent of tuberculosis, and that 2 million people die from the disease each year. The rise of drug-resistant strains continues to be of critical concern and it is well documented that mutations which reduce activity or inactivate mtCP lead to increased levels of isoniazid resistance in M. tuberculosis. The recent determination of the crystal structure for M. tuberculosis mtCP has aided the understanding of how the enzyme functions and provides a three-dimensional framework for testing hypotheses about the roles of various residues in the active site. Here we report site-directed mutagenesis studies of three conserved residues located near the heme of mtCP, His-108, Trp-107 and Trp-321 including the construction of the double mutant W107F-W321F. Resulting mutants have been purified and their catalatic and peroxidatic activities have been determined. Data are compared in the context of related studies aimed at dissecting the roles of these residues in the different activities of the enzyme. Analyses of single and double mutants studied here emphasise that the hydrogen bonding network surrounding the heme in the active site appears more important for maintenance of catalatic rather than peroxidatic activity in CP enzymes.
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Affiliation(s)
- Nigel A J Eady
- Division of Cell and Molecular Biology, Centre for Molecular Microbiology and Infection, Imperial College London, UK
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12
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Feng M, Tachikawa H, Wang X, Pfister TD, Gengenbach AJ, Lu Y. Resonance Raman spectroscopy of cytochrome c peroxidase variants that mimic manganese peroxidase. J Biol Inorg Chem 2003; 8:699-706. [PMID: 14505074 DOI: 10.1007/s00775-003-0460-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2002] [Accepted: 03/28/2003] [Indexed: 11/28/2022]
Abstract
Cytochrome c peroxidase (C cP) variants with an engineered Mn(II) binding site, including MnC cP [C cP(MI, G41E, V45E, H181D)], MnC cP(W191F), and MnC cP(W191F, W51F), that mimic manganese peroxidase (MnP), have been characterized by resonance Raman (RR) spectroscopy. Analysis of the Raman bands in the 200-700 cm(-1) and 1300-1650 cm(-1) regions indicates that both the coordination and spin state of the heme iron in the variants differ from that of C cP(MI), the recombinant yeast C cP containing additional Met-Ile residues at the N-terminus. At neutral pH the frequencies of the nu(3) mode indicate that a pure five-coordinate heme iron exists in C cP(MI) whereas a six-coordinate low-spin iron is the dominant species in the C cP variants with the engineered Mn(II) binding site. The H181D mutation, which weakens the proximal linkage to the heme iron, may be responsible for these spectral and structural changes. Raman spectra of the variants C cP(MI, W191F) and C cP(MI, W191F, W51F) were also obtained to clarify the structural and functional roles of mutations at two tryptophan sites. The W51F mutation was found to disrupt H-bonding to the distal water molecules and the resulting variants tended to form transitional or mixed coordination states that possess spectral and structural features similar to that of MnP. Such structural features, with a loosened distal water, may facilitate the binding of H(2)O(2) and increase the rate constant for compound I formation. This effect, in addition to the elimination of an H-bond to ferryl oxygen by the same mutation, accounts for the increased MnP specific activity of MnC cP(W191F, W51F).
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Affiliation(s)
- Manliang Feng
- Department of Chemistry, Jackson State University, Box 17910, Jackson, MS 39217-0510, USA
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13
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Watanabe Y, Ueno T. Introduction of P450, Peroxidase, and Catalase Activities into Myoglobin by Site-Directed Mutagenesis: Diverse Reactivities of Compound I. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2003. [DOI: 10.1246/bcsj.76.1309] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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14
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Selassie CD, Garg R, Kapur S, Kurup A, Verma RP, Mekapati SB, Hansch C. Comparative QSAR and the radical toxicity of various functional groups. Chem Rev 2002; 102:2585-605. [PMID: 12105936 DOI: 10.1021/cr940024m] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Cynthia D Selassie
- Chemistry Department, Pomona College, 645 North College Avenue, Claremont, California 91711, USA
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15
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Erman JE, Vitello LB. Yeast cytochrome c peroxidase: mechanistic studies via protein engineering. BIOCHIMICA ET BIOPHYSICA ACTA 2002; 1597:193-220. [PMID: 12044899 DOI: 10.1016/s0167-4838(02)00317-5] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Cytochrome c peroxidase (CcP) is a yeast mitochondrial enzyme that catalyzes the reduction of hydrogen peroxide to water by ferrocytochrome c. It was the first heme enzyme to have its crystallographic structure determined and, as a consequence, has played a pivotal role in developing ideas about structural control of heme protein reactivity. Genetic engineering of the active site of CcP, along with structural, spectroscopic, and kinetic characterization of the mutant proteins has provided considerable insight into the mechanism of hydrogen peroxide activation, oxygen-oxygen bond cleavage, and formation of the higher-oxidation state intermediates in heme enzymes. The catalytic mechanism involves complex formation between cytochrome c and CcP. The cytochrome c/CcP system has been very useful in elucidating the complexities of long-range electron transfer in biological systems, including protein-protein recognition, complex formation, and intracomplex electron transfer processes.
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Affiliation(s)
- James E Erman
- Department of Chemistry and Biochemistry, Northern Illinois University, Normal Rd., DeKalb, IL 60115-2862, USA.
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16
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Iffland A, Gendreizig S, Tafelmeyer P, Johnsson K. Changing the substrate specificity of cytochrome c peroxidase using directed evolution. Biochem Biophys Res Commun 2001; 286:126-32. [PMID: 11485318 DOI: 10.1006/bbrc.2001.5366] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Cytochrome c peroxidase (CCP) from Saccharomyces cerevisiae was subjected to directed molecular evolution to generate mutants with increased activity against 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS). Using a combination of DNA shuffling and saturation mutagenesis, mutants were isolated which possessed more than 20-fold increased activity against ABTS and a 70-fold increased specificity toward ABTS compared to the natural substrate. In contrast, activities against another small organic molecule, guaiacol, were not significantly affected. Mutations at residues Asp224 and Asp217 were responsible for this increase in activity. These two residues are located on the surface of the protein and not in the direct vicinity of the distal cavity of the peroxidase, where small organic substrates are believed to be oxidized. Mutations at position Asp224 also lead to an increased amount of the active holoenzyme expressed in Escherichia coli, favoring the selection of these mutants in the employed colony screen. Possible explanations for the effect of the mutations on the in vitro activity of CCP as well as the increased amount of holoenzyme are discussed.
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Affiliation(s)
- A Iffland
- Institut de Chimie Organique, Université de Lausanne, CH-1015 Lausanne, Switzerland
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Hansch C, Kurup A, Garg R, Gao H. Chem-bioinformatics and QSAR: a review of QSAR lacking positive hydrophobic terms. Chem Rev 2001; 101:619-72. [PMID: 11712499 DOI: 10.1021/cr0000067] [Citation(s) in RCA: 177] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- C Hansch
- Department of Chemistry, Pomona College, Claremont, California 91711, USA
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18
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Regelsberger G, Jakopitsch C, Rüker F, Krois D, Peschek GA, Obinger C. Effect of distal cavity mutations on the formation of compound I in catalase-peroxidases. J Biol Chem 2000; 275:22854-61. [PMID: 10811647 DOI: 10.1074/jbc.m002371200] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Catalase-peroxidases have a predominant catalase activity but differ from monofunctional catalases in exhibiting a substantial peroxidase activity and in having different residues in the heme cavity. We present a kinetic study of the formation of the key intermediate compound I by probing the role of the conserved distal amino acid triad Arg-Trp-His of a recombinant catalase-peroxidase in its reaction with hydrogen peroxide, peroxoacetic acid, and m-chloroperbenzoic acid. Both the wild-type enzyme and six mutants (R119A, R119N, W122F, W122A, H123Q, H123E) have been investigated by steady-state and stopped-flow spectroscopy. The turnover number of catalase activity of R119A is 14.6%, R119N 0.5%, H123E 0.03%, and H123Q 0.02% of wild-type activity. Interestingly, W122F and W122A completely lost their catalase activity but retained their peroxidase activity. Bimolecular rate constants of compound I formation of the wild-type enzyme and the mutants have been determined. The Trp-122 mutants for the first time made it possible to follow the transition of the ferric enzyme to compound I by hydrogen peroxide spectroscopically underlining the important role of Trp-122 in catalase activity. The results demonstrate that the role of the distal His-Arg pair in catalase-peroxidases is important in the heterolytic cleavage of hydrogen peroxide (i.e. compound I formation), whereas the distal tryptophan is essential for compound I reduction by hydrogen peroxide.
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Affiliation(s)
- G Regelsberger
- Institute of Chemistry and the Institute of Applied Microbiology, University of Agricultural Sciences, Muthgasse 18, A-1190 Vienna, Austria
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Adak S, Crooks C, Wang Q, Crane BR, Tainer JA, Getzoff ED, Stuehr DJ. Tryptophan 409 controls the activity of neuronal nitric-oxide synthase by regulating nitric oxide feedback inhibition. J Biol Chem 1999; 274:26907-11. [PMID: 10480900 DOI: 10.1074/jbc.274.38.26907] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The heme of neuronal nitric-oxide synthase participates in oxygen activation but also binds self-generated NO during catalysis resulting in reversible feedback inhibition. We utilized point mutagenesis to investigate if a conserved tryptophan residue (Trp-409), which engages in pi-stacking with the heme and hydrogen bonds to its axial cysteine ligand, helps control catalysis and regulation by NO. Surprisingly, mutants W409F and W409Y were hyperactive compared with the wild type regarding NO synthesis without affecting cytochrome c reduction, reductase-independent N-hydroxyarginine oxidation, or Arg and tetrahydrobiopterin binding. In the absence of Arg, NADPH oxidation measurements showed that electron flux through the heme was actually slower in the Trp-409 mutants than in wild-type nNOS. However, little or no NO complex accumulated during NO synthesis by the mutants, as opposed to the wild type. This difference was potentially related to mutants forming unstable 6-coordinate ferrous-NO complexes under anaerobic conditions even in the presence of Arg and tetrahydrobiopterin. Thus, Trp-409 mutations minimize NO feedback inhibition by preventing buildup of an inactive ferrous-NO complex during the steady state. This overcomes the negative effect of the mutation on electron flux and results in hyperactivity. Conservation of Trp-409 among different NOS suggests that the ability of this residue to regulate heme reduction and NO complex formation is important for enzyme physiologic function.
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Affiliation(s)
- S Adak
- Department of Immunology, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio 44195, USA.
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20
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Hansch C, Gao H. Comparative QSAR: Radical Reactions of Benzene Derivatives in Chemistry and Biology. Chem Rev 1997; 97:2995-3060. [PMID: 11851484 DOI: 10.1021/cr9601021] [Citation(s) in RCA: 112] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
- Corwin Hansch
- Department of Chemistry, Pomona College, Claremont, California 91711
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21
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Millett F, Miller MA, Geren L, Durham B. Electron transfer between cytochrome c and cytochrome c peroxidase. J Bioenerg Biomembr 1995; 27:341-51. [PMID: 8847347 DOI: 10.1007/bf02110103] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The reaction between cytochrome c (CC) and cytochrome c peroxidase (CcP) is a very attractive system for investigating the fundamental mechanism of biological electron transfer. The resting ferric state of CcP is oxidized by hydrogen peroxide to compound I (CMPI) containing an oxyferryl heme and an indolyl radical cation on Trp-191. CMPI is sequentially reduced to CMPII and then to the resting state CcP by two molecules of CC. In this review we discuss the use of a new ruthenium photoreduction technique and other rapid kinetic techniques to address the following important questions: (1) What is the initial electron acceptor in CMPI? (2) What are the true rates of electron transfer from CC to the radical cation and to the oxyferryl heme? (3) What are the binding domains and pathways for electron transfer from CC to the radical cation and the oxyferryl heme? (4) What is the mechanism for the complete reaction under physiological conditions?
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Affiliation(s)
- F Millett
- Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville 72701, USA
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22
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Liu RQ, Geren L, Anderson P, Fairris JL, Peffer N, McKee A, Durham B, Millet F. Design of ruthenium-cytochrome c derivatives to measure electron transfer to cytochrome c peroxidase. Biochimie 1995; 77:549-61. [PMID: 8589066 DOI: 10.1016/0300-9084(96)88171-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
A new technique has been introduced to measure interprotein electron transfer which involves photoexcitation of a tris(bipyridine)ruthenium (Ru) complex covalently attached to one of the proteins. Four different strategies have been developed to specifically attach Ru to protein lysine amino groups, histidine imidazole groups, and cysteine sulhydryl groups. These strategies have been used to prepare more than 20 different singly-labeled Ru-cytochrome c derivatives. The new ruthenium photoexcitation technique has been used to study the mechanism for electron transfer between cytochrome c and cytochrome c peroxidase. Laser excitation of a complex between Ru-cytochrome c and cytochrome c peroxidase compound I results in formation of Ru(II*) which is a strong reducing agent, and rapidly transfers an electron to heme c Fe(III) to form Fe(II). The heme c Fe(II) then rapidly transfers an electron to the Trp-191 radical cation in CMPI. The rate constant for this reaction is 6 x 10(4) s-1 for a horse Ru-cytochrome c derivative labeled at lysine 27, and greater than 10(6) s-1 for yeast Ru-cytochrome c derivatives. A second laser flash results in electron transfer from heme c to the oxyferryl heme in cytochrome c peroxidase compound II with a rate constant of 350 s-1. The ruthenium photoreduction technique has been used to study the interaction domain between the two proteins, the pathway for electron transfer to the radical cation and the oxyferryl heme, and the specific residues in the heme crevice which control the electron transfer properties of the Trp-191 radical cation and the oxyferryl heme.
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Affiliation(s)
- R Q Liu
- Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville 72701, USA
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23
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English AM, Tsaprailis G. Catalytic Structure–Function Relationships in Heme Peroxidases. ADVANCES IN INORGANIC CHEMISTRY 1995. [DOI: 10.1016/s0898-8838(08)60116-6] [Citation(s) in RCA: 70] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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