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Shende VV, Bauman KD, Moore BS. The shikimate pathway: gateway to metabolic diversity. Nat Prod Rep 2024; 41:604-648. [PMID: 38170905 PMCID: PMC11043010 DOI: 10.1039/d3np00037k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
Covering: 1997 to 2023The shikimate pathway is the metabolic process responsible for the biosynthesis of the aromatic amino acids phenylalanine, tyrosine, and tryptophan. Seven metabolic steps convert phosphoenolpyruvate (PEP) and erythrose 4-phosphate (E4P) into shikimate and ultimately chorismate, which serves as the branch point for dedicated aromatic amino acid biosynthesis. Bacteria, fungi, algae, and plants (yet not animals) biosynthesize chorismate and exploit its intermediates in their specialized metabolism. This review highlights the metabolic diversity derived from intermediates of the shikimate pathway along the seven steps from PEP and E4P to chorismate, as well as additional sections on compounds derived from prephenate, anthranilate and the synonymous aminoshikimate pathway. We discuss the genomic basis and biochemical support leading to shikimate-derived antibiotics, lipids, pigments, cofactors, and other metabolites across the tree of life.
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Affiliation(s)
- Vikram V Shende
- Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA, 92093, USA.
| | - Katherine D Bauman
- Department of Bioengineering, Stanford University, Stanford, CA, 94305, USA
| | - Bradley S Moore
- Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA, 92093, USA.
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA, 92093, USA
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Dong L, Liu Y. Exploring the Substrate-Assisted Dehydration of Chorismate Catalyzed by Dehydratase MqnA from QM/MM Calculations: The Role of Pocket Residues and the Hydrolysis Mechanism of N17D Mutant. J Chem Inf Model 2023; 63:7499-7507. [PMID: 37970731 DOI: 10.1021/acs.jcim.3c01074] [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: 11/17/2023]
Abstract
MqnA is the first enzyme on the futalosine pathway to menaquinone, which catalyzes the dehydration of chorismate to yield 3-enolpyruvyl-benzoate (3-EPB). MqnA is also the only chorismate dehydratase known so far. In this work, based on the recently determined crystal structures, we constructed the enzyme-substrate complex models and conducted quantum mechanics/molecular mechanics (QM/MM) calculations to elucidate the reaction details of MqnA and the critical roles of pocket residues. The calculation results confirm that the MqnA-catalyzed dehydration of chorismate follows the substrate-assisted E1cb mechanism, in which the enol carboxylate in the side chain of the substrate is responsible for deprotonating the C3 of chorismate. This proton transfer process is much slower than C4-OH departure. Calculations on different mutants reveal that S86 and N17 are important for anchoring the enol carboxylate of the substrate in a favorable conformation to extract the C3-proton. The strong H-bonds formed between the enol carboxylate of chorismate and S86/N17 play a key role in stabilizing the reaction intermediate. Consistent with the experimental observations, our calculations demonstrate that the MqnA N17D mutant also shows hydrolase activity and the typical enzyme-catalyzed hydrolysis mechanism is elucidated. The protonated D17 is responsible for saturating the methylene group of chorismate to start the hydrolysis reaction. The orientation of the carboxyl group of D17 is key in determining MqnA to be a dehydratase or hydrolase.
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Affiliation(s)
- Lihua Dong
- School of Chemistry and Chemical Engineering, Qilu Normal University, Jinan, Shandong 250013, China
| | - Yongjun Liu
- School of Chemistry and Chemical Engineering, Shandong University, Jinan, Shandong 250100, China
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3
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Prasad A, Breithaupt C, Nguyen DA, Lilie H, Ziegler J, Stubbs MT. Mechanism of chorismate dehydratase MqnA, the first enzyme of the futalosine pathway, proceeds via substrate-assisted catalysis. J Biol Chem 2022; 298:102601. [PMID: 36265588 PMCID: PMC9672406 DOI: 10.1016/j.jbc.2022.102601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Revised: 10/10/2022] [Accepted: 10/12/2022] [Indexed: 11/07/2022] Open
Abstract
MqnA, the only chorismate dehydratase known so far, catalyzes the initial step in the biosynthesis of menaquinone via the futalosine pathway. Details of the MqnA reaction mechanism remain unclear. Here, we present crystal structures of Streptomyces coelicolor MqnA and its active site mutants in complex with chorismate and the product 3-enolpyruvyl-benzoate, produced during heterologous expression in Escherichia coli. Together with activity studies, our data are in line with dehydration proceeding via substrate assisted catalysis, with the enol pyruvyl group of chorismate acting as catalytic base. Surprisingly, structures of the mutant Asn17Asp with copurified ligand suggest that the enzyme converts to a hydrolase by serendipitous positioning of the carboxyl group. All complex structures presented here exhibit a closed Venus flytrap fold, with the enzyme exploiting the characteristic ligand binding properties of the fold for specific substrate binding and catalysis. The conformational rearrangements that facilitate complete burial of substrate/product, with accompanying topological changes to the enzyme surface, could foster substrate channeling within the biosynthetic pathway.
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Affiliation(s)
- Archna Prasad
- Institut für Biochemie und Biotechnologie, Charles-Tanford-Proteinzentrum, Martin-Luther-Universität – Halle-Wittenberg, Halle/Saale, Germany
| | - Constanze Breithaupt
- Institut für Biochemie und Biotechnologie, Charles-Tanford-Proteinzentrum, Martin-Luther-Universität – Halle-Wittenberg, Halle/Saale, Germany
| | - Duc-Anh Nguyen
- Institut für Biochemie und Biotechnologie, Charles-Tanford-Proteinzentrum, Martin-Luther-Universität – Halle-Wittenberg, Halle/Saale, Germany
| | - Hauke Lilie
- Institut für Biochemie und Biotechnologie, Charles-Tanford-Proteinzentrum, Martin-Luther-Universität – Halle-Wittenberg, Halle/Saale, Germany
| | - Jörg Ziegler
- Abteilung Molekulare Signalverarbeitung, Leibniz-Institut für Pflanzenbiochemie, Halle/Saale, Germany
| | - Milton T. Stubbs
- Institut für Biochemie und Biotechnologie, Charles-Tanford-Proteinzentrum, Martin-Luther-Universität – Halle-Wittenberg, Halle/Saale, Germany,For correspondence: Milton T. Stubbs
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Caffrey P, Hogan M, Song Y. New Glycosylated Polyene Macrolides: Refining the Ore from Genome Mining. Antibiotics (Basel) 2022; 11:antibiotics11030334. [PMID: 35326797 PMCID: PMC8944477 DOI: 10.3390/antibiotics11030334] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Revised: 02/25/2022] [Accepted: 03/02/2022] [Indexed: 01/26/2023] Open
Abstract
Glycosylated polyene macrolides include effective antifungal agents, such as pimaricin, nystatin, candicidin, and amphotericin B. For the treatment of systemic mycoses, amphotericin B has been described as a gold-standard antibiotic because of its potent activity against a broad spectrum of fungal pathogens, which do not readily become resistant. However, amphotericin B has severe toxic side effects, and the development of safer alternatives remains an important objective. One approach towards obtaining such compounds is to discover new related natural products. Advances in next-generation sequencing have delivered a wealth of microbial genome sequences containing polyene biosynthetic gene clusters. These typically encode a modular polyketide synthase that catalyzes the assembly of the aglycone core, a cytochrome P450 that oxidizes a methyl branch to a carboxyl group, and additional enzymes for synthesis and attachment of a single mycosamine sugar residue. In some cases, further P450s catalyze epoxide formation or hydroxylation within the macrolactone. Bioinformatic analyses have identified over 250 of these clusters. Some are predicted to encode potentially valuable new polyenes that have not been uncovered by traditional screening methods. Recent experimental studies have characterized polyenes with new polyketide backbones, previously unknown late oxygenations, and additional sugar residues that increase water-solubility and reduce hemolytic activity. Here we review these studies and assess how this new knowledge can help to prioritize silent polyene clusters for further investigation. This approach should improve the chances of discovering better antifungal antibiotics.
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Hubrich F, Müller M, Andexer JN. Chorismate- and isochorismate converting enzymes: versatile catalysts acting on an important metabolic node. Chem Commun (Camb) 2021; 57:2441-2463. [PMID: 33605953 DOI: 10.1039/d0cc08078k] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Chorismate and isochorismate represent an important branching point connecting primary and secondary metabolism in bacteria, fungi, archaea and plants. Chorismate- and isochorismate-converting enzymes are potential targets for new bioactive compounds, as well as valuable biocatalysts for the in vivo and in vitro synthesis of fine chemicals. The diversity of the products of chorismate- and isochorismate-converting enzymes is reflected in the enzymatic three-dimensional structures and molecular mechanisms. Due to the high reactivity of chorismate and its derivatives, these enzymes have evolved to be accurately tailored to their respective reaction; at the same time, many of them exhibit a fascinating flexibility regarding side reactions and acceptance of alternative substrates. Here, we give an overview of the different (sub)families of chorismate- and isochorismate-converting enzymes, their molecular mechanisms, and three-dimensional structures. In addition, we highlight important results of mutagenetic approaches that generate a broader understanding of the influence of distinct active site residues for product formation and the conversion of one subfamily into another. Based on this, we discuss to what extent the recent advances in the field might influence the general mechanistic understanding of chorismate- and isochorismate-converting enzymes. Recent discoveries of new chorismate-derived products and pathways, as well as biocatalytic conversions of non-physiological substrates, highlight how this vast field is expected to continue developing in the future.
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Affiliation(s)
- Florian Hubrich
- ETH Zurich, Institute of Microbiology, Vladimir-Prelog-Weg 4, 8093 Zurich, Switzerland.
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Shen Y, Sun F, Zhang L, Cheng Y, Zhu H, Wang SP, Jiao WH, Leadlay PF, Zhou Y, Lin HW. Biosynthesis of depsipeptides with a 3-hydroxybenzoate moiety and selective anticancer activities involves a chorismatase. J Biol Chem 2020; 295:5509-5518. [PMID: 32165500 PMCID: PMC7170507 DOI: 10.1074/jbc.ra119.010922] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Revised: 03/10/2020] [Indexed: 11/18/2022] Open
Abstract
Neoantimycins are anticancer compounds of 15-membered ring antimycin-type depsipeptides. They are biosynthesized by a hybrid multimodular protein complex of nonribosomal peptide synthetase (NRPS) and polyketide synthase (PKS), typically from the starting precursor 3-formamidosalicylate. Examining fermentation extracts of Streptomyces conglobatus, here we discovered four new neoantimycin analogs, unantimycins B-E, in which 3-formamidosalicylates are replaced by an unusual 3-hydroxybenzoate (3-HBA) moiety. Unantimycins B-E exhibited levels of anticancer activities similar to those of the chemotherapeutic drug cisplatin in human lung cancer, colorectal cancer, and melanoma cells. Notably, they mostly displayed no significant toxicity toward noncancerous cells, unlike the serious toxicities generally reported for antimycin-type natural products. Using site-directed mutagenesis and heterologous expression, we found that unantimycin productions are correlated with the activity of a chorismatase homolog, the nat-hyg5 gene, from a type I PKS gene cluster. Biochemical analysis confirmed that the catalytic activity of Nat-hyg5 generates 3-HBA from chorismate. Finally, we achieved selective production of unantimycins B and C by engineering a chassis host. On the basis of these findings, we propose that unantimycin biosynthesis is directed by the neoantimycin-producing NRPS-PKS complex and initiated with the starter unit of 3-HBA. The elucidation of the biosynthetic unantimycin pathway reported here paves the way to improve the yield of these compounds for evaluation in oncotherapeutic applications.
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Affiliation(s)
- Yaoyao Shen
- Research Center for Marine Drugs, State Key Laboratory of Oncogenes and Related Genes, Department of Pharmacy, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200127, China
| | - Fan Sun
- Research Center for Marine Drugs, State Key Laboratory of Oncogenes and Related Genes, Department of Pharmacy, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200127, China
| | - Liu Zhang
- Research Center for Marine Drugs, State Key Laboratory of Oncogenes and Related Genes, Department of Pharmacy, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200127, China
| | - Yijia Cheng
- Research Center for Marine Drugs, State Key Laboratory of Oncogenes and Related Genes, Department of Pharmacy, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200127, China
| | - Hongrui Zhu
- Research Center for Marine Drugs, State Key Laboratory of Oncogenes and Related Genes, Department of Pharmacy, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200127, China
| | - Shu-Ping Wang
- Research Center for Marine Drugs, State Key Laboratory of Oncogenes and Related Genes, Department of Pharmacy, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200127, China
| | - Wei-Hua Jiao
- Research Center for Marine Drugs, State Key Laboratory of Oncogenes and Related Genes, Department of Pharmacy, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200127, China
| | - Peter F. Leadlay
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1GA, United Kingdom
| | - Yongjun Zhou
- Research Center for Marine Drugs, State Key Laboratory of Oncogenes and Related Genes, Department of Pharmacy, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200127, China
| | - Hou-Wen Lin
- Research Center for Marine Drugs, State Key Laboratory of Oncogenes and Related Genes, Department of Pharmacy, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200127, China
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Zhang Y, Zhang H, Zheng Q. How Chorismatases Regulate Distinct Reaction Channels in a Single Conserved Active Pocket: Mechanistic Analysis with QM/MM (ONIOM) Investigations. Chemistry 2019; 25:1326-1336. [PMID: 30395358 DOI: 10.1002/chem.201804622] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Indexed: 01/12/2023]
Abstract
The FkbO and Hyg5 subfamilies of chorismatases share the same active-site architectures, but perform distinct reaction mechanisms, that is, FkbO employs a hydrolysis reaction whereas Hyg5 proceeds through an intramolecular mechanism. Despite extensive research efforts, the detailed mechanism of the product selectivity in chorismatases need to be further unmasked. In this study, the effects of the A/G residue group (A244FkbO /G240Hyg5 ) and the V/Q residue group (V209FkbO /Q201Hyg5 ) on the catalytic mechanisms are investigated by employing molecular dynamics simulations and hybrid quantum mechanical/molecular mechanical (QM/MM) calculations of the two wild-type models (FkbO/CHO and Hyg5/CHO; CHO=chorismate) and four mutants models (A244G-FkbO/CHO and G240A-Hyg5/CHO; V209Q-FkbO/CHO and Q201V-Hyg5/CHO). Our results showed that the A/G residue group mentioned by previous works would cause changes in the binding states of the substrate and the orientation of the catalytic glutamate, but only these changes affect the product selectivity in chorismatases limitedly. Interestingly, the distal V/Q residue group, which determines the internal water self-regulating ability at the active site, has significant impact on the selectivity of the catalytic mechanisms. The V/Q residue group is suggested to be an important factor to control the catalytic activities in chorismatases. The results are consistent with biochemical and structural experiments, providing novel insight into the mechanism of product selectivity in chorismatases.
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Affiliation(s)
- Yulai Zhang
- Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, International Joint Research Laboratory of, Nano-Micro Architecture Chemistry, Jilin University, Changchun, 130023, P.R. China
| | - Hongxing Zhang
- Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, International Joint Research Laboratory of, Nano-Micro Architecture Chemistry, Jilin University, Changchun, 130023, P.R. China
| | - Qingchuan Zheng
- Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, International Joint Research Laboratory of, Nano-Micro Architecture Chemistry, Jilin University, Changchun, 130023, P.R. China.,Key Laboratory for Molecular Enzymology and Engineering of the Ministry, of Education, Jilin University, Changchun, 130023, P.R. China
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Grüninger MJ, Buchholz PCF, Mordhorst S, Strack P, Müller M, Hubrich F, Pleiss J, Andexer JN. Chorismatases – the family is growing. Org Biomol Chem 2019; 17:2092-2098. [DOI: 10.1039/c8ob03038c] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A newly discovered subfamily of chorismatases catalyses the same reaction as chorismate lyases (cleavage of chorismate to 4-hydroxybenzoate), but does not suffer from product inhibition.
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Affiliation(s)
- Mads J. Grüninger
- Institute of Pharmaceutical Sciences
- University of Freiburg
- 79104 Freiburg
- Germany
| | - Patrick C. F. Buchholz
- Institute of Biochemistry and Technical Biochemistry
- University of Stuttgart
- 70569 Stuttgart
- Germany
| | - Silja Mordhorst
- Institute of Pharmaceutical Sciences
- University of Freiburg
- 79104 Freiburg
- Germany
| | - Patrick Strack
- Institute of Pharmaceutical Sciences
- University of Freiburg
- 79104 Freiburg
- Germany
| | - Michael Müller
- Institute of Pharmaceutical Sciences
- University of Freiburg
- 79104 Freiburg
- Germany
| | - Florian Hubrich
- Institute of Pharmaceutical Sciences
- University of Freiburg
- 79104 Freiburg
- Germany
| | - Jürgen Pleiss
- Institute of Biochemistry and Technical Biochemistry
- University of Stuttgart
- 70569 Stuttgart
- Germany
| | - Jennifer N. Andexer
- Institute of Pharmaceutical Sciences
- University of Freiburg
- 79104 Freiburg
- Germany
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Wang S, Bilal M, Zong Y, Hu H, Wang W, Zhang X. Development of a Plasmid-Free Biosynthetic Pathway for Enhanced Muconic Acid Production in Pseudomonas chlororaphis HT66. ACS Synth Biol 2018; 7:1131-1142. [PMID: 29608278 DOI: 10.1021/acssynbio.8b00047] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Muconic acid is a platform chemical and an important intermediate in the degradation process of a series of aromatic compounds. Herein, a plasmid-free synthetic pathway in Pseudomonas chlororaphis HT66 is constructed for the enhanced biosynthesis of muconic acid by connecting endogenous ubiquinone biosynthesis pathway with protocatechuate degradation pathway using chromosomal integration. Instead of being plasmid and inducer dependent, the engineered strains could steadily produce the high muconic acid using glycerol as a carbon source. The engineered strain HT66-MA6 achieved a 3376 mg/L muconic acid production with a yield of 187.56 mg/g glycerol via the following strategies: (1) block muconic acid conversion and enhance muconic acid efflux pumping with phenazine biosynthesis cluster; (2) increase the muconic acid precursors supply through overexpressing the rate-limiting step, and (3) coexpress the "3-dehydroshikimate-derived" route in parallel with the "4-hydroxybenzoic acid-derived" route to create a synthetic "metabolic funnel". Finally, on the basis of the glycerol feeding strategies, the muconic acid yield reached 0.122 mol/mol glycerol. The results suggest that the construction of synthetic pathway with a plasmid-free strategy in P. chlororaphis displays a high biotechnological perspective.
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Dong L, Liu Y. Comparative studies of the catalytic mechanisms of two chorismatases: CH-fkbo and CH-Hyg5. Proteins 2017; 85:1146-1158. [DOI: 10.1002/prot.25279] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2016] [Revised: 02/13/2017] [Accepted: 02/21/2017] [Indexed: 01/11/2023]
Affiliation(s)
- Lihua Dong
- School of Chemistry and Chemical Engineering; Shandong University; Jinan Shandong 250100 China
- School of Chemistry and Chemical Engineering; Qilu Normal University; Jinan Shandong 250013 China
| | - Yongjun Liu
- School of Chemistry and Chemical Engineering; Shandong University; Jinan Shandong 250100 China
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Rinkel J, Dickschat JS. Recent highlights in biosynthesis research using stable isotopes. Beilstein J Org Chem 2015; 11:2493-508. [PMID: 26734097 PMCID: PMC4685789 DOI: 10.3762/bjoc.11.271] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Accepted: 11/23/2015] [Indexed: 02/03/2023] Open
Abstract
The long and successful history of isotopic labeling experiments within natural products research has both changed and deepened our understanding of biosynthesis. As demonstrated in this article, the usage of isotopes is not at all old-fashioned, but continues to give important insights into biosynthetic pathways of secondary metabolites. This review with 85 cited references is structured by separate discussions of compounds from different classes including polyketides, non-ribosomal peptides, their hybrids, terpenoids, and aromatic compounds formed via the shikimate pathway. The text does not aim at a comprehensive overview, but instead a selection of recent important examples of isotope usage within biosynthetic studies is presented, with a special emphasis on mechanistic surprises.
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Affiliation(s)
- Jan Rinkel
- Kekulé-Institute of Organic Chemistry and Biochemistry, Gerhard-Domagk-Str. 1, 53121 Bonn, Germany
| | - Jeroen S Dickschat
- Kekulé-Institute of Organic Chemistry and Biochemistry, Gerhard-Domagk-Str. 1, 53121 Bonn, Germany
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