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Li M, Tao H. Enhancing structural diversity of terpenoids by multisubstrate terpene synthases. Beilstein J Org Chem 2024; 20:959-972. [PMID: 38711588 PMCID: PMC11070974 DOI: 10.3762/bjoc.20.86] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Accepted: 04/09/2024] [Indexed: 05/08/2024] Open
Abstract
Terpenoids are one of the largest class of natural products with diverse structures and activities. This enormous diversity is embedded in enzymes called terpene synthases (TSs), which generate diverse terpene skeletons via sophisticated cyclization cascades. In addition to the many highly selective TSs, there are many promiscuous TSs that accept multiple prenyl substrates, or even noncanonical ones, with 6, 7, 8, 11, and 16 carbon atoms, synthesized via chemical approaches, C-methyltransferases, or engineered lepidopteran mevalonate pathways. The substrate promiscuity of TSs not only expands the structural diversity of terpenes but also highlights their potential for the discovery of novel terpenoids via combinatorial biosynthesis. In this review, we focus on the current knowledge on multisubstrate terpene synthases (MSTSs) and highlight their potential applications.
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Affiliation(s)
- Min Li
- Department of Otolaryngology, Zhongnan Hospital of Wuhan University, School of Pharmaceutical Sciences, Wuhan University, Wuhan, Hubei 430071, China
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, Ministry of Education, Wuhan University, Wuhan, Hubei 430071, China
- TaiKang Center for Life and Medical Sciences, Wuhan University, Wuhan, Hubei 430071, China
| | - Hui Tao
- Department of Otolaryngology, Zhongnan Hospital of Wuhan University, School of Pharmaceutical Sciences, Wuhan University, Wuhan, Hubei 430071, China
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, Ministry of Education, Wuhan University, Wuhan, Hubei 430071, China
- TaiKang Center for Life and Medical Sciences, Wuhan University, Wuhan, Hubei 430071, China
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Ma M, Li M, Wu Z, Liang X, Zheng Q, Li D, Wang G, An T. The microbial biosynthesis of noncanonical terpenoids. Appl Microbiol Biotechnol 2024; 108:226. [PMID: 38381229 PMCID: PMC10881772 DOI: 10.1007/s00253-024-13048-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2023] [Revised: 01/22/2024] [Accepted: 02/01/2024] [Indexed: 02/22/2024]
Abstract
Terpenoids are a class of structurally complex, naturally occurring compounds found predominantly in plant, animal, and microorganism secondary metabolites. Classical terpenoids typically have carbon atoms in multiples of five and follow well-defined carbon skeletons, whereas noncanonical terpenoids deviate from these patterns. These noncanonical terpenoids often result from the methyltransferase-catalyzed methylation modification of substrate units, leading to irregular carbon skeletons. In this comprehensive review, various activities and applications of these noncanonical terpenes have been summarized. Importantly, the review delves into the biosynthetic pathways of noncanonical terpenes, including those with C6, C7, C11, C12, and C16 carbon skeletons, in bacteria and fungi host. It also covers noncanonical triterpenes synthesized from non-squalene substrates and nortriterpenes in Ganoderma lucidum, providing detailed examples to elucidate the intricate biosynthetic processes involved. Finally, the review outlines the potential future applications of noncanonical terpenoids. In conclusion, the insights gathered from this review provide a reference for understanding the biosynthesis of these noncanonical terpenes and pave the way for the discovery of additional unique and novel noncanonical terpenes. KEY POINTS: •The activities and applications of noncanonical terpenoids are introduced. •The noncanonical terpenoids with irregular carbon skeletons are presented. •The microbial biosynthesis of noncanonical terpenoids is summarized.
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Affiliation(s)
- Mengyu Ma
- Featured Laboratory for Biosynthesis and Target Discovery of Active Components of Traditional Chinese Medicine, School of Integrated Traditional Chinese and Western Medicine, Binzhou Medical University, Yantai, 264003, China
| | - Mingkai Li
- Featured Laboratory for Biosynthesis and Target Discovery of Active Components of Traditional Chinese Medicine, School of Integrated Traditional Chinese and Western Medicine, Binzhou Medical University, Yantai, 264003, China
| | - Zhenke Wu
- Featured Laboratory for Biosynthesis and Target Discovery of Active Components of Traditional Chinese Medicine, School of Integrated Traditional Chinese and Western Medicine, Binzhou Medical University, Yantai, 264003, China
| | - Xiqin Liang
- Featured Laboratory for Biosynthesis and Target Discovery of Active Components of Traditional Chinese Medicine, School of Integrated Traditional Chinese and Western Medicine, Binzhou Medical University, Yantai, 264003, China
| | - Qiusheng Zheng
- Featured Laboratory for Biosynthesis and Target Discovery of Active Components of Traditional Chinese Medicine, School of Integrated Traditional Chinese and Western Medicine, Binzhou Medical University, Yantai, 264003, China
| | - Defang Li
- Featured Laboratory for Biosynthesis and Target Discovery of Active Components of Traditional Chinese Medicine, School of Integrated Traditional Chinese and Western Medicine, Binzhou Medical University, Yantai, 264003, China.
| | - Guoli Wang
- Featured Laboratory for Biosynthesis and Target Discovery of Active Components of Traditional Chinese Medicine, School of Integrated Traditional Chinese and Western Medicine, Binzhou Medical University, Yantai, 264003, China.
| | - Tianyue An
- Featured Laboratory for Biosynthesis and Target Discovery of Active Components of Traditional Chinese Medicine, School of Integrated Traditional Chinese and Western Medicine, Binzhou Medical University, Yantai, 264003, China.
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3
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Chen R, Wang M, Keasling JD, Hu T, Yin X. Expanding the structural diversity of terpenes by synthetic biology approaches. Trends Biotechnol 2024:S0167-7799(23)00345-1. [PMID: 38233232 DOI: 10.1016/j.tibtech.2023.12.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Revised: 12/08/2023] [Accepted: 12/11/2023] [Indexed: 01/19/2024]
Abstract
Terpenoids display chemical and structural diversities as well as important biological activities. Despite their extreme variability, the range of these structures is limited by the scope of natural products that canonically derive from interconvertible five-carbon (C5) isoprene units. New approaches have recently been developed to expand their structural diversity. This review systematically explores the combinatorial biosynthesis of noncanonical building blocks via the coexpression of the canonical mevalonate (MVA) pathway and C-methyltransferases (C-MTs), or by using the lepidopteran mevalonate (LMVA) pathway. Unnatural terpenoids can be created from farnesyl diphosphate (FPP) analogs by chemobiological synthesis and terpene cyclopropanation by artificial metalloenzymes (ArMs). Advanced technologies to accelerate terpene biosynthesis are discussed. This review provides a valuable reference for increasing the diversity of valuable terpenoids and their derivatives, as well as for expanding their potential applications.
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Affiliation(s)
- Rong Chen
- Key Laboratory of Elemene Class Anti-Cancer Chinese Medicine of Zhejiang Province, School of Pharmacy, School of Public Health, Hangzhou Normal University, Hangzhou 310000, China; Joint BioEnergy Institute, Emeryville, CA 94608, USA.
| | - Ming Wang
- Key Laboratory of Elemene Class Anti-Cancer Chinese Medicine of Zhejiang Province, School of Pharmacy, School of Public Health, Hangzhou Normal University, Hangzhou 310000, China
| | - Jay D Keasling
- Joint BioEnergy Institute, Emeryville, CA 94608, USA; California Institute for Quantitative Biosciences (QB3), University of California, Berkeley, CA 94720, USA; Department of Chemical and Biomolecular Engineering, University of California, Berkeley, CA 94720, USA; Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA; Department of Bioengineering, University of California, Berkeley, CA 94720, USA; Center for Synthetic Biochemistry, Institute for Synthetic Biology, Shenzhen Institutes of Advanced Technologies, Shenzhen 518055, China; Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Lyngby, Denmark
| | - Tianyuan Hu
- Key Laboratory of Elemene Class Anti-Cancer Chinese Medicine of Zhejiang Province, School of Pharmacy, School of Public Health, Hangzhou Normal University, Hangzhou 310000, China
| | - Xiaopu Yin
- Key Laboratory of Elemene Class Anti-Cancer Chinese Medicine of Zhejiang Province, School of Pharmacy, School of Public Health, Hangzhou Normal University, Hangzhou 310000, China.
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Cheah LC, Liu L, Plan MR, Peng B, Lu Z, Schenk G, Vickers CE, Sainsbury F. Product Profiles of Promiscuous Enzymes Can be Altered by Controlling In Vivo Spatial Organization. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2023; 10:e2303415. [PMID: 37750486 PMCID: PMC10646250 DOI: 10.1002/advs.202303415] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Revised: 07/31/2023] [Indexed: 09/27/2023]
Abstract
Enzyme spatial organization is an evolved mechanism for facilitating multi-step biocatalysis and can play an important role in the regulation of promiscuous enzymes. The latter function suggests that artificial spatial organization can be an untapped avenue for controlling the specificity of bioengineered metabolic pathways. A promiscuous terpene synthase (nerolidol synthase) is co-localized and spatially organized with the preceding enzyme (farnesyl diphosphate synthase) in a heterologous production pathway, via translational protein fusion and/or co-encapsulation in a self-assembling protein cage. Spatial organization enhances nerolidol production by ≈11- to ≈62-fold relative to unorganized enzymes. More interestingly, striking differences in the ratio of end products (nerolidol and linalool) are observed with each spatial organization approach. This demonstrates that artificial spatial organization approaches can be harnessed to modulate the product profiles of promiscuous enzymes in engineered pathways in vivo. This extends the application of spatial organization beyond situations where multiple enzymes compete for a single substrate to cases where there is competition among multiple substrates for a single enzyme.
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Affiliation(s)
- Li Chen Cheah
- Australian Institute for Bioengineering and NanotechnologyThe University of QueenslandSt LuciaQLD4072Australia
- CSIRO Future Science Platform in Synthetic BiologyCommonwealth Scientific and Industrial Research Organisation (CSIRO)Dutton ParkSt LuciaQLD4102Australia
- Present address:
Australian Centre for Disease Preparedness5 Portarlington RdEast GeelongVIC3219Australia
| | - Lian Liu
- Metabolomics Australia (Queensland Node)The University of QueenslandSt LuciaQLD4072Australia
| | - Manuel R. Plan
- Metabolomics Australia (Queensland Node)The University of QueenslandSt LuciaQLD4072Australia
| | - Bingyin Peng
- Australian Institute for Bioengineering and NanotechnologyThe University of QueenslandSt LuciaQLD4072Australia
- CSIRO Future Science Platform in Synthetic BiologyCommonwealth Scientific and Industrial Research Organisation (CSIRO)Dutton ParkSt LuciaQLD4102Australia
- ARC Centre of Excellence in Synthetic BiologyQueensland University of TechnologyBrisbaneQLD4000Australia
- School of Biological and Environmental ScienceQueensland University of TechnologyBrisbaneQLD4000Australia
| | - Zeyu Lu
- Australian Institute for Bioengineering and NanotechnologyThe University of QueenslandSt LuciaQLD4072Australia
- ARC Centre of Excellence in Synthetic BiologyQueensland University of TechnologyBrisbaneQLD4000Australia
| | - Gerhard Schenk
- Australian Institute for Bioengineering and NanotechnologyThe University of QueenslandSt LuciaQLD4072Australia
- School of Chemistry and Molecular BiosciencesThe University of QueenslandSt LuciaQLD4072Australia
| | - Claudia E. Vickers
- Australian Institute for Bioengineering and NanotechnologyThe University of QueenslandSt LuciaQLD4072Australia
- CSIRO Future Science Platform in Synthetic BiologyCommonwealth Scientific and Industrial Research Organisation (CSIRO)Dutton ParkSt LuciaQLD4102Australia
- ARC Centre of Excellence in Synthetic BiologyQueensland University of TechnologyBrisbaneQLD4000Australia
- School of Biological and Environmental ScienceQueensland University of TechnologyBrisbaneQLD4000Australia
- Centre for Cell Factories and BiopolymersGriffith Institute for Drug DiscoveryGriffith UniversityNathanQLD4111Australia
| | - Frank Sainsbury
- Australian Institute for Bioengineering and NanotechnologyThe University of QueenslandSt LuciaQLD4072Australia
- CSIRO Future Science Platform in Synthetic BiologyCommonwealth Scientific and Industrial Research Organisation (CSIRO)Dutton ParkSt LuciaQLD4102Australia
- Centre for Cell Factories and BiopolymersGriffith Institute for Drug DiscoveryGriffith UniversityNathanQLD4111Australia
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Dinday S, Ghosh S. Recent advances in triterpenoid pathway elucidation and engineering. Biotechnol Adv 2023; 68:108214. [PMID: 37478981 DOI: 10.1016/j.biotechadv.2023.108214] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Revised: 07/10/2023] [Accepted: 07/11/2023] [Indexed: 07/23/2023]
Abstract
Triterpenoids are among the most assorted class of specialized metabolites found in all the taxa of living organisms. Triterpenoids are the leading active ingredients sourced from plant species and are utilized in pharmaceutical and cosmetic industries. The triterpenoid precursor 2,3-oxidosqualene, which is biosynthesized via the mevalonate (MVA) pathway is structurally diversified by the oxidosqualene cyclases (OSCs) and other scaffold-decorating enzymes such as cytochrome P450 monooxygenases (P450s), UDP-glycosyltransferases (UGTs) and acyltransferases (ATs). A majority of the bioactive triterpenoids are harvested from the native hosts using the traditional methods of extraction and occasionally semi-synthesized. These methods of supply are time-consuming and do not often align with sustainability goals. Recent advancements in metabolic engineering and synthetic biology have shown prospects for the green routes of triterpenoid pathway reconstruction in heterologous hosts such as Escherichia coli, Saccharomyces cerevisiae and Nicotiana benthamiana, which appear to be quite promising and might lead to the development of alternative source of triterpenoids. The present review describes the biotechnological strategies used to elucidate complex biosynthetic pathways and to understand their regulation and also discusses how the advances in triterpenoid pathway engineering might aid in the scale-up of triterpenoid production in engineered hosts.
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Affiliation(s)
- Sandeep Dinday
- CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow 226015, Uttar Pradesh, India; School of Agricultural Biotechnology, Punjab Agricultural University, Ludhiana 141004, Punjab, India
| | - Sumit Ghosh
- CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow 226015, Uttar Pradesh, India; Academy of Scientific and Innovative Research, Ghaziabad 201002, Uttar Pradesh, India.
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Takekana M, Yoshida T, Yoshida E, Ono S, Horie S, Vavricka CJ, Hiratani M, Tsuge K, Ishii J, Hayakawa Y, Kondo A, Hasunuma T. Online SFE-SFC-MS/MS colony screening: A high-throughput approach for optimizing (-)-limonene production. J Chromatogr B Analyt Technol Biomed Life Sci 2023; 1215:123588. [PMID: 36587464 DOI: 10.1016/j.jchromb.2022.123588] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2022] [Revised: 10/22/2022] [Accepted: 12/24/2022] [Indexed: 12/29/2022]
Abstract
Conventional analysis of microbial bioproducers requires the extraction of metabolites from liquid cultures, where the culturing steps are time consuming and greatly limit throughput. To break through this barrier, the current study aims to directly evaluate microbial bioproduction colonies by way of supercritical fluid extraction-supercritical fluid chromatography-triple quadrupole mass spectrometry (SFE-SFC-MS/MS). The online SFE-SFC-MS/MS system offers great potential for high-throughput analysis due to automated metabolite extraction without any need for pretreatment. This is the first report of SFE-SFC-MS/MS as a method for direct colony screening, as demonstrated in the high-throughput screening of (-)-limonene bioproducers. Compared with conventional analysis, the SFE-SFC-MS/MS system enables faster and more convenient screening of highly productive strains.
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Affiliation(s)
- Musashi Takekana
- Graduate School of Science, Technology and Innovation, Kobe University, Kobe, Japan
| | - Takanobu Yoshida
- Graduate School of Science, Technology and Innovation, Kobe University, Kobe, Japan
| | - Erika Yoshida
- Graduate School of Science, Technology and Innovation, Kobe University, Kobe, Japan; Research Institute for Bioscience Products & Fine Chemicals. Ajinomoto Co., Inc. Kanagawa, Japan
| | - Sumika Ono
- Graduate School of Science, Technology and Innovation, Kobe University, Kobe, Japan
| | | | - Christopher J Vavricka
- Department of Biotechnology and Life Science, Graduate School of Engineering, Tokyo University of Agriculture and Technology, Tokyo, Japan
| | - Moe Hiratani
- Research Institute for Bioscience Products & Fine Chemicals. Ajinomoto Co., Inc. Kanagawa, Japan
| | - Kenji Tsuge
- Graduate School of Science, Technology and Innovation, Kobe University, Kobe, Japan
| | - Jun Ishii
- Graduate School of Science, Technology and Innovation, Kobe University, Kobe, Japan; Engineering Biology Research Center, Kobe University, Kobe, Japan
| | | | - Akihiko Kondo
- Graduate School of Science, Technology and Innovation, Kobe University, Kobe, Japan; Engineering Biology Research Center, Kobe University, Kobe, Japan
| | - Tomohisa Hasunuma
- Graduate School of Science, Technology and Innovation, Kobe University, Kobe, Japan; Engineering Biology Research Center, Kobe University, Kobe, Japan.
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7
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Engineered geranyl diphosphate methyltransferase produces 2-methyl-dimethylallyl diphosphate as a noncanonical C 6 unit for terpenoid biosynthesis. Synth Syst Biotechnol 2022; 8:107-113. [PMID: 36605705 PMCID: PMC9800250 DOI: 10.1016/j.synbio.2022.12.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2022] [Revised: 12/11/2022] [Accepted: 12/12/2022] [Indexed: 12/23/2022] Open
Abstract
Terpenoids constitute the largest class of natural products with complex structures, essential functions, and versatile applications. Creation of new building blocks beyond the conventional five-carbon (C5) units, dimethylallyl diphosphate (DMAPP) and isopentenyl diphosphate, expands significantly the chemical space of terpenoids. Structure-guided engineering of an S-adenosylmethionine-dependent geranyl diphosphate (GPP) C2-methyltransferase from Streptomyces coelicolor yielded variants converting DMAPP to a new C6 unit, 2-methyl-DMAPP. Mutation of the Gly residue at the position 202 resulted in a smaller substrate-binding pocket to fit DMAPP instead of its native substrate GPP. Replacement of Phe residue at the position 222 with a Tyr residue contributed to DMAPP binding via hydrogen bond. Furthermore, using Escherichia coli as the chassis, we demonstrated that 2-methyl-DMAPP was accepted as a start unit to generate noncanonical trans- and cis-prenyl diphosphates (C5n+1) and terpenoids. This work provides insights into substrate recognition of prenyl diphosphate methyltransferases, and strategies to diversify terpenoids by expanding the building block portfolio.
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Expanding the terpene biosynthetic code with non-canonical 16 carbon atom building blocks. Nat Commun 2022; 13:5188. [PMID: 36057727 PMCID: PMC9440906 DOI: 10.1038/s41467-022-32921-w] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Accepted: 08/23/2022] [Indexed: 11/08/2022] Open
Abstract
Humankind relies on specialized metabolites for medicines, flavors, fragrances, and numerous other valuable biomaterials. However, the chemical space occupied by specialized metabolites, and, thus, their application potential, is limited because their biosynthesis is based on only a handful of building blocks. Engineering organisms to synthesize alternative building blocks will bypass this limitation and enable the sustainable production of molecules with non-canonical chemical structures, expanding the possible applications. Herein, we focus on isoprenoids and combine synthetic biology with protein engineering to construct yeast cells that synthesize 10 non-canonical isoprenoid building blocks with 16 carbon atoms. We identify suitable terpene synthases to convert these building blocks into C16 scaffolds and a cytochrome P450 to decorate the terpene scaffolds and produce different oxygenated compounds. Thus, we reconstruct the modular structure of terpene biosynthesis on 16-carbon backbones, synthesizing 28 different non-canonical terpenes, some of which have interesting odorant properties.
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Rinaldi MA, Ferraz CA, Scrutton NS. Alternative metabolic pathways and strategies to high-titre terpenoid production in Escherichia coli. Nat Prod Rep 2022; 39:90-118. [PMID: 34231643 PMCID: PMC8791446 DOI: 10.1039/d1np00025j] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Indexed: 12/14/2022]
Abstract
Covering: up to 2021Terpenoids are a diverse group of chemicals used in a wide range of industries. Microbial terpenoid production has the potential to displace traditional manufacturing of these compounds with renewable processes, but further titre improvements are needed to reach cost competitiveness. This review discusses strategies to increase terpenoid titres in Escherichia coli with a focus on alternative metabolic pathways. Alternative pathways can lead to improved titres by providing higher orthogonality to native metabolism that redirects carbon flux, by avoiding toxic intermediates, by bypassing highly-regulated or bottleneck steps, or by being shorter and thus more efficient and easier to manipulate. The canonical 2-C-methyl-D-erythritol 4-phosphate (MEP) and mevalonate (MVA) pathways are engineered to increase titres, sometimes using homologs from different species to address bottlenecks. Further, alternative terpenoid pathways, including additional entry points into the MEP and MVA pathways, archaeal MVA pathways, and new artificial pathways provide new tools to increase titres. Prenyl diphosphate synthases elongate terpenoid chains, and alternative homologs create orthogonal pathways and increase product diversity. Alternative sources of terpenoid synthases and modifying enzymes can also be better suited for E. coli expression. Mining the growing number of bacterial genomes for new bacterial terpenoid synthases and modifying enzymes identifies enzymes that outperform eukaryotic ones and expand microbial terpenoid production diversity. Terpenoid removal from cells is also crucial in production, and so terpenoid recovery and approaches to handle end-product toxicity increase titres. Combined, these strategies are contributing to current efforts to increase microbial terpenoid production towards commercial feasibility.
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Affiliation(s)
- Mauro A Rinaldi
- Manchester Institute of Biotechnology, Department of Chemistry, School of Natural Sciences, The University of Manchester, 131 Princess Street, Manchester, M1 7DN, UK.
| | - Clara A Ferraz
- Manchester Institute of Biotechnology, Department of Chemistry, School of Natural Sciences, The University of Manchester, 131 Princess Street, Manchester, M1 7DN, UK.
| | - Nigel S Scrutton
- Manchester Institute of Biotechnology, Department of Chemistry, School of Natural Sciences, The University of Manchester, 131 Princess Street, Manchester, M1 7DN, UK.
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Carruthers DN, Lee TS. Diversifying Isoprenoid Platforms via Atypical Carbon Substrates and Non-model Microorganisms. Front Microbiol 2021; 12:791089. [PMID: 34925299 PMCID: PMC8677530 DOI: 10.3389/fmicb.2021.791089] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Accepted: 11/10/2021] [Indexed: 01/07/2023] Open
Abstract
Isoprenoid compounds are biologically ubiquitous, and their characteristic modularity has afforded products ranging from pharmaceuticals to biofuels. Isoprenoid production has been largely successful in Escherichia coli and Saccharomyces cerevisiae with metabolic engineering of the mevalonate (MVA) and methylerythritol phosphate (MEP) pathways coupled with the expression of heterologous terpene synthases. Yet conventional microbial chassis pose several major obstacles to successful commercialization including the affordability of sugar substrates at scale, precursor flux limitations, and intermediate feedback-inhibition. Now, recent studies have challenged typical isoprenoid paradigms by expanding the boundaries of terpene biosynthesis and using non-model organisms including those capable of metabolizing atypical C1 substrates. Conversely, investigations of non-model organisms have historically informed optimization in conventional microbes by tuning heterologous gene expression. Here, we review advances in isoprenoid biosynthesis with specific focus on the synergy between model and non-model organisms that may elevate the commercial viability of isoprenoid platforms by addressing the dichotomy between high titer production and inexpensive substrates.
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Affiliation(s)
- David N Carruthers
- Joint BioEnergy Institute, Emeryville, CA, United States.,Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA, United States
| | - Taek Soon Lee
- Joint BioEnergy Institute, Emeryville, CA, United States.,Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA, United States
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Pang B, Li J, Eiben CB, Oksen E, Barcelos C, Chen R, Englund E, Sundstrom E, Keasling JD. Lepidopteran mevalonate pathway optimization in Escherichia coli efficiently produces isoprenol analogs for next-generation biofuels. Metab Eng 2021; 68:210-219. [PMID: 34673235 DOI: 10.1016/j.ymben.2021.10.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Revised: 10/12/2021] [Accepted: 10/16/2021] [Indexed: 12/31/2022]
Abstract
Terpenes constitute the largest class of natural products with over 55,000 compounds with versatile applications including drugs and biofuels. Introducing structural modifications to terpenes through metabolic engineering is an efficient and sustainable way to improve their properties. Here, we report the optimization of the lepidopteran mevalonate (LMVA) pathway towards the efficient production of isopentenyl pyrophosphate (IPP) analogs as terpene precursors. First, we linked the LMVA pathway to NudB, a promiscuous phosphatase, resulting in the production of the six-carbon analog of 3-methyl-3-buten-1-ol (isoprenol), 3-ethyl-3-buten-1-ol (C6-isoprenol). Using C6-isoprenol as the final product, we then engineered the LMVA pathway by redirecting its upstream portion from a thiolase-dependent pathway to a beta-oxidation pathway. The beta-oxidation LMVA pathway transforms valeric acid, a platform chemical that can be produced from biomass, into C6-isoprenol at a titer of 110.3 mg/L, improved from 5.5 mg/L by the thiolase LMVA pathway, which used propionic acid as a feedstock. Knockout of the E. coli endogenous thiolase genes further improved the C6-isoprenol titer to 390 mg/L, implying efficient production of homo isopentenyl pyrophosphate (HIPP). The beta-oxidation LMVA-NudB pathway also converts butanoic acid and hexanoic acid into isoprenol and isoprenol's seven-carbon analog, 3-propyl-3-buten-1-ol (C7-isoprenol), respectively, suggesting the beta-oxidation LMVA pathway produces IPP and C7-IPP from the corresponding fatty acids. Fuel property tests revealed the longer chain isoprenol analogs have lower water solubilities, similar or higher energy densities, and comparable research octane number (RON) boosting effects to isopentenols. This work not only optimizes the LMVA pathway, setting the basis for homoterpene biosynthesis to expand terpene chemical space, but provides an efficient pathway to produce isoprenol analogs as next-generation biofuels from sustainable feedstocks.
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Affiliation(s)
- Bo Pang
- Joint BioEnergy Institute, Lawrence Berkeley National Laboratory, Emeryville, CA, 94608, United States; Biological Systems and Engineering, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, United States; Department of Chemical & Biomolecular Engineering, University of California, Berkeley, CA, 94720, United States
| | - Jia Li
- Joint BioEnergy Institute, Lawrence Berkeley National Laboratory, Emeryville, CA, 94608, United States; State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, School of Life Sciences, Hubei University, Wuhan, Hubei, 430062, PR China; Biological Systems and Engineering, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, United States
| | - Christopher B Eiben
- Joint BioEnergy Institute, Lawrence Berkeley National Laboratory, Emeryville, CA, 94608, United States; Biological Systems and Engineering, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, United States
| | - Ethan Oksen
- Advanced Biofuels & Bioproducts Process Development Unit, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, United States; Biological Systems and Engineering, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, United States
| | - Carolina Barcelos
- Advanced Biofuels & Bioproducts Process Development Unit, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, United States; Biological Systems and Engineering, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, United States
| | - Rong Chen
- Joint BioEnergy Institute, Lawrence Berkeley National Laboratory, Emeryville, CA, 94608, United States; Biological Systems and Engineering, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, United States; School of Public Health, Hangzhou Normal University, Hangzhou, Zhejiang, 311121, PR China
| | - Elias Englund
- Joint BioEnergy Institute, Lawrence Berkeley National Laboratory, Emeryville, CA, 94608, United States; Biological Systems and Engineering, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, United States
| | - Eric Sundstrom
- Advanced Biofuels & Bioproducts Process Development Unit, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, United States; Biological Systems and Engineering, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, United States
| | - Jay D Keasling
- Joint BioEnergy Institute, Lawrence Berkeley National Laboratory, Emeryville, CA, 94608, United States; Biological Systems and Engineering, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, United States; Department of Chemical & Biomolecular Engineering, University of California, Berkeley, CA, 94720, United States; Novo Nordisk Foundation Center for Biosustainability, Technical University Denmark, DK 2970 Horsholm, Denmark; Center for Synthetic Biochemistry, Shenzhen Institutes for Advanced Technologies, Shenzhen, Guangdong, 518055, PR China.
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12
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Lemfack MC, Brandt W, Krüger K, Gurowietz A, Djifack J, Jung JP, Hopf M, Noack H, Junker B, von Reuß S, Piechulla B. Reaction mechanism of the farnesyl pyrophosphate C-methyltransferase towards the biosynthesis of pre-sodorifen pyrophosphate by Serratia plymuthica 4Rx13. Sci Rep 2021; 11:3182. [PMID: 33542330 PMCID: PMC7862628 DOI: 10.1038/s41598-021-82521-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Accepted: 01/18/2021] [Indexed: 11/25/2022] Open
Abstract
Classical terpenoid biosynthesis involves the cyclization of the linear prenyl pyrophosphate precursors geranyl-, farnesyl-, or geranylgeranyl pyrophosphate (GPP, FPP, GGPP) and their isomers, to produce a huge number of natural compounds. Recently, it was shown for the first time that the biosynthesis of the unique homo-sesquiterpene sodorifen by Serratia plymuthica 4Rx13 involves a methylated and cyclized intermediate as the substrate of the sodorifen synthase. To further support the proposed biosynthetic pathway, we now identified the cyclic prenyl pyrophosphate intermediate pre-sodorifen pyrophosphate (PSPP). Its absolute configuration (6R,7S,9S) was determined by comparison of calculated and experimental CD-spectra of its hydrolysis product and matches with those predicted by semi-empirical quantum calculations of the reaction mechanism. In silico modeling of the reaction mechanism of the FPP C-methyltransferase (FPPMT) revealed a SN2 mechanism for the methyl transfer followed by a cyclization cascade. The cyclization of FPP to PSPP is guided by a catalytic dyad of H191 and Y39 and involves an unprecedented cyclopropyl intermediate. W46, W306, F56, and L239 form the hydrophobic binding pocket and E42 and H45 complex a magnesium cation that interacts with the diphosphate moiety of FPP. Six additional amino acids turned out to be essential for product formation and the importance of these amino acids was subsequently confirmed by site-directed mutagenesis. Our results reveal the reaction mechanism involved in methyltransferase-catalyzed cyclization and demonstrate that this coupling of C-methylation and cyclization of FPP by the FPPMT represents an alternative route of terpene biosynthesis that could increase the terpenoid diversity and structural space.
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Affiliation(s)
- Marie Chantal Lemfack
- Institute of Biological Sciences, University of Rostock, Albert-Einstein-Straße 3, 18059, Rostock, Germany.
| | - Wolfgang Brandt
- Department of Bioorganic Chemistry, Leibniz-Institute of Plant Biochemistry, Weinberg 3, 06120, Halle, Germany.
| | - Katja Krüger
- Institute of Biological Sciences, University of Rostock, Albert-Einstein-Straße 3, 18059, Rostock, Germany.,Department of Internal Medicine I, University Hospital RWTH Aachen, 52074, Aachen, Germany
| | - Alexandra Gurowietz
- Department of Bioorganic Chemistry, Leibniz-Institute of Plant Biochemistry, Weinberg 3, 06120, Halle, Germany.,Institute of Biology, Martin-Luther-Universität Halle-Wittenberg, Weinberg 10, 06120, Halle (Saale), Germany
| | - Jacky Djifack
- Institute of Biological Sciences, University of Rostock, Albert-Einstein-Straße 3, 18059, Rostock, Germany.,PIMAN Consultants, 12 Rue Barthelemy Danjou, 92100, Boulogne-Billancourt, France
| | - Jan-Philip Jung
- Institute of Biological Sciences, University of Rostock, Albert-Einstein-Straße 3, 18059, Rostock, Germany
| | - Marius Hopf
- Institute of Biological Sciences, University of Rostock, Albert-Einstein-Straße 3, 18059, Rostock, Germany.,Duale Hochschule Gera-Eisenach, Weg der Freundschaft 4, 07546, Gera, Germany
| | - Heiko Noack
- Institute of Pharmacy/Biosynthesis of Active Substances, Hoher Weg 8, 06120, Halle (Saale), Germany
| | - Björn Junker
- Institute of Pharmacy/Biosynthesis of Active Substances, Hoher Weg 8, 06120, Halle (Saale), Germany
| | - Stephan von Reuß
- Laboratory of Bioanalytical Chemistry, Institute of Chemistry, University of Neuchatel, Avenue de Bellevaux 51, 2000, Neuchâtel, Switzerland
| | - Birgit Piechulla
- Institute of Biological Sciences, University of Rostock, Albert-Einstein-Straße 3, 18059, Rostock, Germany
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13
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Malico AA, Calzini MA, Gayen AK, Williams GJ. Synthetic biology, combinatorial biosynthesis, and chemo‑enzymatic synthesis of isoprenoids. J Ind Microbiol Biotechnol 2020; 47:675-702. [PMID: 32880770 PMCID: PMC7666032 DOI: 10.1007/s10295-020-02306-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Accepted: 08/27/2020] [Indexed: 12/12/2022]
Abstract
Isoprenoids are a large class of natural products with myriad applications as bioactive and commercial compounds. Their diverse structures are derived from the biosynthetic assembly and tailoring of their scaffolds, ultimately constructed from two C5 hemiterpene building blocks. The modular logic of these platforms can be harnessed to improve titers of valuable isoprenoids in diverse hosts and to produce new-to-nature compounds. Often, this process is facilitated by the substrate or product promiscuity of the component enzymes, which can be leveraged to produce novel isoprenoids. To complement rational enhancements and even re-programming of isoprenoid biosynthesis, high-throughput approaches that rely on searching through large enzymatic libraries are being developed. This review summarizes recent advances and strategies related to isoprenoid synthetic biology, combinatorial biosynthesis, and chemo-enzymatic synthesis, focusing on the past 5 years. Emerging applications of cell-free biosynthesis and high-throughput tools are included that culminate in a discussion of the future outlook and perspective of isoprenoid biosynthetic engineering.
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Affiliation(s)
| | - Miles A Calzini
- Department of Chemistry, NC State University, Raleigh, NC, 27695, USA
| | - Anuran K Gayen
- Department of Chemistry, NC State University, Raleigh, NC, 27695, USA
| | - Gavin J Williams
- Department of Chemistry, NC State University, Raleigh, NC, 27695, USA.
- Comparative Medicine Institute, NC State University, Raleigh, NC, 27695, USA.
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14
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Li C, Zhang R, Wang J, Wilson LM, Yan Y. Protein Engineering for Improving and Diversifying Natural Product Biosynthesis. Trends Biotechnol 2020; 38:729-744. [PMID: 31954530 PMCID: PMC7274900 DOI: 10.1016/j.tibtech.2019.12.008] [Citation(s) in RCA: 84] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Revised: 11/26/2019] [Accepted: 12/06/2019] [Indexed: 01/26/2023]
Abstract
Proteins found in nature have traditionally been the most frequently used biocatalysts to produce numerous natural products ranging from commodity chemicals to pharmaceuticals. Protein engineering has emerged as a powerful biotechnological toolbox in the development of metabolic engineering, particularly for the biosynthesis of natural products. Recently, protein engineering has become a favored method to improve enzymatic activity, increase enzyme stability, and expand product spectra in natural product biosynthesis. This review summarizes recent advances and typical strategies in protein engineering, highlighting the paramount role of protein engineering in improving and diversifying the biosynthesis of natural products. Future prospects and research directions are also discussed.
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Affiliation(s)
- Chenyi Li
- School of Chemical, Materials, and Biomedical Engineering, College of Engineering, The University of Georgia, Athens, GA 30602, USA
| | - Ruihua Zhang
- School of Chemical, Materials, and Biomedical Engineering, College of Engineering, The University of Georgia, Athens, GA 30602, USA
| | - Jian Wang
- School of Chemical, Materials, and Biomedical Engineering, College of Engineering, The University of Georgia, Athens, GA 30602, USA
| | - Lauren Marie Wilson
- School of Chemical, Materials, and Biomedical Engineering, College of Engineering, The University of Georgia, Athens, GA 30602, USA
| | - Yajun Yan
- School of Chemical, Materials, and Biomedical Engineering, College of Engineering, The University of Georgia, Athens, GA 30602, USA.
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15
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Piechulla B, Magnus N, Lemfack MC, von Reuss S. Terpenoid Cyclization by SAM-Dependent C-Methyl Transferase. TRENDS IN CHEMISTRY 2020. [DOI: 10.1016/j.trechm.2020.01.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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16
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Johnson LA, Dunbabin A, Benton JCR, Mart RJ, Allemann RK. Modular Chemoenzymatic Synthesis of Terpenes and their Analogues. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202001744] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Luke A. Johnson
- School of Chemistry Cardiff University Park Place Cardiff CF10 3AT UK
| | - Alice Dunbabin
- School of Chemistry Cardiff University Park Place Cardiff CF10 3AT UK
| | | | - Robert J. Mart
- School of Chemistry Cardiff University Park Place Cardiff CF10 3AT UK
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17
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Johnson LA, Dunbabin A, Benton JCR, Mart RJ, Allemann RK. Modular Chemoenzymatic Synthesis of Terpenes and their Analogues. Angew Chem Int Ed Engl 2020; 59:8486-8490. [DOI: 10.1002/anie.202001744] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Indexed: 01/12/2023]
Affiliation(s)
- Luke A. Johnson
- School of Chemistry Cardiff University Park Place Cardiff CF10 3AT UK
| | - Alice Dunbabin
- School of Chemistry Cardiff University Park Place Cardiff CF10 3AT UK
| | | | - Robert J. Mart
- School of Chemistry Cardiff University Park Place Cardiff CF10 3AT UK
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18
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Eiben CB, Tian T, Thompson MG, Mendez-Perez D, Kaplan N, Goyal G, Chiniquy J, Hillson NJ, Lee TS, Keasling JD. Adenosine Triphosphate and Carbon Efficient Route to Second Generation Biofuel Isopentanol. ACS Synth Biol 2020; 9:468-474. [PMID: 32149502 DOI: 10.1021/acssynbio.9b00402] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Climate change necessitates the development of CO2 neutral or negative routes to chemicals currently produced from fossil carbon. In this paper we demonstrate a pathway from the renewable resource glucose to next generation biofuel isopentanol by pairing the isovaleryl-CoA biosynthesis pathway from Myxococcus xanthus and a butyryl-CoA reductase from Clostridium acetobutylicum. The best plasmid and Escherichia coli strain combination makes 80.50 ± 8.08 (SD) mg/L of isopentanol after 36 h under microaerobic conditions with an oleyl alcohol overlay. In addition, the system also shows a strong preference for isopentanol production over prenol in microaerobic conditions. Finally, the pathway requires zero adenosine triphosphate and can be paired theoretically with nonoxidative glycolysis, the combination being redox balanced from glucose thus avoiding unnecessary carbon loss as CO2. These pathway properties make the isovaleryl-CoA pathway an attractive isopentanol production route for further optimization.
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Affiliation(s)
- Christopher B. Eiben
- Department of Bioengineering, University of California, Berkeley, Berkeley, California 94270, United States
- Department of Bioengineering, University of California, San Francisco, California 94143, United States
| | - Tian Tian
- Joint BioEnergy Institute, Emeryville, California 94608, United States
- Biological Systems & Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Mitchell G. Thompson
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, California 94270, United States
- Joint BioEnergy Institute, Emeryville, California 94608, United States
- Biological Systems & Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Daniel Mendez-Perez
- Joint BioEnergy Institute, Emeryville, California 94608, United States
- Biological Systems & Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Nurgul Kaplan
- Joint BioEnergy Institute, Emeryville, California 94608, United States
- Biological Systems & Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
- Agile BioFoundry, Emeryville, California 94608, United States
| | - Garima Goyal
- Joint BioEnergy Institute, Emeryville, California 94608, United States
- Biological Systems & Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
- Agile BioFoundry, Emeryville, California 94608, United States
| | - Jennifer Chiniquy
- Joint BioEnergy Institute, Emeryville, California 94608, United States
- Biological Systems & Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
- Agile BioFoundry, Emeryville, California 94608, United States
| | - Nathan J. Hillson
- Joint BioEnergy Institute, Emeryville, California 94608, United States
- Biological Systems & Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
- Agile BioFoundry, Emeryville, California 94608, United States
| | - Taek Soon Lee
- Joint BioEnergy Institute, Emeryville, California 94608, United States
- Biological Systems & Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Jay D. Keasling
- Department of Bioengineering, University of California, Berkeley, Berkeley, California 94270, United States
- Department of Chemical & Biomolecular Engineering, University of California, Berkeley, Berkeley, California 94270, United States
- Institute for Quantitative Biosciences, University of California, Berkeley, Berkeley, California 94270, United States
- Joint BioEnergy Institute, Emeryville, California 94608, United States
- Biological Systems & Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
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19
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Building cell factories for the production of advanced fuels. Biochem Soc Trans 2020; 47:1701-1714. [PMID: 31803925 DOI: 10.1042/bst20190168] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Revised: 11/13/2019] [Accepted: 11/15/2019] [Indexed: 12/31/2022]
Abstract
Synthetic biology-based engineering strategies are being extensively employed for microbial production of advanced fuels. Advanced fuels, being comparable in energy efficiency and properties to conventional fuels, have been increasingly explored as they can be directly incorporated into the current fuel infrastructure without the need for reconstructing the pre-existing set-up rendering them economically viable. Multiple metabolic engineering approaches have been used for rewiring microbes to improve existing or develop newly programmed cells capable of efficient fuel production. The primary challenge in using these approaches is improving the product yield for the feasibility of the commercial processes. Some of the common roadblocks towards enhanced fuel production include - limited availability of flux towards precursors and desired pathways due to presence of competing pathways, limited cofactor and energy supply in cells, the low catalytic activity of pathway enzymes, obstructed product transport, and poor tolerance of host cells for end products. Consequently, despite extensive studies on the engineering of microbial hosts, the costs of industrial-scale production of most of these heterologously produced fuel compounds are still too high. Though considerable progress has been made towards successfully producing some of these biofuels, a substantial amount of work needs to be done for improving the titers of others. In this review, we have summarized the different engineering strategies that have been successfully used for engineering pathways into commercial hosts for the production of advanced fuels and different approaches implemented for tuning host strains and pathway enzymes for scaling up production levels.
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20
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The juvenile hormone described in Rhodnius prolixus by Wigglesworth is juvenile hormone III skipped bisepoxide. Sci Rep 2020; 10:3091. [PMID: 32080221 PMCID: PMC7033181 DOI: 10.1038/s41598-020-59495-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Accepted: 01/29/2020] [Indexed: 11/27/2022] Open
Abstract
Juvenile hormones (JHs) are sesquiterpenoids synthesized by the corpora allata (CA). They play critical roles during insect development and reproduction. The first JH was described in 1934 as a “metamorphosis inhibitory hormone” in Rhodnius prolixus by Sir Vincent B. Wigglesworth. Remarkably, in spite of the importance of R. prolixus as vectors of Chagas disease and model organisms in insect physiology, the original JH that Wigglesworth described for the kissing-bug R. prolixus remained unidentified. We employed liquid chromatography mass spectrometry to search for the JH homologs present in the hemolymph of fourth instar nymphs of R. prolixus. Wigglesworth’s original JH is the JH III skipped bisepoxide (JHSB3), a homolog identified in other heteropteran species. Changes in the titer of JHSB3 were studied during the 10-day long molting cycle of 4th instar nymph, between a blood meal and the ecdysis to 5th instar. In addition we measured the changes of mRNA levels in the CA for the 13 enzymes of the JH biosynthetic pathway during the molting cycle of 4th instar. Almost 90 years after the first descriptions of the role of JH in insects, this study finally reveals that the specific JH homolog responsible for Wigglesworth’s original observations is JHSB3.
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