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Fallon TR, Shende VV, Wierzbicki IH, Pendleton AL, Watervoort NF, Auber RP, Gonzalez DJ, Wisecaver JH, Moore BS. Giant polyketide synthase enzymes in the biosynthesis of giant marine polyether toxins. Science 2024; 385:671-678. [PMID: 39116217 DOI: 10.1126/science.ado3290] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Accepted: 07/10/2024] [Indexed: 08/10/2024]
Abstract
Prymnesium parvum are harmful haptophyte algae that cause massive environmental fish kills. Their polyketide polyether toxins, the prymnesins, are among the largest nonpolymeric compounds in nature and have biosynthetic origins that have remained enigmatic for more than 40 years. In this work, we report the "PKZILLAs," massive P. parvum polyketide synthase (PKS) genes that have evaded previous detection. PKZILLA-1 and -2 encode giant protein products of 4.7 and 3.2 megadaltons that have 140 and 99 enzyme domains. Their predicted polyene product matches the proposed pre-prymnesin precursor of the 90-carbon-backbone A-type prymnesins. We further characterize the variant PKZILLA-B1, which is responsible for the shorter B-type analog prymnesin-B1, from P. parvum RCC3426 and thus establish a general model of haptophyte polyether biosynthetic logic. This work expands expectations of genetic and enzymatic size limits in biology.
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Affiliation(s)
- Timothy R Fallon
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography and University of California, San Diego, La Jolla, CA 92093, USA
| | - Vikram V Shende
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography and University of California, San Diego, La Jolla, CA 92093, USA
| | - Igor H Wierzbicki
- Department of Pharmacology, University of California, San Diego, La Jolla, CA 92093, USA
| | - Amanda L Pendleton
- Department of Biochemistry, Purdue University, West Lafayette, IN 47907, USA
- Purdue Center for Plant Biology, Purdue University, West Lafayette, IN 47907, USA
| | - Nathan F Watervoort
- Department of Biochemistry, Purdue University, West Lafayette, IN 47907, USA
- Purdue Center for Plant Biology, Purdue University, West Lafayette, IN 47907, USA
| | - Robert P Auber
- Department of Biochemistry, Purdue University, West Lafayette, IN 47907, USA
- Purdue Center for Plant Biology, Purdue University, West Lafayette, IN 47907, USA
| | - David J Gonzalez
- Department of Pharmacology, University of California, San Diego, La Jolla, CA 92093, USA
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA 92093, USA
| | - Jennifer H Wisecaver
- Department of Biochemistry, Purdue University, West Lafayette, IN 47907, USA
- Purdue Center for Plant Biology, Purdue University, West Lafayette, IN 47907, USA
| | - Bradley S Moore
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography and University of California, San Diego, La Jolla, CA 92093, USA
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA 92093, USA
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2
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Place AR, Ramos-Franco J, Waters AL, Peng J, Hamann MT. Sterolysin from a 1950s culture of Karlodinium veneficum (aka Gymnodinium veneficum Ballantine) forms lethal sterol dependent membrane pores. Sci Rep 2024; 14:17998. [PMID: 39097621 PMCID: PMC11297910 DOI: 10.1038/s41598-024-68669-0] [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: 02/19/2024] [Accepted: 07/26/2024] [Indexed: 08/05/2024] Open
Abstract
In 1957 Abbott and Ballantine described a highly toxic activity from a dinoflagellate isolated from the English Channel in 1949 by Mary Park. From a culture maintained at Plymouth Laboratory since 1950, we have been able to isolate two toxic molecules (abbotoxin and 59-E-Chloro-abbotoxin), determine the planar structures by analysis of HRMS and 1D and 2D NMR spectra, and found them to be karlotoxin (KmTx) congeners. Both toxins kill larval zebrafish with symptoms identical to those described by Abbot and Ballantine for gobies (Gobius virescens). Using surface plasma resonance the sterol binding specificity of karlotoxins is shown to require desmethyl sterols. Our results with black lipid membranes indicate that karlotoxin forms large-conductance channels in the lipid membrane, which are characterized by large ionic conductance, poor ionic selectivity, and a complex gating behavior that exhibits strong voltage dependence and multiple gating patterns. In addition, we show that KmTx 2 pore formation is a highly targeted mechanism involving sterol-specificity. This is the first report of the functional properties of the membrane pores formed by karlotoxins and is consistent with the initial observations of Abbott and Ballantine from 1957.
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Affiliation(s)
- Allen R Place
- Institute of Marine and Environmental Technology, University of Maryland Center for Environmental Sciences, Suite 236 Rita Rossi Colwell Center, Baltimore, MD, 21202, USA.
| | - Josefina Ramos-Franco
- Department of Physiology and Biophysics, Rush University Medical Center, Chicago, IL, 60612, USA
| | - Amanda L Waters
- Department of Chemistry, University of Central Oklahoma, Edmond, OK, 73034, USA
| | - Jiangnan Peng
- Department of Chemistry, Morgan State University, Baltimore, MD, 21251, USA
- COP Drug Discovery and Biomedical Sciences, Medical University of South Carolina, Charleston, SC, 29425-5700, USA
| | - Mark T Hamann
- Department of Chemistry, Morgan State University, Baltimore, MD, 21251, USA
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3
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Hess SN, Fürstner A. An Efficient and Scalable "Second Generation" Total Synthesis of the Marine Polyketide Limaol Endowed with Antiparasitic Activity. Chemistry 2024; 30:e202401429. [PMID: 38716817 DOI: 10.1002/chem.202401429] [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: 04/12/2024] [Indexed: 06/20/2024]
Abstract
The cluster of four skipped exo-methylene substituents on the "northern" wing of limaol renders this dinoflagellate-derived marine natural product unique in structural terms. This arguably non-thermodynamic array gains kinetic stability by virtue of populating local conformations which impede isomerization to a partly or fully conjugated polyene. This analysis suggested that the difficulties encountered during the late stages of our first total synthesis of this polyketide had not been caused by an overly fragile character of this unusual substructure; rather, an unfavorable steric microenvironment about the spirotricyclic core was identified as the likely cause. To remedy the issue, the protecting groups on this central fragment were changed; in effect, this amendment allowed all strategic and practical problems to be addressed. As a result, the overall yield over the longest linear sequence was multiplied by a factor of almost five and the material throughput increased more than eighty-fold per run. Key-to-success was a gold-catalyzed spirocyclization reaction; the reasons why a Brønsted acid cocatalyst is needed and the origin of the excellent levels of selectivity were delineated. The change of the protecting groups also allowed for much improved fragment coupling processes; most notably, the sequence of a substrate-controlled carbonyl addition reaction followed by Mitsunobu inversion that had originally been necessary to affix the southern tail to the core could be replaced by a reagent controlled asymmetric allylation. Finally, a much-improved route to the "northern" sector was established by leveraging the power of asymmetric hydrogenation of a 2-pyrone derivative. Limaol was found to combine appreciable antiparasitic activity with very modest cytotoxicity.
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Affiliation(s)
- Stephan N Hess
- Max-Planck-Institut für Kohlenforschung, 45470, Mülheim/Ruhr, Germany
| | - Alois Fürstner
- Max-Planck-Institut für Kohlenforschung, 45470, Mülheim/Ruhr, Germany
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4
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Xu SY, Mo YH, Liu YJ, Wang X, Li HY, Yang WD. Physiological and genetic responses of the benthic dinoflagellate Prorocentrum lima to polystyrene microplastics. HARMFUL ALGAE 2024; 136:102652. [PMID: 38876530 DOI: 10.1016/j.hal.2024.102652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2024] [Revised: 05/13/2024] [Accepted: 05/20/2024] [Indexed: 06/16/2024]
Abstract
Microplastics are well known as contaminants in marine environments. With the development of biofilms, most microplastics will eventually sink and deposit in benthic environment. However, little research has been done on benthic toxic dinoflagellates, and the effects of microplastics on benthic dinoflagellates are unknown. Prorocentrum lima is a cosmopolitan toxic benthic dinoflagellate, which can produce a range of polyether metabolites, such as diarrhetic shellfish poisoning (DSP) toxins. In order to explore the impact of microplastics on marine benthic dinoflagellates, in this paper, we studied the effects of polystyrene (PS) on the growth and toxin production of P. lima. The molecular response of P. lima to microplastic stress was analyzed by transcriptomics. We selected 100 nm, 10 μm and 100 μm PS, and set three concentrations of 1 mg L-1, 10 mg L-1 and 100 mg L-1. The results showed that PS exposure had limited effects on cell growth, but increased the OA and extracellular polysaccharide content at high concentrations. After exposure to PS MPs, genes associated with DSP toxins synthesis, carbohydrate synthesis and energy metabolism, such as glycolysis, TCA cycle and pyruvate metabolism, were significantly up-regulated. We speculated that after exposure to microplastics, P. lima may increase the synthesis of DSP toxins and extracellular polysaccharides, improve the level of energy metabolism and gene expression of ABC transporter, thereby protecting algal cells from damage. Our findings provide new insights into the effects of microplastics on toxic benthic dinoflagellates.
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Affiliation(s)
- Si-Yuan Xu
- Key Laboratory of Aquatic Eutrophication and Control of Harmful Algal Blooms of Guangdong Higher Education Institute, College of Life Science and Technology, Jinan University, Guangzhou 510632, PR China
| | - Yan-Hang Mo
- Key Laboratory of Aquatic Eutrophication and Control of Harmful Algal Blooms of Guangdong Higher Education Institute, College of Life Science and Technology, Jinan University, Guangzhou 510632, PR China
| | - Yu-Jie Liu
- Key Laboratory of Aquatic Eutrophication and Control of Harmful Algal Blooms of Guangdong Higher Education Institute, College of Life Science and Technology, Jinan University, Guangzhou 510632, PR China
| | - Xiang Wang
- Key Laboratory of Aquatic Eutrophication and Control of Harmful Algal Blooms of Guangdong Higher Education Institute, College of Life Science and Technology, Jinan University, Guangzhou 510632, PR China
| | - Hong-Ye Li
- Key Laboratory of Aquatic Eutrophication and Control of Harmful Algal Blooms of Guangdong Higher Education Institute, College of Life Science and Technology, Jinan University, Guangzhou 510632, PR China
| | - Wei-Dong Yang
- Key Laboratory of Aquatic Eutrophication and Control of Harmful Algal Blooms of Guangdong Higher Education Institute, College of Life Science and Technology, Jinan University, Guangzhou 510632, PR China.
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Fallon TR, Shende VV, Wierzbicki IH, Auber RP, Gonzalez DJ, Wisecaver JH, Moore BS. Giant polyketide synthase enzymes biosynthesize a giant marine polyether biotoxin. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.29.577497. [PMID: 38352448 PMCID: PMC10862718 DOI: 10.1101/2024.01.29.577497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/22/2024]
Abstract
Prymnesium parvum are harmful haptophyte algae that cause massive environmental fish-kills. Their polyketide polyether toxins, the prymnesins, are amongst the largest nonpolymeric compounds in nature, alongside structurally-related health-impacting "red-tide" polyether toxins whose biosynthetic origins have been an enigma for over 40 years. Here we report the 'PKZILLAs', massive P. parvum polyketide synthase (PKS) genes, whose existence and challenging genomic structure evaded prior detection. PKZILLA-1 and -2 encode giant protein products of 4.7 and 3.2 MDa with 140 and 99 enzyme domains, exceeding the largest known protein titin and all other known PKS systems. Their predicted polyene product matches the proposed pre-prymnesin precursor of the 90-carbon-backbone A-type prymnesins. This discovery establishes a model system for microalgal polyether biosynthesis and expands expectations of genetic and enzymatic size limits in biology.
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Affiliation(s)
- Timothy R. Fallon
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography and University of California, San Diego; 9500 Gilman Dr #0204, La Jolla, CA 92093, USA
| | - Vikram V. Shende
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography and University of California, San Diego; 9500 Gilman Dr #0204, La Jolla, CA 92093, USA
| | - Igor H. Wierzbicki
- Department of Pharmacology, University of California, San Diego; 9500 Gilman Dr, La Jolla, CA 92093, USA
| | - Robert P. Auber
- Department of Biochemistry, Purdue University; 175 S University St, West Lafayette, IN 47907, USA
- Purdue Center for Plant Biology, Purdue University; 175 S University St, West Lafayette, IN 47907, USA
| | - David J. Gonzalez
- Department of Pharmacology, University of California, San Diego; 9500 Gilman Dr, La Jolla, CA 92093, USA
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego; 9500 Gilman Dr, La Jolla, CA 92093, USA
| | - Jennifer H. Wisecaver
- Department of Biochemistry, Purdue University; 175 S University St, West Lafayette, IN 47907, USA
- Purdue Center for Plant Biology, Purdue University; 175 S University St, West Lafayette, IN 47907, USA
| | - Bradley S. Moore
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography and University of California, San Diego; 9500 Gilman Dr #0204, La Jolla, CA 92093, USA
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego; 9500 Gilman Dr, La Jolla, CA 92093, USA
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6
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Tang J, Li W, Chiu TY, Martínez-Peña F, Luo Z, Chong CT, Wei Q, Gazaniga N, West TJ, See YY, Lairson LL, Parker CG, Baran PS. Synthesis of portimines reveals the basis of their anti-cancer activity. Nature 2023; 622:507-513. [PMID: 37730997 PMCID: PMC10699793 DOI: 10.1038/s41586-023-06535-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Accepted: 08/11/2023] [Indexed: 09/22/2023]
Abstract
Marine-derived cyclic imine toxins, portimine A and portimine B, have attracted attention because of their chemical structure and notable anti-cancer therapeutic potential1-4. However, access to large quantities of these toxins is currently not feasible, and the molecular mechanism underlying their potent activity remains unknown until now. To address this, a scalable and concise synthesis of portimines is presented, which benefits from the logic used in the two-phase terpenoid synthesis5,6 along with other tactics such as exploiting ring-chain tautomerization and skeletal reorganization to minimize protecting group chemistry through self-protection. Notably, this total synthesis enabled a structural reassignment of portimine B and an in-depth functional evaluation of portimine A, revealing that it induces apoptosis selectively in human cancer cell lines with high potency and is efficacious in vivo in tumour-clearance models. Finally, practical access to the portimines and their analogues simplified the development of photoaffinity analogues, which were used in chemical proteomic experiments to identify a primary target of portimine A as the 60S ribosomal export protein NMD3.
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Affiliation(s)
- Junchen Tang
- Department of Chemistry, Scripps Research, La Jolla, CA, USA
| | - Weichao Li
- Department of Chemistry, Scripps Research, La Jolla, CA, USA
| | - Tzu-Yuan Chiu
- Department of Chemistry, Scripps Research, La Jolla, CA, USA
| | | | - Zengwei Luo
- Department of Chemistry, Scripps Research, La Jolla, CA, USA
| | | | - Qijia Wei
- Department of Chemistry, Scripps Research, La Jolla, CA, USA
| | | | - Thomas J West
- Department of Chemistry, Scripps Research, La Jolla, CA, USA
| | - Yi Yang See
- Department of Chemistry, Scripps Research, La Jolla, CA, USA
| | - Luke L Lairson
- Department of Chemistry, Scripps Research, La Jolla, CA, USA.
| | | | - Phil S Baran
- Department of Chemistry, Scripps Research, La Jolla, CA, USA.
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7
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D'Ambrosio HK, Keeler AM, Derbyshire ER. Examination of Secondary Metabolite Biosynthesis in Apicomplexa. Chembiochem 2023; 24:e202300263. [PMID: 37171468 DOI: 10.1002/cbic.202300263] [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: 04/01/2023] [Revised: 05/11/2023] [Accepted: 05/12/2023] [Indexed: 05/13/2023]
Abstract
Natural product discovery has traditionally relied on the isolation of small molecules from producing species, but genome-sequencing technology and advances in molecular biology techniques have expanded efforts to a wider array of organisms. Protists represent an underexplored kingdom for specialized metabolite searches despite bioinformatic analysis that suggests they harbor distinct biologically active small molecules. Specifically, pathogenic apicomplexan parasites, responsible for billions of global infections, have been found to possess multiple biosynthetic gene clusters, which hints at their capacity to produce polyketide metabolites. Biochemical studies have revealed unique features of apicomplexan polyketide synthases, but to date, the identity and function of the polyketides synthesized by these megaenzymes remains unknown. Herein, we discuss the potential for specialized metabolite production in protists and the possible evolution of polyketide biosynthetic gene clusters in apicomplexan parasites. We then focus on a polyketide synthase from the apicomplexan Toxoplasma gondii to discuss the unique domain architecture and properties of these proteins when compared to previously characterized systems, and further speculate on the possible functions for polyketides in these pathogenic parasites.
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Affiliation(s)
- Hannah K D'Ambrosio
- Department of Chemistry, Duke University, 124 Science Drive, Durham, NC 27708, USA
| | - Aaron M Keeler
- Department of Chemistry, Duke University, 124 Science Drive, Durham, NC 27708, USA
| | - Emily R Derbyshire
- Department of Chemistry, Duke University, 124 Science Drive, Durham, NC 27708, USA
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, 213 Research Drive, Durham, NC 27710, USA
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8
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Stonik VA, Stonik IV. Carbohydrate-Containing Low Molecular Weight Metabolites of Microalgae. Mar Drugs 2023; 21:427. [PMID: 37623708 PMCID: PMC10456119 DOI: 10.3390/md21080427] [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: 06/28/2023] [Revised: 07/24/2023] [Accepted: 07/26/2023] [Indexed: 08/26/2023] Open
Abstract
Microalgae are abundant components of the biosphere rich in low molecular weight carbohydrate-containing natural products (glycoconjugates). Glycoconjugates take part in the processes of photosynthesis, provide producers with important biological molecules, influence other organisms and are known by their biological activities. Some of them, for example, glycosylated toxins and arsenicals, are detrimental and can be transferred via food chains into higher organisms, including humans. So far, the studies on a series of particular groups of microalgal glycoconjugates were not comprehensively discussed in special reviews. In this review, a special focus is given to glycoconjugates' isolation, structure determination, properties and approaches to search for new bioactive metabolites. Analysis of literature data concerning structures, functions and biological activities of ribosylated arsenicals, galactosylated and sulfoquinovosylated lipids, phosphoglycolipids, glycoside derivatives of toxins, and other groups of glycoconjugates was carried out and discussed. Recent studies were fundamental in the discovery of a great variety of new carbohydrate-containing metabolites and their biological activities in defining the role of microalgal viral infections in regulating microalgal blooms as well as in the detection of glycoconjugates with potent immunomodulatory properties. Those discoveries support growing interest in these molecules.
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Affiliation(s)
- Valentin A. Stonik
- G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far Eastern Branch of the Russian Academy of Sciences, Pr. 100-letya Vladivostoka 159, 690022 Vladivostok, Russia;
| | - Inna V. Stonik
- A.V. Zhurmunsky National Scientific Center of Marine Biology, Far Eastern Branch, Russian Academy of Sciences, ul. Palchevskogo 17, 690041 Vladivostok, Russia
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9
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Haq S, Oyler BL, Williams E, Khan MM, Goodlett DR, Bachvaroff T, Place AR. Investigating A Multi-Domain Polyketide Synthase in Amphidinium carterae. Mar Drugs 2023; 21:425. [PMID: 37623706 PMCID: PMC10455422 DOI: 10.3390/md21080425] [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: 05/31/2023] [Revised: 07/14/2023] [Accepted: 07/25/2023] [Indexed: 08/26/2023] Open
Abstract
Dinoflagellates are unicellular organisms that are implicated in harmful algal blooms (HABs) caused by potent toxins that are produced through polyketide synthase (PKS) pathways. However, the exact mechanisms of toxin synthesis are unknown due to a lack of genomic segregation of fat, toxins, and other PKS-based pathways. To better understand the underlying mechanisms, the actions and expression of the PKS proteins were investigated using the toxic dinoflagellate Amphidinium carterae as a model. Cerulenin, a known ketosynthase inhibitor, was shown to reduce acetate incorporation into all fat classes with the toxins amphidinol and sulpho-amphidinol. The mass spectrometry analysis of cerulenin-reacted synthetic peptides derived from ketosynthase domains of A. carterae multimodular PKS transcripts demonstrated a strong covalent bond that could be localized using collision-induced dissociation. One multi-modular PKS sequence present in all dinoflagellates surveyed to date was found to lack an AT domain in toxin-producing species, indicating trans-acting domains, and was shown by Western blotting to be post-transcriptionally processed. These results demonstrate how toxin synthesis in dinoflagellates can be differentiated from fat synthesis despite common underlying pathway.
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Affiliation(s)
- Saddef Haq
- Institute for Marine and Environmental Technologies, University of Maryland Center for Environmental Science, 701 East Pratt St., Baltimore, MD 21202, USA; (S.H.); (E.W.); (T.B.)
| | - Benjamin L. Oyler
- University of Maryland School of Medicine, 655 W. Baltimore Street, Baltimore, MD 21201, USA; (B.L.O.); (M.M.K.)
| | - Ernest Williams
- Institute for Marine and Environmental Technologies, University of Maryland Center for Environmental Science, 701 East Pratt St., Baltimore, MD 21202, USA; (S.H.); (E.W.); (T.B.)
| | - Mohd M. Khan
- University of Maryland School of Medicine, 655 W. Baltimore Street, Baltimore, MD 21201, USA; (B.L.O.); (M.M.K.)
| | - David R. Goodlett
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC V8S 1P7, Canada;
| | - Tsvetan Bachvaroff
- Institute for Marine and Environmental Technologies, University of Maryland Center for Environmental Science, 701 East Pratt St., Baltimore, MD 21202, USA; (S.H.); (E.W.); (T.B.)
| | - Allen R. Place
- Institute for Marine and Environmental Technologies, University of Maryland Center for Environmental Science, 701 East Pratt St., Baltimore, MD 21202, USA; (S.H.); (E.W.); (T.B.)
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10
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Dong M, Li J, Yang D, Li M, Wei J. Biosynthesis and Pharmacological Activities of Flavonoids, Triterpene Saponins and Polysaccharides Derived from Astragalus membranaceus. Molecules 2023; 28:5018. [PMID: 37446680 PMCID: PMC10343288 DOI: 10.3390/molecules28135018] [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: 05/16/2023] [Revised: 06/19/2023] [Accepted: 06/25/2023] [Indexed: 07/15/2023] Open
Abstract
Astragalus membranaceus (A. membranaceus), a well-known traditional herbal medicine, has been widely used in ailments for more than 2000 years. The main bioactive compounds including flavonoids, triterpene saponins and polysaccharides obtained from A. membranaceus have shown a wide range of biological activities and pharmacological effects. These bioactive compounds have a significant role in protecting the liver, immunomodulation, anticancer, antidiabetic, antiviral, antiinflammatory, antioxidant and anti-cardiovascular activities. The flavonoids are initially synthesized through the phenylpropanoid pathway, followed by catalysis with corresponding enzymes, while the triterpenoid saponins, especially astragalosides, are synthesized through the universal upstream pathways of mevalonate (MVA) and methylerythritol phosphate (MEP), and the downstream pathway of triterpenoid skeleton formation and modification. Moreover, the Astragalus polysaccharide (APS) possesses multiple pharmacological activities. In this review, we comprehensively discussed the biosynthesis pathway of flavonoids and triterpenoid saponins, and the structural features of polysaccharides in A. membranaceus. We further systematically summarized the pharmacological effects of bioactive ingredients in A. membranaceus, which laid the foundation for the development of clinical candidate agents. Finally, we proposed potential strategies of heterologous biosynthesis to improve the industrialized production and sustainable supply of natural products with pharmacological activities from A. membranaceus, thereby providing an important guide for their future development trend.
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Affiliation(s)
- Miaoyin Dong
- College of Life Science and Technology, Gansu Agricultural University, Lanzhou 730070, China; (M.D.); (D.Y.)
- State Key Laboratory of Arid Land Crop Science, Gansu Agricultural University, Lanzhou 730070, China
| | - Jinjuan Li
- Institute of Agricultural Quality Standards and Testing Technology, Gansu Academy of Agricultural Sciences, Lanzhou 730070, China;
| | - Delong Yang
- College of Life Science and Technology, Gansu Agricultural University, Lanzhou 730070, China; (M.D.); (D.Y.)
- State Key Laboratory of Arid Land Crop Science, Gansu Agricultural University, Lanzhou 730070, China
| | - Mengfei Li
- State Key Laboratory of Arid Land Crop Science, Gansu Agricultural University, Lanzhou 730070, China
- Agronomy College, Gansu Agricultural University, Lanzhou 730070, China
| | - Jianhe Wei
- Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100193, China
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11
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Chen ZH, Guo YW, Li XW. Recent advances on marine mollusk-derived natural products: chemistry, chemical ecology and therapeutical potential. Nat Prod Rep 2023; 40:509-556. [PMID: 35942896 DOI: 10.1039/d2np00021k] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Covering: 2011-2021Marine mollusks, which are well known as rich sources of diverse and biologically active natural products, have attracted significant attention from researchers due to their chemical and pharmacological properties. The occurrence of some of these marine mollusk-derived natural products in their preys, predators, and associated microorganisms has also gained interest in chemical ecology research. Based on previous reviews, herein, we present a comprehensive summary of the recent advances of interesting secondary metabolites from marine mollusks, focusing on their structural features, possible chemo-ecological significance, and promising biological activities, covering the literature from 2011 to 2021.
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Affiliation(s)
- Zi-Hui Chen
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Zhangjiang Hi-Tech Park, Shanghai 201203, China.
- University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing 100049, China
| | - Yue-Wei Guo
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Zhangjiang Hi-Tech Park, Shanghai 201203, China.
- University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing 100049, China
- Shandong Laboratory of Yantai Drug Discovery, Bohai Rim Advanced Research Institute for Drug Discovery, Yantai, Shandong 264117, China
| | - Xu-Wen Li
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Zhangjiang Hi-Tech Park, Shanghai 201203, China.
- University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing 100049, China
- Shandong Laboratory of Yantai Drug Discovery, Bohai Rim Advanced Research Institute for Drug Discovery, Yantai, Shandong 264117, China
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12
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Hou A, Dickschat JS. Labelling studies in the biosynthesis of polyketides and non-ribosomal peptides. Nat Prod Rep 2023; 40:470-499. [PMID: 36484402 DOI: 10.1039/d2np00071g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Covering: 2015 to 2022In this review, we discuss the recent advances in the use of isotopically labelled compounds to investigate the biosynthesis of polyketides, non-ribosomally synthesised peptides, and their hybrids. Also, we highlight the use of isotopes in the elucidation of their structures and investigation of enzyme mechanisms. The biosynthetic pathways of selected examples are presented in detail to reveal the principles of the discussed labelling experiments. The presented examples demonstrate that the application of isotopically labelled compounds is still the state of the art and can provide valuable information for the biosynthesis of natural products.
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Affiliation(s)
- Anwei Hou
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, West 7th Avenue No. 32, 300308 Tianjin, China.,Institute of Microbiology, Jiangxi Academy of Sciences, Changdong Road No. 7777, 330096 Nanchang, China
| | - Jeroen S Dickschat
- Kekulé-Institute for Organic Chemistry and Biochemistry, University of Bonn, Gerhard-Domagk-Straße 1, 53121 Bonn, Germany.
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13
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Duan Y, Du W, Song Z, Chen R, Xie K, Liu J, Chen D, Dai J. Functional characterization of a cycloartenol synthase and four glycosyltransferases in the biosynthesis of cycloastragenol-type astragalosides from Astragalus membranaceus. Acta Pharm Sin B 2023; 13:271-283. [PMID: 36815054 PMCID: PMC9939298 DOI: 10.1016/j.apsb.2022.05.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Revised: 05/04/2022] [Accepted: 05/11/2022] [Indexed: 11/19/2022] Open
Abstract
Astragalosides are the main active constituents of traditional Chinese medicine Huang-Qi, of which cycloastragenol-type glycosides are the most typical and major bioactive compounds. This kind of compounds exhibit various biological functions including cardiovascular protective, neuroprotective, etc. Owing to the limitations of natural sources and the difficulties encountered in chemical synthesis, re-engineering of biosynthetic machinery will offer an alternative and promising approach to producing astragalosides. However, the biosynthetic pathway for astragalosides remains elusive due to their complex structures and numerous reaction types and steps. Herein, guided by transcriptome and phylogenetic analyses, a cycloartenol synthase and four glycosyltransferases catalyzing the committed steps in the biosynthesis of such bioactive astragalosides were functionally characterized from Astragalus membranaceus. AmCAS1, the first reported cycloartenol synthase from Astragalus genus, is capable of catalyzing the formation of cycloartenol; AmUGT15, AmUGT14, AmUGT13, and AmUGT7 are four glycosyltransferases biochemically characterized to catalyze 3-O-xylosylation, 3-O-glucosylation, 25-O-glucosylation/O-xylosylation and 2'-O-glucosylation of cycloastragenol glycosides, respectively. These findings not only clarified the crucial enzymes for the biosynthesis and the molecular basis for the structural diversity of astragalosides in Astragalus plants, also paved the way for further completely deciphering the biosynthetic pathway and constructing an artificial pathway for their efficient production.
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Affiliation(s)
| | | | - Zhijun Song
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, CAMS Key Laboratory of Enzyme and Biocatalysis of Natural Drugs, NHC Key Laboratory of Biosynthesis of Natural Products, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Ridao Chen
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, CAMS Key Laboratory of Enzyme and Biocatalysis of Natural Drugs, NHC Key Laboratory of Biosynthesis of Natural Products, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Kebo Xie
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, CAMS Key Laboratory of Enzyme and Biocatalysis of Natural Drugs, NHC Key Laboratory of Biosynthesis of Natural Products, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Jimei Liu
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, CAMS Key Laboratory of Enzyme and Biocatalysis of Natural Drugs, NHC Key Laboratory of Biosynthesis of Natural Products, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Dawei Chen
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, CAMS Key Laboratory of Enzyme and Biocatalysis of Natural Drugs, NHC Key Laboratory of Biosynthesis of Natural Products, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Jungui Dai
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, CAMS Key Laboratory of Enzyme and Biocatalysis of Natural Drugs, NHC Key Laboratory of Biosynthesis of Natural Products, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
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14
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Characterization of New Gambierones Produced by Gambierdiscus balechii 1123M1M10. Mar Drugs 2022; 21:md21010003. [PMID: 36662176 PMCID: PMC9866745 DOI: 10.3390/md21010003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Revised: 12/14/2022] [Accepted: 12/19/2022] [Indexed: 12/24/2022] Open
Abstract
The benthic dinoflagellate genus Gambierdiscus is the primary producer of toxins responsible for ciguatera poisoning (CP), a food intoxication endemic in tropical and subtropical areas of the world. We used high-performance liquid chromatography tandem high-resolution mass spectrometry (HPLC-HRMS) to investigate the toxin profile of Gambierdiscus balechii 1123M1M10, which was obtained from Marakei Island (2°01'N, 173°15'E), Republic of Kiribati, located in the central Pacific Ocean. Four new gambierone analogues including 12,13-dihydro-44-methylgambierone, 38-dehydroxy-12,13-dihydro-44-methylgambierone, 38-dehydroxy-44-methylgambierone, and desulfo-hydroxyl gambierone, and two known compounds, gambierone and 44-methylgambierone, were proposed by analyzing their fragmentation behaviors and pathways. Our findings provide new insights into the toxin profile of Gambierdiscus balechii 1123M1M10, which can be used as a biomarker for species identification, and lay the foundation for further toxin isolation and bioactivity studies of gambierones.
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15
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Morales-Amador A, Souto ML, Hertweck C, Fernández JJ, García-Altares M. Rapid Screening of Polyol Polyketides from Marine Dinoflagellates. Anal Chem 2022; 94:14205-14213. [PMID: 36190828 PMCID: PMC9583072 DOI: 10.1021/acs.analchem.2c02185] [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] [Indexed: 12/02/2022]
Abstract
![]()
Dinoflagellate-derived
polyketides are typically large molecules
(>1000 Da) with complex structures, potent bioactivities, and high
toxicities. Their discovery suffers three major bottlenecks: insufficient
bioavailability, low-yield cultivation of producer organisms, and
production of multiple highly related analogues by a single strain.
Consequently, the biotechnological production of therapeutics or toxicological
standards of dinoflagellate-derived polyketides is also hampered.
Strategies based on sensitive and selective techniques for chemical
prospection of dinoflagellate extracts could aid in overcoming these
limitations, as it allows selecting the most interesting candidates
for discovery and exploitation programs according to the biosynthetic
potential. In this work, we assess the combination of data-dependent
liquid chromatography coupled with high-resolution tandem mass spectrometry
(LC–HRMS2) and molecular networking to screen polyol
polyketides. To demonstrate the power of this approach, we selected
dinoflagellate Amphidinium carterae since it is commonly used as a biotechnological model and produces
amphidinols, a family of polyol-polyene compounds with antifungal
and antimycoplasmal activity. First, we screened families of compounds
with multiple hydroxyl groups by examining MS2 profiles
that contain sequential neutral losses of water. Then, we clustered
MS2 spectra by molecular networking to facilitate the dereplication
and discovery of amphidinols. Finally, we used the MS2 fragmentation
behavior of well-characterized luteophanol D as a model to propose
a structural hypothesis of nine novel amphidinols. We envision that
this strategy is a valuable approach to rapidly monitoring toxin production
of known and unknown polyol polyketides in dinoflagellates, even in
small culture volumes, and distinguishing strains according to their
toxin profiles.
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Affiliation(s)
- Adrián Morales-Amador
- Departamento de Química Orgánica, Instituto Universitario de Bio-Orgánica Antonio González (IUBO AG), Universidad de La Laguna (ULL), Avenida Astrofísico Francisco Sánchez 2, 38206 La Laguna, Tenerife, Spain.,Department of Biomolecular Chemistry, Leibniz Institute for Natural Products Research and Infection Biology, Hans Knöll Institute (HKI), Adolf-Reichwein-Straße 23, 07745 Jena, Germany
| | - María L Souto
- Departamento de Química Orgánica, Instituto Universitario de Bio-Orgánica Antonio González (IUBO AG), Universidad de La Laguna (ULL), Avenida Astrofísico Francisco Sánchez 2, 38206 La Laguna, Tenerife, Spain
| | - Christian Hertweck
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Products Research and Infection Biology, Hans Knöll Institute (HKI), Adolf-Reichwein-Straße 23, 07745 Jena, Germany.,Faculty of Biological Sciences, Friedrich Schiller University Jena, 07743 Jena, Germany
| | - José J Fernández
- Departamento de Química Orgánica, Instituto Universitario de Bio-Orgánica Antonio González (IUBO AG), Universidad de La Laguna (ULL), Avenida Astrofísico Francisco Sánchez 2, 38206 La Laguna, Tenerife, Spain
| | - María García-Altares
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Products Research and Infection Biology, Hans Knöll Institute (HKI), Adolf-Reichwein-Straße 23, 07745 Jena, Germany.,Department of Electronic Engineering, Rovira i Virgili University, 43007 Tarragona, Spain
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16
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Williams E, Bachvaroff T, Place A. A Comparison of Dinoflagellate Thiolation Domain Binding Proteins Using In Vitro and Molecular Methods. Mar Drugs 2022; 20:md20090581. [PMID: 36135770 PMCID: PMC9500876 DOI: 10.3390/md20090581] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 09/03/2022] [Accepted: 09/06/2022] [Indexed: 11/17/2022] Open
Abstract
Dinoflagellates play important roles in ecosystems as primary producers and consumers making natural products that can benefit or harm environmental and human health but are also potential therapeutics with unique chemistries. Annotations of dinoflagellate genes have been hampered by large genomes with many gene copies that reduce the reliability of transcriptomics, quantitative PCR, and targeted knockouts. This study aimed to functionally characterize dinoflagellate proteins by testing their interactions through in vitro assays. Specifically, nine Amphidinium carterae thiolation domains that scaffold natural product synthesis were substituted into an indigoidine synthesizing gene from the bacterium Streptomyces lavendulae and exposed to three A. carterae phosphopantetheinyl transferases that activate synthesis. Unsurprisingly, several of the dinoflagellate versions inhibited the ability to synthesize indigoidine despite being successfully phosphopantetheinated. However, all the transferases were able to phosphopantetheinate all the thiolation domains nearly equally, defying the canon that transferases participate in segregated processes via binding specificity. Moreover, two of the transferases were expressed during growth in alternating patterns while the final transferase was only observed as a breakdown product common to all three. The broad substrate recognition and compensatory expression shown here help explain why phosphopantetheinyl transferases are lost throughout dinoflagellate evolution without a loss in a biochemical process.
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17
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Gambierdiscus and Its Associated Toxins: A Minireview. Toxins (Basel) 2022; 14:toxins14070485. [PMID: 35878223 PMCID: PMC9324261 DOI: 10.3390/toxins14070485] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Revised: 07/11/2022] [Accepted: 07/12/2022] [Indexed: 11/17/2022] Open
Abstract
Gambierdiscus is a dinoflagellate genus widely distributed throughout tropical and subtropical regions. Some members of this genus can produce a group of potent polycyclic polyether neurotoxins responsible for ciguatera fish poisoning (CFP), one of the most significant food-borne illnesses associated with fish consumption. Ciguatoxins and maitotoxins, the two major toxins produced by Gambierdiscus, act on voltage-gated channels and TRPA1 receptors, consequently leading to poisoning and even death in both humans and animals. Over the past few decades, the occurrence and geographic distribution of CFP have undergone a significant expansion due to intensive anthropogenic activities and global climate change, which results in more human illness, a greater public health impact, and larger economic losses. The global spread of CFP has led to Gambierdiscus and its toxins being considered an environmental and human health concern worldwide. In this review, we seek to provide an overview of recent advances in the field of Gambierdiscus and its associated toxins based on the existing literature combined with re-analyses of current data. The taxonomy, phylogenetics, geographic distribution, environmental regulation, toxin detection method, toxin biosynthesis, and pharmacology and toxicology of Gambierdiscus are summarized and discussed. We also highlight future perspectives on Gambierdiscus and its associated toxins.
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18
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D’Ambrosio HK, Ganley JG, Keeler AM, Derbyshire ER. A single amino acid residue controls acyltransferase activity in a polyketide synthase from Toxoplasma gondii. iScience 2022; 25:104443. [PMID: 35874921 PMCID: PMC9301873 DOI: 10.1016/j.isci.2022.104443] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 04/12/2022] [Accepted: 05/16/2022] [Indexed: 11/17/2022] Open
Abstract
Type I polyketide synthases (PKSs) are multidomain, multimodule enzymes capable of producing complex polyketide metabolites. These modules contain an acyltransferase (AT) domain, which selects acyl-CoA substrates to be incorporated into the metabolite scaffold. Herein, we reveal the sequences of three AT domains from a polyketide synthase (TgPKS2) from the apicomplexan parasite Toxoplasma gondii. Phylogenic analysis indicates these ATs (AT1, AT2, and AT3) are distinct from domains in well-characterized microbial biosynthetic gene clusters. Biochemical investigations revealed that AT1 and AT2 hydrolyze malonyl-CoA but the terminal AT3 domain is non-functional. We further identify an "on-off switch" residue that controls activity such that a single amino acid change in AT3 confers hydrolysis activity while the analogous mutation in AT2 eliminates activity. This biochemical analysis of AT domains from an apicomplexan PKS lays the foundation for further molecular and structural studies on PKSs from T. gondii and other protists.
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Affiliation(s)
- Hannah K. D’Ambrosio
- Department of Chemistry, Duke University, 124 Science Drive, Durham, NC 27708, USA
| | - Jack G. Ganley
- Department of Chemistry, Duke University, 124 Science Drive, Durham, NC 27708, USA
| | - Aaron M. Keeler
- Department of Chemistry, Duke University, 124 Science Drive, Durham, NC 27708, USA
| | - Emily R. Derbyshire
- Department of Chemistry, Duke University, 124 Science Drive, Durham, NC 27708, USA
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, 213 Research Drive, Durham, NC 27710, USA
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19
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Kim YS, An HJ, Kim J, Jeon YJ. Current Situation of Palytoxins and Cyclic Imines in Asia-Pacific Countries: Causative Phytoplankton Species and Seafood Poisoning. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:ijerph19084921. [PMID: 35457784 PMCID: PMC9026528 DOI: 10.3390/ijerph19084921] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 04/11/2022] [Accepted: 04/13/2022] [Indexed: 02/06/2023]
Abstract
Among marine biotoxins, palytoxins (PlTXs) and cyclic imines (CIs), including spirolides, pinnatoxins, pteriatoxins, and gymnodimines, are not managed in many countries, such as the USA, European nations, and South Korea, because there are not enough poisoning cases or data for the limits on these biotoxins. In this article, we review unregulated marine biotoxins (e.g., PlTXs and CIs), their toxicity, causative phytoplankton species, and toxin extraction and detection protocols. Due to global warming, the habitat of the causative phytoplankton has expanded to the Asia-Pacific region. When ingested by humans, shellfish that accumulated toxins can cause various symptoms (muscle pain or diarrhea) and even death. There are no systematic reports on the occurrence of these toxins; however, it is important to continuously monitor causative phytoplankton and poisoning of accumulating shellfish by PlTXs and CI toxins because of the high risk of toxicity in human consumers.
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Affiliation(s)
- Young-Sang Kim
- Laboratory of Marine Bioresource Technology, Department of Marine Life Science, School of Marine Biomedical Sciences, Jeju National University, Jeju City 63243, Korea;
- Marine Science Institute, Jeju National University, Jeju City 63333, Korea
| | - Hyun-Joo An
- Asia Glycomics Reference Site, Chungnam National University, Daejeon 34134, Korea;
- Graduate School of Analytical Science and Technology, Chungnam National University, Daejeon 34134, Korea
| | - Jaeseong Kim
- Water and Eco-Bio Corporation, Kunsan National University, Kunsan 54150, Korea;
| | - You-Jin Jeon
- Laboratory of Marine Bioresource Technology, Department of Marine Life Science, School of Marine Biomedical Sciences, Jeju National University, Jeju City 63243, Korea;
- Marine Science Institute, Jeju National University, Jeju City 63333, Korea
- Correspondence: ; Tel.: +82-64-754-3475
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20
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Dinoflagellate Phosphopantetheinyl Transferase (PPTase) and Thiolation Domain Interactions Characterized Using a Modified Indigoidine Synthesizing Reporter. Microorganisms 2022; 10:microorganisms10040687. [PMID: 35456738 PMCID: PMC9027781 DOI: 10.3390/microorganisms10040687] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Revised: 03/07/2022] [Accepted: 03/14/2022] [Indexed: 02/01/2023] Open
Abstract
Photosynthetic dinoflagellates synthesize many toxic but also potential therapeutic compounds therapeutics via polyketide/non-ribosomal peptide synthesis, a common means of producing natural products in bacteria and fungi. Although canonical genes are identifiable in dinoflagellate transcriptomes, the biosynthetic pathways are obfuscated by high copy numbers and fractured synteny. This study focuses on the carrier domains that scaffold natural product synthesis (thiolation domains) and the phosphopantetheinyl transferases (PPTases) that thiolate these carriers. We replaced the thiolation domain of the indigoidine producing BpsA gene from Streptomyces lavendulae with those of three multidomain dinoflagellate transcripts and coexpressed these constructs with each of three dinoflagellate PPTases looking for specific pairings that would identify distinct pathways. Surprisingly, all three PPTases were able to activate all the thiolation domains from one transcript, although with differing levels of indigoidine produced, demonstrating an unusual lack of specificity. Unfortunately, constructs with the remaining thiolation domains produced almost no indigoidine and the thiolation domain for lipid synthesis could not be expressed in E. coli. These results combined with inconsistent protein expression for different PPTase/thiolation domain pairings present technical hurdles for future work. Despite these challenges, expression of catalytically active dinoflagellate proteins in E. coli is a novel and useful tool going forward.
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21
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Zhang S, Song W, Nothias LF, Couvillion SP, Webster N, Thomas T. Comparative metabolomic analysis reveals shared and unique chemical interactions in sponge holobionts. MICROBIOME 2022; 10:22. [PMID: 35105377 PMCID: PMC8805237 DOI: 10.1186/s40168-021-01220-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Accepted: 12/27/2021] [Indexed: 06/14/2023]
Abstract
BACKGROUND Sponges are ancient sessile metazoans, which form with their associated microbial symbionts a complex functional unit called a holobiont. Sponges are a rich source of chemical diversity; however, there is limited knowledge of which holobiont members produce certain metabolites and how they may contribute to chemical interactions. To address this issue, we applied non-targeted liquid chromatography tandem mass spectrometry (LC-MS/MS) and gas chromatography mass spectrometry (GC-MS) to either whole sponge tissue or fractionated microbial cells from six different, co-occurring sponge species. RESULTS Several metabolites were commonly found or enriched in whole sponge tissue, supporting the notion that sponge cells produce them. These include 2-methylbutyryl-carnitine, hexanoyl-carnitine and various carbohydrates, which may be potential food sources for microorganisms, as well as the antagonistic compounds hymenialdisine and eicosatrienoic acid methyl ester. Metabolites that were mostly observed or enriched in microbial cells include the antioxidant didodecyl 3,3'-thiodipropionate, the antagonistic compounds docosatetraenoic acid, and immune-suppressor phenylethylamide. This suggests that these compounds are mainly produced by the microbial members in the sponge holobiont, and are potentially either involved in inter-microbial competitions or in defenses against intruding organisms. CONCLUSIONS This study shows how different chemical functionality is compartmentalized between sponge hosts and their microbial symbionts and provides new insights into how chemical interactions underpin the function of sponge holobionts. Video abstract.
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Affiliation(s)
- Shan Zhang
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, 2052 Australia
- Centre for Marine Science and Innovation, University of New South Wales, Sydney, 2052 Australia
| | - Weizhi Song
- Centre for Marine Science and Innovation, University of New South Wales, Sydney, 2052 Australia
- School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, 2052 Australia
| | - Louis-Félix Nothias
- School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA USA
| | - Sneha P. Couvillion
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA USA
| | - Nicole Webster
- Australian Institute of Marine Science, Townsville, Australia
- Australian Centre for Ecogenomics, The University of Queensland, Brisbane, Australia
| | - Torsten Thomas
- Centre for Marine Science and Innovation, University of New South Wales, Sydney, 2052 Australia
- School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, 2052 Australia
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22
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Qiao Y, Tan X, Xu Q, Zhang Z, Xu Q, Tao L, Liu J, Zhu H, Chen C, Ye Y, Lu Y, Chen G, Qi C, Zhang Y. Asperosin A, a [4 + 2] Diels–Alder cycloaddition polyketide dimer from Aspergillus rugulosa with immunosuppressive activity. Org Chem Front 2022. [DOI: 10.1039/d1qo01767e] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
A novel homologous polyketide dimer, asperosin A (1), constructed with a unique hetero-bicycle 6/5 core skeleton featuring four continuous quaternary carbons, was isolated from a solid culture of the fungus Aspergillus rugulosa.
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Affiliation(s)
- Yuben Qiao
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, People's Republic of China
| | - Xiaosheng Tan
- Key Laboratory of Organ Transplantation, Ministry of Education; NHC Key Laboratory of Organ Transplantation; Key Laboratory of Organ Transplantation, Chinese Academy of Medical Sciences, Wuhan, China
| | - Qianqian Xu
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, People's Republic of China
| | - Zijun Zhang
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, People's Republic of China
| | - Qiaoxin Xu
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, People's Republic of China
| | - Li Tao
- Ezhou Central Hospital, Ezhou 436000, People's Republic of China
| | - Junjun Liu
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, People's Republic of China
| | - Hucheng Zhu
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, People's Republic of China
| | - Chunmei Chen
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, People's Republic of China
| | - Ying Ye
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, People's Republic of China
| | - Yuanyuan Lu
- Maternal and Child Health Hospital of Hubei Province, Tongji Medical College, Huazhong University of Science and Technology, People's Republic of China
| | - Gang Chen
- Key Laboratory of Organ Transplantation, Ministry of Education; NHC Key Laboratory of Organ Transplantation; Key Laboratory of Organ Transplantation, Chinese Academy of Medical Sciences, Wuhan, China
| | - Changxing Qi
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, People's Republic of China
| | - Yonghui Zhang
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, People's Republic of China
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23
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Jiang ZP, Sun SH, Yu Y, Mándi A, Luo JY, Yang MH, Kurtán T, Chen WH, Shen L, Wu J. Discovery of benthol A and its challenging stereochemical assignment: opening up a new window for skeletal diversity of super-carbon-chain compounds. Chem Sci 2021; 12:10197-10206. [PMID: 34447528 PMCID: PMC8336589 DOI: 10.1039/d1sc02810c] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Accepted: 06/25/2021] [Indexed: 12/28/2022] Open
Abstract
Super-carbon-chain compounds (SCCCs) are marine organic molecules featuring long polyol carbon chains with numerous stereocenters. Polyol-polyene compounds (PPCs) and ladder-frame polyethers (LFPs) are two major families. It is highly challenging to establish the absolute configurations of SCCCs. In this century, few new SCCC families have been reported. Benthol A, an aberrant SCCC, was obtained from a South China Sea benthic dinoflagellate that should belong to a new taxon. Its planar structure and absolute configuration, containing thirty-five carbon stereocenters, were unambiguously established by a combination of extensive NMR spectroscopic investigations, periodate degradation of the 1,2-diol groups, ozonolysis of the carbon-carbon double bonds, J-based configurational analysis, NOE interactions, modified Mosher's MTPA ester method, and DFT-NMR 13C chemical-shift calculations aided by DP4+ statistical analysis. Benthol A displayed potent antimalarial activity against Plasmodium falciparum 3D7 parasites. This new molecule combines extraordinary structural features, particularly eight scattered ether rings on a C72 backbone chain, which places it within a new SCCC family between PPCs and LFPs, herein termed polyol-polyether compounds. This suggestion was strongly supported by principal component analysis. The discovery of benthol A does not only provide new insights into the untapped biosynthetic potential of marine dinoflagellates, but also opens up a new window for skeletal diversity of SCCCs.
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Affiliation(s)
- Zhong-Ping Jiang
- School of Pharmaceutical Sciences, Southern Medical University 1838 Guangzhou Avenue North Guangzhou 510515 P. R. China
| | - Shi-Hao Sun
- School of Pharmaceutical Sciences, Southern Medical University 1838 Guangzhou Avenue North Guangzhou 510515 P. R. China
| | - Yi Yu
- Marine Drugs Research Center, College of Pharmacy, Jinan University 601 Huangpu Avenue West Guangzhou 510632 P. R. China
| | - Attila Mándi
- Department of Organic Chemistry, University of Debrecen PO Box 400 4002 Debrecen Hungary
| | - Jiao-Yang Luo
- Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences, Peking Union Medical College Beijing 100193 P. R. China
| | - Mei-Hua Yang
- Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences, Peking Union Medical College Beijing 100193 P. R. China
| | - Tibor Kurtán
- Department of Organic Chemistry, University of Debrecen PO Box 400 4002 Debrecen Hungary
| | - Wen-Hua Chen
- School of Biotechnology and Health Sciences, Wuyi University Jiangmen Guangdong Province 529020 P. R. China
| | - Li Shen
- Marine Drugs Research Center, College of Pharmacy, Jinan University 601 Huangpu Avenue West Guangzhou 510632 P. R. China
| | - Jun Wu
- School of Pharmaceutical Sciences, Southern Medical University 1838 Guangzhou Avenue North Guangzhou 510515 P. R. China
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Williams EP, Bachvaroff TR, Place AR. A Global Approach to Estimating the Abundance and Duplication of Polyketide Synthase Domains in Dinoflagellates. Evol Bioinform Online 2021; 17:11769343211031871. [PMID: 34345159 PMCID: PMC8283056 DOI: 10.1177/11769343211031871] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2020] [Accepted: 06/23/2021] [Indexed: 11/17/2022] Open
Abstract
Many dinoflagellate species make toxins in a myriad of different molecular configurations but the underlying chemistry in all cases is presumably via modular synthases, primarily polyketide synthases. In many organisms modular synthases occur as discrete synthetic genes or domains within a gene that act in coordination thus forming a module that produces a particular fragment of a natural product. The modules usually occur in tandem as gene clusters with a syntenic arrangement that is often predictive of the resultant structure. Dinoflagellate genomes however are notoriously complex with individual genes present in many tandem repeats and very few synthetic modules occurring as gene clusters, unlike what has been seen in bacteria and fungi. However, modular synthesis in all organisms requires a free thiol group that acts as a carrier for sequential synthesis called a thiolation domain. We scanned 47 dinoflagellate transcriptomes for 23 modular synthase domain models and compared their abundance among 10 orders of dinoflagellates as well as their co-occurrence with thiolation domains. The total count of domain types was quite large with over thirty-thousand identified, 29 000 of which were in the core dinoflagellates. Although there were no specific trends in domain abundance associated with types of toxins, there were readily observable lineage specific differences. The Gymnodiniales, makers of long polyketide toxins such as brevetoxin and karlotoxin had a high relative abundance of thiolation domains as well as multiple thiolation domains within a single transcript. Orders such as the Gonyaulacales, makers of small polyketides such as spirolides, had fewer thiolation domains but a relative increase in the number of acyl transferases. Unique to the core dinoflagellates, however, were thiolation domains occurring alongside tetratricopeptide repeats that facilitate protein-protein interactions, especially hexa and hepta-repeats, that may explain the scaffolding required for synthetic complexes capable of making large toxins. Clustering analysis for each type of domain was also used to discern possible origins of duplication for the multitude of single domain transcripts. Single domain transcripts frequently clustered with synonymous domains from multi-domain transcripts such as the BurA and ZmaK like genes as well as the multi-ketosynthase genes, sometimes with a large degree of apparent gene duplication, while fatty acid synthesis genes formed distinct clusters. Surprisingly the acyl-transferases and ketoreductases involved in fatty acid synthesis (FabD and FabG, respectively) were found in very large clusters indicating an unprecedented degree of gene duplication for these genes. These results demonstrate a complex evolutionary history of core dinoflagellate modular synthases with domain specific duplications throughout the lineage as well as clues to how large protein complexes can be assembled to synthesize the largest natural products known.
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Affiliation(s)
- Ernest P Williams
- Institute of Marine and Environmental Technologies, University of Maryland Center for Environmental Science, Baltimore, MD, USA
| | - Tsvetan R Bachvaroff
- Institute of Marine and Environmental Technologies, University of Maryland Center for Environmental Science, Baltimore, MD, USA
| | - Allen R Place
- Institute of Marine and Environmental Technologies, University of Maryland Center for Environmental Science, Baltimore, MD, USA
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Xu Q, Qiao Y, Zhang Z, Deng Y, Chen T, Tao L, Xu Q, Liu J, Sun W, Ye Y, Lu Y, Qi C, Zhang Y. New Polyketides With Anti-Inflammatory Activity From the Fungus Aspergillus rugulosa. Front Pharmacol 2021; 12:700573. [PMID: 34234683 PMCID: PMC8256160 DOI: 10.3389/fphar.2021.700573] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Accepted: 05/26/2021] [Indexed: 12/22/2022] Open
Abstract
Two new polyketide compounds, asperulosins A and B (1–2), and one new prenylated small molecule, asperulosin C (3), along with nine known compounds (4–12), were isolated and identified from a fungus Aspergillus rugulosa. Their structures were extensively elucidated via HRESIMS, 1D, and 2D NMR analysis. The absolute configurations of the new compounds were determined by the comparison of their electronic circular dichroism (ECD), calculated ECD spectra, and the detailed discussion with those in previous reports. Structurally, compounds 1 and 2 belonged to the polyketide family and were from different origins. Compound 2 was constructed by five continuous quaternary carbon atoms, which occur rarely in natural products. All of the isolates were evaluated for anti-inflammatory activity against the production of nitric oxide (NO) in lipopolysaccharide (LPS)-induced RAW264.7 cells. Among those, compounds 1 and 5 showed a significant inhibitory effect on NO production with IC50 values of 1.49 ± 0.31 and 3.41 ± 0.85 μM, respectively. Additionally, compounds 1 and 5 markedly increased the secretion of anti-inflammatory cytokine IL10 while suppressing the secretion of pro-inflammatory cytokines IL6, TNF-α, IFN-γ, MCP-1, and IL12. Besides, 1 and 5 inhibited the transcription level of pro-inflammatory macrophage markers IL6, IL1β, and TNF-α while remarkably elevating the anti-inflammatory factor IL10 and M2 macrophage markers ARG1 and CD206. Moreover, 1 and 5 restrained the expression and nuclear translocation of NF-κB, as well as its downstream signaling proteins COX-2 and iNOS. All these results suggest that 1 and 5 have potential as anti-inflammatory agents, with better or comparable activities than those of the positive control, dexamethasone.
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Affiliation(s)
- Qianqian Xu
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yuben Qiao
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Zijun Zhang
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yanfang Deng
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Tianqi Chen
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Li Tao
- Ezhou Central Hospital, Ezhou, China
| | - Qiaoxin Xu
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Junjun Liu
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Weiguang Sun
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Ying Ye
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yuanyuan Lu
- Maternal and Child Health Hospital of Hubei Province, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Changxing Qi
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yonghui Zhang
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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Abstract
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A nonthermodynamic array of four skipped methylene substituents on the hydrophobic tail
renders limaol, a C40-polyketide of marine origin, unique in structural terms. This
conspicuous segment was assembled by a two-directional approach and finally coupled to
the polyether domain by an allyl/alkenyl Stille reaction under neutral conditions. The
core region itself was prepared via a 3,3′-dibromo-BINOL-catalyzed asymmetric
propargylation, a gold-catalyzed spirocyclization, and introduction of the southern
sector via substrate-controlled allylation as the key steps.
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Affiliation(s)
- Stephan N Hess
- Max-Planck-Institut für Kohlenforschung, 45470 Mülheim/Ruhr, Germany
| | - Xiaobin Mo
- Max-Planck-Institut für Kohlenforschung, 45470 Mülheim/Ruhr, Germany
| | - Conny Wirtz
- Max-Planck-Institut für Kohlenforschung, 45470 Mülheim/Ruhr, Germany
| | - Alois Fürstner
- Max-Planck-Institut für Kohlenforschung, 45470 Mülheim/Ruhr, Germany
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Walker PD, Weir ANM, Willis CL, Crump MP. Polyketide β-branching: diversity, mechanism and selectivity. Nat Prod Rep 2021; 38:723-756. [PMID: 33057534 DOI: 10.1039/d0np00045k] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Covering: 2008 to August 2020 Polyketides are a family of natural products constructed from simple building blocks to generate a diverse range of often complex chemical structures with biological activities of both pharmaceutical and agrochemical importance. Their biosynthesis is controlled by polyketide synthases (PKSs) which catalyse the condensation of thioesters to assemble a functionalised linear carbon chain. Alkyl-branches may be installed at the nucleophilic α- or electrophilic β-carbon of the growing chain. Polyketide β-branching is a fascinating biosynthetic modification that allows for the conversion of a β-ketone into a β-alkyl group or functionalised side-chain. The overall transformation is catalysed by a multi-protein 3-hydroxy-3-methylglutaryl synthase (HMGS) cassette and is reminiscent of the mevalonate pathway in terpene biosynthesis. The first step most commonly involves the aldol addition of acetate to the electrophilic carbon of the β-ketothioester catalysed by a 3-hydroxy-3-methylglutaryl synthase (HMGS). Subsequent dehydration and decarboxylation selectively generates either α,β- or β,γ-unsaturated β-alkyl branches which may be further modified. This review covers 2008 to August 2020 and summarises the diversity of β-branch incorporation and the mechanistic details of each catalytic step. This is extended to discussion of polyketides containing multiple β-branches and the selectivity exerted by the PKS to ensure β-branching fidelity. Finally, the application of HMGS in data mining, additional β-branching mechanisms and current knowledge of the role of β-branches in this important class of biologically active natural products is discussed.
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Affiliation(s)
- P D Walker
- Institute of Metabolism and Systems Research, College of Medical and Dental Sciences, University of Birmingham, Birmingham, B15 2TT, UK
| | - A N M Weir
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK.
| | - C L Willis
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK.
| | - M P Crump
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK.
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Satake M, Iguchi K, Watanabe R, Uchida H, Nagai H. Aplysiadione and aplysiaenal: Truncated biosynthetic intermediates of aplysiatoxins from a cyanobacterium. RESULTS IN CHEMISTRY 2021. [DOI: 10.1016/j.rechem.2021.100206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Wu J, Jiang ZP, Yan RJ, Sun SH, Yu Y, Shen L. Gibbosolide A, a highly functionalized 20-membered macrolide with a terminal cis-fused 2-methylhexahydro-2 H-furo[3,2- b]pyran motif: insights into late-stage cyclization of marine macrolides. Org Chem Front 2021. [DOI: 10.1039/d1qo01038g] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The planar structure and absolute configuration of a sailboat-shaped marine macrolide, featuring twelve carbon stereocenters and a cis-fused ether ring juncture, were unambiguously established by a combined approach of chemistry and spectroscopy.
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Affiliation(s)
- Jun Wu
- School of Pharmaceutical Sciences, Southern Medical University, 1838 Guangzhou Avenue North, Guangzhou 510515, PR China
| | - Zhong-Ping Jiang
- School of Pharmaceutical Sciences, Southern Medical University, 1838 Guangzhou Avenue North, Guangzhou 510515, PR China
| | - Ren-Jie Yan
- School of Pharmaceutical Sciences, Southern Medical University, 1838 Guangzhou Avenue North, Guangzhou 510515, PR China
| | - Shi-Hao Sun
- School of Pharmaceutical Sciences, Southern Medical University, 1838 Guangzhou Avenue North, Guangzhou 510515, PR China
| | - Yi Yu
- Marine Drugs Research Center, College of Pharmacy, Jinan University, 601 Huangpu Avenue West, Guangzhou 510632, PR China
| | - Li Shen
- Marine Drugs Research Center, College of Pharmacy, Jinan University, 601 Huangpu Avenue West, Guangzhou 510632, PR China
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30
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Biosynthesis of marine toxins. Curr Opin Chem Biol 2020; 59:119-129. [DOI: 10.1016/j.cbpa.2020.06.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 06/21/2020] [Accepted: 06/23/2020] [Indexed: 12/18/2022]
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Nieva JA, Krock B, Tillmann U, Tebben J, Zurhelle C, Bickmeyer U. Gymnodimine A and 13-desMethyl Spirolide C Alter Intracellular Calcium Levels via Acetylcholine Receptors. Toxins (Basel) 2020; 12:toxins12120751. [PMID: 33261221 PMCID: PMC7760841 DOI: 10.3390/toxins12120751] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 11/23/2020] [Accepted: 11/26/2020] [Indexed: 11/18/2022] Open
Abstract
Gymnodimines and spirolides are cyclic imine phycotoxins and known antagonists of nicotinic acetylcholine receptors (nAChRs). We investigated the effect of gymnodimine A (GYM A) and 13-desmethyl spirolide C (SPX 1) from Alexandrium ostenfeldii on rat pheochromocytoma (PC12) cells by monitoring intracellular calcium levels ([Ca]i). Using whole cells, the presence of 0.5 µM of GYM A or SPX 1 induced an increase in [Ca]i mediated by acetylcholine receptors (AChRs) and inhibited further activation of AChRs by acetylcholine (ACh). To differentiate the effects of GYM A or SPX 1, the toxins were applied to cells with pharmacologically isolated nAChRs and muscarinic AChRs (mAChRs) as mediated by the addition of atropine and tubocurarine, respectively. GYM A and SPX 1 activated nAChRs and inhibited the further activation of nAChRs by ACh, indicating that both toxins mimicked the activity of ACh. Regarding mAChRs, a differential response was observed between the two toxins. Only GYM A activated mAChRs, resulting in elevated [Ca]i, but both toxins prevented a subsequent activation by ACh. The absence of the triketal ring system in GYM A may provide the basis for a selective activation of mAChRs. GYM A and SPX 1 induced no changes in [Ca]i when nAChRs and mAChRs were inhibited simultaneously, indicating that both toxins target AChRs.
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A Polyol-Polyol Super-Carbon-Chain Compound Containing Thirty-Six Carbon Stereocenters from the Dinoflagellate Amphidinium gibbosum: Absolute Configuration and Multi-Segment Modification. Mar Drugs 2020; 18:md18120590. [PMID: 33255887 PMCID: PMC7759953 DOI: 10.3390/md18120590] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Revised: 11/21/2020] [Accepted: 11/22/2020] [Indexed: 12/24/2022] Open
Abstract
A super-carbon-chain compound, named gibbosol C, featuring a polyoxygenated C70-linear-carbon-chain backbone encompassing two acyclic polyol chains, was obtained from the South China Sea dinoflagellate Amphidinium gibbosum. Its planar structure was elucidated by extensive NMR investigations, whereas its absolute configurations, featuring the presence of 36 carbon stereocenters and 30 hydroxy groups, were successfully established by comparison of NMR data of the ozonolyzed products with those of gibbosol A, combined with J-based configuration analysis, Kishi’s universal NMR database, and the modified Mosher’s MTPA ester method. Multi-segment modification was revealed as the smart biosynthetic strategy for the dinoflagellate to create remarkable super-carbon-chain compounds with structural diversity.
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Beedessee G, Kubota T, Arimoto A, Nishitsuji K, Waller RF, Hisata K, Yamasaki S, Satoh N, Kobayashi J, Shoguchi E. Integrated omics unveil the secondary metabolic landscape of a basal dinoflagellate. BMC Biol 2020; 18:139. [PMID: 33050904 PMCID: PMC7557087 DOI: 10.1186/s12915-020-00873-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Accepted: 09/18/2020] [Indexed: 01/04/2023] Open
Abstract
BACKGROUND Some dinoflagellates cause harmful algal blooms, releasing toxic secondary metabolites, to the detriment of marine ecosystems and human health. Our understanding of dinoflagellate toxin biosynthesis has been hampered by their unusually large genomes. To overcome this challenge, for the first time, we sequenced the genome, microRNAs, and mRNA isoforms of a basal dinoflagellate, Amphidinium gibbosum, and employed an integrated omics approach to understand its secondary metabolite biosynthesis. RESULTS We assembled the ~ 6.4-Gb A. gibbosum genome, and by probing decoded dinoflagellate genomes and transcriptomes, we identified the non-ribosomal peptide synthetase adenylation domain as essential for generation of specialized metabolites. Upon starving the cells of phosphate and nitrogen, we observed pronounced shifts in metabolite biosynthesis, suggestive of post-transcriptional regulation by microRNAs. Using Iso-Seq and RNA-seq data, we found that alternative splicing and polycistronic expression generate different transcripts for secondary metabolism. CONCLUSIONS Our genomic findings suggest intricate integration of various metabolic enzymes that function iteratively to synthesize metabolites, providing mechanistic insights into how dinoflagellates synthesize secondary metabolites, depending upon nutrient availability. This study provides insights into toxin production associated with dinoflagellate blooms. The genome of this basal dinoflagellate provides important clues about dinoflagellate evolution and overcomes the large genome size, which has been a challenge previously.
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Affiliation(s)
- Girish Beedessee
- Marine Genomics Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa, 904-0495, Japan.
- Present address: Department of Biochemistry, University of Cambridge, Cambridge, CB2 1QW, UK.
| | - Takaaki Kubota
- Showa Pharmaceutical University, 3-3165 Higashi-Tamagawagakuen, Machida, Tokyo, 194-8543, Japan
| | - Asuka Arimoto
- Marine Genomics Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa, 904-0495, Japan
- Marine Biological Laboratory, Graduate School of Integrated Sciences for Life, Hiroshima University, Onomichi, Hiroshima, 722-0073, Japan
| | - Koki Nishitsuji
- Marine Genomics Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa, 904-0495, Japan
| | - Ross F Waller
- Department of Biochemistry, University of Cambridge, Cambridge, CB2 1QW, UK
| | - Kanako Hisata
- Marine Genomics Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa, 904-0495, Japan
| | - Shinichi Yamasaki
- DNA Sequencing Section, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa, 904-0495, Japan
| | - Noriyuki Satoh
- Marine Genomics Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa, 904-0495, Japan
| | - Jun'ichi Kobayashi
- Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo, 060-0812, Japan
| | - Eiichi Shoguchi
- Marine Genomics Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa, 904-0495, Japan
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Mass Spectrometry-Based Characterization of New Spirolides from Alexandrium ostenfeldii (Dinophyceae). Mar Drugs 2020; 18:md18100505. [PMID: 33023163 PMCID: PMC7599687 DOI: 10.3390/md18100505] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 09/23/2020] [Accepted: 09/28/2020] [Indexed: 11/23/2022] Open
Abstract
Spirolides belong to a group of marine phycotoxins produced by the marine planktonic dinophyte Alexandrium ostenfeldii. Composed of an imine moiety and a spiroketal ring system within a macrocylcle, spirolides are highly diverse with toxin types that vary among different strains. This study aims to characterize the spirolides from clonal A. ostenfeldii strains collected from The Netherlands, Greenland and Norway by mass spectral techniques. The structural characterization of unknown spirolides as inferred from high-resolution mass spectrometry (HR-MS) and collision induced dissociation (CID) spectra revealed the presence of nine novel spirolides that have the pseudo-molecular ions m/z 670 (1), m/z 666 (2), m/z 696 (3), m/z 678 (4), m/z 694 (5), m/z 708 (6), m/z 720 (7), m/z 722 (8) and m/z 738 (9). Of the nine new spirolides proposed in this study, compound 1 was suggested to have a truncated side chain in lieu of the commonly observed butenolide ring in spirolides. Moreover, there is indication that compound 5 might belong to new spirolide subclasses with a trispiroketal ring configuration having a 6:5:6 trispiroketal ring system. On the other hand, the other compounds were proposed as C- and G-type SPX, respectively. Compound 7 is proposed as the first G-type SPX with a 10-hydroxylation as usually observed in C-type SPX. This mass spectrometry-based study thus demonstrates that structural variability of spirolides is larger than previously known and does not only include the presence or absence of certain functional groups but also involves the triketal ring system.
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Highlights of marine natural products having parallel scaffolds found from marine-derived bacteria, sponges, and tunicates. J Antibiot (Tokyo) 2020; 73:504-525. [PMID: 32507851 PMCID: PMC7276339 DOI: 10.1038/s41429-020-0330-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2020] [Revised: 05/16/2020] [Accepted: 05/18/2020] [Indexed: 12/11/2022]
Abstract
Marine-derived bacteria are a prolific source of a wide range of structurally diverse natural products. This review, dedicated to Professor William Fenical, begins by showcasing many seminal discoveries made at the University of California San Diego from marine-derived actinomycetes. Discussed early on is the 20-year journey of discovery and advancement of the seminal actinomycetes natural product salinosporamide A into Phase III anticancer clinical trials. There are many fascinating parallels discussed that were gleaned from the comparative literature of marine sponge, tunicate, and bacteria-derived natural products. Identifying bacterial biosynthetic machinery housed in sponge and tunicate holobionts through both culture-independent and culture-dependent approaches is another important and expanding subject that is analyzed. Work reviewed herein also evaluates the hypotheses that many marine invertebrate-derived natural products are biosynthesised by associated or symbiotic bacteria. The insights and outcomes from metagenomic sequencing and synthetic biology to expand molecule discovery continue to provide exciting outcomes and they are predicted to be the source of the next generation of novel marine natural product chemical scaffolds.
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Wu Z, Luo H, Yu L, Lee WH, Li L, Mak YL, Lin S, Lam PKS. Characterizing ciguatoxin (CTX)- and Non-CTX-producing strains of Gambierdiscus balechii using comparative transcriptomics. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 717:137184. [PMID: 32084685 DOI: 10.1016/j.scitotenv.2020.137184] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 01/28/2020] [Accepted: 02/06/2020] [Indexed: 06/10/2023]
Abstract
Gambierdiscus spp. can produce the polyketide compound, ciguatoxin (CTX), and are hence responsible for ciguatera fish poisoning (CFP). Studying the molecular mechanism that regulates CTX production is crucial for understanding the environmental trigger of CTX as well as for better informing fishery management. Commonly, polyketide synthases are important for polyketide synthesis; however, no gene has been confirmatively assigned to CTX production. Here, suppression subtractive hybridization (SSH) and transcriptome sequencing (RNA-Seq) were used to compare a CTX-producing strain with a non-CTX-producing strain. Using both methods, a total of 52 polyketide synthase (PKS) genes were identified to be up-regulated in the CTX-producing G. balechii, including transcripts encoding single-domain PKSs as well as transcripts encoding multi-domain PKSs. Using reverse transcription quantitative PCR, the expression of these genes in the CTX-producing strain and in nitrogen-limited cultures of the strain was further documented. These data suggest that PKSs are likely involved in polyketide synthesis and potentially in CTX synthesis in this dinoflagellate species. Our study provides the candidate biomarkers for the detection of CTXs or CFP in waters or any other organisms as well as a valuable genomic resource for the research on Gambierdiscus and other dinoflagellates.
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Affiliation(s)
- Zhen Wu
- State Key Laboratory of Marine Pollution, City University of Hong Kong, Hong Kong, China; Department of Chemistry, City University of Hong Kong, Hong Kong, China
| | - Hao Luo
- State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen, China
| | - Liying Yu
- State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen, China
| | - Wai Hin Lee
- State Key Laboratory of Marine Pollution, City University of Hong Kong, Hong Kong, China; Department of Biomedical Sciences, City University of Hong Kong, Hong Kong, China
| | - Ling Li
- State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen, China
| | - Yim Ling Mak
- State Key Laboratory of Marine Pollution, City University of Hong Kong, Hong Kong, China; Shenzhen Key Laboratory for the Sustainable Use of Marine Biodiversity, Research Centre for the Oceans and Human Health, City University of Hong Kong Shenzhen Research Institute, Shenzhen, China
| | - Senjie Lin
- State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen, China; Department of Marine Sciences, University of Connecticut, Groton, CT, USA.
| | - Paul K S Lam
- State Key Laboratory of Marine Pollution, City University of Hong Kong, Hong Kong, China; Department of Chemistry, City University of Hong Kong, Hong Kong, China; Shenzhen Key Laboratory for the Sustainable Use of Marine Biodiversity, Research Centre for the Oceans and Human Health, City University of Hong Kong Shenzhen Research Institute, Shenzhen, China
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Ganley JG, Derbyshire ER. Linking Genes to Molecules in Eukaryotic Sources: An Endeavor to Expand Our Biosynthetic Repertoire. Molecules 2020; 25:E625. [PMID: 32023950 PMCID: PMC7036892 DOI: 10.3390/molecules25030625] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Revised: 01/23/2020] [Accepted: 01/30/2020] [Indexed: 02/06/2023] Open
Abstract
The discovery of natural products continues to interest chemists and biologists for their utility in medicine as well as facilitating our understanding of signaling, pathogenesis, and evolution. Despite an attenuation in the discovery rate of new molecules, the current genomics and transcriptomics revolution has illuminated the untapped biosynthetic potential of many diverse organisms. Today, natural product discovery can be driven by biosynthetic gene cluster (BGC) analysis, which is capable of predicting enzymes that catalyze novel reactions and organisms that synthesize new chemical structures. This approach has been particularly effective in mining bacterial and fungal genomes where it has facilitated the discovery of new molecules, increased the understanding of metabolite assembly, and in some instances uncovered enzymes with intriguing synthetic utility. While relatively less is known about the biosynthetic potential of non-fungal eukaryotes, there is compelling evidence to suggest many encode biosynthetic enzymes that produce molecules with unique bioactivities. In this review, we highlight how the advances in genomics and transcriptomics have aided natural product discovery in sources from eukaryotic lineages. We summarize work that has successfully connected genes to previously identified molecules and how advancing these techniques can lead to genetics-guided discovery of novel chemical structures and reactions distributed throughout the tree of life. Ultimately, we discuss the advantage of increasing the known biosynthetic space to ease access to complex natural and non-natural small molecules.
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Affiliation(s)
- Jack G Ganley
- Department of Chemistry, Duke University, 124 Science Drive, Durham, NC 27708-0346, USA
| | - Emily R Derbyshire
- Department of Chemistry, Duke University, 124 Science Drive, Durham, NC 27708-0346, USA
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, 213 Research Drive, Durham, NC 27710, USA
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Niu Z, Xu W, Na J, Lv Z, Zhang Y. How long-term exposure of environmentally relevant antibiotics may stimulate the growth of Prorocentrum lima: A probable positive factor for red tides. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2019; 255:113149. [PMID: 31522007 DOI: 10.1016/j.envpol.2019.113149] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Revised: 07/29/2019] [Accepted: 08/30/2019] [Indexed: 06/10/2023]
Abstract
Antibiotics have been widely detected in the ocean and have various impacts on the environment, while knowledge of their chronic influence on phytoplankton, especially red tide algae, is still limited. Dinoflagellates and green algae are common phytoplankton in marine ecosystems. The former is the main red tide algae, and the latter is an important primary producer. We investigated the long-term responses of two representative algae, Prorocentrum lima and Chlorella sp., to two common antibiotics (sulfamethoxazole (SMX) and norfloxacin (NFX)) at environmentally relevant levels (10 and 100 ng/L) during simulated natural conditions. The cell density and activities of three antioxidant enzymes (superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD)) were analyzed. The results showed that the influence of each antibiotic on Chlorella sp. was not significant (p > 0.05) during the first 10 days, but the influence of the antibiotics later began to show significant inhibition (p < 0.05) compared with the control group, especially during mixed exposure. P. lima was not inhibited, but its cell density increased. SMX had a superior stimulation effect on P. lima. The three enzymes activities of P. lima increased, and the antioxidant mechanism was not seriously impacted. However, for Chlorella sp., the activity of SOD increased while the activities of CAT and POD decreased, suggesting that this algae's antioxidant system was unbalanced due to oxidative stress. Based on our results, the growth of P. lima was different from green algae Chlorella sp. as well as other inhibited marine algae (such as diatom, golden algae) studied in previous studies. Therefore, as a typical pollutant in the ocean, antibiotics may play a positive role in the bloom of dinoflagellate red tides.
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Affiliation(s)
- Zhiguang Niu
- School of Marine Science and Technology, Tianjin University, Tianjin 300072, China
| | - Wei'an Xu
- School of Marine Science and Technology, Tianjin University, Tianjin 300072, China
| | - Jing Na
- School of Marine Science and Technology, Tianjin University, Tianjin 300072, China
| | - Zhiwei Lv
- School of Marine Science and Technology, Tianjin University, Tianjin 300072, China
| | - Ying Zhang
- MOE Key Laboratory of Pollution Processes and Environmental Criteria/Tianjin Key Laboratory of Environmental Technology for Complex Trans-Media Pollution, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China.
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Wan X, Yao G, Liu Y, Chen J, Jiang H. Research Progress in the Biosynthetic Mechanisms of Marine Polyether Toxins. Mar Drugs 2019; 17:E594. [PMID: 31652489 PMCID: PMC6835853 DOI: 10.3390/md17100594] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Revised: 10/17/2019] [Accepted: 10/18/2019] [Indexed: 12/28/2022] Open
Abstract
Marine polyether toxins, mainly produced by marine dinoflagellates, are novel, complex, and diverse natural products with extensive toxicological and pharmacological effects. Owing to their harmful effects during outbreaks of marine red tides, as well as their potential value for the development of new drugs, marine polyether toxins have been extensively studied, in terms of toxicology, pharmacology, detection, and analysis, structural identification, as well as their biosynthetic mechanisms. Although the biosynthetic mechanisms of marine polyether toxins are still unclear, certain progress has been made. In this review, research progress and current knowledge on the biosynthetic mechanisms of polyether toxins are summarized, including the mechanisms of carbon skeleton deletion, pendant alkylation, and polyether ring formation, along with providing a summary of mined biosynthesis-related genes. Finally, future research directions and applications of marine polyether toxins are discussed.
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Affiliation(s)
- Xiukun Wan
- State Key Laboratory of NBC Protection for Civilian, Beijing 102205, China.
| | - Ge Yao
- State Key Laboratory of NBC Protection for Civilian, Beijing 102205, China.
| | - Yanli Liu
- State Key Laboratory of NBC Protection for Civilian, Beijing 102205, China.
| | - Jisheng Chen
- State Key Laboratory of NBC Protection for Civilian, Beijing 102205, China.
| | - Hui Jiang
- State Key Laboratory of NBC Protection for Civilian, Beijing 102205, China.
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40
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Binzer SB, Svenssen DK, Daugbjerg N, Alves-de-Souza C, Pinto E, Hansen PJ, Larsen TO, Varga E. A-, B- and C-type prymnesins are clade specific compounds and chemotaxonomic markers in Prymnesium parvum. HARMFUL ALGAE 2019; 81:10-17. [PMID: 30638493 DOI: 10.1016/j.hal.2018.11.010] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Revised: 11/14/2018] [Accepted: 11/16/2018] [Indexed: 05/11/2023]
Abstract
Harmful blooms formed by planktonic microalgae (HABs) in both freshwater and coastal waters regularly lead to severe mortalities of fish and invertebrates causing substantial economic losses of marine products worldwide. The mixotrophic haptophyte Prymnesium parvum is one of the most important microalgae associated with fish kills. Here 26 strains of P. parvum with a wide geographical distribution were screened for the production of prymnesins, the suspected causative allelochemical toxins. All investigated strains produced prymnesins, indicating that the toxins play an important role for the organism. The prymnesins can be classified into three types based on the length of the carbon backbone of the compound and each algal strain produced only one of these types. Biogeographical mapping of the prymnesin distribution indicated a global distribution of each type. In addition, phylogenetic analyses based on internal transcribed spacer (ITS) sequences revealed monophyletic origin of all prymnesin types and clades could therefore be defined based on the toxic compound. It might be that evolution of new species within the P. parvum species complex is driven by changes in toxin type or that they are a result of it. Such a correlation between chemotype and phylotype has never been documented before for a harmful microalga. Chemotaxonomy and ITS-type classification may thus be used to further delimit the P. parvum species complex.
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Affiliation(s)
- Sofie Bjørnholt Binzer
- Marine Biological Section, Department of Biology, University of Copenhagen, Strandpromenaden 5, 3000, Helsingør, Denmark
| | - Daniel Killerup Svenssen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads 221, 2800, Kgs. Lyngby, Denmark
| | - Niels Daugbjerg
- Marine Biological Section, Department of Biology, University of Copenhagen, Universitetsparken 4, 2200, Copenhagen K, Denmark.
| | - Catharina Alves-de-Souza
- Algal Resources Collection, MARBIONC at CREST Research Park, University of North Carolina Wilmington, 5600 Marvin K. Moss Ln, Wilmington, NC, 28409, USA; Laboratório de Ficologia, Departamento de Botânica, Museu Nacional/Universidade Federal do Rio de Janeiro, Quinta da Boa Vista S/N, São Cristóvão, Rio de Janeiro, RJ, 20940-040, Brazil
| | - Ernani Pinto
- School of Pharmaceutical Sciences, University of Sao Paulo, Av. Prof Lineu Prestes 580, 05508-000, São Paulo, SP, Brazil
| | - Per Juel Hansen
- Marine Biological Section, Department of Biology, University of Copenhagen, Strandpromenaden 5, 3000, Helsingør, Denmark.
| | - Thomas Ostenfeld Larsen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads 221, 2800, Kgs. Lyngby, Denmark.
| | - Elisabeth Varga
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads 221, 2800, Kgs. Lyngby, Denmark
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Kurimoto SI, Iinuma Y, Kobayashi J, Kubota T. Symbiodinolactone A, a new 12-membered macrolide from symbiotic marine dinoflagellate Symbiodinium sp. Tetrahedron Lett 2018. [DOI: 10.1016/j.tetlet.2018.11.018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Identification of Novel Gymnodimines and Spirolides from the Marine Dinoflagellate Alexandrium ostenfeldii. Mar Drugs 2018; 16:md16110446. [PMID: 30441860 PMCID: PMC6266918 DOI: 10.3390/md16110446] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Revised: 10/26/2018] [Accepted: 11/05/2018] [Indexed: 01/08/2023] Open
Abstract
Cyclic imine toxins are neurotoxic, macrocyclic compounds produced by marine dinoflagellates. Mass spectrometric screenings of extracts from natural plankton assemblages revealed a high chemical diversity among this toxin class, yet only few toxins are structurally known. Here we report the structural characterization of four novel cyclic-imine toxins (two gymnodimines (GYMs) and two spirolides (SPXs)) from cultures of Alexandrium ostenfeldii. A GYM with m/z 510 (1) was identified as 16-desmethylGYM D. A GYM with m/z 526 was identified as the hydroxylated degradation product of (1) with an exocyclic methylene at C-17 and an allylic hydroxyl group at C-18. This compound was named GYM E (2). We further identified a SPX with m/z 694 as 20-hydroxy-13,19-didesmethylSPX C (10) and a SPX with m/z 696 as 20-hydroxy-13,19-didesmethylSPX D (11). This is the first report of GYMs without a methyl group at ring D and SPXs with hydroxyl groups at position C-20. These compounds can be conceived as derivatives of the same nascent polyketide chain, supporting the hypothesis that GYMs and SPXs are produced through common biosynthetic genes. Both novel GYMs 1 and 2 were detected in significant amounts in extracts from natural plankton assemblages (1: 447 pg; 2: 1250 pg; 11: 40 pg per mL filtered seawater respectively).
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Heimerl N, Hommel E, Westermann M, Meichsner D, Lohr M, Hertweck C, Grossman AR, Mittag M, Sasso S. A giant type I polyketide synthase participates in zygospore maturation in Chlamydomonas reinhardtii. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2018; 95:268-281. [PMID: 29729034 DOI: 10.1111/tpj.13948] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Revised: 04/14/2018] [Accepted: 04/23/2018] [Indexed: 06/08/2023]
Abstract
Polyketide synthases (PKSs) occur in many bacteria, fungi and plants. They are highly versatile enzymes involved in the biosynthesis of a large variety of compounds including antimicrobial agents, polymers associated with bacterial cell walls and plant pigments. While harmful algae are known to produce polyketide toxins, sequences of the genomes of non-toxic algae, including those of many green algal species, have surprisingly revealed the presence of genes encoding type I PKSs. The genome of the model alga Chlamydomonas reinhardtii (Chlorophyta) contains a single type I PKS gene, designated PKS1 (Cre10.g449750), which encodes a giant PKS with a predicted mass of 2.3 MDa. Here, we show that PKS1 is induced in 2-day-old zygotes and is required for their development into zygospores, the dormant stage of the zygote. Wild-type zygospores contain knob-like structures (~50 nm diameter) that form at the cell surface and develop a central cell wall layer; both of these structures are absent from homozygous pks1 mutants. Additionally, in contrast to wild-type zygotes, chlorophyll degradation is delayed in homozygous pks1 mutant zygotes, indicating a disruption in zygospore development. In agreement with the role of the PKS in the formation of the highly resistant zygospore wall, mutant zygotes have lost the formidable desiccation tolerance of wild-type zygotes. Together, our results represent functional analyses of a PKS mutant in a photosynthetic eukaryotic microorganism, revealing a central function for polyketides in the sexual cycle and survival under stressful environmental conditions.
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Affiliation(s)
- Natalie Heimerl
- Matthias Schleiden Institute of Genetics, Bioinformatics and Molecular Botany, Friedrich Schiller University, Jena, Germany
| | - Elisabeth Hommel
- Matthias Schleiden Institute of Genetics, Bioinformatics and Molecular Botany, Friedrich Schiller University, Jena, Germany
| | | | - Doreen Meichsner
- Matthias Schleiden Institute of Genetics, Bioinformatics and Molecular Botany, Friedrich Schiller University, Jena, Germany
| | - Martin Lohr
- Institute of Molecular Physiology, Plant Biochemistry, Johannes Gutenberg University, Mainz, Germany
| | - Christian Hertweck
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Jena, Germany
- Friedrich Schiller University, Jena, Germany
| | | | - Maria Mittag
- Matthias Schleiden Institute of Genetics, Bioinformatics and Molecular Botany, Friedrich Schiller University, Jena, Germany
| | - Severin Sasso
- Matthias Schleiden Institute of Genetics, Bioinformatics and Molecular Botany, Friedrich Schiller University, Jena, Germany
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Jena, Germany
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44
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Ogawara H. Comparison of Strategies to Overcome Drug Resistance: Learning from Various Kingdoms. Molecules 2018; 23:E1476. [PMID: 29912169 PMCID: PMC6100412 DOI: 10.3390/molecules23061476] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Revised: 06/13/2018] [Accepted: 06/15/2018] [Indexed: 11/16/2022] Open
Abstract
Drug resistance, especially antibiotic resistance, is a growing threat to human health. To overcome this problem, it is significant to know precisely the mechanisms of drug resistance and/or self-resistance in various kingdoms, from bacteria through plants to animals, once more. This review compares the molecular mechanisms of the resistance against phycotoxins, toxins from marine and terrestrial animals, plants and fungi, and antibiotics. The results reveal that each kingdom possesses the characteristic features. The main mechanisms in each kingdom are transporters/efflux pumps in phycotoxins, mutation and modification of targets and sequestration in marine and terrestrial animal toxins, ABC transporters and sequestration in plant toxins, transporters in fungal toxins, and various or mixed mechanisms in antibiotics. Antibiotic producers in particular make tremendous efforts for avoiding suicide, and are more flexible and adaptable to the changes of environments. With these features in mind, potential alternative strategies to overcome these resistance problems are discussed. This paper will provide clues for solving the issues of drug resistance.
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Affiliation(s)
- Hiroshi Ogawara
- HO Bio Institute, Yushima-2, Bunkyo-ku, Tokyo 113-0034, Japan.
- Department of Biochemistry, Meiji Pharmaceutical University, Noshio-2, Kiyose, Tokyo 204-8588, Japan.
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45
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He Y, Wang B, Chen W, Cox RJ, He J, Chen F. Recent advances in reconstructing microbial secondary metabolites biosynthesis in Aspergillus spp. Biotechnol Adv 2018; 36:739-783. [DOI: 10.1016/j.biotechadv.2018.02.001] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Revised: 01/30/2018] [Accepted: 02/01/2018] [Indexed: 11/28/2022]
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46
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Wang L, Wu F, Jia X, Xu Z, Guo Y, Ye T. Studies toward the Synthesis of Iriomoteolide-2a: Construction of the C(6)-C(28) Fragment. Org Lett 2018; 20:2213-2215. [PMID: 29633846 DOI: 10.1021/acs.orglett.8b00542] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The synthesis of an appropriately functionalized advanced C(6-28) fragment (3) of the marine macrolide iriomoteolide-2a (1) has been achieved in a highly efficient manner. The C(6)-C(18) fragment of 1 is prepared via a radical cyclization of a vinyl ether intermediate and palladium-promoted hydrostannylation/iodination. Paterson aldol reaction and Peterson olefination are used to construct the C(19)-C(28) fragment. The union of the C(6)-C(18) and C(19)-C(28) fragments is accomplished via a Suzuki-Miyaura coupling reaction.
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Affiliation(s)
- Lushun Wang
- State Key Laboratory of Chemical Oncogenomics, Key Laboratory of Chemical Genomics , Peking University Shenzhen Graduate School , Xili , Nanshan District, Shenzhen 518055 , China
| | - Fusong Wu
- State Key Laboratory of Chemical Oncogenomics, Key Laboratory of Chemical Genomics , Peking University Shenzhen Graduate School , Xili , Nanshan District, Shenzhen 518055 , China
| | - Xuelei Jia
- State Key Laboratory of Chemical Oncogenomics, Key Laboratory of Chemical Genomics , Peking University Shenzhen Graduate School , Xili , Nanshan District, Shenzhen 518055 , China
| | - Zhengshuang Xu
- State Key Laboratory of Chemical Oncogenomics, Key Laboratory of Chemical Genomics , Peking University Shenzhen Graduate School , Xili , Nanshan District, Shenzhen 518055 , China
| | - Yian Guo
- State Key Laboratory of Chemical Oncogenomics, Key Laboratory of Chemical Genomics , Peking University Shenzhen Graduate School , Xili , Nanshan District, Shenzhen 518055 , China
| | - Tao Ye
- State Key Laboratory of Chemical Oncogenomics, Key Laboratory of Chemical Genomics , Peking University Shenzhen Graduate School , Xili , Nanshan District, Shenzhen 518055 , China
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47
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Van Dolah FM, Kohli GS, Morey JS, Murray SA. Both modular and single-domain Type I polyketide synthases are expressed in the brevetoxin-producing dinoflagellate, Karenia brevis (Dinophyceae). JOURNAL OF PHYCOLOGY 2017; 53:1325-1339. [PMID: 28949419 PMCID: PMC5725682 DOI: 10.1111/jpy.12586] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Accepted: 09/14/2017] [Indexed: 05/09/2023]
Abstract
Dinoflagellates are prolific producers of polyketide compounds, many of which are potent toxins with adverse impacts on human and marine animal health. To identify polyketide synthase (PKS) genes in the brevetoxin-producing dinoflagellate, Karenia brevis, we assembled a transcriptome from 595 million Illumina reads, sampled under different growth conditions. The assembly included 125,687 transcripts greater than 300 nt in length, with over half having >100× coverage. We found 121 transcripts encoding Type I ketosynthase (KS) domains, of which 99 encoded single KS domains, while 22 contained multiple KS domains arranged in 1-3 protein modules. Phylogenetic analysis placed all single domain and a majority of multidomain KSs within a monophyletic clade of protist PKSs. In contrast with the highly amplified single-domain KSs, only eight single-domain ketoreductase transcripts were found in the assembly, suggesting that they are more evolutionarily conserved. The multidomain PKSs were dominated by trans-acyltransferase architectures, which were recently shown to be prevalent in other algal protists. Karenia brevis also expressed several hybrid nonribosomal peptide synthetase (NRPS)/PKS sequences, including a burA-like sequence previously reported in a wide variety of dinoflagellates. This contrasts with a similarly deep transcriptome of Gambierdiscus polynesiensis, which lacked NRPS/PKS other than the burA-like transcript, and may reflect the presence of amide-containing polyketides in K. brevis and their absence from G. polynesiensis. In concert with other recent transcriptome analyses, this study provides evidence for both single domain and multidomain PKSs in the synthesis of polyketide compounds in dinoflagellates.
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Affiliation(s)
- Frances M. Van Dolah
- College of CharlestonSchool of Sciences and Mathematics66 George St.CharlestonSouth Carolina29424USA
- Hollings Marine Laboratory331 Fort Johnson Rd.CharlestonSouth Carolina29412USA
| | - Gurjeet S. Kohli
- Climate Change ClusterUniversity of Technology Sydney15 Broadway, UltimoSydneyNew South Wales2007Australia
- Singapore Centre for Environmental Life Sciences EngineeringNanyang Technological UniversitySingapore689528
| | - Jeanine S. Morey
- Hollings Marine Laboratory331 Fort Johnson Rd.CharlestonSouth Carolina29412USA
- JHT Incorporated2710 Discovery Dr.OrlandoFlorida32826USA
| | - Shauna A. Murray
- Climate Change ClusterUniversity of Technology Sydney15 Broadway, UltimoSydneyNew South Wales2007Australia
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48
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Ganley JG, Toro-Moreno M, Derbyshire ER. Exploring the Untapped Biosynthetic Potential of Apicomplexan Parasites. Biochemistry 2017; 57:365-375. [DOI: 10.1021/acs.biochem.7b00877] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Jack G. Ganley
- Department
of Chemistry, Duke University, 124 Science Drive, Durham, North Carolina 27708, United States
| | - Maria Toro-Moreno
- Department
of Chemistry, Duke University, 124 Science Drive, Durham, North Carolina 27708, United States
| | - Emily R. Derbyshire
- Department
of Chemistry, Duke University, 124 Science Drive, Durham, North Carolina 27708, United States
- Department
of Molecular Genetics and Microbiology, Duke University Medical Center, 213 Research Drive, Durham, North Carolina 27710, United States
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49
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Haq S, Bachvaroff TR, Place AR. Characterization of Acetyl-CoA Carboxylases in the Basal Dinoflagellate Amphidinium carterae. Mar Drugs 2017; 15:md15060149. [PMID: 28587129 PMCID: PMC5484099 DOI: 10.3390/md15060149] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Revised: 05/20/2017] [Accepted: 05/23/2017] [Indexed: 11/28/2022] Open
Abstract
Dinoflagellates make up a diverse array of fatty acids and polyketides. A necessary precursor for their synthesis is malonyl-CoA formed by carboxylating acetyl CoA using the enzyme acetyl-CoA carboxylase (ACC). To date, information on dinoflagellate ACC is limited. Through transcriptome analysis in Amphidinium carterae, we found three full-length homomeric type ACC sequences; no heteromeric type ACC sequences were found. We assigned the putative cellular location for these ACCs based on transit peptide predictions. Using streptavidin Western blotting along with mass spectrometry proteomics, we validated the presence of ACC proteins. Additional bands showing other biotinylated proteins were also observed. Transcript abundance for these ACCs follow the global pattern of expression for dinoflagellate mRNA messages over a diel cycle. This is one of the few descriptions at the transcriptomic and protein level of ACCs in dinoflagellates. This work provides insight into the enzymes which make the CoA precursors needed for fatty acid and toxin synthesis in dinoflagellates.
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Affiliation(s)
- Saddef Haq
- Graduate Program in Life Sciences, University of Maryland, Baltimore, MD 21201, USA.
| | - Tsvetan R Bachvaroff
- Institute of Marine and Environmental Technology, University of Maryland Center for Environmental Science, Baltimore, MD 21201, USA.
| | - Allen R Place
- Institute of Marine and Environmental Technology, University of Maryland Center for Environmental Science, Baltimore, MD 21201, USA.
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50
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Rasmussen SA, Binzer SB, Hoeck C, Meier S, de Medeiros LS, Andersen NG, Place A, Nielsen KF, Hansen PJ, Larsen TO. Karmitoxin: An Amine-Containing Polyhydroxy-Polyene Toxin from the Marine Dinoflagellate Karlodinium armiger. JOURNAL OF NATURAL PRODUCTS 2017; 80:1287-1293. [PMID: 28379705 PMCID: PMC6446557 DOI: 10.1021/acs.jnatprod.6b00860] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Marine algae from the genus Karlodinium are known to be involved in fish-killing events worldwide. Here we report for the first time the chemistry and bioactivity of a natural product from the newly described mixotrophic dinoflagellate Karlodinium armiger. Our work describes the isolation and structural characterization of a new polyhydroxy-polyene named karmitoxin. The structure elucidation work was facilitated by use of 13C enrichment and high-field 2D NMR spectroscopy, where 1H-13C long-range correlations turned out to be very informative. Karmitoxin is structurally related to amphidinols and karlotoxins; however it differs by containing the longest carbon-carbon backbone discovered for this class of compounds, as well as a primary amino group. Karmitoxin showed potent nanomolar cytotoxic activity in an RTgill-W1 cell assay as well as rapid immobilization and eventual mortality of the copepod Acartia tonsa, a natural grazer of K. armiger.
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Affiliation(s)
- Silas Anselm Rasmussen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads Building 221, DK-2800 Kgs. Lyngby, Denmark
| | - Sofie Bjørnholt Binzer
- Marine Biological Section, Department of Biology, University of Copenhagen, Strandpromenaden 5, DK-3000 Helsingør, Denmark
| | - Casper Hoeck
- Department of Chemistry, Technical University of Denmark, Kemitorvet Building 207, DK-2800 Kgs. Lyngby, Denmark
| | - Sebastian Meier
- Department of Chemistry, Technical University of Denmark, Kemitorvet Building 207, DK-2800 Kgs. Lyngby, Denmark
| | | | - Nikolaj Gedsted Andersen
- National Veterinary Institute, Technical University of Denmark, Bülowsvej 27, DK-1870 Frederiksberg C, Denmark
| | - Allen Place
- University of Maryland Center for Environmental Research, Institute of Marine and Environmental Technology, 701 E. Pratt Street, Baltimore, Maryland 21202, United States
| | - Kristian Fog Nielsen
- Marine Biological Section, Department of Biology, University of Copenhagen, Strandpromenaden 5, DK-3000 Helsingør, Denmark
| | - Per Juel Hansen
- Marine Biological Section, Department of Biology, University of Copenhagen, Strandpromenaden 5, DK-3000 Helsingør, Denmark
| | - Thomas Ostenfeld Larsen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads Building 221, DK-2800 Kgs. Lyngby, Denmark
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