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Heterologous Expression of Recombinant Human Cytochrome P450 (CYP) in Escherichia coli: N-Terminal Modification, Expression, Isolation, Purification, and Reconstitution. BIOTECH 2023; 12:biotech12010017. [PMID: 36810444 PMCID: PMC9944785 DOI: 10.3390/biotech12010017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Revised: 02/02/2023] [Accepted: 02/03/2023] [Indexed: 02/10/2023] Open
Abstract
Cytochrome P450 (CYP) enzymes play important roles in metabolising endogenous and xenobiotic substances. Characterisations of human CYP proteins have been advanced with the rapid development of molecular technology that allows heterologous expression of human CYPs. Among several hosts, bacteria systems such as Escherichia coli (E. coli) have been widely used thanks to their ease of use, high level of protein yields, and affordable maintenance costs. However, the levels of expression in E. coli reported in the literature sometimes differ significantly. This paper aims to review several contributing factors, including N-terminal modifications, co-expression with a chaperon, selections of vectors and E. coli strains, bacteria culture and protein expression conditions, bacteria membrane preparations, CYP protein solubilizations, CYP protein purifications, and reconstitution of CYP catalytic systems. The common factors that would most likely lead to high expression of CYPs were identified and summarised. Nevertheless, each factor may still require careful evaluation for individual CYP isoforms to achieve a maximal expression level and catalytic activity. Recombinant E. coli systems have been evidenced as a useful tool in obtaining the ideal level of human CYP proteins, which ultimately allows for subsequent characterisations of structures and functions.
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Thomson RES, D'Cunha SA, Hayes MA, Gillam EMJ. Use of engineered cytochromes P450 for accelerating drug discovery and development. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2022; 95:195-252. [PMID: 35953156 DOI: 10.1016/bs.apha.2022.06.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Numerous steps in drug development, including the generation of authentic metabolites and late-stage functionalization of candidates, necessitate the modification of often complex molecules, such as natural products. While it can be challenging to make the required regio- and stereoselective alterations to a molecule using purely chemical catalysis, enzymes can introduce changes to complex molecules with a high degree of stereo- and regioselectivity. Cytochrome P450 enzymes are biocatalysts of unequalled versatility, capable of regio- and stereoselective functionalization of unactivated CH bonds by monooxygenation. Collectively they catalyze over 60 different biotransformations on structurally and functionally diverse organic molecules, including natural products, drugs, steroids, organic acids and other lipophilic molecules. This catalytic versatility and substrate range makes them likely candidates for application as potential biocatalysts for industrial chemistry. However, several aspects of the P450 catalytic cycle and other characteristics have limited their implementation to date in industry, including: their lability at elevated temperature, in the presence of solvents, and over lengthy incubation times; the typically low efficiency with which they metabolize non-natural substrates; and their lack of specificity for a single metabolic pathway. Protein engineering by rational design or directed evolution provides a way to engineer P450s for industrial use. Here we review the progress made to date toward engineering the properties of P450s, especially eukaryotic forms, for industrial application, and including the recent expansion of their catalytic repertoire to include non-natural reactions.
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Affiliation(s)
- Raine E S Thomson
- School of Chemistry & Molecular Biosciences, The University of Queensland, Brisbane, QLD, Australia
| | - Stephlina A D'Cunha
- School of Chemistry & Molecular Biosciences, The University of Queensland, Brisbane, QLD, Australia
| | - Martin A Hayes
- Compound Synthesis and Management, Discovery Sciences, BioPharmaceuticals R&D AstraZeneca, Mölndal, Sweden
| | - Elizabeth M J Gillam
- School of Chemistry & Molecular Biosciences, The University of Queensland, Brisbane, QLD, Australia.
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3
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Hoffmann SM, Weissenborn MJ, Gricman Ł, Notonier S, Pleiss J, Hauer B. The Impact of Linker Length on P450 Fusion Constructs: Activity, Stability and Coupling. ChemCatChem 2016. [DOI: 10.1002/cctc.201501397] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Sara M. Hoffmann
- Institute of Technical Biochemistry; University of Stuttgart; Allmandring 31 70569 Stuttgart Germany
| | - Martin J. Weissenborn
- Institute of Technical Biochemistry; University of Stuttgart; Allmandring 31 70569 Stuttgart Germany
| | - Łukasz Gricman
- Institute of Technical Biochemistry; University of Stuttgart; Allmandring 31 70569 Stuttgart Germany
| | - Sandra Notonier
- Institute of Technical Biochemistry; University of Stuttgart; Allmandring 31 70569 Stuttgart Germany
| | - Jürgen Pleiss
- Institute of Technical Biochemistry; University of Stuttgart; Allmandring 31 70569 Stuttgart Germany
| | - Bernhard Hauer
- Institute of Technical Biochemistry; University of Stuttgart; Allmandring 31 70569 Stuttgart Germany
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Sadeghi SJ, Gilardi G. Chimeric P450 enzymes: Activity of artificial redox fusions driven by different reductases for biotechnological applications. Biotechnol Appl Biochem 2013; 60:102-10. [DOI: 10.1002/bab.1086] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2012] [Accepted: 12/20/2012] [Indexed: 11/09/2022]
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5
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Kaspera R, Naraharisetti SB, Evangelista EA, Marciante KD, Psaty BM, Totah RA. Drug metabolism by CYP2C8.3 is determined by substrate dependent interactions with cytochrome P450 reductase and cytochrome b5. Biochem Pharmacol 2011; 82:681-91. [PMID: 21726541 DOI: 10.1016/j.bcp.2011.06.027] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2011] [Revised: 06/16/2011] [Accepted: 06/16/2011] [Indexed: 01/20/2023]
Abstract
Genetic polymorphisms in CYP2C8 can influence the metabolism of important therapeutic agents and cause interindividual variation in drug response and toxicity. The significance of the variant CYP2C8*3 has been controversial with reports of higher in vivo but lower in vitro activity compared to CYP2C8*1. In this study, the contribution of the redox partners cytochrome P450 reductase (CPR) and cytochrome b5 to the substrate dependent activity of CYP2C8.3 (R139K, K399R) was investigated in human liver microsomes (HLMs) and Escherichia coli expressed recombinant CYP2C8 proteins using amodiaquine, paclitaxel, rosiglitazone and cerivastatin as probe substrates. For recombinant CYP2C8.3, clearance values were two- to five-fold higher compared to CYP2C8.1. CYP2C8.3's higher k(cat) seems to be dominated by a higher, but substrate specific affinity, towards cytochrome b5 and CPR (K(D) and K(m,red)) which resulted in increased reaction coupling. A stronger binding affinity of ligands to CYP2C8.3, based on a two site binding model, in conjunction with a five fold increase in amplitude of heme spin change during binding of ligands and redox partners could potentially contribute to a higher k(cat). In HLMs, carriers of the CYP2C8*1/*3 genotype were as active as CYP2C8*1/*1 towards the CYP2C8 specific reaction amodiaquine N-deethylation. Large excess of cytochrome b5 compared to CYP2C8 in recombinant systems and HLMs inhibited metabolic clearance, diminishing the difference in k(cat) between the two enzymes, and may provide an explanation for the discrepancy to in vivo data. In silico studies illustrate the genetic differences between wild type and variant on the molecular level.
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Affiliation(s)
- Rüdiger Kaspera
- Department of Medicinal Chemistry, University of Washington, Seattle, WA 98195-7610, USA
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6
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Salamanca-Pinzón SG, Guengerich FP. A tricistronic human adrenodoxin reductase-adrenodoxin-cytochrome P450 27A1 vector system for substrate hydroxylation in Escherichia coli. Protein Expr Purif 2011; 79:231-6. [PMID: 21621619 DOI: 10.1016/j.pep.2011.05.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2011] [Revised: 05/11/2011] [Accepted: 05/12/2011] [Indexed: 01/01/2023]
Abstract
Cytochrome P450 (P450) 27A1 catalyzes 27-hydroxylation of cholesterol and 25-hydroxylation of vitamin D(3), serving as an important component for the maintenance of lipid homeostasis. In eukaryotic cells P450 27A1 is a membrane-bound protein located on the inner mitochondrial membrane and requires two auxiliary reduction partners, adrenodoxin (Adx) and NADPH-adrenodoxin reductase (Adr), for catalysis in the bile acid biosynthesis pathway. A strategy was developed for the functional coexpression of P450 27A1 with Adr and Adx in a tricistronic fashion (single RNA, three proteins) in Escherichia coli, mimicking the mitochondrial P450 system. Intact bacterial cells coexpressing the P450 vector (pTC27A1) efficiently hydroxylated cholesterol at the 27 position as well as vitamin D(3) at the 25 position when supplemented with glycerol as a carbon source. Thus, E. coli containing pTC27A1 is able to hydroxylate cholesterol in a self-sufficient fashion and is suitable for further applications of protein interaction, drug discovery, and inhibitor evaluation and for the study of other mitochondrial P450s and oxysterol production in microorganisms without a need for membrane reconstitution, membrane simulation by detergents, or purification of the components.
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Affiliation(s)
- S Giovanna Salamanca-Pinzón
- Department of Biochemistry and Center in Molecular Toxicology, Vanderbilt University School of Medicine, Nashville, TN 37232-0146, USA
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7
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Hlavica P. Assembly of non-natural electron transfer conduits in the cytochrome P450 system: A critical assessment and update of artificial redox constructs amenable to exploitation in biotechnological areas. Biotechnol Adv 2009; 27:103-21. [DOI: 10.1016/j.biotechadv.2008.10.001] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2008] [Revised: 09/29/2008] [Accepted: 10/04/2008] [Indexed: 10/21/2022]
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8
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Affiliation(s)
- Elizabeth M. J. Gillam
- School of Biomedical Sciences, The University of Queensland, St. Lucia, Brisbane, Australia 4072
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9
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McLean KJ, Girvan HM, Munro AW. Cytochrome P450/redox partner fusion enzymes: biotechnological and toxicological prospects. Expert Opin Drug Metab Toxicol 2007; 3:847-63. [PMID: 18028029 DOI: 10.1517/17425255.3.6.847] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Cytochromes P450 (CYPs) are versatile oxidase catalysts that play pivotal roles in drug metabolism. They are highly regarded as biotechnological tools for their capacity to perform regio- and stereo-selective oxidations. Human CYPs source electrons for oxygen activation from one or more separate redox partner enzymes. However, several CYP enzymes are now known in which the CYP is covalently linked to a reductase system. Some of these systems offer distinct advantages over typical CYPs as efficient, self-contained units capable of important biotransformations, including synthesis of high value chemicals and pharmaceuticals. Protein engineering has been widely applied to produce variant CYP fusions with desirable activities. The review focuses on the nature and diversity of CYP/redox partner fusion enzymes and their biocatalytic potential.
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Affiliation(s)
- Kirsty J McLean
- University of Manchester, Manchester Interdisciplinary Biocentre, Faculty of Life Sciences, 131 Princess Street, Manchester M1 7DN, UK
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10
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Dodhia VR, Fantuzzi A, Gilardi G. Engineering human cytochrome P450 enzymes into catalytically self-sufficient chimeras using molecular Lego. J Biol Inorg Chem 2006; 11:903-16. [PMID: 16862439 DOI: 10.1007/s00775-006-0144-3] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2006] [Accepted: 06/29/2006] [Indexed: 11/27/2022]
Abstract
The membrane-bound human cytochrome P450s have essential roles in the metabolism of endogenous compounds and drugs. Presented here are the results on the construction and characterization of three fusion proteins containing the N-terminally modified human cytochrome P450s CYP2C9, CY2C19 and CYP3A4 fused to the soluble NADPH-dependent oxidoreductase domain of CYP102A1 from Bacillus megaterium. The constructs, CYP2C9/BMR, CYP2C19/BMR and CYP3A4/BMR are well expressed in Escherichia coli as holo proteins. The chimeras can be purified in the absence of detergent and the purified enzymes are both active and correctly folded in the absence of detergent, as demonstrated by circular dichroism and functional studies. Additionally, in comparison with the parent P450 enzyme, these chimeras have greatly improved solubility properties. The chimeras are catalytically self-sufficient and present turnover rates similar to those reported for the native enzymes in reconstituted systems, unlike previously reported mammalian cytochrome P450 fusion proteins. Furthermore the specific activities of these chimeras are not dependent on the enzyme concentration present in the reaction buffer and they do not require the addition of accessory proteins, detergents or phospholipids to be fully active. The solubility, catalytic self-sufficiency and wild-type like activities of these chimeras would greatly simplify the studies of cytochrome P450 mediated drug metabolism in solution.
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Affiliation(s)
- Vikash Rajnikant Dodhia
- Division of Molecular Biosciences, Imperial College London, Biochemistry Building, South Kensington, London, SW7 2AY, UK
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11
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Yim SK, Ahn T, Jung HC, Pan JG, Yun CH. Temperature effect on the functional expression of human cytochromes P450 2A6 and 2E1 inEscherichia coli. Arch Pharm Res 2005; 28:433-7. [PMID: 15918516 DOI: 10.1007/bf02977672] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Human cytochromes P450 (CYP) 2A6 and 2E1 are of great interest because of their important roles in the oxidation of numerous drugs and carcinogens. Bacterial expression systems, especially Escherichia coli cells, have been widely used for the production of various CYP enzymes in order to obtain high yield of proteins. The expression methods usually employ longer culture time (30-72 h) at lower temperature (usually under 30 degrees C). Expression levels of CYPs 2A6 and 2E1 at 37 degrees C were compared to those at 280 degrees C, which is a usual temperature used in most bacterial expression systems for human CYP expression. Within 18 h the expression levels of CYPs 2A6 and 2E1 reached up to 360 and 560 nmol per liter culture at 37 degrees C, respectively, which are compatible with those of 36 h culture at 280 degrees C. The activities of CYPs expressed at 37 degrees C were also comparable to those expressed at 28 degrees C. The present over-expression system can be useful for rapid production of large amounts of active human CYPs 2A6 and 2E1 in E. coli.
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Affiliation(s)
- Sung-Kun Yim
- School of Biological Sciences and Technology, Chonnam National University, Gwangju 500-757, Korea
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12
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Boye SL, Kerdpin O, Elliot DJ, Miners JO, Kelly L, McKinnon RA, Bhasker CR, Yoovathaworn K, Birkett DJ. Optimizing bacterial expression of catalytically active human cytochromes P450: comparison of CYP2C8 and CYP2C9. Xenobiotica 2005; 34:49-60. [PMID: 14742136 DOI: 10.1080/00498250310001636868] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
1. Methods for the co-expression in Escherichia coli of human cytochrome P450 (CYP) 2C8 and CYP2C9 with NADPH-cytochrome P450 reductase (OxR) to produce a catalytically active system were compared. 2. Approaches assessed were expression of a CYP:OxR fusion construct, bicistronic plasmids, simultaneous transformation with CYP and OxR plasmids, and separate expression of CYP and OxR with reconstitution of activity by mixing the bacterial membranes. Two N-terminal modifications (Delta3-20 and 17alpha-leader) of the individual P450s were additionally investigated. 3. Each approach gave efficient expression of CYP2C8 and CYP2C9, but the bicistronic constructs under the expression conditions used gave low OxR expression and low catalytic activity. CYP expression was higher with the Delta3-20 construct for CYP2C9 and with the 17alpha-presequence construct for CYP2C8. 4. Using torsemide as substrate, all methods gave catalytically active systems with K(m) values similar to human liver microsomes. Mixing bacterial membranes containing separately expressed CYP and OxR reconstituted a catalytically active system with the Delta3-20 construct for CYP2C9 but not for CYP2C8, and with neither of the 17alpha- presequence constructs. OxR co-expressed with CYP in the same membrane interacted with CYP to reconstitute activity more effectively than addition of exogenous OxR membranes. 5. Expression construct and OxR co-expression strategy should be individualized for CYP isoforms.
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Affiliation(s)
- S L Boye
- Department of Clinical Pharmacology, Flinders University School of Medicine, Flinders Medical Centre, SA, Australia
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13
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Ahn T, Yang S, Yun CH. Enhanced expression of human cytochrome P450 1A2 by co-expression with human molecular chaperone Hsp70. Toxicol Lett 2004; 153:267-72. [PMID: 15451558 DOI: 10.1016/j.toxlet.2004.05.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2004] [Revised: 05/03/2004] [Accepted: 05/03/2004] [Indexed: 11/19/2022]
Abstract
Cytochrome P450 (CYP) 1A2 is of great interest because of its important roles in the oxidation of numerous drugs and carcinogens. Hsp70, a molecular chaperone in human, is known to assist the correct folding of unfolded proteins. To achieve high yield of recombinant human CYP1A2 in Escherichia coli, the CYP1A2 encoding gene was co-expressed with the chaperone Hsp70 under the control of an inducible tac promoter in bicistronic format. Expression level of CYP1A2 in the bicistronic construct reached up to 410 nmol (lculture)(-1) within 16 h at 37 degrees C, which is approximately 2.7-fold increase compared to the expression yield of CYP1A2 alone without Hsp70. The present over-expression system may be useful for rapid production of large amounts of active CYP1A2 in E. coli.
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Affiliation(s)
- Taeho Ahn
- Department of Biochemistry, College of Veterinary Medicine, Chonnam National University, Gwangju 500-757, Republic of Korea.
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14
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Ahn T, Yang S, Yun CH. High-level expression of human cytochrome P450 1A2 by co-expression with human molecular chaperone HDJ-1(Hsp40). Protein Expr Purif 2004; 36:48-52. [PMID: 15177283 DOI: 10.1016/j.pep.2004.03.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2003] [Revised: 03/09/2004] [Indexed: 11/30/2022]
Abstract
Human cytochrome P450 (CYP) 1A2 is of great interest because of its important roles in the oxidation of numerous drugs and carcinogens. HDJ-1, a molecular chaperone in human, is known to assist the correct folding of unfolded proteins. To achieve high yield of recombinant human CYP1A2 in Escherichia coli, the CYP1A2 encoding gene was co-expressed with the chaperone HDJ-1 under the control of an inducible tac promoter in bicistronic format. Expression level of CYP1A2 in the bicistronic construct reached up to 520 nmol/liter culture within 16 h at 37 degrees C, which is 3.4-fold increase compared to the expression yield of CYP1A2 alone without HDJ-1. By co-expression with HDJ-1, the catalytic activity of CYP1A2 was also increased 5.5-fold. The activity increase seems to be associated with the increase of CYP production at whole cell level. The present over-expression system may be useful for rapid production of large amounts of active human CYP1A2 in E. coli.
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Affiliation(s)
- Taeho Ahn
- Department of Biochemistry, College of Veterinary Medicine, Chonnam National University, Gwangju 500-757, Republic of Korea.
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15
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Ahn T, Yun CH. High-level expression of human cytochrome P450 3A4 by co-expression with Human molecular chaperone HDJ-1 (Hsp40). Arch Pharm Res 2004; 27:319-23. [PMID: 15089038 DOI: 10.1007/bf02980067] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Cytochrome P450 (CYP) 3A4 is of great interest because of its important roles in the oxidation of numerous drugs and xenobiotics. HDJ-1, a molecular chaperone in human, is known to assist the correct folding of unfolded proteins. To achieve a high yield of recombinant human CYP3A4 in Escherichia coli, the CYP3A4 encoding gene was co-expressed with the chaperone HDJ-1, under the control of an inducible tac promoter in a bicistronic format. The levels of expression of the CYP3A4 in the bicistronic construct reached up to 715 nmol (liter culture)(-1) within 16 h at 37 degrees C, which was about a 3.3-fold increase compared to that of the CYP3A4 alone without the HDJ-1. By co-expression with HDJ-1, the catalytic activity of CYP3A4 was also increased by approximately 15-fold. The amount of activity increase was similar to that of the CYP production at the whole cell level. The present over-expression system may be useful for the rapid production of large amounts of active CYP3A4 in E. coli.
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Affiliation(s)
- Taeho Ahn
- Department of Biochemistry, College of Veterinary Medicine, Chonnam National University, Gwangju 500-757, Korea.
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16
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Zhou H, Josephy PD, Kim D, Guengerich FP. Functional characterization of four allelic variants of human cytochrome P450 1A2. Arch Biochem Biophys 2004; 422:23-30. [PMID: 14725854 DOI: 10.1016/j.abb.2003.11.019] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Human cytochrome P450 1A2 catalyzes important reactions in xenobiotic metabolism, including the N-hydroxylation of carcinogenic aromatic amines. In 2001, Chevalier et al. reported four new P450 1A2 sequence variants in the human population. We have now expressed these variants in Escherichia coli and measured protein expression (optical spectroscopy of holoenzyme and immunoblotting) and bioactivation of IQ (2-amino-3-methylimidazo[4,5-f]quinoline) and MeIQ (2-amino-2,4-dimethylimidazo[4,5-f]quinoline) in the lacZ reversion mutagenicity test. Enzyme kinetic analyses were performed for N-hydroxylation of five heterocyclic amine substrates and for O-deethylation of phenacetin. The most drastic effect was that of the R431W substitution: no holoenzyme was detectable. This residue is located in the "meander" peptide region and earlier site-directed mutagenesis studies demonstrated that it is critical for maintenance of protein tertiary structure. The other three variants had subtly different catalytic activities compared to the wild-type enzyme.
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Affiliation(s)
- Huijia Zhou
- Department of Chemistry and Biochemistry, Guelph-Waterloo Centre for Graduate Work in Chemistry and Biochemistry, University of Guelph, Ont. N1G 2W1, Guelph, Canada
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17
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Nazarov PA, Drutsa VL, Miller WL, Shkumatov VM, Luzikov VN, Novikova LA. Formation and functioning of fused cholesterol side-chain cleavage enzymes. DNA Cell Biol 2003; 22:243-52. [PMID: 12823901 DOI: 10.1089/104454903321908638] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
We studied the properties of various fused combinations of the components of the mitochondrial cholesterol side-chain cleavage system including cytochrome P450scc, adrenodoxin (Adx), and adrenodoxin reductase (AdR). When recombinant DNAs encoding these constructs were expressed in Escherichia coli, both cholesterol side-chain cleavage activity and sensitivity to intracellular proteolysis of the three-component fusions depended on the species of origin and the arrangement of the constituents. To understand the assembly of the catalytic domains in the fused molecules, we analyzed the catalytic properties of three two-component fusions: P450scc-Adx, Adx-P450scc, and AdR-Adx. We examined the ability of each fusion to carry out the side-chain cleavage reaction in the presence of the corresponding missing component of the whole system and examined the dependence of this reaction on the presence of exogenously added individual components of the double fusions. This analysis indicated that the active centers in the double fusions are either unable to interact or are misfolded; in some cases they were inaccessible to exogenous partners. Our data suggest that when fusion proteins containing P450scc, Adx, and AdR undergo protein folding, the corresponding catalytic domains are not formed independently of each other. Thus, the correct folding and catalytic activity of each domain is determined interactively and not independently.
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Affiliation(s)
- Pavel A Nazarov
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Russia
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18
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Bell-Parikh LC, Hosea NA, Martin MV, Guengerich FP. Purification of cytochrome P-450 enzymes. CURRENT PROTOCOLS IN TOXICOLOGY 2002; Chapter 4:Unit4.2. [PMID: 23045082 DOI: 10.1002/0471140856.tx0402s12] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Among the liver P-450 xenobiotic-metabolizing enzymes, P450-2E1 is of interest because of its activation of potent carcinogens, and P-450 1A2 is of interest because of its role in oxidation of drugs and carcinogens. This unit describes column chromatography protocols for purification of recombinant forms of these enzymes expressed in a bacterial expression system.
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Affiliation(s)
- L C Bell-Parikh
- Vanderbilt University School of Medicine, Nashville, TN, USA
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19
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Deeni YY, Paine MJ, Ayrton AD, Clarke SE, Chenery R, Wolf CR. Expression, purification, and biochemical characterization of a human cytochrome P450 CYP2D6-NADPH cytochrome P450 reductase fusion protein. Arch Biochem Biophys 2001; 396:16-24. [PMID: 11716457 DOI: 10.1006/abbi.2001.2585] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Cytochrome P450 CYP2D6 metabolizes a wide range of pharmaceutical compounds. A CYP2D6 fusion enzyme (CYP2D6F), containing an amino-terminal human CYP2D6 sequence and a carboxyterminal human NADPH-cytochrome P450 oxidoreductase (CPR) moiety, was constructed. High levels of expression were achieved in Escherichia coli (60-100 nmol/liter) and the enzyme was catalytically active with optimal activities achieved in the presence of the antioxidant, GSH. Turnover values for bufuralol 1'-hydroxylation, metoprolol alpha-hydroxylation, O-desmethylation, and dextromethorphan O-demethylation, using membranes expressing the fusion enzyme, were 5.6, 0.4, 0.72, and 6.19 min(-1), respectively. These values were similar to E. coli membranes which coexpressed human CYP2D6 and CPR (CYP2D6/R). The K(m) and k(cat) values for bufuralol metabolism were estimated to be 10.2 microM and 4.1 min(-1), respectively. The enzyme was purified using ion-exchange chromatography, affinity chromatography (2'-5' ADP-Sepharose), and gel filtration. Estimated turnover rates for bufuralol 1'-hydroxylation, metoprolol alpha-hydroxylation, O-desmethylation, and dextromethorphan O-demethylation were 1.2, 0.52, 0.79, and 0.76 min(-1), respectively. Bufuralol 1'-hydroxylase activity by purified CYP2D6F was enhanced by phospholipids and added CPR. The CYP2D6F enzyme was able to stimulate CYP3A4 testosterone 6beta-hydroxylase activity in a reconstitution system indicating that electron transfer may be largely intermolecular. The catalytically self-sufficient CYP2D6F enzyme will facilitate investigations of P450-CPR interactions and the development of new biocatalysts.
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Affiliation(s)
- Y Y Deeni
- Biomedical Research Centre, University of Dundee, Dundee, DD1 9SY, United Kingdom
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Bell SG, Harford-Cross CF, Wong LL. Engineering the CYP101 system for in vivo oxidation of unnatural substrates. PROTEIN ENGINEERING 2001; 14:797-802. [PMID: 11739899 DOI: 10.1093/protein/14.10.797] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The protein engineering of CYP enzymes for structure-activity studies and the oxidation of unnatural substrates for biotechnological applications will be greatly facilitated by the availability of functional, whole-cell systems for substrate oxidation. We report the construction of a tricistronic plasmid that expresses the CYP101 monooxygenase from Pseudomonas putida, and its physiological electron transfer co-factor proteins putidaredoxin reductase and putidaredoxin in Escherichia coli, giving a functional in vivo catalytic system. Wild-type CYP101 expressed in this system efficiently transforms camphor to 5-exo-hydroxycamphor without further oxidation to 5-oxo-camphor until >95% of camphor has been consumed. CYP101 mutants with increased activity for the oxidation of diphenylmethane (the Y96F-I395G mutant), styrene and ethylbenzene (the Y96F-V247L mutant) have been engineered. In particular, the Y96F-V247L mutant shows coupling efficiency of approximately 60% for styrene and ethylbenzene oxidation, with substrate oxidation rates of approximately 100/min. Escherichia coli cells transformed with tricistronic plasmids expressing these mutants readily gave 100-mg quantities of 4-hydroxydiphenylmethane and 1-phenylethanol in 24-72 h. This new in vivo system can be used for preparative scale reactions for product characterization, and will greatly facilitate directed evolution of the CYP101 enzyme for enhanced activity and selectivity of substrate oxidation.
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Affiliation(s)
- S G Bell
- Department of Chemistry, Inorganic Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QR, UK
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Sadeghi SJ, Tsotsou GE, Fairhead M, Meharenna YT, Gilardi G. Rational Design of P450 Enzymes for Biotechnology. PHYSICS AND CHEMISTRY BASIS OF BIOTECHNOLOGY 2001. [DOI: 10.1007/0-306-46891-3_3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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Shimada T, Tsumura F, Gillam EM, Guengerich FP, Inoue K. Roles of NADPH-P450 reductase in the O-deethylation of 7-ethoxycoumarin by recombinant human cytochrome P450 1B1 variants in Escherichia coli. Protein Expr Purif 2000; 20:73-80. [PMID: 11035953 DOI: 10.1006/prep.2000.1302] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Four human cytochrome P450 1B1 (CYP1B1) allelic variants were purified from membranes of Escherichia coli in which respective CYP1B1 cDNAs and human NADPH-P450 reductase cDNA have been introduced. Purified CYP1B1 variants were used to reconstitute 7-ethoxycoumarin O-deethylation activities with purified rabbit liver or recombinant (rat) NADPH-P450 reductase in the phospholipid vesicles and compared with those catalyzed by CYP1B1 enzymes in the membranes of E. coli in monocistronic (by adding the reductase) and bicistronic (without addition of extra reductase) systems. In the bicistronic system, the ratio of expression of NADPH-P450 reductase to CYP1B1 proteins was found to range from 0.2 to 0.5. Purified CYP1B1 enzymes (under optimal reconstitution conditions) catalyzed 7-ethoxycoumarin O-deethylation at rates one-third to one-fourth of those catalyzed by membranes of E. coli coexpressing CYP1B1 and the reductase proteins. Full catalytic activities in reconstituted systems were achieved with a twofold molar excess of NADPH-P450 reductase to CYP1B1; in membranes of E. coli with the monocistronic CYP1B1 construct, an eightfold molar excess of reductase to CYP1B1 was required. However, in membranes of bicistronic constructs, there was no additional stimulation of 7-ethoxycoumarin O-deethylation by extra NADPH-P450 reductase, despite the fact that the molar ratio of expression levels of reductase to CYP1B1 was <0.5. These results suggest that NADPH-P450 reductase produced in the bacterial membranes is more active in interacting with CYP1B1 proteins in the bicistronic system than the reductase added to artificial phospholipid vesicles or bacterial membranes.
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Affiliation(s)
- T Shimada
- Osaka Prefectural Institute of Public Health, 3-69 Nakamichi 1-chome, Higashinari-ku, Osaka, 537-0025, Japan.
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Guengerich FP, Parikh A, Yun CH, Kim D, Nakamura K, Notley LM, Gillam EM. What makes P450s work? Searches for answers with known and new P450s. Drug Metab Rev 2000; 32:267-81. [PMID: 11139129 DOI: 10.1081/dmr-100102334] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Random mutagenesis has been developed as an approach for the study of human cytochrome P450 (P450) enzymes and their structure and function. Sensitive screening methods are critical for the success of this approach. We have developed one system that takes advantage of the ability of human P450 1A2 to activate heterocyclic amines to mutagenic products [A. Parikh, P. D. Josephy, and F. P. Guengerich, Biochemistry, 38, 5283-5289 (1999)]. Mutants with both attenuated and enhanced activity have been recovered and subjected to further kinetic analysis. For phenacetin O-deethylation, the E225I mutant had kcat 6x > wild type; D320A had kcat 1/10x < wild type (and Km 15 x > wild type). With all three P450s, the rate of first electron reduction was similar, and all had similar binding constants for phenacetin (approximately 15 microM). All three forms yielded intermolecular, noncompetitive kinetic deuterium isotope effects of 1.5-2 [DV and D(V/K)] for O-deethylation of [OCD2CH3]-phenacetin. All three forms of P450 1A2 also formed a minor product, the acetol (C-hydroxylation of the acetyl group). This reaction had a deuterium isotope effect of approximately 14 with all three forms of the enzyme, and C-H bond breaking is the rate-determining step. Another approach to P450 2A6 involves the recent observation that this P450 can accumulate indigo [E. M. J. Gillam, A. M. A. Aguinaldo, L. M. Notley, D. Kim, R. G. Mundkowski, A. A. Volkov, F. H. Arnold, P. Soucek, J. T. DeVoss, and F. P. Guengerich, Biochem. Biophys. Res. Commun 265, 469-472 (1999)]. Current results indicate that this process involves the conversion of endogenous indole to indoxyl by the P450. The reaction may be used in assays of random mutants and has some potential applications in industry.
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Affiliation(s)
- F P Guengerich
- Department of Biochemistry and Center in Molecular Toxicology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146, USA.
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Gillam EM. Human cytochrome P450 enzymes expressed in bacteria: reagents to probe molecular interactions in toxicology. Clin Exp Pharmacol Physiol 1998; 25:877-86. [PMID: 9807658 DOI: 10.1111/j.1440-1681.1998.tb02338.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
1. Phase I metabolism of drugs is accomplished by the concerted actions of a limited number of cytochrome P450 enzymes with wide but often overlapping substrate specificites. Although metabolism generally accelerates the clearance of drugs, reactive products may also be generated that cause toxic effects. 2. Because individuals vary in the range and levels of different P450 forms, it is useful to be able to determine the specific isoforms involved in a particular metabolic reaction, in order to estimate the extent of variation within a population in the pharmacokinetics of specific drugs. Such studies may also allow predictions to be made regarding the relative susceptibility of different individuals to possible adverse effects associated with drug treatment. 3. Human cytochrome P450 enzymes are now routinely expressed as recombinant proteins in many different systems, including mammalian cell culture, yeast, baculovirus and Escherichia coli. The latter system is particularly useful when large amounts of protein are required for biophysical studies, but can also be adapted to routine examination of pathways of drug metabolism and toxicology. 4. The present review provides an analysis of strategies used for enhancing cytochrome P450 expression in bacteria and for examining the activity of the recombinant proteins. The potential applications of recombinant P450 are discussed, with particular emphasis on investigation of the roles of cytochrome P450 forms in the metabolism and the toxicity of drugs.
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Affiliation(s)
- E M Gillam
- Department of Physiology and Pharmacology, University of Queensland, St Lucia, Australia.
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Chun YJ. Expression of recombinant human cytochrome P450 1A2 in Escherichia coli bacterial mutagenicity tester strain. Arch Pharm Res 1998; 21:305-9. [PMID: 9875448 DOI: 10.1007/bf02975292] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Human cytochrome P450 1A2 is one of the major cytochrome P450s in human liver. It is known to be capable of activating a number of carcinogens such as arylamines and heterocyclic amines. In order to develop the new bacterial mutagenicity test system with human P450, a full length of human P450 1A2 cDNA inserted into pCW bacterial expression vector was introduced to Escherichia coli WP2 uvrA strain which is a well-known E. coli strain for bacterial reverse mutagenicity assay. Expressed human P450 1A2 showed typical P450 hemoprotein spectra. Maximum expression was achieved at 48 hrs after incubating at 30 degrees C in terrific broth containing ampicillin, IPTG and other supplements. High level expression of P 450 1A2 in E. coli WP2 uvrA membranes was determined in SDS-PAGE. The well-known mutagens 2-aminoanthracene and MelQ increased the revertant colonies of E. coli WP2 uvrA expressing human P450 1A2 without an exogenous rat hepatic post-mitochondrial supernatant (S9 fraction) in a dose-dependent manner. The results show that the functional expression of human P450 in bacterial mutagenicity tester strain will provide a useful tool for studying the mechanism of the mutagenesis and carcinogenesis of new drugs and environmental chemicals.
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Affiliation(s)
- Y J Chun
- College of Pharmacy, Chung Ang University, Seoul, Korea
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Abstract
A principal advance in the production of drug-metabolizing enzymes has been the development of catalytically self-sufficient cytochrome P450 systems, including additional P450-reductase fusion proteins and Escherichia coli and baculovirus coexpression constructs. Continuing work with glutathione transferases has resulted in the identification of important residues by random mutagenesis screening techniques, as well as in the engineering of model Salmonella typhimurium strains for genotoxicity analysis.
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Affiliation(s)
- F P Guengerich
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
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Parikh A, Gillam EM, Guengerich FP. Drug metabolism by Escherichia coli expressing human cytochromes P450. Nat Biotechnol 1997; 15:784-8. [PMID: 9255795 DOI: 10.1038/nbt0897-784] [Citation(s) in RCA: 230] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The broad substrate specificity of the cytochrome P450 (P450) enzyme superfamily of heme-thiolate proteins lends itself to diverse environmental and pharmaceutical applications. Until recently, the primary drawback in using living bacteria to catalyze mammalian P450-mediated reactions has been the paucity of electron transport from NADPH to P450 via endogenous flavoproteins. We report the functional expression in Escherichia coli of bicistronic constructs consisting of a human microsomal P450 enzyme encoded by the first cistron and the auxiliary protein NADPH-P450 reductase by the second. Expression levels of P450s ranged from 35 nmol per liter culture to 350 nmol per liter culture, with expression of NADPH-P450 reductase typically ranging from 50% to 100% of that of P450. Transformed bacteria metabolized a number of typical P450 substrates at levels comparable to isolated bacterial membranes fortified with an NADPH-generating system. These rates compare favorably with those obtained using human liver microsomes as well as those of reconstituted in vitro systems composed of purified proteins, lipids, and cofactors.
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Affiliation(s)
- A Parikh
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
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