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Miles CO, McCarron P, Thomas K, Al-Sinawi B, Liu T, Neilan BA. Microcystins with Modified Adda 5-Residues from a Heterologous Microcystin Expression System. ACS OMEGA 2024; 9:27618-27631. [PMID: 38947807 PMCID: PMC11209926 DOI: 10.1021/acsomega.4c03332] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/07/2024] [Revised: 05/17/2024] [Accepted: 05/28/2024] [Indexed: 07/02/2024]
Abstract
Microcystins are hepatotoxic cyclic heptapeptides produced by some cyanobacterial species and usually contain the unusual β-amino acid 3S-amino-9S-methoxy-2S,6,8S-trimethyl-10-phenyl-4E,6E-decadienoic acid (Adda) at position-5. The full microcystin gene cluster from Microcystis aeruginosa PCC 7806 has been expressed in Escherichia coli. In an earlier study, the engineered strain was shown to produce MC-LR and [d-Asp3]MC-LR, the main microcystins reported in cultures of M. aeruginosa PCC 7806. However, analysis of the engineered strain of E. coli using semitargeted liquid chromatography with high-resolution tandem mass spectrometry (LC-HRMS/MS) and thiol derivatization revealed the presence of 15 additional microcystin analogues, including four linear peptide variants and, in total, 12 variants with modifications to the Adda moiety. Four of the Adda-variants lacked the phenyl group at the Adda-terminus, a modification that has not previously been reported in cyanobacteria. Their HRMS/MS spectra contained the product-ion from Adda at m/z 135.1168, but the commonly observed product-ion at m/z 135.0804 from Adda-containing microcystins was almost completely absent. In contrast, three of the variants were missing a methyl group between C-2 and C-8 of the Adda moiety, and their LC-HRMS/MS spectra displayed the product-ion from Adda at m/z 135.0804. However, instead of the product-ion at m/z 135.1168, these three variants gave product-ions at m/z 121.1011. These observations, together with spectra from microcystin standards using in-source fragmentation, showed that the product-ion at m/z 135.1168 found in the HRMS/MS spectra of most microcystins originated from the C-2 to C-8 region of the Adda moiety. Identification of the fragmentation pathways for the Adda side chain will facilitate the detection of microcystins containing modifications in their Adda moieties that could otherwise easily be overlooked with standard LC-MS screening methods. Microcystin variants containing Abu at position-1 were also prominent components of the microcystin profile of the engineered bacterium. Microcystin variants with Abu1 or without the phenyl group on the Adda side chain were not detected in the original host cyanobacterium. This suggests not only that the microcystin synthase complex may be affected by substrate availability within its host organism but also that it possesses an unexpected degree of biosynthetic flexibility.
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Affiliation(s)
- Christopher O. Miles
- Biotoxin
Metrology, National Research Council Canada, Halifax, Nova Scotia B3H 3Z1, Canada
- Norwegian
Veterinary Institute, Postboks 64, 1431 Ås, Norway
| | - Pearse McCarron
- Biotoxin
Metrology, National Research Council Canada, Halifax, Nova Scotia B3H 3Z1, Canada
| | - Krista Thomas
- Biotoxin
Metrology, National Research Council Canada, Halifax, Nova Scotia B3H 3Z1, Canada
| | - Bakir Al-Sinawi
- Diagnostic
Technology Pty. Ltd., Sydney 2085, NSW, Australia
- School
of Environmental and Life Sciences, The
University of Newcastle, Callaghan 2308, NSW, Australia
| | - Tianzhe Liu
- Diagnostic
Technology Pty. Ltd., Sydney 2085, NSW, Australia
- Department
of Chemistry and Food Chemistry, Technical
University of Dresden, 01069 Dresden, Germany
| | - Brett A. Neilan
- School
of Environmental and Life Sciences, The
University of Newcastle, Callaghan 2308, NSW, Australia
- ARC Centre
of Excellence in Synthetic Biology, Sydney, NSW 2019, Australia
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2
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Glasser NR, Cui D, Risser DD, Okafor CD, Balskus EP. Accelerating the discovery of alkyl halide-derived natural products using halide depletion. Nat Chem 2024; 16:173-182. [PMID: 38216751 PMCID: PMC10849952 DOI: 10.1038/s41557-023-01390-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Accepted: 10/30/2023] [Indexed: 01/14/2024]
Abstract
Even in the genomic era, microbial natural product discovery workflows can be laborious and limited in their ability to target molecules with specific structural features. Here we leverage an understanding of biosynthesis to develop a workflow that targets the discovery of alkyl halide-derived natural products by depleting halide anions, a key biosynthetic substrate for enzymatic halogenation, from microbial growth media. By comparing the metabolomes of bacterial cultures grown in halide-replete and deficient media, we rapidly discovered the nostochlorosides, the products of an orphan halogenase-encoding gene cluster from Nostoc punctiforme ATCC 29133. We further found that these products, a family of unusual chlorinated glycolipids featuring the rare sugar gulose, are polymerized via an unprecedented enzymatic etherification reaction. Together, our results highlight the power of leveraging an understanding of biosynthetic logic to streamline natural product discovery.
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Affiliation(s)
- Nathaniel R Glasser
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA
| | - Dongtao Cui
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA
| | - Douglas D Risser
- Department of Biology, University of the Pacific, Stockton, CA, USA
| | - C Denise Okafor
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, PA, USA
- Department of Chemistry, Pennsylvania State University, University Park, PA, USA
| | - Emily P Balskus
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA.
- Howard Hughes Medical Institute, Harvard University, Cambridge, MA, USA.
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Li Z, Zhu X, Wu Z, Sun T, Tong Y. Recent Advances in Cyanotoxin Synthesis and Applications: A Comprehensive Review. Microorganisms 2023; 11:2636. [PMID: 38004647 PMCID: PMC10673588 DOI: 10.3390/microorganisms11112636] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Revised: 10/23/2023] [Accepted: 10/24/2023] [Indexed: 11/26/2023] Open
Abstract
Over the past few decades, nearly 300 known cyanotoxins and more than 2000 cyanobacterial secondary metabolites have been reported from the environment. Traditional studies have focused on the toxic cyanotoxins produced by harmful cyanobacteria, which pose a risk to both human beings and wildlife, causing acute and chronic poisoning, resulting in diarrhea, nerve paralysis, and proliferation of cancer cells. Actually, the biotechnological potential of cyanotoxins is underestimated, as increasing studies have demonstrated their roles as valuable products, including allelopathic agents, insecticides and biomedicines. To promote a comprehensive understanding of cyanotoxins, a critical review is in demand. This review aims to discuss the classifications; biosynthetic pathways, especially heterogenous production; and potential applications of cyanotoxins. In detail, we first discuss the representative cyanotoxins and their toxic effects, followed by an exploration of three representative biosynthetic pathways (non-ribosomal peptide synthetases, polyketide synthetases, and their combinations). In particular, advances toward the heterologous biosynthesis of cyanotoxins in vitro and in vivo are summarized and compared. Finally, we indicate the potential applications and solutions to bottlenecks for cyanotoxins. We believe that this review will promote a comprehensive understanding, synthetic biology studies, and potential applications of cyanotoxins in the future.
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Affiliation(s)
- Zipeng Li
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China; (Z.L.); (Z.W.)
| | - Xiaofei Zhu
- Laboratory of Synthetic Microbiology, School of Chemical Engineering & Technology, Tianjin University, Tianjin 300072, China;
| | - Zhengyu Wu
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China; (Z.L.); (Z.W.)
| | - Tao Sun
- Laboratory of Synthetic Microbiology, School of Chemical Engineering & Technology, Tianjin University, Tianjin 300072, China;
- Center for Biosafety Research and Strategy, Tianjin University, Tianjin 300072, China
| | - Yindong Tong
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China; (Z.L.); (Z.W.)
- College of Ecology and Environment, Tibet University, Lhasa 850000, China
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Zheng Y, Xue C, Chen H, Jia A, Zhao L, Zhang J, Zhang L, Wang Q. Reconstitution and expression of mcy gene cluster in the model cyanobacterium Synechococcus 7942 reveals a role of MC-LR in cell division. THE NEW PHYTOLOGIST 2023; 238:1101-1114. [PMID: 36683448 DOI: 10.1111/nph.18766] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Accepted: 01/12/2023] [Indexed: 06/17/2023]
Abstract
Cyanobacterial blooms pose a serious threat to public health due to the presence of cyanotoxins. Microcystin-LR (MC-LR) produced by Microcystis aeruginosa is the most common cyanotoxins. Due to the limitation of isolation, purification, and genetic manipulation techniques, it is difficult to study and verify in situ the biosynthetic pathways and molecular mechanisms of MC-LR. We reassembled the biosynthetic gene cluster (mcy cluster) of MC-LR in vitro by synthetic biology, designed and constructed the strong bidirectional promoter biPpsbA2 , transformed it into Synechococcus 7942, and successfully expressed MC-LR at a level of 0.006-0.018 fg cell-1 d-1 . We found the expression of MC-LR led to abnormal cell division and cellular filamentation, further using various methods proved that by irreversibly competing its GTP-binding site, MC-LR inhibits assembly of the cell division protein FtsZ. The study represents the first reconstitution and expression of the mcy cluster and the autotrophic production of MC-LR in model cyanobacterium, which lays the foundation for resolving the microcystins biosynthesis pathway. The discovered role of MC-LR in cell division reveals a mechanism of how blooming cyanobacteria gain a competitive edge over their nonblooming counterparts.
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Affiliation(s)
- Yanli Zheng
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng, 475004, China
| | - Chunling Xue
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng, 475004, China
| | - Hui Chen
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng, 475004, China
| | - Anqi Jia
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng, 475004, China
| | - Liang Zhao
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng, 475004, China
| | - Junli Zhang
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng, 475004, China
| | - Lixin Zhang
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng, 475004, China
- Academy for Advanced Interdisciplinary Studies, Henan University, Kaifeng, 475004, China
| | - Qiang Wang
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng, 475004, China
- Academy for Advanced Interdisciplinary Studies, Henan University, Kaifeng, 475004, China
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5
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Dhakal D, Kokkaliari S, Rubin GM, Paul VJ, Ding Y, Luesch H. Biosynthesis of Lyngbyastatins 1 and 3, Cytotoxic Depsipeptides from an Okeania sp. Marine Cyanobacterium. JOURNAL OF NATURAL PRODUCTS 2023; 86:85-93. [PMID: 36546857 PMCID: PMC10197921 DOI: 10.1021/acs.jnatprod.2c00782] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Lyngbyastatins (Lbns) 1 (1) and 3 (2) belong to a group of cyclic depsipeptides that inhibit cancer cell proliferation. These compounds have been isolated from different marine cyanobacterial collections, while further development of these compounds relies on their lengthy total synthesis. Biosynthetic studies of these compounds can provide viable strategies to access these compounds and develop new analogs. In this study, we report the identification and characterization of one Lbn biosynthetic gene cluster (BGC) from the marine cyanobacterium Okeania sp. VPG18-21. We initially identified 1 and 2 in the organic extract by mass spectrometry and performed the targeted isolation of these compounds, which feature a (2S,3R)-3-amino-2-methylpentanoic acid (MAP) and a (2S,3R)-3-amino-2-methylhexanoic acid (Amha) moiety, respectively. Parallel metagenomic sequencing of VPG18-21 led to the identification of a putative Lbn BGC that encodes six megaenzymes (LbnA-F), including one polyketide synthase (PKS, LbnE), four nonribosomal peptide synthetases (NRPSs, LbnB-D and -F), and one PKS-NRPS hybrid (LbnA). Bioinformatic analysis of these enzymes suggested that the BGC produces 1 and 2. Furthermore, our biochemical studies of three recombinant adenylation domains uncovered their substrate specificities, supporting the identity of the BGC. Finally, we identified near-complete Lbn-like BGCs in the genomes of two other marine cyanobacteria.
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Affiliation(s)
- Dipesh Dhakal
- Department of Medicinal Chemistry and Center for Natural Products, Drug Discovery and Development (CNPD3), University of Florida, 1345 Center Drive, Gainesville, Florida 32610, United States
| | - Sofia Kokkaliari
- Department of Medicinal Chemistry and Center for Natural Products, Drug Discovery and Development (CNPD3), University of Florida, 1345 Center Drive, Gainesville, Florida 32610, United States
| | - Garret M. Rubin
- Department of Medicinal Chemistry and Center for Natural Products, Drug Discovery and Development (CNPD3), University of Florida, 1345 Center Drive, Gainesville, Florida 32610, United States
| | - Valerie J. Paul
- Smithsonian Marine Station at Ft. Pierce, 701 Seaway Drive, Ft. Pierce, Florida 34949, United States
| | - Yousong Ding
- Department of Medicinal Chemistry and Center for Natural Products, Drug Discovery and Development (CNPD3), University of Florida, 1345 Center Drive, Gainesville, Florida 32610, United States
| | - Hendrik Luesch
- Department of Medicinal Chemistry and Center for Natural Products, Drug Discovery and Development (CNPD3), University of Florida, 1345 Center Drive, Gainesville, Florida 32610, United States
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6
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Liu J, Chen L, Zhang X. Current research scenario for biological effect of exogenous factors on microcystin synthesis. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:26190-26201. [PMID: 35089514 DOI: 10.1007/s11356-021-18256-x] [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: 09/08/2021] [Accepted: 12/17/2021] [Indexed: 06/14/2023]
Abstract
In natural water bodies, numerous cyanobacteria have the potential to intracellularly synthesize cyanotoxins, among which microcystin (MC) is the ubiquitous toxin that has been well known to be carcinogenic for hepatocytes. MC synthesis is a complex process, which involves about 10 non-ribosomal proteins encoded by the mcy gene cluster. In the natural environments containing MC-producing cyanobacteria, a variety of external factors can affect the generation of MC by mediating the expression of synthesizing genes. These factors can be generally divided into biotic factors (e.g., daphnia, virioplankton, MC-degrading bacteria, algicidal bacteria) and abiotic factors (e.g., nutrients, physical factors, chemicals, phytochemicals, essential trace elements), which are of great significance to the effective reduction of MC. Furthermore, comparison of MC-synthesizing genes in different cyanobacterial strains was performed, and the related factors affecting MC synthesis were summarized. Then, the problems and gaps regarding the biological effect of exogenous factors on microcystin synthesis were discussed. This review article may provide new ideas for addressing the challenges and bottlenecks of MC management.
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Affiliation(s)
- Jiahui Liu
- Department of Occupational and Environmental Health, Xiangya School of Public Health, Central South University, Changsha, China
| | - Lv Chen
- Department of Occupational and Environmental Health, Xiangya School of Public Health, Central South University, Changsha, China
| | - Xian Zhang
- Department of Occupational and Environmental Health, Xiangya School of Public Health, Central South University, Changsha, China.
- Hunan Provincial Key Laboratory of Clinical Epidemiology, Central South University, Changsha, China.
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7
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Li J, Feng M, Yu X. Rapid detection of mcyG gene of microcystins producing cyanobacteria in water samples by recombinase polymerase amplification combined with lateral flow strips. JOURNAL OF WATER AND HEALTH 2021; 19:907-917. [PMID: 34874899 DOI: 10.2166/wh.2021.091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Nowadays, cyanobacteria blooms and microcystins (MCs) pollution are threatening water safety and public health. In this study, a rapid detection method was established for detecting MCs producing cyanobacteria. The MC synthesis gene mcyG was measured through recombinase polymerase amplification combined with lateral flow strips (LF-RPA) technology. The target gene mcyG was amplified at a temperature range of 37-45 °C, and the amplification time to detect mcyG was only 15 min at 37 °C. The optimal reaction conditions were confirmed using single dependent variable experiments, suggesting that the best probe dosage for 50 μL of the reaction mixture was 0.2 μL, the best dilution ratio of products was 1/100, and the best loading volume was 10 μL. The specificity test proved that the LF-RPA assay could distinguish MCs producing cyanobacteria from nontoxic algae well. Within 35 min of amplification time, the detection limit of the LF-RPA assay was 103 copies/mL mcyG and 104 cells/mL Microcystis aeruginosa FACHB-905. Overall, the LF-RPA assay could detect MCs producing cyanobacteria in water samples quickly and accurately, and it has a great promise to be applied for monitoring the MCs producing cyanobacteria blooms in natural waters.
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Affiliation(s)
- Jingjing Li
- Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Mingbao Feng
- College of the Environment & Ecology, Xiamen University, Xiamen 361005, China E-mail:
| | - Xin Yu
- College of the Environment & Ecology, Xiamen University, Xiamen 361005, China E-mail:
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8
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9
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Cullen A, Pearson LA, Mazmouz R, Liu T, Soeriyadi AH, Ongley SE, Neilan BA. Heterologous expression and biochemical characterisation of cyanotoxin biosynthesis pathways. Nat Prod Rep 2019; 36:1117-1136. [DOI: 10.1039/c8np00063h] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This review discusses cyanotoxin biosynthetic pathways and highlights the heterologous expression and biochemical studies used to characterise them.
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Affiliation(s)
- Alescia Cullen
- School of Environmental and Life Sciences
- University of Newcastle
- Callaghan 2308
- Australia
| | - Leanne A. Pearson
- School of Environmental and Life Sciences
- University of Newcastle
- Callaghan 2308
- Australia
| | - Rabia Mazmouz
- School of Environmental and Life Sciences
- University of Newcastle
- Callaghan 2308
- Australia
| | - Tianzhe Liu
- School of Biotechnology and Biomolecular Sciences
- The University of New South Wales
- Sydney 2052
- Australia
| | - Angela H. Soeriyadi
- School of Biotechnology and Biomolecular Sciences
- The University of New South Wales
- Sydney 2052
- Australia
| | - Sarah E. Ongley
- School of Environmental and Life Sciences
- University of Newcastle
- Callaghan 2308
- Australia
| | - Brett A. Neilan
- School of Environmental and Life Sciences
- University of Newcastle
- Callaghan 2308
- Australia
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10
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Biosynthesis of microcystin hepatotoxins in the cyanobacterial genus Fischerella. Toxicon 2017; 141:43-50. [PMID: 29154789 DOI: 10.1016/j.toxicon.2017.10.021] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Revised: 10/18/2017] [Accepted: 10/22/2017] [Indexed: 01/13/2023]
Abstract
Microcystins (MCs) are serine/threonine phosphatase inhibitors synthesized by several members of the phylum Cyanobacteria. Mining the draft genome sequence of the nostocalean MC-producing Fischerella sp. strain CENA161 led to the identification of three contigs containing mcy genes. Subsequent PCR and Sanger sequencing allowed the assembling of its complete biosynthetic mcy gene cluster with 55,016 bases in length. The cluster encoding ten genes (mcyA-J) with a central bidirectional promoter was organized in a similar manner as found in other genera of nostocalean cyanobacteria. However, the nucleotide sequence of the mcy gene cluster of Fischerella sp. CENA161 showed significant differences from all the other MC-producing cyanobacterial genera, sharing only 85.2 to 74.1% identities. Potential MC variants produced by Fischerella sp. CENA161 were predicted by the analysis of the adenylation domain binding pockets and further investigated by LC-MS/MS analysis. To our knowledge, this study presents the first complete mcy cluster characterization from a strain of the genus Fischerella, providing new insight into the distribution and evolution of MCs in the phylum Cyanobacteria.
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11
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Takeda K, Kemmoku K, Satoh Y, Ogasawara Y, Shin-ya K, Dairi T. N-Phenylacetylation and Nonribosomal Peptide Synthetases with Substrate Promiscuity for Biosynthesis of Heptapeptide Variants, JBIR-78 and JBIR-95. ACS Chem Biol 2017; 12:1813-1819. [PMID: 28505407 DOI: 10.1021/acschembio.7b00314] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
JBIR-78 (1) and JBIR-95 (2), both of which are heptapeptide derivatives isolated from Kibdelosporangium sp. AK-AA56, have the same amino acid sequences except for the second amino acid: phenylacetic acid (Paa)-l-Val-d-Asp (1)/d-cysteic acid (2)-l-Ala-(3S)-3-hydroxy-d-Leu-Gly-d-Ala-l-Phe. Heterologous expression of the biosynthetic gene cluster including genes encoding nonribosomal peptide synthetases (NRPS) and in vitro assays with recombinant Orf3, an l-cysteic acid synthase homologue, suggested the single A domain in module 2 activates both l-Asp and l-cysteic acid to yield 1 and 2, respectively, although the substrate specificities of the A domains of NRPSs are usually strict. Biosynthetic mechanism of introduction of N-terminal Paa was also investigated. Recombinant Orf1 and Orf2 similar to subunits of pyruvate dehydrogenase complex catalyzed the conversion of phenylpyruvate into phenylacetyl-CoA together with dihydrolipoyl dehydrogenase whose encoding gene is located outside of the gene cluster. Moreover, we showed that phenylacetyl-CoA was directly condensed with l-Val, which was tethered to a peptidyl carrier protein, at the first condensation domain in the NRPS.
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Affiliation(s)
- Kunpei Takeda
- Graduate
School of Engineering, Hokkaido University, N13-W8, Kita-ku,
Sapporo, Hokkaido 060-8628, Japan
| | - Kohei Kemmoku
- Graduate
School of Engineering, Hokkaido University, N13-W8, Kita-ku,
Sapporo, Hokkaido 060-8628, Japan
| | - Yasuharu Satoh
- Graduate
School of Engineering, Hokkaido University, N13-W8, Kita-ku,
Sapporo, Hokkaido 060-8628, Japan
| | - Yasushi Ogasawara
- Graduate
School of Engineering, Hokkaido University, N13-W8, Kita-ku,
Sapporo, Hokkaido 060-8628, Japan
| | - Kazuo Shin-ya
- Biomedicinal
Information Research Center (BIRC), National Institute of Advanced Industrial Science and Technology (AIST), 2-4-7 Aomi, Koto-ku, Tokyo 135-0064, Japan
| | - Tohru Dairi
- Graduate
School of Engineering, Hokkaido University, N13-W8, Kita-ku,
Sapporo, Hokkaido 060-8628, Japan
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Abstract
The enzymology of 135 assembly lines containing primarily cis-acyltransferase modules is comprehensively analyzed, with greater attention paid to less common phenomena. Diverse online transformations, in which the substrate and/or product of the reaction is an acyl chain bound to an acyl carrier protein, are classified so that unusual reactions can be compared and underlying assembly-line logic can emerge. As a complement to the chemistry surrounding the loading, extension, and offloading of assembly lines that construct primarily polyketide products, structural aspects of the assembly-line machinery itself are considered. This review of assembly-line phenomena, covering the literature up to 2017, should thus be informative to the modular polyketide synthase novice and expert alike.
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Affiliation(s)
- Adrian T Keatinge-Clay
- Department of Molecular Biosciences, The University of Texas at Austin , Austin, Texas 78712, United States
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13
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Fu C, Auerbach D, Li Y, Scheid U, Luxenburger E, Garcia R, Irschik H, Müller R. Die Lösung des Rätsels um den Verlust eines Kohlenstoffatoms in der Ripostatin-Biosynthese. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201609950] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Chengzhang Fu
- Helmholtz-Institut für Pharmazeutische Forschung Saarland (HIPS); Helmholtz-Zentrum für Infektionsforschung (HZI); Universität des Saarlandes; Campus Gebäude E8.1 66123 Saarbrücken Deutschland
| | - David Auerbach
- Helmholtz-Institut für Pharmazeutische Forschung Saarland (HIPS); Helmholtz-Zentrum für Infektionsforschung (HZI); Universität des Saarlandes; Campus Gebäude E8.1 66123 Saarbrücken Deutschland
| | - Yanyan Li
- Helmholtz-Institut für Pharmazeutische Forschung Saarland (HIPS); Helmholtz-Zentrum für Infektionsforschung (HZI); Universität des Saarlandes; Campus Gebäude E8.1 66123 Saarbrücken Deutschland
- Laboratory Molecules of Communication and Adaptation o Microorganisms (MCAM, UMR 7245 CNRS-MNHN); Sorbonne Universités; Muséum National d'Histoire Naturelle; Centre National de la Recherche Scientifique, CP 54; 57 rue Cuvier 75005 Paris Frankreich
| | - Ullrich Scheid
- Helmholtz-Institut für Pharmazeutische Forschung Saarland (HIPS); Helmholtz-Zentrum für Infektionsforschung (HZI); Universität des Saarlandes; Campus Gebäude E8.1 66123 Saarbrücken Deutschland
- Deutsches Zentrum für Infektionsforschung; Inhoffenstraße 7 38124 Braunschweig Deutschland
| | - Eva Luxenburger
- Helmholtz-Institut für Pharmazeutische Forschung Saarland (HIPS); Helmholtz-Zentrum für Infektionsforschung (HZI); Universität des Saarlandes; Campus Gebäude E8.1 66123 Saarbrücken Deutschland
- Deutsches Zentrum für Infektionsforschung; Inhoffenstraße 7 38124 Braunschweig Deutschland
| | - Ronald Garcia
- Helmholtz-Institut für Pharmazeutische Forschung Saarland (HIPS); Helmholtz-Zentrum für Infektionsforschung (HZI); Universität des Saarlandes; Campus Gebäude E8.1 66123 Saarbrücken Deutschland
- Deutsches Zentrum für Infektionsforschung; Inhoffenstraße 7 38124 Braunschweig Deutschland
| | - Herbert Irschik
- Helmholtz-Zentrum für Infektionsforschung (HZI); Inhoffenstraße 7 38124 Braunschweig Deutschland
| | - Rolf Müller
- Helmholtz-Institut für Pharmazeutische Forschung Saarland (HIPS); Helmholtz-Zentrum für Infektionsforschung (HZI); Universität des Saarlandes; Campus Gebäude E8.1 66123 Saarbrücken Deutschland
- Deutsches Zentrum für Infektionsforschung; Inhoffenstraße 7 38124 Braunschweig Deutschland
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Fu C, Auerbach D, Li Y, Scheid U, Luxenburger E, Garcia R, Irschik H, Müller R. Solving the Puzzle of One-Carbon Loss in Ripostatin Biosynthesis. Angew Chem Int Ed Engl 2017; 56:2192-2197. [DOI: 10.1002/anie.201609950] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Indexed: 01/19/2023]
Affiliation(s)
- Chengzhang Fu
- Helmholtz Institute for Pharmaceutical Research Saarland (HIPS); Helmholtz Centre for Infection Research (HZI); Saarland University; Campus Building E8.1 66123 Saarbrücken Germany
| | - David Auerbach
- Helmholtz Institute for Pharmaceutical Research Saarland (HIPS); Helmholtz Centre for Infection Research (HZI); Saarland University; Campus Building E8.1 66123 Saarbrücken Germany
| | - Yanyan Li
- Helmholtz Institute for Pharmaceutical Research Saarland (HIPS); Helmholtz Centre for Infection Research (HZI); Saarland University; Campus Building E8.1 66123 Saarbrücken Germany
- Current address: Laboratory Molecules of Communication and Adaptation of Microorganisms (MCAM, UMR 7245 CNRS-MNHN); Sorbonne Universités; Muséum National d'Histoire Naturelle; Centre National de la Recherche Scientifique, CP 54; 57 rue Cuvier 75005 Paris France
| | - Ullrich Scheid
- Helmholtz Institute for Pharmaceutical Research Saarland (HIPS); Helmholtz Centre for Infection Research (HZI); Saarland University; Campus Building E8.1 66123 Saarbrücken Germany
- German Centre for Infection Research (DZIF); partner site Hannover-Braunschweig; Braunschweig Germany
| | - Eva Luxenburger
- Helmholtz Institute for Pharmaceutical Research Saarland (HIPS); Helmholtz Centre for Infection Research (HZI); Saarland University; Campus Building E8.1 66123 Saarbrücken Germany
- German Centre for Infection Research (DZIF); partner site Hannover-Braunschweig; Braunschweig Germany
| | - Ronald Garcia
- Helmholtz Institute for Pharmaceutical Research Saarland (HIPS); Helmholtz Centre for Infection Research (HZI); Saarland University; Campus Building E8.1 66123 Saarbrücken Germany
- German Centre for Infection Research (DZIF); partner site Hannover-Braunschweig; Braunschweig Germany
| | - Herbert Irschik
- Helmholtz Centre for Infection Research (HZI); Inhoffenstrasse 7 38124 Braunschweig Germany
| | - Rolf Müller
- Helmholtz Institute for Pharmaceutical Research Saarland (HIPS); Helmholtz Centre for Infection Research (HZI); Saarland University; Campus Building E8.1 66123 Saarbrücken Germany
- German Centre for Infection Research (DZIF); partner site Hannover-Braunschweig; Braunschweig Germany
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15
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Rastogi RP, Madamwar D, Incharoensakdi A. Bloom Dynamics of Cyanobacteria and Their Toxins: Environmental Health Impacts and Mitigation Strategies. Front Microbiol 2015; 6:1254. [PMID: 26635737 PMCID: PMC4646972 DOI: 10.3389/fmicb.2015.01254] [Citation(s) in RCA: 115] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2015] [Accepted: 10/28/2015] [Indexed: 11/13/2022] Open
Abstract
Cyanobacteria are ecologically one of the most prolific groups of phototrophic prokaryotes in both marine and freshwater habitats. Both the beneficial and detrimental aspects of cyanobacteria are of considerable significance. They are important primary producers as well as an immense source of several secondary products, including an array of toxic compounds known as cyanotoxins. Abundant growth of cyanobacteria in freshwater, estuarine, and coastal ecosystems due to increased anthropogenic eutrophication and global climate change has created serious concern toward harmful bloom formation and surface water contamination all over the world. Cyanobacterial blooms and the accumulation of several cyanotoxins in water bodies pose severe ecological consequences with high risk to aquatic organisms and global public health. The proper management for mitigating the worldwide incidence of toxic cyanobacterial blooms is crucial for maintenance and sustainable development of functional ecosystems. Here, we emphasize the emerging information on the cyanobacterial bloom dynamics, toxicology of major groups of cyanotoxins, as well as a perspective and integrative approach to their management.
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Affiliation(s)
- Rajesh P. Rastogi
- BRD School of Biosciences, Sardar Patel UniversityAnand, India
- Laboratory of Cyanobacterial Biotechnology, Department of Biochemistry, Faculty of Science, Chulalongkorn UniversityBangkok, Thailand
| | - Datta Madamwar
- BRD School of Biosciences, Sardar Patel UniversityAnand, India
| | - Aran Incharoensakdi
- Laboratory of Cyanobacterial Biotechnology, Department of Biochemistry, Faculty of Science, Chulalongkorn UniversityBangkok, Thailand
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16
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Tan XF, Dai YN, Zhou K, Jiang YL, Ren YM, Chen Y, Zhou CZ. Structure of the adenylation–peptidyl carrier protein didomain of theMicrocystis aeruginosamicrocystin synthetase McyG. ACTA ACUST UNITED AC 2015; 71:873-81. [DOI: 10.1107/s1399004715001716] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2014] [Accepted: 01/27/2015] [Indexed: 11/11/2022]
Abstract
Microcystins, which are the most common cause of hepatotoxicity associated with cyanobacterial water blooms, are assembledin vivoon a large multienzyme complexviaa mixed nonribosomal peptide synthetase/polyketide synthetase (NRPS/PKS). The biosynthesis of microcystin inMicrocystis aeruginosaPCC 7806 starts with the enzyme McyG, which contains an adenylation–peptidyl carrier protein (A–PCP) didomain for loading the starter unit to assemble the side chain of an Adda residue. However, the catalytic mechanism remains unclear. Here, the 2.45 Å resolution crystal structure of the McyG A–PCP didomain complexed with the catalytic intermediate L-phenylalanyl-adenylate (L-Phe-AMP) is reported. Each asymmetric unit contains two protein molecules, one of which consists of the A–PCP didomain and the other of which comprises only the A domain. Structural analyses suggest that Val227 is likely to be critical for the selection of hydrophobic substrates. Moreover, two distinct interfaces demonstrating variable crosstalk between the PCP domain and the A domain were observed. A catalytic cycle for the adenylation and peptide transfer of the A–PCP didomain is proposed.
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17
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Micallef ML, D'Agostino PM, Al-Sinawi B, Neilan BA, Moffitt MC. Exploring cyanobacterial genomes for natural product biosynthesis pathways. Mar Genomics 2014; 21:1-12. [PMID: 25482899 DOI: 10.1016/j.margen.2014.11.009] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Revised: 11/22/2014] [Accepted: 11/23/2014] [Indexed: 11/26/2022]
Abstract
Cyanobacteria produce a vast array of natural products, some of which are toxic to human health, while others possess potential pharmaceutical activities. Genome mining enables the identification and characterisation of natural product gene clusters; however, the current number of cyanobacterial genomes remains low compared to other phyla. There has been a recent effort to rectify this issue by increasing the number of sequenced cyanobacterial genomes. This has enabled the identification of biosynthetic gene clusters for structurally diverse metabolites, including non-ribosomal peptides, polyketides, ribosomal peptides, UV-absorbing compounds, alkaloids, terpenes and fatty acids. While some of the identified biosynthetic gene clusters correlate with known metabolites, genome mining also highlights the number and diversity of clusters for which the product is unknown (referred to as orphan gene clusters). A number of bioinformatic tools have recently been developed in order to predict the products of orphan gene clusters; however, in some cases the complexity of the cyanobacterial pathways makes the prediction problematic. This can be overcome by the use of mass spectrometry-guided natural product genome mining, or heterologous expression. Application of these techniques to cyanobacterial natural product gene clusters will be explored.
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Affiliation(s)
- Melinda L Micallef
- School of Science and Health, University of Western Sydney, Campbelltown, NSW 2560, Australia
| | - Paul M D'Agostino
- School of Science and Health, University of Western Sydney, Campbelltown, NSW 2560, Australia; School of Biotechnology and Biomolecular Sciences, University of New South Wales, Kensington, NSW 2052, Australia
| | - Bakir Al-Sinawi
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Kensington, NSW 2052, Australia
| | - Brett A Neilan
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Kensington, NSW 2052, Australia
| | - Michelle C Moffitt
- School of Science and Health, University of Western Sydney, Campbelltown, NSW 2560, Australia.
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18
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Niedermeyer THJ, Daily A, Swiatecka-Hagenbruch M, Moscow JA. Selectivity and potency of microcystin congeners against OATP1B1 and OATP1B3 expressing cancer cells. PLoS One 2014; 9:e91476. [PMID: 24614281 PMCID: PMC3948918 DOI: 10.1371/journal.pone.0091476] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Accepted: 02/13/2014] [Indexed: 11/19/2022] Open
Abstract
Microcystins are potent phosphatase inhibitors and cellular toxins. They require active transport by OATP1B1 and OATP1B3 transporters for uptake into human cells, and the high expression of these transporters in the liver accounts for their selective hepatic toxicity. Several human tumors have been shown to have high levels of expression of OATP1B3 but not OATP1B1, the main transporter in liver cells. We hypothesized that microcystin variants could be isolated that are transported preferentially by OATP1B3 relative to OATP1B1 to advance as anticancer agents with clinically tolerable hepatic toxicity. Microcystin variants have been isolated and tested for cytotoxicity in cancer cells stably transfected with OATP1B1 and OATP1B3 transporters. Microcystin variants with cytotoxic OATP1B1/OATP1B3 IC50 ratios that ranged between 0.2 and 32 were found, representing a 150-fold range in transporter selectivity. As microcystin structure has a significant impact on transporter selectivity, it is potentially possible to develop analogs with even more pronounced OATP1B3 selectivity and thus enable their development as anticancer drugs.
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Affiliation(s)
- Timo H. J. Niedermeyer
- Cyano Biotech GmbH, Berlin, Germany
- Interfaculty Institute for Microbiology and Infection Medicine, University of Tübingen, Tübingen, Germany
- * E-mail:
| | - Abigail Daily
- Department of Pediatrics, University of Kentucky, Lexington, Kentucky, United States of America
| | | | - Jeffrey A. Moscow
- Department of Pediatrics, University of Kentucky, Lexington, Kentucky, United States of America
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19
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Bouhired SM, Crüsemann M, Almeida C, Weber T, Piel J, Schäberle TF, König GM. Biosynthesis of Phenylnannolone A, a Multidrug Resistance Reversal Agent from the Halotolerant MyxobacteriumNannocystis pusillaB150. Chembiochem 2014; 15:757-65. [DOI: 10.1002/cbic.201300676] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2013] [Indexed: 01/28/2023]
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20
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Dittmann E, Fewer DP, Neilan BA. Cyanobacterial toxins: biosynthetic routes and evolutionary roots. FEMS Microbiol Rev 2013; 37:23-43. [DOI: 10.1111/j.1574-6976.2012.12000.x] [Citation(s) in RCA: 239] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2011] [Revised: 08/22/2012] [Accepted: 08/24/2012] [Indexed: 11/27/2022] Open
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21
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Liu L, Bearden DW, Rodriguez JC, Rein KS. Biosynthesis of Athmu, a α,γ-hydroxy-β-amino acid of pahayokolides A-B. Tetrahedron Lett 2012; 53:6758-6760. [PMID: 23172981 PMCID: PMC3500633 DOI: 10.1016/j.tetlet.2012.09.119] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Pahayokolides A-B are cyanobacteria derived non-ribosomal peptides which exhibit cytotoxicity against a number of cancer cell lines. The biosynthetic origin of the 3-amino-2,5,7,8-tetrahydroxy-10-methylundecanoic acid (Athmu) moiety has been investigated using stable isotope incorporation experiments. While α-ketoisocaproic acid (α-KIC), α-hydroxyisocaproic acid (α-HIC) and leucine all serve as precursors to Athmu, the feeding of [1-(13)C] α-KIC results in more than threefold greater (13)C enrichment than the other precursors. This result suggests that α-KIC is the immediate precursor which is selected and activated by the adenylation domain of the loading NRPS module and subsequently reduced in a fashion similar to that of the recently identified pathways for cryptophycins A-B, cereulide and valinomycin.
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Affiliation(s)
- Li Liu
- Department of Chemistry and Biochemistry, Florida International University, Miami, Florida 33199, United States
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22
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Kehr JC, Gatte Picchi D, Dittmann E. Natural product biosyntheses in cyanobacteria: A treasure trove of unique enzymes. Beilstein J Org Chem 2011; 7:1622-35. [PMID: 22238540 PMCID: PMC3252866 DOI: 10.3762/bjoc.7.191] [Citation(s) in RCA: 102] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2011] [Accepted: 09/19/2011] [Indexed: 11/25/2022] Open
Abstract
Cyanobacteria are prolific producers of natural products. Investigations into the biochemistry responsible for the formation of these compounds have revealed fascinating mechanisms that are not, or only rarely, found in other microorganisms. In this article, we survey the biosynthetic pathways of cyanobacteria isolated from freshwater, marine and terrestrial habitats. We especially emphasize modular nonribosomal peptide synthetase (NRPS) and polyketide synthase (PKS) pathways and highlight the unique enzyme mechanisms that were elucidated or can be anticipated for the individual products. We further include ribosomal natural products and UV-absorbing pigments from cyanobacteria. Mechanistic insights obtained from the biochemical studies of cyanobacterial pathways can inspire the development of concepts for the design of bioactive compounds by synthetic-biology approaches in the future.
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Affiliation(s)
- Jan-Christoph Kehr
- University of Potsdam, Institute for Biochemistry and Biology, Karl-Liebknecht-Str. 24/25, 14476 Potsdam-Golm, Germany
| | - Douglas Gatte Picchi
- University of Potsdam, Institute for Biochemistry and Biology, Karl-Liebknecht-Str. 24/25, 14476 Potsdam-Golm, Germany
| | - Elke Dittmann
- University of Potsdam, Institute for Biochemistry and Biology, Karl-Liebknecht-Str. 24/25, 14476 Potsdam-Golm, Germany
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23
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Nostophycin biosynthesis is directed by a hybrid polyketide synthase-nonribosomal peptide synthetase in the toxic cyanobacterium Nostoc sp. strain 152. Appl Environ Microbiol 2011; 77:8034-40. [PMID: 21948844 DOI: 10.1128/aem.05993-11] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Cyanobacteria are a rich source of natural products with interesting pharmaceutical properties. Here, we report the identification, sequencing, annotation, and biochemical analysis of the nostophycin (npn) biosynthetic gene cluster. The npn gene cluster spans 45.1 kb and consists of three open reading frames encoding a polyketide synthase, a mixed polyketide nonribosomal peptide synthetase, and a nonribosomal peptide synthetase. The genetic architecture and catalytic domain organization of the proteins are colinear in arrangement, with the putative order of the biosynthetic assembly of the cyclic heptapeptide. NpnB contains an embedded monooxygenase domain linking nonribosomal peptide synthetase (NRPS) and polyketide synthase (PKS) catalytic domains and predicted here to hydroxylate the nostophycin during assembly. Expression of the adenylation domains and subsequent substrate specificity assays support the involvement of this cluster in nostophycin biosynthesis. Biochemical analyses suggest that the loading substrate of NpnA is likely to be a phenylpropanoic acid necessitating deletion of a carbon atom to explain the biosynthesis of nostophycin. Biosyntheses of nostophycin and microcystin resemble each other, but the phylogenetic analyses suggest that they are distantly related to one another.
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24
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Gulder TAM, Freeman MF, Piel J. The Catalytic Diversity of Multimodular Polyketide Synthases: Natural Product Biosynthesis Beyond Textbook Assembly Rules. Top Curr Chem (Cham) 2011. [PMID: 21360321 DOI: 10.1007/128_2010_113] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Bacterial multimodular polyketide synthases (PKSs) are responsible for the biosynthesis of a wide range of pharmacologically active natural products. These megaenzymes contain numerous catalytic and structural domains and act as biochemical templates to generate complex polyketides in an assembly line-like fashion. While the prototypical PKS is composed of only a few different domain types that are fused together in a combinatorial fashion, an increasing number of enzymes is being found that contain additional components. These domains can introduce remarkably diverse modifications into polyketides. This review discusses our current understanding of such noncanonical domains and their role in expanding the biosynthetic versatility of bacterial PKSs.
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25
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Pearson L, Mihali T, Moffitt M, Kellmann R, Neilan B. On the chemistry, toxicology and genetics of the cyanobacterial toxins, microcystin, nodularin, saxitoxin and cylindrospermopsin. Mar Drugs 2010; 8:1650-80. [PMID: 20559491 PMCID: PMC2885083 DOI: 10.3390/md8051650] [Citation(s) in RCA: 329] [Impact Index Per Article: 23.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2010] [Revised: 05/02/2010] [Accepted: 05/06/2010] [Indexed: 11/16/2022] Open
Abstract
The cyanobacteria or "blue-green algae", as they are commonly termed, comprise a diverse group of oxygenic photosynthetic bacteria that inhabit a wide range of aquatic and terrestrial environments, and display incredible morphological diversity. Many aquatic, bloom-forming species of cyanobacteria are capable of producing biologically active secondary metabolites, which are highly toxic to humans and other animals. From a toxicological viewpoint, the cyanotoxins span four major classes: the neurotoxins, hepatotoxins, cytotoxins, and dermatoxins (irritant toxins). However, structurally they are quite diverse. Over the past decade, the biosynthesis pathways of the four major cyanotoxins: microcystin, nodularin, saxitoxin and cylindrospermopsin, have been genetically and biochemically elucidated. This review provides an overview of these biosynthesis pathways and additionally summarizes the chemistry and toxicology of these remarkable secondary metabolites.
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Affiliation(s)
- Leanne Pearson
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW, 2052, Australia; E-Mails:
(L.P.);
(T.M.)
| | - Troco Mihali
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW, 2052, Australia; E-Mails:
(L.P.);
(T.M.)
| | - Michelle Moffitt
- School of Biomedical and Health Sciences, The University of Western Sydney, Campbelltown, NSW, 2560, Australia; E-Mail:
(M.M.)
| | - Ralf Kellmann
- Department of Molecular Biology, The University of Bergen, P.O. Box 7803, 5020 Bergen, Norway; E-Mail:
(R.K.)
| | - Brett Neilan
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW, 2052, Australia; E-Mails:
(L.P.);
(T.M.)
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26
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Jones AC, Monroe EA, Eisman EB, Gerwick L, Sherman DH, Gerwick WH. The unique mechanistic transformations involved in the biosynthesis of modular natural products from marine cyanobacteria. Nat Prod Rep 2010; 27:1048-65. [PMID: 20442916 DOI: 10.1039/c000535e] [Citation(s) in RCA: 88] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Cyanobacteria are abundant producers of natural products well recognized for their bioactivity and utility in drug discovery and biotechnology applications. In the last decade, characterization of several modular gene clusters that code for the biosynthesis of these compounds has revealed a number of unusual enzymatic reactions. In this article, we review several mechanistic transformations identified in marine cyanobacterial biosynthetic pathways, with an emphasis on modular polyketide synthase(PKS)/non-ribosomal peptide synthetase (NRPS) gene clusters. In selected instances, we also make comparisons between cyanobacterial gene clusters derived from marine and freshwater strains. We then provide an overview of recent developments in cyanobacterial natural products biosynthesis made available through genome sequencing and new advances in bioinformatics and genetics.
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Affiliation(s)
- Adam C Jones
- Scripps Institution of Oceanography and Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California-San Diego, La Jolla, CA 92093, USA
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27
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Kalaitzis JA, Lauro FM, Neilan BA. Mining cyanobacterial genomes for genes encoding complex biosynthetic pathways. Nat Prod Rep 2009; 26:1447-65. [PMID: 19844640 DOI: 10.1039/b817074f] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Affiliation(s)
- John A Kalaitzis
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW 2052, Australia
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28
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Fewer DP, Jokela J, Rouhiainen L, Wahlsten M, Koskenniemi K, Stal LJ, Sivonen K. The non-ribosomal assembly and frequent occurrence of the protease inhibitors spumigins in the bloom-forming cyanobacteriumNodularia spumigena. Mol Microbiol 2009; 73:924-37. [DOI: 10.1111/j.1365-2958.2009.06816.x] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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29
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Bumpus SB, Kelleher NL. Accessing natural product biosynthetic processes by mass spectrometry. Curr Opin Chem Biol 2009; 12:475-82. [PMID: 18706516 DOI: 10.1016/j.cbpa.2008.07.022] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2008] [Revised: 06/23/2008] [Accepted: 07/17/2008] [Indexed: 11/16/2022]
Abstract
Two important classes of natural products are made by nonribosomal peptide synthetases (NRPSs) and polyketide synthases (PKSs). With most biosynthetic intermediates covalently tethered during biogenesis, protein mass spectrometry (MS) has proven invaluable for their interrogation. New mass spectrometric assay formats (such as selective cofactor ejection and proteomics style LC-MS) are showcased here in the context of functional insights into new breeds of NRPS/PKS enzymes, including the first characterization of an 'iterative' PKS, the biosynthesis of the enediyne antitumor antibiotics, the study of a new strategy for PKS initiation via a GNAT-like mechanism, and the analysis of branching strategies in the so-called 'AT-less' NRPS/PKS hybrid systems. The future of MS analysis of NRPS and PKS biosynthetic pathways lies in adoption and development of methods that continue bridging enzymology with proteomics as both fields continue their post-genomic acceleration.
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Affiliation(s)
- Stefanie B Bumpus
- Department of Chemistry & The Institute for Genomic Biology, University of Illinois Urbana-Champaign, 600 South Mathews Avenue, Urbana, IL 61801, USA
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30
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Plasticity and evolution of aeruginosin biosynthesis in cyanobacteria. Appl Environ Microbiol 2009; 75:2017-26. [PMID: 19201978 DOI: 10.1128/aem.02258-08] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Aeruginosins are bioactive oligopeptides that are produced in high structural diversity by strains of the bloom-forming cyanobacterial genera Microcystis and Planktothrix. A hallmark of aeruginosins is the unusual Choi moiety central to the tetrapeptides, while other positions are occupied by variable moieties in individual congeners. Here we report on three aeruginosin synthetase gene clusters (aer) of Microcystis aeruginosa (strains PCC 7806, NIES-98, and NIES-843). The analysis and comparison the aer gene clusters provide the first insight into the molecular basis of biosynthetic and structural plasticity in aeruginosin pathways. Major parts of the aer gene clusters are highly similar in all strains, particularly the genes coding for the first three nonribosomal peptide synthetase (NRPS) modules except for the region coding for the second adenylation domain. However, the gene clusters differ largely in genes coding for tailoring enzymes such as halogenases and sulfotransferases, reflecting structural peculiarities in aeruginosin congeners produced by the individual strains. Significant deviations were further observed in the C-terminal NRPS modules, suggesting two distinct release mechanisms. The architecture of the gene clusters is in agreement with the particular aeruginosin variants that are produced by individual strains, the structures of two of which (aeruginosins 686 A and 686 B) were elucidated. The aer gene clusters of Microcystis and Planktothrix are proposed to originate from a common ancestor and to have evolved to their present-day diversity largely through horizontal gene transfer and recombination events.
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Pearson LA, Moffitt MC, Ginn HP, B A N. The molecular genetics and regulation of cyanobacterial peptide hepatotoxin biosynthesis. Crit Rev Toxicol 2009; 38:847-56. [PMID: 19012088 DOI: 10.1080/10408440802291513] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Over the last 10 years, we have witnessed major advances in our understanding of natural product biosynthesis, including the genetic basis for toxin production by numerous groups of cyanobacteria. Cyanobacteria produce an unparalleled array of bioactive secondary metabolites, including alkaloids, polyketides and non-ribosomal peptides, some of which are potent toxins. This review addresses the molecular genetics underlying the production of hepatotoxins, microcystin and nodularin in fresh and brackish water. These toxins pose a serious threat to human health and their occurrence in water supplies is increasing, because of the prevalence of toxic algal blooms worldwide. Toxin biosynthesis gene-cluster-associated transposition and the natural transformability of certain species suggest a broader distribution of toxic cyanobacterial taxa. The information gained from the discovery of these toxin biosynthetic pathways has enabled the genetic screening of various environments for drinking-water quality management. Understanding the role of cyanotoxins in the producing microorganisms and the environmental regulation of their biosynthesis genes may also suggest the means of controlling toxic-bloom events.
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Affiliation(s)
- L A Pearson
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, Australia
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32
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Wilkinson B, Micklefield J. Chapter 14. Biosynthesis of nonribosomal peptide precursors. Methods Enzymol 2009; 458:353-78. [PMID: 19374990 DOI: 10.1016/s0076-6879(09)04814-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Nonribosomal peptides are natural products typically of bacterial and fungal origin. These highly complex molecules display a broad spectrum of biological activities, and have been exploited for the development of immunosuppressant, antibiotic, anticancer, and other therapeutic agents. The nonribosomal peptides are assembled by nonribosomal peptide synthetase (NRPS) enzymes comprising repeating modules that are responsible for the sequential selection, activation, and condensation of precursor amino acids. In addition to this, fatty acids, alpha-keto acids and alpha-hydroxy acids, as well as polyketide derived units, can also be utilized by NRPS assembly lines. Final tailoring-steps, including glycosylation and prenylation, serve to further decorate the nonribosomal peptides produced. The wide range of experimental methods that are employed in the elucidation of nonribosomal peptide precursor biosynthesis will be discussed, with particularly emphasis on genomics based approaches which have become wide spread over the last 5 years.
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Affiliation(s)
- Barrie Wilkinson
- Biotica, Chesterford Research Park, Little Chesterford, Essex, United Kingdom
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Ohlendorf B, Leyers S, Krick A, Kehraus S, Wiese M, König GM. Phenylnannolones A-C: Biosynthesis of New Secondary Metabolites from the MyxobacteriumNannocystis exedens. Chembiochem 2008; 9:2997-3003. [DOI: 10.1002/cbic.200800434] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Berlinck RGS, Burtoloso ACB, Kossuga MH. The chemistry and biology of organic guanidine derivatives. Nat Prod Rep 2008; 25:919-54. [DOI: 10.1039/b507874c] [Citation(s) in RCA: 151] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Ishida K, Christiansen G, Yoshida WY, Kurmayer R, Welker M, Valls N, Bonjoch J, Hertweck C, Börner T, Hemscheidt T, Dittmann E. Biosynthesis and structure of aeruginoside 126A and 126B, cyanobacterial peptide glycosides bearing a 2-carboxy-6-hydroxyoctahydroindole moiety. ACTA ACUST UNITED AC 2007; 14:565-576. [PMID: 17524987 PMCID: PMC4020616 DOI: 10.1016/j.chembiol.2007.04.006] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2006] [Revised: 04/02/2007] [Accepted: 04/03/2007] [Indexed: 12/15/2022]
Abstract
Aeruginosins represent a group of peptide metabolites isolated from various cyanobacterial genera and from marine sponges that potently inhibit different types of serine proteases. Members of this family are characterized by the presence of a 2-carboxy-6-hydroxyoctahydroindole (Choi) moiety. We have identified and fully sequenced a NRPS gene cluster in the genome of the cyanobacterium Planktothrix agardhii CYA126/8. Insertional mutagenesis of a NRPS component led to the discovery and structural elucidation of two glycopeptides that were designated aeruginoside 126A and aeruginoside 126B. One variant of the aglycone contains a 1-amino-2-(N-amidino-Delta(3)-pyrrolinyl)ethyl moiety at the C terminus, the other bears an agmatine residue. In silico analyses of the aeruginoside biosynthetic genes aerA-aerI as well as additional mutagenesis and feeding studies allowed the prediction of enzymatic steps leading to the formation of aeruginosides and the unusual Choi moiety.
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Affiliation(s)
- Keishi Ishida
- Humboldt University Berlin, Institute of Biology, 10115 Berlin, Germany
- Leibniz-Institute for Natural Product Research and Infection Biology (HKI) Dept. of Biomolecular Chemistry , 07745 Jena, Germany
| | - Guntram Christiansen
- Humboldt University Berlin, Institute of Biology, 10115 Berlin, Germany
- University of Hawaii at Manoa, Department of Chemistry, Honolulu, Hawaii 96822, USA
| | - Wesley Y. Yoshida
- University of Hawaii at Manoa, Department of Chemistry, Honolulu, Hawaii 96822, USA
| | - Rainer Kurmayer
- Austrian Academy of Science, Institute for Limnology, 5310 Mondsee, Austria
| | - Martin Welker
- Technical University Berlin, Institute of Chemistry, 10587 Berlin, Germany
| | - Nativitat Valls
- University of Barcelona, Faculty of Pharmacy, 08028-Barcelona, Spain
| | - Josep Bonjoch
- University of Barcelona, Faculty of Pharmacy, 08028-Barcelona, Spain
| | - Christian Hertweck
- Leibniz-Institute for Natural Product Research and Infection Biology (HKI) Dept. of Biomolecular Chemistry , 07745 Jena, Germany
| | - Thomas Börner
- Humboldt University Berlin, Institute of Biology, 10115 Berlin, Germany
| | - Thomas Hemscheidt
- University of Hawaii at Manoa, Department of Chemistry, Honolulu, Hawaii 96822, USA
- Cancer Research Center of Hawaii, Honolulu, Hawaii 96813, USA
| | - Elke Dittmann
- Humboldt University Berlin, Institute of Biology, 10115 Berlin, Germany
- Contact: Prof. Dr. Elke Dittmann Tel.: 49-30-20938144 Fax: 49-30-20938141
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Copp JN, Roberts AA, Marahiel MA, Neilan BA. Characterization of PPTNs, a cyanobacterial phosphopantetheinyl transferase from Nodularia spumigena NSOR10. J Bacteriol 2007; 189:3133-9. [PMID: 17307858 PMCID: PMC1855846 DOI: 10.1128/jb.01850-06] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The phosphopantetheinyl transferases (PPTs) are a superfamily of essential enzymes required for the synthesis of a wide range of compounds, including fatty acids, polyketides, and nonribosomal peptide metabolites. These enzymes activate carrier proteins in specific biosynthetic pathways by transfer of a phosphopantetheinyl moiety. The diverse PPT superfamily can be divided into two families based on specificity and conserved sequence motifs. The first family is typified by the Escherichia coli acyl carrier protein synthase (AcpS), which is involved in fatty acid synthesis. The prototype of the second family is the broad-substrate-range PPT Sfp, which is required for surfactin biosynthesis in Bacillus subtilis. Most cyanobacteria do not encode an AcpS-like PPT, and furthermore, some of their Sfp-like PPTs belong to a unique phylogenetic subgroup defined by the PPTs involved in heterocyst differentiation. Here, we describe the first functional characterization of a cyanobacterial PPT based on a structural analysis and subsequent functional analysis of the Nodularia spumigena NSOR10 PPT. Southern hybridizations suggested that this enzyme may be the only PPT encoded in the N. spumigena NSOR10 genome. Expression and enzyme characterization showed that this PPT was capable of modifying carrier proteins resulting from both heterocyst glycoplipid synthesis and nodularin toxin synthesis. Cyanobacteria are a unique and vast source of bioactive metabolites; therefore, an understanding of cyanobacterial PPTs is important in order to harness the biotechnological potential of cyanobacterial natural products.
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Affiliation(s)
- J N Copp
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Kensington NSW 2052, Sydney, Australia
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Van Wagoner RM, Drummond AK, Wright JLC. Biogenetic Diversity of Cyanobacterial Metabolites. ADVANCES IN APPLIED MICROBIOLOGY 2007; 61:89-217. [PMID: 17448789 DOI: 10.1016/s0065-2164(06)61004-6] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Affiliation(s)
- Ryan M Van Wagoner
- Center for Marine Science, University of North Carolina at Wilmington, Wilmington, NC 28409, USA
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Magarvey NA, Beck ZQ, Golakoti T, Ding Y, Huber U, Hemscheidt TK, Abelson D, Moore RE, Sherman DH. Biosynthetic characterization and chemoenzymatic assembly of the cryptophycins. Potent anticancer agents from cyanobionts. ACS Chem Biol 2006; 1:766-79. [PMID: 17240975 DOI: 10.1021/cb6004307] [Citation(s) in RCA: 113] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The lichen cyanobacterial symbiont Nostoc sp. ATCC 53789 and its close relative Nostoc sp. GSV 224 are prolific producers of natural products, generating >25 derivatives of the cryptophycin class of secondary metabolites. Cryptophycin 1, the prototypic member of the class, is a potent tubulin-depolymerizing agent, and several semisynthetic derivatives are being developed as anticancer therapeutics. Here we provide a detailed characterization of the cryptophycin metabolic pathway by stable-isotope labeling experiments and through cloning, sequencing, and annotating the cryptophycin biosynthetic gene cluster. A comparative secondary metabolomic analysis based on polyketide (PK)/non-ribosomal peptide gene clusters from the phylogenetically related, non-cryptophycin producing cycad symbiont, Nostoc punctiforme ATCC 29133, was used to identify the cryptophycin biosynthetic genes that encompass approximately 40 kb within the lichen symbiont Nostoc sp. ATCC 53789 genome. The pathway encodes a collinear set of enzymes, including three modular PK synthases, two non-ribosomal peptide synthetase modules, and an integrated adenylation/ketoreductase didomain for elaboration of the leucic acid subunit. In addition, genes encoding key tailoring steps, including a FAD-dependent halogenase and CYP450 epoxidase, were identified. The inherent flexibility of the cryptophycin biosynthetic enzymes was harnessed to generate a suite of new analogues by altering the pool of PK starter units and selected amino acid extender groups. Characterization of the cryptophycin CYP450 enabled development of the first stereospecific synthesis of cryptophycin 2, through a tandem chemoenzymatic synthesis from the natural seco-cryptophycin 4 chain elongation intermediate.
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Affiliation(s)
- Nathan A Magarvey
- Department of Microbiology and BioTechnology Institute, University of Minnesota, Minneapolis-St. Paul, Minnesota 55108, USA
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Dorrestein PC, Bumpus SB, Calderone CT, Garneau-Tsodikova S, Aron ZD, Straight PD, Kolter R, Walsh CT, Kelleher NL. Facile detection of acyl and peptidyl intermediates on thiotemplate carrier domains via phosphopantetheinyl elimination reactions during tandem mass spectrometry. Biochemistry 2006; 45:12756-66. [PMID: 17042494 PMCID: PMC2518290 DOI: 10.1021/bi061169d] [Citation(s) in RCA: 126] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
With the emergence of drug resistance and the genomic revolution, there has been a renewed interest in the genes that are responsible for the generation of bioactive natural products. Secondary metabolites of one major class are biosynthesized at one or more sites by ultralarge enzymes that carry covalent intermediates on phosphopantetheine arms. Because such intermediates are difficult to characterize in vitro, we have developed a new approach for streamlined detection of substrates, intermediates, and products attached to a phosphopantetheinyl arm of the carrier site. During vibrational activation of gas-phase carrier domains, facile elimination occurs in benchtop and Fourier-transform mass spectrometers alike. Phosphopantetheinyl ejections quickly reduce >100 kDa megaenzymes to <1000 Da ions for structural assignment of intermediates at <0.007 Da mass accuracy without proteolytic digestion. This "top down" approach quickly illuminated diverse acyl intermediates on the carrier domains of the nonribosomal peptide synthetases (NRPSs) or polyketide synthases (PKSs) found in the biosynthetic pathways of prodigiosin, pyoluteorin, mycosubtilin, nikkomycin, enterobactin, gramicidin, and several proteins from the orphan pksX gene cluster from Bacillus subtilis. By focusing on just those regions undergoing covalent chemistry, the method delivered clean proof for the reversible dehydration of hydroxymethylglutaryl-S-PksL via incorporation of 2H or 18O from the buffer. The facile nature of this revised assay will allow diverse laboratories to spearhead their NRPS-PKS projects with benchtop mass spectrometers.
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Affiliation(s)
- Pieter C. Dorrestein
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL, 600 S. Mathews Ave. 61801
| | - Stefanie B. Bumpus
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL, 600 S. Mathews Ave. 61801
| | - Christopher T. Calderone
- Department of Biological Chemistry & Molecular Pharmacology, Harvard Medical School, Boston, MA 02115
| | - Sylvie Garneau-Tsodikova
- Department of Biological Chemistry & Molecular Pharmacology, Harvard Medical School, Boston, MA 02115
| | - Zachary D. Aron
- Department of Biological Chemistry & Molecular Pharmacology, Harvard Medical School, Boston, MA 02115
| | - Paul D. Straight
- Department of Microbiology and Molecular Genetics, Harvard Medical School, Boston, MA 02115
| | - Roberto Kolter
- Department of Microbiology and Molecular Genetics, Harvard Medical School, Boston, MA 02115
| | - Christopher T. Walsh
- Department of Biological Chemistry & Molecular Pharmacology, Harvard Medical School, Boston, MA 02115
| | - Neil L. Kelleher
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL, 600 S. Mathews Ave. 61801
- Corresponding author: , Fax 217−244−8068, Phone 217−244−3927. Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL, 600 S. Mathews Ave. 61801
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