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Skellam E, Rajendran S, Li L. Combinatorial biosynthesis for the engineering of novel fungal natural products. Commun Chem 2024; 7:89. [PMID: 38637654 PMCID: PMC11026467 DOI: 10.1038/s42004-024-01172-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2024] [Accepted: 04/08/2024] [Indexed: 04/20/2024] Open
Abstract
Natural products are small molecules synthesized by fungi, bacteria and plants, which historically have had a profound effect on human health and quality of life. These natural products have evolved over millions of years resulting in specific biological functions that may be of interest for pharmaceutical, agricultural, or nutraceutical use. Often natural products need to be structurally modified to make them suitable for specific applications. Combinatorial biosynthesis is a method to alter the composition of enzymes needed to synthesize a specific natural product resulting in structurally diversified molecules. In this review we discuss different approaches for combinatorial biosynthesis of natural products via engineering fungal enzymes and biosynthetic pathways. We highlight the biosynthetic knowledge gained from these studies and provide examples of new-to-nature bioactive molecules, including molecules synthesized using combinations of fungal and non-fungal enzymes.
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Affiliation(s)
- Elizabeth Skellam
- Department of Chemistry, University of North Texas, 1155 Union Circle, Denton, TX, 76203, USA.
- BioDiscovery Institute, University of North Texas, 1155 Union Circle, Denton, TX, 76203, USA.
- Department of Biological Sciences, University of North Texas, 1155 Union Circle, Denton, TX, 76203, USA.
| | - Sanjeevan Rajendran
- Department of Chemistry, University of North Texas, 1155 Union Circle, Denton, TX, 76203, USA
- BioDiscovery Institute, University of North Texas, 1155 Union Circle, Denton, TX, 76203, USA
| | - Lei Li
- Department of Chemistry, University of North Texas, 1155 Union Circle, Denton, TX, 76203, USA
- BioDiscovery Institute, University of North Texas, 1155 Union Circle, Denton, TX, 76203, USA
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2
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Li Y, Lin P, Lu X, Yan H, Wei H, Liu C, Liu X, Yang Y, Molnár I, Bai Z. Plasmid Copy Number Engineering Accelerates Fungal Polyketide Discovery upon Unnatural Polyketide Biosynthesis. ACS Synth Biol 2023; 12:2226-2235. [PMID: 37463503 DOI: 10.1021/acssynbio.3c00178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/20/2023]
Abstract
Saccharomyces cerevisiae has been extensively used as a convenient synthetic biology chassis to reconstitute fungal polyketide biosynthetic pathways. Despite progress in refactoring these pathways for expression and optimization of the yeast production host by metabolic engineering, product yields often remain unsatisfactory. Such problems are especially acute when synthetic biological production is used for bioprospecting via genome mining or when chimeric fungal polyketide synthases (PKSs) are employed to produce novel bioactive compounds. In this work, we demonstrate that empirically balancing the expression levels of the two collaborating PKS subunits that afford benzenediol lactone (BDL)-type fungal polyketides is a facile strategy to improve the product yields. This is accomplished by systematically and independently altering the copy numbers of the two plasmids that express these PKS subunits. We applied this plasmid copy number engineering strategy to two orphan PKSs from genome mining where the yields of the presumed BDL products in S. cerevisiae were far too low for product isolation. This optimization resulted in product yield improvements of up to 10-fold, allowing for the successful isolation and structure elucidation of new BDL analogues. Heterocombinations of these PKS subunits from genome mining with those from previously identified BDL pathways led to the combinatorial biosynthesis of several additional novel BDL-type polyketides.
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Affiliation(s)
- Ye Li
- National Engineering Research Center of Cereal Fermentation and Food Biomanufacturing, Jiangnan University, Wuxi 214122, China
| | - Pingxin Lin
- National Engineering Research Center of Cereal Fermentation and Food Biomanufacturing, Jiangnan University, Wuxi 214122, China
| | - Xuan Lu
- School of Life Science and Biotechnology, Dalian University, Dalian 116622, China
| | - Hao Yan
- National Engineering Research Center of Cereal Fermentation and Food Biomanufacturing, Jiangnan University, Wuxi 214122, China
| | - Huan Wei
- National Engineering Research Center of Cereal Fermentation and Food Biomanufacturing, Jiangnan University, Wuxi 214122, China
| | - Chunli Liu
- National Engineering Research Center of Cereal Fermentation and Food Biomanufacturing, Jiangnan University, Wuxi 214122, China
| | - Xiuxia Liu
- National Engineering Research Center of Cereal Fermentation and Food Biomanufacturing, Jiangnan University, Wuxi 214122, China
| | - Yankun Yang
- National Engineering Research Center of Cereal Fermentation and Food Biomanufacturing, Jiangnan University, Wuxi 214122, China
| | - István Molnár
- Southwest Center for Natural Products Research, University of Arizona, Tucson, Arizona 85706, United States
- VTT Technical Research Centre of Finland Ltd., Espoo 02044, Finland
| | - Zhonghu Bai
- National Engineering Research Center of Cereal Fermentation and Food Biomanufacturing, Jiangnan University, Wuxi 214122, China
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3
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Löhr NA, Rakhmanov M, Wurlitzer JM, Lackner G, Gressler M, Hoffmeister D. Basidiomycete non-reducing polyketide synthases function independently of SAT domains. Fungal Biol Biotechnol 2023; 10:17. [PMID: 37542286 PMCID: PMC10401856 DOI: 10.1186/s40694-023-00164-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Accepted: 07/16/2023] [Indexed: 08/06/2023] Open
Abstract
BACKGROUND Non-reducing polyketide synthases (NR-PKSs) account for a major share of natural product diversity produced by both Asco- and Basidiomycota. The present evolutionary diversification into eleven clades further underscores the relevance of these multi-domain enzymes. Following current knowledge, NR-PKSs initiate polyketide assembly by an N-terminal starter unit:acyl transferase (SAT) domain that catalyzes the transfer of an acetyl starter from the acetyl-CoA thioester onto the acyl carrier protein (ACP). RESULTS A comprehensive phylogenetic analysis of NR-PKSs established a twelfth clade from which three representatives, enzymes CrPKS1-3 of the webcap mushroom Cortinarius rufoolivaceus, were biochemically characterized. These basidiomycete synthases lack a SAT domain yet are fully functional hepta- and octaketide synthases in vivo. Three members of the other clade of basidiomycete NR-PKSs (clade VIII) were produced as SAT-domainless versions and analyzed in vivo and in vitro. They retained full activity, thus corroborating the notion that the SAT domain is dispensable for many basidiomycete NR-PKSs. For comparison, the ascomycete octaketide synthase atrochrysone carboxylic acid synthase (ACAS) was produced as a SAT-domainless enzyme as well, but turned out completely inactive. However, a literature survey revealed that some NR-PKSs of ascomycetes carry mutations within the catalytic motif of the SAT domain. In these cases, the role of the domain and the origin of the formal acetate unit remains open. CONCLUSIONS The role of SAT domains differs between asco- and basidiomycete NR-PKSs. For the latter, it is not part of the minimal set of NR-PKS domains and not required for function. This knowledge may help engineer compact NR-PKSs for more resource-efficient routes. From the genomic standpoint, seemingly incomplete or corrupted genes encoding SAT-domainless NR-PKSs should not automatically be dismissed as non-functional pseudogenes, but considered during genome analysis to decipher the potential arsenal of natural products of a given fungus.
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Affiliation(s)
- Nikolai A Löhr
- Institute of Pharmacy, Department Pharmaceutical Microbiology, Friedrich Schiller University Jena, Winzerlaer Strasse 2, 07745, Jena, Germany
- Department Pharmaceutical Microbiology, Leibniz Institute for Natural Product Research and Infection Biology - Hans Knöll Institute, Winzerlaer Strasse 2, 07745, Jena, Germany
| | - Malik Rakhmanov
- Institute of Pharmacy, Department Pharmaceutical Microbiology, Friedrich Schiller University Jena, Winzerlaer Strasse 2, 07745, Jena, Germany
- Department Pharmaceutical Microbiology, Leibniz Institute for Natural Product Research and Infection Biology - Hans Knöll Institute, Winzerlaer Strasse 2, 07745, Jena, Germany
| | - Jacob M Wurlitzer
- Institute of Pharmacy, Department Pharmaceutical Microbiology, Friedrich Schiller University Jena, Winzerlaer Strasse 2, 07745, Jena, Germany
- Department Pharmaceutical Microbiology, Leibniz Institute for Natural Product Research and Infection Biology - Hans Knöll Institute, Winzerlaer Strasse 2, 07745, Jena, Germany
| | - Gerald Lackner
- Synthetic Microbiology, Leibniz Institute for Natural Product Research and Infection Biology - Hans Knöll Institute, Winzerlaer Strasse 2, 07745, Jena, Germany
| | - Markus Gressler
- Institute of Pharmacy, Department Pharmaceutical Microbiology, Friedrich Schiller University Jena, Winzerlaer Strasse 2, 07745, Jena, Germany
- Department Pharmaceutical Microbiology, Leibniz Institute for Natural Product Research and Infection Biology - Hans Knöll Institute, Winzerlaer Strasse 2, 07745, Jena, Germany
| | - Dirk Hoffmeister
- Institute of Pharmacy, Department Pharmaceutical Microbiology, Friedrich Schiller University Jena, Winzerlaer Strasse 2, 07745, Jena, Germany.
- Department Pharmaceutical Microbiology, Leibniz Institute for Natural Product Research and Infection Biology - Hans Knöll Institute, Winzerlaer Strasse 2, 07745, Jena, Germany.
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Löhr NA, Urban MC, Eisen F, Platz L, Hüttel W, Gressler M, Müller M, Hoffmeister D. The Ketosynthase Domain Controls Chain Length in Mushroom Oligocyclic Polyketide Synthases. Chembiochem 2023; 24:e202200649. [PMID: 36507600 PMCID: PMC10108026 DOI: 10.1002/cbic.202200649] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Revised: 11/29/2022] [Accepted: 11/30/2022] [Indexed: 12/14/2022]
Abstract
The nonreducing iterative type I polyketide synthases (NR-PKSs) CoPKS1 and CoPKS4 of the webcap mushroom Cortinarius odorifer share 88 % identical amino acids. CoPKS1 almost exclusively produces a tricyclic octaketide product, atrochrysone carboxylic acid, whereas CoPKS4 shows simultaneous hepta- and octaketide synthase activity and also produces the bicyclic heptaketide 6-hydroxymusizin. To identify the region(s) controlling chain length, four chimeric enzyme variants were constructed and assayed for activity in Aspergillus niger as heterologous expression platform. We provide evidence that the β-ketoacyl synthase (KS) domain determines chain length in these mushroom NR-PKSs, even though their KS domains differ in only ten amino acids. A unique proline-rich linker connecting the acyl carrier protein with the thioesterase domain varies most between these two enzymes but is not involved in chain length control.
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Affiliation(s)
- Nikolai A Löhr
- Department Pharmaceutical Microbiology, Hans-Knöll-Institute, Friedrich-Schiller-Universität, Beutenbergstrasse 11a, 07745, Jena, Germany
| | - Maximilian C Urban
- Department Pharmaceutical Microbiology, Hans-Knöll-Institute, Friedrich-Schiller-Universität, Beutenbergstrasse 11a, 07745, Jena, Germany
| | - Frederic Eisen
- Institute of Pharmaceutical Sciences, Albert-Ludwigs-Universität Freiburg, Albertstrasse 25, 79104, Freiburg, Germany
| | - Lukas Platz
- Institute of Pharmaceutical Sciences, Albert-Ludwigs-Universität Freiburg, Albertstrasse 25, 79104, Freiburg, Germany
| | - Wolfgang Hüttel
- Institute of Pharmaceutical Sciences, Albert-Ludwigs-Universität Freiburg, Albertstrasse 25, 79104, Freiburg, Germany
| | - Markus Gressler
- Department Pharmaceutical Microbiology, Hans-Knöll-Institute, Friedrich-Schiller-Universität, Beutenbergstrasse 11a, 07745, Jena, Germany
| | - Michael Müller
- Institute of Pharmaceutical Sciences, Albert-Ludwigs-Universität Freiburg, Albertstrasse 25, 79104, Freiburg, Germany
| | - Dirk Hoffmeister
- Department Pharmaceutical Microbiology, Hans-Knöll-Institute, Friedrich-Schiller-Universität, Beutenbergstrasse 11a, 07745, Jena, Germany
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Li F, Lin Z, Torres JP, Hill EA, Li D, Townsend CA, Schmidt EW. Sea Urchin Polyketide Synthase SpPks1 Produces the Naphthalene Precursor to Echinoderm Pigments. J Am Chem Soc 2022; 144:9363-9371. [PMID: 35588530 DOI: 10.1021/jacs.2c01416] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Nearly every animal species on Earth contains a unique polyketide synthase (PKS) encoded in its genome, yet no animal-clade PKS has been biochemically characterized, and even the chemical products of these ubiquitous enzymes are known in only a few cases. The earliest animal genome-encoded PKS gene to be identified was SpPks1 from sea urchins. Previous genetic knockdown experiments implicated SpPks1 in synthesis of the sea urchin pigment echinochrome. Here, we express and purify SpPks1, performing biochemical experiments to demonstrate that the sea urchin protein is responsible for the synthesis of 2-acetyl-1,3,6,8-tetrahydroxynaphthalene (ATHN). Since ATHN is a plausible precursor of echinochromes, this result defines a biosynthetic pathway to the ubiquitous echinoderm pigments and rewrites the previous hypothesis for echinochrome biosynthesis. Truncation experiments showed that, unlike other type I iterative PKSs so far characterized, SpPks1 produces the naphthalene core using solely ketoacylsynthase (KS), acyltransferase, and acyl carrier protein domains, delineating a unique class of animal nonreducing aromatic PKSs (aPKSs). A series of amino acids in the KS domain define the family and are likely crucial in cyclization activity. Phylogenetic analyses indicate that SpPks1 and its homologs are widespread in echinoderms and their closest relatives, the acorn worms, reinforcing their fundamental importance to echinoderm biology. While the animal microbiome is known to produce aromatic polyketides, this work provides biochemical evidence that animals themselves also harbor ancient, convergent, dedicated pathways to carbocyclic aromatic polyketides. More fundamentally, biochemical analysis of SpPks1 begins to define the vast and unexplored biosynthetic space of the ubiquitous animal PKS family.
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Affiliation(s)
- Feng Li
- Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, P. R. China.,Department of Medicinal Chemistry, University of Utah, Salt Lake City, Utah 84112, United States
| | - Zhenjian Lin
- Department of Medicinal Chemistry, University of Utah, Salt Lake City, Utah 84112, United States
| | - Joshua P Torres
- Department of Medicinal Chemistry, University of Utah, Salt Lake City, Utah 84112, United States
| | - Eric A Hill
- Department of Chemistry, The Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Dehai Li
- Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, P. R. China
| | - Craig A Townsend
- Department of Chemistry, The Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Eric W Schmidt
- Department of Medicinal Chemistry, University of Utah, Salt Lake City, Utah 84112, United States
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6
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Adrover-Castellano ML, Schmidt JJ, Sherman DH. Biosynthetic Cyclization Catalysts for the Assembly of Peptide and Polyketide Natural Products. ChemCatChem 2021; 13:2095-2116. [PMID: 34335987 PMCID: PMC8320681 DOI: 10.1002/cctc.202001886] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Indexed: 12/13/2022]
Abstract
Many biologically active natural products are synthesized by nonribosomal peptide synthetases (NRPSs), polyketide synthases (PKSs) and their hybrids. These megasynthetases contain modules possessing distinct catalytic domains that allow for substrate initiation, chain extension, processing and termination. At the end of a module, a terminal domain, usually a thioesterase (TE), is responsible for catalyzing the release of the NRPS or PKS as a linear or cyclized product. In this review, we address the general cyclization mechanism of the TE domain, including oligomerization and the fungal C-C bond forming Claisen-like cyclases (CLCs). Additionally, we include examples of cyclization catalysts acting within or at the end of a module. Furthermore, condensation-like (CT) domains, terminal reductase (R) domains, reductase-like domains that catalyze Dieckmann condensation (RD), thioesterase-like Dieckmann cyclases, trans-acting TEs from the penicillin binding protein (PBP) enzyme family, product template (PT) domains and others will also be reviewed. The studies summarized here highlight the remarkable diversity of NRPS and PKS cyclization catalysts for the production of biologically relevant, complex cyclic natural products and related compounds.
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Affiliation(s)
| | - Jennifer J Schmidt
- Life Sciences Institute, University of Michigan, 210 Washtenaw Avenue, Ann Arbor, MI 48109-2216 (USA)
| | - David H Sherman
- Life Sciences Institute, University of Michigan, 210 Washtenaw Avenue, Ann Arbor, MI 48109-2216 (USA)
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Raps FC, Fäseke VC, Häussinger D, Sparr C. Catalyst‐Controlled Transannular Polyketide Cyclization Cascades: Selective Folding of Macrocyclic Polyketides. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202005733] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Felix C. Raps
- Department of Chemistry University of Basel St. Johanns-Ring 19 4056 Basel Switzerland
| | - Vincent C. Fäseke
- Department of Chemistry University of Basel St. Johanns-Ring 19 4056 Basel Switzerland
| | - Daniel Häussinger
- Department of Chemistry University of Basel St. Johanns-Ring 19 4056 Basel Switzerland
| | - Christof Sparr
- Department of Chemistry University of Basel St. Johanns-Ring 19 4056 Basel Switzerland
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Azizah M, Pripdeevech P, Thongkongkaew T, Mahidol C, Ruchirawat S, Kittakoop P. UHPLC-ESI-QTOF-MS/MS-Based Molecular Networking Guided Isolation and Dereplication of Antibacterial and Antifungal Constituents of Ventilago denticulata. Antibiotics (Basel) 2020; 9:antibiotics9090606. [PMID: 32942771 PMCID: PMC7558283 DOI: 10.3390/antibiotics9090606] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Revised: 09/11/2020] [Accepted: 09/12/2020] [Indexed: 12/22/2022] Open
Abstract
Ventilago denticulata is an herbal medicine for the treatment of wound infection; therefore this plant may rich in antibacterial agents. UHPLC-ESI-QTOF-MS/MS-Based molecular networking guided isolation and dereplication led to the identification of antibacterial and antifungal agents in V. denticulata. Nine antimicrobial agents in V. denticulata were isolated and characterized; they are divided into four groups including (I) flavonoid glycosides, rhamnazin 3-rhamninoside (7), catharticin or rhamnocitrin 3-rhamninoside (8), xanthorhamnin B or rhamnetin 3-rhamninoside (9), kaempferol 3-rhamninoside (10) and flavovilloside or quercetin 3-rhamninoside (11), (II) benzisochromanquinone, ventilatones B (12) and A (15), (III) a naphthopyrone ventilatone C (16) and (IV) a triterpene lupeol (13). Among the isolated compounds, ventilatone C (16) was a new compound. Moreover, kaempferol, chrysoeriol, isopimpinellin, rhamnetin, luteolin, emodin, rhamnocitrin, ventilagodenin A, rhamnazin and mukurozidiol, were tentatively identified as antimicrobial compounds in extracts of V. denticulata by a dereplication method. MS fragmentation of rhamnose-containing compounds gave an oxonium ion, C6H9O3+ at m/z 129, while that of galactose-containing glycosides provided the fragment ion at m/z 163 of C6H11O5+. These fragment ions may be used to confirm the presence of rhamnose or galactose in mass spectrometry-based analysis of natural glycosides or oligosaccharide attached to biomolecules, that is, glycoproteins.
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Affiliation(s)
- Muhaiminatul Azizah
- Chulabhorn Graduate Institute, Chemical Biology Program, Chulabhorn Royal Academy, Laksi, Bangkok 10210, Thailand; (M.A.); (T.T.); (C.M.); (S.R.)
| | - Patcharee Pripdeevech
- School of Science, Mae Fah Luang University, Muang, Chiang Rai 57100, Thailand;
- Center of Chemical Innovation for Sustainability (CIS), Mae Fah Luang University, Muang, Chiang Rai 57100, Thailand
| | - Tawatchai Thongkongkaew
- Chulabhorn Graduate Institute, Chemical Biology Program, Chulabhorn Royal Academy, Laksi, Bangkok 10210, Thailand; (M.A.); (T.T.); (C.M.); (S.R.)
| | - Chulabhorn Mahidol
- Chulabhorn Graduate Institute, Chemical Biology Program, Chulabhorn Royal Academy, Laksi, Bangkok 10210, Thailand; (M.A.); (T.T.); (C.M.); (S.R.)
- Chulabhorn Research Institute, Kamphaeng Phet 6 Road, Laksi, Bangkok 10210, Thailand
| | - Somsak Ruchirawat
- Chulabhorn Graduate Institute, Chemical Biology Program, Chulabhorn Royal Academy, Laksi, Bangkok 10210, Thailand; (M.A.); (T.T.); (C.M.); (S.R.)
- Chulabhorn Research Institute, Kamphaeng Phet 6 Road, Laksi, Bangkok 10210, Thailand
- Center of Excellence on Environmental Health and Toxicology (EHT), CHE, Ministry of Education, Bangkok 10210, Thailand
| | - Prasat Kittakoop
- Chulabhorn Graduate Institute, Chemical Biology Program, Chulabhorn Royal Academy, Laksi, Bangkok 10210, Thailand; (M.A.); (T.T.); (C.M.); (S.R.)
- Chulabhorn Research Institute, Kamphaeng Phet 6 Road, Laksi, Bangkok 10210, Thailand
- Center of Excellence on Environmental Health and Toxicology (EHT), CHE, Ministry of Education, Bangkok 10210, Thailand
- Correspondence: ; Tel.: +66-869755777
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9
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Raps FC, Fäseke VC, Häussinger D, Sparr C. Catalyst‐Controlled Transannular Polyketide Cyclization Cascades: Selective Folding of Macrocyclic Polyketides. Angew Chem Int Ed Engl 2020; 59:18390-18394. [DOI: 10.1002/anie.202005733] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Indexed: 11/09/2022]
Affiliation(s)
- Felix C. Raps
- Department of Chemistry University of Basel St. Johanns-Ring 19 4056 Basel Switzerland
| | - Vincent C. Fäseke
- Department of Chemistry University of Basel St. Johanns-Ring 19 4056 Basel Switzerland
| | - Daniel Häussinger
- Department of Chemistry University of Basel St. Johanns-Ring 19 4056 Basel Switzerland
| | - Christof Sparr
- Department of Chemistry University of Basel St. Johanns-Ring 19 4056 Basel Switzerland
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10
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Yang XL, Friedrich S, Yin S, Piech O, Williams K, Simpson TJ, Cox RJ. Molecular basis of methylation and chain-length programming in a fungal iterative highly reducing polyketide synthase. Chem Sci 2019; 10:8478-8489. [PMID: 31803427 PMCID: PMC6839510 DOI: 10.1039/c9sc03173a] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Accepted: 07/28/2019] [Indexed: 12/28/2022] Open
Abstract
Exchange of 32 different sub-fragments of the C-methyltransferase (C-MeT), pseudo-ketoreductase (ΨKR) and ketoreductase (KR) catalytic domains of the tenellin iterative Type I polyketide synthase non ribosomal peptide synthetase (PKS-NRPS) TENS by homologous fragments from the desmethylbassianin (DMBS) and militarinone (MILS) PKS-NRPS led to the creation of chimeric synthetases in which programming fidelity was altered, resulting in the production of mixtures of products with different methylation patterns and chain lengths. Swap of KR domain subfragments with the homologous fragments from the KR of the heptaketide militarinone synthetase resulted in the synthesis of penta, hexa and heptaketides. The results of these and previous experiments are rationalised by considering the existence of competition for acyl-carrier protein (ACP) bound substrates between different catalytic domains of the PKS. In particular, competition between the C-MeT and ketoreductase domains (KR) can account for methylation programming, and competition between the KR and the off-loading NRPS accounts for chain-length selectivity.
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Affiliation(s)
- Xiao-Long Yang
- Institute for Organic Chemistry , Leibniz University of Hannover , Schneiderberg 1B , 30167 , Hannover , Germany . .,BMWZ , Leibniz University of Hannover , Schneiderberg 38 , 30167 , Hannover , Germany
| | - Steffen Friedrich
- Institute for Organic Chemistry , Leibniz University of Hannover , Schneiderberg 1B , 30167 , Hannover , Germany . .,BMWZ , Leibniz University of Hannover , Schneiderberg 38 , 30167 , Hannover , Germany
| | - Sen Yin
- Institute for Organic Chemistry , Leibniz University of Hannover , Schneiderberg 1B , 30167 , Hannover , Germany . .,BMWZ , Leibniz University of Hannover , Schneiderberg 38 , 30167 , Hannover , Germany
| | - Oliver Piech
- Institute for Organic Chemistry , Leibniz University of Hannover , Schneiderberg 1B , 30167 , Hannover , Germany . .,BMWZ , Leibniz University of Hannover , Schneiderberg 38 , 30167 , Hannover , Germany
| | - Katherine Williams
- Institute for Organic Chemistry , Leibniz University of Hannover , Schneiderberg 1B , 30167 , Hannover , Germany . .,BMWZ , Leibniz University of Hannover , Schneiderberg 38 , 30167 , Hannover , Germany.,School of Chemistry , University of Bristol , Cantock's Close , Bristol , BS8 1TS , UK
| | - Thomas J Simpson
- School of Chemistry , University of Bristol , Cantock's Close , Bristol , BS8 1TS , UK
| | - Russell J Cox
- Institute for Organic Chemistry , Leibniz University of Hannover , Schneiderberg 1B , 30167 , Hannover , Germany . .,BMWZ , Leibniz University of Hannover , Schneiderberg 38 , 30167 , Hannover , Germany
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11
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Storm PA, Pal P, Huitt-Roehl CR, Townsend CA. Exploring Fungal Polyketide C-Methylation through Combinatorial Domain Swaps. ACS Chem Biol 2018; 13:3043-3048. [PMID: 30350943 DOI: 10.1021/acschembio.8b00429] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Polyketide C-methylation occurs during a programmed sequence of dozens of reactions carried out by multidomain polyketide synthases (PKSs). Fungal PKSs perform these reactions iteratively, where a domain may be exposed to and act upon multiple enzyme-tethered intermediates during biosynthesis. We surveyed a collection of C-methyltransferase (CMeT) domains from nonreducing fungal PKSs to gain insight into how different methylation patterns are installed. Our in vitro results show that control of methylation resides primarily with the CMeT, and CMeTs can intercept and methylate intermediates from noncognate nonreducing PKS domains. Furthermore, the methylation pattern is likely imposed by a competition between methylation or ketosynthase-catalyzed extension for each intermediate. Understanding site-specific polyketide C-methylation may facilitate targeted C-C bond formation in engineered biosynthetic pathways.
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Affiliation(s)
- Philip A. Storm
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Paramita Pal
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Callie R. Huitt-Roehl
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Craig A. Townsend
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
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12
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Abstract
Covering: up to mid of 2018 Type I fatty acid synthases (FASs) are giant multienzymes catalyzing all steps of the biosynthesis of fatty acids from acetyl- and malonyl-CoA by iterative precursor extension. Two strikingly different architectures of FAS evolved in yeast (as well as in other fungi and some bacteria) and metazoans. Yeast-type FAS (yFAS) assembles into a barrel-shaped structure of more than 2 MDa molecular weight. Catalytic domains of yFAS are embedded in an extensive scaffolding matrix and arranged around two enclosed reaction chambers. Metazoan FAS (mFAS) is a 540 kDa X-shaped dimer, with lateral reaction clefts, minimal scaffolding and pronounced conformational variability. All naturally occurring yFAS are strictly specialized for the production of saturated fatty acids. The yFAS architecture is not used for the biosynthesis of any other secondary metabolite. On the contrary, mFAS is related at the domain organization level to major classes of polyketide synthases (PKSs). PKSs produce a variety of complex and potent secondary metabolites; they either act iteratively (iPKS), or are linked via directed substrate transfer into modular assembly lines (modPKSs). Here, we review the architectures of yFAS, mFAS, and iPKSs. We rationalize the evolution of the yFAS assembly, and provide examples for re-engineering of yFAS. Recent studies have provided novel insights into the organization of iPKS. A hybrid crystallographic model of a mycocerosic acid synthase-like Pks5 yielded a comprehensive visualization of the organization and dynamics of fully-reducing iPKS. Deconstruction experiments, structural and functional studies of specialized enzymatic domains, such as the product template (PT) and the starter-unit acyltransferase (SAT) domain have revealed functional principles of non-reducing iterative PKS (NR-PKSs). Most recently, a six-domain loading region of an NR-PKS has been visualized at high-resolution together with cryo-EM studies of a trapped loading intermediate. Altogether, these data reveal the related, yet divergent architectures of mFAS, iPKS and also modPKSs. The new insights highlight extensive dynamics, and conformational coupling as key features of mFAS and iPKS and are an important step towards collection of a comprehensive series of snapshots of PKS action.
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Affiliation(s)
- Dominik A Herbst
- Department Biozentrum, University of Basel, Klingelbergstrasse 50/70, 4056 Basel, Switzerland.
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13
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Chevrette MG, Currie CR. Emerging evolutionary paradigms in antibiotic discovery. J Ind Microbiol Biotechnol 2018; 46:257-271. [PMID: 30269177 DOI: 10.1007/s10295-018-2085-6] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Accepted: 09/25/2018] [Indexed: 12/11/2022]
Abstract
Antibiotics revolutionized medicine and remain its cornerstone. Despite their global importance and the continuous threat of resistant pathogens, few antibiotics have been discovered in recent years. Natural products, especially the secondary metabolites of Actinobacteria, have been the traditional discovery source of antibiotics. In nature, the chemistry of antibiotic natural products is shaped by the unique evolution and ecology of their producing organisms, yet these influences remain largely unknown. Here, we highlight the ecology of antibiotics employed by microbes in defensive symbioses and review the evolutionary processes underlying the chemical diversity and activity of microbe-derived antibiotics, including the dynamics of vertical and lateral transmission of biosynthetic pathways and the evolution of efficacy, targeting specificity, and toxicity. We argue that a deeper understanding of the ecology and evolution of microbial interactions and the metabolites that mediate them will allow for an alternative, rational approach to discover new antibiotics.
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Affiliation(s)
- Marc G Chevrette
- Department of Genetics, University of Wisconsin-Madison, Madison, WI, USA.,Department of Bacteriology, University of Wisconsin-Madison, Madison, WI, USA
| | - Cameron R Currie
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI, USA.
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14
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Herbst DA, Huitt-Roehl CR, Jakob RP, Kravetz JM, Storm PA, Alley JR, Townsend CA, Maier T. The structural organization of substrate loading in iterative polyketide synthases. Nat Chem Biol 2018; 14:474-479. [PMID: 29610486 DOI: 10.1038/s41589-018-0026-3] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Accepted: 02/07/2018] [Indexed: 11/09/2022]
Abstract
Polyketide synthases (PKSs) are microbial multienzymes for the biosynthesis of biologically potent secondary metabolites. Polyketide production is initiated by the loading of a starter unit onto an integral acyl carrier protein (ACP) and its subsequent transfer to the ketosynthase (KS). Initial substrate loading is achieved either by multidomain loading modules or by the integration of designated loading domains, such as starter unit acyltransferases (SAT), whose structural integration into PKS remains unresolved. A crystal structure of the loading/condensing region of the nonreducing PKS CTB1 demonstrates the ordered insertion of a pseudodimeric SAT into the condensing region, which is aided by the SAT-KS linker. Cryo-electron microscopy of the post-loading state trapped by mechanism-based crosslinking of ACP to KS reveals asymmetry across the CTB1 loading/-condensing region, in accord with preferential 1:2 binding stoichiometry. These results are critical for re-engineering the loading step in polyketide biosynthesis and support functional relevance of asymmetric conformations of PKSs.
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Affiliation(s)
- Dominik A Herbst
- Department of Biozentrum, University of Basel, Basel, Switzerland
| | | | - Roman P Jakob
- Department of Biozentrum, University of Basel, Basel, Switzerland
| | - Jacob M Kravetz
- Department of Chemistry, Johns Hopkins University, Baltimore, MD, USA
| | - Philip A Storm
- Department of Chemistry, Johns Hopkins University, Baltimore, MD, USA
| | - Jamie R Alley
- Department of Chemistry, Johns Hopkins University, Baltimore, MD, USA
| | - Craig A Townsend
- Department of Chemistry, Johns Hopkins University, Baltimore, MD, USA
| | - Timm Maier
- Department of Biozentrum, University of Basel, Basel, Switzerland.
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15
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Storm PA, Herbst DA, Maier T, Townsend CA. Functional and Structural Analysis of Programmed C-Methylation in the Biosynthesis of the Fungal Polyketide Citrinin. Cell Chem Biol 2017; 24:316-325. [PMID: 28238725 DOI: 10.1016/j.chembiol.2017.01.008] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2016] [Revised: 11/30/2016] [Accepted: 01/30/2017] [Indexed: 01/09/2023]
Abstract
Fungal polyketide synthases (PKSs) are large, multidomain enzymes that biosynthesize a wide range of natural products. A hallmark of these megasynthases is the iterative use of catalytic domains to extend and modify a series of enzyme-bound intermediates. A subset of these iterative PKSs (iPKSs) contains a C-methyltransferase (CMeT) domain that adds one or more S-adenosylmethionine (SAM)-derived methyl groups to the carbon framework. Neither the basis by which only specific positions on the growing intermediate are methylated ("programming") nor the mechanism of methylation are well understood. Domain dissection and reconstitution of PksCT, the fungal non-reducing PKS (NR-PKS) responsible for the first isolable intermediate in citrinin biosynthesis, demonstrates the role of CMeT-catalyzed methylation in precursor elongation and pentaketide formation. The crystal structure of the S-adenosyl-homocysteine (SAH) coproduct-bound PksCT CMeT domain reveals a two-subdomain organization with a novel N-terminal subdomain characteristic of PKS CMeT domains and provides insights into co-factor and ligand recognition.
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Affiliation(s)
- Philip A Storm
- Department of Chemistry, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Dominik A Herbst
- Department Biozentrum, University of Basel, Klingelbergstrasse 50/70, 4056 Basel, Switzerland
| | - Timm Maier
- Department Biozentrum, University of Basel, Klingelbergstrasse 50/70, 4056 Basel, Switzerland
| | - Craig A Townsend
- Department of Chemistry, Johns Hopkins University, Baltimore, MD 21218, USA.
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Thomas R. Examination of Potential Exceptions to the F and S Biosynthetic Classification of Fused-Ring Aromatic Polyketides. Chembiochem 2016; 17:2208-2215. [PMID: 27753463 DOI: 10.1002/cbic.201600315] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Indexed: 01/20/2023]
Abstract
The reported acetate-derived labelling of the fungal naphthalene γ-pyrone fonsecin, two streptomycete dodecaketide αpyrones TW93f and TW93g, and the streptomycete phenanthraquinones piloquinone, murayaquinone and haloquinone appear to be exceptions to the generalisation that fungi and streptomycetes produce fused-ring aromatic polyketides by different modes of cyclisation. A review of their 1) originally assigned formulae, 2) [13 C2 ]acetate-derived labelling patterns, and 3) modes of cyclisation leads to the recognition of feasible alternative chemical structures or biosynthetic pathways, which are in accord with the originally proposed classification system.
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Marine Fungi as Producers of Benzocoumarins, a New Class of Inhibitors of Glycogen-Synthase-Kinase 3β. Mar Drugs 2016; 14:md14110200. [PMID: 27801816 PMCID: PMC5128743 DOI: 10.3390/md14110200] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Revised: 10/17/2016] [Accepted: 10/22/2016] [Indexed: 11/16/2022] Open
Abstract
The glycogen-synthase-kinase 3 (GSK-3) is an important target in drug discovery. This enzyme is involved in the signaling pathways of type 2 diabetes, neurological disorders, cancer, and other diseases. Therefore, inhibitors of GSK-3 are promising drug candidates for the treatment of a broad range of diseases. Here we report pannorin (1), alternariol (2), and alternariol-9-methylether (3) to be promising inhibitors of the isoform GSK-3β showing sub-μM IC50 values. The in vitro inhibition is in the range of the known highly active GSK-3β inhibitor TDZD-8. Compounds 1-3 have a highly oxygenated benzocoumarin core structure in common, which suggests that this may be a new structural feature for efficient GSK-3β inhibition.
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Gao SS, Duan A, Xu W, Yu P, Hang L, Houk KN, Tang Y. Phenalenone Polyketide Cyclization Catalyzed by Fungal Polyketide Synthase and Flavin-Dependent Monooxygenase. J Am Chem Soc 2016; 138:4249-59. [PMID: 26978228 PMCID: PMC4988900 DOI: 10.1021/jacs.6b01528] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Phenalenones are polyketide natural products that display diverse structures and biological activities. The core of phenalenones is a peri-fused tricyclic ring system cyclized from a linear polyketide precursor via an unresolved mechanism. Toward understanding the unusual cyclization steps, the phn biosynthetic gene cluster responsible for herqueinone biosynthesis was identified from the genome of Penicillium herquei. A nonreducing polyketide synthase (NR-PKS) PhnA was shown to synthesize the heptaketide backbone and cyclize it into the angular, hemiketal-containing naphtho-γ-pyrone prephenalenone. The product template (PT) domain of PhnA catalyzes only the C4-C9 aldol condensation, which is unprecedented among known PT domains. The transformation of prephenalenone to phenalenone requires an FAD-dependent monooxygenase (FMO) PhnB, which catalyzes the C2 aromatic hydroxylation of prephenalenone and ring opening of the γ-pyrone ring simultaneously. Density functional theory calculations provide insights into why the hydroxylated intermediate undergoes an aldol-like phenoxide-ketone cyclization to yield the phenalenone core. This study therefore unveiled new routes and biocatalysts for polyketide cyclization.
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Affiliation(s)
- Shu-Shan Gao
- Department of Chemical and Biomolecular Engineering, University of California, Los Angeles, California 90095, United States
| | - Abing Duan
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, United States
| | - Wei Xu
- Department of Chemical and Biomolecular Engineering, University of California, Los Angeles, California 90095, United States
| | - Peiyuan Yu
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, United States
| | - Leibniz Hang
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, United States
| | - K. N. Houk
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, United States
| | - Yi Tang
- Department of Chemical and Biomolecular Engineering, University of California, Los Angeles, California 90095, United States
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, United States
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19
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Parascandolo JS, Havemann J, Potter HK, Huang F, Riva E, Connolly J, Wilkening I, Song L, Leadlay PF, Tosin M. Insights into 6-Methylsalicylic Acid Bio-assembly by Using Chemical Probes. ANGEWANDTE CHEMIE (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2016; 128:3524-3528. [PMID: 27478274 PMCID: PMC4950124 DOI: 10.1002/ange.201509038] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/26/2015] [Revised: 11/19/2015] [Indexed: 01/19/2023]
Abstract
Chemical probes capable of reacting with KS (ketosynthase)-bound biosynthetic intermediates were utilized for the investigation of the model type I iterative polyketide synthase 6-methylsalicylic acid synthase (6-MSAS) in vivo and in vitro. From the fermentation of fungal and bacterial 6-MSAS hosts in the presence of chain termination probes, a full range of biosynthetic intermediates was isolated and characterized for the first time. Meanwhile, in vitro studies of recombinant 6-MSA synthases with both nonhydrolyzable and hydrolyzable substrate mimics have provided additional insights into substrate recognition, providing the basis for further exploration of the enzyme catalytic activities.
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Affiliation(s)
| | - Judith Havemann
- Department of ChemistryUniversity of WarwickLibrary RoadCoventryCV4 7ALUK
| | - Helen K. Potter
- Department of ChemistryUniversity of CambridgeLensfield RoadCambridgeCB2 1EWUK
| | - Fanglu Huang
- Department of ChemistryUniversity of CambridgeLensfield RoadCambridgeCB2 1EWUK
- Department of BiochemistryUniversity of Cambridge80 Tennis Court RoadCambridgeCB2 1GAUK
| | - Elena Riva
- Department of ChemistryUniversity of WarwickLibrary RoadCoventryCV4 7ALUK
| | - Jack Connolly
- Department of ChemistryUniversity of WarwickLibrary RoadCoventryCV4 7ALUK
- School of BiosciencesThe University of BirminghamBirminghamB15 2TTUK
| | - Ina Wilkening
- Department of ChemistryUniversity of WarwickLibrary RoadCoventryCV4 7ALUK
| | - Lijiang Song
- Department of ChemistryUniversity of WarwickLibrary RoadCoventryCV4 7ALUK
| | - Peter F. Leadlay
- Department of BiochemistryUniversity of Cambridge80 Tennis Court RoadCambridgeCB2 1GAUK
| | - Manuela Tosin
- Department of ChemistryUniversity of WarwickLibrary RoadCoventryCV4 7ALUK
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20
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Parascandolo JS, Havemann J, Potter HK, Huang F, Riva E, Connolly J, Wilkening I, Song L, Leadlay PF, Tosin M. Insights into 6-Methylsalicylic Acid Bio-assembly by Using Chemical Probes. Angew Chem Int Ed Engl 2016; 55:3463-7. [PMID: 26833898 PMCID: PMC4797705 DOI: 10.1002/anie.201509038] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2015] [Revised: 11/19/2015] [Indexed: 01/21/2023]
Abstract
Chemical probes capable of reacting with KS (ketosynthase)-bound biosynthetic intermediates were utilized for the investigation of the model type I iterative polyketide synthase 6-methylsalicylic acid synthase (6-MSAS) in vivo and in vitro. From the fermentation of fungal and bacterial 6-MSAS hosts in the presence of chain termination probes, a full range of biosynthetic intermediates was isolated and characterized for the first time. Meanwhile, in vitro studies of recombinant 6-MSA synthases with both nonhydrolyzable and hydrolyzable substrate mimics have provided additional insights into substrate recognition, providing the basis for further exploration of the enzyme catalytic activities.
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Affiliation(s)
- James S Parascandolo
- Department of Chemistry, University of Warwick, Library Road, Coventry, CV4 7AL, UK
| | - Judith Havemann
- Department of Chemistry, University of Warwick, Library Road, Coventry, CV4 7AL, UK
| | - Helen K Potter
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK
| | - Fanglu Huang
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge, CB2 1GA, UK
| | - Elena Riva
- Department of Chemistry, University of Warwick, Library Road, Coventry, CV4 7AL, UK
| | - Jack Connolly
- Department of Chemistry, University of Warwick, Library Road, Coventry, CV4 7AL, UK
- School of Biosciences, The University of Birmingham, Birmingham, B15 2TT, UK
| | - Ina Wilkening
- Department of Chemistry, University of Warwick, Library Road, Coventry, CV4 7AL, UK
| | - Lijiang Song
- Department of Chemistry, University of Warwick, Library Road, Coventry, CV4 7AL, UK
| | - Peter F Leadlay
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge, CB2 1GA, UK
| | - Manuela Tosin
- Department of Chemistry, University of Warwick, Library Road, Coventry, CV4 7AL, UK.
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21
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Rational biosynthetic approaches for the production of new-to-nature compounds in fungi. Fungal Genet Biol 2016; 89:89-101. [PMID: 26872866 DOI: 10.1016/j.fgb.2016.02.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Revised: 02/04/2016] [Accepted: 02/04/2016] [Indexed: 01/06/2023]
Abstract
Filamentous fungi have the ability to produce a wide range of secondary metabolites some of which are potent toxins whereas others are exploited as food additives or drugs. Fungal natural products still play an important role in the discovery of new chemical entities for potential use as pharmaceuticals. However, in most cases they cannot be directly used as drugs due to toxic side effects or suboptimal pharmacokinetics. To improve drug-like properties, including bioactivity and stability or to produce better precursors for semi-synthetic routes, one needs to generate non-natural derivatives from known fungal secondary metabolites. In this minireview, we describe past and recent biosynthetic approaches for the diversification of fungal natural products, covering examples from precursor-directed biosynthesis, mutasynthesis, metabolic engineering and biocombinatorial synthesis. To illustrate the current state-of-the-art, challenges and pitfalls, we lay particular emphasis on the class of fungal cyclodepsipeptides which have been studied longtime for product diversification and which are of pharmaceutical relevance as drugs.
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Kaur A, Raja HA, Deep G, Agarwal R, Oberlies NH. Pannorin B, a new naphthopyrone from an endophytic fungal isolate of Penicillium sp. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2016; 54:164-7. [PMID: 26365944 PMCID: PMC10797558 DOI: 10.1002/mrc.4324] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2015] [Revised: 07/22/2015] [Accepted: 07/29/2015] [Indexed: 06/05/2023]
Affiliation(s)
- Amninder Kaur
- Department of Chemistry and Biochemistry, University of North Carolina at Greensboro, P.O. Box 26170, Greensboro, North Carolina 27402, United States
| | - Huzefa A. Raja
- Department of Chemistry and Biochemistry, University of North Carolina at Greensboro, P.O. Box 26170, Greensboro, North Carolina 27402, United States
| | - Gagan Deep
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Denver, Aurora, CO 80045, United States
| | - Rajesh Agarwal
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Denver, Aurora, CO 80045, United States
| | - Nicholas H. Oberlies
- Department of Chemistry and Biochemistry, University of North Carolina at Greensboro, P.O. Box 26170, Greensboro, North Carolina 27402, United States
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23
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Mattern DJ, Valiante V, Unkles SE, Brakhage AA. Synthetic biology of fungal natural products. Front Microbiol 2015; 6:775. [PMID: 26284053 PMCID: PMC4519758 DOI: 10.3389/fmicb.2015.00775] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Accepted: 07/14/2015] [Indexed: 01/08/2023] Open
Abstract
Synthetic biology is an ever-expanding field in science, also encompassing the research area of fungal natural product (NP) discovery and production. Until now, different aspects of synthetic biology have been covered in fungal NP studies from the manipulation of different regulatory elements and heterologous expression of biosynthetic pathways to the engineering of different multidomain biosynthetic enzymes such as polyketide synthases or non-ribosomal peptide synthetases. The following review will cover some of the exemplary studies of synthetic biology in filamentous fungi showing the capacity of these eukaryotes to be used as model organisms in the field. From the vast array of different NPs produced to the ease for genetic manipulation, filamentous fungi have proven to be an invaluable source for the further development of synthetic biology tools.
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Affiliation(s)
- Derek J Mattern
- Department of Molecular and Applied Microbiology, Leibniz Institute for Natural Product Research and Infection Biology - Hans Knöll Institute , Jena, Germany ; Institute for Microbiology, Friedrich Schiller University , Jena, Germany
| | - Vito Valiante
- Leibniz Junior Research Group "Biobricks of Microbial Natural Product Syntheses" , Jena, Germany
| | - Shiela E Unkles
- School of Biology, Biomedical Sciences Research Complex, University of St Andrews , St Andrews, UK
| | - Axel A Brakhage
- Department of Molecular and Applied Microbiology, Leibniz Institute for Natural Product Research and Infection Biology - Hans Knöll Institute , Jena, Germany ; Institute for Microbiology, Friedrich Schiller University , Jena, Germany
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Huitt-Roehl CR, Hill EA, Adams MM, Vagstad AL, Li JW, Townsend CA. Starter unit flexibility for engineered product synthesis by the nonreducing polyketide synthase PksA. ACS Chem Biol 2015; 10:1443-9. [PMID: 25714897 DOI: 10.1021/acschembio.5b00005] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Nonreducing polyketide synthases (NR-PKSs) are unique among PKSs in their domain structure, notably including a starter unit:acyl-carrier protein (ACP) transacylase (SAT) domain that selects an acyl group as the primer for biosynthesis, most commonly acetyl-CoA from central metabolism. This clan of mega-enzymes resembles fatty acid synthases (FASs) by sharing both their central chain elongation steps and their capacity for iterative catalysis. In this mode of synthesis, catalytic domains involved in chain extension exhibit substrate plasticity to accommodate growing chains as small as two carbons to 20 or more. PksA is the NR-PKS central to the biosynthesis of the mycotoxin aflatoxin B1 whose SAT domain accepts an unusual hexanoyl starter from a dedicated yeast-like FAS. Explored in this paper is the ability of PksA to utilize a selection of potential starter units as substrates to initiate and sustain extension and cyclization to on-target, programmed polyketide synthesis. Most of these starter units were successfully accepted and properly processed by PksA to achieve biosynthesis of the predicted naphthopyrone product. Analysis of the on-target and derailment products revealed trends of tolerance by individual PksA domains to alternative starter units. In addition, natural and un-natural variants of the active site cysteine were examined and found to be capable of biosynthesis, suggesting possible direct loading of starter units onto the β-ketoacyl synthase (KS) domain. In light of the data assembled here, the predictable synthesis of unnatural products by NR-PKSs is more fully defined.
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Affiliation(s)
- Callie R. Huitt-Roehl
- Department of Chemistry, Johns Hopkins University, 3400 N. Charles
Street, Baltimore, Maryland 21218, United States
| | - Eric A. Hill
- Department of Chemistry, Johns Hopkins University, 3400 N. Charles
Street, Baltimore, Maryland 21218, United States
| | - Martina M. Adams
- Department of Chemistry, Johns Hopkins University, 3400 N. Charles
Street, Baltimore, Maryland 21218, United States
| | - Anna L. Vagstad
- Department of Chemistry, Johns Hopkins University, 3400 N. Charles
Street, Baltimore, Maryland 21218, United States
| | - Jesse W. Li
- Department of Chemistry, Johns Hopkins University, 3400 N. Charles
Street, Baltimore, Maryland 21218, United States
| | - Craig A. Townsend
- Department of Chemistry, Johns Hopkins University, 3400 N. Charles
Street, Baltimore, Maryland 21218, United States
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25
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Vederas JC. Explorations of fungal biosynthesis of reduced polyketides – a personal viewpoint. Nat Prod Rep 2014; 31:1253-9. [DOI: 10.1039/c4np00091a] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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26
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Diversity-oriented combinatorial biosynthesis of benzenediol lactone scaffolds by subunit shuffling of fungal polyketide synthases. Proc Natl Acad Sci U S A 2014; 111:12354-9. [PMID: 25049383 DOI: 10.1073/pnas.1406999111] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Combinatorial biosynthesis aspires to exploit the promiscuity of microbial anabolic pathways to engineer the synthesis of new chemical entities. Fungal benzenediol lactone (BDL) polyketides are important pharmacophores with wide-ranging bioactivities, including heat shock response and immune system modulatory effects. Their biosynthesis on a pair of sequentially acting iterative polyketide synthases (iPKSs) offers a test case for the modularization of secondary metabolic pathways into "build-couple-pair" combinatorial synthetic schemes. Expression of random pairs of iPKS subunits from four BDL model systems in a yeast heterologous host created a diverse library of BDL congeners, including a polyketide with an unnatural skeleton and heat shock response-inducing activity. Pairwise heterocombinations of the iPKS subunits also helped to illuminate the innate, idiosyncratic programming of these enzymes. Even in combinatorial contexts, these biosynthetic programs remained largely unchanged, so that the iPKSs built their cognate biosynthons, coupled these building blocks into chimeric polyketide intermediates, and catalyzed intramolecular pairing to release macrocycles or α-pyrones. However, some heterocombinations also provoked stuttering, i.e., the relaxation of iPKSs chain length control to assemble larger homologous products. The success of such a plug and play approach to biosynthesize novel chemical diversity bodes well for bioprospecting unnatural polyketides for drug discovery.
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27
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Newman AG, Vagstad AL, Storm P, Townsend CA. Systematic domain swaps of iterative, nonreducing polyketide synthases provide a mechanistic understanding and rationale for catalytic reprogramming. J Am Chem Soc 2014; 136:7348-62. [PMID: 24815013 PMCID: PMC4046768 DOI: 10.1021/ja5007299] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2014] [Indexed: 11/29/2022]
Abstract
Iterative, nonreducing polyketide synthases (NR-PKSs) are multidomain enzymes responsible for the construction of the core architecture of aromatic polyketide natural products in fungi. Engineering these enzymes for the production of non-native metabolites has been a long-standing goal. We conducted a systematic survey of in vitro "domain swapped" NR-PKSs using an enzyme deconstruction approach. The NR-PKSs were dissected into mono- to multidomain fragments and recombined as noncognate pairs in vitro, reconstituting enzymatic activity. The enzymes used in this study produce aromatic polyketides that are representative of the four main chemical features set by the individual NR-PKS: starter unit selection, chain-length control, cyclization register control, and product release mechanism. We found that boundary conditions limit successful chemistry, which are dependent on a set of underlying enzymatic mechanisms. Crucial for successful redirection of catalysis, the rate of productive chemistry must outpace the rate of spontaneous derailment and thioesterase-mediated editing. Additionally, all of the domains in a noncognate system must interact efficiently if chemical redirection is to proceed. These observations refine and further substantiate current understanding of the mechanisms governing NR-PKS catalysis.
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Affiliation(s)
- Adam G. Newman
- Department of Chemistry, The Johns Hopkins
University, 3400 N. Charles
Street, Baltimore, Maryland 21218, United States
| | | | - Philip
A. Storm
- Department of Chemistry, The Johns Hopkins
University, 3400 N. Charles
Street, Baltimore, Maryland 21218, United States
| | - Craig A. Townsend
- Department of Chemistry, The Johns Hopkins
University, 3400 N. Charles
Street, Baltimore, Maryland 21218, United States
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28
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Weissman KJ. Probing interactions in fungal PKS. ACTA ACUST UNITED AC 2014; 20:1089-91. [PMID: 24054181 DOI: 10.1016/j.chembiol.2013.09.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Biosynthesis of polyketides can depend on interactions between the acyl carrier proteins (ACPs) which hold the growing chains and their enzymatic partners. In this issue of Chemistry & Biology, Bruegger and colleagues demonstrate that mechanism-based probes tethered to the ACPs of fungal nonreducing polyketide synthases can provide insights into these contacts.
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Affiliation(s)
- Kira J Weissman
- Molecular and Structural Enzymology Group, UMR 7365 CNRS-UL:IMoPA, Lorraine University, Faculté de Médecine, Batiment Biopôle, 9 Avenue de la Forêt de Haye, BP 184, 54506 Vandoeuvre-lès-Nancy, France.
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29
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Liu T, Sanchez JF, Chiang YM, Oakley BR, Wang CCC. Rational domain swaps reveal insights about chain length control by ketosynthase domains in fungal nonreducing polyketide synthases. Org Lett 2014; 16:1676-9. [PMID: 24593241 PMCID: PMC3993715 DOI: 10.1021/ol5003384] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
![]()
A facile
genetic methodology in the filamentous fungus Aspergillus
nidulans allowed exchange of the starter unit ACP transacylase
(SAT) domain
in the nonreduced polyketide synthase (NR-PKS) AfoE of the asperfuranone
pathway with the SAT domains from 10 other NR-PKSs. The newly created
hybrid with the NR-PKS AN3386 is able to accept a longer starter unit
in place of the native substrate to create a novel aromatic polyketide in vivo.
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Affiliation(s)
- Ting Liu
- Department of Pharmacology and Pharmaceutical Sciences, University of Southern California, School of Pharmacy , Los Angeles, California 90089, United States
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30
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Cummings M, Breitling R, Takano E. Steps towards the synthetic biology of polyketide biosynthesis. FEMS Microbiol Lett 2014; 351:116-25. [PMID: 24372666 PMCID: PMC4237116 DOI: 10.1111/1574-6968.12365] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2013] [Revised: 12/16/2013] [Accepted: 12/17/2013] [Indexed: 11/29/2022] Open
Abstract
Nature is providing a bountiful pool of valuable secondary metabolites, many of which possess therapeutic properties. However, the discovery of new bioactive secondary metabolites is slowing down, at a time when the rise of multidrug-resistant pathogens and the realization of acute and long-term side effects of widely used drugs lead to an urgent need for new therapeutic agents. Approaches such as synthetic biology are promising to deliver a much-needed boost to secondary metabolite drug development through plug-and-play optimized hosts and refactoring novel or cryptic bacterial gene clusters. Here, we discuss this prospect focusing on one comprehensively studied class of clinically relevant bioactive molecules, the polyketides. Extensive efforts towards optimization and derivatization of compounds via combinatorial biosynthesis and classical engineering have elucidated the modularity, flexibility and promiscuity of polyketide biosynthetic enzymes. Hence, a synthetic biology approach can build upon a solid basis of guidelines and principles, while providing a new perspective towards the discovery and generation of novel and new-to-nature compounds. We discuss the lessons learned from the classical engineering of polyketide synthases and indicate their importance when attempting to engineer biosynthetic pathways using synthetic biology approaches for the introduction of novelty and overexpression of products in a controllable manner.
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Affiliation(s)
- Matthew Cummings
- Faculty of Life Sciences, Manchester Institute of Biotechnology, The University of ManchesterManchester, UK
| | - Rainer Breitling
- Faculty of Life Sciences, Manchester Institute of Biotechnology, The University of ManchesterManchester, UK
| | - Eriko Takano
- Faculty of Life Sciences, Manchester Institute of Biotechnology, The University of ManchesterManchester, UK
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31
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Soehano I, Yang L, Ding F, Sun H, Low ZJ, Liu X, Liang ZX. Insights into the programmed ketoreduction of partially reducing polyketide synthases: stereo- and substrate-specificity of the ketoreductase domain. Org Biomol Chem 2014; 12:8542-9. [DOI: 10.1039/c4ob01777c] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Evidence are provided to support that partially reducing polyketide synthases achieve programmed ketoreduction by differential recognition of polyketide intermediates.
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Affiliation(s)
- Ishin Soehano
- School of Biological Sciences Nanyang Technological University
- , Singapore
| | - Lifeng Yang
- School of Biological Sciences Nanyang Technological University
- , Singapore
| | - Feiqing Ding
- School of Mathematics and Physics
- Nanyang Technological University
- , Singapore
| | - Huihua Sun
- School of Biological Sciences Nanyang Technological University
- , Singapore
| | - Zhen Jie Low
- School of Biological Sciences Nanyang Technological University
- , Singapore
| | - Xuewei Liu
- School of Mathematics and Physics
- Nanyang Technological University
- , Singapore
| | - Zhao-Xun Liang
- School of Biological Sciences Nanyang Technological University
- , Singapore
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32
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Xu Y, Zhou T, Zhang S, Xuan LJ, Zhan J, Molnár I. Thioesterase domains of fungal nonreducing polyketide synthases act as decision gates during combinatorial biosynthesis. J Am Chem Soc 2013; 135:10783-91. [PMID: 23822773 PMCID: PMC3780601 DOI: 10.1021/ja4041362] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
A crucial step during the programmed biosynthesis of fungal polyketide natural products is the release of the final polyketide intermediate from the iterative polyketide synthases (iPKSs), most frequently by a thioesterase (TE) domain. Realization of combinatorial biosynthesis with iPKSs requires TE domains that can accept altered polyketide intermediates generated by hybrid synthase enzymes and successfully release "unnatural products" with the desired structure. Achieving precise control over product release is of paramount importance with O-C bond-forming TE domains capable of macrocyclization, hydrolysis, transesterification, and pyrone formation that channel reactive, pluripotent polyketide intermediates to defined structural classes of bioactive secondary metabolites. By exploiting chimeric iPKS enzymes to offer substrates with controlled structural variety to two orthologous O-C bond-forming TE domains in situ, we show that these enzymes act as nonequivalent decision gates, determining context-dependent release mechanisms and overall product flux. Inappropriate choice of a TE could eradicate product formation in an otherwise highly productive chassis. Conversely, a judicious choice of a TE may allow the production of a desired hybrid metabolite. Finally, a serendipitous choice of a TE may reveal the unexpected productivity of some chassis. The ultimate decision gating role of TE domains influences the observable outcome of combinatorial domain swaps, emphasizing that the deduced programming rules are context dependent. These factors may complicate engineering the biosynthesis of a desired "unnatural product" but may also open additional avenues to create biosynthetic novelty based on fungal nonreduced polyketides.
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Affiliation(s)
- Yuquan Xu
- Natural Products Center, School of Natural Resources and the Environment, The University of Arizona, 250 E. Valencia Rd., Tucson, AZ 85706, USA
| | - Tong Zhou
- Department of Biological Engineering, Utah State University, 4105 Old Main Hill, Logan, UT 84322, USA
| | - Shuwei Zhang
- Department of Biological Engineering, Utah State University, 4105 Old Main Hill, Logan, UT 84322, USA
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Shanghai Institute for Biological Sciences, Chinese Academy of Sciences, 501 Haike Road, Zhangjiang Hi-Tech Park, Shanghai 201203, China
| | - Li-Jiang Xuan
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Shanghai Institute for Biological Sciences, Chinese Academy of Sciences, 501 Haike Road, Zhangjiang Hi-Tech Park, Shanghai 201203, China
| | - Jixun Zhan
- Department of Biological Engineering, Utah State University, 4105 Old Main Hill, Logan, UT 84322, USA
| | - István Molnár
- Natural Products Center, School of Natural Resources and the Environment, The University of Arizona, 250 E. Valencia Rd., Tucson, AZ 85706, USA
- Bio5 Institute, The University of Arizona, 1657 E. Helen St., Tucson, AZ 85721, USA
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33
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Li XW, Ear A, Nay B. Hirsutellones and beyond: figuring out the biological and synthetic logics toward chemical complexity in fungal PKS-NRPS compounds. Nat Prod Rep 2013; 30:765-82. [PMID: 23640165 DOI: 10.1039/c3np70016j] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Covering: up to early 2013. Fungal polyketides and their hybrid non ribosomal peptide derivatives are characterized by often striking structural features and biological activities. Their diversity and their complexity arise from highly organized and programmable biosynthetic pathways and have been challenged by many synthetic chemists. This review will conceptually illustrate how complexity can be generated, starting from a general biosynthetic purpose (the fundaments of PKS-NRPS assembly lines) and finally showing how the particular class of hirsutellone compounds has emerged from such processes in relation to post-elongation and secondary tailoring events. Synthetic efforts to produce these natural products will be described with a special emphasis on complexity-generating strategies and steps. Thus, the biosynthetic and synthetic works will be analyzed in a continuous flow, focusing on both the logic of Nature and organic chemists.
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Affiliation(s)
- Xu-Wen Li
- Muséum National d'Histoire Naturelle, Molécules de Communication et Adaptation des Micro-organismes (UMR 7245 CNRS-MNHN), 57 rue Cuvier (CP 54), 75005 Paris, France
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34
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Xu Y, Zhou T, Zhou Z, Su S, Roberts SA, Montfort WR, Zeng J, Chen M, Zhang W, Lin M, Zhan J, Molnár I. Rational reprogramming of fungal polyketide first-ring cyclization. Proc Natl Acad Sci U S A 2013; 110:5398-403. [PMID: 23509261 PMCID: PMC3619332 DOI: 10.1073/pnas.1301201110] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Resorcylic acid lactones and dihydroxyphenylacetic acid lactones represent important pharmacophores with heat shock response and immune system modulatory activities. The biosynthesis of these fungal polyketides involves a pair of collaborating iterative polyketide synthases (iPKSs): a highly reducing iPKS with product that is further elaborated by a nonreducing iPKS (nrPKS) to yield a 1,3-benzenediol moiety bridged by a macrolactone. Biosynthesis of unreduced polyketides requires the sequestration and programmed cyclization of highly reactive poly-β-ketoacyl intermediates to channel these uncommitted, pluripotent substrates to defined subsets of the polyketide structural space. Catalyzed by product template (PT) domains of the fungal nrPKSs and discrete aromatase/cyclase enzymes in bacteria, regiospecific first-ring aldol cyclizations result in characteristically different polyketide folding modes. However, a few fungal polyketides, including the dihydroxyphenylacetic acid lactone dehydrocurvularin, derive from a folding event that is analogous to the bacterial folding mode. The structural basis of such a drastic difference in the way a PT domain acts has not been investigated until now. We report here that the fungal vs. bacterial folding mode difference is portable on creating hybrid enzymes, and we structurally characterize the resulting unnatural products. Using structure-guided active site engineering, we unravel structural contributions to regiospecific aldol condensations and show that reshaping the cyclization chamber of a PT domain by only three selected point mutations is sufficient to reprogram the dehydrocurvularin nrPKS to produce polyketides with a fungal fold. Such rational control of first-ring cyclizations will facilitate efforts to the engineered biosynthesis of novel chemical diversity from natural unreduced polyketides.
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Affiliation(s)
- Yuquan Xu
- Natural Products Center, School of Natural Resources and the Environment, University of Arizona, Tucson, AZ 85706
| | - Tong Zhou
- Department of Biological Engineering, Utah State University, Logan, UT 84322
| | - Zhengfu Zhou
- Natural Products Center, School of Natural Resources and the Environment, University of Arizona, Tucson, AZ 85706
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, People’s Republic of China; and
| | - Shiyou Su
- Natural Products Center, School of Natural Resources and the Environment, University of Arizona, Tucson, AZ 85706
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, People’s Republic of China; and
| | | | - William R. Montfort
- Department of Chemistry and Biochemistry and
- Bio5 Institute, University of Arizona, Tucson, AZ 85721
| | - Jia Zeng
- Department of Biological Engineering, Utah State University, Logan, UT 84322
| | - Ming Chen
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, People’s Republic of China; and
| | - Wei Zhang
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, People’s Republic of China; and
| | - Min Lin
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, People’s Republic of China; and
| | - Jixun Zhan
- Department of Biological Engineering, Utah State University, Logan, UT 84322
| | - István Molnár
- Natural Products Center, School of Natural Resources and the Environment, University of Arizona, Tucson, AZ 85706
- Bio5 Institute, University of Arizona, Tucson, AZ 85721
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