1
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Chen L, Wang X, Zou Y, Tang MC. Genome Mining of a Fungal Polyketide Synthase-Nonribosomal Peptide Synthetase Hybrid Megasynthetase Pathway to Synthesize a Phytotoxic N-Acyl Amino Acid. Org Lett 2024; 26:3597-3601. [PMID: 38661293 DOI: 10.1021/acs.orglett.4c01039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/26/2024]
Abstract
Guided by the retrobiosynthesis hypothesis, we characterized a fungal polyketide synthase-nonribosomal peptide synthetase (PKS-NRPS) hybrid megasynthetase pathway to generate 2-trans-4-trans-2-methylsorbyl-d-leucine (1), a polyketide amino acid conjugate that inhibits Arabidopsis root growth. The biosynthesis of 1 includes a PKS-NRPS enzyme to assemble an N-acyl amino alcohol intermediate, which is further oxidized to an N-acyl amino acid (NAAA), demonstrating a new biosynthetic logic for synthesizing NAAAs and expanding the chemical space of products encoded by fungal PKS-NRPS clusters.
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Affiliation(s)
- Lin Chen
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory on Metabolic & Developmental Sciences, School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
- Zhang jiang Institute for Advanced Study, Shanghai Jiao Tong University, Shanghai 201203, China
| | - Xin Wang
- College of Pharmaceutical Sciences, Southwest University, Chongqing 400715, China
| | - Yi Zou
- College of Pharmaceutical Sciences, Southwest University, Chongqing 400715, China
| | - Man-Cheng Tang
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory on Metabolic & Developmental Sciences, School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
- Zhang jiang Institute for Advanced Study, Shanghai Jiao Tong University, Shanghai 201203, China
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2
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Love AC, Purdy TN, Hubert FM, Kirwan EJ, Holland DC, Moore BS. Discovery of Latent Cannabichromene Cyclase Activity in Marine Bacterial Flavoenzymes. ACS Synth Biol 2024; 13:1343-1354. [PMID: 38459634 PMCID: PMC11031283 DOI: 10.1021/acssynbio.4c00051] [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: 03/10/2024]
Abstract
Production of phytocannabinoids remains an area of active scientific interest due to the growing use of cannabis by the public and the underexplored therapeutic potential of the over 100 minor cannabinoids. While phytocannabinoids are biosynthesized by Cannabis sativa and other select plants and fungi, structural analogs and stereoisomers can only be accessed synthetically or through heterologous expression. To date, the bioproduction of cannabinoids has required eukaryotic hosts like yeast since key, native oxidative cyclization enzymes do not express well in bacterial hosts. Here, we report that two marine bacterial flavoenzymes, Clz9 and Tcz9, perform oxidative cyclization reactions on phytocannabinoid precursors to efficiently generate cannabichromene scaffolds. Furthermore, Clz9 and Tcz9 express robustly in bacteria and display significant tolerance to organic solvent and high substrate loading, thereby enabling fermentative production of cannabichromenic acid in Escherichia coli and indicating their potential for biocatalyst development.
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Affiliation(s)
- Anna C. Love
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California San Diego, La Jolla, California 92093, United States
| | - Trevor N. Purdy
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California San Diego, La Jolla, California 92093, United States
| | - Felix M. Hubert
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California San Diego, La Jolla, California 92093, United States
| | - Ella J. Kirwan
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California San Diego, La Jolla, California 92093, United States
| | - Darren C. Holland
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California San Diego, La Jolla, California 92093, United States
| | - Bradley S. Moore
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California San Diego, La Jolla, California 92093, United States
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, California 92093, United States
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3
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Zhang X, Pang X, Zhang L, Li Y, Song Y, Xiao H, Liu Y, Wang J, Yan Y. Genome Mining Uncovers a Flavoenzyme-Catalyzed Isomerization Process during the Maturation of Pyrenophorol Dilactones. Org Lett 2024; 26:1612-1617. [PMID: 38377309 DOI: 10.1021/acs.orglett.4c00008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2024]
Abstract
The biosynthetic gene cluster responsible for the production of C2-asymmetric 16-membered dilactones, including pyrenophorol and its derivatives, was discovered through genome mining of polyketides from a sponge-derived fungus. The biosynthetic pathway of the pyrenophorol dilactones was subsequently elucidated. A distinctive flavoenzyme PylE was identified to catalyze the isomerization of the 4-alcohol-2,3-unsaturated moiety within the dilactone scaffold, resulting in the formation of a 1,4-diketone. Further insights into the catalytic mechanism of PylE were obtained through mutagenesis experiments combined with molecular docking.
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Affiliation(s)
- Xiufeng Zhang
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, South China Sea Institute of Oceanology, Chinese Academy of Sciences, 164 West Xingang Road, Guangzhou 510301, China
- University of Chinese Academy of Science, 19 Yuquan Road, Beijing 100049, China
- Sanya Institute of Oceanology Eco-Environmental Engineering, Yazhou Scientific Bay, Sanya 572000, China
| | - Xiaoyan Pang
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, South China Sea Institute of Oceanology, Chinese Academy of Sciences, 164 West Xingang Road, Guangzhou 510301, China
- University of Chinese Academy of Science, 19 Yuquan Road, Beijing 100049, China
| | - Liping Zhang
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, South China Sea Institute of Oceanology, Chinese Academy of Sciences, 164 West Xingang Road, Guangzhou 510301, China
- University of Chinese Academy of Science, 19 Yuquan Road, Beijing 100049, China
| | - Yanqin Li
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, South China Sea Institute of Oceanology, Chinese Academy of Sciences, 164 West Xingang Road, Guangzhou 510301, China
- University of Chinese Academy of Science, 19 Yuquan Road, Beijing 100049, China
- Sanya Institute of Oceanology Eco-Environmental Engineering, Yazhou Scientific Bay, Sanya 572000, China
| | - Yongxiang Song
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, South China Sea Institute of Oceanology, Chinese Academy of Sciences, 164 West Xingang Road, Guangzhou 510301, China
- University of Chinese Academy of Science, 19 Yuquan Road, Beijing 100049, China
- Sanya Institute of Oceanology Eco-Environmental Engineering, Yazhou Scientific Bay, Sanya 572000, China
| | - Hua Xiao
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, South China Sea Institute of Oceanology, Chinese Academy of Sciences, 164 West Xingang Road, Guangzhou 510301, China
- University of Chinese Academy of Science, 19 Yuquan Road, Beijing 100049, China
- Sanya Institute of Oceanology Eco-Environmental Engineering, Yazhou Scientific Bay, Sanya 572000, China
| | - Yonghong Liu
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, South China Sea Institute of Oceanology, Chinese Academy of Sciences, 164 West Xingang Road, Guangzhou 510301, China
- University of Chinese Academy of Science, 19 Yuquan Road, Beijing 100049, China
| | - Junfeng Wang
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, South China Sea Institute of Oceanology, Chinese Academy of Sciences, 164 West Xingang Road, Guangzhou 510301, China
- University of Chinese Academy of Science, 19 Yuquan Road, Beijing 100049, China
- Sanya Institute of Oceanology Eco-Environmental Engineering, Yazhou Scientific Bay, Sanya 572000, China
| | - Yan Yan
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, South China Sea Institute of Oceanology, Chinese Academy of Sciences, 164 West Xingang Road, Guangzhou 510301, China
- University of Chinese Academy of Science, 19 Yuquan Road, Beijing 100049, China
- Sanya Institute of Oceanology Eco-Environmental Engineering, Yazhou Scientific Bay, Sanya 572000, China
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4
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Yu L, Wang X, Tang C, Wang H, Rabbani Nasab H, Kang Z, Wang J. Genome-Wide Characterization of Berberine Bridge Enzyme Gene Family in Wheat ( Triticum aestivum L.) and the Positive Regulatory Role of TaBBE64 in Response to Wheat Stripe Rust. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2023; 71:19986-19999. [PMID: 38063491 DOI: 10.1021/acs.jafc.3c06280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2023]
Abstract
Berberine bridge enzymes (BBEs), functioning as carbonate oxidases, enhance disease resistance in Arabidopsis and tobacco. However, the understanding of BBEs' role in monocots against pathogens remains limited. This study identified 81 TaBBEs with FAD_binding_4 and BBE domains. Phylogenetic analysis revealed a separation of the BBE gene family between monocots and dicots. Notably, RNA-seq showed TaBBE64's significant induction by both pathogen-associated molecular pattern treatment and Puccinia striiformis f. sp. tritici (Pst) infection at early stages. Subcellular localization revealed TaBBE64 at the cytoplasmic membrane. Knocking down TaBBE64 compromised wheat's Pst resistance, reducing reactive oxygen species and promoting fungal growth, confirming its positive role. Molecular docking and enzyme activity assays confirmed TaBBE64's glucose oxidation to produce H2O2. Since Pst relies on living wheat cells for carbohydrate absorption, TaBBE64's promotion of glucose oxidation limits fungal growth and resists pathogen infection. This study sheds light on BBEs' role in wheat resistance against biotrophic fungi.
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Affiliation(s)
- Ligang Yu
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Plant Protection, Northwest A & F University, Yangling 712100, P. R. China
| | - Xiaojie Wang
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Plant Protection, Northwest A & F University, Yangling 712100, P. R. China
| | - Chunlei Tang
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Plant Protection, Northwest A & F University, Yangling 712100, P. R. China
| | - Huiqing Wang
- Plant Protection Station of Xinjiang Uygur Autonomous Region, Urumqi 830006, Xinjiang, P. R. China
| | - Hojjatollah Rabbani Nasab
- Plant Protection Research Department, Agricultural and Natural Resources Research and Education Centre of Golestan Province, Agricultural Research Education and Extension Organization (AREEO), Gorgan 999067, Iran
| | - Zhensheng Kang
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Plant Protection, Northwest A & F University, Yangling 712100, P. R. China
| | - Jianfeng Wang
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Plant Protection, Northwest A & F University, Yangling 712100, P. R. China
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5
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Xu Z, Tian P. Rethinking Biosynthesis of Aclacinomycin A. Molecules 2023; 28:molecules28062761. [PMID: 36985733 PMCID: PMC10054333 DOI: 10.3390/molecules28062761] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2023] [Revised: 03/01/2023] [Accepted: 03/06/2023] [Indexed: 03/22/2023] Open
Abstract
Aclacinomycin A (ACM-A) is an anthracycline antitumor agent widely used in clinical practice. The current industrial production of ACM-A relies primarily on chemical synthesis and microbial fermentation. However, chemical synthesis involves multiple reactions which give rise to high production costs and environmental pollution. Microbial fermentation is a sustainable strategy, yet the current fermentation yield is too low to satisfy market demand. Hence, strain improvement is highly desirable, and tremendous endeavors have been made to decipher biosynthesis pathways and modify key enzymes. In this review, we comprehensively describe the reported biosynthesis pathways, key enzymes, and, especially, catalytic mechanisms. In addition, we come up with strategies to uncover unknown enzymes and improve the activities of rate-limiting enzymes. Overall, this review aims to provide valuable insights for complete biosynthesis of ACM-A.
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6
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Xiang P, Kemmerich B, Yang L, Li SM. Biosynthesis of Annullatin D in Penicillium roqueforti Implies Oxidative Lactonization between Two Hydroxyl Groups Catalyzed by a BBE-like Enzyme. Org Lett 2022; 24:6072-6077. [PMID: 35939524 DOI: 10.1021/acs.orglett.2c02438] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Annullatins from Cordyceps annullata are alkylated aromatic polyketides including annullatin D with a fused dihydrobenzofuran lactone ring system. Here, we report the identification of a silent biosynthetic gene cluster for annullatins from Penicillium roqueforti by heterologous expression in Aspergillus nidulans, gene deletion, and feeding experiments as well as by biochemical characterization. The polyketide core structure is consecutively modified by hydroxylation and prenylation. A berberine bridge enzyme-like protein catalyzes the final step, an oxidative lactonization between two hydroxyl groups, to form (2S, 9S)-annullatin D.
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Affiliation(s)
- Pan Xiang
- Institut für Pharmazeutische Biologie und Biotechnologie, Fachbereich Pharmazie, Philipps-Universität Marburg, Robert-Koch-Straße 4, 35037 Marburg, Germany
| | - Bastian Kemmerich
- Institut für Pharmazeutische Biologie und Biotechnologie, Fachbereich Pharmazie, Philipps-Universität Marburg, Robert-Koch-Straße 4, 35037 Marburg, Germany
| | - Li Yang
- Haikou Key Laboratory for Research and Utilization of Tropical Natural Products, Institute of Tropical Bioscience and Biotechnology, CATAS, 571101 Haikou, China
| | - Shu-Ming Li
- Institut für Pharmazeutische Biologie und Biotechnologie, Fachbereich Pharmazie, Philipps-Universität Marburg, Robert-Koch-Straße 4, 35037 Marburg, Germany
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7
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Purdy TN, Moore BS, Lukowski AL. Harnessing ortho-Quinone Methides in Natural Product Biosynthesis and Biocatalysis. JOURNAL OF NATURAL PRODUCTS 2022; 85:688-701. [PMID: 35108487 PMCID: PMC9006567 DOI: 10.1021/acs.jnatprod.1c01026] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The implementation of ortho-quinone methide (o-QM) intermediates in complex molecule assembly represents a remarkably efficient strategy designed by Nature and utilized by synthetic chemists. o-QMs have been taken advantage of in biomimetic syntheses for decades, yet relatively few examples of o-QM-generating enzymes in natural product biosynthetic pathways have been reported. The biosynthetic enzymes that have been discovered thus far exhibit tremendous potential for biocatalytic applications, enabling the selective production of desirable compounds that are otherwise intractable or inherently difficult to achieve by traditional synthetic methods. Characterization of this biosynthetic machinery has the potential to shine a light on new enzymes capable of similar chemistry on diverse substrates, thus expanding our knowledge of Nature's catalytic repertoire. The presently known o-QM-generating enzymes include flavin-dependent oxidases, hetero-Diels-Alderases, S-adenosyl-l-methionine-dependent pericyclases, and α-ketoglutarate-dependent nonheme iron enzymes. In this review, we discuss their diverse enzymatic mechanisms and potential as biocatalysts in constructing natural product molecules such as cannabinoids.
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Affiliation(s)
- Trevor N Purdy
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, La Jolla, California 92093, United States
| | - Bradley S Moore
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, La Jolla, California 92093, United States
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California at San Diego, La Jolla, California 92093, United States
| | - April L Lukowski
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, La Jolla, California 92093, United States
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8
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Zhang JM, Liu X, Wei Q, Ma C, Li D, Zou Y. Berberine bridge enzyme-like oxidase-catalysed double bond isomerization acts as the pathway switch in cytochalasin synthesis. Nat Commun 2022; 13:225. [PMID: 35017571 PMCID: PMC8752850 DOI: 10.1038/s41467-021-27931-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Accepted: 12/10/2021] [Indexed: 11/09/2022] Open
Abstract
Cytochalasans (CYTs), as well as their polycyclic (pcCYTs) and polymerized (meCYTs) derivatives, constitute one of the largest families of fungal polyketide-nonribosomal peptide (PK-NRP) hybrid natural products. However, the mechanism of chemical conversion from mono-CYTs (moCYTs) to both pcCYTs and meCYTs remains unknown. Here, we show the first successful example of the reconstitution of the CYT core backbone as well as the whole pathway in a heterologous host. Importantly, we also describe the berberine bridge enzyme (BBE)-like oxidase AspoA, which uses Glu538 as a general acid biocatalyst to catalyse an unusual protonation-driven double bond isomerization reaction and acts as a switch to alter the native (for moCYTs) and nonenzymatic (for pcCYTs and meCYTs) pathways to synthesize aspochalasin family compounds. Our results present an unprecedented function of BBE-like enzymes and highly suggest that the isolated pcCYTs and meCYTs are most likely artificially derived products.
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Affiliation(s)
- Jin-Mei Zhang
- College of Pharmaceutical Sciences, Southwest University, Chongqing, 400715, China
| | - Xuan Liu
- College of Pharmaceutical Sciences, Southwest University, Chongqing, 400715, China
| | - Qian Wei
- College of Pharmaceutical Sciences, Southwest University, Chongqing, 400715, China
| | - Chuanteng Ma
- Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao, 266003, China
| | - Dehai Li
- Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao, 266003, China
| | - Yi Zou
- College of Pharmaceutical Sciences, Southwest University, Chongqing, 400715, China.
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9
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Eggers R, Jammer A, Jha S, Kerschbaumer B, Lahham M, Strandback E, Toplak M, Wallner S, Winkler A, Macheroux P. The scope of flavin-dependent reactions and processes in the model plant Arabidopsis thaliana. PHYTOCHEMISTRY 2021; 189:112822. [PMID: 34118767 DOI: 10.1016/j.phytochem.2021.112822] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Revised: 05/23/2021] [Accepted: 05/24/2021] [Indexed: 06/12/2023]
Abstract
Flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD) are utilized as coenzymes in many biochemical reduction-oxidation reactions owing to the ability of the tricyclic isoalloxazine ring system to employ the oxidized, radical and reduced state. We have analyzed the genome of Arabidopsis thaliana to establish an inventory of genes encoding flavin-dependent enzymes (flavoenzymes) as a basis to explore the range of flavin-dependent biochemical reactions that occur in this model plant. Expectedly, flavoenzymes catalyze many pivotal reactions in primary catabolism, which are connected to the degradation of basic metabolites, such as fatty and amino acids as well as carbohydrates and purines. On the other hand, flavoenzymes play diverse roles in anabolic reactions most notably the biosynthesis of amino acids as well as the biosynthesis of pyrimidines and sterols. Importantly, the role of flavoenzymes goes much beyond these basic reactions and extends into pathways that are equally crucial for plant life, for example the production of natural products. In this context, we outline the participation of flavoenzymes in the biosynthesis and maintenance of cofactors, coenzymes and accessory plant pigments (e. g. carotenoids) as well as phytohormones. Moreover, several multigene families have emerged as important components of plant immunity, for example the family of berberine bridge enzyme-like enzymes, flavin-dependent monooxygenases and NADPH oxidases. Furthermore, the versatility of flavoenzymes is highlighted by their role in reactions leading to tRNA-modifications, chromatin regulation and cellular redox homeostasis. The favorable photochemical properties of the flavin chromophore are exploited by photoreceptors to govern crucial processes of plant adaptation and development. Finally, a sequence- and structure-based approach was undertaken to gain insight into the catalytic role of uncharacterized flavoenzymes indicating their involvement in unknown biochemical reactions and pathways in A. thaliana.
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Affiliation(s)
- Reinmar Eggers
- Institute of Biochemistry, Graz University of Technology, Petersgasse 12/2, 8010, Graz, Austria
| | - Alexandra Jammer
- Institute of Biochemistry, Graz University of Technology, Petersgasse 12/2, 8010, Graz, Austria
| | - Shalinee Jha
- Institute of Biochemistry, Graz University of Technology, Petersgasse 12/2, 8010, Graz, Austria
| | - Bianca Kerschbaumer
- Institute of Biochemistry, Graz University of Technology, Petersgasse 12/2, 8010, Graz, Austria
| | - Majd Lahham
- Institute of Biochemistry, Graz University of Technology, Petersgasse 12/2, 8010, Graz, Austria
| | - Emilia Strandback
- Institute of Biochemistry, Graz University of Technology, Petersgasse 12/2, 8010, Graz, Austria
| | - Marina Toplak
- Institute of Biochemistry, Graz University of Technology, Petersgasse 12/2, 8010, Graz, Austria
| | - Silvia Wallner
- Institute of Biochemistry, Graz University of Technology, Petersgasse 12/2, 8010, Graz, Austria
| | - Andreas Winkler
- Institute of Biochemistry, Graz University of Technology, Petersgasse 12/2, 8010, Graz, Austria
| | - Peter Macheroux
- Institute of Biochemistry, Graz University of Technology, Petersgasse 12/2, 8010, Graz, Austria.
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10
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Discovery of fungal oligosaccharide-oxidising flavo-enzymes with previously unknown substrates, redox-activity profiles and interplay with LPMOs. Nat Commun 2021; 12:2132. [PMID: 33837197 PMCID: PMC8035211 DOI: 10.1038/s41467-021-22372-0] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Accepted: 03/09/2021] [Indexed: 12/14/2022] Open
Abstract
Oxidative plant cell-wall processing enzymes are of great importance in biology and biotechnology. Yet, our insight into the functional interplay amongst such oxidative enzymes remains limited. Here, a phylogenetic analysis of the auxiliary activity 7 family (AA7), currently harbouring oligosaccharide flavo-oxidases, reveals a striking abundance of AA7-genes in phytopathogenic fungi and Oomycetes. Expression of five fungal enzymes, including three from unexplored clades, expands the AA7-substrate range and unveils a cellooligosaccharide dehydrogenase activity, previously unknown within AA7. Sequence and structural analyses identify unique signatures distinguishing the strict dehydrogenase clade from canonical AA7 oxidases. The discovered dehydrogenase directly is able to transfer electrons to an AA9 lytic polysaccharide monooxygenase (LPMO) and fuel cellulose degradation by LPMOs without exogenous reductants. The expansion of redox-profiles and substrate range highlights the functional diversity within AA7 and sets the stage for harnessing AA7 dehydrogenases to fine-tune LPMO activity in biotechnological conversion of plant feedstocks. Microbial oxidoreductases are key in biomass breakdown. Here, the authors expand the specificity and redox scope within fungal auxiliary activity 7 family (AA7) enzymes and show that AA7 oligosaccharide dehydrogenases can directly fuel cellulose degradation by lytic polysaccharide monooxygenases.
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11
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Abstract
This review presents a historical outline of the research on vanillyl alcohol oxidase (VAO) from Penicillium simplicissimum, one of the canonical members of the VAO/PCMH flavoprotein family. After describing its discovery and initial biochemical characterization, we discuss the physiological role, substrate scope, and catalytic mechanism of VAO, and review its three-dimensional structure and mechanism of covalent flavinylation. We also explain how protein engineering provided a deeper insight into the role of certain amino acid residues in determining the substrate specificity and enantioselectivity of the enzyme. Finally, we summarize recent computational studies about the migration of substrates and products through the enzyme's structure and the phylogenetic distribution of VAO and related enzymes.
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Affiliation(s)
- Tom A Ewing
- Wageningen Food & Biobased Research, Wageningen University & Research, Wageningen, The Netherlands
| | - Gudrun Gygli
- Institute for Biological Interfaces, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Marco W Fraaije
- Molecular Enzymology Group, University of Groningen, Groningen, The Netherlands
| | - Willem J H van Berkel
- Laboratory of Food Chemistry, Wageningen University & Research, Wageningen, The Netherlands.
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12
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Miller AF, Duan HD, Varner TA, Mohamed Raseek N. Reduction midpoint potentials of bifurcating electron transfer flavoproteins. Methods Enzymol 2019; 620:365-398. [PMID: 31072494 DOI: 10.1016/bs.mie.2019.03.017] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Recently, a variety of enzymes have been found to accept electrons from NAD(P)H yet reduce lower-potential carriers such as ferredoxin and flavodoxin semiquinone, in apparent violation of thermodynamics. The reaction is favorable overall, however, because these enzymes couple the foregoing endergonic one-electron transfer to exergonic transfer of the other electron from each NAD(P)H, in a process called "flavin-based electron bifurcation." The reduction midpoint potentials (E°s) of the multiple flavins in these enzymes are critical to their mechanisms. We describe methods we have found to be useful for measuring each of the E°s of each of the flavins in bifurcating electron transfer flavoproteins.
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Affiliation(s)
- A-F Miller
- Department of Chemistry, University of Kentucky, Lexington, KY, United States.
| | - H D Duan
- Department of Chemistry, University of Kentucky, Lexington, KY, United States
| | - T A Varner
- Department of Chemistry, University of Kentucky, Lexington, KY, United States
| | - N Mohamed Raseek
- Department of Chemistry, University of Kentucky, Lexington, KY, United States
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13
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The family of berberine bridge enzyme-like enzymes: A treasure-trove of oxidative reactions. Arch Biochem Biophys 2017; 632:88-103. [PMID: 28676375 DOI: 10.1016/j.abb.2017.06.023] [Citation(s) in RCA: 81] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Revised: 06/29/2017] [Accepted: 06/30/2017] [Indexed: 12/18/2022]
Abstract
Biological oxidations form the basis of life on earth by utilizing organic compounds as electron donors to drive the generation of metabolic energy carriers, such as ATP. Oxidative reactions are also important for the biosynthesis of complex compounds, i.e. natural products such as alkaloids that provide vital benefits for organisms in all kingdoms of life. The vitamin B2-derived cofactors flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD) enable an astonishingly diverse array of oxidative reactions that is based on the versatility of the redox-active isoalloxazine ring. The family of FAD-linked oxidases can be divided into subgroups depending on specific sequence features in an otherwise very similar structural context. The sub-family of berberine bridge enzyme (BBE)-like enzymes has recently attracted a lot of attention due to the challenging chemistry catalyzed by its members and the unique and unusual bi-covalent attachment of the FAD cofactor. This family is the focus of the present review highlighting recent advancements into the structural and functional aspects of members from bacteria, fungi and plants. In view of the unprecedented reaction catalyzed by the family's namesake, BBE from the California poppy, recent studies have provided further insights into nature's treasure chest of oxidative reactions.
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Abstract
Oxidative cyclizations are important transformations that occur widely during natural product biosynthesis. The transformations from acyclic precursors to cyclized products can afford morphed scaffolds, structural rigidity, and biological activities. Some of the most dramatic structural alterations in natural product biosynthesis occur through oxidative cyclization. In this Review, we examine the different strategies used by nature to create new intra(inter)molecular bonds via redox chemistry. This Review will cover both oxidation- and reduction-enabled cyclization mechanisms, with an emphasis on the former. Radical cyclizations catalyzed by P450, nonheme iron, α-KG-dependent oxygenases, and radical SAM enzymes are discussed to illustrate the use of molecular oxygen and S-adenosylmethionine to forge new bonds at unactivated sites via one-electron manifolds. Nonradical cyclizations catalyzed by flavin-dependent monooxygenases and NAD(P)H-dependent reductases are covered to show the use of two-electron manifolds in initiating cyclization reactions. The oxidative installations of epoxides and halogens into acyclic scaffolds to drive subsequent cyclizations are separately discussed as examples of "disappearing" reactive handles. Last, oxidative rearrangement of rings systems, including contractions and expansions, will be covered.
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Affiliation(s)
- Man-Cheng Tang
- Department of Chemical and Biomolecular Engineering, Department of Chemistry and Biochemistry, University of California, Los Angeles, 420 Westwood Plaza, Los Angeles, CA 90095, USA
| | - Yi Zou
- Department of Chemical and Biomolecular Engineering, Department of Chemistry and Biochemistry, University of California, Los Angeles, 420 Westwood Plaza, Los Angeles, CA 90095, USA
| | - Kenji Watanabe
- Department of Pharmaceutical Sciences, University of Shizuoka, Shizuoka 422-8526, Japan
| | - Christopher T. Walsh
- Stanford University Chemistry, Engineering, and Medicine for Human Health (ChEM-H), Stanford University, 443 Via Ortega, Stanford, CA 94305
| | - Yi Tang
- Department of Chemical and Biomolecular Engineering, Department of Chemistry and Biochemistry, University of California, Los Angeles, 420 Westwood Plaza, Los Angeles, CA 90095, USA
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Liu C, Minami A, Dairi T, Gomi K, Scott B, Oikawa H. Biosynthesis of Shearinine: Diversification of a Tandem Prenyl Moiety of Fungal Indole Diterpenes. Org Lett 2016; 18:5026-5029. [PMID: 27632559 DOI: 10.1021/acs.orglett.6b02482] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The late-stage biosynthetic pathway of the indole diterpene shearinine involving four enzymatic reactions (JanQDOJ) was elucidated by an efficient heterologous expression system using Aspergillus oryzae. Key oxidative cyclization, forming a characteristic A/B bicyclic shearinine core by flavoprotein oxidase, was studied using a substrate analogue and a buffer containing H218O. These experimental data provided evidence that JanO catalyzes two-step oxidation via a hydroxylated product and that the JanO reaction involves the hydride-transfer mechanism.
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Affiliation(s)
- Chengwei Liu
- Division of Chemistry, Graduate School of Science, Hokkaido University , Sapporo 060-0810, Japan
| | - Atsushi Minami
- Division of Chemistry, Graduate School of Science, Hokkaido University , Sapporo 060-0810, Japan
| | - Tohru Dairi
- Graduate School of Engineering, Hokkaido University , Sapporo 060-8628, Japan
| | - Katsuya Gomi
- Graduate School of Agricultural Science, Tohoku University , Sendai 981-8555, Japan
| | - Barry Scott
- Institute of Fundamental Sciences, Massey University , Palmerston North 4442, New Zealand
| | - Hideaki Oikawa
- Division of Chemistry, Graduate School of Science, Hokkaido University , Sapporo 060-0810, Japan
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Hemmerling F, Hahn F. Biosynthesis of oxygen and nitrogen-containing heterocycles in polyketides. Beilstein J Org Chem 2016; 12:1512-50. [PMID: 27559404 PMCID: PMC4979870 DOI: 10.3762/bjoc.12.148] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Accepted: 06/22/2016] [Indexed: 01/01/2023] Open
Abstract
This review highlights the biosynthesis of heterocycles in polyketide natural products with a focus on oxygen and nitrogen-containing heterocycles with ring sizes between 3 and 6 atoms. Heterocycles are abundant structural elements of natural products from all classes and they often contribute significantly to their biological activity. Progress in recent years has led to a much better understanding of their biosynthesis. In this context, plenty of novel enzymology has been discovered, suggesting that these pathways are an attractive target for future studies.
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Affiliation(s)
- Franziska Hemmerling
- Institut für Organische Chemie and Zentrum für Biomolekulare Wirkstoffe, Gottfried Wilhelm Leibniz Universität Hannover, Schneiderberg 38, 30167 Hannover, Germany; Fakultät für Biologie, Chemie und Geowissenschaften, Universität Bayreuth, Universitätsstraße 30, 95440 Bayreuth, Germany
| | - Frank Hahn
- Institut für Organische Chemie and Zentrum für Biomolekulare Wirkstoffe, Gottfried Wilhelm Leibniz Universität Hannover, Schneiderberg 38, 30167 Hannover, Germany; Fakultät für Biologie, Chemie und Geowissenschaften, Universität Bayreuth, Universitätsstraße 30, 95440 Bayreuth, Germany
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Kayhan J, Wanner MJ, Ingemann S, van Maarseveen JH, Hiemstra H. Consecutive Pictet-Spengler Condensations toward Bioactive 8-Benzylprotoberberines: Highly Selective Total Syntheses of (+)-Javaberine A, (+)-Javaberine B, and (-)-Latifolian A. European J Org Chem 2016. [DOI: 10.1002/ejoc.201600764] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Affiliation(s)
- Jenifer Kayhan
- Van't Hoff Institute for Molecular Sciences; University of Amsterdam; Science Park 904 1098 XH Amsterdam The Netherlands
| | - Martin J. Wanner
- Van't Hoff Institute for Molecular Sciences; University of Amsterdam; Science Park 904 1098 XH Amsterdam The Netherlands
| | - Steen Ingemann
- Van't Hoff Institute for Molecular Sciences; University of Amsterdam; Science Park 904 1098 XH Amsterdam The Netherlands
| | - Jan H. van Maarseveen
- Van't Hoff Institute for Molecular Sciences; University of Amsterdam; Science Park 904 1098 XH Amsterdam The Netherlands
| | - Henk Hiemstra
- Van't Hoff Institute for Molecular Sciences; University of Amsterdam; Science Park 904 1098 XH Amsterdam The Netherlands
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Structure of a Berberine Bridge Enzyme-Like Enzyme with an Active Site Specific to the Plant Family Brassicaceae. PLoS One 2016; 11:e0156892. [PMID: 27276217 PMCID: PMC4898691 DOI: 10.1371/journal.pone.0156892] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Accepted: 05/21/2016] [Indexed: 01/15/2023] Open
Abstract
Berberine bridge enzyme-like (BBE-like) proteins form a multigene family (pfam 08031), which is present in plants, fungi and bacteria. They adopt the vanillyl alcohol-oxidase fold and predominantly show bi-covalent tethering of the FAD cofactor to a cysteine and histidine residue, respectively. The Arabidopsis thaliana genome was recently shown to contain genes coding for 28 BBE-like proteins, while featuring four distinct active site compositions. We determined the structure of a member of the AtBBE-like protein family (termed AtBBE-like 28), which has an active site composition that has not been structurally and biochemically characterized thus far. The most salient and distinguishing features of the active site found in AtBBE-like 28 are a mono-covalent linkage of a histidine to the 8α-position of the flavin-isoalloxazine ring and the lack of a second covalent linkage to the 6-position, owing to the replacement of a cysteine with a histidine. In addition, the structure reveals the interaction of a glutamic acid (Glu426) with an aspartic acid (Asp369) at the active site, which appear to share a proton. This arrangement leads to the delocalization of a negative charge at the active site that may be exploited for catalysis. The structure also indicates a shift of the position of the isoalloxazine ring in comparison to other members of the BBE-like family. The dioxygen surrogate chloride was found near the C(4a) position of the isoalloxazine ring in the oxygen pocket, pointing to a rapid reoxidation of reduced enzyme by dioxygen. A T-DNA insertional mutant line for AtBBE-like 28 results in a phenotype, that is characterized by reduced biomass and lower salt stress tolerance. Multiple sequence analysis showed that the active site composition found in AtBBE-like 28 is only present in the Brassicaceae, suggesting that it plays a specific role in the metabolism of this plant family.
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Gandomkar S, Fischereder EM, Schrittwieser JH, Wallner S, Habibi Z, Macheroux P, Kroutil W. Enantioselective Oxidative Aerobic Dealkylation of N-Ethyl Benzylisoquinolines by Employing the Berberine Bridge Enzyme. Angew Chem Int Ed Engl 2015; 54:15051-4. [PMID: 26487450 DOI: 10.1002/anie.201507970] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Indexed: 12/24/2022]
Abstract
N-Dealkylation methods are well described for organic chemistry and the reaction is known in nature and drug metabolism; however, to our knowledge, enantioselective N-dealkylation has not been yet reported. In this study, exclusively the (S)-enantiomers of racemic N-ethyl tertiary amines (1-benzyl-N-ethyl-1,2,3,4-tetrahydroisoquinolines) were dealkylated to give the corresponding secondary (S)-amines in an enantioselective fashion at the expense of molecular oxygen. The reaction is catalyzed by the berberine bridge enzyme, which is known for CC bond formation. The dealkylation was demonstrated on a 100 mg scale and gave optically pure dealkylated products (ee>99 %).
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Affiliation(s)
- Somayyeh Gandomkar
- Institut für Chemie, Organische & Bioorganische Chemie, Universität Graz, NAWI Graz, Heinrichstraße 28, 8010 Graz (Austria).,Department of Pure Chemistry, Faculty of Chemistry, Shahid Beheshti University, G.C. District 1, Evin, Daneshjou Blvd, Tehran (Iran)
| | - Eva-Maria Fischereder
- Institut für Chemie, Organische & Bioorganische Chemie, Universität Graz, NAWI Graz, Heinrichstraße 28, 8010 Graz (Austria)
| | - Joerg H Schrittwieser
- Institut für Chemie, Organische & Bioorganische Chemie, Universität Graz, NAWI Graz, Heinrichstraße 28, 8010 Graz (Austria)
| | - Silvia Wallner
- Institut für Biochemie, Technische Universität Graz, Petersgasse 12, 8010 Graz (Austria)
| | - Zohreh Habibi
- Department of Pure Chemistry, Faculty of Chemistry, Shahid Beheshti University, G.C. District 1, Evin, Daneshjou Blvd, Tehran (Iran)
| | - Peter Macheroux
- Institut für Biochemie, Technische Universität Graz, Petersgasse 12, 8010 Graz (Austria)
| | - Wolfgang Kroutil
- Institut für Chemie, Organische & Bioorganische Chemie, Universität Graz, NAWI Graz, Heinrichstraße 28, 8010 Graz (Austria)
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Gandomkar S, Fischereder EM, Schrittwieser JH, Wallner S, Habibi Z, Macheroux P, Kroutil W. Enantioselektive oxidative aerobe Desalkylierung vonN-Ethylbenzyl- isochinolinen mithilfe des Berberin-Brücken-Enzyms. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201507970] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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21
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Daniel B, Pavkov-Keller T, Steiner B, Dordic A, Gutmann A, Nidetzky B, Sensen CW, van der Graaff E, Wallner S, Gruber K, Macheroux P. Oxidation of Monolignols by Members of the Berberine Bridge Enzyme Family Suggests a Role in Plant Cell Wall Metabolism. J Biol Chem 2015; 290:18770-81. [PMID: 26037923 PMCID: PMC4513132 DOI: 10.1074/jbc.m115.659631] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2015] [Indexed: 12/27/2022] Open
Abstract
Plant genomes contain a large number of genes encoding for berberine bridge enzyme (BBE)-like enzymes. Despite the widespread occurrence and abundance of this protein family in the plant kingdom, the biochemical function remains largely unexplored. In this study, we have expressed two members of the BBE-like enzyme family from Arabidopsis thaliana in the host organism Komagataella pastoris. The two proteins, termed AtBBE-like 13 and AtBBE-like 15, were purified, and their catalytic properties were determined. In addition, AtBBE-like 15 was crystallized and structurally characterized by x-ray crystallography. Here, we show that the enzymes catalyze the oxidation of aromatic allylic alcohols, such as coumaryl, sinapyl, and coniferyl alcohol, to the corresponding aldehydes and that AtBBE-like 15 adopts the same fold as vanillyl alcohol oxidase as reported previously for berberine bridge enzyme and other FAD-dependent oxidoreductases. Further analysis of the substrate range identified coniferin, the glycosylated storage form of coniferyl alcohol, as a substrate of the enzymes, whereas other glycosylated monolignols were rather poor substrates. A detailed analysis of the motifs present in the active sites of the BBE-like enzymes in A. thaliana suggested that 14 out of 28 members of the family might catalyze similar reactions. Based on these findings, we propose a novel role of BBE-like enzymes in monolignol metabolism that was previously not recognized for this enzyme family.
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Affiliation(s)
| | - Tea Pavkov-Keller
- the Institute of Molecular Biosciences, University of Graz, 8010 Graz, Austria, the ACIB GmbH, 8010 Graz, Austria, and
| | | | - Andela Dordic
- the Institute of Molecular Biosciences, University of Graz, 8010 Graz, Austria, the ACIB GmbH, 8010 Graz, Austria, and
| | | | | | - Christoph W Sensen
- Molecular Biotechnology, Graz University of Technology, 8010 Graz, Austria
| | - Eric van der Graaff
- the Section for Crop Sciences, Copenhagen University, 2630 Copenhagen, Denmark
| | | | - Karl Gruber
- the Institute of Molecular Biosciences, University of Graz, 8010 Graz, Austria
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Zafred D, Steiner B, Teufelberger AR, Hromic A, Karplus PA, Schofield CJ, Wallner S, Macheroux P. Rationally engineered flavin-dependent oxidase reveals steric control of dioxygen reduction. FEBS J 2015; 282:3060-74. [PMID: 25619330 DOI: 10.1111/febs.13212] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Revised: 01/20/2015] [Accepted: 01/21/2015] [Indexed: 01/12/2023]
Abstract
UNLABELLED The ability of flavoenzymes to reduce dioxygen varies greatly, and is controlled by the protein environment, which may cause either a rapid reaction (oxidases) or a sluggish reaction (dehydrogenases). Previously, a 'gatekeeper' amino acid residue was identified that controls the reactivity to dioxygen in proteins from the vanillyl alcohol oxidase superfamily of flavoenzymes. We have identified an alternative gatekeeper residue that similarly controls dioxygen reactivity in the grass pollen allergen Phl p 4, a member of this superfamily that has glucose dehydrogenase activity and the highest redox potential measured in a flavoenzyme. A substitution at the alternative gatekeeper site (I153V) transformed the enzyme into an efficient oxidase by increasing dioxygen reactivity by a factor of 60,000. An inverse exchange (V169I) in the structurally related berberine bridge enzyme (BBE) decreased its dioxygen reactivity by a factor of 500. Structural and biochemical characterization of these and additional variants showed that our model enzymes possess a cavity that binds an anion and resembles the 'oxyanion hole' in the proximity of the flavin ring. We showed also that steric control of access to this site is the most important parameter affecting dioxygen reactivity in BBE-like enzymes. Analysis of flavin-dependent oxidases from other superfamilies revealed similar structural features, suggesting that dioxygen reactivity may be governed by a common mechanistic principle. DATABASE Structural data are available in PDB database under the accession numbers 4PVE, 4PVH, 4PVJ, 4PVK, 4PWB, 4PWC and 4PZF.
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Affiliation(s)
- Domen Zafred
- Institute of Biochemistry, Graz University of Technology, Austria.,Institute of Molecular Biosciences, University of Graz, Austria
| | - Barbara Steiner
- Institute of Biochemistry, Graz University of Technology, Austria
| | | | - Altijana Hromic
- Institute of Molecular Biosciences, University of Graz, Austria
| | - P Andrew Karplus
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, OR, USA
| | | | - Silvia Wallner
- Institute of Biochemistry, Graz University of Technology, Austria
| | - Peter Macheroux
- Institute of Biochemistry, Graz University of Technology, Austria
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Kopacz MM, Fraaije MW. Turning a monocovalent flavoprotein into a bicovalent flavoprotein by structure-inspired mutagenesis. Bioorg Med Chem 2014; 22:5621-7. [DOI: 10.1016/j.bmc.2014.05.051] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Revised: 05/21/2014] [Accepted: 05/22/2014] [Indexed: 10/25/2022]
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Nielsen CAF, Folly C, Hatsch A, Molt A, Schröder H, O'Connor SE, Naesby M. The important ergot alkaloid intermediate chanoclavine-I produced in the yeast Saccharomyces cerevisiae by the combined action of EasC and EasE from Aspergillus japonicus. Microb Cell Fact 2014; 13:95. [PMID: 25112180 PMCID: PMC4249865 DOI: 10.1186/s12934-014-0095-2] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2014] [Accepted: 06/24/2014] [Indexed: 02/02/2023] Open
Abstract
BACKGROUND Ergot alkaloids are a group of highly bioactive molecules produced by a number of filamentous fungi. These compounds have been intensely studied for decades, mainly due to their deleterious effects in contaminated food and feeds, but also for their beneficial pharmaceutical and agricultural applications. Biosynthesis of ergot alkaloids goes via the common intermediate chanoclavine-I, and studies of the key enzymes, EasE and EasC, involved in chanoclavine-I formation, have relied on gene complementation in fungi, whereas further characterization has been hampered by difficulties of poor EasE protein expression. In order to facilitate the study of ergot alkaloids, and eventually move towards commercial production, the early steps of the biosynthetic pathway were reconstituted in the unicellular yeast Saccharomyces cerevisiae. RESULTS The genomic sequence from an ergot alkaloid producer, Aspergillus japonicus, was used to predict the protein encoding sequences of the early ergot alkaloid pathway genes. These were cloned and expressed in yeast, resulting in de novo production of the common intermediate chanoclavine-I. This allowed further characterization of EasE and EasC, and we were able to demonstrate how the N-terminal ER targeting signal of EasE is crucial for activity in yeast. A putative, peroxisomal targeting signal found in EasC was shown to be nonessential. Overexpression of host genes pdi1 or ero1, associated with disulphide bond formation and the ER protein folding machinery, was shown to increase chanoclavine-I production in yeast. This was also the case when overexpressing host fad1, known to be involved in co-factor generation. CONCLUSIONS A thorough understanding of the enzymatic steps involved in ergot alkaloid formation is essential for commercial production and exploitation of this potent compound class. We show here that EasE and EasC are both necessary and sufficient for the production of chanoclavine-I in yeast, and we provide important new information about the involvement of ER and protein folding for proper functional expression of EasE. Moreover, by reconstructing the chanoclavine-I biosynthetic pathway in yeast we demonstrate the advantage and potential of this host, not only as a convenient model system, but also as an alternative cell factory for ergot alkaloid production.
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Schrittwieser JH, Resch V. The role of biocatalysis in the asymmetric synthesis of alkaloids. RSC Adv 2013; 3:17602-17632. [PMID: 25580241 PMCID: PMC4285126 DOI: 10.1039/c3ra42123f] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2013] [Accepted: 06/28/2013] [Indexed: 12/11/2022] Open
Abstract
Alkaloids are not only one of the most intensively studied classes of natural products, their wide spectrum of pharmacological activities also makes them indispensable drug ingredients in both traditional and modern medicine. Among the methods for their production, biotechnological approaches are gaining importance, and biocatalysis has emerged as an essential tool in this context. A number of chemo-enzymatic strategies for alkaloid synthesis have been developed over the years, in which the biotransformations nowadays take an increasingly 'central' role. This review summarises different applications of biocatalysis in the asymmetric synthesis of alkaloids and discusses how recent developments and novel enzymes render innovative and efficient chemo-enzymatic production routes possible.
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Affiliation(s)
- Joerg H Schrittwieser
- Department of Biotechnology , Delft University of Technology , Julianalaan 136 , 2628 BL Delft , The Netherlands . ; ; ; Tel: +31 152 782683
| | - Verena Resch
- Department of Biotechnology , Delft University of Technology , Julianalaan 136 , 2628 BL Delft , The Netherlands . ; ; ; Tel: +31 152 782683
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Kroutil W, Fischereder EM, Fuchs C, Lechner H, Mutti FG, Pressnitz D, Rajagopalan A, Sattler JH, Simon RC, Siirola E. Asymmetric Preparation of prim-, sec-, and tert-Amines Employing Selected Biocatalysts. Org Process Res Dev 2013; 17:751-759. [PMID: 23794796 PMCID: PMC3688330 DOI: 10.1021/op4000237] [Citation(s) in RCA: 101] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2013] [Indexed: 01/12/2023]
Abstract
This account focuses on the application of ω-transaminases, lyases, and oxidases for the preparation of amines considering mainly work from our own lab. Examples are given to access α-chiral primary amines from the corresponding ketones as well as terminal amines from primary alcohols via a two-step biocascade. 2,6-Disubstituted piperidines, as examples for secondary amines, are prepared by biocatalytical regioselective asymmetric monoamination of designated diketones followed by spontaneous ring closure and a subsequent diastereoselective reduction step. Optically pure tert-amines such as berbines and N-methyl benzylisoquinolines are obtained by kinetic resolution via an enantioselective aerobic oxidative C-C bond formation.
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Affiliation(s)
- Wolfgang Kroutil
- Department of Chemistry, University of Graz, Heinrichstrasse 28, A-8010 Graz,
Austria
- ACIB
GmbH c/o Department of Chemistry, University of Graz,
Heinrichstrasse
28, A-8010 Graz, Austria
| | - Eva-Maria Fischereder
- Department of Chemistry, University of Graz, Heinrichstrasse 28, A-8010 Graz,
Austria
| | - Christine
S. Fuchs
- ACIB
GmbH c/o Department of Chemistry, University of Graz,
Heinrichstrasse
28, A-8010 Graz, Austria
| | - Horst Lechner
- Department of Chemistry, University of Graz, Heinrichstrasse 28, A-8010 Graz,
Austria
| | - Francesco G. Mutti
- Department of Chemistry, University of Graz, Heinrichstrasse 28, A-8010 Graz,
Austria
| | - Desiree Pressnitz
- ACIB
GmbH c/o Department of Chemistry, University of Graz,
Heinrichstrasse
28, A-8010 Graz, Austria
| | - Aashrita Rajagopalan
- Department of Chemistry, University of Graz, Heinrichstrasse 28, A-8010 Graz,
Austria
| | - Johann H. Sattler
- Department of Chemistry, University of Graz, Heinrichstrasse 28, A-8010 Graz,
Austria
| | - Robert C. Simon
- Department of Chemistry, University of Graz, Heinrichstrasse 28, A-8010 Graz,
Austria
| | - Elina Siirola
- Department of Chemistry, University of Graz, Heinrichstrasse 28, A-8010 Graz,
Austria
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Prokaryotic assembly factors for the attachment of flavin to complex II. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2012; 1827:637-47. [PMID: 22985599 DOI: 10.1016/j.bbabio.2012.09.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2012] [Revised: 09/05/2012] [Accepted: 09/07/2012] [Indexed: 01/01/2023]
Abstract
Complex II (also known as Succinate dehydrogenase or Succinate-ubiquinone oxidoreductase) is an important respiratory enzyme that participates in both the tricarboxylic acid cycle and electron transport chain. Complex II consists of four subunits including a catalytic flavoprotein (SdhA), an iron-sulphur subunit (SdhB) and two hydrophobic membrane anchors (SdhC and SdhD). Complex II also contains a number of redox cofactors including haem, Fe-S clusters and FAD, which mediate electron transfer from succinate oxidation to the reduction of the mobile electron carrier ubiquinone. The flavin cofactor FAD is an important redox cofactor found in many proteins that participate in oxidation/reduction reactions. FAD is predominantly bound non-covalently to flavoproteins, with only a small percentage of flavoproteins, such as complex II, binding FAD covalently. Aside from a few examples, the mechanisms of flavin attachment have been a relatively unexplored area. This review will discuss the FAD cofactor and the mechanisms used by flavoproteins to covalently bind FAD. Particular focus is placed on the attachment of FAD to complex II with an emphasis on SdhE (a DUF339/SDH5 protein previously termed YgfY), the first protein identified as an assembly factor for FAD attachment to flavoproteins in prokaryotes. The molecular details of SdhE-dependent flavinylation of complex II are discussed and comparisons are made to known cofactor chaperones. Furthermore, an evolutionary hypothesis is proposed to explain the distribution of SdhE homologues in bacterial and eukaryotic species. Mechanisms for regulating SdhE function and how this may be linked to complex II function in different bacterial species are also discussed. This article is part of a Special Issue entitled: Respiratory complex II: Role in cellular physiology and disease.
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Wallner S, Winkler A, Riedl S, Dully C, Horvath S, Gruber K, Macheroux P. Catalytic and structural role of a conserved active site histidine in berberine bridge enzyme. Biochemistry 2012; 51:6139-47. [PMID: 22757961 PMCID: PMC3413249 DOI: 10.1021/bi300411n] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
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Berberine bridge enzyme (BBE) is a paradigm for the class
of bicovalently
flavinylated oxidases, which catalyzes the oxidative cyclization of
(S)-reticuline to (S)-scoulerine.
His174 was identified as an important active site residue because
of its role in the stabilization of the reduced state of the flavin
cofactor. It is also strictly conserved in the family of BBE-like
oxidases. Here, we present a detailed biochemical and structural characterization
of a His174Ala variant supporting its importance during catalysis
and for the structural organization of the active site. Substantial
changes in all kinetic parameters and a decrease in midpoint potential
were observed for the BBE His174Ala variant protein. Moreover, the
crystal structure of the BBE His174Ala variant showed significant
structural rearrangements compared to wild-type enzyme. On the basis
of our findings, we propose that His174 is part of a hydrogen bonding
network that stabilizes the negative charge at the N1–C2=O
locus via interaction with the hydroxyl group at C2′ of the
ribityl side chain of the flavin cofactor. Hence, replacement of this
residue with alanine reduces the stabilizing effect for the transiently
formed negative charge and results in drastically decreased kinetic
parameters as well as a lower midpoint redox potential.
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Affiliation(s)
- Silvia Wallner
- Institute of Biochemistry, Graz University of Technology, Petersgasse 12/2, A-8010 Graz, Austria
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Resch V, Schrittwieser JH, Wallner S, Macheroux P, Kroutil W. Biocatalytic Oxidative CC Bond Formation Catalysed by the Berberine Bridge Enzyme: Optimal Reaction Conditions. Adv Synth Catal 2011. [DOI: 10.1002/adsc.201100233] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Schrittwieser JH, Resch V, Wallner S, Lienhart WD, Sattler JH, Resch J, Macheroux P, Kroutil W. Biocatalytic organic synthesis of optically pure (S)-scoulerine and berbine and benzylisoquinoline alkaloids. J Org Chem 2011; 76:6703-14. [PMID: 21739961 PMCID: PMC3155283 DOI: 10.1021/jo201056f] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2011] [Indexed: 12/02/2022]
Abstract
A chemoenzymatic approach for the asymmetric total synthesis of the title compounds is described that employs an enantioselective oxidative C-C bond formation catalyzed by berberine bridge enzyme (BBE) in the asymmetric key step. This unique reaction yielded enantiomerically pure (R)-benzylisoquinoline derivatives and (S)-berbines such as the natural product (S)-scoulerine, a sedative and muscle relaxing agent. The racemic substrates rac-1 required for the biotransformation were prepared in 4-8 linear steps using either a Bischler-Napieralski cyclization or a C1-Cα alkylation approach. The chemoenzymatic synthesis was applied to the preparation of fourteen enantiomerically pure alkaloids, including the natural products (S)-scoulerine and (R)-reticuline, and gave overall yields of up to 20% over 5-9 linear steps.
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Affiliation(s)
- Joerg H. Schrittwieser
- Department of Chemistry, Organic & Bioorganic Chemistry, University of Graz, Heinrichstrasse 28, 8010 Graz, Austria
| | - Verena Resch
- Department of Chemistry, Organic & Bioorganic Chemistry, University of Graz, Heinrichstrasse 28, 8010 Graz, Austria
| | - Silvia Wallner
- Institute of Biochemistry, Graz University of Technology, Petersgasse 12, 8010 Graz, Austria
| | - Wolf-Dieter Lienhart
- Department of Chemistry, Organic & Bioorganic Chemistry, University of Graz, Heinrichstrasse 28, 8010 Graz, Austria
| | - Johann H. Sattler
- Department of Chemistry, Organic & Bioorganic Chemistry, University of Graz, Heinrichstrasse 28, 8010 Graz, Austria
| | - Jasmin Resch
- Department of Chemistry, Organic & Bioorganic Chemistry, University of Graz, Heinrichstrasse 28, 8010 Graz, Austria
| | - Peter Macheroux
- Institute of Biochemistry, Graz University of Technology, Petersgasse 12, 8010 Graz, Austria
| | - Wolfgang Kroutil
- Department of Chemistry, Organic & Bioorganic Chemistry, University of Graz, Heinrichstrasse 28, 8010 Graz, Austria
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Carlson JC, Li S, Gunatilleke SS, Anzai Y, Burr DA, Podust LM, Sherman DH. Tirandamycin biosynthesis is mediated by co-dependent oxidative enzymes. Nat Chem 2011; 3:628-33. [PMID: 21778983 PMCID: PMC3154026 DOI: 10.1038/nchem.1087] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2011] [Accepted: 06/03/2011] [Indexed: 11/23/2022]
Abstract
Elucidation of natural product biosynthetic pathways provides important insights into the assembly of potent bioactive molecules, and expands access to unique enzymes able to selectively modify complex substrates. Here, we show full reconstitution, in vitro, of an unusual multi-step oxidative cascade for post-assembly-line tailoring of tirandamycin antibiotics. This pathway involves a remarkably versatile and iterative cytochrome P450 monooxygenase (TamI) and a flavin adenine dinucleotide-dependent oxidase (TamL), which act co-dependently through the repeated exchange of substrates. TamI hydroxylates tirandamycin C (TirC) to generate tirandamycin E (TirE), a previously unidentified tirandamycin intermediate. TirE is subsequently oxidized by TamL, giving rise to the ketone of tirandamycin D (TirD), after which a unique exchange back to TamI enables successive epoxidation and hydroxylation to afford, respectively, the final products tirandamycin A (TirA) and tirandamycin B (TirB). Ligand-free, substrate- and product-bound crystal structures of bicovalently flavinylated TamL oxidase reveal a likely mechanism for the C10 oxidation of TirE.
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Affiliation(s)
- Jacob C. Carlson
- Life Sciences Institute and Departments of Medicinal Chemistry, Microbiology & Immunology and Chemistry, University of Michigan, Ann Arbor, Michigan 48109
| | - Shengying Li
- Life Sciences Institute and Departments of Medicinal Chemistry, Microbiology & Immunology and Chemistry, University of Michigan, Ann Arbor, Michigan 48109
| | - Shamila S. Gunatilleke
- Department of Pathology and Sandler Center for Drug Discovery, University of California, San Francisco, California, 94158; USA
| | - Yojiro Anzai
- Life Sciences Institute and Departments of Medicinal Chemistry, Microbiology & Immunology and Chemistry, University of Michigan, Ann Arbor, Michigan 48109
| | - Douglas A. Burr
- Life Sciences Institute and Departments of Medicinal Chemistry, Microbiology & Immunology and Chemistry, University of Michigan, Ann Arbor, Michigan 48109
| | - Larissa M. Podust
- Department of Pathology and Sandler Center for Drug Discovery, University of California, San Francisco, California, 94158; USA
| | - David H. Sherman
- Life Sciences Institute and Departments of Medicinal Chemistry, Microbiology & Immunology and Chemistry, University of Michigan, Ann Arbor, Michigan 48109
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Schrittwieser JH, Resch V, Sattler JH, Lienhart WD, Durchschein K, Winkler A, Gruber K, Macheroux P, Kroutil W. Biokatalytische enantioselektive oxidative C-C-Kupplung durch C-H-Aktivierung mit molekularem Sauerstoff. Angew Chem Int Ed Engl 2011. [DOI: 10.1002/ange.201006268] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Schrittwieser JH, Resch V, Sattler JH, Lienhart WD, Durchschein K, Winkler A, Gruber K, Macheroux P, Kroutil W. Biocatalytic enantioselective oxidative C-C coupling by aerobic C-H activation. Angew Chem Int Ed Engl 2011; 50:1068-71. [PMID: 21268196 DOI: 10.1002/anie.201006268] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2010] [Indexed: 11/09/2022]
Affiliation(s)
- Joerg H Schrittwieser
- Department of Chemistry, Organic and Bioorganic Chemistry, University of Graz, Heinrichstrasse 28, 8010 Graz, Austria
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Chang PK, Ehrlich KC, Fujii I. Cyclopiazonic acid biosynthesis of Aspergillus flavus and Aspergillus oryzae. Toxins (Basel) 2009; 1:74-99. [PMID: 22069533 PMCID: PMC3202784 DOI: 10.3390/toxins1020074] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2009] [Revised: 11/03/2009] [Accepted: 11/04/2009] [Indexed: 12/19/2022] Open
Abstract
Cyclopiazonic acid (CPA) is an indole-tetramic acid neurotoxin produced by some of the same strains of A. flavus that produce aflatoxins and by some Aspergillus oryzae strains. Despite its discovery 40 years ago, few reviews of its toxicity and biosynthesis have been reported. This review examines what is currently known about the toxicity of CPA to animals and humans, both by itself or in combination with other mycotoxins. The review also discusses CPA biosynthesis and the genetic diversity of CPA production in A. flavus/oryzae populations.
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Affiliation(s)
- Perng-Kuang Chang
- Southern Regional Research Center, Agricultural Research Service, US Department of Agriculture, 1100 Robert E. Lee Boulevard, New Orleans, LA 70124, USA; (K.E.)
| | - Kenneth C. Ehrlich
- Southern Regional Research Center, Agricultural Research Service, US Department of Agriculture, 1100 Robert E. Lee Boulevard, New Orleans, LA 70124, USA; (K.E.)
| | - Isao Fujii
- School of Pharmacy, Iwate Medical University, 2-1-1 Nishitokuta, Yahaba, Iwate 028-3694, Japan; (I.F.)
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Schäfer H, Wink M. Medicinally important secondary metabolites in recombinant microorganisms or plants: Progress in alkaloid biosynthesis. Biotechnol J 2009; 4:1684-703. [DOI: 10.1002/biot.200900229] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Winkler A, Puhl M, Weber H, Kutchan TM, Gruber K, Macheroux P. Berberine bridge enzyme catalyzes the six electron oxidation of (S)-reticuline to dehydroscoulerine. PHYTOCHEMISTRY 2009; 70:1092-1097. [PMID: 19570558 DOI: 10.1016/j.phytochem.2009.06.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2009] [Revised: 05/12/2009] [Accepted: 06/02/2009] [Indexed: 05/28/2023]
Abstract
Berberine bridge enzyme catalyzes the stereospecific oxidation and carbon-carbon bond formation of (S)-reticuline to (S)-scoulerine. In addition to this type of reactivity the enzyme can further oxidize (S)-scoulerine to the deeply red protoberberine alkaloid dehydroscoulerine albeit with a much lower rate of conversion. In the course of the four electron oxidation, no dihydroprotoberberine species intermediate was detectable suggesting that the second oxidation step leading to aromatization proceeds at a much faster rate. Performing the reaction in the presence of oxygen and under anoxic conditions did not affect the kinetics of the overall reaction suggesting no strict requirement for oxygen in the oxidation of the unstable dihydroprotoberberine intermediate. In addition to the kinetic characterization of this reaction we also present a structure of the enzyme in complex with the fully oxidized product. Combined with information available for the binding modes of (S)-reticuline and (S)-scoulerine a possible mechanism for the additional oxidation is presented. This is compared to previous reports of enzymes ((S)-tetrahydroprotoberberine oxidase and canadine oxidase) showing a similar type of reactivity in different plant species.
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Affiliation(s)
- Andreas Winkler
- Institute of Biochemistry, Graz University of Technology, Petersgasse 12/II, 8010 Graz, Austria
| | - Martin Puhl
- Institute of Biochemistry, Graz University of Technology, Petersgasse 12/II, 8010 Graz, Austria
| | - Hansjörg Weber
- Institute of Organic Chemistry, Graz University of Technology, Stremayrgasse 16, 8010 Graz, Austria
| | - Toni M Kutchan
- Donald Danforth Plant Science Center, 975 North Warson Road, St. Louis, Missouri 63132, USA
| | - Karl Gruber
- Institute of Molecular Biosciences, University of Graz, Humboldtstraße 50/III, 8010 Graz, Austria.
| | - Peter Macheroux
- Institute of Biochemistry, Graz University of Technology, Petersgasse 12/II, 8010 Graz, Austria.
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