1
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Li RJ, Tian K, Li X, Gaikaiwari AR, Li Z. Engineering P450 Monooxygenases for Highly Regioselective and Active p-Hydroxylation of m-Alkylphenols. ACS Catal 2022. [DOI: 10.1021/acscatal.1c06011] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Ren-Jie Li
- Department of Chemical and Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, Singapore 117585, Singapore
- Synthetic Biology for Clinical and Technological Innovation (SynCTI), National University of Singapore, 28 Medical Drive, Singapore 117456, Singapore
| | - Kaiyuan Tian
- Department of Chemical and Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, Singapore 117585, Singapore
| | - Xirui Li
- Department of Chemical and Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, Singapore 117585, Singapore
| | - Anand Raghavendra Gaikaiwari
- Department of Chemical and Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, Singapore 117585, Singapore
| | - Zhi Li
- Department of Chemical and Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, Singapore 117585, Singapore
- Synthetic Biology for Clinical and Technological Innovation (SynCTI), National University of Singapore, 28 Medical Drive, Singapore 117456, Singapore
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2
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Coleman T, Kirk AM, Lee JHZ, Doherty DZ, Bruning JB, Krenske EH, De Voss JJ, Bell SG. Different Geometric Requirements for Cytochrome P450-Catalyzed Aliphatic Versus Aromatic Hydroxylation Results in Chemoselective Oxidation. ACS Catal 2022. [DOI: 10.1021/acscatal.1c05483] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Tom Coleman
- Department of Chemistry, University of Adelaide, Adelaide, South Australia 5005, Australia
| | - Alicia M. Kirk
- School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane, Queensland 4072, Australia
| | - Joel H. Z. Lee
- Department of Chemistry, University of Adelaide, Adelaide, South Australia 5005, Australia
| | - Daniel Z. Doherty
- Department of Chemistry, University of Adelaide, Adelaide, South Australia 5005, Australia
| | - John B. Bruning
- School of Biological Sciences, University of Adelaide, Adelaide, South Australia 5005, Australia
| | - Elizabeth H. Krenske
- School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane, Queensland 4072, Australia
| | - James J. De Voss
- School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane, Queensland 4072, Australia
| | - Stephen G. Bell
- Department of Chemistry, University of Adelaide, Adelaide, South Australia 5005, Australia
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3
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Coleman T, Stok JE, Podgorski MN, Bruning JB, De Voss JJ, Bell SG. Structural insights into the role of the acid-alcohol pair of residues required for dioxygen activation in cytochrome P450 enzymes. J Biol Inorg Chem 2020; 25:583-596. [PMID: 32248305 DOI: 10.1007/s00775-020-01781-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Accepted: 03/22/2020] [Indexed: 10/24/2022]
Abstract
The cytochrome P450 heme monooxygenases commonly use an acid-alcohol pair of residues, within the I-helix, to activate iron-bound dioxygen. This work aims to clarify conflicting reports on the importance of the alcohol functionality in this process. Mutants of the P450, CYP199A4 (CYP199A4D251N and CYP199A4T252A), were prepared, characterised and their crystal structures were solved. The acid residue of CYP199A4 is not part of a salt bridge network, a key feature of paradigmatic model system P450cam. Instead, there is a direct proton delivery network, via a chain of water molecules, extending to the surface. Nevertheless, CYP199A4D251N dramatically reduced the activity of the enzyme consistent with a role in proton delivery. CYP199A4T252A decreased the coupling efficiency of the enzyme with a concomitant increase in the hydrogen peroxide uncoupling pathway. However, the effect of this mutation was much less pronounced than reported with P450cam. Its crystal structures revealed fewer changes at the I-helix, compared to the P450cam system. The structural changes observed within the I-helix of P450cam during oxygen activation do not seem to be required in this P450. These differences are due to the presence of a second threonine residue at position 253, which is absent in P450cam. This threonine forms part of the hydrogen bonding network, resulting in subtle structural changes and is also present across the majority of the P450 superfamily. Overall, the results suggest that while the acid-alcohol pair is important for dioxygen activation this process and the method of proton delivery can differ across P450s.Graphic abstract.
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Affiliation(s)
- Tom Coleman
- Department of Chemistry, University of Adelaide, Adelaide, SA, 5005, Australia
| | - Jeanette E Stok
- School of Chemistry and Molecular Bioscience, University of Queensland, Brisbane, QLD, 4072, Australia
| | - Matthew N Podgorski
- Department of Chemistry, University of Adelaide, Adelaide, SA, 5005, Australia
| | - John B Bruning
- School of Biological Sciences, University of Adelaide, Adelaide, SA, 5005, Australia
| | - James J De Voss
- School of Chemistry and Molecular Bioscience, University of Queensland, Brisbane, QLD, 4072, Australia
| | - Stephen G Bell
- Department of Chemistry, University of Adelaide, Adelaide, SA, 5005, Australia.
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4
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Bokel A, Rühlmann A, Hutter MC, Urlacher VB. Enzyme-Mediated Two-Step Regio- and Stereoselective Synthesis of Potential Rapid-Acting Antidepressant (2S,6S)-Hydroxynorketamine. ACS Catal 2020. [DOI: 10.1021/acscatal.9b05384] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Ansgar Bokel
- Institute of Biochemistry, Heinrich Heine University Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany
| | - Ansgar Rühlmann
- Institute of Biochemistry, Heinrich Heine University Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany
| | - Michael C. Hutter
- Center for Bioinformatics, Saarland University, Campus E2.1, 66123 Saarbruecken, Germany
| | - Vlada B. Urlacher
- Institute of Biochemistry, Heinrich Heine University Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany
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5
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Selective hydroxylation of 1,8- and 1,4-cineole using bacterial P450 variants. Arch Biochem Biophys 2019; 663:54-63. [DOI: 10.1016/j.abb.2018.12.025] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Revised: 10/24/2018] [Accepted: 12/21/2018] [Indexed: 01/10/2023]
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6
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Coleman T, Wong SH, Podgorski MN, Bruning JB, De Voss JJ, Bell SG. Cytochrome P450 CYP199A4 from Rhodopseudomonas palustris Catalyzes Heteroatom Dealkylations, Sulfoxidation, and Amide and Cyclic Hemiacetal Formation. ACS Catal 2018. [DOI: 10.1021/acscatal.8b00909] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Tom Coleman
- Department of Chemistry, University of Adelaide, Adelaide, SA 5005, Australia
| | - Siew Hoon Wong
- School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane, Qld 4072, Australia
| | | | - John B. Bruning
- School of Biological Sciences, University of Adelaide, Adelaide, SA 5005, Australia
| | - James J. De Voss
- School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane, Qld 4072, Australia
| | - Stephen G. Bell
- Department of Chemistry, University of Adelaide, Adelaide, SA 5005, Australia
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7
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Stereoselective hydroxylation of isophorone by variants of the cytochromes P450 CYP102A1 and CYP101A1. Enzyme Microb Technol 2018; 111:29-37. [PMID: 29421034 DOI: 10.1016/j.enzmictec.2018.01.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2017] [Revised: 01/02/2018] [Accepted: 01/04/2018] [Indexed: 11/23/2022]
Abstract
The stereoselective oxidation of hydrocarbons is an area of research where enzyme biocatalysis can make a substantial impact. The cyclic ketone isophorone was stereoselectively hydroxylated (≥95%) by wild-type CYP102A1 to form (R)-4-hydroxyisophorone, an important chiral synthon and flavour and fragrance compound. CYP102A1 variants were also selective for 4-hydroxyisophorone formation and the product formation rate increased over the wild-type enzyme by up to 285-fold, with the best mutants being R47L/Y51F/I401P and A74G/F87V/L188Q. The latter variant, which contained mutations in the distal substrate binding pocket, was marginally less selective. Combining perfluorodecanoic acid decoy molecules with the rate accelerating variant R47L/Y51F/I401P engendered further improvement with the purified enzymes. However when the decoy molecules were used with A74G/F87V/L188Q the amount of product generated by the enzyme was reduced. Addition of decoy molecules to whole-cell turnovers did not improve the productivity of these CYP102A1 systems. WT CYP101A1 formed significant levels of 7-hydroxyisophorone as a minor product alongside 4-hydroxyisophorone. However the F87W/Y96F/L244A/V247L CYP101A1 mutant was ≥98% selective for (R)-4-hydroxyisophorone. A comparison of the two enzyme systems using whole-cell oxidation reactions showed that the best CYP101A1 variant was able to generate more product. We also characterised that the further oxidation metabolite 4-ketoisophorone was produced and then subsequently reduced to levodione by an endogenous Escherichia coli ene reductase.
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8
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Kammoonah S, Prasad B, Balaraman P, Mundhada H, Schwaneberg U, Plettner E. Selecting of a cytochrome P450 cam SeSaM library with 3-chloroindole and endosulfan - Identification of mutants that dehalogenate 3-chloroindole. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2017; 1866:68-79. [PMID: 28923662 DOI: 10.1016/j.bbapap.2017.09.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2017] [Revised: 09/12/2017] [Accepted: 09/14/2017] [Indexed: 11/25/2022]
Abstract
Cytochrome P450cam (a camphor hydroxylase) from the soil bacterium Pseudomonas putida shows potential importance in environmental applications such as the degradation of chlorinated organic pollutants. Seven P450cam mutants generated from Sequence Saturation Mutagenesis (SeSaM) and isolated by selection on minimal media with either 3-chloroindole or the insecticide endosulfan were studied for their ability to oxidize of 3-chloroindole to isatin. The wild-type enzyme did not accept 3-chloroindole as a substrate. Mutant (E156G/V247F/V253G/F256S) had the highest maximal velocity in the conversion of 3-chloroindole to isatin, whereas mutants (T56A/N116H/D297N) and (G60S/Y75H) had highest kcat/KM values. Six of the mutants had more than one mutation, and within this set, mutation of residues 297 and 179 was observed twice. Docking simulations were performed on models of the mutant enzymes; the wild-type did not accommodate 3-chloroindole in the active site, whereas all the mutants did. We propose two potential reaction pathways for dechlorination of 3-chloroindole. This article is part of a Special Issue entitled: Cytochrome P450 biodiversity and biotechnology, edited by Erika Plettner, Gianfranco Gilardi, Luet Wong, Vlada Urlacher, Jared Goldstone.
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Affiliation(s)
- Shaima Kammoonah
- Department of Chemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada
| | - Brinda Prasad
- Department of Chemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada
| | - Priyadarshini Balaraman
- Department of Chemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada
| | - Hemanshu Mundhada
- Institute of Biotechnology, RWTH Aachen University, Worringer Weg 3, 52074 Aachen, Germany
| | - Ulrich Schwaneberg
- Institute of Biotechnology, RWTH Aachen University, Worringer Weg 3, 52074 Aachen, Germany
| | - Erika Plettner
- Department of Chemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada.
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9
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Hall EA, Sarkar MR, Bell SG. The selective oxidation of substituted aromatic hydrocarbons and the observation of uncoupling via redox cycling during naphthalene oxidation by the CYP101B1 system. Catal Sci Technol 2017. [DOI: 10.1039/c7cy00088j] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Oxidation of polyaromatic hydrocarbons by P450s can be lowered by redox cycling but CYP101B1 regioselectively hydroxylated substituted naphthalenes and biphenyls.
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Affiliation(s)
- Emma A. Hall
- Department of Chemistry
- University of Adelaide
- Australia
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10
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Chao RR, Lau ICK, De Voss JJ, Bell SG. Modification of an Enzyme Biocatalyst for the Efficient and Selective Oxidative Demethylation ofpara-Substituted Benzene Derivatives. ChemCatChem 2016. [DOI: 10.1002/cctc.201600951] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Rebecca R. Chao
- Department of Chemistry; University Adelaide; Adelaide SA 5005 Australia
| | - Ian C.-K. Lau
- Department of Chemistry; University Adelaide; Adelaide SA 5005 Australia
| | - James J. De Voss
- School of Chemistry and Molecular Bioscience; University of Queensland; St Lucia Qld 4072 Australia
| | - Stephen G. Bell
- Department of Chemistry; University Adelaide; Adelaide SA 5005 Australia
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11
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Colthart AM, Tietz DR, Ni Y, Friedman JL, Dang M, Pochapsky TC. Detection of substrate-dependent conformational changes in the P450 fold by nuclear magnetic resonance. Sci Rep 2016; 6:22035. [PMID: 26911901 PMCID: PMC4766564 DOI: 10.1038/srep22035] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Accepted: 02/03/2016] [Indexed: 01/23/2023] Open
Abstract
Cytochrome P450 monooxygenases typically catalyze the insertion of one atom of oxygen from O2 into unactivated carbon-hydrogen and carbon-carbon bonds, with concomitant reduction of the other oxygen atom to H2O by NAD(P)H. Comparison of the average structures of the camphor hydroxylase cytochrome P450(cam) (CYP101) obtained from residual dipolar coupling (RDC)-restrained molecular dynamics (MD) in the presence and absence of substrate camphor shows structural displacements resulting from the essential collapse of the active site upon substrate removal. This collapse has conformational consequences that extend across the protein structure, none of which were observed in analogous crystallographic structures. Mutations were made to test the involvement of the observed conformational changes in substrate binding and recognition. All of the mutations performed based upon the NMR-detected perturbations, even those remote from the active site, resulted in modified substrate selectivity, enzyme efficiency and/or haem iron spin state. The results demonstrate that solution NMR can provide insights into enzyme structure-function relationships that are difficult to obtain by other methods.
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Affiliation(s)
- Allison M. Colthart
- Departments of Chemistry and Biochemistry Brandeis University, 415 South St., Waltham MA 02454-9110, USA
| | - Drew R. Tietz
- Departments of Chemistry and Biochemistry Brandeis University, 415 South St., Waltham MA 02454-9110, USA
| | - Yuhua Ni
- Departments of Chemistry and Biochemistry Brandeis University, 415 South St., Waltham MA 02454-9110, USA
| | - Jessica L. Friedman
- Departments of Chemistry and Biochemistry Brandeis University, 415 South St., Waltham MA 02454-9110, USA
| | - Marina Dang
- Departments of Chemistry and Biochemistry Brandeis University, 415 South St., Waltham MA 02454-9110, USA
| | - Thomas C. Pochapsky
- Departments of Chemistry and Biochemistry Brandeis University, 415 South St., Waltham MA 02454-9110, USA
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12
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Coleman T, Chao RR, Bruning JB, De Voss JJ, Bell SG. CYP199A4 catalyses the efficient demethylation and demethenylation of para-substituted benzoic acid derivatives. RSC Adv 2015. [DOI: 10.1039/c5ra08730a] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
CYP199A4, a cytochrome P450 enzyme from Rhodopseudomonas palustris HaA2, is able to efficiently demethylate a range of benzoic acids at the para-position. It can also catalyse demethenylation reactions.
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Affiliation(s)
- Tom Coleman
- Department of Chemistry
- University of Adelaide
- Australia
| | | | - John B. Bruning
- Department of Molecular and Cellular Biology
- University of Adelaide
- Adelaide
- Australia
| | - James J. De Voss
- School of Chemistry and Molecular Biosciences
- University of Queensland
- Brisbane
- Australia
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13
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Bell SG, Spence JTJ, Liu S, George JH, Wong LL. Selective aliphatic carbon–hydrogen bond activation of protected alcohol substrates by cytochrome P450 enzymes. Org Biomol Chem 2014; 12:2479-88. [DOI: 10.1039/c3ob42417k] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Protected cyclohexanol and cyclohex-2-enol substrates were efficiently and selectively oxidised by different P450cam mutants providing a general methodology for generating substituted diols using biocatalysts.
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Affiliation(s)
- Stephen G. Bell
- School of Chemistry and Physics
- University of Adelaide
- , Australia
- Department of Chemistry
- University of Oxford
| | | | - Shenglan Liu
- School of Chemistry and Physics
- University of Adelaide
- , Australia
| | | | - Luet-Lok Wong
- Department of Chemistry
- University of Oxford
- Inorganic Chemistry Laboratory
- Oxford, UK
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14
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Biocatalytic production of 5-hydroxy-2-adamantanone by P450cam coupled with NADH regeneration. ACTA ACUST UNITED AC 2013. [DOI: 10.1016/j.molcatb.2013.05.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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15
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Rabe KS, Niemeyer CM. Screening for cytochrome P450 reactivity with a reporter enzyme. METHODS IN MOLECULAR BIOLOGY (CLIFTON, N.J.) 2013; 987:149-56. [PMID: 23475675 DOI: 10.1007/978-1-62703-321-3_13] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The identification of novel substrates of cytochrome P450 enzymes by high-throughput screening assays is of utmost importance to further increase the scope of these enzymes for future applications. Most screens are either confined to individual substrate analogues or hampered by low throughput due to elaborate analysis techniques. Here we describe a general high-throughput screening assay that interrogates the activity of P450 enzymes with the aid of catalase as a reporter enzyme.
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Affiliation(s)
- Kersten S Rabe
- Fakultät Chemie, Biologisch-Chemische Mikrostrukturtechnik, Technische Universität Dortmund, Dortmund, Germany
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16
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Butler CF, Peet C, Mason AE, Voice MW, Leys D, Munro AW. Key mutations alter the cytochrome P450 BM3 conformational landscape and remove inherent substrate bias. J Biol Chem 2013; 288:25387-25399. [PMID: 23828198 DOI: 10.1074/jbc.m113.479717] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Cytochrome P450 monooxygenases (P450s) have enormous potential in the production of oxychemicals, due to their unparalleled regio- and stereoselectivity. The Bacillus megaterium P450 BM3 enzyme is a key model system, with several mutants (many distant from the active site) reported to alter substrate selectivity. It has the highest reported monooxygenase activity of the P450 enzymes, and this catalytic efficiency has inspired protein engineering to enable its exploitation for biotechnologically relevant oxidations with structurally diverse substrates. However, a structural rationale is lacking to explain how these mutations have such effects in the absence of direct change to the active site architecture. Here, we provide the first crystal structures of BM3 mutants in complex with a human drug substrate, the proton pump inhibitor omeprazole. Supported by solution data, these structures reveal how mutation alters the conformational landscape and decreases the free energy barrier for transition to the substrate-bound state. Our data point to the importance of such "gatekeeper" mutations in enabling major changes in substrate recognition. We further demonstrate that these mutants catalyze the same 5-hydroxylation reaction as performed by human CYP2C19, the major human omeprazole-metabolizing P450 enzyme.
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Affiliation(s)
- Christopher F Butler
- From the Manchester Institute of Biotechnology, Faculty of Life Sciences, University of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom and
| | - Caroline Peet
- Cypex Ltd., 6 Tom McDonald Avenue, Dundee DD2 1NH, Scotland, United Kingdom
| | - Amy E Mason
- From the Manchester Institute of Biotechnology, Faculty of Life Sciences, University of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom and
| | - Michael W Voice
- Cypex Ltd., 6 Tom McDonald Avenue, Dundee DD2 1NH, Scotland, United Kingdom
| | - David Leys
- From the Manchester Institute of Biotechnology, Faculty of Life Sciences, University of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom and
| | - Andrew W Munro
- From the Manchester Institute of Biotechnology, Faculty of Life Sciences, University of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom and.
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17
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Igbinosa EO, Odjadjare EE, Chigor VN, Igbinosa IH, Emoghene AO, Ekhaise FO, Igiehon NO, Idemudia OG. Toxicological profile of chlorophenols and their derivatives in the environment: the public health perspective. ScientificWorldJournal 2013; 2013:460215. [PMID: 23690744 PMCID: PMC3649668 DOI: 10.1155/2013/460215] [Citation(s) in RCA: 128] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2013] [Accepted: 03/06/2013] [Indexed: 11/18/2022] Open
Abstract
Chlorophenol compounds and their derivatives are ubiquitous contaminants in the environment. These compounds are used as intermediates in manufacturing agricultural chemicals, pharmaceuticals, biocides, and dyes. Chlorophenols gets into the environment from a variety of sources such as industrial waste, pesticides, and insecticides, or by degradation of complex chlorinated hydrocarbons. Thermal and chemical degradation of chlorophenols leads to the formation of harmful substances which constitute public health problems. These compounds may cause histopathological alterations, genotoxicity, mutagenicity, and carcinogenicity amongst other abnormalities in humans and animals. Furthermore, the recalcitrant nature of chlorophenolic compounds to degradation constitutes an environmental nuisance, and a good understanding of the fate and transport of these compounds and their derivatives is needed for a clearer view of the associated risks and mechanisms of pathogenicity to humans and animals. This review looks at chlorophenols and their derivatives, explores current research on their effects on public health, and proffers measures for mitigation.
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Affiliation(s)
- Etinosa O Igbinosa
- Department of Microbiology, Faculty of Life Sciences, University of Benin, PMB 1154, Benin City, Nigeria.
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18
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Hoffmann G, Bönsch K, Greiner-Stöffele T, Ballschmiter M. Changing the substrate specificity of P450cam towards diphenylmethane by semi-rational enzyme engineering. Protein Eng Des Sel 2011; 24:439-46. [PMID: 21273340 DOI: 10.1093/protein/gzq119] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
A focused library comprising nine residues of the active site of P450cam monooxygenase resulting in ∼ 300,000 protein variants was screened for activity on diphenylmethane (DPM). The assay was based on the depletion of NADH by an in vitro reconstituted P450cam system in a 96-well scale. The throughput was increased by the parallel cultivation, purification and analysis of 20 variants per well (cluster screening). Thus ∼ 20,000 protein variants could be screened in summary of which five were found to transform DPM with a specific activity of up to 75% of the wild-type activity on d-camphor and a coupling rate of 7-18%. One variant converting DPM to 4-hydroxydiphenylmethane (4HDPM) was subjected to site-directed mutagenesis and saturation mutagenesis, which revealed the particular importance of positions F87, Y96 and L244 for substrate selectivity and the possibility for further improvements of this variant. Moreover, a reduction in size of the amino acid at position 396 decreased specific activity dramatically but increased coupling and switched the main product formation from 4HDPM towards diphenylmethanol.
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Affiliation(s)
- Gregor Hoffmann
- Institute of Biochemistry, University of Leipzig, Deutscher Platz 5b, 04103 Leipzig, Germany
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19
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Whitehouse CJC, Yang W, Yorke JA, Tufton HG, Ogilvie LCI, Bell SG, Zhou W, Bartlam M, Rao Z, Wong LL. Structure, electronic properties and catalytic behaviour of an activity-enhancing CYP102A1 (P450BM3) variant. Dalton Trans 2011; 40:10383-96. [DOI: 10.1039/c1dt10098j] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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20
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Expression, purification and characterization of two Clostridium acetobutylicum flavodoxins: Potential electron transfer partners for CYP152A2. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2011; 1814:257-64. [DOI: 10.1016/j.bbapap.2010.06.013] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2010] [Revised: 06/10/2010] [Accepted: 06/17/2010] [Indexed: 11/18/2022]
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21
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Furuya T, Kino K. Genome mining approach for the discovery of novel cytochrome P450 biocatalysts. Appl Microbiol Biotechnol 2010; 86:991-1002. [DOI: 10.1007/s00253-010-2450-5] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2009] [Revised: 01/13/2010] [Accepted: 01/13/2010] [Indexed: 10/19/2022]
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22
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Manna SK, Mazumdar S. Tuning the substrate specificity by engineering the active site of cytochrome P450cam: a rational approach. Dalton Trans 2010; 39:3115-23. [PMID: 20221546 DOI: 10.1039/b922885c] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Rational design of the active site of cytochrome P450cam has been carried out to catalyse oxygenation of various potentially important chemical reactions. The modeling studies showed that the distal pocket of the heme consisting of the Y96, T101, F87 and L244 residues could be suitably mutated to change the substrate specificity of the enzyme. We found that the mutant enzymes could catalyse oxygenation of indole to produce indigo. While Y96F was found to be several times better as a catalyst for conversion of indole to indigo, the double mutant Y96F/L244A showed the highest NADH oxidation rate as well as yield of indigo. The oxidative catalysis using H(2)O(2) as the oxygen source was found to produce a higher purity of indigo, and lesser or no formation of indirubin was detected. The enzymatic oxygenation of aromatic hydrocarbons such as coumarin and analogues was also found to be enhanced on mutation of Y96 and L244 residues in the enzyme. The studies also showed that mutation of suitable residues can alter the regio-selectivity of hydroxylation of the aromatic hydrocarbons.
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Affiliation(s)
- Soumen Kanti Manna
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400 005, India
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Michałowicz J. Pentachlorophenol and its derivatives induce oxidative damage and morphological changes in human lymphocytes (in vitro). Arch Toxicol 2010; 84:379-87. [PMID: 20127076 DOI: 10.1007/s00204-010-0515-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2009] [Accepted: 01/14/2010] [Indexed: 11/28/2022]
Abstract
In this study, the effect of environmental toxins such as pentachlorophenol (PCP), tetrachlorocatechol (TeCC) and tetrachloroguaiacol (TeCG) on human peripheral blood lymphocytes was investigated. All the compounds studied increased the size and granularity of the lymphocytes in the concentrations range from 5 to 600 ppm. The PCP caused the strongest increase in the size of the cells, whereas lymphocytes granularity was more strongly increased by TeCC and PCP than by TeCG. The PCP and its derivatives in the concentrations range from 1 to 125 ppm significantly depleted ATP level. It was also observed that PCP most strongly decreased ATP content at its highest concentration of 125 ppm. Moreover, PCP caused the highest loss of lymphocytes viability in the concentrations range from 125 to 600 ppm. The TeCC in the concentrations of 1 and 5 ppm significantly increased the level of strand breaks in DNA, whereas lower damage was noted for PCP, and particularly for TeCG. The increase in carbonyl groups content was more strongly induced by TeCG and TeCC than by PCP in the concentrations range from 0.04 to 1 ppm; however, in a concentration of 5 ppm, all the compounds studied increased this parameter to a similar degree. DNA and protein damage was the most probably induced by free radical formation, as it was observed that all the compounds examined, and TeCC, in particular, were able of oxidize a fluorescent probe 6-carboxy-2',7'-dichlorodihydrofluorescein in the concentrations range from 0.01 to 1 ppm.
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Affiliation(s)
- Jaromir Michałowicz
- Department of Environmental Pollution Biophysics, University of Łódź, Banacha 12/16 St., 90-237 Łódź, Poland.
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Michałowicz J, Majsterek I. Chlorophenols, chlorocatechols and chloroguaiacols induce DNA base oxidation in human lymphocytes (in vitro). Toxicology 2009; 268:171-5. [PMID: 20025924 DOI: 10.1016/j.tox.2009.12.009] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2009] [Revised: 12/08/2009] [Accepted: 12/09/2009] [Indexed: 11/27/2022]
Abstract
Phenolic compounds are strong environmental toxicants, which are found in food, drinking water as well as in the indoor and outdoor air environment. In this work we investigated the effect of low concentrations of 0.2, 1 and 5 microg/ml of 2,4,5-trichlorophenol (2,4,5-TCP), pentachlorophenol (PCP), 4,6-dichloroguaiacol (4,6-DCG), tetrachloroguaiacol (TeCG), 4,5-dichlorocatechol (4,5-DCC) and tetrachlorocatechol (TeCC) on DNA bases oxidation in human peripheral blood lymphocytes. The analysis was performed using alkaline single cell gel electrophoresis (the comet assay). To detect oxidized pyrimidynes and purines we used the repair enzymes such as endonuclease III and formamidopyrimidine-DNA glycosylase. DNA oxidation was expressed as a percentage of comet tail, which was formed after the xenobiotics treatment. The obtained results showed that all the compounds examined were able to oxidize DNA bases in human lymphocytes. It was also observed that pyrimidine bases were more strongly oxidized in comparison to purine ones. Finally, it was found that chlorinated catechols and TeCC in particular, revealed a higher oxidative potential in comparison to chlorophenols and chloroguaiacols, and a rise in the number of chlorine atoms in the compound from each group examined led to an increase in DNA bases damage.
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Affiliation(s)
- Jaromir Michałowicz
- Department of Environmental Pollution Biophysics, University of Łódź, Banacha 12/16 St., 90-237 Łódź, Poland.
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Michałowicz J, Sicińska P. Chlorophenols and chlorocatechols induce apoptosis in human lymphocytes (in vitro). Toxicol Lett 2009; 191:246-52. [DOI: 10.1016/j.toxlet.2009.09.010] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2009] [Revised: 09/09/2009] [Accepted: 09/10/2009] [Indexed: 11/27/2022]
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Spectroscopic studies of the oxidation of ferric CYP153A6 by peracids: Insights into P450 higher oxidation states. Arch Biochem Biophys 2009; 493:184-91. [PMID: 19879854 DOI: 10.1016/j.abb.2009.10.014] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2009] [Revised: 10/25/2009] [Accepted: 10/27/2009] [Indexed: 11/21/2022]
Abstract
Our previous rapid-scanning stopped-flow studies of the reaction of substrate-free cytochrome P450cam with peracids [T. Spolitak, J.H. Dawson, D.P. Ballou, J. Biol. Chem. 280 (2005) 20300-20309; J. Inorg. Biochem. 100 (2006) 2034-2044; J. Biol. Inorg. Chem. 13 (2008) 599-611] spectrally characterized compound I (ferryl iron plus a porphyrin pi-cation radical (Fe(IV)O/Por(.+))), Cpd ES, and Cpd II (Fe(IV)O/Tyr() or Fe(IV)O). We now report that reactions of CYP153A6 with peracids yield all these intermediates, with kinetic profiles allowing better resolution of all forms at pH 8.0 compared to similar reactions with WT P450cam. Properties of the reactions of these higher oxidation state intermediates were determined in double-mixing experiments in which intermediates are pre-formed and ascorbate is then added. Reactions of heptane-bound CYP153A6 (pH 7.4) with mCPBA resulted in conversion of P450 to the low-spin ferric form, presumably as heptanol was formed, suggesting that CYP 153A6 is a potential biocatalyst that can use peracids with no added NAD(P)H or reducing systems for bioremediation and other industrial applications.
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Rabe KS, Spengler M, Erkelenz M, Müller J, Gandubert VJ, Hayen H, Niemeyer CM. Screening for cytochrome p450 reactivity by harnessing catalase as reporter enzyme. Chembiochem 2009; 10:751-7. [PMID: 19241405 DOI: 10.1002/cbic.200800750] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Cytochrome P450 enzymes are known to catalyze a variety of reactions that are difficult to perform by standard organic synthesis, such as the oxidation of unactivated C--C bonds. Cytochrome P450 enzymes can also be used in artificial systems in which organic peroxides act as cosubstrates. To find substrates that are converted by a certain P450 catalyst in the presence of an organic peroxide, various screening assays have been established, however, most of them are limited to one or only a few specific substrates. Here, we report a simple and rapid screening assay that works independently of the nature of the substrate and utilizes a previously undescribed reactivity of catalase as reporter enzyme. In an initial demonstration of this assay, we screened 180 enzyme/peroxide/substrate combinations for potential bioconversions. As shown by subsequent verification of the screening results with liquid chromatography/multistage mass spectrometry (LC/MS(n)), we were able to identify three new substrates for the enzyme CYP152A1 and at least two previously undescribed conversions by the enzyme CYP119.
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Affiliation(s)
- Kersten S Rabe
- Technische Universität Dortmund, Fakultät Chemie, Biologisch-Chemische Mikrostrukturtechnik, Otto-Hahn Strasse 6, Dortmund, Germany
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Rabe KS, Gandubert VJ, Spengler M, Erkelenz M, Niemeyer CM. Engineering and assaying of cytochrome P450 biocatalysts. Anal Bioanal Chem 2008; 392:1059-73. [PMID: 18622752 DOI: 10.1007/s00216-008-2248-9] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2008] [Revised: 06/11/2008] [Accepted: 06/12/2008] [Indexed: 11/29/2022]
Abstract
Cytochrome P450s constitute a highly fascinating superfamily of enzymes which catalyze a broad range of reactions. They are essential for drug metabolism and promise industrial applications in biotechnology and biosensing. The constant search for cytochrome P450 enzymes with enhanced catalytic performances has generated a large body of research. This review will concentrate on two key aspects related to the identification and improvement of cytochrome P450 biocatalysts, namely the engineering and assaying of these enzymes. To this end, recent advances in cytochrome P450 development are reported and commonly used screening methods are surveyed.
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Affiliation(s)
- Kersten S Rabe
- Fakultät für Chemie, Biologisch-Chemische Mikrostrukturtechnik, Technische Universität Dortmund, Otto-Hahn-Strabetae 6, 44227, Dortmund, Germany
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