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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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Mabesoone MF, Leopold-Messer S, Minas HA, Chepkirui C, Chawengrum P, Reiter S, Meoded RA, Wolf S, Genz F, Magnus N, Piechulla B, Walker AS, Piel J. Evolution-guided engineering of trans-acyltransferase polyketide synthases. Science 2024; 383:1312-1317. [PMID: 38513027 PMCID: PMC11260071 DOI: 10.1126/science.adj7621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Accepted: 02/13/2024] [Indexed: 03/23/2024]
Abstract
Bacterial multimodular polyketide synthases (PKSs) are giant enzymes that generate a wide range of therapeutically important but synthetically challenging natural products. Diversification of polyketide structures can be achieved by engineering these enzymes. However, notwithstanding successes made with textbook cis-acyltransferase (cis-AT) PKSs, tailoring such large assembly lines remains challenging. Unlike textbook PKSs, trans-AT PKSs feature an extraordinary diversity of PKS modules and commonly evolve to form hybrid PKSs. In this study, we analyzed amino acid coevolution to identify a common module site that yields functional PKSs. We used this site to insert and delete diverse PKS parts and create 22 engineered trans-AT PKSs from various pathways and in two bacterial producers. The high success rates of our engineering approach highlight the broader applicability to generate complex designer polyketides.
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Affiliation(s)
- Mathijs F.J. Mabesoone
- Institute of Microbiology, Eidgenössische Technische Hochschule (ETH) Zürich, Vladimir-Prelog-Weg 4, 8093 Zürich, Switzerland
| | - Stefan Leopold-Messer
- Institute of Microbiology, Eidgenössische Technische Hochschule (ETH) Zürich, Vladimir-Prelog-Weg 4, 8093 Zürich, Switzerland
| | - Hannah A. Minas
- Institute of Microbiology, Eidgenössische Technische Hochschule (ETH) Zürich, Vladimir-Prelog-Weg 4, 8093 Zürich, Switzerland
| | - Clara Chepkirui
- Institute of Microbiology, Eidgenössische Technische Hochschule (ETH) Zürich, Vladimir-Prelog-Weg 4, 8093 Zürich, Switzerland
| | - Pornsuda Chawengrum
- Institute of Microbiology, Eidgenössische Technische Hochschule (ETH) Zürich, Vladimir-Prelog-Weg 4, 8093 Zürich, Switzerland
- Chemical Biology Program, Chulabhorn Graduate Institute, Chulabhorn Royal Academy, Bangkok 10210, Thailand
| | - Silke Reiter
- Institute of Microbiology, Eidgenössische Technische Hochschule (ETH) Zürich, Vladimir-Prelog-Weg 4, 8093 Zürich, Switzerland
| | - Roy A. Meoded
- Institute of Microbiology, Eidgenössische Technische Hochschule (ETH) Zürich, Vladimir-Prelog-Weg 4, 8093 Zürich, Switzerland
| | - Sarah Wolf
- Institute of Microbiology, Eidgenössische Technische Hochschule (ETH) Zürich, Vladimir-Prelog-Weg 4, 8093 Zürich, Switzerland
| | - Ferdinand Genz
- Institute of Microbiology, Eidgenössische Technische Hochschule (ETH) Zürich, Vladimir-Prelog-Weg 4, 8093 Zürich, Switzerland
| | - Nancy Magnus
- Institute for Biological Sciences, University of Rostock, Albert-Einstein-Straße 3, 18059 Rostock, Germany
| | - Birgit Piechulla
- Institute for Biological Sciences, University of Rostock, Albert-Einstein-Straße 3, 18059 Rostock, Germany
| | - Allison S. Walker
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, 240 Longwood Avenue, Boston, Massachusetts 02115, United States
- Department of Chemistry, Vanderbilt University, 1234 Stevenson Center Lane, Nashville, Tennessee 37240, United States
- Department of Biological Sciences, Vanderbilt University, 465 21st Avenue S, Nashville, Tennesee 37232, United States
| | - Jörn Piel
- Institute of Microbiology, Eidgenössische Technische Hochschule (ETH) Zürich, Vladimir-Prelog-Weg 4, 8093 Zürich, Switzerland
- Lead contact
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3
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Zhang J, Bista R, Miyazawa T, Keatinge-Clay AT. Boosting titers of engineered triketide and tetraketide synthases to record levels through T7 promoter tuning. Metab Eng 2023; 78:93-98. [PMID: 37257684 PMCID: PMC11059570 DOI: 10.1016/j.ymben.2023.05.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Revised: 05/24/2023] [Accepted: 05/28/2023] [Indexed: 06/02/2023]
Abstract
Modular polyketide synthases (PKS's) are promising platforms for the rational engineering of designer polyketides and commodity chemicals, yet their low productivities are a barrier to the practical biosynthesis of these compounds. Previously, we engineered triketide lactone synthases such as Pik167 using the recently updated module definition and showed they generate hundreds of milligrams of product per liter of Escherichia coli K207-3 shake flask culture. As the molar ratio between the 2 polypeptides of Pik167 is highly skewed, we sought to attenuate the strength of the T7 promoter controlling the production of the smaller, better-expressing polypeptide and thereby increase production of the first polypeptide under the control of an unoptimized T7 promoter. Through this strategy, a 1.8-fold boost in titer was obtained. After a further 1.5-fold boost obtained by increasing the propionate concentration in the media from 20 to 80 mM, a record titer of 791 mg L-1 (627 mg L-1 isolated) was achieved, a 2.6-fold increase overall. Spurred on by this result, the tetraketide synthase Pik1567 was engineered and the T7 promoter attenuation strategy was applied to its second and third genes. A 5-fold boost, from 20 mg L-1 to 100 mg L-1, in the titer of its tetraketide product was achieved.
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Affiliation(s)
- Jie Zhang
- Department of Molecular Biosciences, The University of Texas at Austin, 100 E. 24th St., Austin, TX, 78712, USA
| | - Ramesh Bista
- Department of Molecular Biosciences, The University of Texas at Austin, 100 E. 24th St., Austin, TX, 78712, USA
| | - Takeshi Miyazawa
- Department of Molecular Biosciences, The University of Texas at Austin, 100 E. 24th St., Austin, TX, 78712, USA
| | - Adrian T Keatinge-Clay
- Department of Molecular Biosciences, The University of Texas at Austin, 100 E. 24th St., Austin, TX, 78712, USA.
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4
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Zhai G, Zhu Y, Sun G, Zhou F, Sun Y, Hong Z, Dong C, Leadlay PF, Hong K, Deng Z, Zhou F, Sun Y. Insights into azalomycin F assembly-line contribute to evolution-guided polyketide synthase engineering and identification of intermodular recognition. Nat Commun 2023; 14:612. [PMID: 36739290 PMCID: PMC9899208 DOI: 10.1038/s41467-023-36213-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Accepted: 01/20/2023] [Indexed: 02/06/2023] Open
Abstract
Modular polyketide synthase (PKS) is an ingenious core machine that catalyzes abundant polyketides in nature. Exploring interactions among modules in PKS is very important for understanding the overall biosynthetic process and for engineering PKS assembly-lines. Here, we show that intermodular recognition between the enoylreductase domain ER1/2 inside module 1/2 and the ketosynthase domain KS3 inside module 3 is required for the cross-module enoylreduction in azalomycin F (AZL) biosynthesis. We also show that KS4 of module 4 acts as a gatekeeper facilitating cross-module enoylreduction. Additionally, evidence is provided that module 3 and module 6 in the AZL PKS are evolutionarily homologous, which makes evolution-oriented PKS engineering possible. These results reveal intermodular recognition, furthering understanding of the mechanism of the PKS assembly-line, thus providing different insights into PKS engineering. This also reveals that gene duplication/conversion and subsequent combinations may be a neofunctionalization process in modular PKS assembly-lines, hence providing a different case for supporting the investigation of modular PKS evolution.
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Affiliation(s)
- Guifa Zhai
- Department of Hematology, Zhongnan Hospital of Wuhan University, School of Pharmaceutical Sciences, Wuhan University, 430071, Wuhan, People's Republic of China.,Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (Ministry of Education), Wuhan University, 430071, Wuhan, People's Republic of China
| | - Yan Zhu
- Department of Hematology, Zhongnan Hospital of Wuhan University, School of Pharmaceutical Sciences, Wuhan University, 430071, Wuhan, People's Republic of China.,Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (Ministry of Education), Wuhan University, 430071, Wuhan, People's Republic of China
| | - Guo Sun
- Department of Hematology, Zhongnan Hospital of Wuhan University, School of Pharmaceutical Sciences, Wuhan University, 430071, Wuhan, People's Republic of China.,Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (Ministry of Education), Wuhan University, 430071, Wuhan, People's Republic of China
| | - Fan Zhou
- Department of Hematology, Zhongnan Hospital of Wuhan University, School of Pharmaceutical Sciences, Wuhan University, 430071, Wuhan, People's Republic of China.,Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (Ministry of Education), Wuhan University, 430071, Wuhan, People's Republic of China
| | - Yangning Sun
- Department of Hematology, Zhongnan Hospital of Wuhan University, School of Pharmaceutical Sciences, Wuhan University, 430071, Wuhan, People's Republic of China.,Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (Ministry of Education), Wuhan University, 430071, Wuhan, People's Republic of China
| | - Zhou Hong
- Department of Hematology, Zhongnan Hospital of Wuhan University, School of Pharmaceutical Sciences, Wuhan University, 430071, Wuhan, People's Republic of China.,Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (Ministry of Education), Wuhan University, 430071, Wuhan, People's Republic of China
| | - Chuan Dong
- Department of Hematology, Zhongnan Hospital of Wuhan University, School of Pharmaceutical Sciences, Wuhan University, 430071, Wuhan, People's Republic of China.,Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (Ministry of Education), Wuhan University, 430071, Wuhan, People's Republic of China
| | - Peter F Leadlay
- Department of Biochemistry, University of Cambridge, Cambridge, CB2 1GA, United Kingdom
| | - Kui Hong
- Department of Hematology, Zhongnan Hospital of Wuhan University, School of Pharmaceutical Sciences, Wuhan University, 430071, Wuhan, People's Republic of China.,Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (Ministry of Education), Wuhan University, 430071, Wuhan, People's Republic of China
| | - Zixin Deng
- Department of Hematology, Zhongnan Hospital of Wuhan University, School of Pharmaceutical Sciences, Wuhan University, 430071, Wuhan, People's Republic of China.,Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (Ministry of Education), Wuhan University, 430071, Wuhan, People's Republic of China
| | - Fuling Zhou
- Department of Hematology, Zhongnan Hospital of Wuhan University, School of Pharmaceutical Sciences, Wuhan University, 430071, Wuhan, People's Republic of China
| | - Yuhui Sun
- Department of Hematology, Zhongnan Hospital of Wuhan University, School of Pharmaceutical Sciences, Wuhan University, 430071, Wuhan, People's Republic of China. .,Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (Ministry of Education), Wuhan University, 430071, Wuhan, People's Republic of China. .,Wuhan Research Center for Infectious Diseases and Cancer, Chinese Academy of Medical Sciences, 430071, Wuhan, People's Republic of China.
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5
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Schröder M, Roß T, Hemmerling F, Hahn F. Studying a Bottleneck of Multimodular Polyketide Synthase Processing: the Polyketide Structure-Dependent Performance of Ketoreductase Domains. ACS Chem Biol 2022; 17:1030-1037. [PMID: 35412301 DOI: 10.1021/acschembio.2c00047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Ketoreductases (KRs) are canonical domains of type I polyketide synthases (PKSs). They stereoselectively reduce ACP-bound β-ketothioester intermediates and are responsible for a large part of the stereocenters in reduced polyketides. Albeit essential for the understanding and engineering of PKS, the specific effects of altering the polyketide part of KR precursors on their performance has rarely been studied. We present investigations on the substrate-dependent performance of six isolated KR domains using a library of structurally diverse surrogates for PKS thioester intermediates. A pronounced correlation between the polyketide structure and the KR performance was observed with activity and stereoselectivity diminishing with growing deviation from the natural KR precursor structure. The extent of this decrease and the profile of arising side products was characteristic for the individual KRs. Our results reinforce the importance of structure-KR performance relationships and suggest extended studies with isolated domains and whole PKS modules.
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Affiliation(s)
- Marius Schröder
- Professur für Organische Chemie (Lebensmittelchemie), Fakultät für Biologie, Chemie und Geowissenschaften, Department of Chemistry, Universität Bayreuth, 95447 Bayreuth, Germany
- Biomolekulares Wirkstoffzentrum, Leibniz Universität Hannover, 30167 Hannover, Germany
| | - Theresa Roß
- Professur für Organische Chemie (Lebensmittelchemie), Fakultät für Biologie, Chemie und Geowissenschaften, Department of Chemistry, Universität Bayreuth, 95447 Bayreuth, Germany
| | - Franziska Hemmerling
- Professur für Organische Chemie (Lebensmittelchemie), Fakultät für Biologie, Chemie und Geowissenschaften, Department of Chemistry, Universität Bayreuth, 95447 Bayreuth, Germany
- Biomolekulares Wirkstoffzentrum, Leibniz Universität Hannover, 30167 Hannover, Germany
| | - Frank Hahn
- Professur für Organische Chemie (Lebensmittelchemie), Fakultät für Biologie, Chemie und Geowissenschaften, Department of Chemistry, Universität Bayreuth, 95447 Bayreuth, Germany
- Biomolekulares Wirkstoffzentrum, Leibniz Universität Hannover, 30167 Hannover, Germany
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6
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Engineering the stambomycin modular polyketide synthase yields 37-membered mini-stambomycins. Nat Commun 2022; 13:515. [PMID: 35082289 PMCID: PMC8792006 DOI: 10.1038/s41467-022-27955-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Accepted: 12/21/2021] [Indexed: 12/14/2022] Open
Abstract
The modular organization of the type I polyketide synthases (PKSs) would seem propitious for rational engineering of desirable analogous. However, despite decades of efforts, such experiments remain largely inefficient. Here, we combine multiple, state-of-the-art approaches to reprogram the stambomycin PKS by deleting seven internal modules. One system produces the target 37-membered mini-stambomycin metabolites − a reduction in chain length of 14 carbons relative to the 51-membered parental compounds − but also substantial quantities of shunt metabolites. Our data also support an unprecedented off-loading mechanism of such stalled intermediates involving the C-terminal thioesterase domain of the PKS. The mini-stambomycin yields are reduced relative to wild type, likely reflecting the poor tolerance of the modules downstream of the modified interfaces to the non-native substrates. Overall, we identify factors contributing to the productivity of engineered whole assembly lines, but our findings also highlight the need for further research to increase production titers. Genetic engineering of the type I polyketide synthases (PKSs) to produce desirable analogous remains largely inefficient. Here, the authors leverage multiple approaches to delete seven internal modules from the stambomycin PKS and generate 37-membered mini-stambomycin macrolactones.
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7
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Miyazawa T, Fitzgerald BJ, Keatinge-Clay AT. Preparative production of an enantiomeric pair by engineered polyketide synthases. Chem Commun (Camb) 2021; 57:8762-8765. [PMID: 34378565 DOI: 10.1039/d1cc03073f] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Using the updated module boundary of polyketide assembly lines, modules from the pikromycin synthase were recombined into engineered synthases that furnish an enantiomeric pair of 2-stereocenter triketide lactones at >99% ee with yields up to 0.39 g per liter of E. coli K207-3 in shake flasks.
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Affiliation(s)
- Takeshi Miyazawa
- Department of Molecular Biosciences, The University of Texas at Austin, 100 E. 24th St., Austin, TX 78712, USA.
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8
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Kudo K, Nishimura T, Kozone I, Hashimoto J, Kagaya N, Suenaga H, Ikeda H, Shin-Ya K. Hemiacetal-less rapamycin derivatives designed and produced by genetic engineering of a type I polyketide synthase. Sci Rep 2021; 11:9944. [PMID: 33976244 PMCID: PMC8113240 DOI: 10.1038/s41598-021-88583-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Accepted: 04/14/2021] [Indexed: 11/09/2022] Open
Abstract
Engineering polyketide synthases is one of the most promising ways of producing a variety of polyketide derivatives. Exploring the undiscovered chemical space of this medicinally important class of middle molecular weight natural products will aid in the development of improved drugs in the future. In previous work, we established methodology designated 'module editing' to precisely manipulate polyketide synthase genes cloned in a bacterial artificial chromosome. Here, in the course of investigating the engineering capacity of the rapamycin PKS, novel rapamycin derivatives 1-4, which lack the hemiacetal moiety, were produced through the heterologous expression of engineered variants of the rapamycin PKS. Three kinds of module deletions in the polyketide synthase RapC were designed, and the genetically engineered vectors were prepared by the in vitro module editing technique. Streptomyces avermitilis SUKA34 transformed with these edited PKSs produced new rapamycin derivatives. The planar structures of 1-4 established based on 1D and 2D NMR, ESI-TOF-MS and UV spectra revealed that 2 and 3 had skeletons well-matched to the designs, but 1 and 4 did not. The observations provide important insights into the mechanisms of the later steps of rapamycin skeletal formation as well as the ketone-forming oxygenase RapJ.
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Affiliation(s)
- Kei Kudo
- National Institute of Advanced Industrial Science and Technology (AIST), 2-4-7 Aomi, Koto-ku, Tokyo, Japan
| | - Takehiro Nishimura
- Technology Research Association for Next Generation Natural Products Chemistry, 2-4-7 Aomi, Koto-ku, Tokyo, Japan
| | - Ikuko Kozone
- Japan Biological Informatics Consortium (JBIC), 2-4-32 Aomi, Koto-ku, Tokyo, Japan
| | - Junko Hashimoto
- Japan Biological Informatics Consortium (JBIC), 2-4-32 Aomi, Koto-ku, Tokyo, Japan
| | - Noritaka Kagaya
- Japan Biological Informatics Consortium (JBIC), 2-4-32 Aomi, Koto-ku, Tokyo, Japan
| | - Hikaru Suenaga
- National Institute of Advanced Industrial Science and Technology (AIST), 2-4-7 Aomi, Koto-ku, Tokyo, Japan
| | - Haruo Ikeda
- Kitasato Institute for Life Sciences, Kitasato University, 1-15-1 Kitasato, Minami-ku, Sagamihara, Kanagawa, Japan
| | - Kazuo Shin-Ya
- National Institute of Advanced Industrial Science and Technology (AIST), 2-4-7 Aomi, Koto-ku, Tokyo, Japan. .,Biotechnology Research Center, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, Japan.
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9
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Drufva EE, Spengler NR, Hix EG, Bailey CB. Site-Directed Mutagenesis of Modular Polyketide Synthase Ketoreductase Domains for Altered Stereochemical Control. Chembiochem 2020; 22:1122-1150. [PMID: 33185924 DOI: 10.1002/cbic.202000613] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 11/12/2020] [Indexed: 12/18/2022]
Abstract
Bacterial modular type I polyketide synthases (PKSs) are complex multidomain assembly line proteins that produce a range of pharmaceutically relevant molecules with a high degree of stereochemical control. Due to their colinear properties, they have been considerable targets for rational biosynthetic pathway engineering. Among the domains harbored within these complex assembly lines, ketoreductase (KR) domains have been extensively studied with the goal of altering their stereoselectivity by site-directed mutagenesis, as they confer much of the stereochemical complexity present in pharmaceutically active reduced polyketide scaffolds. Here we review all efforts to date to perform site-directed mutagenesis on PKS KRs, most of which have been done in the context of excised KR domains on model diffusible substrates such as β-keto N-acetyl cysteamine thioesters. We also discuss the challenges around translating the findings of these studies to alter stereocontrol in the context of a complex multidomain enzymatic assembly line.
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Affiliation(s)
- Erin E Drufva
- Department of Chemistry, University of Tennessee, Knoxville, Knoxville, TN 37996, USA
| | - Nolan R Spengler
- Department of Chemistry, University of Tennessee, Knoxville, Knoxville, TN 37996, USA
| | - Elijah G Hix
- Department of Chemistry, University of Tennessee, Knoxville, Knoxville, TN 37996, USA
| | - Constance B Bailey
- Department of Chemistry, University of Tennessee, Knoxville, Knoxville, TN 37996, USA
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