1
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Ehinger FJ, Hertweck C. Biosynthesis and recruitment of reactive amino acids in nonribosomal peptide assembly lines. Curr Opin Chem Biol 2024; 81:102494. [PMID: 38936328 DOI: 10.1016/j.cbpa.2024.102494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Revised: 05/29/2024] [Accepted: 06/05/2024] [Indexed: 06/29/2024]
Abstract
Reactive amino acid side chains play important roles in the binding of peptides to specific targets. In addition, their reactivity enables selective peptide conjugation and functionalization for pharmaceutical purposes. Diverse reactive amino acids are incorporated into nonribosomal peptides, which serve as a source for drug candidates. Notable examples include (poly)unsaturated (enamine, alkyne, and furyl) and halogenated residues, strained carbacycles (cyclopropyl and cyclopropanol), small heterocycles (oxirane and aziridine), and reactive N-N functionalities (hydrazones, diazo compounds, and diazeniumdiolates). Their biosynthesis requires diverse biocatalysts for sophisticated reaction mechanisms. Several avenues have been identified for their incorporation into peptides, the recruitment by adenylation domains or ligases, on-line modifications, and enzymatic tailoring reactions. Combined with protein engineering approaches, this knowledge provides new opportunities in synthetic biology and bioorthogonal chemistry.
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Affiliation(s)
- Friedrich Johannes Ehinger
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Beutenbergstr. 11a, 07745 Jena, Germany
| | - Christian Hertweck
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Beutenbergstr. 11a, 07745 Jena, Germany; Institute of Microbiology, Faculty of Biological Sciences, Friedrich Schiller University Jena, 07743 Jena, Germany.
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2
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Fiedler J, Trottmann F, Ishida K, Ishida-Ito M, Hertweck C. Direct α-Hydroxy Acid Loading onto a Bacterial Thiotemplate Assembly Line via a Multienzyme Gateway. Angew Chem Int Ed Engl 2024; 63:e202405165. [PMID: 38728443 DOI: 10.1002/anie.202405165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2024] [Revised: 05/06/2024] [Accepted: 05/09/2024] [Indexed: 05/12/2024]
Abstract
Various nonribosomal peptide synthetases (NRPSs) create structural and functional diversity by incorporating α-hydroxy acids into peptide backbones. Trigonic acid, an unusual cyclopropanol-substituted hydroxy acid, is the source of the molecular warhead of malleicyprol, a critical virulence factor of human and animal pathogens of the Burkholderia pseudomallei (BP) group. The process of selecting and loading this building block remained enigmatic as the NRPS module designated for this task is incomplete. Using a combination of bioinformatics, mutational analyses, targeted metabolomics, and in vitro biochemical assays, we show that two trans-acting enzymes are required to load this central building block onto the modular assembly line. An adenylation-thiolation didomain enzyme (BurJ) activates trigonic acid, followed by the translocation of the enzyme-bound α-hydroxy acid thioester by an FkbH-like protein with a mutated phosphatase domain (BurH). This specialized gateway is the first reported direct loading of an α-hydroxy acid onto a bona fide NRPS module in bacteria and expands the synthetic biology toolbox for the site-specific incorporation of non-canonical building blocks. Moreover, insight into the biochemical basis of virulence factor biosynthesis can provide a foundation for developing enzyme inhibitors as anti-virulence therapeutics against BP pathogen infections.
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Affiliation(s)
- Jonas Fiedler
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Product, Research and Infection Biology (HKI), Beutenbergstraße 11a, 07745, Jena, Germany
| | - Felix Trottmann
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Product, Research and Infection Biology (HKI), Beutenbergstraße 11a, 07745, Jena, Germany
| | - Keishi Ishida
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Product, Research and Infection Biology (HKI), Beutenbergstraße 11a, 07745, Jena, Germany
| | - Mie Ishida-Ito
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Product, Research and Infection Biology (HKI), Beutenbergstraße 11a, 07745, Jena, Germany
| | - Christian Hertweck
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Product, Research and Infection Biology (HKI), Beutenbergstraße 11a, 07745, Jena, Germany
- Natural Product Chemistry, Faculty of Biological Sciences, Friedrich Schiller University Jena, 07743, Jena, Germany
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3
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Little RF, Trottmann F, Hashizume H, Preissler M, Unger S, Sawa R, Kries H, Pidot S, Igarashi M, Hertweck C. Analysis of the Valgamicin Biosynthetic Pathway Reveals a General Mechanism for Cyclopropanol Formation across Diverse Natural Product Scaffolds. ACS Chem Biol 2024; 19:660-668. [PMID: 38358369 DOI: 10.1021/acschembio.3c00648] [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: 02/16/2024]
Abstract
Cyclopropanol rings are highly reactive and may function as molecular "warheads" that affect natural product bioactivity. Yet, knowledge on their biosynthesis is limited. Using gene cluster analyses, isotope labeling, and in vitro enzyme assays, we shed first light on the biosynthesis of the cyclopropanol-substituted amino acid cleonine, a residue in the antimicrobial depsipeptide valgamicin C and the cytotoxic glycopeptide cleomycin A2. We decipher the biosynthetic origin of valgamicin C and show that the cleonine cyclopropanol ring is derived from dimethylsulfoniopropionate (DMSP). Furthermore, we demonstrate that part of the biosynthesis is analogous to the formation of malleicyprol polyketides in pathogenic bacteria. By genome mining and metabolic profiling, we identify the potential to produce cyclopropanol rings in other bacterial species. Our results reveal a general mechanism for cyclopropyl alcohol biosynthesis across diverse natural products that may be harnessed for bioengineering and drug discovery.
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Affiliation(s)
- Rory F Little
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Beutenbergstraße 11a, 07745 Jena, Germany
| | - Felix Trottmann
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Beutenbergstraße 11a, 07745 Jena, Germany
| | - Hideki Hashizume
- Laboratory of Microbiology, Institute of Microbial Chemistry (BIKAKEN), 3-14-23 Kamiosaki, Shinagawa-ku, Tokyo 141-0021, Japan
| | - Miriam Preissler
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Beutenbergstraße 11a, 07745 Jena, Germany
| | - Sandra Unger
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Beutenbergstraße 11a, 07745 Jena, Germany
| | - Ryuichi Sawa
- Laboratory of Molecular Structure Analysis, Institute of Microbial Chemistry (BIKAKEN), 3-14-23 Kamiosaki, Shinagawa-ku, Tokyo 141-0021, Japan
| | - Hajo Kries
- Biosynthetic Design of Natural Products, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Beutenbergstraße 11a, 07745 Jena, Germany
| | - Sacha Pidot
- Department of Microbiology and Immunology, Doherty Institute, 792 Elizabeth Street, Melbourne 3000, Australia
| | - Masayuki Igarashi
- Laboratory of Microbiology, Institute of Microbial Chemistry (BIKAKEN), 3-14-23 Kamiosaki, Shinagawa-ku, Tokyo 141-0021, Japan
| | - Christian Hertweck
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Beutenbergstraße 11a, 07745 Jena, Germany
- Institute of Microbiology, Faculty of Biological Sciences, Friedrich Schiller University Jena, 07743 Jena, Germany
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4
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Saad H, Majer T, Bhattarai K, Lampe S, Nguyen DT, Kramer M, Straetener J, Brötz-Oesterhelt H, Mitchell DA, Gross H. Bioinformatics-guided discovery of biaryl-linked lasso peptides. Chem Sci 2023; 14:13176-13183. [PMID: 38023510 PMCID: PMC10664482 DOI: 10.1039/d3sc02380j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Accepted: 10/27/2023] [Indexed: 12/01/2023] Open
Abstract
Lasso peptides are a class of ribosomally synthesized and post-translationally modified peptides (RiPPs) that feature an isopeptide bond and a distinct lariat fold. A growing number of secondary modifications have been described that further decorate lasso peptide scaffolds. Using genome mining, we have discovered a pair of lasso peptide biosynthetic gene clusters (BGCs) that include cytochrome P450 genes. Using mass spectrometry, stable isotope incorporation, and extensive 2D-NMR spectrometry, we report the structural characterization of two unique examples of (C-N) biaryl-linked lasso peptides. Nocapeptin A, from Nocardia terpenica, is tailored with a Trp-Tyr crosslink, while longipepetin A, from Longimycelium tulufanense, features a Trp-Trp linkage. Besides the unusual bicyclic frame, a Met of longipepetin A undergoes S-methylation to yield a trivalent sulfonium, a heretofore unprecedented RiPP modification. A bioinformatic survey revealed additional lasso peptide BGCs containing P450 enzymes which await future characterization. Lastly, nocapeptin A bioactivity was assessed against a panel of human and bacterial cell lines with modest growth-suppression activity detected towards Micrococcus luteus.
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Affiliation(s)
- Hamada Saad
- Department of Pharmaceutical Biology, Institute of Pharmaceutical Sciences, University of Tübingen Auf der Morgenstelle 8 72076 Tübingen Germany
- Department of Chemistry and the Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign Urbana Illinois 61801 USA
| | - Thomas Majer
- Department of Pharmaceutical Biology, Institute of Pharmaceutical Sciences, University of Tübingen Auf der Morgenstelle 8 72076 Tübingen Germany
| | - Keshab Bhattarai
- Department of Pharmaceutical Biology, Institute of Pharmaceutical Sciences, University of Tübingen Auf der Morgenstelle 8 72076 Tübingen Germany
| | - Sarah Lampe
- Department of Pharmaceutical Biology, Institute of Pharmaceutical Sciences, University of Tübingen Auf der Morgenstelle 8 72076 Tübingen Germany
| | - Dinh T Nguyen
- Department of Chemistry and the Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign Urbana Illinois 61801 USA
| | - Markus Kramer
- Institute of Organic Chemistry, University of Tübingen Auf der Morgenstelle 18 72076 Tübingen Germany
| | - Jan Straetener
- Department of Microbial Bioactive Compounds, Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen Auf der Morgenstelle 28 72076 Tübingen Germany
| | - Heike Brötz-Oesterhelt
- Department of Microbial Bioactive Compounds, Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen Auf der Morgenstelle 28 72076 Tübingen Germany
- Cluster of Excellence: EXC 2124: Controlling Microbes to Fight Infection, University of Tübingen Tübingen Germany
| | - Douglas A Mitchell
- Department of Chemistry and the Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign Urbana Illinois 61801 USA
| | - Harald Gross
- Department of Pharmaceutical Biology, Institute of Pharmaceutical Sciences, University of Tübingen Auf der Morgenstelle 8 72076 Tübingen Germany
- Cluster of Excellence: EXC 2124: Controlling Microbes to Fight Infection, University of Tübingen Tübingen Germany
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5
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Büttner H, Hörl J, Krabbe J, Hertweck C. Discovery and Biosynthesis of Anthrochelin, a Growth-Promoting Metallophore of the Human Pathogen Luteibacter anthropi. Chembiochem 2023; 24:e202300322. [PMID: 37191164 DOI: 10.1002/cbic.202300322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Revised: 05/15/2023] [Accepted: 05/16/2023] [Indexed: 05/17/2023]
Abstract
Various human pathogens have emerged from environmental strains by adapting to higher growth temperatures and the ability to produce virulence factors. A remarkable example of a pathoadapted bacterium is found in the genus Luteibacter, which typically comprises harmless soil microbes, yet Luteibacter anthropi was isolated from the blood of a diseased child. Up until now, nothing has been known about the specialized metabolism of this pathogen. By comparative genome analyses we found that L. anthropi has a markedly higher biosynthetic potential than other bacteria of this genus and uniquely bears an NRPS gene locus tentatively coding for the biosynthesis of a metallophore. By metabolic profiling, stable isotope labeling, and NMR investigation of a gallium complex, we identified a new family of salicylate-derived nonribosomal peptides named anthrochelins A-D. Surprisingly, anthrochelins feature a C-terminal homocysteine tag, which might be introduced during peptide termination. Mutational analyses provided insight into the anthrochelin assembly and revealed the unexpected involvement of a cytochrome P450 monooxygenase in oxazole formation. Notably, this heterocycle plays a key role in the binding of metals, especially copper(II). Bioassays showed that anthrochelin significantly promotes the growth of L. anthropi in the presence of low and high copper concentrations, which occur during infections.
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Affiliation(s)
- Hannah Büttner
- Leibniz Institute for Natural Product Research and Infection, Biology, HKI, Dept. of Biomolecular Chemistry, Beutenbergstrasse 11a, 07745, Jena, Germany
| | - Johannes Hörl
- Leibniz Institute for Natural Product Research and Infection, Biology, HKI, Dept. of Biomolecular Chemistry, Beutenbergstrasse 11a, 07745, Jena, Germany
| | - Jana Krabbe
- Leibniz Institute for Natural Product Research and Infection, Biology, HKI, Dept. of Biomolecular Chemistry, Beutenbergstrasse 11a, 07745, Jena, Germany
| | - Christian Hertweck
- Leibniz Institute for Natural Product Research and Infection, Biology, HKI, Dept. of Biomolecular Chemistry, Beutenbergstrasse 11a, 07745, Jena, Germany
- Institute of Microbiology, Faculty of Biological Sciences, Friedrich Schiller University Jena, 07743, Jena, Germany
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6
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Trottmann F, Fiedler J, Ishida K, Ishida-Ito M, Little RF, Hertweck C. Bacterial Pathogen Channels Medium-Sized Fatty Acids into Malleicyprol Biosynthesis. ACS Chem Biol 2023; 18:1557-1563. [PMID: 37319349 DOI: 10.1021/acschembio.3c00188] [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: 06/17/2023]
Abstract
Bacterial pathogens of the Burkholderia pseudomallei (BP) group cause life-threatening infections in both humans and animals. Critical for the virulence of these often antibiotic-resistant pathogens is the polyketide hybrid metabolite malleicyprol, which features two chains, a short cyclopropanol-substituted chain and a long hydrophobic alkyl chain. The biosynthetic origin of the latter has remained unknown. Here, we report the discovery of novel overlooked malleicyprol congeners with varied chain lengths and identify medium-sized fatty acids as polyketide synthase (PKS) starter units that constitute the hydrophobic carbon tails. Mutational and biochemical analyses show that a designated coenzyme A-independent fatty acyl-adenylate ligase (FAAL, BurM) is essential for recruiting and activating fatty acids in malleicyprol biosynthesis. In vitro reconstitution of the BurM-catalyzed PKS priming reaction and analysis of ACP-bound building blocks reveal a key role of BurM in the toxin assembly. Insights into the function and role of BurM hold promise for the development of enzyme inhibitors as novel antivirulence therapeutics to combat infections with BP pathogens.
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Affiliation(s)
- Felix Trottmann
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Beutenbergstraße 11a, 07745 Jena, Germany
| | - Jonas Fiedler
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Beutenbergstraße 11a, 07745 Jena, Germany
| | - Keishi Ishida
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Beutenbergstraße 11a, 07745 Jena, Germany
| | - Mie Ishida-Ito
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Beutenbergstraße 11a, 07745 Jena, Germany
| | - Rory F Little
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Beutenbergstraße 11a, 07745 Jena, Germany
| | - Christian Hertweck
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Beutenbergstraße 11a, 07745 Jena, Germany
- Natural Product Chemistry, Faculty of Biological Sciences, Friedrich Schiller University Jena, 07743 Jena, Germany
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7
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Chuang L, Liu S, Franke J. Post-Cyclization Skeletal Rearrangements in Plant Triterpenoid Biosynthesis by a Pair of Branchpoint Isomerases. J Am Chem Soc 2023; 145:5083-5091. [PMID: 36821810 PMCID: PMC9999417 DOI: 10.1021/jacs.2c10838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
Triterpenoids possess potent biological activities, but their polycyclic skeletons are challenging to synthesize. The skeletal diversity of triterpenoids in plants is generated by oxidosqualene cyclases based on epoxide-triggered cationic rearrangement cascades. Normally, triterpenoid skeletons then remain unaltered during subsequent tailoring steps. In contrast, the highly modified triterpenoids found in Sapindales plants imply the existence of post-cyclization skeletal rearrangement enzymes that have not yet been found. We report here a biosynthetic pathway in Sapindales plants for the modification of already cyclized tirucallane triterpenoids, controlling the pathway bifurcation between different plant triterpenoid classes. Using a combination of bioinformatics, heterologous expression in plants and chemical analyses, we identified a cytochrome P450 monooxygenase and two isomerases which harness the epoxidation-rearrangement biosynthetic logic of triterpene cyclizations for modifying the tirucallane scaffold. The two isomerases share the same epoxide substrate made by the cytochrome P450 monooxygenase CYP88A154, but generate two different rearrangement products, one containing a cyclopropane ring. Our findings reveal a process for skeletal rearrangements of triterpenoids in nature that expands their scaffold diversity after the initial cyclization. In addition, the enzymes described here are crucial for the biotechnological production of limonoid, quassinoid, apoprotolimonoid, and glabretane triterpenoids.
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Affiliation(s)
- Ling Chuang
- Centre of Biomolecular Drug Research, Leibniz University Hannover, Schneiderberg 38, 30167 Hannover, Germany
| | - Shenyu Liu
- Centre of Biomolecular Drug Research, Leibniz University Hannover, Schneiderberg 38, 30167 Hannover, Germany
| | - Jakob Franke
- Centre of Biomolecular Drug Research, Leibniz University Hannover, Schneiderberg 38, 30167 Hannover, Germany.,Institute of Botany, Leibniz University Hannover, Herrenhäuser Str. 2, 30419 Hannover, Germany
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8
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Saad H, Majer T, Bhattarai K, Lampe S, Nguyen DT, Kramer M, Straetener J, Brötz-Oesterhelt H, Mitchell DA, Gross H. Bioinformatics-Guided Discovery of Biaryl-Tailored Lasso Peptides. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.06.531328. [PMID: 36945544 PMCID: PMC10028836 DOI: 10.1101/2023.03.06.531328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/11/2023]
Abstract
Lasso peptides are a class of ribosomally synthesized and post-translationally modified peptides (RiPPs) that feature an isopeptide bond and a distinct lariat fold. A growing number of secondary modifications have been described that further decorate lasso peptide scaffolds. Using genome mining, we have discovered a pair of lasso peptide biosynthetic gene clusters (BGCs) that include cytochrome P450 genes. Here, we report the structural characterization of two unique examples of (C-N) biaryl-containing lasso peptides. Nocapeptin A, from Nocardia terpenica, is tailored with Trp-Tyr crosslink while longipepetin A, from Longimycelium tulufanense, features Trp-Trp linkage. Besides the unusual bicyclic frame, longipepetin A receives an S-methylation by a new Met methyltransferase resulting in unprecedented sulfonium-bearing RiPP. Our bioinformatic survey revealed P450(s) and further maturating enzyme(s)-containing lasso BGCs awaiting future characterization.
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Affiliation(s)
- Hamada Saad
- Department of Pharmaceutical Biology, Institute of Pharmaceutical Sciences, University of Tübingen, Auf der Morgenstelle 8, 72076 Tübingen (Germany)
- Department of Chemistry and the Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana–Champaign, Urbana, Illinois 61801 (United States)
| | - Thomas Majer
- Department of Pharmaceutical Biology, Institute of Pharmaceutical Sciences, University of Tübingen, Auf der Morgenstelle 8, 72076 Tübingen (Germany)
| | - Keshab Bhattarai
- Department of Pharmaceutical Biology, Institute of Pharmaceutical Sciences, University of Tübingen, Auf der Morgenstelle 8, 72076 Tübingen (Germany)
| | - Sarah Lampe
- Department of Pharmaceutical Biology, Institute of Pharmaceutical Sciences, University of Tübingen, Auf der Morgenstelle 8, 72076 Tübingen (Germany)
| | - Dinh T. Nguyen
- Department of Chemistry and the Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana–Champaign, Urbana, Illinois 61801 (United States)
| | - Markus Kramer
- Institute of Organic Chemistry, University of Tübingen, Auf der Morgenstelle 18, 72076 Tübingen (Germany)
| | - Jan Straetener
- Department of Microbial Bioactive Compounds, Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Auf der Morgenstelle 28, 72076 Tübingen (Germany)
| | - Heike Brötz-Oesterhelt
- Department of Microbial Bioactive Compounds, Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Auf der Morgenstelle 28, 72076 Tübingen (Germany)
| | - Douglas A. Mitchell
- Department of Chemistry and the Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana–Champaign, Urbana, Illinois 61801 (United States)
| | - Harald Gross
- Department of Pharmaceutical Biology, Institute of Pharmaceutical Sciences, University of Tübingen, Auf der Morgenstelle 8, 72076 Tübingen (Germany)
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9
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Biermann F, Wenski SL, Helfrich EJN. Navigating and expanding the roadmap of natural product genome mining tools. Beilstein J Org Chem 2022; 18:1656-1671. [PMID: 36570563 PMCID: PMC9749553 DOI: 10.3762/bjoc.18.178] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Accepted: 11/02/2022] [Indexed: 12/12/2022] Open
Abstract
Natural products are structurally highly diverse and exhibit a wide array of biological activities. As a result, they serve as an important source of new drug leads. Traditionally, natural products have been discovered by bioactivity-guided fractionation. The advent of genome sequencing technology has resulted in the introduction of an alternative approach towards novel natural product scaffolds: Genome mining. Genome mining is an in-silico natural product discovery strategy in which sequenced genomes are analyzed for the potential of the associated organism to produce natural products. Seemingly universal biosynthetic principles have been deciphered for most natural product classes that are used to detect natural product biosynthetic gene clusters using pathway-encoded conserved key enzymes, domains, or motifs as bait. Several generations of highly sophisticated tools have been developed for the biosynthetic rule-based identification of natural product gene clusters. Apart from these hard-coded algorithms, multiple tools that use machine learning-based approaches have been designed to complement the existing genome mining tool set and focus on natural product gene clusters that lack genes with conserved signature sequences. In this perspective, we take a closer look at state-of-the-art genome mining tools that are based on either hard-coded rules or machine learning algorithms, with an emphasis on the confidence of their predictions and potential to identify non-canonical natural product biosynthetic gene clusters. We highlight the genome mining pipelines' current strengths and limitations by contrasting their advantages and disadvantages. Moreover, we introduce two indirect biosynthetic gene cluster identification strategies that complement current workflows. The combination of all genome mining approaches will pave the way towards a more comprehensive understanding of the full biosynthetic repertoire encoded in microbial genome sequences.
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Affiliation(s)
- Friederike Biermann
- Institute for Molecular Bio Science, Goethe University Frankfurt, Max-von-Laue Str. 9, 60438 Frankfurt am Main, Germany,LOEWE Center for Translational Biodiversity Genomics (TBG), Senckenberganlage 25, 60325 Frankfurt am Main, Germany
| | - Sebastian L Wenski
- Institute for Molecular Bio Science, Goethe University Frankfurt, Max-von-Laue Str. 9, 60438 Frankfurt am Main, Germany,LOEWE Center for Translational Biodiversity Genomics (TBG), Senckenberganlage 25, 60325 Frankfurt am Main, Germany
| | - Eric J N Helfrich
- Institute for Molecular Bio Science, Goethe University Frankfurt, Max-von-Laue Str. 9, 60438 Frankfurt am Main, Germany,LOEWE Center for Translational Biodiversity Genomics (TBG), Senckenberganlage 25, 60325 Frankfurt am Main, Germany
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10
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Warhead assembly in a lethal pathogen. Nat Chem 2022; 14:848-850. [PMID: 35906403 DOI: 10.1038/s41557-022-01013-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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11
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Trottmann F, Ishida K, Ishida-Ito M, Kries H, Groll M, Hertweck C. Pathogenic bacteria remodel central metabolic enzyme to build a cyclopropanol warhead. Nat Chem 2022; 14:884-890. [PMID: 35906404 PMCID: PMC9359912 DOI: 10.1038/s41557-022-01005-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Accepted: 06/20/2022] [Indexed: 11/09/2022]
Abstract
Bacteria of the Burkholderia pseudomallei (BP) group pose a global health threat, causing the infectious diseases melioidosis, a common cause of pneumonia and sepsis, and glanders, a contagious zoonosis. A trait of BP bacteria is a conserved gene cluster coding for the biosynthesis of polyketides (malleicyprols) with a reactive cyclopropanol unit that is critical for virulence. Enzymes building this warhead represent ideal targets for antivirulence strategies but the biochemical basis of cyclopropanol formation is unknown. Here we describe the formation of the malleicyprol warhead. We show that BurG, an unusual NAD+-dependent member of the ketol-acid reductoisomerase family, constructs the strained cyclopropanol ring. Biochemical assays and a suite of eight crystal structures of native and mutated BurG with bound analogues and inhibitors provide snapshots of each step of the complex reaction mechanism, involving a concealed oxidoreduction and a C-S bond cleavage. Our findings illustrate a remarkable case of neofunctionalisation, where a biocatalyst from central metabolism has been evolutionarily repurposed for warhead production in pathogens.
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Affiliation(s)
- Felix Trottmann
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Product Research and Infection Biology - Hans Knöll Institute (Leibniz-HKI), Jena, Germany
| | - Keishi Ishida
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Product Research and Infection Biology - Hans Knöll Institute (Leibniz-HKI), Jena, Germany
| | - Mie Ishida-Ito
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Product Research and Infection Biology - Hans Knöll Institute (Leibniz-HKI), Jena, Germany
| | - Hajo Kries
- Junior Research Group Biosynthetic Design of Natural Products, Leibniz Institute for Natural Product Research and Infection Biology - Hans Knöll Institute (Leibniz-HKI), Jena, Germany
| | - Michael Groll
- Center for Protein Assemblies, Chemistry Department, Technical University Munich, Garching, Germany.
| | - Christian Hertweck
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Product Research and Infection Biology - Hans Knöll Institute (Leibniz-HKI), Jena, Germany. .,Faculty of Biological Sciences, Friedrich Schiller University Jena, Jena, Germany.
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12
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Berrios L. Examining the genomic features of human and plant-associated Burkholderia strains. Arch Microbiol 2022; 204:335. [PMID: 35587294 DOI: 10.1007/s00203-022-02953-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 04/01/2022] [Accepted: 05/02/2022] [Indexed: 11/28/2022]
Abstract
Humans and plants have evolved in the near omnipresence of a microbial milieu, and the factors that govern host-microbe interactions continue to require scientific exploration. To better understand if and to what degree patterns between microbial genomic features and host association (i.e., human and plant) exist, I analyzed the genomes of select Burkholderia strains-a bacterial genus comprised of both human and plant-associated strains-that were isolated from either humans or plants. To this end, I uncovered host-specific, genomic patterns related to metabolic pathway potentials in addition to convergent features that may be related to pathogenic overlap between hosts. Together, these findings detail the genomic associations of human and plant-associated Burkholderia strains and provide a framework for future investigations that seek to link host-host transmission potentials.
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Affiliation(s)
- Louis Berrios
- Department of Biology, Stanford University, Stanford, CA, 94305, USA.
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13
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Guidelines for metabolomics-guided transposon mutagenesis for microbial natural product discovery. Methods Enzymol 2022; 665:305-323. [PMID: 35379440 DOI: 10.1016/bs.mie.2021.11.020] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
There is a great discrepancy between the natural product output of cultured microorganisms and their bioinformatically predicted biosynthetic potential, such that most of the molecular diversity contained within microbial reservoirs has yet to be discovered. One of the primary reasons is insufficient expression of natural product biosynthetic gene clusters (BGCs) under standard laboratory conditions. Several methods have been developed to increase production from such "cryptic" BGCs. Among these, we recently implemented mass spectrometry-guided transposon mutagenesis, a forward genetic screen in which mutants that exhibit stimulated biosynthesis of cryptic metabolites, as read out by mass spectrometry, are selected from a transposon mutant library. Herein, we use Burkholderia gladioli as an example and provide guidelines for generating transposon mutant libraries, measuring metabolomic inventories through mass spectrometry, performing comparative metabolomics to prioritize cryptic natural products from the mutant library, and isolating and characterizing novel natural products elicited through mutagenesis. Application of this approach will be useful in both accessing novel natural products from cryptic BGCs and identifying genes involved in their global regulation.
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14
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Little R, Trottmann F, Preissler M, Hertweck C. An intramodular thioesterase domain catalyses chain release in the biosynthesis of a cytotoxic virulence factor. RSC Chem Biol 2022; 3:1121-1128. [PMID: 36128506 PMCID: PMC9428774 DOI: 10.1039/d2cb00121g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Accepted: 07/15/2022] [Indexed: 11/21/2022] Open
Abstract
The bimodular PKS-NRPS BurA has two unusual non-C-terminal thioesterase domains. We show that the intramodular TE-B is responsible for the hydrolytic release of gonyol, an intermediate for the biosynthesis of the virulence factor malleicyprol.
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Affiliation(s)
- Rory Little
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Product Research and Infection Biology HKI. Beutenbergstr. 11a, 07745 Jena, Germany
| | - Felix Trottmann
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Product Research and Infection Biology HKI. Beutenbergstr. 11a, 07745 Jena, Germany
| | - Miriam Preissler
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Product Research and Infection Biology HKI. Beutenbergstr. 11a, 07745 Jena, Germany
| | - Christian Hertweck
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Product Research and Infection Biology HKI. Beutenbergstr. 11a, 07745 Jena, Germany
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15
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Ma S, Mandalapu D, Wang S, Zhang Q. Biosynthesis of cyclopropane in natural products. Nat Prod Rep 2021; 39:926-945. [PMID: 34860231 DOI: 10.1039/d1np00065a] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Covering: 2012 to 2021Cyclopropane attracts wide interests in the fields of synthetic and pharmaceutical chemistry, and chemical biology because of its unique structural and chemical properties. This structural motif is widespread in natural products, and is usually essential for biological activities. Nature has evolved diverse strategies to access this structural motif, and increasing knowledge of the enzymes forming cyclopropane (i.e., cyclopropanases) has been revealed over the last two decades. Here, the scientific literature from the last two decades relating to cyclopropane biosynthesis is summarized, and the enzymatic cyclopropanations, according to reaction mechanism, which can be grouped into two major pathways according to whether the reaction involves an exogenous C1 unit from S-adenosylmethionine (SAM) or not, is discussed. The reactions can further be classified based on the key intermediates required prior to cyclopropane formation, which can be carbocations, carbanions, or carbon radicals. Besides the general biosynthetic pathways of the cyclopropane-containing natural products, particular emphasis is placed on the mechanism and engineering of the enzymes required for forming this unique structure motif.
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Affiliation(s)
- Suze Ma
- Department of Chemistry, Fudan University, Shanghai, 200433, China.
| | | | - Shu Wang
- Department of Chemistry, Fudan University, Shanghai, 200433, China.
| | - Qi Zhang
- Department of Chemistry, Fudan University, Shanghai, 200433, China.
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16
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Methodological tools to study species of the genus Burkholderia. Appl Microbiol Biotechnol 2021; 105:9019-9034. [PMID: 34755214 PMCID: PMC8578011 DOI: 10.1007/s00253-021-11667-3] [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: 09/13/2021] [Revised: 10/25/2021] [Accepted: 10/26/2021] [Indexed: 11/26/2022]
Abstract
Bacteria belonging to the Burkholderia genus are extremely versatile and diverse. They can be environmental isolates, opportunistic pathogens in cystic fibrosis, immunocompromised or chronic granulomatous disease patients, or cause disease in healthy people (e.g., Burkholderia pseudomallei) or animals (as in the case of Burkholderia mallei). Since the genus was separated from the Pseudomonas one in the 1990s, the methodological tools to study and characterize these bacteria are evolving fast. Here we reviewed the techniques used in the last few years to update the taxonomy of the genus, to study gene functions and regulations, to deepen the knowledge on the drug resistance which characterizes these bacteria, and to elucidate their mechanisms to establish infections. The availability of these tools significantly impacts the quality of research on Burkholderia and the choice of the most appropriated is fundamental for a precise characterization of the species of interest. Key points • Updated techniques to study the genus Burkholderia were reviewed. • Taxonomy, genomics, assays, and animal models were described. • A comprehensive overview on recent advances in Burkholderia studies was made.
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17
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Li A, Okada BK, Rosen PC, Seyedsayamdost MR. Piperacillin triggers virulence factor biosynthesis via the oxidative stress response in Burkholderia thailandensis. Proc Natl Acad Sci U S A 2021; 118:e2021483118. [PMID: 34172579 PMCID: PMC8256049 DOI: 10.1073/pnas.2021483118] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Natural products have been an important source of therapeutic agents and chemical tools. The recent realization that many natural product biosynthetic genes are silent or sparingly expressed during standard laboratory growth has prompted efforts to investigate their regulation and develop methods to induce their expression. Because it is difficult to intuit signals that induce a given biosynthetic locus, we recently implemented a forward chemical-genetic approach to identify such inducers. In the current work, we applied this approach to nine silent biosynthetic loci in the model bacterium Burkholderia thailandensis to systematically screen for elicitors from a library of Food and Drug Administration-approved drugs. We find that β-lactams, fluoroquinolones, antifungals, and, surprisingly, calcimimetics, phenothiazine antipsychotics, and polyaromatic antidepressants are the most effective global inducers of biosynthetic genes. Investigations into the mechanism of stimulation of the silent virulence factor malleicyprol by the β-lactam piperacillin allowed us to elucidate the underlying regulatory circuits. Low-dose piperacillin causes oxidative stress, thereby inducing redox-sensing transcriptional regulators, which activate malR, a pathway-specific positive regulator of the malleicyprol gene cluster. Malleicyprol is thus part of the OxyR and SoxR regulons in B. thailandensis, allowing the bacterium to initiate virulence in response to oxidative stress. Our work catalogs a diverse array of elicitors and a previously unknown regulatory input for secondary metabolism in B. thailandensis.
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Affiliation(s)
- Anran Li
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544
| | - Bethany K Okada
- Department of Chemistry, Princeton University, Princeton, NJ 08544
| | - Paul C Rosen
- Department of Chemistry, Princeton University, Princeton, NJ 08544
| | - Mohammad R Seyedsayamdost
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544;
- Department of Chemistry, Princeton University, Princeton, NJ 08544
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18
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Scherlach K, Hertweck C. Mining and unearthing hidden biosynthetic potential. Nat Commun 2021; 12:3864. [PMID: 34162873 PMCID: PMC8222398 DOI: 10.1038/s41467-021-24133-5] [Citation(s) in RCA: 107] [Impact Index Per Article: 35.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Accepted: 06/04/2021] [Indexed: 12/11/2022] Open
Abstract
Genetically encoded small molecules (secondary metabolites) play eminent roles in ecological interactions, as pathogenicity factors and as drug leads. Yet, these chemical mediators often evade detection, and the discovery of novel entities is hampered by low production and high rediscovery rates. These limitations may be addressed by genome mining for biosynthetic gene clusters, thereby unveiling cryptic metabolic potential. The development of sophisticated data mining methods and genetic and analytical tools has enabled the discovery of an impressive array of previously overlooked natural products. This review shows the newest developments in the field, highlighting compound discovery from unconventional sources and microbiomes. Natural products are an important source of bioactive compounds and have versatile applications in different fields, but their discovery is challenging. Here, the authors review the recent developments in genome mining for discovery of natural products, focusing on compounds from unconventional microorganisms and microbiomes.
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Affiliation(s)
- Kirstin Scherlach
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Product Research and Infection Biology, HKI, Jena, Germany
| | - Christian Hertweck
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Product Research and Infection Biology, HKI, Jena, Germany. .,Faculty of Biological Sciences, Friedrich Schiller University Jena, Jena, Germany.
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19
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Covington BC, Xu F, Seyedsayamdost MR. A Natural Product Chemist's Guide to Unlocking Silent Biosynthetic Gene Clusters. Annu Rev Biochem 2021; 90:763-788. [PMID: 33848426 PMCID: PMC9148385 DOI: 10.1146/annurev-biochem-081420-102432] [Citation(s) in RCA: 54] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Microbial natural products have provided an important source of therapeutic leads and motivated research and innovation in diverse scientific disciplines. In recent years, it has become evident that bacteria harbor a large, hidden reservoir of potential natural products in the form of silent or cryptic biosynthetic gene clusters (BGCs). These can be readily identified in microbial genome sequences but do not give rise to detectable levels of a natural product. Herein, we provide a useful organizational framework for the various methods that have been implemented for interrogating silent BGCs. We divide all available approaches into four categories. The first three are endogenous strategies that utilize the native host in conjunction with classical genetics, chemical genetics, or different culture modalities. The last category comprises expression of the entire BGC in a heterologous host. For each category, we describe the rationale, recent applications, and associated advantages and limitations.
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Affiliation(s)
- Brett C Covington
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, USA; ,
| | - Fei Xu
- Institute of Pharmaceutical Biotechnology and Department of Gastroenterology of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310058, China;
| | - Mohammad R Seyedsayamdost
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, USA; ,
- Department of Molecular Biology, Princeton University, New Jersey 08544, USA
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20
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Burkholderia thailandensis Methylated Hydroxyalkylquinolines: Biosynthesis and Antimicrobial Activity in Cocultures. Appl Environ Microbiol 2020; 86:AEM.01452-20. [PMID: 33008823 DOI: 10.1128/aem.01452-20] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Accepted: 09/15/2020] [Indexed: 02/04/2023] Open
Abstract
The bacterium Burkholderia thailandensis produces an arsenal of secondary metabolites that have diverse structures and roles in the ecology of this soil-dwelling bacterium. In coculture experiments, B. thailandensis strain E264 secretes an antimicrobial that nearly eliminates another soil bacterium, Bacillus subtilis strain 168. To identify the antimicrobial, we used a transposon mutagenesis approach. This screen identified antimicrobial-defective mutants with insertions in the hmqA, hmqC, and hmqF genes involved in biosynthesis of a family of 2-alkyl-4(1H)-quinolones called 4-hydroxy-3-methyl-2-alkenylquinolines (HMAQs), which are closely related to the Pseudomonas aeruginosa 4-hydroxy-2-alkylquinolines (HAQs). Insertions also occurred in the previously uncharacterized gene BTH_II1576 ("hmqL"). The results confirm that BTH_II1576 is involved in generating N-oxide derivatives of HMAQs (HMAQ-NOs). Synthetic HMAQ-NO is active against B. subtilis 168, showing ∼50-fold more activity than HMAQ. Both the methyl group and the length of the carbon side chain account for the high activity of HMAQ-NO. The results provide new information on the biosynthesis and activities of HMAQs and reveal new insight into how these molecules might be important for the ecology of B. thailandensis IMPORTANCE The soil bacterium Burkholderia thailandensis produces 2-alkyl-4(1H)-quinolones that are mostly methylated 4-hydroxyalkenylquinolines, a family of relatively unstudied metabolites similar to molecules also synthesized by Pseudomonas aeruginosa Several of the methylated 4-hydroxyalkenylquinolines have antimicrobial activity against other species. We show that Bacillus subtilis strain 168 is particularly susceptible to N-oxidated methylalkenylquinolines (HMAQ-NOs). We confirmed that HMAQ-NO biosynthesis requires the previously unstudied protein HmqL. These results provide new information about the biology of 2-alkyl-4(1H)-quinolones, particularly the methylated 4-hydroxyalkenylquinolines, which are unique to B. thailandensis This study also has importance for understanding B. thailandensis secondary metabolites and has implications for potential therapeutic development.
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21
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Williams PC, Wernke KM, Tirla A, Herzon SB. Employing chemical synthesis to study the structure and function of colibactin, a "dark matter" metabolite. Nat Prod Rep 2020; 37:1532-1548. [PMID: 33174565 PMCID: PMC7700718 DOI: 10.1039/d0np00072h] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Covering: 2015 to 2020 The field of natural products is dominated by a discovery paradigm that follows the sequence: isolation, structure elucidation, chemical synthesis, and then elucidation of mechanism of action and structure-activity relationships. Although this discovery paradigm has proven successful in the past, researchers have amassed enough evidence to conclude that the vast majority of nature's secondary metabolites - biosynthetic "dark matter" - cannot be identified and studied by this approach. Many biosynthetic gene clusters (BGCs) are expressed at low levels, or not at all, and in some instances a molecule's instability to fermentation or isolation prevents detection entirely. Here, we discuss an alternative approach to natural product identification that addresses these challenges by enlisting synthetic chemistry to prepare putative natural product fragments and structures as guided by biosynthetic insight. We demonstrate the utility of this approach through our structure elucidation of colibactin, an unisolable genotoxin produced by pathogenic bacteria in the human gut.
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Affiliation(s)
- Peyton C Williams
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, USA.
| | - Kevin M Wernke
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, USA.
| | - Alina Tirla
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, USA.
| | - Seth B Herzon
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, USA. and Department of Pharmacology, Yale School of Medicine, New Haven, Connecticut 06520, USA
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22
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Yoshimura A, Covington BC, Gallant É, Zhang C, Li A, Seyedsayamdost MR. Unlocking Cryptic Metabolites with Mass Spectrometry-Guided Transposon Mutant Selection. ACS Chem Biol 2020; 15:2766-2774. [PMID: 32808751 DOI: 10.1021/acschembio.0c00558] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The products of most secondary metabolite biosynthetic gene clusters (BGCs) have yet to be discovered, in part due to low expression levels in laboratory cultures. Reporter-guided mutant selection (RGMS) has recently been developed for this purpose: a mutant library is generated and screened, using genetic reporters to a chosen BGC, to select transcriptionally active mutants that then enable the characterization of the "cryptic" metabolite. The requirement for genetic reporters limits the approach to a single pathway within genetically tractable microorganisms. Herein, we utilize untargeted metabolomics in conjunction with transposon mutagenesis to provide a global read-out of secondary metabolism across large numbers of mutants. We employ self-organizing map analytics and imaging mass spectrometry to identify and characterize seven cryptic metabolites from mutant libraries of two different Burkholderia species. Applications of the methodologies reported can expand our understanding of the products and regulation of cryptic BGCs across phylogenetically diverse bacteria.
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Affiliation(s)
- Aya Yoshimura
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Brett C. Covington
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Étienne Gallant
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Chen Zhang
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Anran Li
- Department of Molecular Biology, Princeton University, Princeton, New Jersey 08544, United States
| | - Mohammad R. Seyedsayamdost
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
- Department of Molecular Biology, Princeton University, Princeton, New Jersey 08544, United States
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23
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Secondary metabolites from the Burkholderia pseudomallei complex: structure, ecology, and evolution. J Ind Microbiol Biotechnol 2020; 47:877-887. [PMID: 33052546 DOI: 10.1007/s10295-020-02317-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Accepted: 09/22/2020] [Indexed: 12/15/2022]
Abstract
Bacterial secondary metabolites play important roles in promoting survival, though few have been carefully studied in their natural context. Numerous gene clusters code for secondary metabolites in the genomes of members of the Bptm group, made up of three closely related species with distinctly different lifestyles: the opportunistic pathogen Burkholderia pseudomallei, the non-pathogenic saprophyte Burkholderia thailandensis, and the host-adapted pathogen Burkholderia mallei. Several biosynthetic gene clusters are conserved across two or all three species, and this provides an opportunity to understand how the corresponding secondary metabolites contribute to survival in different contexts in nature. In this review, we discuss three secondary metabolites from the Bptm group: bactobolin, malleilactone (and malleicyprol), and the 4-hydroxy-3-methyl-2-alkylquinolines, providing an overview of each of their biosynthetic pathways and insight into their potential ecological roles. Results of studies on these secondary metabolites provide a window into how secondary metabolites contribute to bacterial survival in different environments, from host infections to polymicrobial soil communities.
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24
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Mao D, Yoshimura A, Wang R, Seyedsayamdost MR. Reporter-Guided Transposon Mutant Selection for Activation of Silent Gene Clusters in Burkholderia thailandensis. Chembiochem 2020; 21:1826-1831. [PMID: 31984619 DOI: 10.1002/cbic.201900748] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Indexed: 01/01/2023]
Abstract
Most natural product biosynthetic gene clusters that can be observed bioinformatically are silent. This insight has prompted the development of several methodologies for inducing their expression. One of the more recent methods, termed reporter-guided mutant selection (RGMS), entails creation of a library of mutants that is then screened for the desired phenotype via reporter gene expression. Herein, we apply a similar approach to Burkholderia thailandensis and, using transposon mutagenesis, mutagenize three strains, each carrying a fluorescent reporter in the malleilactone (mal), capistruin (cap), or an unidentified ribosomal peptide (tomm) gene cluster. We show that even a small library of <500 mutants can be used to induce expression of each cluster. We also explore the mechanism of activation and find that inhibition of pyrimidine biosynthesis is linked to the induction of the mal cluster. Both a transposon insertion into pyrF as well as small-molecule-mediated inhibition of PyrF trigger malleilactone biosynthesis. Our results pave the way toward the broad application of RGMS and related approaches to Burkholderia spp.
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Affiliation(s)
- Dainan Mao
- Department of Chemistry, Princeton University, Princeton, NJ, 08544, USA
| | - Aya Yoshimura
- Department of Chemistry, Princeton University, Princeton, NJ, 08544, USA
| | - Rurun Wang
- Department of Chemistry, Princeton University, Princeton, NJ, 08544, USA
| | - Mohammad R Seyedsayamdost
- Department of Chemistry, Princeton University, Princeton, NJ, 08544, USA.,Department of Molecular Biology, Princeton University, Princeton, NJ, 08544, USA
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25
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Wu G, Yu G, Yu Y, Yang S, Duan Z, Wang W, Liu Y, Yu R, Li J, Zhu T, Gu Q, Li D. Chemoreactive-Inspired Discovery of Influenza A Virus Dual Inhibitor to Block Hemagglutinin-Mediated Adsorption and Membrane Fusion. J Med Chem 2020; 63:6924-6940. [PMID: 32520560 DOI: 10.1021/acs.jmedchem.0c00312] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Owing to the emergence of drug resistance and high morbidity and mortality, the need for novel anti-influenza A virus (IAV) drugs with divergent targets is highly sought after. Herein, we reveal the discovery of an anti-IAV agent as a dual inhibitor to block hemagglutinin-mediated adsorption and membrane fusion using a chemoreactive ortho-quinone methide (o-QM) equivalent. Based on the o-QM equivalent nonenzymatically multipotent behavior, we created a series of clavatol-derived pseudo-natural products and found that penindolone (PND), a new diclavatol indole adduct, exhibited potent and broad-spectrum anti-IAV activities with low risk of inducing drug resistance. Distinct from current anti-IAV drugs, PND possesses a novel scaffold and is the first IAV inhibitor targeting both HA1 and HA2 subunits of virus hemagglutinin to dually block the IAV adsorption and membrane fusion process. More importantly, intranasal and oral administration of PND can protect mice against IAV-induced death and weight loss, superior to the effects of the clinical drug oseltamivir. Thus, the use of chemoreactive intermediates could expand our understanding of chemical diversity and aid in the development of anti-IAV drugs with novel targets.
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Affiliation(s)
- Guangwei Wu
- Key Laboratory of Marine Drugs, Chinese Ministry of Education; School of Medicine and Pharmacy, Ocean University of China, 5 Yushan Road, Qingdao 26003, Shandong, P. R. China
| | - Guihong Yu
- Key Laboratory of Marine Drugs, Chinese Ministry of Education; School of Medicine and Pharmacy, Ocean University of China, 5 Yushan Road, Qingdao 26003, Shandong, P. R. China
| | - Yunjia Yu
- Key Laboratory of Marine Drugs, Chinese Ministry of Education; School of Medicine and Pharmacy, Ocean University of China, 5 Yushan Road, Qingdao 26003, Shandong, P. R. China
| | - Shuang Yang
- Key Laboratory of Marine Drugs, Chinese Ministry of Education; School of Medicine and Pharmacy, Ocean University of China, 5 Yushan Road, Qingdao 26003, Shandong, P. R. China
| | - Zhongwei Duan
- Key Laboratory of Marine Drugs, Chinese Ministry of Education; School of Medicine and Pharmacy, Ocean University of China, 5 Yushan Road, Qingdao 26003, Shandong, P. R. China
| | - Wei Wang
- Key Laboratory of Marine Drugs, Chinese Ministry of Education; School of Medicine and Pharmacy, Ocean University of China, 5 Yushan Road, Qingdao 26003, Shandong, P. R. China.,Laboratory for Marine Drugs and Bioproducts, Pilot National Laboratory for Marine Science and Technology, Qingdao 266200, People's Republic of China
| | - Yankai Liu
- Key Laboratory of Marine Drugs, Chinese Ministry of Education; School of Medicine and Pharmacy, Ocean University of China, 5 Yushan Road, Qingdao 26003, Shandong, P. R. China
| | - Rilei Yu
- Key Laboratory of Marine Drugs, Chinese Ministry of Education; School of Medicine and Pharmacy, Ocean University of China, 5 Yushan Road, Qingdao 26003, Shandong, P. R. China
| | - Jing Li
- Key Laboratory of Marine Drugs, Chinese Ministry of Education; School of Medicine and Pharmacy, Ocean University of China, 5 Yushan Road, Qingdao 26003, Shandong, P. R. China
| | - Tianjiao Zhu
- Key Laboratory of Marine Drugs, Chinese Ministry of Education; School of Medicine and Pharmacy, Ocean University of China, 5 Yushan Road, Qingdao 26003, Shandong, P. R. China
| | - Qianqun Gu
- Key Laboratory of Marine Drugs, Chinese Ministry of Education; School of Medicine and Pharmacy, Ocean University of China, 5 Yushan Road, Qingdao 26003, Shandong, P. R. China
| | - Dehai Li
- Key Laboratory of Marine Drugs, Chinese Ministry of Education; School of Medicine and Pharmacy, Ocean University of China, 5 Yushan Road, Qingdao 26003, Shandong, P. R. China.,Laboratory for Marine Drugs and Bioproducts, Pilot National Laboratory for Marine Science and Technology, Qingdao 266200, People's Republic of China
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26
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Trottmann F, Ishida K, Franke J, Stanišić A, Ishida‐Ito M, Kries H, Pohnert G, Hertweck C. Sulfonium Acids Loaded onto an Unusual Thiotemplate Assembly Line Construct the Cyclopropanol Warhead of a
Burkholderia
Virulence Factor. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202003958] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Felix Trottmann
- Department of Biomolecular Chemistry Leibniz Institute for Natural Product Research and Infection Biology (HKI) Beutenbergstrasse 11a 07745 Jena Germany
| | - Keishi Ishida
- Department of Biomolecular Chemistry Leibniz Institute for Natural Product Research and Infection Biology (HKI) Beutenbergstrasse 11a 07745 Jena Germany
| | - Jakob Franke
- Institute of Botany Leibniz University Hannover 30419 Hannover Germany
| | - Aleksa Stanišić
- Junior Research Group Biosynthetic Design of Natural Products Leibniz Institute for Natural Product Research and Infection Biology (HKI) Beutenbergstrasse 11a 07745 Jena Germany
| | - Mie Ishida‐Ito
- Department of Biomolecular Chemistry Leibniz Institute for Natural Product Research and Infection Biology (HKI) Beutenbergstrasse 11a 07745 Jena Germany
| | - Hajo Kries
- Junior Research Group Biosynthetic Design of Natural Products Leibniz Institute for Natural Product Research and Infection Biology (HKI) Beutenbergstrasse 11a 07745 Jena Germany
| | - Georg Pohnert
- Institute for Inorganic and Analytical Chemistry Friedrich Schiller University Jena 07743 Jena Germany
| | - Christian Hertweck
- Department of Biomolecular Chemistry Leibniz Institute for Natural Product Research and Infection Biology (HKI) Beutenbergstrasse 11a 07745 Jena Germany
- Natural Product Chemistry Faculty of Biological Sciences Friedrich Schiller University Jena 07743 Jena Germany
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Trottmann F, Ishida K, Franke J, Stanišić A, Ishida-Ito M, Kries H, Pohnert G, Hertweck C. Sulfonium Acids Loaded onto an Unusual Thiotemplate Assembly Line Construct the Cyclopropanol Warhead of a Burkholderia Virulence Factor. Angew Chem Int Ed Engl 2020; 59:13511-13515. [PMID: 32314848 PMCID: PMC7496086 DOI: 10.1002/anie.202003958] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Indexed: 12/13/2022]
Abstract
Pathogenic bacteria of the Burkholderia pseudomallei group cause severe infectious diseases such as glanders and melioidosis. Malleicyprols were identified as important bacterial virulence factors, yet the biosynthetic origin of their cyclopropanol warhead has remained enigmatic. By a combination of mutational analysis and metabolomics we found that sulfonium acids, dimethylsulfoniumpropionate (DMSP) and gonyol, known as osmolytes and as crucial components in the global organosulfur cycle, are key intermediates en route to the cyclopropanol unit. Functional genetics and in vitro analyses uncover a specialized pathway to DMSP involving a rare prokaryotic SET‐domain methyltransferase for a cryptic methylation, and show that DMSP is loaded onto the NRPS‐PKS hybrid assembly line by an adenylation domain dedicated to zwitterionic starter units. Then, the megasynthase transforms DMSP into gonyol, as demonstrated by heterologous pathway reconstitution in E. coli.
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Affiliation(s)
- Felix Trottmann
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Beutenbergstrasse 11a, 07745, Jena, Germany
| | - Keishi Ishida
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Beutenbergstrasse 11a, 07745, Jena, Germany
| | - Jakob Franke
- Institute of Botany, Leibniz University Hannover, 30419, Hannover, Germany
| | - Aleksa Stanišić
- Junior Research Group Biosynthetic Design of Natural Products, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Beutenbergstrasse 11a, 07745, Jena, Germany
| | - Mie Ishida-Ito
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Beutenbergstrasse 11a, 07745, Jena, Germany
| | - Hajo Kries
- Junior Research Group Biosynthetic Design of Natural Products, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Beutenbergstrasse 11a, 07745, Jena, Germany
| | - Georg Pohnert
- Institute for Inorganic and Analytical Chemistry, Friedrich Schiller University Jena, 07743, Jena, Germany
| | - Christian Hertweck
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Beutenbergstrasse 11a, 07745, Jena, Germany.,Natural Product Chemistry, Faculty of Biological Sciences, Friedrich Schiller University Jena, 07743, Jena, Germany
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Park JD, Moon K, Miller C, Rose J, Xu F, Ebmeier CC, Jacobsen JR, Mao D, Old WM, DeShazer D, Seyedsayamdost MR. Thailandenes, Cryptic Polyene Natural Products Isolated from Burkholderia thailandensis Using Phenotype-Guided Transposon Mutagenesis. ACS Chem Biol 2020; 15:1195-1203. [PMID: 31816232 DOI: 10.1021/acschembio.9b00883] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Burkholderia thailandensis has emerged as a model organism for investigating the production and regulation of diverse secondary metabolites. Most of the biosynthetic gene clusters encoded in B. thailandensis are silent, motivating the development of new methods for accessing their products. In the current work, we add to the canon of available approaches using phenotype-guided transposon mutagenesis to characterize a silent biosynthetic gene cluster. Because secondary metabolite biosynthesis is often associated with phenotypic changes, we carried out random transposon mutagenesis followed by phenotypic inspection of the resulting colonies. Several mutants exhibited intense pigmentation and enhanced expression of an iterative type I polyketide synthase cluster that we term org. Disruptions of orgA, orgB, and orgC abolished the biosynthesis of the diffusible pigment, thus linking it to the org operon. Isolation and structural elucidation by HR-MS and 1D/2D NMR spectroscopy revealed three novel, cryptic metabolites, thailandene A-C. Thailandenes are linear formylated or acidic polyenes containing a combination of cis and trans double bonds. Variants A and B exhibited potent antibiotic activity against Staphylococcus aureus and Saccharomyces cerevisiae but not against Escherichia coli. One of the transposon mutants that exhibited an enhanced expression of org contained an insertion upstream of a σ54-dependent transcription factor. Closer inspection of the org operon uncovered a σ54 promoter consensus sequence upstream of orgA, providing clues regarding its regulation. Our results showcase the utility of phenotype-guided transposon mutagenesis in uncovering cryptic metabolites encoded in bacterial genomes.
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Affiliation(s)
- Jong-Duk Park
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Kyuho Moon
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Cheryl Miller
- Molecular and Translational Science Division, U.S. Army Medical Research Institute of Infectious Diseases, Frederick, Maryland 21702, United States
| | - Jessica Rose
- Biotechnology Program, Hagerstown Community College, Hagerstown, Maryland 21742, United States
| | - Fei Xu
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Christopher C. Ebmeier
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder, Colorado 80309, United States
| | - Jeremy R. Jacobsen
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder, Colorado 80309, United States
| | - Dainan Mao
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - William M. Old
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder, Colorado 80309, United States
| | - David DeShazer
- Bacteriology Division, U.S. Army Medical Research Institute of Infectious Diseases, Frederick, Maryland 21702, United States
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Trottmann F, Franke J, Richter I, Ishida K, Cyrulies M, Dahse H, Regestein L, Hertweck C. Cyclopropanol Warhead in Malleicyprol Confers Virulence of Human- and Animal-Pathogenic Burkholderia Species. Angew Chem Int Ed Engl 2019; 58:14129-14133. [PMID: 31353766 PMCID: PMC6790655 DOI: 10.1002/anie.201907324] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Revised: 07/20/2019] [Indexed: 12/16/2022]
Abstract
Burkholderia species such as B. mallei and B. pseudomallei are bacterial pathogens causing fatal infections in humans and animals (glanders and melioidosis), yet knowledge on their virulence factors is limited. While pathogenic effects have been linked to a highly conserved gene locus (bur/mal) in the B. mallei group, the metabolite associated to the encoded polyketide synthase, burkholderic acid (syn. malleilactone), could not explain the observed phenotypes. By metabolic profiling and molecular network analyses of the model organism B. thailandensis, the primary products of the cryptic pathway were identified as unusual cyclopropanol-substituted polyketides. First, sulfomalleicyprols were identified as inactive precursors of burkholderic acid. Furthermore, a highly reactive upstream metabolite, malleicyprol, was discovered and obtained in two stabilized forms. Cell-based assays and a nematode infection model showed that the rare natural product confers cytotoxicity and virulence.
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Affiliation(s)
- Felix Trottmann
- Department of Biomolecular ChemistryLeibniz Institute for Natural Product Research and Infection Biology (HKI)Beutenbergstr. 11a07745JenaGermany
| | - Jakob Franke
- Institute of Organic Chemistry, BMWZLeibniz University Hannover30167HannoverGermany
| | - Ingrid Richter
- Department of Biomolecular ChemistryLeibniz Institute for Natural Product Research and Infection Biology (HKI)Beutenbergstr. 11a07745JenaGermany
| | - Keishi Ishida
- Department of Biomolecular ChemistryLeibniz Institute for Natural Product Research and Infection Biology (HKI)Beutenbergstr. 11a07745JenaGermany
| | - Michael Cyrulies
- Department Bio Pilot PlantLeibniz Institute for Natural Product Research and Infection Biology (HKI)07745JenaGermany
| | - Hans‐Martin Dahse
- Department Infection BiologyLeibniz Institute for Natural Product Research and Infection Biology (HKI)07745JenaGermany
| | - Lars Regestein
- Department Bio Pilot PlantLeibniz Institute for Natural Product Research and Infection Biology (HKI)07745JenaGermany
| | - Christian Hertweck
- Department of Biomolecular ChemistryLeibniz Institute for Natural Product Research and Infection Biology (HKI)Beutenbergstr. 11a07745JenaGermany
- Natural Product ChemistryFaculty of Biological SciencesFriedrich Schiller University Jena07743JenaGermany
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