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Zhang D, Du W, Pan X, Lin X, Li FR, Wang Q, Yang Q, Xu HM, Dong LB. Discovery and biosynthesis of bacterial drimane-type sesquiterpenoids from Streptomyces clavuligerus. Beilstein J Org Chem 2024; 20:815-822. [PMID: 38655553 PMCID: PMC11035983 DOI: 10.3762/bjoc.20.73] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Accepted: 04/04/2024] [Indexed: 04/26/2024] Open
Abstract
Drimane-type sesquiterpenoids (DMTs) are characterized by a distinctive 6/6 bicyclic skeleton comprising the A and B rings. While DMTs are commonly found in fungi and plants, their presence in bacteria has not been reported. Moreover, the biosynthetic pathways for DMTs have been primarily elucidated in fungi, with identified P450s only acting on the B ring. In this study, we isolated and characterized three bacterial DMTs, namely 3β-hydroxydrimenol (2), 2α-hydroxydrimenol (3), and 3-ketodrimenol (4), from Streptomyces clavuligerus. Through genome mining and heterologous expression, we identified a cav biosynthetic gene cluster responsible for the biosynthesis of DMTs 2-4, along with a P450, CavA, responsible for introducing the C-2 and C-3 hydroxy groups. Furthermore, the substrate scope of CavA revealed its ability to hydroxylate drimenol analogs. This discovery not only broadens the known chemical diversity of DMTs from bacteria, but also provides new insights into DMT biosynthesis in bacteria.
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Affiliation(s)
- Dongxu Zhang
- State Key Laboratory of Natural Medicines, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing 211198, China
| | - Wenyu Du
- State Key Laboratory of Natural Medicines, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing 211198, China
| | - Xingming Pan
- State Key Laboratory of Natural Medicines, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing 211198, China
| | - Xiaoxu Lin
- State Key Laboratory of Natural Medicines, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing 211198, China
| | - Fang-Ru Li
- State Key Laboratory of Natural Medicines, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing 211198, China
| | - Qingling Wang
- State Key Laboratory of Natural Medicines, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing 211198, China
| | - Qian Yang
- State Key Laboratory of Natural Medicines, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing 211198, China
| | - Hui-Min Xu
- The Public Laboratory Platform, China Pharmaceutical University, Nanjing 211198, China
| | - Liao-Bin Dong
- State Key Laboratory of Natural Medicines, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing 211198, China
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Abstract
Covering: up to July 2023Terpene cyclases (TCs) catalyze some of the most complicated reactions in nature and are responsible for creating the skeletons of more than 95 000 terpenoid natural products. The canonical TCs are divided into two classes according to their structures, functions, and mechanisms. The class II TCs mediate acid-base-initiated cyclization reactions of isoprenoid diphosphates, terpenes without diphosphates (e.g., squalene or oxidosqualene), and prenyl moieties on meroterpenes. The past twenty years witnessed the emergence of many class II TCs, their reactions and their roles in biosynthesis. Class II TCs often act as one of the first steps in the biosynthesis of biologically active natural products including the gibberellin family of phytohormones and fungal meroterpenoids. Due to their mechanisms and biocatalytic potential, TCs elicit fervent attention in the biosynthetic and organic communities and provide great enthusiasm for enzyme engineering to construct novel and bioactive molecules. To engineer and expand the structural diversities of terpenoids, it is imperative to fully understand how these enzymes generate, precisely control, and quench the reactive carbocation intermediates. In this review, we summarize class II TCs from nature, including sesquiterpene, diterpene, triterpene, and meroterpenoid cyclases as well as noncanonical class II TCs and inspect their sequences, structures, mechanisms, and structure-guided engineering studies.
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Affiliation(s)
- Xingming Pan
- State Key Laboratory of Natural Medicines, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing 211198, China.
| | - Jeffrey D Rudolf
- Department of Chemistry, University of Florida, Gainesville, Florida 32611-7011, USA.
| | - Liao-Bin Dong
- State Key Laboratory of Natural Medicines, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing 211198, China.
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3
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DU W, YANG Q, XU H, DONG L. Drimane-type sesquiterpenoids from fungi. Chin J Nat Med 2022; 20:737-748. [DOI: 10.1016/s1875-5364(22)60190-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Indexed: 11/03/2022]
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Li FR, Lin X, Yang Q, Tan NH, Dong LB. Efficient production of clerodane and ent-kaurane diterpenes through truncated artificial pathways in Escherichia coli. Beilstein J Org Chem 2022; 18:881-888. [PMID: 35957755 PMCID: PMC9344551 DOI: 10.3762/bjoc.18.89] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Accepted: 07/15/2022] [Indexed: 11/23/2022] Open
Abstract
The clerodane and ent-kaurane diterpenoids are two typical categories of diterpenoid natural products with complicated polycyclic carbon skeletons and significant pharmacological activities. Despite exciting advances in organic chemistry, access to these skeletons is still highly challenging. Using synthetic biology to engineer microbes provides an innovative alternative to bypass synthetic challenges. In this study, we constructed two truncated artificial pathways to efficiently produce terpentetriene and ent-kaurene, two representative clerodane and ent-kaurane diterpenes, in Escherichia coli. Both pathways depend on the exogenous addition of isoprenoid alcohol to reinforce the supply of IPP and DMAPP via two sequential phosphorylation reactions. Optimization of these constructs provided terpentetriene and ent-kaurene titers of 66 ± 4 mg/L and 113 ± 7 mg/L, respectively, in shake-flask fermentation. The truncated pathways to overproduce clerodane and ent-kaurane skeletons outlined here may provide an attractive route to prepare other privileged diterpene scaffolds.
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Affiliation(s)
- Fang-Ru Li
- State Key Laboratory of Natural Medicines, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing 211198, Jiangsu, China
| | - Xiaoxu Lin
- State Key Laboratory of Natural Medicines, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing 211198, Jiangsu, China
| | - Qian Yang
- State Key Laboratory of Natural Medicines, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing 211198, Jiangsu, China
| | - Ning-Hua Tan
- State Key Laboratory of Natural Medicines, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing 211198, Jiangsu, China
| | - Liao-Bin Dong
- State Key Laboratory of Natural Medicines, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing 211198, Jiangsu, China
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5
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Cheng W, Chen M, Ohashi M, Tang Y. Biosynthesis of Terpenoid-Pyrrolobenzoxazine Hybrid Natural Product CJ-12662. Angew Chem Int Ed Engl 2022; 61:e202116928. [PMID: 35075754 DOI: 10.1002/anie.202116928] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2021] [Indexed: 11/11/2022]
Abstract
The fungal natural product CJ-12662 is a structurally complex terpene-amino acid hybrid, and is a potent anthelmintic compound. The biosynthetic pathway of CJ-12662 is elucidated based on metabolite analysis from heterologous expression. We demonstrate the terpene portion is derived from successive P450-catalyzed oxidations of amorpha-4,11-diene, while three flavin-dependent enzymes are involved in morphing the esterified tryptophan into a chlorinated pyrrolobenzoxazine, utilizing a cascaded [1,2]-Meisenheimer rearrangement.
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Affiliation(s)
- Wei Cheng
- Department of Chemical and Biomolecular Engineering, University of California, Los Angeles, CA 90095, USA.,State Key Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing, 100191, China
| | - Mengbin Chen
- Department of Chemical and Biomolecular Engineering, University of California, Los Angeles, CA 90095, USA.,Present address: Merck & Co, Inc., Rahway, NJ, USA
| | - Masao Ohashi
- Department of Chemical and Biomolecular Engineering, University of California, Los Angeles, CA 90095, USA
| | - Yi Tang
- Department of Chemical and Biomolecular Engineering, University of California, Los Angeles, CA 90095, USA.,Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095, USA
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6
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Biosynthesis of Terpenoid‐Pyrrolobenzoxazine Hybrid Natural Product CJ‐12662. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202116928] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Shen X, Wang X, Huang T, Deng Z, Lin S. Naphthoquinone-Based Meroterpenoids from Marine-Derived Streptomyces sp. B9173. Biomolecules 2020; 10:biom10081187. [PMID: 32824158 PMCID: PMC7463872 DOI: 10.3390/biom10081187] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 08/12/2020] [Accepted: 08/14/2020] [Indexed: 12/19/2022] Open
Abstract
Naphthoquinone-based meroterpenoids are hybrid polyketide-terpenoid natural products with chemical diversity and a broad range of biological activities. Here, we report the isolation of a group of naphthoquinone-containing compounds from Streptomyces sp. B9173, and their structures were elucidated by using a combination of spectroscopic techniques, including 1D, 2D NMR, and high-resolution mass (HRMS) analysis. Seven flaviogeranin congeners or intermediates, three of which were new, have been derived from common naphthoquinone backbone and subsequent oxidation, methylation, prenylation, and amino group incorporation. Both flaviogeranin B1 (1) and B (2) contain an amino group which was incorporated into the C8 of 1,3,6,8-terhydroxynaphthalene (THN). Flaviogeranin D (3) contains an intact C-geranylgeranyl residue attached to the C2 of THN, while the O-geranylgeranyl group of 2 links with the hydroxyl on the C2 site of THN. Four compounds were selected and tested for antibacterial activity and cytotoxicity, with 3 and flaviogeranin C2 (5) displaying potent activity against selected bacteria and cancer cell lines. In light of the structure features of isolated compounds and the biosynthetic genes, a biosynthetic pathway of naphthoquinone-based flaviogeranins has been proposed. These isolated compounds not only extend the structural diversity but also represent new insights into the biosynthesis of naphthoquinone-based meroterpenoids.
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Affiliation(s)
- Xinqian Shen
- State Key Laboratory of Microbial Metabolism, and Joint International Research Laboratory on Metabolic & Developmental Sciences, and School of Life Sciences & Biotechnology, Shanghai Jiao Tong University; 800 Dongchuan Rd, Shanghai 200240, China
| | - Xiaozheng Wang
- State Key Laboratory of Microbial Metabolism, and Joint International Research Laboratory on Metabolic & Developmental Sciences, and School of Life Sciences & Biotechnology, Shanghai Jiao Tong University; 800 Dongchuan Rd, Shanghai 200240, China
| | - Tingting Huang
- State Key Laboratory of Microbial Metabolism, and Joint International Research Laboratory on Metabolic & Developmental Sciences, and School of Life Sciences & Biotechnology, Shanghai Jiao Tong University; 800 Dongchuan Rd, Shanghai 200240, China
| | - Zixin Deng
- State Key Laboratory of Microbial Metabolism, and Joint International Research Laboratory on Metabolic & Developmental Sciences, and School of Life Sciences & Biotechnology, Shanghai Jiao Tong University; 800 Dongchuan Rd, Shanghai 200240, China
| | - Shuangjun Lin
- State Key Laboratory of Microbial Metabolism, and Joint International Research Laboratory on Metabolic & Developmental Sciences, and School of Life Sciences & Biotechnology, Shanghai Jiao Tong University; 800 Dongchuan Rd, Shanghai 200240, China
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8
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Searching for potent and specific antibiotics against pathogenic Helicobacter and Campylobacter strains. ACTA ACUST UNITED AC 2019; 46:409-414. [DOI: 10.1007/s10295-018-2108-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2018] [Accepted: 11/08/2018] [Indexed: 12/14/2022]
Abstract
Abstract
Menaquinone is an obligatory component of the electron-transfer pathway in microorganisms. Its biosynthetic pathway was established by pioneering studies with Escherichia coli and it was revealed to be derived from chorismate by Men enzymes. However, we identified an alternative pathway, the futalosine pathway, operating in some microorganisms including Helicobacter pylori and Campylobacter jejuni, which cause gastric carcinoma and diarrhea, respectively. Because some useful intestinal bacteria, such as lactobacilli, use the canonical pathway, the futalosine pathway is an attractive target for development of chemotherapeutics for the abovementioned pathogens. In this mini-review, we summarize compounds that inhibit Mqn enzymes involved in the futalosine pathway discovered to date.
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9
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Harnessing Underground Metabolism for Pathway Development. Trends Biotechnol 2019; 37:29-37. [DOI: 10.1016/j.tibtech.2018.08.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Revised: 07/17/2018] [Accepted: 08/06/2018] [Indexed: 01/13/2023]
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10
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Novel enzymology in futalosine-dependent menaquinone biosynthesis. Curr Opin Chem Biol 2018; 47:134-141. [DOI: 10.1016/j.cbpa.2018.09.015] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Revised: 09/13/2018] [Accepted: 09/20/2018] [Indexed: 12/12/2022]
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Two active site arginines are critical determinants of substrate binding and catalysis in MenD: a thiamine-dependent enzyme in menaquinone biosynthesis. Biochem J 2018; 475:3651-3667. [DOI: 10.1042/bcj20180548] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Revised: 10/10/2018] [Accepted: 10/17/2018] [Indexed: 11/17/2022]
Abstract
The bacterial enzyme MenD, or 2-succinyl-5-enolpyruvyl-6-hydroxy-3-cyclohexene-1-carboxylate (SEPHCHC) synthase, catalyzes an essential Stetter reaction in menaquinone (vitamin K2) biosynthesis via thiamine diphosphate (ThDP)-bound tetrahedral post-decarboxylation intermediates. The detailed mechanism of this intermediate chemistry, however, is still poorly understood, but of significant interest given that menaquinone is an essential electron transporter in many pathogenic bacteria. Here, we used site-directed mutagenesis, enzyme kinetic assays, and protein crystallography to reveal an active–inactive intermediate equilibrium in MenD catalysis and its modulation by two conserved active site arginine residues. We observed that these conserved residues play a key role in shifting the equilibrium to the active intermediate by orienting the C2-succinyl group of the intermediates through strong ionic hydrogen bonding. We found that when this interaction is moderately weakened by amino acid substitutions, the resulting proteins are catalytically competent with the C2-succinyl group taking either the active or the inactive orientation in the post-decarboxylation intermediate. When this hydrogen-bonding interaction was strongly weakened, the succinyl group was re-oriented by 180° relative to the native intermediate, resulting in the reversal of the stereochemistry at the reaction center that disabled catalysis. Interestingly, this inactive intermediate was formed with a distinct kinetic behavior, likely as a result of a non-native mode of enzyme–substrate interaction. The mechanistic insights gained from these findings improve our understanding of the new ThDP-dependent catalysis. More importantly, the non-native-binding site of the inactive MenD intermediate uncovered here provides a new target for the development of antibiotics.
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12
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Yokoyama K, Lilla EA. C-C bond forming radical SAM enzymes involved in the construction of carbon skeletons of cofactors and natural products. Nat Prod Rep 2018; 35:660-694. [PMID: 29633774 PMCID: PMC6051890 DOI: 10.1039/c8np00006a] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Covering: up to the end of 2017 C-C bond formations are frequently the key steps in cofactor and natural product biosynthesis. Historically, C-C bond formations were thought to proceed by two electron mechanisms, represented by Claisen condensation in fatty acids and polyketide biosynthesis. These types of mechanisms require activated substrates to create a nucleophile and an electrophile. More recently, increasing number of C-C bond formations catalyzed by radical SAM enzymes are being identified. These free radical mediated reactions can proceed between almost any sp3 and sp2 carbon centers, allowing introduction of C-C bonds at unconventional positions in metabolites. Therefore, free radical mediated C-C bond formations are frequently found in the construction of structurally unique and complex metabolites. This review discusses our current understanding of the functions and mechanisms of C-C bond forming radical SAM enzymes and highlights their important roles in the biosynthesis of structurally complex, naturally occurring organic molecules. Mechanistic consideration of C-C bond formation by radical SAM enzymes identifies the significance of three key mechanistic factors: radical initiation, acceptor substrate activation and radical quenching. Understanding the functions and mechanisms of these characteristic enzymes will be important not only in promoting our understanding of radical SAM enzymes, but also for understanding natural product and cofactor biosynthesis.
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Affiliation(s)
- Kenichi Yokoyama
- Department of Biochemistry, Duke University Medical Center, Durham, NC 27710, USA.
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13
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Qin M, Song H, Dai X, Chan C, Chan W, Guo Z. Single‐Turnover Kinetics Reveal a Distinct Mode of Thiamine Diphosphate‐Dependent Catalysis in Vitamin K Biosynthesis. Chembiochem 2018; 19:1514-1522. [DOI: 10.1002/cbic.201800143] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Indexed: 01/09/2023]
Affiliation(s)
- Mingming Qin
- Department of ChemistryThe Hong Kong University of Science and Technology Clear Water Bay Kowloon Hong Kong
| | - Haigang Song
- Department of ChemistryThe Hong Kong University of Science and Technology Clear Water Bay Kowloon Hong Kong
- Present address: Division of Structural BiologyWellcome Trust Centre of Human GenomicsUniversity of Oxford Roosevelt Drive Oxford OX3 7BN UK
| | - Xin Dai
- Department of ChemistryThe Hong Kong University of Science and Technology Clear Water Bay Kowloon Hong Kong
| | - Chi‐Kong Chan
- Department of ChemistryThe Hong Kong University of Science and Technology Clear Water Bay Kowloon Hong Kong
- Environmental Science ProgramThe Hong Kong University of Science and Technology Clear Water Bay Kowloon Hong Kong
| | - Wan Chan
- Department of ChemistryThe Hong Kong University of Science and Technology Clear Water Bay Kowloon Hong Kong
- Environmental Science ProgramThe Hong Kong University of Science and Technology Clear Water Bay Kowloon Hong Kong
| | - Zhihong Guo
- Department of ChemistryThe Hong Kong University of Science and Technology Clear Water Bay Kowloon Hong Kong
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Schubert T, Adrian L, Sawers RG, Diekert G. Organohalide respiratory chains: composition, topology and key enzymes. FEMS Microbiol Ecol 2018; 94:4923014. [DOI: 10.1093/femsec/fiy035] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Accepted: 02/28/2018] [Indexed: 02/07/2023] Open
Affiliation(s)
- Torsten Schubert
- Department of Applied and Ecological Microbiology, Institute of Microbiology, Friedrich Schiller University, Philosophenweg 12, D-07743 Jena, Germany
| | - Lorenz Adrian
- Department Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, Permoserstraße 15, D-04318 Leipzig, Germany
- Department of Geobiotechnology, Technische Universität Berlin, Ackerstraße 74, D-13355 Berlin, Germany
| | - R Gary Sawers
- Institute of Biology/Microbiology, Martin Luther University Halle-Wittenberg, Kurt-Mothes-Straße 3, D-06120 Halle (Saale), Germany
| | - Gabriele Diekert
- Department of Applied and Ecological Microbiology, Institute of Microbiology, Friedrich Schiller University, Philosophenweg 12, D-07743 Jena, Germany
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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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White JK, Handa S, Vankayala SL, Merkler DJ, Woodcock HL. Thiamin Diphosphate Activation in 1-Deoxy-d-xylulose 5-Phosphate Synthase: Insights into the Mechanism and Underlying Intermolecular Interactions. J Phys Chem B 2016; 120:9922-34. [PMID: 27537621 PMCID: PMC5379999 DOI: 10.1021/acs.jpcb.6b07248] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
1-Deoxy-d-xylulose 5-phosphate synthase (DXS) is a thiamin diphosphate (TDP) dependent enzyme that marks the beginning of the methylerythritol 4-phosphate isoprenoid biosynthesis pathway. The mechanism of action for DXS is still poorly understood and begins with the formation of a thiazolium ylide. This TDP activation step is thought to proceed through an intramolecular deprotonation by the 4'-aminopyrimidine ring of TDP; however, this step would occur only after an initial deprotonation of its own 4'-amino group. The mechanism of the initial deprotonation has been hypothesized, by analogy to transketolases, to occur via a histidine or an active site water molecule. Results from hybrid quantum mechanical/molecular mechanical (QM/MM) reaction path calculations reveal an ∼10 kcal/mol difference in transition state energies, favoring a water mediated mechanism over direct deprotonation by histidine. This difference was determined to be largely governed by electrostatic changes induced by conformational variations in the active site. Additionally, mutagenesis studies reveal DXS to be an evolutionarily resilient enzyme. Particularly, we hypothesize that residues H82 and H304 may act in a compensatory fashion if the other is lost due to mutation. Further, nucleus-independent chemical shifts (NICSs) and aromatic stabilization energy (ASE) calculations suggest that reduction in TDP aromaticity also serves as a factor for regulating ylide formation and controlling reactivity.
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Affiliation(s)
- Justin K. White
- Department of Chemistry, University of South Florida, 4202 E. Fowler Avenue, CHE205, Tampa, Florida 33620-5250, United States
| | - Sumit Handa
- Department of Chemistry, University of South Florida, 4202 E. Fowler Avenue, CHE205, Tampa, Florida 33620-5250, United States
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093-0332, United States
| | - Sai Lakshmana Vankayala
- Department of Chemistry, University of South Florida, 4202 E. Fowler Avenue, CHE205, Tampa, Florida 33620-5250, United States
| | - David J. Merkler
- Department of Chemistry, University of South Florida, 4202 E. Fowler Avenue, CHE205, Tampa, Florida 33620-5250, United States
| | - H. Lee Woodcock
- Department of Chemistry, University of South Florida, 4202 E. Fowler Avenue, CHE205, Tampa, Florida 33620-5250, United States
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17
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Gallagher KA, Jensen PR. Genomic insights into the evolution of hybrid isoprenoid biosynthetic gene clusters in the MAR4 marine streptomycete clade. BMC Genomics 2015; 16:960. [PMID: 26578069 PMCID: PMC4650096 DOI: 10.1186/s12864-015-2110-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Accepted: 10/19/2015] [Indexed: 01/17/2023] Open
Abstract
Background Considerable advances have been made in our understanding of the molecular genetics of secondary metabolite biosynthesis. Coupled with increased access to genome sequence data, new insight can be gained into the diversity and distributions of secondary metabolite biosynthetic gene clusters and the evolutionary processes that generate them. Here we examine the distribution of gene clusters predicted to encode the biosynthesis of a structurally diverse class of molecules called hybrid isoprenoids (HIs) in the genus Streptomyces. These compounds are derived from a mixed biosynthetic origin that is characterized by the incorporation of a terpene moiety onto a variety of chemical scaffolds and include many potent antibiotic and cytotoxic agents. Results One hundred and twenty Streptomyces genomes were searched for HI biosynthetic gene clusters using ABBA prenyltransferases (PTases) as queries. These enzymes are responsible for a key step in HI biosynthesis. The strains included 12 that belong to the ‘MAR4’ clade, a largely marine-derived lineage linked to the production of diverse HI secondary metabolites. We found ABBA PTase homologs in all of the MAR4 genomes, which averaged five copies per strain, compared with 21 % of the non-MAR4 genomes, which averaged one copy per strain. Phylogenetic analyses suggest that MAR4 PTase diversity has arisen by a combination of horizontal gene transfer and gene duplication. Furthermore, there is evidence that HI gene cluster diversity is generated by the horizontal exchange of orthologous PTases among clusters. Many putative HI gene clusters have not been linked to their secondary metabolic products, suggesting that MAR4 strains will yield additional new compounds in this structure class. Finally, we confirm that the mevalonate pathway is not always present in genomes that contain HI gene clusters and thus is not a reliable query for identifying strains with the potential to produce HI secondary metabolites. Conclusions We found that marine-derived MAR4 streptomycetes possess a relatively high genetic potential for HI biosynthesis. The combination of horizontal gene transfer, duplication, and rearrangement indicate that complex evolutionary processes account for the high level of HI gene cluster diversity in these bacteria, the products of which may provide a yet to be defined adaptation to the marine environment. Electronic supplementary material The online version of this article (doi:10.1186/s12864-015-2110-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Kelley A Gallagher
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California San Diego, 9500 Gilman Drive, La Jolla, CA, 92093-0204, USA.
| | - Paul R Jensen
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California San Diego, 9500 Gilman Drive, La Jolla, CA, 92093-0204, USA.
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18
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Kalb D, Lackner G, Rappe M, Hoffmeister D. Activity of α-Aminoadipate Reductase Depends on the N-Terminally Extending Domain. Chembiochem 2015; 16:1426-30. [DOI: 10.1002/cbic.201500190] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Indexed: 12/22/2022]
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Willrodt C, Karande R, Schmid A, Julsing MK. Guiding efficient microbial synthesis of non-natural chemicals by physicochemical properties of reactants. Curr Opin Biotechnol 2015; 35:52-62. [PMID: 25835779 DOI: 10.1016/j.copbio.2015.03.010] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Revised: 03/12/2015] [Accepted: 03/13/2015] [Indexed: 11/18/2022]
Abstract
The recent progress in sustainable chemistry and in synthetic biology increased the interest of chemical and pharmaceutical industries to implement microbial processes for chemical synthesis. However, most organisms used in biotechnological applications are not evolved by Nature for the production of hydrophobic, non-charged, volatile, or toxic compounds. In order to overcome this discrepancy, bioprocess design should consist of an integrated approach addressing pathway, cellular, reaction, and process engineering. Highlighting selected examples, we show that surprisingly often Nature provides conceptual solutions to enable chemical synthesis. Complemented by established methods from (bio)chemical and metabolic engineering, these concepts offer potential strategies yet to be explored and translated into innovative technical solutions enabling sustainable microbial production of non-natural chemicals.
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Affiliation(s)
- Christian Willrodt
- Department of Solar Materials, Helmholtz Centre for Environmental Research (UFZ), Leipzig, Germany
| | - Rohan Karande
- Department of Solar Materials, Helmholtz Centre for Environmental Research (UFZ), Leipzig, Germany
| | - Andreas Schmid
- Department of Solar Materials, Helmholtz Centre for Environmental Research (UFZ), Leipzig, Germany.
| | - Mattijs K Julsing
- Laboratory of Chemical Biotechnology, Department of Biochemical and Chemical Engineering, TU Dortmund University, Dortmund, Germany
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20
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Sato H, Hummel W, Gröger H. Cooperative Catalysis of Noncompatible Catalysts through Compartmentalization: Wacker Oxidation and Enzymatic Reduction in a One-Pot Process in Aqueous Media. Angew Chem Int Ed Engl 2015; 54:4488-92. [DOI: 10.1002/anie.201409590] [Citation(s) in RCA: 91] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2014] [Indexed: 01/22/2023]
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Sato H, Hummel W, Gröger H. Kooperative Katalyse nicht-kompatibler Katalysatoren durch Kompartimentierung: Wacker-Oxidation und enzymatische Reduktion in einem Eintopf-Verfahren im wässrigen Medium. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201409590] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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de Lorenzo V, Sekowska A, Danchin A. Chemical reactivity drives spatiotemporal organisation of bacterial metabolism. FEMS Microbiol Rev 2014; 39:96-119. [PMID: 25227915 DOI: 10.1111/1574-6976.12089] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
In this review, we examine how bacterial metabolism is shaped by chemical constraints acting on the material and dynamic layout of enzymatic networks and beyond. These are moulded not only for optimisation of given metabolic objectives (e.g. synthesis of a particular amino acid or nucleotide) but also for curbing the detrimental reactivity of chemical intermediates. Besides substrate channelling, toxicity is avoided by barriers to free diffusion (i.e. compartments) that separate otherwise incompatible reactions, along with ways for distinguishing damaging vs. harmless molecules. On the other hand, enzymes age and their operating lifetime must be tuned to upstream and downstream reactions. This time dependence of metabolic pathways creates time-linked information, learning and memory. These features suggest that the physical structure of existing biosystems, from operon assemblies to multicellular development may ultimately stem from the need to restrain chemical damage and limit the waste inherent to basic metabolic functions. This provides a new twist of our comprehension of fundamental biological processes in live systems as well as practical take-home lessons for the forward DNA-based engineering of novel biological objects.
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Affiliation(s)
- Víctor de Lorenzo
- Systems Biology Program, Centro Nacional de Biotecnología CSIC, Cantoblanco-Madrid, Spain
| | - Agnieszka Sekowska
- AMAbiotics SAS, Institut du Cerveau et de la Moëlle Épinière, Hôpital de la Pitié-Salpêtrière, Paris, France
| | - Antoine Danchin
- AMAbiotics SAS, Institut du Cerveau et de la Moëlle Épinière, Hôpital de la Pitié-Salpêtrière, Paris, France
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23
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Mehta AP, Abdelwahed SH, Mahanta N, Fedoseyenko D, Philmus B, Cooper LE, Liu Y, Jhulki I, Ealick SE, Begley TP. Radical S-adenosylmethionine (SAM) enzymes in cofactor biosynthesis: a treasure trove of complex organic radical rearrangement reactions. J Biol Chem 2014; 290:3980-6. [PMID: 25477515 DOI: 10.1074/jbc.r114.623793] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In this minireview, we describe the radical S-adenosylmethionine enzymes involved in the biosynthesis of thiamin, menaquinone, molybdopterin, coenzyme F420, and heme. Our focus is on the remarkably complex organic rearrangements involved, many of which have no precedent in organic or biological chemistry.
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Affiliation(s)
- Angad P Mehta
- From the Department of Chemistry, Texas A&M University, College Station, Texas 77843 and
| | - Sameh H Abdelwahed
- From the Department of Chemistry, Texas A&M University, College Station, Texas 77843 and
| | - Nilkamal Mahanta
- From the Department of Chemistry, Texas A&M University, College Station, Texas 77843 and
| | - Dmytro Fedoseyenko
- From the Department of Chemistry, Texas A&M University, College Station, Texas 77843 and
| | - Benjamin Philmus
- From the Department of Chemistry, Texas A&M University, College Station, Texas 77843 and
| | - Lisa E Cooper
- From the Department of Chemistry, Texas A&M University, College Station, Texas 77843 and
| | - Yiquan Liu
- From the Department of Chemistry, Texas A&M University, College Station, Texas 77843 and
| | - Isita Jhulki
- From the Department of Chemistry, Texas A&M University, College Station, Texas 77843 and
| | - Steven E Ealick
- the Department of Chemistry, Cornell University, Ithaca, New York 14850
| | - Tadhg P Begley
- From the Department of Chemistry, Texas A&M University, College Station, Texas 77843 and
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24
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Cooper LE, Fedoseyenko D, Abdelwahed SH, Kim SH, Dairi T, Begley TP. In vitro reconstitution of the radical S-adenosylmethionine enzyme MqnC involved in the biosynthesis of futalosine-derived menaquinone. Biochemistry 2013; 52:4592-4. [PMID: 23763543 PMCID: PMC3855634 DOI: 10.1021/bi400498d] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The radical S-adenosylmethionine enzyme MqnC catalyzes conversion of dehypoxanthine futalosine (DHFL) to the unique spiro compound cyclic DHFL in the futalosine pathway for menaquinone biosynthesis. This study describes the in vitro reconstitution of [4Fe-4S] cluster-dependent MqnC activity and identifies the site of abstraction of a hydrogen atom from DHFL by the adenosyl radical.
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Affiliation(s)
| | | | | | | | | | - Tadhg P. Begley
- Corresponding Author, Prof. Tadhg P. Begley, Department of Chemistry, Texas A&M University, College Station, TX 77842, , Phone: (979) 862-4091
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Johnston JM, Jiang M, Guo Z, Baker EN. Crystal structures of E. coli native MenH and two active site mutants. PLoS One 2013; 8:e61325. [PMID: 23637813 PMCID: PMC3630204 DOI: 10.1371/journal.pone.0061325] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2012] [Accepted: 03/08/2013] [Indexed: 11/17/2022] Open
Abstract
Recent revision of the biosynthetic pathway for menaquinone has led to the discovery of a previously unrecognized enzyme 2-succinyl-6-hydroxy-2,4-cyclohexadiene-1-carboxylate synthase, also known as MenH. This enzyme has an α/β hydrolase fold with a catalytic triad comprising Ser86, His232, and Asp210. Mutational studies identified a number of conserved residues of importance to activity, and modeling further implicated the side chains of Tyr85 and Trp147 in formation of a non-standard oxyanion hole. We have solved the structure of E. coli MenH (EcMenH) at 2.75 Å resolution, together with the structures of the active site mutant proteins Tyr85Phe and Arg124Ala, both at 2.5 Å resolution. EcMenH has the predicted α/β hydrolase fold with its core α/β domain capped by a helical lid. The active site, a long groove beneath the cap, contains a number of conserved basic residues and is found to bind exogeneous anions, modeled as sulfate and chloride, in all three crystal structures. Docking studies with the MenH substrate and a transition state model indicate that the bound anions mark the binding sites for anionic groups on the substrate. The docking studies, and careful consideration of the active site geometry, further suggest that the oxyanion hole is of a conventional nature, involving peptide NH groups, rather than the proposed site involving Tyr85 and Trp147. This is in accord with conclusions from the structure of S. aureus MenH. Comparisons with the latter do, however, indicate differences in the periphery of the active site that could be of relevance to selective inhibition of MenH enzymes.
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Affiliation(s)
- Jodie M Johnston
- Maurice Wilkins Centre and School of Biological Sciences, University of Auckland, Auckland, New Zealand
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26
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Posehn SE, Kim SY, Wee AGH, Suh DY. Mapping the mechanism of the resorcinol ring formation catalyzed by ArsB, a type III polyketide synthase from Azotobacter vinelandii. Chembiochem 2012; 13:2212-7. [PMID: 22961888 DOI: 10.1002/cbic.201200346] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2012] [Indexed: 02/05/2023]
Abstract
Who's first? Aldol cyclization occurs before hydrolysis in the resorcinol ring formation catalyzed by the type III polyketide synthase, ArsB. Synthetic C(20)-TKA was not converted to alkylresorcinol by ArsB, but rather inhibited the enzyme activity, thus indicating that C(20)-TKA is not an intermediate in ArsB-catalyzed alkylresorcinol formation.
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Affiliation(s)
- Sarah E Posehn
- Department of Chemistry and Biochemistry, University of Regina, 3737 Wascana Parkway, Regina, SK S4S 0A2, Canada
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27
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Different biosynthetic pathways to fosfomycin in Pseudomonas syringae and Streptomyces species. Antimicrob Agents Chemother 2012; 56:4175-83. [PMID: 22615277 DOI: 10.1128/aac.06478-11] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Fosfomycin is a wide-spectrum antibiotic that is used clinically to treat acute cystitis in the United States. The compound is produced by several strains of streptomycetes and pseudomonads. We sequenced the biosynthetic gene cluster responsible for fosfomycin production in Pseudomonas syringae PB-5123. Surprisingly, the biosynthetic pathway in this organism is very different from that in Streptomyces fradiae and Streptomyces wedmorensis. The pathways share the first and last steps, involving conversion of phosphoenolpyruvate to phosphonopyruvate (PnPy) and 2-hydroxypropylphosphonate (2-HPP) to fosfomycin, respectively, but the enzymes converting PnPy to 2-HPP are different. The genome of P. syringae PB-5123 lacks a gene encoding the PnPy decarboxylase found in the Streptomyces strains. Instead, it contains a gene coding for a citrate synthase-like enzyme, Psf2, homologous to the proteins that add an acetyl group to PnPy in the biosynthesis of FR-900098 and phosphinothricin. Heterologous expression and purification of Psf2 followed by activity assays confirmed the proposed activity of Psf2. Furthermore, heterologous production of fosfomycin in Pseudomonas aeruginosa from a fosmid encoding the fosfomycin biosynthetic cluster from P. syringae PB-5123 confirmed that the gene cluster is functional. Therefore, two different pathways have evolved to produce this highly potent antimicrobial agent.
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Morgat A, Coissac E, Coudert E, Axelsen KB, Keller G, Bairoch A, Bridge A, Bougueleret L, Xenarios I, Viari A. UniPathway: a resource for the exploration and annotation of metabolic pathways. Nucleic Acids Res 2011; 40:D761-9. [PMID: 22102589 PMCID: PMC3245108 DOI: 10.1093/nar/gkr1023] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
UniPathway (http://www.unipathway.org) is a fully manually curated resource for the representation and annotation of metabolic pathways. UniPathway provides explicit representations of enzyme-catalyzed and spontaneous chemical reactions, as well as a hierarchical representation of metabolic pathways. This hierarchy uses linear subpathways as the basic building block for the assembly of larger and more complex pathways, including species-specific pathway variants. All of the pathway data in UniPathway has been extensively cross-linked to existing pathway resources such as KEGG and MetaCyc, as well as sequence resources such as the UniProt KnowledgeBase (UniProtKB), for which UniPathway provides a controlled vocabulary for pathway annotation. We introduce here the basic concepts underlying the UniPathway resource, with the aim of allowing users to fully exploit the information provided by UniPathway.
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Affiliation(s)
- Anne Morgat
- Swiss-Prot Group, SIB Swiss Institute of Bioinformatics, CMU, 1 rue Michel-Servet, CH-1211 Geneva 4, Switzerland.
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29
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Chang WC, Xiao Y, Liu HW, Liu P. Mechanistic studies of an IspH-catalyzed reaction: implications for substrate binding and protonation in the biosynthesis of isoprenoids. Angew Chem Int Ed Engl 2011; 50:12304-7. [PMID: 22025241 DOI: 10.1002/anie.201104124] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2011] [Indexed: 11/07/2022]
Affiliation(s)
- Wei-chen Chang
- Division of Medicinal Chemistry, College of Pharmacy and Department of Chemistry and Biochemistry, University of Texas at Austin, Austin, TX 78712, USA
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30
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Chang WC, Xiao Y, Liu HW, Liu P. Mechanistic Studies of an IspH-Catalyzed Reaction: Implications for Substrate Binding and Protonation in the Biosynthesis of Isoprenoids. Angew Chem Int Ed Engl 2011. [DOI: 10.1002/ange.201104124] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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31
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Barona-Gómez F, Cruz-Morales P, Noda-García L. What can genome-scale metabolic network reconstructions do for prokaryotic systematics? Antonie van Leeuwenhoek 2011; 101:35-43. [PMID: 22016333 DOI: 10.1007/s10482-011-9655-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2011] [Accepted: 10/07/2011] [Indexed: 11/24/2022]
Abstract
It has recently been proposed that in addition to Nomenclature, Classification and Identification, Comprehending Microbial Diversity may be considered as the fourth tenet of microbial systematics [Staley JT (2010) The Bulletin of BISMiS, 1(1): 1-5]. As this fourth goal implies a fundamental understanding of microbial speciation, this perspective article argues that translation of bacterial genome sequences into metabolic features may contribute to the development of modern polyphasic taxonomic approaches. Genome-scale metabolic network reconstructions (GSMRs), which are the result of computationally predicted and experimentally confirmed stoichiometric matrices incorporating all enzyme and metabolite components encoded by a genome sequence, provide a platform that can illustrate bacterial speciation. As the topology and the composition of GSMRs are expected to be the result of adaptive evolution, the features of these networks may provide the prokaryotic taxonomist with novel tools for reaching the fourth tenet of microbial systematics. Through selected examples from the Actinobacteria, which have been inferred from GSMRs and experimentally confirmed after phenotypic characterisation, it will be shown that this level of information can be incorporated into modern polyphasic taxonomic approaches. In conclusion, three specific examples are illustrated to show how GSMRs will revolutionize prokaryotic systematics, as has previously occurred in many other fields of microbiology.
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Affiliation(s)
- Francisco Barona-Gómez
- Evolution of Metabolic Diversity Laboratory, Laboratorio Nacional de Genómica para la Biodiversidad (Langebio), CINVESTAV-IPN, Km 9.6 Libramiento Norte, Carretera Irapuato-León, Irapuato, Mexico.
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