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Chen W, Lynch JNC, Bustamante C, Zhang Y, Wong LL. Selective Oxidation of Vitamin D 3 Enhanced by Long-Range Effects of a Substrate Channel Mutation in Cytochrome P450 BM3 (CYP102A1). Chemistry 2024:e202401487. [PMID: 38963680 DOI: 10.1002/chem.202401487] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2024] [Revised: 07/02/2024] [Accepted: 07/03/2024] [Indexed: 07/05/2024]
Abstract
Vitamin D deficiency affects nearly half the population, with many requiring or opting for supplements with vitamin D3 (VD3), the precursor of vitamin D (1α,25-dihydroxyVD3). 25-HydroxyVD3, the circulating form of vitamin D, is a more effective supplement than VD3 but its synthesis is complex. We report here the engineering of cytochrome P450BM3 (CYP102A1) for the selective oxidation of VD3 to 25-hydroxyVD3. Long-range effects of the substrate-channel mutation Glu435Ile promoted binding of the VD3 side chain close to the heme, enhancing VD3 oxidation activity that reached 6.62 g of 25-hydroxyVD3 isolated from a 1-litre scale reaction (69.1 % yield; space-time-yield 331 mg/L/h).
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Affiliation(s)
- Wenyu Chen
- Department of Chemistry, University of Oxford Inorganic Chemistry Laboratory, South Parks Road, Oxford, OX1 3QR, UK
- Oxford Suzhou Centre for Advanced Research, Ruo Shui Road, Suzhou Industrial Park, Jiangsu, 215123, P.R. China
| | - Jamie N C Lynch
- Department of Chemistry, University of Oxford Inorganic Chemistry Laboratory, South Parks Road, Oxford, OX1 3QR, UK
| | - Claudia Bustamante
- Department of Chemistry, University of Oxford Inorganic Chemistry Laboratory, South Parks Road, Oxford, OX1 3QR, UK
| | - Yuan Zhang
- Department of Chemistry, University of Oxford Inorganic Chemistry Laboratory, South Parks Road, Oxford, OX1 3QR, UK
- Oxford Suzhou Centre for Advanced Research, Ruo Shui Road, Suzhou Industrial Park, Jiangsu, 215123, P.R. China
| | - Luet L Wong
- Department of Chemistry, University of Oxford Inorganic Chemistry Laboratory, South Parks Road, Oxford, OX1 3QR, UK
- Oxford Suzhou Centre for Advanced Research, Ruo Shui Road, Suzhou Industrial Park, Jiangsu, 215123, P.R. China
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2
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Zhan T, Jacoby C, Jede M, Knapp B, Ferlaino S, Günter A, Drepper F, Müller M, Weber S, Boll M. Bacterial stigmasterol degradation involving radical flavin delta-24 desaturase and molybdenum-dependent C26 hydroxylase. J Biol Chem 2024; 300:107243. [PMID: 38556086 PMCID: PMC11061730 DOI: 10.1016/j.jbc.2024.107243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2024] [Revised: 03/20/2024] [Accepted: 03/24/2024] [Indexed: 04/02/2024] Open
Abstract
Sterols are ubiquitous membrane constituents that persist to a large extent in the environment due to their water insolubility and chemical inertness. Recently, an oxygenase-independent sterol degradation pathway was discovered in a cholesterol-grown denitrifying bacterium Sterolibacterium (S.) denitrificans. It achieves hydroxylation of the unactivated primary C26 of the isoprenoid side chain to an allylic alcohol via a phosphorylated intermediate in a four-step ATP-dependent enzyme cascade. However, this pathway is incompatible with the degradation of widely distributed steroids containing a double bond at C22 in the isoprenoid side chain such as the plant sterol stigmasterol. Here, we have enriched a prototypical delta-24 desaturase from S. denitrificans, which catalyzes the electron acceptor-dependent oxidation of the intermediate stigmast-1,4-diene-3-one to a conjugated (22,24)-diene. We suggest an α4β4 architecture of the 440 kDa enzyme, with each subunit covalently binding an flavin mononucleotide cofactor to a histidyl residue. As isolated, both flavins are present as red semiquinone radicals, which can be reduced by stigmast-1,4-diene-3-one but cannot be oxidized even with strong oxidizing agents. We propose a mechanism involving an allylic radical intermediate in which two flavin semiquinones each abstract one hydrogen atom from the substrate. The conjugated delta-22,24 moiety formed allows for the subsequent hydroxylation of the terminal C26 with water by a heterologously produced molybdenum-dependent steroid C26 dehydrogenase 2. In conclusion, the pathway elucidated for delta-22 steroids achieves oxygen-independent hydroxylation of the isoprenoid side chain by bypassing the ATP-dependent formation of a phosphorylated intermediate.
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Affiliation(s)
- Tingyi Zhan
- Faculty of Biology, Department of Microbiology, University of Freiburg, Freiburg, Germany
| | - Christian Jacoby
- Faculty of Biology, Department of Microbiology, University of Freiburg, Freiburg, Germany
| | - Martin Jede
- Faculty of Biology, Department of Microbiology, University of Freiburg, Freiburg, Germany
| | - Bettina Knapp
- Faculty of Biology, Department of Biochemistry and Functional Proteomics, University of Freiburg, Freiburg, Germany
| | - Sascha Ferlaino
- Institute of Pharmaceutical Sciences, University of Freiburg, Freiburg, Germany
| | - Andreas Günter
- Institute of Physical Chemistry, University of Freiburg, Freiburg, Germany
| | - Friedel Drepper
- Faculty of Biology, Department of Biochemistry and Functional Proteomics, University of Freiburg, Freiburg, Germany
| | - Michael Müller
- Institute of Pharmaceutical Sciences, University of Freiburg, Freiburg, Germany
| | - Stefan Weber
- Institute of Physical Chemistry, University of Freiburg, Freiburg, Germany
| | - Matthias Boll
- Faculty of Biology, Department of Microbiology, University of Freiburg, Freiburg, Germany.
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3
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Kosian D, Willistein M, Weßbecher R, Eggers C, May O, Boll M. Highly selective whole-cell 25-hydroxyvitamin D 3 synthesis using molybdenum-dependent C25-steroid dehydrogenase and cyclodextrin recycling. Microb Cell Fact 2024; 23:30. [PMID: 38245746 PMCID: PMC10799449 DOI: 10.1186/s12934-024-02303-6] [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] [Received: 11/14/2023] [Accepted: 01/12/2024] [Indexed: 01/22/2024] Open
Abstract
BACKGROUND The global prevalence of vitamin D (VitD) deficiency associated with numerous acute and chronic diseases has led to strategies to improve the VitD status through dietary intake of VitD-fortified foods and VitD supplementation. In this context, the circulating form of VitD3 (cholecalciferol) in the human body, 25-hydroxy-VitD3 (calcifediol, 25OHVitD3), has a much higher efficacy in improving the VitD status, which has motivated researchers to develop methods for its effective and sustainable synthesis. Conventional monooxygenase-/peroxygenase-based biocatalytic platforms for the conversion of VitD3 to value-added 25OHVitD3 are generally limited by a low selectivity and yield, costly reliance on cyclodextrins and electron donor systems, or by the use of toxic co-substrates. RESULTS In this study, we used a whole-cell approach for biocatalytic 25OHVitD3 synthesis, in which a molybdenum-dependent steroid C25 dehydrogenase was produced in the denitrifying bacterium Thauera aromatica under semi-aerobic conditions, where the activity of the enzyme remained stable. This enzyme uses water as a highly selective VitD3 hydroxylating agent and is independent of an electron donor system. High density suspensions of resting cells producing steroid C25 dehydrogenase catalysed the conversion of VitD3 to 25OHVitD3 using either O2 via the endogenous respiratory chain or externally added ferricyanide as low cost electron acceptor. The maximum 25OHVitD3 titer achieved was 1.85 g L-1 within 50 h with a yield of 99%, which is 2.2 times higher than the highest reported value obtained with previous biocatalytic systems. In addition, we developed a simple method for the recycling of the costly VitD3 solubiliser cyclodextrin, which could be reused for 10 reaction cycles without a significant loss of quality or quantity. CONCLUSIONS The established steroid C25 dehydrogenase-based whole-cell system for the value-adding conversion of VitD3 to 25OHVitD3 offers a number of advantages in comparison to conventional oxygenase-/peroxygenase-based systems including its high selectivity, independence from an electron donor system, and the higher product titer and yield. Together with the established cyclodextrin recycling procedure, the established system provides an attractive platform for large-scale 25OHVitD3 synthesis.
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Affiliation(s)
- Dennis Kosian
- Faculty of Biology - Microbiology, University of Freiburg, 79104, Freiburg, Germany
| | - Max Willistein
- Faculty of Biology - Microbiology, University of Freiburg, 79104, Freiburg, Germany
| | - Ralf Weßbecher
- Faculty of Biology - Microbiology, University of Freiburg, 79104, Freiburg, Germany
| | - Constantin Eggers
- Faculty of Biology - Microbiology, University of Freiburg, 79104, Freiburg, Germany
| | - Oliver May
- DSM Nutritional Products, Koninklijke DSM N.V., Kaiseraugst, 4303, Switzerland
| | - Matthias Boll
- Faculty of Biology - Microbiology, University of Freiburg, 79104, Freiburg, Germany.
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Wohlgemuth R. Synthesis of Metabolites and Metabolite-like Compounds Using Biocatalytic Systems. Metabolites 2023; 13:1097. [PMID: 37887422 PMCID: PMC10608848 DOI: 10.3390/metabo13101097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Revised: 10/13/2023] [Accepted: 10/15/2023] [Indexed: 10/28/2023] Open
Abstract
Methodologies for the synthesis and purification of metabolites, which have been developed following their discovery, analysis, and structural identification, have been involved in numerous life science milestones. The renewed focus on the small molecule domain of biological cells has also created an increasing awareness of the rising gap between the metabolites identified and the metabolites which have been prepared as pure compounds. The design and engineering of resource-efficient and straightforward synthetic methodologies for the production of the diverse and numerous metabolites and metabolite-like compounds have attracted much interest. The variety of metabolic pathways in biological cells provides a wonderful blueprint for designing simplified and resource-efficient synthetic routes to desired metabolites. Therefore, biocatalytic systems have become key enabling tools for the synthesis of an increasing number of metabolites, which can then be utilized as standards, enzyme substrates, inhibitors, or other products, or for the discovery of novel biological functions.
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Affiliation(s)
- Roland Wohlgemuth
- MITR, Institute of Applied Radiation Chemistry, Faculty of Chemistry, Lodz University of Technology, Zeromskiego Street 116, 90-924 Lodz, Poland;
- Swiss Coordination Committee Biotechnology (SKB), 8021 Zurich, Switzerland
- European Society of Applied Biocatalysis (ESAB), 1000 Brussels, Belgium
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Abbas AM, Elkhatib WF, Aboulwafa MM, Hassouna NA, Aboshanab KM. Bioconversion of vitamin D 3 into calcitriol by Actinomyces hyovaginalis isolate CCASU- A11-2. AMB Express 2023; 13:73. [PMID: 37434090 DOI: 10.1186/s13568-023-01574-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2023] [Accepted: 06/20/2023] [Indexed: 07/13/2023] Open
Abstract
Vitamin D3 is a fat-soluble prohormone that is activated inside the liver to produce 25-hydroxyvitamin D3 (calcidiol), and in the kidney to produce the fully active 1α, 25-dihydroxy vitamin D3 (calcitriol). A previous work piloted in our laboratory, resulted in a successful recovery of a local soil-promising Actinomyces hyovaginalis isolate CCASU-A11-2 capable of converting vitamin D3 into calcitriol. Despite the rising amount of research on vitamin D3 bioconversion into calcitriol, further deliberate studies on this topic can significantly contribute to the improvement of such a bioconversion process. Therefore, this work aimed to improve the bioconversion process, using the study isolate, in a 14 L laboratory fermenter (4 L fermentation medium composed of fructose (15 g/L), defatted soybean (15 g/L), NaCl (5 g/L), CaCO3 2 g/L); K2HPO4, (1 g/L) NaF (0.5 g/L) and initial of pH 7.8) where different experiments were undertaken to investigate the effect of different culture conditions on the bioconversion process. Using the 14 L laboratory fermenter, the calcitriol production was increased by about 2.5-fold (32.8 µg/100 mL) to that obtained in the shake flask (12.4 µg/100 mL). The optimal bioconversion conditions were inoculum size of 2% v/v, agitation rate of 200 rpm, aeration rate of 1 vvm, initial pH of 7.8 (uncontrolled); addition of vitamin D3 (substrate) 48 h after the start of the main culture. In conclusion, the bioconversion of vitamin D3 into calcitriol in a laboratory fermenter showed a 2.5-fold increase as compared to the shake flask level where, the important factors influencing the bioconversion process were the aeration rate, inoculum size, the timing of substrate addition, and the fixed pH of the fermentation medium. So, those factors should be critically considered for the scaling-up of the biotransformation process.
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Affiliation(s)
- Ahmad M Abbas
- Department of Microbiology and Immunology, Faculty of Pharmacy, Ain Shams University, African Union Organization St. Abbassia, Cairo, 11566, Egypt
- Department of Microbiology & Immunology, Faculty of Pharmacy, King Salman International University, South Sinai, Egypt
| | - Walid F Elkhatib
- Department of Microbiology and Immunology, Faculty of Pharmacy, Ain Shams University, African Union Organization St. Abbassia, Cairo, 11566, Egypt
- Department of Microbiology & Immunology, Faculty of Pharmacy, Galala University, New Galala city, Suez, Egypt
| | - Mohammad M Aboulwafa
- Department of Microbiology and Immunology, Faculty of Pharmacy, Ain Shams University, African Union Organization St. Abbassia, Cairo, 11566, Egypt
- Department of Microbiology & Immunology, Faculty of Pharmacy, King Salman International University, South Sinai, Egypt
| | - Nadia A Hassouna
- Department of Microbiology and Immunology, Faculty of Pharmacy, Ain Shams University, African Union Organization St. Abbassia, Cairo, 11566, Egypt
| | - Khaled M Aboshanab
- Department of Microbiology and Immunology, Faculty of Pharmacy, Ain Shams University, African Union Organization St. Abbassia, Cairo, 11566, Egypt.
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Wei W, Gao S, Yi Q, Liu A, Yu S, Zhou J. Reengineering of 7-dehydrocholesterol biosynthesis in Saccharomyces cerevisiae using combined pathway and organelle strategies. Front Microbiol 2022; 13:978074. [PMID: 36016783 PMCID: PMC9398459 DOI: 10.3389/fmicb.2022.978074] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2022] [Accepted: 07/21/2022] [Indexed: 11/13/2022] Open
Abstract
7-Dehydrocholesterol (7-DHC) is a widely used sterol and a precursor of several costly steroidal drugs. In this study, 7-DHC biosynthesis pathway was constructed and modified in Saccharomyces cerevisiae. Firstly, the biosynthesis pathway was constructed by knocking out the competitive pathway genes ERG5 and ERG6 and integrating two DHCR24 copies from Gallus gallus at both sites. Then, 7-DHC titer was improved by knocking out MOT3, which encoded a transcriptional repressor for the 7-DHC biosynthesis pathway. Next, by knocking out NEM1 and PAH1, 7-DHC accumulation was improved, and genes upregulation was verified by quantitative PCR (qPCR). Additionally, tHMG1, IDI1, ERG2, ERG3, DHCR24, POS5, and CTT1 integration into multi-copy sites was used to convert precursors to 7-DHC, and increase metabolic flux. Finally, qPCR confirmed the significant up-regulation of key genes transcriptional levels. In a 96 h shaker flask fermentation, the 7-DHC titer was 649.5 mg/L by de novo synthesis. In a 5 L bioreactor, the 7-DHC titer was 2.0 g/L, which was the highest 7-DHC titer reported to date. Our study is of great significance for the industrial production of 7-DHC and steroid development for medical settings.
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Affiliation(s)
- Wenqian Wei
- Engineering Research Center of Ministry of Education on Food Synthetic Biotechnology, and School of Biotechnology, Jiangnan University, Wuxi, China
- Science Center for Future Foods, School of Biotechnology, Jiangnan University, Wuxi, China
| | - Song Gao
- Engineering Research Center of Ministry of Education on Food Synthetic Biotechnology, and School of Biotechnology, Jiangnan University, Wuxi, China
- Science Center for Future Foods, School of Biotechnology, Jiangnan University, Wuxi, China
| | - Qiong Yi
- Changsha Hospital for Maternal & Child Health Care, Changsha, China
| | - Anjian Liu
- Hunan Kerey Pharmaceutical Co., Ltd., Shaoyang, China
| | - Shiqin Yu
- Engineering Research Center of Ministry of Education on Food Synthetic Biotechnology, and School of Biotechnology, Jiangnan University, Wuxi, China
- Science Center for Future Foods, School of Biotechnology, Jiangnan University, Wuxi, China
| | - Jingwen Zhou
- Engineering Research Center of Ministry of Education on Food Synthetic Biotechnology, and School of Biotechnology, Jiangnan University, Wuxi, China
- Science Center for Future Foods, School of Biotechnology, Jiangnan University, Wuxi, China
- Jiangsu Provisional Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi, China
- *Correspondence: Jingwen Zhou,
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7
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Nandy A, Adamji H, Kastner DW, Vennelakanti V, Nazemi A, Liu M, Kulik HJ. Using Computational Chemistry To Reveal Nature’s Blueprints for Single-Site Catalysis of C–H Activation. ACS Catal 2022. [DOI: 10.1021/acscatal.2c02096] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Aditya Nandy
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Husain Adamji
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - David W. Kastner
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Vyshnavi Vennelakanti
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Azadeh Nazemi
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Mingjie Liu
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Heather J. Kulik
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
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8
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Kõllo M, Kasari M, Kasari V, Pehk T, Järving I, Lopp M, Jõers A, Kanger T. Designed whole-cell-catalysis-assisted synthesis of 9,11-secosterols. Beilstein J Org Chem 2021; 17:581-588. [PMID: 33747232 PMCID: PMC7940815 DOI: 10.3762/bjoc.17.52] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Accepted: 02/17/2021] [Indexed: 01/29/2023] Open
Abstract
A method for the synthesis of 9,11-secosteroids starting from the natural corticosteroid cortisol is described. There are two key steps in this approach, combining chemistry and synthetic biology. Stereo- and regioselective hydroxylation at C9 (steroid numbering) is carried out using whole-cell biocatalysis, followed by the chemical cleavage of the C-C bond of the vicinal diol. The two-step method features mild reaction conditions and completely excludes the use of toxic oxidants.
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Affiliation(s)
- Marek Kõllo
- Department of Chemistry and Biotechnology, School of Science, Tallinn University of Technology, Akadeemia tee 15, 12618 Tallinn, Estonia
| | - Marje Kasari
- Institute of Technology, University of Tartu, Nooruse 1, 50104 Tartu, Estonia
| | - Villu Kasari
- Institute of Technology, University of Tartu, Nooruse 1, 50104 Tartu, Estonia
| | - Tõnis Pehk
- National Institute of Chemical Physics and Biophysics, Akadeemia tee 23, 12618 Tallinn, Estonia
| | - Ivar Järving
- Department of Chemistry and Biotechnology, School of Science, Tallinn University of Technology, Akadeemia tee 15, 12618 Tallinn, Estonia
| | - Margus Lopp
- Department of Chemistry and Biotechnology, School of Science, Tallinn University of Technology, Akadeemia tee 15, 12618 Tallinn, Estonia
| | - Arvi Jõers
- Institute of Technology, University of Tartu, Nooruse 1, 50104 Tartu, Estonia
| | - Tõnis Kanger
- Department of Chemistry and Biotechnology, School of Science, Tallinn University of Technology, Akadeemia tee 15, 12618 Tallinn, Estonia
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9
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Jacoby C, Ferlaino S, Bezold D, Jessen H, Müller M, Boll M. ATP-dependent hydroxylation of an unactivated primary carbon with water. Nat Commun 2020; 11:3906. [PMID: 32764563 PMCID: PMC7411048 DOI: 10.1038/s41467-020-17675-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Accepted: 07/09/2020] [Indexed: 11/09/2022] Open
Abstract
Enzymatic hydroxylation of unactivated primary carbons is generally associated with the use of molecular oxygen as co-substrate for monooxygenases. However, in anaerobic cholesterol-degrading bacteria such as Sterolibacterium denitrificans the primary carbon of the isoprenoid side chain is oxidised to a carboxylate in the absence of oxygen. Here, we identify an enzymatic reaction sequence comprising two molybdenum-dependent hydroxylases and one ATP-dependent dehydratase that accomplish the hydroxylation of unactivated primary C26 methyl group of cholesterol with water: (i) hydroxylation of C25 to a tertiary alcohol, (ii) ATP-dependent dehydration to an alkene via a phosphorylated intermediate, (iii) hydroxylation of C26 to an allylic alcohol that is subsequently oxidised to the carboxylate. The three-step enzymatic reaction cascade divides the high activation energy barrier of primary C–H bond cleavage into three biologically feasible steps. This finding expands our knowledge of biological C–H activations beyond canonical oxygenase-dependent reactions. Monooxygenases catalyse the hydroxylation of C-H bonds using oxygen as a co-substrate, which, in turn, is unavailable for anaerobic bacteria. Here, the authors report a three-step reaction cascade involving two hydroxylases and one dehydratase which hydroxylate the C26 methyl group of cholesterol with water as a co-substrate.
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Affiliation(s)
- Christian Jacoby
- Microbiology, Faculty of Biology, Albert-Ludwigs-Universität Freiburg, Schänzlestr. 1, 79104, Freiburg, Germany
| | - Sascha Ferlaino
- Institute of Pharmaceutical Sciences, Albert-Ludwigs-Universität Freiburg, Albertstrasse 25, 79104, Freiburg, Germany
| | - Dominik Bezold
- Institute of Organic Chemistry, Albert-Ludwigs-Universität Freiburg, Albertstrasse 21, 79104, Freiburg, Germany
| | - Henning Jessen
- Institute of Organic Chemistry, Albert-Ludwigs-Universität Freiburg, Albertstrasse 21, 79104, Freiburg, Germany
| | - Michael Müller
- Institute of Pharmaceutical Sciences, Albert-Ludwigs-Universität Freiburg, Albertstrasse 25, 79104, Freiburg, Germany
| | - Matthias Boll
- Microbiology, Faculty of Biology, Albert-Ludwigs-Universität Freiburg, Schänzlestr. 1, 79104, Freiburg, Germany.
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10
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Tang D, Liu W, Huang L, Cheng L, Xu Z. Efficient biotransformation of vitamin D 3 to 25-hydroxyvitamin D 3 by a newly isolated Bacillus cereus strain. Appl Microbiol Biotechnol 2019; 104:765-774. [PMID: 31776608 DOI: 10.1007/s00253-019-10250-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Revised: 10/24/2019] [Accepted: 11/05/2019] [Indexed: 02/07/2023]
Abstract
25-hydroxyvitamin D3 has attracted considerable attention due to its great medical value and huge market demand in animal husbandry. Microbial production of 25-hydroxyvitamin D3 has been recognized as an alternative superior to traditional chemical synthesis. In this study, a Gram-positive bacteria zju 4-2 (CCTCC M 2019385) was isolated from the soil using vitamin D3 as the sole carbon source and was identified as Bacillus cereus according to its physiological characteristics and 16S rRNA analysis, which also showed a relatively high capacity for 25-hydroxyvitamin D3 production. Through systematic optimization of different catalytic conditions, the optimal solvent system of vitamin D3, vitamin D3 addition time and concentration, temperature, and pH were shown to be propylene glycol/ethanol (v/v = 9:1), early stationary phase, 2 g/L, 37 °C, and pH 7.2, respectively. With these optimal conditions, 796 mg/L of 25-hydroxyvitamin D3 was achieved after 48 h bioconversion with zju 4-2 at the shake flask level. Finally, up to 830 mg/L 25-hydroxyvitamin D3 with a yield of 41.5% was obtained in a 5 L fermentation tank. Our developed biotransformation process with this newly isolated strain provides a platform to produce 25-hydroxyvitamin D3 efficiently at industrialization scale.
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Affiliation(s)
- Dandan Tang
- State Key Laboratory of Clean Energy Utilization, College of Energy Engineering, Zhejiang University, Hangzhou, 310027, China.,Key Laboratory of Biomass Chemical Engineering (Education Ministry), College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Wei Liu
- Key Laboratory of Biomass Chemical Engineering (Education Ministry), College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Lei Huang
- Key Laboratory of Biomass Chemical Engineering (Education Ministry), College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Leming Cheng
- State Key Laboratory of Clean Energy Utilization, College of Energy Engineering, Zhejiang University, Hangzhou, 310027, China.
| | - Zhinan Xu
- Key Laboratory of Biomass Chemical Engineering (Education Ministry), College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China.
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11
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Szaleniec M, Wojtkiewicz AM, Bernhardt R, Borowski T, Donova M. Bacterial steroid hydroxylases: enzyme classes, their functions and comparison of their catalytic mechanisms. Appl Microbiol Biotechnol 2018; 102:8153-8171. [PMID: 30032434 PMCID: PMC6153880 DOI: 10.1007/s00253-018-9239-3] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Revised: 07/10/2018] [Accepted: 07/10/2018] [Indexed: 12/22/2022]
Abstract
The steroid superfamily includes a wide range of compounds that are essential for living organisms of the animal and plant kingdoms. Structural modifications of steroids highly affect their biological activity. In this review, we focus on hydroxylation of steroids by bacterial hydroxylases, which take part in steroid catabolic pathways and play an important role in steroid degradation. We compare three distinct classes of metalloenzymes responsible for aerobic or anaerobic hydroxylation of steroids, namely: cytochrome P450, Rieske-type monooxygenase 3-ketosteroid 9α-hydroxylase, and molybdenum-containing steroid C25 dehydrogenases. We analyze the available literature data on reactivity, regioselectivity, and potential application of these enzymes in organic synthesis of hydroxysteroids. Moreover, we describe mechanistic hypotheses proposed for all three classes of enzymes along with experimental and theoretical evidences, which have provided grounds for their formulation. In case of the 3-ketosteroid 9α-hydroxylase, such a mechanistic hypothesis is formulated for the first time in the literature based on studies conducted for other Rieske monooxygenases. Finally, we provide comparative analysis of similarities and differences in the reaction mechanisms utilized by bacterial steroid hydroxylases.
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Affiliation(s)
- Maciej Szaleniec
- Jerzy Haber Institute of Catalysis and Surface Chemistry, Polish Academy of Sciences, Niezapominajek 8, 30-239, Kraków, Poland.
| | - Agnieszka M Wojtkiewicz
- Jerzy Haber Institute of Catalysis and Surface Chemistry, Polish Academy of Sciences, Niezapominajek 8, 30-239, Kraków, Poland
| | - Rita Bernhardt
- Lehrstuhl für Biochemie, Universität des Saarlandes, Campus B2 2, 66123, Saarbrücken, Germany
| | - Tomasz Borowski
- Jerzy Haber Institute of Catalysis and Surface Chemistry, Polish Academy of Sciences, Niezapominajek 8, 30-239, Kraków, Poland
| | - Marina Donova
- G.K. Skryabin Institute of Biochemistry and Physiology of Microorganisms, Russian Academy of Sciences, Pushchino, Moscow Oblast, 142290, Russia
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12
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Four Molybdenum-Dependent Steroid C-25 Hydroxylases: Heterologous Overproduction, Role in Steroid Degradation, and Application for 25-Hydroxyvitamin D 3 Synthesis. mBio 2018; 9:mBio.00694-18. [PMID: 29921665 PMCID: PMC6016249 DOI: 10.1128/mbio.00694-18] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Side chain-containing steroids are ubiquitous constituents of biological membranes that are persistent to biodegradation. Aerobic, steroid-degrading bacteria employ oxygenases for isoprenoid side chain and tetracyclic steran ring cleavage. In contrast, a Mo-containing steroid C-25 dehydrogenase (S25DH) of the dimethyl sulfoxide (DMSO) reductase family catalyzes the oxygen-independent hydroxylation of tertiary C-25 in the anaerobic, cholesterol-degrading bacterium Sterolibacterium denitrificans Its genome contains eight paralogous genes encoding active site α-subunits of putative S25DH-like proteins. The difficult enrichment of labile, oxygen-sensitive S25DH from the wild-type bacteria and the inability of its active heterologous production have largely hampered the study of S25DH-like gene products. Here we established a heterologous expression platform for the three structural genes of S25DH subunits together with an essential chaperone in the denitrifying betaproteobacterium Thauera aromatica K172. Using this system, S25DH1 and three isoenzymes (S25DH2, S25DH3, and S25DH4) were overproduced in a soluble, active form allowing a straightforward purification of nontagged αβγ complexes. All S25DHs contained molybdenum, four [4Fe-4S] clusters, one [3Fe-4S] cluster, and heme B and catalyzed the specific, water-dependent C-25 hydroxylations of various 4-en-3-one forms of phytosterols and zoosterols. Crude extracts from T. aromatica expressing genes encoding S25DH1 catalyzed the hydroxylation of vitamin D3 (VD3) to the clinically relevant 25-OH-VD3 with >95% yield at a rate 6.5-fold higher than that of wild-type bacterial extracts; the specific activity of recombinant S25DH1 was twofold higher than that of wild-type enzyme. These results demonstrate the potential application of the established expression platform for 25-OH-VD3 synthesis and pave the way for the characterization of previously genetically inaccessible S25DH-like Mo enzymes of the DMSO reductase family.IMPORTANCE Steroids are ubiquitous bioactive compounds, some of which are considered an emerging class of micropollutants. Their degradation by microorganisms is the major process of steroid elimination from the environment. While oxygenase-dependent steroid degradation in aerobes has been studied for more than 40 years, initial insights into the anoxic steroid degradation have only recently been obtained. Molybdenum-dependent steroid C25 dehydrogenases (S25DHs) have been proposed to catalyze oxygen-independent side chain hydroxylations of globally abundant zoo-, phyto-, and mycosterols; however, so far, their lability has allowed only the initial characterization of a single S25DH. Here we report on a heterologous gene expression platform that allowed for easy isolation and characterization of four highly active S25DH isoenzymes. The results obtained demonstrate the key role of S25DHs during anoxic degradation of various steroids. Moreover, the platform is valuable for the efficient enzymatic hydroxylation of vitamin D3 to its clinically relevant C-25-OH form.
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13
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Kalimuthu P, Wojtkiewicz AM, Szaleniec M, Bernhardt PV. Electrocatalytic Hydroxylation of Sterols by Steroid C25 Dehydrogenase from Sterolibacterium denitrificans. Chemistry 2018; 24:7710-7717. [PMID: 29573289 DOI: 10.1002/chem.201800616] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Revised: 03/22/2018] [Indexed: 12/20/2022]
Abstract
The electrochemically driven catalysis of the complex molybdoenzyme steroid C25 dehydrogenase (S25DH) from the β-Proteobacterium Sterolibacterium denitrificans is reported. S25DH catalyses the oxygen-independent regioselective hydroxylation of the tertiary C25 atom of sterols and also their derivatives. Cholest-4-en-3-one is a native substrate for S25DH, which produces 25-hydroxycholest-4-en-3-one as a product of catalytic turnover. Cholecalciferol (vitD3 ) is also a substrate. S25DH was immobilised on a modified gold working electrode with the co-adsorbent chitosan. The complexes ferricyanide ([Fe(CN)6 ]3- ) and ferrocenium methanol (FM+ ) are effective artificial electron acceptors from S25DH and act as mediators of electron transfer between the electrode and the enzyme. 2-Hydroxypropyl-β-cyclodextrin (HPCD) was employed as a sterol solubiliser, in addition to 2-methoxyethanol. The catalytic activity varied, depending upon the concentration of solubiliser in the reaction mixture. Parallel studies with [Fe(CN)6 ]3- as a chemical (as opposed to electrochemical) oxidant coupled to HPLC analysis show that S25DH is capable of oxidising both vitD3 and its less stable isomer, pre-vitD3 , and that the former substrate is stabilised by HPCD.
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Affiliation(s)
- Palraj Kalimuthu
- School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane, 4072, Australia
| | - Agnieszka M Wojtkiewicz
- Jerzy Haber Institute of Catalysis and Surface Chemistry, Polish Academy of Sciences, ul. Niezapominajek 8, 30 239, Krakow, Poland
| | - Maciej Szaleniec
- Jerzy Haber Institute of Catalysis and Surface Chemistry, Polish Academy of Sciences, ul. Niezapominajek 8, 30 239, Krakow, Poland
| | - Paul V Bernhardt
- School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane, 4072, Australia
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14
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Functional Characterization of Three Specific Acyl-Coenzyme A Synthetases Involved in Anaerobic Cholesterol Degradation in Sterolibacterium denitrificans Chol1S. Appl Environ Microbiol 2018; 84:AEM.02721-17. [PMID: 29374035 DOI: 10.1128/aem.02721-17] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2017] [Accepted: 01/21/2018] [Indexed: 12/28/2022] Open
Abstract
The denitrifying betaproteobacterium Sterolibacterium denitrificans Chol1S catabolizes steroids such as cholesterol via an oxygen-independent pathway. It involves enzyme reaction sequences described for aerobic cholesterol and bile acid degradation as well as enzymes uniquely found in anaerobic steroid-degrading bacteria. Recent studies provided evidence that in S. denitrificans, the cholest-4-en-3-one intermediate is oxygen-independently oxidized to Δ4-dafachronic acid (C26-oic acid), which is subsequently activated by a substrate-specific acyl-coenzyme A (acyl-CoA) synthetase (ACS). Further degradation was suggested to proceed via unconventional β-oxidation, where aldolases, aldehyde dehydrogenases, and additional ACSs substitute for classical β-hydroxyacyl-CoA dehydrogenases and thiolases. Here, we heterologously expressed three cholesterol-induced genes that putatively code for AMP-forming ACSs and characterized two of the products as specific 3β-hydroxy-Δ5-cholenoyl-CoA (C24-oic acid)- and pregn-4-en-3-one-22-oyl-CoA (C22-oic acid)-forming ACSs, respectively. A third heterologously produced ATP-dependent ACS was inactive with C26-, C24-, or C22-oic-acids but activated 3aα-H-4α-(3'propanoate)-7aβ-methylhexahydro-1,5-indanedione (HIP) to HIP-CoA, a rather late intermediate of aerobic cholesterol degradation that still contains the CD rings of the sterane skeleton. This work provides experimental evidence that anaerobic steroid degradation proceeds via numerous alternate CoA-ester-dependent or -independent enzymatic reaction sequences as a result of aldolytic side chain and hydrolytic sterane ring C-C bond cleavages. The aldolytic side chain degradation pathway comprising highly exergonic ACSs and aldehyde dehydrogenases is considered to be essential for driving the unfavorable oxygen-independent C26 hydroxylation forward.IMPORTANCE The biological degradation of ubiquitously abundant steroids is hampered by their low solubility and the presence of two quaternary carbon atoms. The degradation of cholesterol by aerobic Actinobacteria has been studied in detail for more than 30 years and involves a number of oxygenase-dependent reactions. In contrast, much less is known about the oxygen-independent degradation of steroids in denitrifying bacteria. In the cholesterol-degrading anaerobic model organism Sterolibacterium denitrificans Chol1S, initial evidence has been obtained that steroid degradation proceeds via numerous alternate coenzyme A (CoA)-ester-dependent/independent reaction sequences. Here, we describe the heterologous expression of three highly specific and characteristic acyl-CoA synthetases, two of which play key roles in the degradation of the side chain, whereas a third one is specifically involved in the B ring degradation. The results obtained shed light into oxygen-independent steroid degradation comprising more than 40 enzymatic reactions.
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15
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Warnke M, Jacoby C, Jung T, Agne M, Mergelsberg M, Starke R, Jehmlich N, von Bergen M, Richnow HH, Brüls T, Boll M. A patchwork pathway for oxygenase-independent degradation of side chain containing steroids. Environ Microbiol 2017; 19:4684-4699. [PMID: 28940833 DOI: 10.1111/1462-2920.13933] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Revised: 09/11/2017] [Accepted: 09/14/2017] [Indexed: 12/22/2022]
Abstract
The denitrifying betaproteobacterium Sterolibacterium denitrificans serves as model organism for studying the oxygen-independent degradation of cholesterol. Here, we demonstrate its capability of degrading various globally abundant side chain containing zoo-, phyto- and mycosterols. We provide the complete genome that empowered an integrated genomics/proteomics/metabolomics approach, accompanied by the characterization of a characteristic enzyme of steroid side chain degradation. The results indicate that individual molybdopterin-containing steroid dehydrogenases are involved in C25-hydroxylations of steroids with different isoprenoid side chains, followed by the unusual conversion to C26-oic acids. Side chain degradation to androsta-1,4-diene-3,17-dione (ADD) via aldolytic C-C bond cleavages involves acyl-CoA synthetases/dehydrogenases specific for the respective 26-, 24- and 22-oic acids/-oyl-CoAs and promiscuous MaoC-like enoyl-CoA hydratases, aldolases and aldehyde dehydrogenases. Degradation of rings A and B depends on gene products uniquely found in anaerobic steroid degraders, which after hydrolytic cleavage of ring A, again involves CoA-ester intermediates. The degradation of the remaining CD rings via hydrolytic cleavage appears to be highly similar in aerobic and anaerobic bacteria. Anaerobic cholesterol degradation employs a composite repertoire of more than 40 genes partially known from aerobic degradation in gammaproteobacteria/actinobacteria, supplemented by unique genes that are required to circumvent oxygenase-dependent reactions.
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Affiliation(s)
- Markus Warnke
- Institute of Biology II, Microbiology, Albert-Ludwigs-University Freiburg, Freiburg, Germany
| | - Christian Jacoby
- Institute of Biology II, Microbiology, Albert-Ludwigs-University Freiburg, Freiburg, Germany
| | - Tobias Jung
- Institute of Biology II, Microbiology, Albert-Ludwigs-University Freiburg, Freiburg, Germany
| | - Michael Agne
- Institute of Biology II, Microbiology, Albert-Ludwigs-University Freiburg, Freiburg, Germany.,Spemann Graduate School of Biology and Medicine (SGBM), Albert-Ludwigs-University Freiburg, Freiburg, Germany
| | - Mario Mergelsberg
- Institute of Biology II, Microbiology, Albert-Ludwigs-University Freiburg, Freiburg, Germany
| | - Robert Starke
- Department of Molecular Systems Biology, Helmholtz Centre of Environmental Sciences, Leipzig, Germany
| | - Nico Jehmlich
- Department of Molecular Systems Biology, Helmholtz Centre of Environmental Sciences, Leipzig, Germany
| | - Martin von Bergen
- Department of Molecular Systems Biology, Helmholtz Centre of Environmental Sciences, Leipzig, Germany.,Institute of Biochemistry, Faculty of Biosciences, Pharmacy and Psychology, University of Leipzig, Leipzig, Germany
| | - Hans-Hermann Richnow
- Department of Isotope Biogeochemistry, Helmholtz Centre of Environmental Sciences, Leipzig, Germany
| | - Thomas Brüls
- CEA, DRF, IG, Genoscope, Evry, France.,CNRS-UMR8030, Université d'Evry Val d'Essonne and Université Paris-Saclay, Evry, France
| | - Matthias Boll
- Institute of Biology II, Microbiology, Albert-Ludwigs-University Freiburg, Freiburg, Germany
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16
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Rugor A, Wójcik-Augustyn A, Niedzialkowska E, Mordalski S, Staroń J, Bojarski A, Szaleniec M. Reaction mechanism of sterol hydroxylation by steroid C25 dehydrogenase - Homology model, reactivity and isoenzymatic diversity. J Inorg Biochem 2017; 173:28-43. [PMID: 28482186 DOI: 10.1016/j.jinorgbio.2017.04.027] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Revised: 04/24/2017] [Accepted: 04/26/2017] [Indexed: 11/29/2022]
Abstract
Steroid C25 dehydrogenase (S25DH) is a molybdenum-containing oxidoreductase isolated from the anaerobic Sterolibacterium denitrificans Chol-1S. S25DH is classified as 'EBDH-like' enzyme (EBDH, ethylbenzene dehydrogenase) and catalyzes the introduction of an OH group to the C25 atom of a sterol aliphatic side-chain. Due to its regioselectivity, S25DH is proposed as a catalyst in production of pharmaceuticals: calcifediol or 25-hydroxycholesterol. The aim of presented research was to obtain structural model of catalytic subunit α and investigate the reaction mechanism of the O2-independent tertiary carbon atom activation. Based on homology modeling and theoretical calculations, a S25DH α subunit model was for the first time characterized and compared to other S25DH-like isoforms. The molecular dynamics simulations of the enzyme-substrate complexes revealed two stable binding modes of a substrate, which are stabilized predominantly by van der Waals forces in the hydrophobic substrate channel. However, H-bond interactions involving polar residues with C3=O/C3-OH in the steroid ring appear to be responsible for positioning the substrate. These results may explain the experimental kinetic results which showed that 3-ketosterols are hydroxylated 5-10-fold faster than 3-hydroxysterols. The reaction mechanism was studied using QM:MM and QM-only cluster models. The postulated mechanism involves homolytic CH cleavage by the MoO ligand, giving rise to a radical intermediate with product obtained in an OH rebound process. The hypothesis was supported by kinetic isotopic effect (KIE) experiments involving 25,26,26,26-[2H]-cholesterol (4.5) and the theoretically predicted intrinsic KIE (7.0-7.2). Finally, we have demonstrated that the recombinant S25DH-like isoform catalyzes the same reaction as S25DH.
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Affiliation(s)
- Agnieszka Rugor
- Jerzy Haber Institute of Catalysis and Surface Chemistry, Polish Academy of Sciences, Krakow, Poland
| | - Anna Wójcik-Augustyn
- Department of Computational Biophysics and Bioinformatics, Faculty of Biochemistry, Biophysics and Biotechnology, JU, Krakow, Poland
| | - Ewa Niedzialkowska
- Jerzy Haber Institute of Catalysis and Surface Chemistry, Polish Academy of Sciences, Krakow, Poland
| | - Stefan Mordalski
- Institute of Pharmacology, Polish Academy of Sciences, Krakow, Poland
| | - Jakub Staroń
- Jerzy Haber Institute of Catalysis and Surface Chemistry, Polish Academy of Sciences, Krakow, Poland; Institute of Pharmacology, Polish Academy of Sciences, Krakow, Poland
| | - Andrzej Bojarski
- Institute of Pharmacology, Polish Academy of Sciences, Krakow, Poland
| | - Maciej Szaleniec
- Jerzy Haber Institute of Catalysis and Surface Chemistry, Polish Academy of Sciences, Krakow, Poland.
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17
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Niedzialkowska E, Mrugała B, Rugor A, Czub MP, Skotnicka A, Cotelesage JJH, George GN, Szaleniec M, Minor W, Lewiński K. Optimization of overexpression of a chaperone protein of steroid C25 dehydrogenase for biochemical and biophysical characterization. Protein Expr Purif 2017; 134:47-62. [PMID: 28343996 DOI: 10.1016/j.pep.2017.03.019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Revised: 03/02/2017] [Accepted: 03/21/2017] [Indexed: 11/27/2022]
Abstract
Molybdenum is an essential nutrient for metabolism in plant, bacteria, and animals. Molybdoenzymes are involved in nitrogen assimilation and oxidoreductive detoxification, and bioconversion reactions of environmental, industrial, and pharmaceutical interest. Molybdoenzymes contain a molybdenum cofactor (Moco), which is a pyranopterin heterocyclic compound that binds a molybdenum atom via a dithiolene group. Because Moco is a large and complex compound deeply buried within the protein, molybdoenzymes are accompanied by private chaperone proteins responsible for the cofactor's insertion into the enzyme and the enzyme's maturation. An efficient recombinant expression and purification of both Moco-free and Moco-containing molybdoenzymes and their chaperones is of paramount importance for fundamental and applied research related to molybdoenzymes. In this work, we focused on a D1 protein annotated as a chaperone of steroid C25 dehydrogenase (S25DH) from Sterolibacterium denitrificans Chol-1S. The D1 protein is presumably involved in the maturation of S25DH engaged in oxygen-independent oxidation of sterols. As this chaperone is thought to be a crucial element that ensures the insertion of Moco into the enzyme and consequently, proper folding of S25DH optimization of the chaperon's expression is the first step toward the development of recombinant expression and purification methods for S25DH. We have identified common E. coli strains and conditions for both expression and purification that allow us to selectively produce Moco-containing and Moco-free chaperones. We have also characterized the Moco-containing chaperone by EXAFS and HPLC analysis and identified conditions that stabilize both forms of the protein. The protocols presented here are efficient and result in protein quantities sufficient for biochemical studies.
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Affiliation(s)
- Ewa Niedzialkowska
- Jerzy Haber Institute of Catalysis and Surface Chemistry, Polish Academy of Sciences, Niezapominajek 8, 30239 Krakow, Poland.
| | - Beata Mrugała
- Jerzy Haber Institute of Catalysis and Surface Chemistry, Polish Academy of Sciences, Niezapominajek 8, 30239 Krakow, Poland
| | - Agnieszka Rugor
- Jerzy Haber Institute of Catalysis and Surface Chemistry, Polish Academy of Sciences, Niezapominajek 8, 30239 Krakow, Poland
| | - Mateusz P Czub
- Faculty of Chemistry, Jagiellonian University, Ingardena 3, Krakow 30060, Poland; Department of Molecular Physiology and Biological Physics, University of Virginia, 1340 Jefferson Park Avenue, Charlottesville, VA 22908, USA
| | - Anna Skotnicka
- Faculty of Agriculture and Economics, University of Agriculture in Krakow, Mickiewicza 21, 31120 Krakow, Poland
| | - Julien J H Cotelesage
- Molecular and Environmental Sciences Group, Department of Geological Sciences, University of Saskatchewan, Saskatoon, SK S7N 5E2, Canada
| | - Graham N George
- Molecular and Environmental Sciences Group, Department of Geological Sciences, University of Saskatchewan, Saskatoon, SK S7N 5E2, Canada
| | - Maciej Szaleniec
- Jerzy Haber Institute of Catalysis and Surface Chemistry, Polish Academy of Sciences, Niezapominajek 8, 30239 Krakow, Poland
| | - Wladek Minor
- Department of Molecular Physiology and Biological Physics, University of Virginia, 1340 Jefferson Park Avenue, Charlottesville, VA 22908, USA
| | - Krzysztof Lewiński
- Faculty of Chemistry, Jagiellonian University, Ingardena 3, Krakow 30060, Poland
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18
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Heider J, Szaleniec M, Sünwoldt K, Boll M. Ethylbenzene Dehydrogenase and Related Molybdenum Enzymes Involved in Oxygen-Independent Alkyl Chain Hydroxylation. J Mol Microbiol Biotechnol 2016; 26:45-62. [PMID: 26960184 DOI: 10.1159/000441357] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Ethylbenzene dehydrogenase initiates the anaerobic bacterial degradation of ethylbenzene and propylbenzene. Although the enzyme is currently only known from a few closely related denitrifying bacterial strains affiliated to the Rhodocyclaceae, it clearly marks a universally occurring mechanism used for attacking recalcitrant substrates in the absence of oxygen. Ethylbenzene dehydrogenase belongs to subfamily 2 of the DMSO reductase-type molybdenum enzymes together with paralogous enzymes involved in the oxygen-independent hydroxylation of p-cymene, the isoprenoid side chains of sterols and even possibly n-alkanes; the subfamily also extends to dimethylsulfide dehydrogenases, selenite, chlorate and perchlorate reductases and, most significantly, dissimilatory nitrate reductases. The biochemical, spectroscopic and structural properties of the oxygen-independent hydroxylases among these enzymes are summarized and compared. All of them consist of three subunits, contain a molybdenum-bis-molybdopterin guanine dinucleotide cofactor, five Fe-S clusters and a heme b cofactor of unusual ligation, and are localized in the periplasmic space as soluble enzymes. In the case of ethylbenzene dehydrogenase, it has been determined that the heme b cofactor has a rather high redox potential, which may also be inferred for the paralogous hydroxylases. The known structure of ethylbenzene dehydrogenase allowed the calculation of detailed models of the reaction mechanism based on the density function theory as well as QM-MM (quantum mechanics - molecular mechanics) methods, which yield predictions of mechanistic properties such as kinetic isotope effects that appeared consistent with experimental data.
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Affiliation(s)
- Johann Heider
- Laboratory of Microbial Biochemistry, LOEWE Center for Synthetic Microbiology, Philipps University of Marburg, Marburg, Germany
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