The Experts below are selected from a list of 2004 Experts worldwide ranked by ideXlab platform
Takashi Hayashi - One of the best experts on this subject based on the ideXlab platform.
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a supramolecular assembly of Hemoproteins formed in a star shaped structure via heme heme pocket interactions
International Journal of Molecular Sciences, 2021Co-Authors: Julian Wong Soon, Koji Oohora, Shota Hirayama, Takashi HayashiAbstract:Proteins have been used as building blocks to provide various supramolecular structures in efforts to develop nano-biomaterials possessing broad biological functionalities. A series of unique structures have been obtained from the engineering of Hemoproteins which contain the iron porphyrin known as heme, as a prosthetic group. This work in developing assembling systems is extended using cytochrome b562, a small electron transfer hemoprotein engineered to include an externally-attached heme moiety. The engineered units, which form a one-dimensional assembly via interprotein heme-heme pocket interactions, are conjugated to an apo-form of hexameric tyrosine-coordinated hemoprotein (apoHTHP) to provide a branching unit promoting the assembly of a star-shaped structure. The incorporation of the heme moiety attached to the protein surface of cytochrome b562 into apoHTHP can be accelerated by elevating the reaction temperature to generate a new assembly. The formation of a new larger assembly structure was confirmed by size exclusion chromatography. The ratio of the heme-containing units in the assemblies was analyzed by UV-Vis spectroscopy and the population of protein units estimated from SDS PAGE suggests the presence of plausible star-shaped structures, which are supported by hydrodynamic diameter data obtained by dynamic light scattering.
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Hemoproteins Reconstituted with Artificial Metal Complexes as Biohybrid Catalysts
Accounts of chemical research, 2019Co-Authors: Koji Oohora, Akira Onoda, Takashi HayashiAbstract:ConspectusIn nature, heme cofactor-containing proteins participate not only in electron transfer and O2 storage and transport but also in biosynthesis and degradation. The simplest and representative cofactor, heme b, is bound within the heme pocket via noncovalent interaction in many Hemoproteins, suggesting that the cofactor is removable from the protein, leaving a unique cavity. Since the cavity functions as a coordination sphere for heme, it is of particular interest to investigate replacement of native heme with an artificial metal complex, because the substituted metal complex will be stabilized in the heme pocket while providing alternative chemical properties. Thus, cofactor substitution has great potential for engineering of Hemoproteins with alternative functions. For these studies, myoglobin has been a focus of our investigations, because it is a well-known oxygen storage hemoprotein. However, the heme pocket of myoglobin has been only arranged for stabilizing the heme-bound dioxygen, so the st...
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substitution of an amino acid residue axially coordinating to the heme molecule in hexameric tyrosine coordinated hemoprotein to enhance peroxidase activity
Journal of Porphyrins and Phthalocyanines, 2017Co-Authors: Tsuyoshi Mashima, Koji Oohora, Takashi HayashiAbstract:To convert an originally tyrosine-coordinated heme to histidine-coordinated heme in hexameric tyrosine-coordinated hemoprotein, HTHP, Tyr45, a residue coordinating to the heme cofactor, and Arg25 located in the distal site are replaced with Phe45 and His25, respectively in each of the subunits of the protein. The obtained HTHP mutant (HTHPR25H/Y45F) was characterized by SDS-PAGE, ESI-TOF MS, dynamic light scattering measurements and size exclusion chromatography. These analyses indicate that HTHPR25H/Y45F maintains its stable hexameric structure with the altered ligation of each of the heme cofactors. Comparison of UV-vis absorption spectra of the ferric-, ferrous-, CO- and CN-forms of HTHPR25H/Y45F with those of several well-known His-ligated Hemoproteins indicates that heme is coordinated by the His25 residue. The reaction of HTHPR25H/Y45F with cumene hydroperoxide produces both cumyl alcohol and acetophenone in a 2.3:1 ratio, indicating that heterolytic O–O bond cleavage dominantly occurs to form the t...
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reconstitution of heme enzymes with artificial metalloporphyrinoids
Methods in Enzymology, 2016Co-Authors: Koji Oohora, Takashi HayashiAbstract:An important strategy used in engineering of Hemoproteins to generate artificial enzymes involves replacement of heme with an artificial cofactor after removal of the native heme cofactor under acidic conditions. Replacement of heme in an enzyme with a nonnatural metalloporphyrinoid can significantly alter the reactivity of the enzyme. This chapter describes the design and synthesis of three types of artificial metalloporphyrinoid cofactors consisting of mono-, di-, and tri-anionic ligands (tetradehydrocorrin, porphycene, and corrole, respectively). In addition, practical procedures for the preparation of apo-Hemoproteins, incorporation of artificial cofactors, and characterization techniques are presented. Furthermore, the representative catalytic activities of artificial enzymes generated by reconstitution of Hemoproteins are summarized.
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supramolecular assembling systems formed by heme heme pocket interactions in Hemoproteins
ChemInform, 2013Co-Authors: Koji Oohora, Akira Onoda, Takashi HayashiAbstract:A native protein in a biological system spontaneously produces large and elegant assemblies via self-assembly or assembly with various biomolecules which provide non-covalent interactions. In this context, the protein plays a key role in construction of a unique supramolecular structure operating as a functional system. Our group has recently highlighted the structure and function of Hemoproteins reconstituted with artificially created heme analogs. The heme molecule is a replaceable cofactor of several Hemoproteins. Here, we focus on the successive supramolecular protein assemblies driven by heme–heme pocket interactions to afford various examples of protein fibers, networks and three-dimensional clusters in which an artificial heme moiety is introduced onto the surface of a hemoprotein via covalent linkage and the native heme cofactor is removed from the heme pocket. This strategy is found to be useful for constructing hybrid materials with an electrode or with nanoparticles. The new systems described herein are expected to lead to the generation of various biomaterials with functions and characteristic physicochemical properties similar to those of Hemoproteins.
Koji Oohora - One of the best experts on this subject based on the ideXlab platform.
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a supramolecular assembly of Hemoproteins formed in a star shaped structure via heme heme pocket interactions
International Journal of Molecular Sciences, 2021Co-Authors: Julian Wong Soon, Koji Oohora, Shota Hirayama, Takashi HayashiAbstract:Proteins have been used as building blocks to provide various supramolecular structures in efforts to develop nano-biomaterials possessing broad biological functionalities. A series of unique structures have been obtained from the engineering of Hemoproteins which contain the iron porphyrin known as heme, as a prosthetic group. This work in developing assembling systems is extended using cytochrome b562, a small electron transfer hemoprotein engineered to include an externally-attached heme moiety. The engineered units, which form a one-dimensional assembly via interprotein heme-heme pocket interactions, are conjugated to an apo-form of hexameric tyrosine-coordinated hemoprotein (apoHTHP) to provide a branching unit promoting the assembly of a star-shaped structure. The incorporation of the heme moiety attached to the protein surface of cytochrome b562 into apoHTHP can be accelerated by elevating the reaction temperature to generate a new assembly. The formation of a new larger assembly structure was confirmed by size exclusion chromatography. The ratio of the heme-containing units in the assemblies was analyzed by UV-Vis spectroscopy and the population of protein units estimated from SDS PAGE suggests the presence of plausible star-shaped structures, which are supported by hydrodynamic diameter data obtained by dynamic light scattering.
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Hemoproteins Reconstituted with Artificial Metal Complexes as Biohybrid Catalysts
Accounts of chemical research, 2019Co-Authors: Koji Oohora, Akira Onoda, Takashi HayashiAbstract:ConspectusIn nature, heme cofactor-containing proteins participate not only in electron transfer and O2 storage and transport but also in biosynthesis and degradation. The simplest and representative cofactor, heme b, is bound within the heme pocket via noncovalent interaction in many Hemoproteins, suggesting that the cofactor is removable from the protein, leaving a unique cavity. Since the cavity functions as a coordination sphere for heme, it is of particular interest to investigate replacement of native heme with an artificial metal complex, because the substituted metal complex will be stabilized in the heme pocket while providing alternative chemical properties. Thus, cofactor substitution has great potential for engineering of Hemoproteins with alternative functions. For these studies, myoglobin has been a focus of our investigations, because it is a well-known oxygen storage hemoprotein. However, the heme pocket of myoglobin has been only arranged for stabilizing the heme-bound dioxygen, so the st...
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substitution of an amino acid residue axially coordinating to the heme molecule in hexameric tyrosine coordinated hemoprotein to enhance peroxidase activity
Journal of Porphyrins and Phthalocyanines, 2017Co-Authors: Tsuyoshi Mashima, Koji Oohora, Takashi HayashiAbstract:To convert an originally tyrosine-coordinated heme to histidine-coordinated heme in hexameric tyrosine-coordinated hemoprotein, HTHP, Tyr45, a residue coordinating to the heme cofactor, and Arg25 located in the distal site are replaced with Phe45 and His25, respectively in each of the subunits of the protein. The obtained HTHP mutant (HTHPR25H/Y45F) was characterized by SDS-PAGE, ESI-TOF MS, dynamic light scattering measurements and size exclusion chromatography. These analyses indicate that HTHPR25H/Y45F maintains its stable hexameric structure with the altered ligation of each of the heme cofactors. Comparison of UV-vis absorption spectra of the ferric-, ferrous-, CO- and CN-forms of HTHPR25H/Y45F with those of several well-known His-ligated Hemoproteins indicates that heme is coordinated by the His25 residue. The reaction of HTHPR25H/Y45F with cumene hydroperoxide produces both cumyl alcohol and acetophenone in a 2.3:1 ratio, indicating that heterolytic O–O bond cleavage dominantly occurs to form the t...
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reconstitution of heme enzymes with artificial metalloporphyrinoids
Methods in Enzymology, 2016Co-Authors: Koji Oohora, Takashi HayashiAbstract:An important strategy used in engineering of Hemoproteins to generate artificial enzymes involves replacement of heme with an artificial cofactor after removal of the native heme cofactor under acidic conditions. Replacement of heme in an enzyme with a nonnatural metalloporphyrinoid can significantly alter the reactivity of the enzyme. This chapter describes the design and synthesis of three types of artificial metalloporphyrinoid cofactors consisting of mono-, di-, and tri-anionic ligands (tetradehydrocorrin, porphycene, and corrole, respectively). In addition, practical procedures for the preparation of apo-Hemoproteins, incorporation of artificial cofactors, and characterization techniques are presented. Furthermore, the representative catalytic activities of artificial enzymes generated by reconstitution of Hemoproteins are summarized.
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supramolecular assembling systems formed by heme heme pocket interactions in Hemoproteins
ChemInform, 2013Co-Authors: Koji Oohora, Akira Onoda, Takashi HayashiAbstract:A native protein in a biological system spontaneously produces large and elegant assemblies via self-assembly or assembly with various biomolecules which provide non-covalent interactions. In this context, the protein plays a key role in construction of a unique supramolecular structure operating as a functional system. Our group has recently highlighted the structure and function of Hemoproteins reconstituted with artificially created heme analogs. The heme molecule is a replaceable cofactor of several Hemoproteins. Here, we focus on the successive supramolecular protein assemblies driven by heme–heme pocket interactions to afford various examples of protein fibers, networks and three-dimensional clusters in which an artificial heme moiety is introduced onto the surface of a hemoprotein via covalent linkage and the native heme cofactor is removed from the heme pocket. This strategy is found to be useful for constructing hybrid materials with an electrode or with nanoparticles. The new systems described herein are expected to lead to the generation of various biomaterials with functions and characteristic physicochemical properties similar to those of Hemoproteins.
Brian M Hoffman - One of the best experts on this subject based on the ideXlab platform.
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Electron Paramagnetic Resonance and Electron-Nuclear Double Resonance Studies of the Reactions of Cryogenerated Hydroperoxoferric−Hemoprotein Intermediates
2016Co-Authors: Roman Davydov, Mikhail Laryukhin, Masanori Sono, John H Dawson, Amy Ledbetter-rogers, Brian M HoffmanAbstract:ABSTRACT: The fleeting ferric peroxo and hydroperoxo inter-mediates of dioxygen activation by Hemoproteins can be readily trapped and characterized during cryoradiolytic reduction of ferrous hemoprotein−O2 complexes at 77 K. Previous cryoannealing studies suggested that the relaxation of cryogenerated hydroperoxoferric intermediates of myoglobin (Mb), hemoglobin, and horseradish peroxidase (HRP), either trapped directly at 77 K or generated by cryoannealing of a trapped peroxo-ferric state, proceeds through dissociation of bound H2O2 and formation of the ferric heme without formation of the ferryl porphyrin π-cation radical intermediate, compound I (Cpd I). Herein we have reinvestigated the mechanism of decays of the cryogenerated hydroperoxyferric intermediates of α- and β-chains of human hemoglobin, HRP, and chloroperoxidase (CPO). The latter two proteins are well-known to form spectroscopically detectable quasistable Cpds I. Peroxoferric intermediates are trapped during 77 K cryoreduction of oxy Mb, α-chains, and β-chains of human hemoglobin and CPO. They convert into hydroperoxoferric intermediates durin
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electron paramagnetic resonance and electron nuclear double resonance studies of the reactions of cryogenerated hydroperoxoferric hemoprotein intermediates
Biochemistry, 2014Co-Authors: Roman Davydov, Mikhail Laryukhin, Amy Ledbetterrogers, Masanori Sono, John H Dawson, Brian M HoffmanAbstract:The fleeting ferric peroxo and hydroperoxo intermediates of dioxygen activation by Hemoproteins can be readily trapped and characterized during cryoradiolytic reduction of ferrous hemoprotein–O2 complexes at 77 K. Previous cryoannealing studies suggested that the relaxation of cryogenerated hydroperoxoferric intermediates of myoglobin (Mb), hemoglobin, and horseradish peroxidase (HRP), either trapped directly at 77 K or generated by cryoannealing of a trapped peroxo-ferric state, proceeds through dissociation of bound H2O2 and formation of the ferric heme without formation of the ferryl porphyrin π-cation radical intermediate, compound I (Cpd I). Herein we have reinvestigated the mechanism of decays of the cryogenerated hydroperoxyferric intermediates of α- and β-chains of human hemoglobin, HRP, and chloroperoxidase (CPO). The latter two proteins are well-known to form spectroscopically detectable quasistable Cpds I. Peroxoferric intermediates are trapped during 77 K cryoreduction of oxy Mb, α-chains, and...
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epr and endor studies of fe ii Hemoproteins reduced and oxidized at 77 k
Journal of Biological Inorganic Chemistry, 2008Co-Authors: Roman Davydov, Brian M HoffmanAbstract:γ-irradiation of frozen solutions of Fe(II) Hemoproteins at 77 K generates both electron paramagnetic resonance (EPR) active singly reduced and oxidized heme centers trapped in the conformation of the Fe(II) precursors. The reduction products of pentacoordinate (S = 2) Fe(II) globins, peroxidases and cytochrome P450cam show EPR and electron–nuclear double resonance (ENDOR) spectra characteristic of (3d7) Fe(I) species. In addition, cryoreduced Fe(II) α-chains of hemoglobin and myoglobin exhibit an S = 3/2 spin state produced by antiferromagnetic coupling between a porphyrin anion radical and pentacoordinate (S = 2) Fe(II). The spectra of cryoreduced forms of Fe(II) hemoglobin α-chains and deoxymyoglobin reveal that the Fe(II) precursors adopt multiple conformational substates. Reduction of hexacoordinate Fe(II) cytochrome c and cytochrome b5 as well as carboxy complexes of deoxyglobins produces only Fe(II) porphyrin π-anion radical species. The low-valent hemoprotein intermediates produced by cryoreduction convert to the Fe(II) states at T > 200 K. Cryogenerated Fe(III) cytochrome c and cytochrome b5 have spectra similar to these for the resting Fe(III) states, whereas the spectra of the products of cryooxidation of pentacoordinate Fe(II) globins and peroxidases are different. Cryooxidation of CO–Fe(II) globins generates Fe(III) hemes with quantum-mechanically admixed S = 3/2, 5/2 ground states. The trapped Fe(III) species relax to the equilibrium ferric states upon annealing at T > 190 K. Both cryooxidized and reduced centers provide very sensitive EPR/ENDOR structure probes of the EPR-silent Fe(II) state.
Roman Davydov - One of the best experts on this subject based on the ideXlab platform.
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Electron Paramagnetic Resonance and Electron-Nuclear Double Resonance Studies of the Reactions of Cryogenerated Hydroperoxoferric−Hemoprotein Intermediates
2016Co-Authors: Roman Davydov, Mikhail Laryukhin, Masanori Sono, John H Dawson, Amy Ledbetter-rogers, Brian M HoffmanAbstract:ABSTRACT: The fleeting ferric peroxo and hydroperoxo inter-mediates of dioxygen activation by Hemoproteins can be readily trapped and characterized during cryoradiolytic reduction of ferrous hemoprotein−O2 complexes at 77 K. Previous cryoannealing studies suggested that the relaxation of cryogenerated hydroperoxoferric intermediates of myoglobin (Mb), hemoglobin, and horseradish peroxidase (HRP), either trapped directly at 77 K or generated by cryoannealing of a trapped peroxo-ferric state, proceeds through dissociation of bound H2O2 and formation of the ferric heme without formation of the ferryl porphyrin π-cation radical intermediate, compound I (Cpd I). Herein we have reinvestigated the mechanism of decays of the cryogenerated hydroperoxyferric intermediates of α- and β-chains of human hemoglobin, HRP, and chloroperoxidase (CPO). The latter two proteins are well-known to form spectroscopically detectable quasistable Cpds I. Peroxoferric intermediates are trapped during 77 K cryoreduction of oxy Mb, α-chains, and β-chains of human hemoglobin and CPO. They convert into hydroperoxoferric intermediates durin
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electron paramagnetic resonance and electron nuclear double resonance studies of the reactions of cryogenerated hydroperoxoferric hemoprotein intermediates
Biochemistry, 2014Co-Authors: Roman Davydov, Mikhail Laryukhin, Amy Ledbetterrogers, Masanori Sono, John H Dawson, Brian M HoffmanAbstract:The fleeting ferric peroxo and hydroperoxo intermediates of dioxygen activation by Hemoproteins can be readily trapped and characterized during cryoradiolytic reduction of ferrous hemoprotein–O2 complexes at 77 K. Previous cryoannealing studies suggested that the relaxation of cryogenerated hydroperoxoferric intermediates of myoglobin (Mb), hemoglobin, and horseradish peroxidase (HRP), either trapped directly at 77 K or generated by cryoannealing of a trapped peroxo-ferric state, proceeds through dissociation of bound H2O2 and formation of the ferric heme without formation of the ferryl porphyrin π-cation radical intermediate, compound I (Cpd I). Herein we have reinvestigated the mechanism of decays of the cryogenerated hydroperoxyferric intermediates of α- and β-chains of human hemoglobin, HRP, and chloroperoxidase (CPO). The latter two proteins are well-known to form spectroscopically detectable quasistable Cpds I. Peroxoferric intermediates are trapped during 77 K cryoreduction of oxy Mb, α-chains, and...
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epr and endor studies of fe ii Hemoproteins reduced and oxidized at 77 k
Journal of Biological Inorganic Chemistry, 2008Co-Authors: Roman Davydov, Brian M HoffmanAbstract:γ-irradiation of frozen solutions of Fe(II) Hemoproteins at 77 K generates both electron paramagnetic resonance (EPR) active singly reduced and oxidized heme centers trapped in the conformation of the Fe(II) precursors. The reduction products of pentacoordinate (S = 2) Fe(II) globins, peroxidases and cytochrome P450cam show EPR and electron–nuclear double resonance (ENDOR) spectra characteristic of (3d7) Fe(I) species. In addition, cryoreduced Fe(II) α-chains of hemoglobin and myoglobin exhibit an S = 3/2 spin state produced by antiferromagnetic coupling between a porphyrin anion radical and pentacoordinate (S = 2) Fe(II). The spectra of cryoreduced forms of Fe(II) hemoglobin α-chains and deoxymyoglobin reveal that the Fe(II) precursors adopt multiple conformational substates. Reduction of hexacoordinate Fe(II) cytochrome c and cytochrome b5 as well as carboxy complexes of deoxyglobins produces only Fe(II) porphyrin π-anion radical species. The low-valent hemoprotein intermediates produced by cryoreduction convert to the Fe(II) states at T > 200 K. Cryogenerated Fe(III) cytochrome c and cytochrome b5 have spectra similar to these for the resting Fe(III) states, whereas the spectra of the products of cryooxidation of pentacoordinate Fe(II) globins and peroxidases are different. Cryooxidation of CO–Fe(II) globins generates Fe(III) hemes with quantum-mechanically admixed S = 3/2, 5/2 ground states. The trapped Fe(III) species relax to the equilibrium ferric states upon annealing at T > 190 K. Both cryooxidized and reduced centers provide very sensitive EPR/ENDOR structure probes of the EPR-silent Fe(II) state.
Alan R Brash - One of the best experts on this subject based on the ideXlab platform.
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Oxidation of C18 Hydroxy-Polyunsaturated Fatty Acids to Epoxide or Ketone by Catalase-Related Hemoproteins Activated with Iodosylbenzene
Lipids, 2017Co-Authors: Tarvi Teder, William E Boeglin, Alan R BrashAbstract:Small catalase-related Hemoproteins with a facility to react with fatty acid hydroperoxides were examined for their potential mono-oxygenase activity when activated using iodosylbenzene. The proteins tested were a Fusarium graminearum 41 kD catalase hemoprotein (Fg-cat, gene FGSG_02217), a Pseudomonas fluorescens Pfl01 catalase (37.5 kD, accession number WP_011333788.1), and a Mycobacterium avium ssp. paratuberculosis 33 kD catalase (gene MAP-2744c). 13-Hydroxy-octadecenoic acids (which are normally unreactive) were selected as substrates because these enzymes react specifically with the corresponding 13 S -hydroperoxides (Pakhomova et al . 18:2559–2568, 5 ; Teder et al . 1862:706–715, 14 ). In the presence of iodosylbenzene Fg-cat converted 13 S -hydroxy-fatty acids to two products: the 15,16-double bond of 13 S -hydroxy α-linolenic acid was oxidized stereospecifically to the 15 S ,16 R - cis -epoxide or the 13-hydroxyl was oxidized to the 13-ketone. Products were identified by UV, HPLC, LC–MS, NMR and by comparison with authentic standards prepared for this study. The Pfl01-cat displayed similar activity. MAP-2744c oxidized 13 S -hydroxy-linoleic acid to the 13-ketone, and epoxidized the double bonds to form the 9,10-epoxy-13-hydroxy, 11,12-epoxy-13-hydroxy, and 9,10-epoxy-13-keto derivatives; equivalent transformations occurred with 9 S -hydroxy-linoleic acid as substrate. In parallel incubations in the presence of iodosylbenzene, human catalase displayed no activity towards 13 S -hydroxy-linoleic acid, as expected from the highly restricted access to its active site. The results indicated that with suitable transformation to Compound I, monooxygenase activity can be demonstrated by these catalase-related Hemoproteins with tyrosine as the proximal heme ligand.
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cytochrome p450 type hydroxylation and epoxidation in a tyrosine liganded hemoprotein catalase related allene oxide synthase
Journal of Biological Chemistry, 2012Co-Authors: William E Boeglin, Alan R BrashAbstract:Abstract The ability of Hemoproteins to catalyze epoxidation or hydroxylation reactions is usually associated with a cysteine as the proximal ligand to the heme, as in cytochrome P450 or nitric oxide synthase. Catalase-related allene oxide synthase (cAOS) from the coral Plexaura homomalla, like catalase itself, has tyrosine as the proximal heme ligand. Its natural reaction is to convert 8R-hydroperoxy-eicosatetraenoic acid (8R-HPETE) to an allene epoxide, a reaction activated by the ferric heme, and forming product via the FeIV-OH intermediate, Compound II. Here we oxidized cAOS to Compound I (FeV=O) using the oxygen donor iodosylbenzene and investigated the catalytic competence of the enzyme. 8R-HETE, the hydroxy analog of the natural substrate, normally unreactive with cAOS, was thereby epoxidized stereopecifically on the 9,10 double bond to form 8R-hydroxy-9R,10R-trans-epoxy-eicosa-5Z,11Z,14Z-trienoic acid as the predominant product; the turnover was 1/s using 100 μM iodosylbenzene. The enantiomer, 8S-HETE, was epoxidized stereospecifically, although with less regiospecificity, and was hydroxylated on the 13- and 16-carbons. Arachidonic acid was converted to two major products, 8R-HETE and 8R,9S-eicosatrieneoic acid (8R,9S-EET), plus other chiral mono-epoxides and bis-allylic 10S-HETE. Linoleic acid was epoxidized, whereas stearic acid was not metabolized. We conclude that when cAOS is charged with an oxygen donor, it can act as a stereospecific monooxygenase. Our results indicate that in the tyrosine-liganded cAOS, a catalase-related hemoprotein in which a polyunsaturated fatty acid can enter the active site, the enzyme has the potential to mimic the activities of typical P450 epoxygenases and some capabilities of P450 hydroxylases.