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Ray KA, Lutgens JD, Bista R, Zhang J, Desai RR, Hirsch M, Miyazawa T, Cordova A, Keatinge-Clay AT. Assessing and harnessing updated polyketide synthase modules through combinatorial engineering. Nat Commun 2024; 15:6485. [PMID: 39090122 PMCID: PMC11294587 DOI: 10.1038/s41467-024-50844-6] [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: 07/24/2023] [Accepted: 07/23/2024] [Indexed: 08/04/2024] Open
Abstract
The modular nature of polyketide assembly lines and the significance of their products make them prime targets for combinatorial engineering. The recently updated module boundary has been successful for engineering short synthases, yet larger synthases constructed using the updated boundary have not been investigated. Here we describe our design and implementation of a BioBricks-like platform to rapidly construct 5 triketide, 25 tetraketide, and 125 pentaketide synthases to test every module combination of the pikromycin synthase. Anticipated products are detected from 60% of the triketide synthases, 32% of the tetraketide synthases, and 6.4% of the pentaketide synthases. We determine ketosynthase gatekeeping and module-skipping are the principal impediments to obtaining functional synthases. The platform is also employed to construct active hybrid synthases by incorporating modules from the erythromycin, spinosyn, and rapamycin assembly lines. The relaxed gatekeeping of a ketosynthase in the rapamycin synthase is especially encouraging in the quest to produce designer polyketides.
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Affiliation(s)
- Katherine A Ray
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX, USA
| | - Joshua D Lutgens
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX, USA
| | - Ramesh Bista
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX, USA
| | - Jie Zhang
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX, USA
| | - Ronak R Desai
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX, USA
| | - Melissa Hirsch
- Department of Chemistry, The University of Texas at Austin, Austin, TX, USA
| | - Takeshi Miyazawa
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX, USA
| | - Antonio Cordova
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX, USA
| | - Adrian T Keatinge-Clay
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX, USA.
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2
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Kim M, Bae M, Jung Y, Kim JM, Hwang S, Song MC, Ban YH, Bae ES, Hong S, Lee SK, Cha S, Oh D, Yoon YJ. Unprecedented Noncanonical Features of the Nonlinear Nonribosomal Peptide Synthetase Assembly Line for WS9326A Biosynthesis. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202103872] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Myoun‐Su Kim
- Natural Products Research Institute College of Pharmacy Seoul National University 1 Gwanak-ro, Gwanak-gu Seoul 08826 Republic of Korea
| | - Munhyung Bae
- Natural Products Research Institute College of Pharmacy Seoul National University 1 Gwanak-ro, Gwanak-gu Seoul 08826 Republic of Korea
| | - Ye‐Eun Jung
- Department of Chemistry and Nanoscience Ewha Womans University 52 Ewhayeodae-gil, Seodaemun-gu Seoul 03760 Republic of Korea
| | - Jung Min Kim
- Natural Products Research Institute College of Pharmacy Seoul National University 1 Gwanak-ro, Gwanak-gu Seoul 08826 Republic of Korea
| | - Sunghoon Hwang
- Natural Products Research Institute College of Pharmacy Seoul National University 1 Gwanak-ro, Gwanak-gu Seoul 08826 Republic of Korea
| | - Myoung Chong Song
- Natural Products Research Institute College of Pharmacy Seoul National University 1 Gwanak-ro, Gwanak-gu Seoul 08826 Republic of Korea
| | - Yeon Hee Ban
- Natural Products Research Institute College of Pharmacy Seoul National University 1 Gwanak-ro, Gwanak-gu Seoul 08826 Republic of Korea
| | - Eun Seo Bae
- Natural Products Research Institute College of Pharmacy Seoul National University 1 Gwanak-ro, Gwanak-gu Seoul 08826 Republic of Korea
| | - Suckchang Hong
- Research Institute of Pharmaceutical Sciences College of Pharmacy Seoul National University 1 Gwanak-ro, Gwanak-gu Seoul 08826 Republic of Korea
| | - Sang Kook Lee
- Natural Products Research Institute College of Pharmacy Seoul National University 1 Gwanak-ro, Gwanak-gu Seoul 08826 Republic of Korea
| | - Sun‐Shin Cha
- Department of Chemistry and Nanoscience Ewha Womans University 52 Ewhayeodae-gil, Seodaemun-gu Seoul 03760 Republic of Korea
| | - Dong‐Chan Oh
- Natural Products Research Institute College of Pharmacy Seoul National University 1 Gwanak-ro, Gwanak-gu Seoul 08826 Republic of Korea
| | - Yeo Joon Yoon
- Natural Products Research Institute College of Pharmacy Seoul National University 1 Gwanak-ro, Gwanak-gu Seoul 08826 Republic of Korea
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3
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Kim M, Bae M, Jung Y, Kim JM, Hwang S, Song MC, Ban YH, Bae ES, Hong S, Lee SK, Cha S, Oh D, Yoon YJ. Unprecedented Noncanonical Features of the Nonlinear Nonribosomal Peptide Synthetase Assembly Line for WS9326A Biosynthesis. Angew Chem Int Ed Engl 2021; 60:19766-19773. [DOI: 10.1002/anie.202103872] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Revised: 05/04/2021] [Indexed: 12/21/2022]
Affiliation(s)
- Myoun‐Su Kim
- Natural Products Research Institute College of Pharmacy Seoul National University 1 Gwanak-ro, Gwanak-gu Seoul 08826 Republic of Korea
| | - Munhyung Bae
- Natural Products Research Institute College of Pharmacy Seoul National University 1 Gwanak-ro, Gwanak-gu Seoul 08826 Republic of Korea
| | - Ye‐Eun Jung
- Department of Chemistry and Nanoscience Ewha Womans University 52 Ewhayeodae-gil, Seodaemun-gu Seoul 03760 Republic of Korea
| | - Jung Min Kim
- Natural Products Research Institute College of Pharmacy Seoul National University 1 Gwanak-ro, Gwanak-gu Seoul 08826 Republic of Korea
| | - Sunghoon Hwang
- Natural Products Research Institute College of Pharmacy Seoul National University 1 Gwanak-ro, Gwanak-gu Seoul 08826 Republic of Korea
| | - Myoung Chong Song
- Natural Products Research Institute College of Pharmacy Seoul National University 1 Gwanak-ro, Gwanak-gu Seoul 08826 Republic of Korea
| | - Yeon Hee Ban
- Natural Products Research Institute College of Pharmacy Seoul National University 1 Gwanak-ro, Gwanak-gu Seoul 08826 Republic of Korea
| | - Eun Seo Bae
- Natural Products Research Institute College of Pharmacy Seoul National University 1 Gwanak-ro, Gwanak-gu Seoul 08826 Republic of Korea
| | - Suckchang Hong
- Research Institute of Pharmaceutical Sciences College of Pharmacy Seoul National University 1 Gwanak-ro, Gwanak-gu Seoul 08826 Republic of Korea
| | - Sang Kook Lee
- Natural Products Research Institute College of Pharmacy Seoul National University 1 Gwanak-ro, Gwanak-gu Seoul 08826 Republic of Korea
| | - Sun‐Shin Cha
- Department of Chemistry and Nanoscience Ewha Womans University 52 Ewhayeodae-gil, Seodaemun-gu Seoul 03760 Republic of Korea
| | - Dong‐Chan Oh
- Natural Products Research Institute College of Pharmacy Seoul National University 1 Gwanak-ro, Gwanak-gu Seoul 08826 Republic of Korea
| | - Yeo Joon Yoon
- Natural Products Research Institute College of Pharmacy Seoul National University 1 Gwanak-ro, Gwanak-gu Seoul 08826 Republic of Korea
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4
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Pass-back chain extension expands multimodular assembly line biosynthesis. Nat Chem Biol 2019; 16:42-49. [PMID: 31636431 PMCID: PMC6917876 DOI: 10.1038/s41589-019-0385-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Accepted: 09/06/2019] [Indexed: 11/26/2022]
Abstract
Modular nonribosomal peptide synthetase (NRPS) and polyketide synthase (PKS) enzymatic assembly lines are large and dynamic protein machines that generally effect a linear sequence of catalytic cycles. Here we report the heterologous reconstitution and comprehensive characterization of two hybrid NRPS-PKS assembly lines that defy many standard rules of assembly line biosynthesis to generate a large combinatorial library of cyclic lipodepsipeptide protease inhibitors called thalassospiramides. We generate a series of precise domain-inactivating mutations in thalassospiramide assembly lines and present evidence for an unprecedented biosynthetic model that invokes inter-module substrate activation and tailoring, module skipping, and pass-back chain extension, whereby the ability to pass the growing chain back to a preceding module is flexible and substrate-driven. Expanding bidirectional inter-module domain interactions could represent a viable mechanism for generating chemical diversity without increasing the size of biosynthetic assembly lines and challenges our understanding of the potential elasticity of multi-modular megaenzymes.
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5
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A dual transacylation mechanism for polyketide synthase chain release in enacyloxin antibiotic biosynthesis. Nat Chem 2019; 11:906-912. [PMID: 31548673 PMCID: PMC6774797 DOI: 10.1038/s41557-019-0309-7] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Accepted: 07/12/2019] [Indexed: 01/24/2023]
Abstract
Polyketide synthases assemble diverse natural products with numerous important applications. The thioester intermediates in polyketide assembly are covalently tethered to acyl carrier protein domains of the synthase. Several mechanisms for polyketide chain release are known, contributing to natural product structural diversification. Here we report a dual transacylation mechanism for chain release from the enacyloxin polyketide synthase, which assembles an antibiotic with promising activity against Acinetobacter baumannii. A non-elongating ketosynthase domain transfers the polyketide chain from the final acyl carrier protein domain of the synthase to a separate carrier protein and a nonribosomal peptide synthetase condensation domain condenses it with (1S, 3R, 4S)-3, 4-dihydroxycyclohexane carboxylic acid. Molecular dissection of this process reveals that non-elongating ketosynthase domain-mediated transacylation circumvents the inability of the condensation domain to recognize the acyl carrier protein domain. Several 3, 4-dihydroxycyclohexane carboxylic acid analogues can be employed for chain release, suggesting a promising strategy for producing enacyloxin analogues.
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Emulating evolutionary processes to morph aureothin-type modular polyketide synthases and associated oxygenases. Nat Commun 2019; 10:3918. [PMID: 31477708 PMCID: PMC6718629 DOI: 10.1038/s41467-019-11896-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Accepted: 08/12/2019] [Indexed: 12/17/2022] Open
Abstract
Polyketides produced by modular type I polyketide synthases (PKSs) play eminent roles in the development of medicines. Yet, the production of structural analogs by genetic engineering poses a major challenge. We report an evolution-guided morphing of modular PKSs inspired by recombination processes that lead to structural diversity in nature. By deletion and insertion of PKS modules we interconvert the assembly lines for related antibiotic and antifungal agents, aureothin (aur) and neoaureothin (nor) (aka spectinabilin), in both directions. Mutational and functional analyses of the polyketide-tailoring cytochrome P450 monooxygenases, and PKS phylogenies give contradictory clues on potential evolutionary scenarios (generalist-to-specialist enzyme evolution vs. most parsimonious ancestor). The KS-AT linker proves to be well suited as fusion site for both excision and insertion of modules, which supports a model for alternative module boundaries in some PKS systems. This study teaches important lessons on the evolution of PKSs, which may guide future engineering approaches. The wealth of complex polyketides is an essential source for drug discovery. Here, the authors report an evolution-guided rational morphing of modular polyketide synthases (PKSs) for aurothin and neoaurothin biosynthesis, and reveal engineering site suitable for diversifying PKS systems.
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7
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Musiol-Kroll EM, Wohlleben W. Acyltransferases as Tools for Polyketide Synthase Engineering. Antibiotics (Basel) 2018; 7:antibiotics7030062. [PMID: 30022008 PMCID: PMC6164871 DOI: 10.3390/antibiotics7030062] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2018] [Revised: 07/14/2018] [Accepted: 07/16/2018] [Indexed: 12/16/2022] Open
Abstract
Polyketides belong to the most valuable natural products, including diverse bioactive compounds, such as antibiotics, anticancer drugs, antifungal agents, immunosuppressants and others. Their structures are assembled by polyketide synthases (PKSs). Modular PKSs are composed of modules, which involve sets of domains catalysing the stepwise polyketide biosynthesis. The acyltransferase (AT) domains and their “partners”, the acyl carrier proteins (ACPs), thereby play an essential role. The AT loads the building blocks onto the “substrate acceptor”, the ACP. Thus, the AT dictates which building blocks are incorporated into the polyketide structure. The precursor- and occasionally the ACP-specificity of the ATs differ across the polyketide pathways and therefore, the ATs contribute to the structural diversity within this group of complex natural products. Those features make the AT enzymes one of the most promising tools for manipulation of polyketide assembly lines and generation of new polyketide compounds. However, the AT-based PKS engineering is still not straightforward and thus, rational design of functional PKSs requires detailed understanding of the complex machineries. This review summarizes the attempts of PKS engineering by exploiting the AT attributes for the modification of polyketide structures. The article includes 253 references and covers the most relevant literature published until May 2018.
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Affiliation(s)
- Ewa Maria Musiol-Kroll
- Interfakultäres Institut für Mikrobiologie und Infektionsmedizin, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 28, 72076 Tübingen, Germany.
| | - Wolfgang Wohlleben
- Interfakultäres Institut für Mikrobiologie und Infektionsmedizin, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 28, 72076 Tübingen, Germany.
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8
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Gao L, Guo J, Fan Y, Ma Z, Lu Z, Zhang C, Zhao H, Bie X. Module and individual domain deletions of NRPS to produce plipastatin derivatives in Bacillus subtilis. Microb Cell Fact 2018; 17:84. [PMID: 29855381 PMCID: PMC5984369 DOI: 10.1186/s12934-018-0929-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Accepted: 05/11/2018] [Indexed: 12/04/2022] Open
Abstract
Background Plipastatin, an antifungal lipopeptide, is synthesized by a non-ribosomal peptide synthetase (NRPS) in Bacillus subtilis. However, little information is available on the combinatorial biosynthesis strategies applied in plipastatin biosynthetic pathway. In this study, we applied module or individual domain deletion strategies to engineer the plipastatin biosynthetic pathway, and investigated the effect of deletions on the plipastatin assembly line, as well as revealed the synthetic patterns of novel lipopeptides. Results Module deletion inactivated the entire enzyme complex, whereas individual domain (A/T domain) deletion within module 7 truncated the assembly line, resulting in truncated linear hexapeptides (C16~17β-OHFA-Glu-Orn-Tyr-Thr-Glu-Ala/Val). Interestingly, within the module 6 catalytic unit, the effect of thiolation domain deletion differed from that of adenylation deletion. Absence of the T6-domain resulted in a nonproductive strain, whereas deletion of the A6-domain resulted in multiple assembly lines via module-skipping mechanism, generating three novel types of plipastatin derivatives, pentapeptides (C16~17β-OHFA-Glu-Orn-Tyr-Thr-Glu), hexapeptides (C16~17β-OHFA-Glu-Orn-Tyr-Thr-Glu-Ile), and octapeptides (C16~17β-OHFA-Glu-Orn-Tyr-Thr-Glu-Gln-Tyr-Ile). Conclusions Notably, a unique module-skipping process occurred following deletion of the A6-domain, which has not been previously reported for engineered NRPS systems. This finding provides new insight into the lipopeptides engineering. It is of significant importance for combinatorial approaches and should be taken into consideration in engineering non-ribosomal peptide biosynthetic pathways for generating novel lipopeptides. Electronic supplementary material The online version of this article (10.1186/s12934-018-0929-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Ling Gao
- College of Food Science and Technology, Nanjing Agricultural University, 1 Weigang, Nanjing, 210095, People's Republic of China
| | - Jianping Guo
- College of Food Science and Technology, Nanjing Agricultural University, 1 Weigang, Nanjing, 210095, People's Republic of China
| | - Yun Fan
- College of Food Science and Technology, Nanjing Agricultural University, 1 Weigang, Nanjing, 210095, People's Republic of China
| | - Zhi Ma
- College of Food Science and Technology, Nanjing Agricultural University, 1 Weigang, Nanjing, 210095, People's Republic of China
| | - Zhaoxin Lu
- College of Food Science and Technology, Nanjing Agricultural University, 1 Weigang, Nanjing, 210095, People's Republic of China
| | - Chong Zhang
- College of Food Science and Technology, Nanjing Agricultural University, 1 Weigang, Nanjing, 210095, People's Republic of China
| | - Haizhen Zhao
- College of Food Science and Technology, Nanjing Agricultural University, 1 Weigang, Nanjing, 210095, People's Republic of China
| | - Xiaomei Bie
- College of Food Science and Technology, Nanjing Agricultural University, 1 Weigang, Nanjing, 210095, People's Republic of China.
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9
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Shishido TK, Jokela J, Fewer DP, Wahlsten M, Fiore MF, Sivonen K. Simultaneous Production of Anabaenopeptins and Namalides by the Cyanobacterium Nostoc sp. CENA543. ACS Chem Biol 2017; 12:2746-2755. [PMID: 28933529 DOI: 10.1021/acschembio.7b00570] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Anabaenopeptins are a diverse group of cyclic peptides, which contain an unusual ureido linkage. Namalides are shorter structural homologues of anabaenopeptins, which also contain an ureido linkage. The biosynthetic origins of namalides are unknown despite a strong resemblance to anabaenopeptins. Here, we show the cyanobacterium Nostoc sp. CENA543 strain producing new (nostamide B-E (2, 4, 5, and 6)) and known variants of anabaenopeptins (schizopeptin 791 (1) and anabaenopeptin 807 (3)). Surprisingly, Nostoc sp. CENA543 also produced namalide B (8) and the new namalides D (7), E (9), and F (10) in similar amounts to anabaenopeptins. Analysis of the complete Nostoc sp. CENA543 genome sequence indicates that both anabaenopeptins and namalides are produced by the same biosynthetic pathway through module skipping during biosynthesis. This unique process involves the skipping of two modules present in different nonribosomal peptide synthetases during the namalide biosynthesis. This skipping is an efficient mechanism since both anabaenopeptins and namalides are synthesized in similar amounts by Nostoc sp. CENA543. Consequently, gene skipping may be used to increase and possibly broaden the chemical diversity of related peptides produced by a single biosynthetic gene cluster. Genome mining demonstrated that the anabaenopeptin gene clusters are widespread in cyanobacteria and can also be found in tectomicrobia bacteria.
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Affiliation(s)
- Tânia K. Shishido
- Department
of Food and Environmental Sciences, University of Helsinki, Viikki Biocenter 1, P.O. Box 56, 00014 Helsinki, Finland
| | - Jouni Jokela
- Department
of Food and Environmental Sciences, University of Helsinki, Viikki Biocenter 1, P.O. Box 56, 00014 Helsinki, Finland
| | - David P. Fewer
- Department
of Food and Environmental Sciences, University of Helsinki, Viikki Biocenter 1, P.O. Box 56, 00014 Helsinki, Finland
| | - Matti Wahlsten
- Department
of Food and Environmental Sciences, University of Helsinki, Viikki Biocenter 1, P.O. Box 56, 00014 Helsinki, Finland
| | - Marli F. Fiore
- Center
for Nuclear Energy in Agriculture, University of São Paulo, Avenida Centenário 303, Piracicaba, 13400-970, São Paulo, Brazil
| | - Kaarina Sivonen
- Department
of Food and Environmental Sciences, University of Helsinki, Viikki Biocenter 1, P.O. Box 56, 00014 Helsinki, Finland
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10
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Zarins-Tutt JS, Abraham ER, Bailey CS, Goss RJM. Bluegenics: Bioactive Natural Products of Medicinal Relevance and Approaches to Their Diversification. PROGRESS IN MOLECULAR AND SUBCELLULAR BIOLOGY 2017; 55:159-186. [PMID: 28238038 DOI: 10.1007/978-3-319-51284-6_5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Nature provides a valuable resource of medicinally relevant compounds, with many antimicrobial and antitumor agents entering clinical trials being derived from natural products. The generation of analogues of these bioactive natural products is important in order to gain a greater understanding of structure activity relationships; probing the mechanism of action, as well as to optimise the natural product's bioactivity and bioavailability. This chapter critically examines different approaches to generating natural products and their analogues, exploring the way in which synthetic and biosynthetic approaches may be blended together to enable expeditious access to new designer natural products.
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Affiliation(s)
| | - Emily R Abraham
- School of Chemistry, University of St Andrews, St Andrews, Scotland, UK
| | | | - Rebecca J M Goss
- School of Chemistry, University of St Andrews, St Andrews, Scotland, UK.
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11
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Bayly CL, Yadav VG. Towards Precision Engineering of Canonical Polyketide Synthase Domains: Recent Advances and Future Prospects. Molecules 2017; 22:molecules22020235. [PMID: 28165430 PMCID: PMC6155766 DOI: 10.3390/molecules22020235] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Revised: 01/10/2017] [Accepted: 01/11/2017] [Indexed: 01/09/2023] Open
Abstract
Modular polyketide synthases (mPKSs) build functionalized polymeric chains, some of which have become blockbuster therapeutics. Organized into repeating clusters (modules) of independently-folding domains, these assembly-line-like megasynthases can be engineered by introducing non-native components. However, poor introduction points and incompatible domain combinations can cause both unintended products and dramatically reduced activity. This limits the engineering and combinatorial potential of mPKSs, precluding access to further potential therapeutics. Different regions on a given mPKS domain determine how it interacts both with its substrate and with other domains. Within the assembly line, these interactions are crucial to the proper ordering of reactions and efficient polyketide construction. Achieving control over these domain functions, through precision engineering at key regions, would greatly expand our catalogue of accessible polyketide products. Canonical mPKS domains, given that they are among the most well-characterized, are excellent candidates for such fine-tuning. The current minireview summarizes recent advances in the mechanistic understanding and subsequent precision engineering of canonical mPKS domains, focusing largely on developments in the past year.
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Affiliation(s)
- Carmen L Bayly
- Department of Genome Sciences & Technology, The University of British Columbia, Vancouver, BC V5Z 4S6, Canada.
- Department of Chemical & Biological Engineering, The University of British Columbia, Vancouver, BC V6T 1Z3, Canada.
| | - Vikramaditya G Yadav
- Department of Chemical & Biological Engineering, The University of British Columbia, Vancouver, BC V6T 1Z3, Canada.
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12
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Translocation of the thioesterase domain for the redesign of plipastatin synthetase. Sci Rep 2016; 6:38467. [PMID: 28009004 PMCID: PMC5180189 DOI: 10.1038/srep38467] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Accepted: 11/09/2016] [Indexed: 11/23/2022] Open
Abstract
Non-ribosomal peptide synthetases (NRPSs) are large enzymatic complexes that catalyse the synthesis of biologically active peptides in microorganisms. Genetic engineering has recently been applied to reprogram NRPSs to produce lipopeptides with a new sequence. The carboxyl-terminal thioesterase (TE) domains from NRPSs catalyse cleavage products by hydrolysis or complex macrocyclization. In this study, we modified plipastatin synthetase by moving the intrinsic TE region to the end of the internal thiolation (T) domains, thus generating Bacillus subtilis strains that could produce new truncated cyclic or linear peptides of the predicted sequence, which further provided an important insight into the regioselectivity of plipastatin TE. The TE was capable of recognizing and catalysing the lactone formation between L-Try3 with the last few residues L-Pro7 and L-Gln8 at the C-terminus. Additionally, the unmatched linkers connecting the TE region and T domain resulted in nonproduction strains, suggesting that the native T–TE linker is necessary and sufficient for the TE domain to release the products from the hybrid enzymes. This is the first report to demonstrate truncated cyclic lipopeptides production and module skipping by simply moving the TE domain forward in an NRPS system.
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13
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Hong H, Sun Y, Zhou Y, Stephens E, Samborskyy M, Leadlay PF. Evidence for an iterative module in chain elongation on the azalomycin polyketide synthase. Beilstein J Org Chem 2016; 12:2164-2172. [PMID: 27829923 PMCID: PMC5082578 DOI: 10.3762/bjoc.12.206] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Accepted: 09/23/2016] [Indexed: 11/28/2022] Open
Abstract
The assembly-line synthases that produce bacterial polyketide natural products follow a modular paradigm in which each round of chain extension is catalysed by a different set or module of enzymes. Examples of deviation from this paradigm, in which a module catalyses either multiple extensions or none are of interest from both a mechanistic and an evolutionary viewpoint. We present evidence that in the biosynthesis of the 36-membered macrocyclic aminopolyol lactones (marginolactones) azalomycin and kanchanamycin, isolated respectively from Streptomyces malaysiensis DSM4137 and Streptomyces olivaceus Tü4018, the first extension module catalyses both the first and second cycles of polyketide chain extension. To confirm the integrity of the azl gene cluster, it was cloned intact on a bacterial artificial chromosome and transplanted into the heterologous host strain Streptomyces lividans, which does not possess the genes for marginolactone production. When furnished with 4-guanidinobutyramide, a specific precursor of the azalomycin starter unit, the recombinant S. lividans produced azalomycin, showing that the polyketide synthase genes in the sequenced cluster are sufficient to accomplish formation of the full-length polyketide chain. This provides strong support for module iteration in the azalomycin and kanchanamycin biosynthetic pathways. In contrast, re-sequencing of the gene cluster for biosynthesis of the polyketide β-lactone ebelactone in Streptomyces aburaviensis has shown that, contrary to a recently-published proposal, the ebelactone polyketide synthase faithfully follows the colinear modular paradigm.
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Affiliation(s)
- Hui Hong
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge, CB2 1GA, United Kingdom
| | - Yuhui Sun
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, Wuhan University, Ministry of Education, and Wuhan University School of Pharmaceutical Sciences, Wuhan 430071, People’s Republic of China
| | - Yongjun Zhou
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge, CB2 1GA, United Kingdom
| | - Emily Stephens
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge, CB2 1GA, United Kingdom
| | - Markiyan Samborskyy
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge, CB2 1GA, United Kingdom
| | - Peter F Leadlay
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge, CB2 1GA, United Kingdom
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14
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Lin Z, Chen D, Liu W. Biosynthesis-based artificial evolution of microbial natural products. Sci China Chem 2016. [DOI: 10.1007/s11426-016-0062-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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15
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Tang XL, Dai P, Gao H, Wang CX, Chen GD, Hong K, Hu D, Yao XS. A Single Gene Cluster for Chalcomycins and Aldgamycins: Genetic Basis for Bifurcation of Their Biosynthesis. Chembiochem 2016; 17:1241-9. [PMID: 27191535 DOI: 10.1002/cbic.201600118] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2016] [Indexed: 01/27/2023]
Abstract
Aldgamycins are 16-membered macrolide antibiotics with a rare branched-chain sugar d-aldgarose or decarboxylated d-aldgarose at C-5. In our efforts to clone the gene cluster for aldgamycins from a marine-derived Streptomyces sp. HK-2006-1 capable of producing both aldgamycins and chalcomycins, we found that both are biosynthesized from a single gene cluster. Whole-genome sequencing combined with gene disruption established the entire gene cluster of aldgamycins: nine new genes are incorporated with the previously identified chalcomycin gene cluster. Functional analysis of these genes revealed that almDI/almDII, (encoding α/β subunits of pyruvate dehydrogenase) triggers the biosynthesis of aldgamycins, whereas almCI (encoding an oxidoreductase) initiates chalcomycins biosynthesis. This is the first report that aldgamycins and chalcomycins are derived from a single gene cluster and of the genetic basis for bifurcation in their biosynthesis.
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Affiliation(s)
- Xiao-Long Tang
- College of Traditional Chinese Materia Medica, Shenyang Pharmaceutical University, No. 103 Wenhua Road, Shenyang, 110016, China
| | - Ping Dai
- Institute of Traditional Chinese Medicine and Natural Products, College of Pharmacy, Jinan University, No. 601 Huangpu Avenue, Guangzhou, 510632, China
| | - Hao Gao
- Institute of Traditional Chinese Medicine and Natural Products, College of Pharmacy, Jinan University, No. 601 Huangpu Avenue, Guangzhou, 510632, China
| | - Chuan-Xi Wang
- Institute of Traditional Chinese Medicine and Natural Products, College of Pharmacy, Jinan University, No. 601 Huangpu Avenue, Guangzhou, 510632, China
| | - Guo-Dong Chen
- Institute of Traditional Chinese Medicine and Natural Products, College of Pharmacy, Jinan University, No. 601 Huangpu Avenue, Guangzhou, 510632, China
| | - Kui Hong
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, Ministry of Education, School of Pharmaceutical Sciences, Wuhan University, No. 185 Donghu Road, Wuhan, 430071, China
| | - Dan Hu
- Institute of Traditional Chinese Medicine and Natural Products, College of Pharmacy, Jinan University, No. 601 Huangpu Avenue, Guangzhou, 510632, China.
| | - Xin-Sheng Yao
- College of Traditional Chinese Materia Medica, Shenyang Pharmaceutical University, No. 103 Wenhua Road, Shenyang, 110016, China. .,Institute of Traditional Chinese Medicine and Natural Products, College of Pharmacy, Jinan University, No. 601 Huangpu Avenue, Guangzhou, 510632, China.
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16
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Weissman KJ. Genetic engineering of modular PKSs: from combinatorial biosynthesis to synthetic biology. Nat Prod Rep 2016; 33:203-30. [DOI: 10.1039/c5np00109a] [Citation(s) in RCA: 115] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
This reviews covers on-going efforts at engineering the gigantic modular polyketide synthases (PKSs), highlighting both notable successes and failures.
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Affiliation(s)
- Kira J. Weissman
- UMR 7365
- Ingénierie Moléculaire et Physiopathologie Articulaire (IMoPA)
- CNRS-Université de Lorraine
- Biopôle de l'Université de Lorraine
- 54505 Vandœuvre-lès-Nancy Cedex
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17
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Abstract
This review covers a breakthrough in the structural biology of the gigantic modular polyketide synthases (PKS): the structural characterization of intact modules by single-particle cryo-electron microscopy and small-angle X-ray scattering.
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Affiliation(s)
- Kira J. Weissman
- Molecular and Structural Enzymology Group
- Université de Lorraine
- IMoPA
- UMR 7365
- Vandœuvre-lès-Nancy
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18
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He HY, Tang MC, Zhang F, Tang GL. Cis-Double Bond Formation by Thioesterase and Transfer by Ketosynthase in FR901464 Biosynthesis. J Am Chem Soc 2014; 136:4488-91. [DOI: 10.1021/ja500942y] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Hai-Yan He
- State
Key Laboratory of Bio-organic
and Natural Products Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Man-Cheng Tang
- State
Key Laboratory of Bio-organic
and Natural Products Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Feng Zhang
- State
Key Laboratory of Bio-organic
and Natural Products Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Gong-Li Tang
- State
Key Laboratory of Bio-organic
and Natural Products Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
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19
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Davison J, Dorival J, Rabeharindranto H, Mazon H, Chagot B, Gruez A, Weissman KJ. Insights into the function of trans-acyl transferase polyketide synthases from the SAXS structure of a complete module. Chem Sci 2014. [DOI: 10.1039/c3sc53511h] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Combined analysis by SAXS, NMR and homology modeling reveals the structure of an apo module from a trans-acyltransferase polyketide synthase.
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Affiliation(s)
- Jack Davison
- Molecular and Structural Enzymology Group
- Université de Lorraine
- Vandœuvre-Lès-Nancy, France
| | - Jonathan Dorival
- Molecular and Structural Enzymology Group
- Université de Lorraine
- Vandœuvre-Lès-Nancy, France
| | - Hery Rabeharindranto
- Molecular and Structural Enzymology Group
- Université de Lorraine
- Vandœuvre-Lès-Nancy, France
| | - Hortense Mazon
- Molecular and Structural Enzymology Group
- Université de Lorraine
- Vandœuvre-Lès-Nancy, France
| | - Benjamin Chagot
- Molecular and Structural Enzymology Group
- Université de Lorraine
- Vandœuvre-Lès-Nancy, France
| | - Arnaud Gruez
- Molecular and Structural Enzymology Group
- Université de Lorraine
- Vandœuvre-Lès-Nancy, France
| | - Kira J. Weissman
- Molecular and Structural Enzymology Group
- Université de Lorraine
- Vandœuvre-Lès-Nancy, France
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20
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He HY, Pan HX, Wu LF, Zhang BB, Chai HB, Liu W, Tang GL. Quartromicin Biosynthesis: Two Alternative Polyketide Chains Produced by One Polyketide Synthase Assembly Line. ACTA ACUST UNITED AC 2012; 19:1313-23. [DOI: 10.1016/j.chembiol.2012.07.024] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2012] [Revised: 07/10/2012] [Accepted: 07/30/2012] [Indexed: 11/25/2022]
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21
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Busch B, Ueberschaar N, Sugimoto Y, Hertweck C. Interchenar Retrotransfer of Aureothin Intermediates in an Iterative Polyketide Synthase Module. J Am Chem Soc 2012; 134:12382-5. [DOI: 10.1021/ja304454r] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Benjamin Busch
- Leibniz Institute for
Natural Product Research and
Infection Biology, HKI, Beutenbergstrasse 11a, 07745 Jena, Germany,
and Friedrich Schiller University, Jena,
Germany
| | - Nico Ueberschaar
- Leibniz Institute for
Natural Product Research and
Infection Biology, HKI, Beutenbergstrasse 11a, 07745 Jena, Germany,
and Friedrich Schiller University, Jena,
Germany
| | - Yuki Sugimoto
- Leibniz Institute for
Natural Product Research and
Infection Biology, HKI, Beutenbergstrasse 11a, 07745 Jena, Germany,
and Friedrich Schiller University, Jena,
Germany
| | - Christian Hertweck
- Leibniz Institute for
Natural Product Research and
Infection Biology, HKI, Beutenbergstrasse 11a, 07745 Jena, Germany,
and Friedrich Schiller University, Jena,
Germany
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22
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Nikolouli K, Mossialos D. Bioactive compounds synthesized by non-ribosomal peptide synthetases and type-I polyketide synthases discovered through genome-mining and metagenomics. Biotechnol Lett 2012; 34:1393-403. [PMID: 22481301 DOI: 10.1007/s10529-012-0919-2] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2012] [Accepted: 03/21/2012] [Indexed: 12/16/2022]
Abstract
Non-ribosomal peptide synthetases (NRPS) and type-I polyketide synthases (PKS-I) are multimodular enzymes involved in biosynthesis of oligopeptide and polyketide secondary metabolites produced by microorganisms such as bacteria and fungi. New findings regarding the mechanisms underlying NRPS and PKS-I evolution illustrate how microorganisms expand their metabolic potential. During the last decade rapid development of bioinformatics tools as well as improved sequencing and annotation of microbial genomes led to discovery of novel bioactive compounds synthesized by NRPS and PKS-I through genome-mining. Taking advantage of these technological developments metagenomics is a fast growing research field which directly studies microbial genomes or specific gene groups and their products. Discovery of novel bioactive compounds synthesized by NRPS and PKS-I will certainly be accelerated through metagenomics, allowing the exploitation of so far untapped microbial resources in biotechnology and medicine.
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Affiliation(s)
- Katerina Nikolouli
- Department of Biochemistry and Biotechnology, University of Thessaly, Ploutonos 26 & Eolou, 41221, Larissa, Greece
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23
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Degenkolb T, Karimi Aghcheh R, Dieckmann R, Neuhof T, Baker SE, Druzhinina IS, Kubicek CP, Brückner H, von Döhren H. The Production of Multiple Small Peptaibol Families by Single 14-Module Peptide Synthetases in Trichoderma/Hypocrea. Chem Biodivers 2012; 9:499-535. [DOI: 10.1002/cbdv.201100212] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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24
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Rommel KR, Li C, Kelly WL. Identification of a tetraene-containing product of the indanomycin biosynthetic pathway. Org Lett 2011; 13:2536-9. [PMID: 21491871 DOI: 10.1021/ol200570u] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The indanomycin biosynthetic gene (idm) cluster was recently identified from Streptomyces antibioticus NRRL 8167. The disruption of one of these genes, idmH, and the increased production of a previously unreported metabolite in this mutant is reported. The structure of this compound was elucidated and was shown to possess a linear tetraene. This metabolite is not a logical biosynthetic intermediate of indanomycin but instead is likely an alternate product of the pathway.
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Affiliation(s)
- Kathryn R Rommel
- School of Chemistry and Biochemistry and the Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
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25
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Hong H, Leadlay PF, Staunton J. The changing patterns of covalent active site occupancy during catalysis on a modular polyketide synthase multienzyme revealed by ion-trap mass spectrometry. FEBS J 2009; 276:7057-69. [PMID: 19860832 DOI: 10.1111/j.1742-4658.2009.07418.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
A catalytically competent, homodimeric diketide synthase comprising the first extension module of the erythromycin polyketide synthase was analysed using MS, after limited proteolysis to release functional domains, to determine the pattern of covalent attachment of substrates and intermediates to active sites during catalysis. Using the natural substrates, the acyltransferase and acylcarrier protein of the loading module were found to be heavily loaded with propionyl starter groups, while the ketosynthase was fully propionylated. The acylcarrier protein of the extension module was partly occupied by the product diketide, and the adjacent chain-releasing thioesterase domain was vacant, implying that the rate-limiting step is transfer of the diketide from the acylcarrier protein to the thioesterase domain. The data suggest an attractive model for preventing iterative chain extension by efficient repriming of the ketosynthase domain after condensation. Use of the alternative starter unit valeryl-CoA produced an altered pattern, in which a significant proportion of the extension acylcarrier protein was loaded with methylmalonate, not diketide, consistent with the condensation step having become an additional slow step. Strikingly, when NADPH was omitted, the extension acylcarrier protein contained methylmalonate and none of the expected keto diketide, in contrast to results obtained previously by mixing individual recombinant domains, showing the importance of also studying intact modules. The detailed patterns of loading of the extension acylcarrier protein (of which there are two in the homodimer) also provided the first evidence for simultaneous loading of both acylcarrier proteins and for the coordination of timing between the two active centres for chain extension.
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Affiliation(s)
- Hui Hong
- Department of Chemistry, University of Cambridge, UK.
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26
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27
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28
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McAlpine JB. Advances in the understanding and use of the genomic base of microbial secondary metabolite biosynthesis for the discovery of new natural products. JOURNAL OF NATURAL PRODUCTS 2009; 72:566-572. [PMID: 19199817 DOI: 10.1021/np800742z] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Over the past decade major changes have occurred in the access to genome sequences that encode the enzymes responsible for the biosynthesis of secondary metabolites, knowledge of how those sequences translate into the final structure of the metabolite, and the ability to alter the sequence to obtain predicted products via both homologous and heterologous expression. Novel genera have been discovered leading to new chemotypes, but more surprisingly several instances have been uncovered where the apparently general rules of modular translation have not applied. Several new biosynthetic pathways have been unearthed, and our general knowledge grows rapidly. This review aims to highlight some of the more striking discoveries and advances of the decade.
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Affiliation(s)
- James B McAlpine
- Thallion Pharmaceuticals Inc., 7150 Alexander-Fleming, Montreal H4S 2C8, Canada.
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29
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30
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31
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Chopra T, Gokhale RS. Chapter 12 Polyketide Versatility in the Biosynthesis of Complex Mycobacterial Cell Wall Lipids. Methods Enzymol 2009; 459:259-94. [DOI: 10.1016/s0076-6879(09)04612-6] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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32
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Menche D, Arikan F, Perlova O, Horstmann N, Ahlbrecht W, Wenzel SC, Jansen R, Irschik H, Müller R. Stereochemical Determination and Complex Biosynthetic Assembly of Etnangien, a Highly Potent RNA Polymerase Inhibitor from the Myxobacterium Sorangium cellulosum. J Am Chem Soc 2008; 130:14234-43. [DOI: 10.1021/ja804194c] [Citation(s) in RCA: 103] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Dirk Menche
- University of Heidelberg, Department of Organic Chemistry, INF 270, D-69120 Heidelberg, Germany, Helmholtz Centre for Infection Research (HZI), Medicinal Chemistry, Inhoffenstrasse 7, D-38124 Braunschweig, Germany, Helmholtz Centre for Infection Research (HZI), Microbial Drugs and Saarland University, Pharmaceutical Biotechnology, P.O. Box 151150, D-66041 Saarbrücken, Germany
| | - Fatih Arikan
- University of Heidelberg, Department of Organic Chemistry, INF 270, D-69120 Heidelberg, Germany, Helmholtz Centre for Infection Research (HZI), Medicinal Chemistry, Inhoffenstrasse 7, D-38124 Braunschweig, Germany, Helmholtz Centre for Infection Research (HZI), Microbial Drugs and Saarland University, Pharmaceutical Biotechnology, P.O. Box 151150, D-66041 Saarbrücken, Germany
| | - Olena Perlova
- University of Heidelberg, Department of Organic Chemistry, INF 270, D-69120 Heidelberg, Germany, Helmholtz Centre for Infection Research (HZI), Medicinal Chemistry, Inhoffenstrasse 7, D-38124 Braunschweig, Germany, Helmholtz Centre for Infection Research (HZI), Microbial Drugs and Saarland University, Pharmaceutical Biotechnology, P.O. Box 151150, D-66041 Saarbrücken, Germany
| | - Nicole Horstmann
- University of Heidelberg, Department of Organic Chemistry, INF 270, D-69120 Heidelberg, Germany, Helmholtz Centre for Infection Research (HZI), Medicinal Chemistry, Inhoffenstrasse 7, D-38124 Braunschweig, Germany, Helmholtz Centre for Infection Research (HZI), Microbial Drugs and Saarland University, Pharmaceutical Biotechnology, P.O. Box 151150, D-66041 Saarbrücken, Germany
| | - Wiebke Ahlbrecht
- University of Heidelberg, Department of Organic Chemistry, INF 270, D-69120 Heidelberg, Germany, Helmholtz Centre for Infection Research (HZI), Medicinal Chemistry, Inhoffenstrasse 7, D-38124 Braunschweig, Germany, Helmholtz Centre for Infection Research (HZI), Microbial Drugs and Saarland University, Pharmaceutical Biotechnology, P.O. Box 151150, D-66041 Saarbrücken, Germany
| | - Silke C. Wenzel
- University of Heidelberg, Department of Organic Chemistry, INF 270, D-69120 Heidelberg, Germany, Helmholtz Centre for Infection Research (HZI), Medicinal Chemistry, Inhoffenstrasse 7, D-38124 Braunschweig, Germany, Helmholtz Centre for Infection Research (HZI), Microbial Drugs and Saarland University, Pharmaceutical Biotechnology, P.O. Box 151150, D-66041 Saarbrücken, Germany
| | - Rolf Jansen
- University of Heidelberg, Department of Organic Chemistry, INF 270, D-69120 Heidelberg, Germany, Helmholtz Centre for Infection Research (HZI), Medicinal Chemistry, Inhoffenstrasse 7, D-38124 Braunschweig, Germany, Helmholtz Centre for Infection Research (HZI), Microbial Drugs and Saarland University, Pharmaceutical Biotechnology, P.O. Box 151150, D-66041 Saarbrücken, Germany
| | - Herbert Irschik
- University of Heidelberg, Department of Organic Chemistry, INF 270, D-69120 Heidelberg, Germany, Helmholtz Centre for Infection Research (HZI), Medicinal Chemistry, Inhoffenstrasse 7, D-38124 Braunschweig, Germany, Helmholtz Centre for Infection Research (HZI), Microbial Drugs and Saarland University, Pharmaceutical Biotechnology, P.O. Box 151150, D-66041 Saarbrücken, Germany
| | - Rolf Müller
- University of Heidelberg, Department of Organic Chemistry, INF 270, D-69120 Heidelberg, Germany, Helmholtz Centre for Infection Research (HZI), Medicinal Chemistry, Inhoffenstrasse 7, D-38124 Braunschweig, Germany, Helmholtz Centre for Infection Research (HZI), Microbial Drugs and Saarland University, Pharmaceutical Biotechnology, P.O. Box 151150, D-66041 Saarbrücken, Germany
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Chopra T, Banerjee S, Gupta S, Yadav G, Anand S, Surolia A, Roy RP, Mohanty D, Gokhale RS. Novel intermolecular iterative mechanism for biosynthesis of mycoketide catalyzed by a bimodular polyketide synthase. PLoS Biol 2008; 6:e163. [PMID: 18613748 PMCID: PMC2443190 DOI: 10.1371/journal.pbio.0060163] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2007] [Accepted: 05/27/2008] [Indexed: 11/18/2022] Open
Abstract
In recent years, remarkable versatility of polyketide synthases (PKSs) has been recognized; both in terms of their structural and functional organization as well as their ability to produce compounds other than typical secondary metabolites. Multifunctional Type I PKSs catalyze the biosynthesis of polyketide products by either using the same active sites repetitively (iterative) or by using these catalytic domains only once (modular) during the entire biosynthetic process. The largest open reading frame in Mycobacterium tuberculosis, pks12, was recently proposed to be involved in the biosynthesis of mannosyl-β-1-phosphomycoketide (MPM). The PKS12 protein contains two complete sets of modules and has been suggested to synthesize mycoketide by five alternating condensations of methylmalonyl and malonyl units by using an iterative mode of catalysis. The bimodular iterative catalysis would require transfer of intermediate chains from acyl carrier protein domain of module 2 to ketosynthase domain of module 1. Such bimodular iterations during PKS biosynthesis have not been characterized and appear unlikely based on recent understanding of the three-dimensional organization of these proteins. Moreover, all known examples of iterative PKSs so far characterized involve unimodular iterations. Based on cell-free reconstitution of PKS12 enzymatic machinery, in this study, we provide the first evidence for a novel “modularly iterative” mechanism of biosynthesis. By combination of biochemical, computational, mutagenic, analytical ultracentrifugation and atomic force microscopy studies, we propose that PKS12 protein is organized as a large supramolecular assembly mediated through specific interactions between the C- and N-terminus linkers. PKS12 protein thus forms a modular assembly to perform repetitive condensations analogous to iterative proteins. This novel intermolecular iterative biosynthetic mechanism provides new perspective to our understanding of polyketide biosynthetic machinery and also suggests new ways to engineer polyketide metabolites. The characterization of novel molecular mechanisms involved in biosynthesis of mycobacterial virulent lipids has opened new avenues for drug discovery. Polyketide synthases (PKSs) form a large family of multifunctional proteins involved in the biosynthesis of diverse classes of natural products. Mycobacterium tuberculosis (Mtb) exploits these polyketide biosynthetic enzymes to synthesize complex lipids, many of which are essential for its virulence. PKSs utilize two common mechanistic themes to produce these metabolites: (1) modular—in which each set of catalytic sites is used only once during the entire biosynthetic process and (2) iterative—in which the same set of active sites is used repeatedly. Our study with PKS12 protein from Mtb (the largest protein in this genome) reveals a third mechanism for polyketide biosynthesis. In this hybrid “modularly iterative” mechanism, PKS12 protein forms a supramolecular assembly to perform repetitive cycles of iterations. The protein assembly is formed by specific intermolecular interactions between N- and C-terminus linkers, analogous to modular PKSs. Our study adds a new dimension to the existing catalytic and mechanistic versatility of PKSs, providing a new perspective on how metabolic diversity could be generated by different combinations of existing functional scaffolds. A novel iterative biosynthetic mechanism for multifunctional polyketide synthases reveals how the metabolic diversity of this enzyme family can arise by using existing scaffolds in novel combinations.
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Affiliation(s)
- Tarun Chopra
- National Institute of Immunology, New Delhi, India
| | | | - Sarika Gupta
- National Institute of Immunology, New Delhi, India
| | | | - Swadha Anand
- National Institute of Immunology, New Delhi, India
| | | | | | | | - Rajesh S Gokhale
- National Institute of Immunology, New Delhi, India
- * To whom correspondence should be addressed. E-mail:
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Amoutzias GD, Van de Peer Y, Mossialos D. Evolution and taxonomic distribution of nonribosomal peptide and polyketide synthases. Future Microbiol 2008; 3:361-70. [DOI: 10.2217/17460913.3.3.361] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The majority of nonribosomal peptide synthases and type I polyketide synthases are multimodular megasynthases of oligopeptide and polyketide secondary metabolites, respectively. Owing to their multimodular architecture, they synthesize their metabolites in assembly line logic. The ongoing genomic revolution together with the application of computational tools has provided the opportunity to mine the various genomes for these enzymes and identify those organisms that produce many oligopeptide and polyketide metabolites. In addition, scientists have started to comprehend the molecular mechanisms of megasynthase evolution, by duplication, recombination, point mutation and module skipping. This knowledge and computational analyses have been implemented towards predicting the specificity of these megasynthases and the structure of their end products. It is an exciting field, both for gaining deeper insight into their basic molecular mechanisms and exploiting them biotechnologically.
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Affiliation(s)
- Grigoris D Amoutzias
- Department of Plant Systems Biology, VIB & Department of Molecular Genetics, Ghent University, Technologiepark 927, B-9052 Ghent, Belgium
| | - Yves Van de Peer
- Department of Plant Systems Biology, VIB & Department of Molecular Genetics, Ghent University, Technologiepark 927, B-9052 Ghent, Belgium
| | - Dimitris Mossialos
- Department of Biochemistry & Biotechnology, University of Thessaly, Ploutonos & Aiolou 26, GR-41221 Larissa, Greece
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35
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Weissman KJ, Müller R. Protein–Protein Interactions in Multienzyme Megasynthetases. Chembiochem 2008; 9:826-48. [DOI: 10.1002/cbic.200700751] [Citation(s) in RCA: 111] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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36
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Traitcheva N, Jenke-Kodama H, He J, Dittmann E, Hertweck C. Non-Colinear Polyketide Biosynthesis in the Aureothin and Neoaureothin Pathways: An Evolutionary Perspective. Chembiochem 2007; 8:1841-9. [PMID: 17763486 DOI: 10.1002/cbic.200700309] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Aureothin and neoaureothin (spectinabilin) represent rare nitroaryl-substituted polyketide metabolites from Streptomyces thioluteus and Streptomyces orinoci, respectively, which only differ in the lengths of the polyene backbones. Cloning and sequencing of the 39 kb neoaureothin (nor) biosynthesis gene cluster and its comparison with the aureothin (aur) pathway genes revealed that both polyketide synthase (PKS) assembly lines are remarkably similar. In both cases the module architecture breaks with the principle of colinearity, as individual PKS modules are used in an iterative fashion. Parsimony and neighbour-joining phylogenetic studies provided insights into the evolutionary process that led to the programming of these unusual type I PKS systems and to prediction of which modules act iteratively. The iterative function of the first module in the neoaureothin pathway, NorA, was confirmed by a successful cross-complementation.
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Affiliation(s)
- Nelly Traitcheva
- Department of Biomolecular Chemistry, Leibniz-Institute for Natural Product Research and Infection Biology (HKI), Beutenbergstrasse 11a, 07745 Jena, Germany
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Harvey BM, Mironenko T, Sun Y, Hong H, Deng Z, Leadlay PF, Weissman KJ, Haydock SF. Insights into polyether biosynthesis from analysis of the nigericin biosynthetic gene cluster in Streptomyces sp. DSM4137. ACTA ACUST UNITED AC 2007; 14:703-14. [PMID: 17584617 DOI: 10.1016/j.chembiol.2007.05.011] [Citation(s) in RCA: 98] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2007] [Revised: 04/05/2007] [Accepted: 05/04/2007] [Indexed: 11/18/2022]
Abstract
Nigericin was among the first polyether ionophores to be discovered, but its biosynthesis remains obscure. The biosynthetic gene cluster for nigericin has been serendipitously cloned from Streptomyces sp. DSM4137, and deletion of this gene cluster abolished the production of both nigericin and the closely related metabolite abierixin. Detailed comparison of the nigericin biosynthetic genes with their counterparts in the biosynthetic clusters for other polyketides has prompted a significant revision of the proposed common pathway for polyether biosynthesis. In particular, we present evidence that in nigericin, nanchangmycin, and monensin, an unusual ketosynthase-like protein, KSX, transfers the initially formed linear polyketide chain to a discrete acyl carrier protein, ACPX, for oxidative cyclization. Consistent with this, deletion of either monACPX or monKSX from the monensin gene cluster effectively abolished monensin A biosynthesis.
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Affiliation(s)
- Barbara M Harvey
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1GA, UK
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38
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Abstract
6-Deoxyerythronolide B, the macrocyclic aglycone of the antibiotic erythromycin, is synthesized by a polyketide synthase (PKS) that has emerged as the prototypical modular megasynthase. A variety of molecular biological, protein chemical, and biosynthetic experiments over the past two decades have yielded insights into its mechanistic features. More recently, high-resolution structural images of portions of the 6-deoxyerythronolide B synthase have provided a platform for interpreting this wealth of biochemical data, while at the same time presenting a fundamentally new basis for the design of more detailed investigations into this remarkable enzyme. For example, the critical roles of domain-domain interactions and nonconserved linkers, as well as large interdomain movements in the structure and function of modular PKSs, have been highlighted. In turn, these insights point the way forward for more sophisticated and efficient biosynthetic engineering of complex polyketide natural products.
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Affiliation(s)
- Chaitan Khosla
- Department of Chemical Engineering, Stanford University, Stanford, California 94305, USA.
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Wenzel SC, Meiser P, Binz TM, Mahmud T, Müller R. Nonribosomal peptide biosynthesis: point mutations and module skipping lead to chemical diversity. Angew Chem Int Ed Engl 2007; 45:2296-301. [PMID: 16506259 DOI: 10.1002/anie.200503737] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Silke C Wenzel
- Pharmaceutical Biotechnology, Saarland University, P.O. Box 151150, 66041 Saarbrücken, Germany
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40
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Mercer AC, Burkart MD. The ubiquitous carrier protein--a window to metabolite biosynthesis. Nat Prod Rep 2007; 24:750-73. [PMID: 17653358 DOI: 10.1039/b603921a] [Citation(s) in RCA: 96] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Nature has developed a remarkable strategy to isolate metabolites from the milieu of the cell for chemical modification through the use of carrier proteins. Common to both primary and secondary metabolic pathways, acyl-carrier proteins constitute a conserved protein architecture which mediate the biosynthesis of a variety of metabolic products. Analogies have been made between the carrier protein and solid phase resin for chemical synthesis, as both entities provide a mechanism to separate compounds of interest from complex mixtures for selective chemical modification. However, there is significantly more to the carrier protein than an attachment point. In this review, we aim to systematically characterize the role of carrier proteins in various metabolic pathways and outline their utility in biosynthesis and biotechnology; 185 references are cited.
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Affiliation(s)
- Andrew C Mercer
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093-0358, USA
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41
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Crawford JM, Dancy BCR, Hill EA, Udwary DW, Townsend CA. Identification of a starter unit acyl-carrier protein transacylase domain in an iterative type I polyketide synthase. Proc Natl Acad Sci U S A 2006; 103:16728-33. [PMID: 17071746 PMCID: PMC1636523 DOI: 10.1073/pnas.0604112103] [Citation(s) in RCA: 142] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Polyketides are a class of natural products that exhibit a wide range of functional and structural diversity. They include antibiotics, immunosuppressants, antifungals, antihypercholesterolemics, and cytotoxins. Polyketide synthases (PKSs) use chemistry similar to fatty acid synthases (FASs), although building block variation and differing extents of reduction of the growing polyketide chain underlie their biosynthetic versatility. In contrast to the well studied sequential modular type I PKSs, less is known about how the iterative type I PKSs carry out and control chain initiation, elongation, folding, and cyclization during polyketide processing. Domain structure analysis of a group of related fungal, nonreducing PKSs has revealed well defined N-terminal domains longer than commonly seen for FASs and modular PKSs. Predicted structure of this domain disclosed a region similar to malonyl-CoA:acyl-carrier protein (ACP) transacylases (MATs). MATs play a key role transferring precursor CoA thioesters from solution onto FASs and PKSs for chain elongation. On the basis of site-directed mutagenesis, radiolabeling, and kinetics experiments carried out with individual domains of the norsolorinic acid PKS, we propose that the N-terminal domain is a starter unit:ACP transacylase (SAT domain) that selects a C(6) fatty acid from a dedicated yeast-like FAS and transfers this unit onto the PKS ACP, leading to the production of the aflatoxin precursor, norsolorinic acid. These findings could indicate a much broader role for SAT domains in starter unit selection among nonreducing iterative, fungal PKSs, and they provide a biochemical rationale for the classical acetyl "starter unit effect."
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Affiliation(s)
- Jason M. Crawford
- Department of Chemistry, The Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218
| | - Blair C. R. Dancy
- Department of Chemistry, The Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218
| | - Eric A. Hill
- Department of Chemistry, The Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218
| | - Daniel W. Udwary
- Department of Chemistry, The Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218
| | - Craig A. Townsend
- Department of Chemistry, The Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218
- To whom correspondence should be addressed. E-mail:
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42
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Wenzel SC, Meiser P, Binz TM, Mahmud T, Müller R. Nichtribosomale Peptidbiosynthese: Punktmutationen und Überspringen eines Moduls führen zu chemischer Diversität. Angew Chem Int Ed Engl 2006. [DOI: 10.1002/ange.200503737] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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43
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Wenzel SC, Müller R. Formation of novel secondary metabolites by bacterial multimodular assembly lines: deviations from textbook biosynthetic logic. Curr Opin Chem Biol 2006; 9:447-58. [PMID: 16107321 DOI: 10.1016/j.cbpa.2005.08.001] [Citation(s) in RCA: 118] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2005] [Accepted: 08/03/2005] [Indexed: 11/30/2022]
Abstract
Microorganisms produce an immense variety of natural products with useful biological activities. These compounds are often biosynthesized by multifunctional megasynthetases known as polyketide synthases and nonribosomal peptide synthetases. Recent literature on these natural product assembly lines suggests that they have a much greater mechanistic diversity than originally anticipated.
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Affiliation(s)
- Silke C Wenzel
- Pharmaceutical Biotechnology, Saarland University, PO Box 151150, 66041 Saarbrücken, Germany
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44
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Hill AM. The biosynthesis, molecular genetics and enzymology of the polyketide-derived metabolites. Nat Prod Rep 2005; 23:256-320. [PMID: 16572230 DOI: 10.1039/b301028g] [Citation(s) in RCA: 121] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
This review covers the biosynthesis of aliphatic and aromatic polyketides as well as mixed polyketide/NRPS metabolites, and discusses the molecular genetics and enzymology of the proteins responsible for their formation.
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45
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Bode HB, Müller R. Der Einfluss bakterieller Genomik auf die Naturstoff-Forschung. Angew Chem Int Ed Engl 2005. [DOI: 10.1002/ange.200501080] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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46
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Abstract
"There's life in the old dog yet!" This adage also holds true for natural product research. After the era of natural products was declared to be over, because of the introduction of combinatorial synthesis techniques, natural product research has taken a surprising turn back towards a major field of pharmaceutical research. Current challenges, such as emerging multidrug-resistant bacteria, might be overcome by developments which combine genomic knowledge with applied biology and chemistry to identify, produce, and alter the structure of new lead compounds. Significant biological activity is reported much less frequently for synthetic compounds, a fact reflected in the large proportion of natural products and their derivatives in clinical use. This Review describes the impact of microbial genomics on natural products research, in particularly the search for new lead structures and their optimization. The limitations of this research are also discussed, thus allowing a look into future developments.
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Affiliation(s)
- Helge B Bode
- Institut für Pharmazeutische Biotechnologie, Universität des Saarlandes, Postfach 151150, 66041 Saarbrücken, Germany
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47
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Affiliation(s)
- Leonard Katz
- Kosan Biosciences, Incorporated, 3832 Bay Center Place, Hayward, California 94545, USA.
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48
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Abstract
The modular-type polyketide synthase (PKS) that is involved in aureothin (aur) biosynthesis represents one of the first examples in which a single PKS module (AurA) is used in an iterative fashion. Here we report on the heterologous expression of an engineered AurAB fusion protein that unequivocally proves the iterative nature of AurA. In addition, point mutations reveal that aur PKS module 4 participates in polyketide biosynthesis despite its aberrant acyltransferase domain.
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Affiliation(s)
- Jing He
- Hans-Knöll-Institute for Natural Products Research, Beutenbergstrasse 11a, 07745 Jena, Germany
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49
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Wilkinson B, Kendrew SG, Sheridan RM, Leadlay PF. Biosynthetic engineering of polyketide synthases. Expert Opin Ther Pat 2005. [DOI: 10.1517/13543776.13.10.1579] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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50
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Rahman AS, Hothersall J, Crosby J, Simpson TJ, Thomas CM. Tandemly Duplicated Acyl Carrier Proteins, Which Increase Polyketide Antibiotic Production, Can Apparently Function Either in Parallel or in Series. J Biol Chem 2005; 280:6399-408. [PMID: 15583005 DOI: 10.1074/jbc.m409814200] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Polyketide biosynthesis involves the addition of subunits commonly derived from malonate or methylmalonate to a starter unit such as acetate. Type I polyketide synthases are multifunctional polypeptides that contain one or more modules, each of which normally contains all the enzymatic domains for a single round of extension and modification of the polyketide backbone. Acyl carrier proteins (ACP(s)) hold the extender unit to which the starter or growing chain is added. Normally there is one ACP for each ketosynthase module. However, there are an increasing number of known examples of tandemly repeated ACP domains, whose function is as yet unknown. For the doublet and triplet ACP domains in the biosynthetic pathway for the antibiotic mupirocin from Pseudomonas fluorescens NCIMB10586 we have inactivated ACP domains by inframe deletion and amino acid substitution of the active site serine. By deletion analysis each individual ACP from a cluster can provide a basic but reduced activity for the pathway. In the doublet cluster, substitution analysis indicates that the pathway may follow two parallel routes, one via each of the ACPs, thus increasing overall pathway flow. In the triplet cluster, substitution in ACP5 blocked the pathway. Thus ACP5 appears to be arranged "in series" to ACP6 and ACP7. Thus although both the doublet and triplet clusters increase antibiotic production, the mechanisms by which they do this appear to be different and depend specifically on the biosynthetic stage involved. The function of some ACPs may be determined by their location in the protein rather than absolute enzymic activity.
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Affiliation(s)
- Ayesha S Rahman
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
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