1
|
Ye G, Li J, Yu W, Xie Z, Zheng G, Liu W, Wang S, Cao Q, Lin J, Su Z, Li D, Che Y, Fan S, Wang P, Wu Y, Shen H. ALKBH5 facilitates CYP1B1 mRNA degradation via m6A demethylation to alleviate MSC senescence and osteoarthritis progression. Exp Mol Med 2023; 55:1743-1756. [PMID: 37524872 PMCID: PMC10474288 DOI: 10.1038/s12276-023-01059-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2022] [Revised: 04/01/2023] [Accepted: 05/24/2023] [Indexed: 08/02/2023] Open
Abstract
Improving health and delaying aging is the focus of medical research. Previous studies have shown that mesenchymal stem cell (MSC) senescence is closely related to organic aging and the development of aging-related diseases such as osteoarthritis (OA). m6A is a common RNA modification that plays an important role in regulating cell biological functions, and ALKBH5 is one of the key m6A demethylases. However, the role of m6A and ALKBH5 in MSC senescence is still unclear. Here, we found that the m6A level was enhanced and ALKBH5 expression was decreased in aging MSCs induced by multiple replications, H2O2 stimulation or UV irradiation. Downregulation of ALKBH5 expression facilitated MSC senescence by enhancing the stability of CYP1B1 mRNA and inducing mitochondrial dysfunction. In addition, IGF2BP1 was identified as the m6A reader restraining the degradation of m6A-modified CYP1B1 mRNA. Furthermore, Alkbh5 knockout in MSCs aggravated spontaneous OA in mice, and overexpression of Alkbh5 improved the efficacy of MSCs in OA. Overall, this study revealed a novel mechanism of m6A in MSC senescence and identified promising targets to protect against aging and OA.
Collapse
Affiliation(s)
- Guiwen Ye
- Department of Orthopedics, The Eighth Affiliated Hospital, Sun Yat-sen University, Shenzhen, 518033, PR China
| | - Jinteng Li
- Department of Orthopedics, The Eighth Affiliated Hospital, Sun Yat-sen University, Shenzhen, 518033, PR China
| | - Wenhui Yu
- Department of Orthopedics, The Eighth Affiliated Hospital, Sun Yat-sen University, Shenzhen, 518033, PR China
| | - Zhongyu Xie
- Department of Orthopedics, The Eighth Affiliated Hospital, Sun Yat-sen University, Shenzhen, 518033, PR China
| | - Guan Zheng
- Department of Orthopedics, The Eighth Affiliated Hospital, Sun Yat-sen University, Shenzhen, 518033, PR China
| | - Wenjie Liu
- Department of Orthopedics, The Eighth Affiliated Hospital, Sun Yat-sen University, Shenzhen, 518033, PR China
| | - Shan Wang
- Center for Biotherapy, The Eighth Affiliated Hospital, Sun Yat-sen University, Shenzhen, 518033, PR China
| | - Qian Cao
- Center for Biotherapy, The Eighth Affiliated Hospital, Sun Yat-sen University, Shenzhen, 518033, PR China
| | - Jiajie Lin
- Department of Orthopedics, The Eighth Affiliated Hospital, Sun Yat-sen University, Shenzhen, 518033, PR China
| | - Zepeng Su
- Department of Orthopedics, The Eighth Affiliated Hospital, Sun Yat-sen University, Shenzhen, 518033, PR China
| | - Dateng Li
- Department of Statistical Science, Southern Methodist University, Dallas, TX, USA
| | - Yunshu Che
- Department of Orthopedics, The Eighth Affiliated Hospital, Sun Yat-sen University, Shenzhen, 518033, PR China
| | - Shuai Fan
- Department of Orthopedics, The Eighth Affiliated Hospital, Sun Yat-sen University, Shenzhen, 518033, PR China
| | - Peng Wang
- Department of Orthopedics, The Eighth Affiliated Hospital, Sun Yat-sen University, Shenzhen, 518033, PR China.
| | - Yanfeng Wu
- Center for Biotherapy, The Eighth Affiliated Hospital, Sun Yat-sen University, Shenzhen, 518033, PR China.
| | - Huiyong Shen
- Department of Orthopedics, The Eighth Affiliated Hospital, Sun Yat-sen University, Shenzhen, 518033, PR China.
| |
Collapse
|
2
|
Mokkawes T, de Visser SP. Melatonin Activation by Cytochrome P450 Isozymes: How Does CYP1A2 Compare to CYP1A1? Int J Mol Sci 2023; 24:ijms24043651. [PMID: 36835057 PMCID: PMC9959256 DOI: 10.3390/ijms24043651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Revised: 02/09/2023] [Accepted: 02/09/2023] [Indexed: 02/16/2023] Open
Abstract
Cytochrome P450 enzymes are versatile enzymes found in most biosystems that catalyze mono-oxygenation reactions as a means of biosynthesis and biodegradation steps. In the liver, they metabolize xenobiotics, but there are a range of isozymes with differences in three-dimensional structure and protein chain. Consequently, the various P450 isozymes react with substrates differently and give varying product distributions. To understand how melatonin is activated by the P450s in the liver, we did a thorough molecular dynamics and quantum mechanics study on cytochrome P450 1A2 activation of melatonin forming 6-hydroxymelatonin and N-acetylserotonin products through aromatic hydroxylation and O-demethylation pathways, respectively. We started from crystal structure coordinates and docked substrate into the model, and obtained ten strong binding conformations with the substrate in the active site. Subsequently, for each of the ten substrate orientations, long (up to 1 μs) molecular dynamics simulations were run. We then analyzed the orientations of the substrate with respect to the heme for all snapshots. Interestingly, the shortest distance does not correspond to the group that is expected to be activated. However, the substrate positioning gives insight into the protein residues it interacts with. Thereafter, quantum chemical cluster models were created and the substrate hydroxylation pathways calculated with density functional theory. These relative barrier heights confirm the experimental product distributions and highlight why certain products are obtained. We make a detailed comparison with previous results on CYP1A1 and identify their reactivity differences with melatonin.
Collapse
Affiliation(s)
- Thirakorn Mokkawes
- Manchester Institute of Biotechnology, The University of Manchester, 131 Princess Street, Manchester M1 7DN, UK
- Department of Chemical Engineering, The University of Manchester, Oxford Road, Manchester M13 9PL, UK
| | - Sam P. de Visser
- Manchester Institute of Biotechnology, The University of Manchester, 131 Princess Street, Manchester M1 7DN, UK
- Department of Chemical Engineering, The University of Manchester, Oxford Road, Manchester M13 9PL, UK
- Correspondence:
| |
Collapse
|
3
|
Le TK, Kim J, Anh Nguyen N, Huong Ha Nguyen T, Sun EG, Yee SM, Kang HS, Yeom SJ, Beum Park C, Yun CH. Solar-Powered Whole-Cell P450 Catalytic Platform for C-Hydroxylation Reactions. CHEMSUSCHEM 2021; 14:3054-3058. [PMID: 34085413 DOI: 10.1002/cssc.202100944] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 06/02/2021] [Indexed: 06/12/2023]
Abstract
Photobiocatalysis is a green platform for driving redox enzymatic reactions using solar energy, not needing high-cost cofactors and redox partners. Here, a visible light-driven whole-cell platform for human cytochrome P450 (CYP) photobiocatalysis was developed using natural flavins as a photosensitizer. Photoexcited flavins mediate NADPH/reductase-free, light-driven biocatalysis by human CYP2E1 both in vitro and in the whole-cell systems. In vitro tests demonstrated that the photobiocatalytic activity of CYP2E1 is dependent on the substrate type, the presence of catalase, and the acid type used as a sacificial electron donor. A protective effect of catalase was found against the inactivation of CYP2E1 heme by H2 O2 and the direct transfer of photo-induced electrons to the heme iron not by peroxide shunt. Furthermore, the P450 photobiocatalysis in whole cells containing human CYPs 1A1, 1A2, 1B1, and 3A4 demonstrated the general applicability of the solar-powered, flavin-mediated P450 photobiocatalytic system.
Collapse
Affiliation(s)
- Thien-Kim Le
- School of Biological Sciences and Technology, Chonnam National University, Gwangju, 61186, Republic of Korea
| | - Jinhyun Kim
- Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), 335 Science Road, Daejeon, 34141, Republic of Korea
| | - Ngoc Anh Nguyen
- School of Biological Sciences and Technology, Chonnam National University, Gwangju, 61186, Republic of Korea
| | - Thi Huong Ha Nguyen
- School of Biological Sciences and Technology, Chonnam National University, Gwangju, 61186, Republic of Korea
| | - Eun-Gene Sun
- School of Biological Sciences and Technology, Chonnam National University, Gwangju, 61186, Republic of Korea
| | - Su-Min Yee
- School of Biological Sciences and Technology, Chonnam National University, Gwangju, 61186, Republic of Korea
| | - Hyung-Sik Kang
- School of Biological Sciences and Technology, Chonnam National University, Gwangju, 61186, Republic of Korea
| | - Soo-Jin Yeom
- School of Biological Sciences and Technology, Chonnam National University, Gwangju, 61186, Republic of Korea
| | - Chan Beum Park
- Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), 335 Science Road, Daejeon, 34141, Republic of Korea
| | - Chul-Ho Yun
- School of Biological Sciences and Technology, Chonnam National University, Gwangju, 61186, Republic of Korea
| |
Collapse
|
4
|
Estrada DF, Kumar A, Campomizzi CS, Jay N. Crystal Structures of Drug-Metabolizing CYPs. Methods Mol Biol 2021; 2342:171-192. [PMID: 34272695 PMCID: PMC10813703 DOI: 10.1007/978-1-0716-1554-6_7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The complex enzyme kinetics displayed by drug-metabolizing cytochrome P450 enzymes (CYPs) (see Chapter 9 ) can, in part, be explained by an examination of their crystallographic protein structures. Fortunately, despite low sequence similarity between different families of drug-metabolizing CYPs, there exists a high degree of structural homology within the superfamily. This similarity in the protein fold allows for a direct comparison of the structural features of CYPs that contribute toward differences in substrate binding, heterotropic and homotropic cooperativity, and genetic variability in drug metabolism. In this chapter, we first provide an overview of the nomenclature and the role of structural features that are common in all CYPs. We then apply these definitions to understand the different substrate specificities and functions in the CYP3A, CYP2C, and CYP2D families of enzymes.
Collapse
Affiliation(s)
| | - Amit Kumar
- Department of Biochemistry, University at Buffalo, Buffalo, NY, USA
| | | | - Natalie Jay
- Department of Biochemistry, University at Buffalo, Buffalo, NY, USA
| |
Collapse
|
5
|
Liu Q, Beyraghdar Kashkooli A, Manzano D, Pateraki I, Richard L, Kolkman P, Lucas MF, Guallar V, de Vos RCH, Franssen MCR, van der Krol A, Bouwmeester H. Kauniolide synthase is a P450 with unusual hydroxylation and cyclization-elimination activity. Nat Commun 2018; 9:4657. [PMID: 30405138 PMCID: PMC6220293 DOI: 10.1038/s41467-018-06565-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2017] [Accepted: 07/31/2018] [Indexed: 01/06/2023] Open
Abstract
Guaianolides are an important class of sesquiterpene lactones with unique biological and pharmaceutical properties. They have been postulated to be derived from germacranolides, but for years no progress has been made in the elucidation of their biosynthesis that requires an unknown cyclization mechanism. Here we demonstrate the isolation and characterization of a cytochrome P450 from feverfew (Tanacetum parthenium), kauniolide synthase. Kauniolide synthase catalyses the formation of the guaianolide kauniolide from the germacranolide substrate costunolide. Unlike most cytochrome P450s, kauniolide synthase combines stereoselective hydroxylation of costunolide at the C3 position, with water elimination, cyclization and regioselective deprotonation. This unique mechanism of action is supported by in silico modelling and docking experiments. The full kauniolide biosynthesis pathway is reconstructed in the heterologous hosts Nicotiana benthamiana and yeast, paving the way for biotechnological production of guaianolide-type sesquiterpene lactones.
Collapse
Affiliation(s)
- Qing Liu
- Laboratory of Plant Physiology, Wageningen University and Research, Droevendaalsesteeg 1, 6708 PB, Wageningen, The Netherlands
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, Frederiksberg, 1871, Denmark
| | - Arman Beyraghdar Kashkooli
- Laboratory of Plant Physiology, Wageningen University and Research, Droevendaalsesteeg 1, 6708 PB, Wageningen, The Netherlands.
| | - David Manzano
- Plant Metabolism and Metabolic Engineering Program, Centre for Research in Agricultural Genomics (CRAG) (CSIC-IRTA-UAB-UB), 08193, Barcelona, Spain
- Department of Biochemistry and Physiology, Faculty of Pharmacy and Food Sciences, University of Barcelona, Campus Diagonal, Av. de Joan XXIII, 27-31, 08028, Barcelona, Spain
| | - Irini Pateraki
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, Frederiksberg, 1871, Denmark
| | - Lea Richard
- Laboratory of Plant Physiology, Wageningen University and Research, Droevendaalsesteeg 1, 6708 PB, Wageningen, The Netherlands
| | - Pim Kolkman
- Laboratory of Plant Physiology, Wageningen University and Research, Droevendaalsesteeg 1, 6708 PB, Wageningen, The Netherlands
| | - Maria Fátima Lucas
- Barcelona Supercomputing Center (BSC), C/ Jordi Girona 29, 08034, Barcelona, Spain
| | - Victor Guallar
- Barcelona Supercomputing Center (BSC), C/ Jordi Girona 29, 08034, Barcelona, Spain
- ICREA, Pg Lluís Companys 23, 08010, Barcelona, Spain
| | - Ric C H de Vos
- Wageningen Plant Research, Wageningen University and Research, Droevendaalsesteeg 1, 6708 PB, Wageningen, The Netherlands
| | - Maurice C R Franssen
- Laboratory of Organic Chemistry, Wageningen University, Stippeneng 4, 6708 WE, Wageningen, The Netherlands
| | - Alexander van der Krol
- Laboratory of Plant Physiology, Wageningen University and Research, Droevendaalsesteeg 1, 6708 PB, Wageningen, The Netherlands
| | - Harro Bouwmeester
- Laboratory of Plant Physiology, Wageningen University and Research, Droevendaalsesteeg 1, 6708 PB, Wageningen, The Netherlands.
- Plant Hormone Biology group, Swammerdam Institute for Life Sciences, University of Amsterdam, Science Park 904, 1098 XH, Amsterdam, The Netherlands.
| |
Collapse
|
6
|
Rudolf JD, Chang CY, Ma M, Shen B. Cytochromes P450 for natural product biosynthesis in Streptomyces: sequence, structure, and function. Nat Prod Rep 2017; 34:1141-1172. [PMID: 28758170 PMCID: PMC5585785 DOI: 10.1039/c7np00034k] [Citation(s) in RCA: 133] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Covering: up to January 2017Cytochrome P450 enzymes (P450s) are some of the most exquisite and versatile biocatalysts found in nature. In addition to their well-known roles in steroid biosynthesis and drug metabolism in humans, P450s are key players in natural product biosynthetic pathways. Natural products, the most chemically and structurally diverse small molecules known, require an extensive collection of P450s to accept and functionalize their unique scaffolds. In this review, we survey the current catalytic landscape of P450s within the Streptomyces genus, one of the most prolific producers of natural products, and comprehensively summarize the functionally characterized P450s from Streptomyces. A sequence similarity network of >8500 P450s revealed insights into the sequence-function relationships of these oxygen-dependent metalloenzymes. Although only ∼2.4% and <0.4% of streptomycete P450s have been functionally and structurally characterized, respectively, the study of streptomycete P450s involved in the biosynthesis of natural products has revealed their diverse roles in nature, expanded their catalytic repertoire, created structural and mechanistic paradigms, and exposed their potential for biomedical and biotechnological applications. Continued study of these remarkable enzymes will undoubtedly expose their true complement of chemical and biological capabilities.
Collapse
Affiliation(s)
- Jeffrey D Rudolf
- Department of Chemistry, The Scripps Research Institute, Jupiter, FL 33458, USA
| | | | | | | |
Collapse
|
7
|
Harris KL, Thomson RES, Strohmaier SJ, Gumulya Y, Gillam EMJ. Determinants of thermostability in the cytochrome P450 fold. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2017; 1866:97-115. [PMID: 28822812 DOI: 10.1016/j.bbapap.2017.08.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Revised: 07/19/2017] [Accepted: 08/07/2017] [Indexed: 10/19/2022]
Abstract
Cytochromes P450 are found throughout the biosphere in a wide range of environments, serving a multitude of physiological functions. The ubiquity of the P450 fold suggests that it has been co-opted by evolution many times, and likely presents a useful compromise between structural stability and conformational flexibility. The diversity of substrates metabolized and reactions catalyzed by P450s makes them attractive starting materials for use as biocatalysts of commercially useful reactions. However, process conditions impose different requirements on enzymes to those in which they have evolved naturally. Most natural environments are relatively mild, and therefore most P450s have not been selected in Nature for the ability to withstand temperatures above ~40°C, yet industrial processes frequently require extended incubations at much higher temperatures. Thus, there has been considerable interest and effort invested in finding or engineering thermostable P450 systems. Numerous P450s have now been identified in thermophilic organisms and analysis of their structures provides information as to mechanisms by which the P450 fold can be stabilized. In addition, protein engineering, particularly by directed or artificial evolution, has revealed mutations that serve to stabilize particular mesophilic enzymes of interest. Here we review the current understanding of thermostability as it applies to the P450 fold, gleaned from the analysis of P450s characterized from thermophilic organisms and the parallel engineering of mesophilic forms for greater thermostability. We then present a perspective on how this information might be used to design stable P450 enzymes for industrial application. 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.
Collapse
Affiliation(s)
- Kurt L Harris
- School of Chemistry and Molecular Biosciences, The University of Queensland, St. Lucia 4072, Australia
| | - Raine E S Thomson
- School of Chemistry and Molecular Biosciences, The University of Queensland, St. Lucia 4072, Australia
| | - Silja J Strohmaier
- School of Chemistry and Molecular Biosciences, The University of Queensland, St. Lucia 4072, Australia
| | - Yosephine Gumulya
- School of Chemistry and Molecular Biosciences, The University of Queensland, St. Lucia 4072, Australia
| | - Elizabeth M J Gillam
- School of Chemistry and Molecular Biosciences, The University of Queensland, St. Lucia 4072, Australia.
| |
Collapse
|
8
|
Daduang R, Kitani S, Sudoh Y, Grace Umadhay Pait I, Thamchaipenet A, Ikeda H, Igarashi Y, Nihira T. 29-Deoxymaklamicin, a new maklamicin analogue produced by a genetically engineered strain of Micromonospora sp. NBRC 110955. J Biosci Bioeng 2015; 120:608-13. [PMID: 25939549 DOI: 10.1016/j.jbiosc.2015.04.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2015] [Revised: 03/18/2015] [Accepted: 04/06/2015] [Indexed: 01/24/2023]
Abstract
Maklamicin is a spirotetronate-class antibiotic produced by Micromonospora sp. NBRC 110955, and a polyketide assembly line and a glycerate utilization system are involved in its biosynthesis. One tailoring step in the biosynthesis is predicted to be post-polyketide synthase (PKS) modification, which seems to be catalysed by putative cytochrome P450 monooxygenases, MakC2 and/or MakC3. In this study, we characterized makC2 and makC3 in the biosynthesis of maklamicin and identified a new maklamicin analogue from a makC2 disruptant. Gene deletion of makC2 resulted in the complete loss of maklamicin production with concomitant accumulation of a new compound (29-deoxymaklamicin), while gene deletion of makC3 did not affect the maklamicin production, indicating that 29-deoxymaklamicin is an intermediate in the biosynthetic pathway of maklamicin and should serve as the substrate of MakC2. 29-Deoxymaklamicin showed strong-to-modest anti-microbial activity against gram-positive bacteria. The fact that Streptomyces avermitilis heterologously expressing makC2 successfully converted 29-deoxymaklamicin into maklamicin confirmed that MakC2 is the final-step hydroxylase in the formation of mature maklamicin.
Collapse
Affiliation(s)
- Ratama Daduang
- International Center for Biotechnology, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Shigeru Kitani
- International Center for Biotechnology, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Yuri Sudoh
- Hyphagenesis Inc., 6-2-37 Tamagawa Gakuen, Machida, Tokyo 194-0041, Japan
| | - Ivy Grace Umadhay Pait
- International Center for Biotechnology, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Arinthip Thamchaipenet
- Department of Genetics, Faculty of Science, Kasetsart University, Chatuchak, Bangkok 10900, Thailand
| | - Haruo Ikeda
- Kitasato Institute for Life Sciences, Kitasato University, 1-15-1 Kitasato, Sagamihara, Kanagawa 252-0373, Japan
| | - Yasuhiro Igarashi
- Biotechnology Research Center, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama 939-0398, Japan
| | - Takuya Nihira
- International Center for Biotechnology, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan; MU-OU Collaborative Research Center for Bioscience and Biotechnology, Faculty of Science, Mahidol University, Rama VI Rd., Bangkok 10400, Thailand.
| |
Collapse
|
9
|
Hlavica P. Mechanistic basis of electron transfer to cytochromes p450 by natural redox partners and artificial donor constructs. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2015; 851:247-97. [PMID: 26002739 DOI: 10.1007/978-3-319-16009-2_10] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Cytochromes P450 (P450s) are hemoproteins catalyzing oxidative biotransformation of a vast array of natural and xenobiotic compounds. Reducing equivalents required for dioxygen cleavage and substrate hydroxylation originate from different redox partners including diflavin reductases, flavodoxins, ferredoxins and phthalate dioxygenase reductase (PDR)-type proteins. Accordingly, circumstantial analysis of structural and physicochemical features governing donor-acceptor recognition and electron transfer poses an intriguing challenge. Thus, conformational flexibility reflected by togging between closed and open states of solvent exposed patches on the redox components was shown to be instrumental to steered electron transmission. Here, the membrane-interactive tails of the P450 enzymes and donor proteins were recognized to be crucial to proper orientation toward each other of surface sites on the redox modules steering functional coupling. Also, mobile electron shuttling may come into play. While charge-pairing mechanisms are of primary importance in attraction and complexation of the redox partners, hydrophobic and van der Waals cohesion forces play a minor role in docking events. Due to catalytic plasticity of P450 enzymes, there is considerable promise in biotechnological applications. Here, deeper insight into the mechanistic basis of the redox machinery will permit optimization of redox processes via directed evolution and DNA shuffling. Thus, creation of hybrid systems by fusion of the modified heme domain of P450s with proteinaceous electron carriers helps obviate the tedious reconstitution procedure and induces novel activities. Also, P450-based amperometric biosensors may open new vistas in pharmaceutical and clinical implementation and environmental monitoring.
Collapse
Affiliation(s)
- Peter Hlavica
- Walther-Straub-Institut für Pharmakologie und Toxikologie der LMU, Goethestrasse 33, 80336, München, Germany,
| |
Collapse
|