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Liu J, Lin M, Han P, Yao G, Jiang H. Biosynthesis Progress of High-Energy-Density Liquid Fuels Derived from Terpenes. Microorganisms 2024; 12:706. [PMID: 38674649 PMCID: PMC11052473 DOI: 10.3390/microorganisms12040706] [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: 03/07/2024] [Revised: 03/25/2024] [Accepted: 03/26/2024] [Indexed: 04/28/2024] Open
Abstract
High-energy-density liquid fuels (HED fuels) are essential for volume-limited aerospace vehicles and could serve as energetic additives for conventional fuels. Terpene-derived HED biofuel is an important research field for green fuel synthesis. The direct extraction of terpenes from natural plants is environmentally unfriendly and costly. Designing efficient synthetic pathways in microorganisms to achieve high yields of terpenes shows great potential for the application of terpene-derived fuels. This review provides an overview of the current research progress of terpene-derived HED fuels, surveying terpene fuel properties and the current status of biosynthesis. Additionally, we systematically summarize the engineering strategies for biosynthesizing terpenes, including mining and engineering terpene synthases, optimizing metabolic pathways and cell-level optimization, such as the subcellular localization of terpene synthesis and adaptive evolution. This article will be helpful in providing insight into better developing terpene-derived HED fuels.
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Affiliation(s)
- Jiajia Liu
- State Key Laboratory of NBC Protection for Civilian, Beijing 102205, China; (J.L.)
| | - Man Lin
- College of Biological Engineering, Sichuan University of Science and Engineering, Yibin 644005, China
| | - Penggang Han
- State Key Laboratory of NBC Protection for Civilian, Beijing 102205, China; (J.L.)
| | - Ge Yao
- State Key Laboratory of NBC Protection for Civilian, Beijing 102205, China; (J.L.)
| | - Hui Jiang
- State Key Laboratory of NBC Protection for Civilian, Beijing 102205, China; (J.L.)
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2
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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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3
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Whitehead J, Leferink NGH, Johannissen LO, Hay S, Scrutton NS. Decoding Catalysis by Terpene Synthases. ACS Catal 2023; 13:12774-12802. [PMID: 37822860 PMCID: PMC10563020 DOI: 10.1021/acscatal.3c03047] [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: 07/04/2023] [Revised: 08/31/2023] [Indexed: 10/13/2023]
Abstract
The review by Christianson, published in 2017 on the twentieth anniversary of the emergence of the field, summarizes the foundational discoveries and key advances in terpene synthase/cyclase (TS) biocatalysis (Christianson, D. W. Chem Rev2017, 117 (17), 11570-11648. DOI: 10.1021/acs.chemrev.7b00287). Here, we review the TS literature published since then, bringing the field up to date and looking forward to what could be the near future of TS rational design. Many revealing discoveries have been made in recent years, building on the knowledge and fundamental principles uncovered during those initial two decades of study. We use these to explore TS reaction chemistry and see how a combined experimental and computational approach helps to decipher the complexities of TS catalysis. Revealed are a suite of catalytic motifs which control product outcome in TSs, some obvious, some more subtle. We examine each in detail, using the most recent papers and insights to illustrate how exactly this fascinating class of enzymes takes a single acyclic substrate and turns it into the many thousands of complex terpenoids found in Nature. We then explore some of the recent strategies for TS engineering, including machine learning and other data-driven approaches. From this, rational and predictive engineering of TSs, "designer terpene synthases", will begin to emerge as a realistic goal.
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Affiliation(s)
- Joshua
N. Whitehead
- Manchester
Institute of Biotechnology, Department of Chemistry, The University of Manchester, Manchester, M1 7DN, United Kingdom
| | - Nicole G. H. Leferink
- Future
Biomanufacturing Research Hub (FBRH), Manchester Institute of Biotechnology,
Department of Chemistry, The University
of Manchester, Manchester, M1 7DN, United
Kingdom
| | - Linus O. Johannissen
- Manchester
Institute of Biotechnology, Department of Chemistry, The University of Manchester, Manchester, M1 7DN, United Kingdom
| | - Sam Hay
- Manchester
Institute of Biotechnology, Department of Chemistry, The University of Manchester, Manchester, M1 7DN, United Kingdom
| | - Nigel S. Scrutton
- Manchester
Institute of Biotechnology, Department of Chemistry, The University of Manchester, Manchester, M1 7DN, United Kingdom
- Future
Biomanufacturing Research Hub (FBRH), Manchester Institute of Biotechnology,
Department of Chemistry, The University
of Manchester, Manchester, M1 7DN, United
Kingdom
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4
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Lu S, Deng H, Zhou C, Du Z, Guo X, Cheng Y, He X. Enhancement of β-Caryophyllene Biosynthesis in Saccharomyces cerevisiae via Synergistic Evolution of β-Caryophyllene Synthase and Engineering the Chassis. ACS Synth Biol 2023; 12:1696-1707. [PMID: 37224386 DOI: 10.1021/acssynbio.3c00024] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
β-Caryophyllene is a plant-derived bicyclic sesquiterpene with multiple biological functions. β-Caryophyllene production by engineered Saccharomyces cerevisiae represents a promising technological route. However, the low catalytic activity of β-caryophyllene synthase (CPS) is one of the main restrictive factors for β-caryophyllene production. Here, directed evolution of the Artemisia annua CPS was performed, and variants of CPS enhancing the β-caryophyllene biosynthesis in S. cerevisiae were obtained, in which an E353D mutant enzyme presented large improvements in Vmax and Kcat. The Kcat/Km of the E353D mutant was 35.5% higher than that of wild-type CPS. Moreover, the E353D variant exhibited higher catalytic activity in much wider pH and temperature ranges. Thus, both the higher catalytic activity and the robustness of the E353D variant contribute to the 73.3% increase in β-caryophyllene production. Furthermore, the S. cerevisiae chassis was engineered by overexpressing genes related to β-alanine metabolism and MVA pathway to enhance the synthesis of the precursor, and ATP-binding cassette transporter gene variant STE6T1025N to improve the transmembrane transport of β-caryophyllene. The combined engineering of CPS and chassis resulted in 70.45 mg/L of β-caryophyllene after 48 h of cultivation in a test tube, which was 2.93-fold of that of the original strain. Finally, a β-caryophyllene yield of 594.05 mg/L was obtained by fed-batch fermentation, indicating the potential of β-caryophyllene production by yeast.
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Affiliation(s)
- Surui Lu
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing 101408, China
| | - Hong Deng
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing 101408, China
| | - Chenyao Zhou
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing 101408, China
| | - Zhengda Du
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing 101408, China
| | - Xuena Guo
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Yanfei Cheng
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Xiuping He
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing 101408, China
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5
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Chen C, Liu J, Yao G, Bao S, Wan X, Wang F, Wang K, Song T, Han P, Liu T, Jiang H. A novel, genetically encoded whole-cell biosensor for directed evolution of myrcene synthase in Escherichia coli. Biosens Bioelectron 2023; 228:115176. [PMID: 36913884 DOI: 10.1016/j.bios.2023.115176] [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: 01/19/2023] [Revised: 02/15/2023] [Accepted: 02/20/2023] [Indexed: 03/14/2023]
Abstract
β-myrcene is a high-value acyclic monoterpene. The low activity of myrcene synthase resulted to low biosynthetic titer of it. Biosensor is a promising tool applied for enzyme directed evolution. In this work, a novel genetically encoded biosensor responding to myrcene was established based on the MyrR regulator from Pseudomonas sp. Through sensing promoter characterization and engineering, the biosensor exhibiting excellent specificity and dynamic range was developed, and applied for directed evolution of myrcene synthase. After high-throughput screening of the myrcene synthase random mutation library, the best mutant R89G/N152S/D517N was obtained. Its catalytic efficiency was 1.47-fold than that of parent. Based on the mutants, the final production of myrcene reached 510.38 mg/L, which is the highest myrcene titer reported to date. This work demonstrates the great potential of whole-cell biosensor for improving enzymatic activity and the production of target metabolite.
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Affiliation(s)
- Chang Chen
- State Key Laboratory of NBC Protection for Civilian, Beijing, 102205, People's Republic of China
| | - Jiajia Liu
- State Key Laboratory of NBC Protection for Civilian, Beijing, 102205, People's Republic of China
| | - Ge Yao
- State Key Laboratory of NBC Protection for Civilian, Beijing, 102205, People's Republic of China
| | - Shaoheng Bao
- State Key Laboratory of NBC Protection for Civilian, Beijing, 102205, People's Republic of China
| | - Xiukun Wan
- State Key Laboratory of NBC Protection for Civilian, Beijing, 102205, People's Republic of China
| | - Fuli Wang
- State Key Laboratory of NBC Protection for Civilian, Beijing, 102205, People's Republic of China
| | - Kang Wang
- State Key Laboratory of NBC Protection for Civilian, Beijing, 102205, People's Republic of China
| | - Tianyu Song
- State Key Laboratory of NBC Protection for Civilian, Beijing, 102205, People's Republic of China
| | - Penggang Han
- State Key Laboratory of NBC Protection for Civilian, Beijing, 102205, People's Republic of China
| | - Tiangang Liu
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, Ministry of Education and School of Pharmaceutical Sciences, Wuhan University, Wuhan, 430071, People's Republic of China
| | - Hui Jiang
- State Key Laboratory of NBC Protection for Civilian, Beijing, 102205, People's Republic of China.
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6
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Cheah LC, Liu L, Stark T, Plan MR, Peng B, Lu Z, Schenk G, Sainsbury F, Vickers CE. Metabolic flux enhancement from the translational fusion of terpene synthases is linked to terpene synthase accumulation. Metab Eng 2023; 77:143-151. [PMID: 36990382 DOI: 10.1016/j.ymben.2023.03.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Revised: 03/13/2023] [Accepted: 03/26/2023] [Indexed: 03/30/2023]
Abstract
The end-to-end fusion of enzymes that catalyse successive steps in a reaction pathway is a metabolic engineering strategy that has been successfully applied in a variety of pathways and is particularly common in terpene bioproduction. Despite its popularity, limited work has been done to interrogate the mechanism of metabolic enhancement from enzyme fusion. We observed a remarkable >110-fold improvement in nerolidol production upon translational fusion of nerolidol synthase (a sesquiterpene synthase) to farnesyl diphosphate synthase. This delivered a titre increase from 29.6 mg/L up to 4.2 g/L nerolidol in a single engineering step. Whole-cell proteomic analysis revealed that nerolidol synthase levels in the fusion strains were greatly elevated compared to the non-fusion control. Similarly, the fusion of nerolidol synthase to non-catalytic domains also produced comparable increases in titre, which coincided with improved enzyme expression. When farnesyl diphosphate synthase was fused to other terpene synthases, we observed more modest improvements in terpene titre (1.9- and 3.8-fold), corresponding with increases of a similar magnitude in terpene synthase levels. Our data demonstrate that increased in vivo enzyme levels - resulting from improved expression and/or improved protein stability - is a major driver of catalytic enhancement from enzyme fusion.
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Affiliation(s)
- Li Chen Cheah
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St Lucia, QLD, 4072, Australia; CSIRO Future Science Platform in Synthetic Biology, Commonwealth Scientific and Industrial Research Organisation (CSIRO), Dutton Park, QLD, 4102, Australia
| | - Lian Liu
- Metabolomics Australia (Queensland Node), The University of Queensland, QLD, 4072, Australia
| | - Terra Stark
- Metabolomics Australia (Queensland Node), The University of Queensland, QLD, 4072, Australia
| | - Manuel R Plan
- Metabolomics Australia (Queensland Node), The University of Queensland, QLD, 4072, Australia
| | - Bingyin Peng
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St Lucia, QLD, 4072, Australia; CSIRO Future Science Platform in Synthetic Biology, Commonwealth Scientific and Industrial Research Organisation (CSIRO), Dutton Park, QLD, 4102, Australia; ARC Centre of Excellence in Synthetic Biology, Queensland University of Technology, Brisbane, QLD, 4000, Australia
| | - Zeyu Lu
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St Lucia, QLD, 4072, Australia; ARC Centre of Excellence in Synthetic Biology, Queensland University of Technology, Brisbane, QLD, 4000, Australia
| | - Gerhard Schenk
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St Lucia, QLD, 4072, Australia; School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Frank Sainsbury
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St Lucia, QLD, 4072, Australia; CSIRO Future Science Platform in Synthetic Biology, Commonwealth Scientific and Industrial Research Organisation (CSIRO), Dutton Park, QLD, 4102, Australia; Centre for Cell Factories and Biopolymers, Griffith Institute for Drug Discovery, Griffith University, Nathan, QLD, 4111, Australia.
| | - Claudia E Vickers
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St Lucia, QLD, 4072, Australia; CSIRO Future Science Platform in Synthetic Biology, Commonwealth Scientific and Industrial Research Organisation (CSIRO), Dutton Park, QLD, 4102, Australia; ARC Centre of Excellence in Synthetic Biology, Queensland University of Technology, Brisbane, QLD, 4000, Australia; School of Biological and Environmental Science, Queensland University of Technology, Brisbane, QLD, 4000, Australia; Centre for Cell Factories and Biopolymers, Griffith Institute for Drug Discovery, Griffith University, Nathan, QLD, 4111, Australia.
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7
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Lee S, Rim Lee Y, Lee WH, Youn Lee S, Moon M, Woo Park G, Min K, Lee J, Lee JS. Valorization of CO 2 to β-farnesene in Rhodobacter sphaeroides. BIORESOURCE TECHNOLOGY 2022; 363:127955. [PMID: 36115510 DOI: 10.1016/j.biortech.2022.127955] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Revised: 09/06/2022] [Accepted: 09/08/2022] [Indexed: 06/15/2023]
Abstract
The valorization of CO2 into valuable products is a sustainable strategy to help overcome the climate crisis. In particular, biological conversion is attractive as it can produce long-chain hydrocarbons such as terpenoids. This study reports the high yield of β-farnesene production from CO2 by expressing heterologous β-farnesene synthase (FS) into Rhodobacter sphaeroides. To increase the expression of FS, a strong active promoter and a ribosome binding site (RBS) were engineered. Moreover, β-farnesene production was improved further through the supply of exogenous antioxidants and additional nutrients. Finally, β-farnesene was produced from CO2 at a titer of 44.53 mg/L and yield of 234.08 mg/g, values that were correspondingly 23 times and 46 times higher than those from the initial production of β-farnesene. Altogether, the results here suggest that the autotrophic production of β-farnesene can provide a starting point for achieving a circular carbon economy.
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Affiliation(s)
- Sangmin Lee
- Gwangju Bio/Energy Research and Development Center, Korea Institute of Energy Research, Gwangju 61003, Republic of Korea
| | - Yu Rim Lee
- Gwangju Bio/Energy Research and Development Center, Korea Institute of Energy Research, Gwangju 61003, Republic of Korea; Interdisciplinary Program of Agriculture and Life Sciences, Chonnam National University, Gwangju 61186, Republic of Korea
| | - Won-Heong Lee
- Interdisciplinary Program of Agriculture and Life Sciences, Chonnam National University, Gwangju 61186, Republic of Korea; Department of Integrative Food, Bioscience and Biotechnology, Chonnam National University, Gwangju 61186, Republic of Korea
| | - Soo Youn Lee
- Gwangju Bio/Energy Research and Development Center, Korea Institute of Energy Research, Gwangju 61003, Republic of Korea
| | - Myounghoon Moon
- Gwangju Bio/Energy Research and Development Center, Korea Institute of Energy Research, Gwangju 61003, Republic of Korea
| | - Gwon Woo Park
- Gwangju Bio/Energy Research and Development Center, Korea Institute of Energy Research, Gwangju 61003, Republic of Korea
| | - Kyoungseon Min
- Gwangju Bio/Energy Research and Development Center, Korea Institute of Energy Research, Gwangju 61003, Republic of Korea
| | - Juah Lee
- Gwangju Bio/Energy Research and Development Center, Korea Institute of Energy Research, Gwangju 61003, Republic of Korea
| | - Jin-Suk Lee
- Gwangju Bio/Energy Research and Development Center, Korea Institute of Energy Research, Gwangju 61003, Republic of Korea.
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8
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Kwak S, Crook N, Yoneda A, Ahn N, Ning J, Cheng J, Dantas G. Functional mining of novel terpene synthases from metagenomes. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2022; 15:104. [PMID: 36209178 PMCID: PMC9548185 DOI: 10.1186/s13068-022-02189-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Accepted: 07/29/2022] [Indexed: 11/06/2022]
Abstract
BACKGROUND Terpenes are one of the most diverse and abundant classes of natural biomolecules, collectively enabling a variety of therapeutic, energy, and cosmetic applications. Recent genomics investigations have predicted a large untapped reservoir of bacterial terpene synthases residing in the genomes of uncultivated organisms living in the soil, indicating a vast array of putative terpenoids waiting to be discovered. RESULTS We aimed to develop a high-throughput functional metagenomic screening system for identifying novel terpene synthases from bacterial metagenomes by relieving the toxicity of terpene biosynthesis precursors to the Escherichia coli host. The precursor toxicity was achieved using an inducible operon encoding the prenyl pyrophosphate synthetic pathway and supplementation of the mevalonate precursor. Host strain and screening procedures were finely optimized to minimize false positives arising from spontaneous mutations, which avoid the precursor toxicity. Our functional metagenomic screening of human fecal metagenomes yielded a novel β-farnesene synthase, which does not show amino acid sequence similarity to known β-farnesene synthases. Engineered S. cerevisiae expressing the screened β-farnesene synthase produced 120 mg/L β-farnesene from glucose (2.86 mg/g glucose) with a productivity of 0.721 g/L∙h. CONCLUSIONS A unique functional metagenomic screening procedure was established for screening terpene synthases from metagenomic libraries. This research proves the potential of functional metagenomics as a sequence-independent avenue for isolating targeted enzymes from uncultivated organisms in various environmental habitats.
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Affiliation(s)
- Suryang Kwak
- The Edison Family Center for Genome Sciences & Systems Biology, Washington University School of Medicine in St. Louis, 4515 McKinley Avenue, Room 5121, Campus Box 8510, Saint Louis, MO 63110 USA
- Department of Pathology and Immunology, Washington University School of Medicine in St. Louis, Saint Louis, MO 63110 USA
| | - Nathan Crook
- The Edison Family Center for Genome Sciences & Systems Biology, Washington University School of Medicine in St. Louis, 4515 McKinley Avenue, Room 5121, Campus Box 8510, Saint Louis, MO 63110 USA
- Department of Pathology and Immunology, Washington University School of Medicine in St. Louis, Saint Louis, MO 63110 USA
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC 27695 USA
| | - Aki Yoneda
- The Edison Family Center for Genome Sciences & Systems Biology, Washington University School of Medicine in St. Louis, 4515 McKinley Avenue, Room 5121, Campus Box 8510, Saint Louis, MO 63110 USA
- Department of Pathology and Immunology, Washington University School of Medicine in St. Louis, Saint Louis, MO 63110 USA
| | - Naomi Ahn
- The Edison Family Center for Genome Sciences & Systems Biology, Washington University School of Medicine in St. Louis, 4515 McKinley Avenue, Room 5121, Campus Box 8510, Saint Louis, MO 63110 USA
| | - Jie Ning
- The Edison Family Center for Genome Sciences & Systems Biology, Washington University School of Medicine in St. Louis, 4515 McKinley Avenue, Room 5121, Campus Box 8510, Saint Louis, MO 63110 USA
- Department of Pathology and Immunology, Washington University School of Medicine in St. Louis, Saint Louis, MO 63110 USA
| | - Jiye Cheng
- The Edison Family Center for Genome Sciences & Systems Biology, Washington University School of Medicine in St. Louis, 4515 McKinley Avenue, Room 5121, Campus Box 8510, Saint Louis, MO 63110 USA
- Department of Pathology and Immunology, Washington University School of Medicine in St. Louis, Saint Louis, MO 63110 USA
| | - Gautam Dantas
- The Edison Family Center for Genome Sciences & Systems Biology, Washington University School of Medicine in St. Louis, 4515 McKinley Avenue, Room 5121, Campus Box 8510, Saint Louis, MO 63110 USA
- Department of Pathology and Immunology, Washington University School of Medicine in St. Louis, Saint Louis, MO 63110 USA
- Department of Biomedical Engineering, Washington University in St. Louis, Saint Louis, MO 63130 USA
- Department of Molecular Microbiology, Washington University School of Medicine in St. Louis, Saint Louis, MO 63110 USA
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9
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Furubayashi M, Umeno D. Use of directed enzyme evolution to create novel biosynthetic pathways for production of rare or non-natural carotenoids. Methods Enzymol 2022; 671:351-382. [DOI: 10.1016/bs.mie.2022.03.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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10
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Leferink NGH, Scrutton NS. Predictive Engineering of Class I Terpene Synthases Using Experimental and Computational Approaches. Chembiochem 2021; 23:e202100484. [PMID: 34669250 PMCID: PMC9298401 DOI: 10.1002/cbic.202100484] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Revised: 10/15/2021] [Indexed: 12/18/2022]
Abstract
Terpenoids are a highly diverse group of natural products with considerable industrial interest. Increasingly, engineered microbes are used for the production of terpenoids to replace natural extracts and chemical synthesis. Terpene synthases (TSs) show a high level of functional plasticity and are responsible for the vast structural diversity observed in natural terpenoids. Their relatively inert active sites guide intrinsically reactive linear carbocation intermediates along one of many cyclisation paths via exertion of subtle steric and electrostatic control. Due to the absence of a strong protein interaction with these intermediates, there is a remarkable lack of sequence‐function relationship within the TS family, making product‐outcome predictions from sequences alone challenging. This, in combination with the fact that many TSs produce multiple products from a single substrate hampers the design and use of TSs in the biomanufacturing of terpenoids. This review highlights recent advances in genome mining, computational modelling, high‐throughput screening, and machine‐learning that will allow more predictive engineering of these fascinating enzymes in the near future.
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Affiliation(s)
- Nicole G H Leferink
- Future Biomanufacturing Research Hub, 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
- Future Biomanufacturing Research Hub, 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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11
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Liu CL, Xue K, Yang Y, Liu X, Li Y, Lee TS, Bai Z, Tan T. Metabolic engineering strategies for sesquiterpene production in microorganism. Crit Rev Biotechnol 2021; 42:73-92. [PMID: 34256675 DOI: 10.1080/07388551.2021.1924112] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Sesquiterpenes are a large variety of terpene natural products, widely existing in plants, fungi, marine organisms, insects, and microbes. Value-added sesquiterpenes are extensively used in industries such as: food, drugs, fragrances, and fuels. With an increase in market demands and the price of sesquiterpenes, the biosynthesis of sesquiterpenes by microbial fermentation methods from renewable feedstocks is acquiring increasing attention. Synthetic biology provides robust tools of sesquiterpene production in microorganisms. This review presents a summary of metabolic engineering strategies on the hosts and pathway engineering for sesquiterpene production. Advances in synthetic biology provide new strategies on the creation of desired hosts for sesquiterpene production. Especially, metabolic engineering strategies for the production of sesquiterpenes such as: amorphadiene, farnesene, bisabolene, and caryophyllene are emphasized in: Escherichia coli, Saccharomyces cerevisiae, and other microorganisms. Challenges and future perspectives of the bioprocess for translating sesquiterpene production into practical industrial work are also discussed.
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Affiliation(s)
- Chun-Li Liu
- National Engineering Laboratory for Cereal Fermentation Technology, Jiangnan University, Wuxi, China.,College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, PR China.,The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China.,Jiangsu Provincial Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi, China
| | - Kai Xue
- National Engineering Laboratory for Cereal Fermentation Technology, Jiangnan University, Wuxi, China.,The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China.,Jiangsu Provincial Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi, China
| | - Yankun Yang
- National Engineering Laboratory for Cereal Fermentation Technology, Jiangnan University, Wuxi, China.,The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China.,Jiangsu Provincial Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi, China
| | - Xiuxia Liu
- National Engineering Laboratory for Cereal Fermentation Technology, Jiangnan University, Wuxi, China.,The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China.,Jiangsu Provincial Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi, China
| | - Ye Li
- National Engineering Laboratory for Cereal Fermentation Technology, Jiangnan University, Wuxi, China.,The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China.,Jiangsu Provincial Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi, China
| | - Taek Soon Lee
- Joint BioEnergy Institute, Emeryville, CA, USA.,Biological Systems & Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Zhonghu Bai
- National Engineering Laboratory for Cereal Fermentation Technology, Jiangnan University, Wuxi, China.,The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China.,Jiangsu Provincial Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi, China
| | - Tianwei Tan
- College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, PR China
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12
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Furubayashi M, Kubo A, Takemura M, Otani Y, Maoka T, Terada Y, Yaoi K, Ohdan K, Misawa N, Mitani Y. Capsanthin Production in Escherichia coli by Overexpression of Capsanthin/Capsorubin Synthase from Capsicum annuum. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2021; 69:5076-5085. [PMID: 33890772 DOI: 10.1021/acs.jafc.1c00083] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Capsanthin, a characteristic red carotenoid found in the fruits of red pepper (Capsicum annuum), is widely consumed as a food and a functional coloring additive. An enzyme catalyzing capsanthin synthesis was identified as capsanthin/capsorubin synthase (CCS) in the 1990s, but no microbial production of capsanthin has been reported. We report here the first successful attempt to biosynthesize capsanthin in Escherichia coli by carotenoid-pathway engineering. Our initial attempt to coexpress eight enzyme genes required for capsanthin biosynthesis did not detect the desired product. The dual activity of CCS as a lycopene β-cyclase as well as a capsanthin/capsorubin synthase likely complicated the task. We demonstrated that a particularly high expression level of the CCS gene and the minimization of byproducts by regulating the seven upstream carotenogenic genes were crucial for capsanthin formation in E. coli. Our results provide a platform for further study of CCS activity and capsanthin production in microorganisms.
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Affiliation(s)
- Maiko Furubayashi
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Hokkaido 062-8517, Japan
| | - Akiko Kubo
- Institute of Health Sciences, Ezaki Glico Co., Ltd., Osaka 555-8502, Japan
| | - Miho Takemura
- Research Institute for Bioresources and Biotechnology, Ishikawa Prefectural University, Nonoichi, Ishikawa 921-8836, Japan
| | - Yuko Otani
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Hokkaido 062-8517, Japan
| | - Takashi Maoka
- Division of Food Function and Chemistry, Research Institute for Production Development, Kyoto 606-0805, Japan
| | - Yoshinobu Terada
- Institute of Health Sciences, Ezaki Glico Co., Ltd., Osaka 555-8502, Japan
| | - Katsuro Yaoi
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8566, Japan
| | - Kohji Ohdan
- Institute of Health Sciences, Ezaki Glico Co., Ltd., Osaka 555-8502, Japan
| | - Norihiko Misawa
- Research Institute for Bioresources and Biotechnology, Ishikawa Prefectural University, Nonoichi, Ishikawa 921-8836, Japan
| | - Yasuo Mitani
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Hokkaido 062-8517, Japan
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13
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Gonzalez-Esquer CR, Ferlez B, Weraduwage SM, Kirst H, Lantz AT, Turmo A, Sharkey TD, Kerfeld CA. Validation of an insertion-engineered isoprene synthase as a strategy to functionalize terpene synthases. RSC Adv 2021; 11:29997-30005. [PMID: 35480253 PMCID: PMC9041124 DOI: 10.1039/d1ra05710c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Accepted: 08/24/2021] [Indexed: 11/21/2022] Open
Abstract
Terpene synthases are biotechnologically-relevant enzymes with a variety of applications. However, they are typically poor catalysts and have been difficult to engineer. Structurally, most terpene synthases share two conserved domains (α- and β-domains). Some also contain a third domain containing a second active site (γ-domain). Based on the three-domain architecture, we hypothesized that αβ terpene synthases could be engineered by insertion of a heterologous domain at the site of the γ-domain (an approach we term “Insertion-engineering terpene synthase”; Ie-TS). We demonstrate that by mimicking the domain architecture of αβγ terpene synthases, we can redesign isoprene synthase (ISPS), an αβ terpene synthase, while preserving enzymatic activity. Insertion of GFP or a SpyCatcher domain within ISPS introduced new functionality while maintaining or increasing catalytic turnover. This insertion-engineering approach establishes that the γ-domain position is accessible for incorporation of additional sequence features and enables the rational engineering of terpene synthases for biotechnology. “Insertion-engineering” approach allows for the modification of αβ terpene synthases.![]()
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Affiliation(s)
| | - Bryan Ferlez
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI 48824, USA
- Department of Biochemistry & Molecular Biology, Michigan State University, East Lansing, MI 48824, USA
| | - Sarathi M. Weraduwage
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI 48824, USA
- Department of Biochemistry & Molecular Biology, Michigan State University, East Lansing, MI 48824, USA
| | - Henning Kirst
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI 48824, USA
- Environmental Genomics and Systems Biology and Molecular Biophysics and Integrated Bioimaging Divisions, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720, USA
| | - Alexandra T. Lantz
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI 48824, USA
- Department of Biochemistry & Molecular Biology, Michigan State University, East Lansing, MI 48824, USA
| | - Aiko Turmo
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI 48824, USA
- Department of Biochemistry & Molecular Biology, Michigan State University, East Lansing, MI 48824, USA
| | - Thomas D. Sharkey
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI 48824, USA
- Department of Biochemistry & Molecular Biology, Michigan State University, East Lansing, MI 48824, USA
- Plant Resilience Institute, Michigan State University, East Lansing, MI 48824, USA
| | - Cheryl A. Kerfeld
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI 48824, USA
- Department of Biochemistry & Molecular Biology, Michigan State University, East Lansing, MI 48824, USA
- Environmental Genomics and Systems Biology and Molecular Biophysics and Integrated Bioimaging Divisions, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720, USA
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14
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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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15
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Zhu D, Adebisi WA, Ahmad F, Sethupathy S, Danso B, Sun J. Recent Development of Extremophilic Bacteria and Their Application in Biorefinery. Front Bioeng Biotechnol 2020; 8:483. [PMID: 32596215 PMCID: PMC7303364 DOI: 10.3389/fbioe.2020.00483] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Accepted: 04/27/2020] [Indexed: 12/22/2022] Open
Abstract
The biorefining technology for biofuels and chemicals from lignocellulosic biomass has made great progress in the world. However, mobilization of laboratory research toward industrial setup needs to meet a series of criteria, including the selection of appropriate pretreatment technology, breakthrough in enzyme screening, pathway optimization, and production technology, etc. Extremophiles play an important role in biorefinery by providing novel metabolic pathways and catalytically stable/robust enzymes that are able to act as biocatalysts under harsh industrial conditions on their own. This review summarizes the potential application of thermophilic, psychrophilic alkaliphilic, acidophilic, and halophilic bacteria and extremozymes in the pretreatment, saccharification, fermentation, and lignin valorization process. Besides, the latest studies on the engineering bacteria of extremophiles using metabolic engineering and synthetic biology technologies for high-efficiency biofuel production are also introduced. Furthermore, this review explores the comprehensive application potential of extremophiles and extremozymes in biorefinery, which is partly due to their specificity and efficiency, and points out the necessity of accelerating the commercialization of extremozymes.
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Affiliation(s)
- Daochen Zhu
- Biofuels Institute, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, China
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Open Laboratory of Applied Microbiology, Guangdong Institute of Microbiology, Guangzhou, China
| | - Wasiu Adewale Adebisi
- Biofuels Institute, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, China
| | - Fiaz Ahmad
- Biofuels Institute, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, China
| | - Sivasamy Sethupathy
- Biofuels Institute, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, China
| | - Blessing Danso
- Biofuels Institute, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, China
| | - Jianzhong Sun
- Biofuels Institute, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, China
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16
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Protein engineering strategies for microbial production of isoprenoids. Metab Eng Commun 2020; 11:e00129. [PMID: 32612930 PMCID: PMC7322351 DOI: 10.1016/j.mec.2020.e00129] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Revised: 04/06/2020] [Accepted: 04/24/2020] [Indexed: 01/16/2023] Open
Abstract
Isoprenoids comprise one of the most chemically diverse family of natural products with high commercial interest. The structural diversity of isoprenoids is mainly due to the modular activity of three distinct classes of enzymes, including prenyl diphosphate synthases, terpene synthases, and cytochrome P450s. The heterologous expression of these enzymes in microbial systems is suggested to be a promising sustainable way for the production of isoprenoids. Several limitations are associated with native enzymes, such as low stability, activity, and expression profiles. To address these challenges, protein engineering has been applied to improve the catalytic activity, selectivity, and substrate turnover of enzymes. In addition, the natural promiscuity and modular fashion of isoprenoid enzymes render them excellent targets for combinatorial studies and the production of new-to-nature metabolites. In this review, we discuss key individual and multienzyme level strategies for the successful implementation of enzyme engineering towards efficient microbial production of high-value isoprenoids. Challenges and future directions of protein engineering as a complementary strategy to metabolic engineering are likewise outlined. Isoprenoid enzymes are attractive biocatalysts for protein engineering. Isoprenoid enzymes can be engineered for broader substrate promiscuity. Protein engineering can lead to the production of non-natural isoprenoids. Protein engineering can promote co-localization of isoprenoid pathway enzymes. Protein engineering supplements combinatorial biosynthesis for isoprenoid synthesis.
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17
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Li M, Hou F, Wu T, Jiang X, Li F, Liu H, Xian M, Zhang H. Recent advances of metabolic engineering strategies in natural isoprenoid production using cell factories. Nat Prod Rep 2020; 37:80-99. [DOI: 10.1039/c9np00016j] [Citation(s) in RCA: 57] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
This review covers the strategies mostly developed in the last three years for microbial production of isoprenoid, classified according to the engineering targets.
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Affiliation(s)
- Meijie Li
- Key Laboratory of Biobased Materials
- Qingdao Institute of Bioenergy and Bioprocess Technology
- Chinese Academy of Sciences
- Qingdao 266101
- P. R. China
| | - Feifei Hou
- Key Laboratory of Biobased Materials
- Qingdao Institute of Bioenergy and Bioprocess Technology
- Chinese Academy of Sciences
- Qingdao 266101
- P. R. China
| | - Tong Wu
- Key Laboratory of Biobased Materials
- Qingdao Institute of Bioenergy and Bioprocess Technology
- Chinese Academy of Sciences
- Qingdao 266101
- P. R. China
| | - Xinglin Jiang
- The Novo Nordisk Foundation Center for Biosustainability
- Technical University of Denmark
- Lyngby
- Denmark
| | - Fuli Li
- Key Laboratory of Biobased Materials
- Qingdao Institute of Bioenergy and Bioprocess Technology
- Chinese Academy of Sciences
- Qingdao 266101
- P. R. China
| | - Haobao Liu
- Ministry of Agriculture Key Laboratory for Tobacco Biology and Processing
- Tobacco Research Institute
- Chinese Academy of Agricultural Sciences
- Qingdao
- P. R. China
| | - Mo Xian
- Key Laboratory of Biobased Materials
- Qingdao Institute of Bioenergy and Bioprocess Technology
- Chinese Academy of Sciences
- Qingdao 266101
- P. R. China
| | - Haibo Zhang
- Key Laboratory of Biobased Materials
- Qingdao Institute of Bioenergy and Bioprocess Technology
- Chinese Academy of Sciences
- Qingdao 266101
- P. R. China
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18
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Chen Y, Liu L, Shan X, Du G, Zhou J, Chen J. High-Throughput Screening of a 2-Keto-L-Gulonic Acid-Producing Gluconobacter oxydans Strain Based on Related Dehydrogenases. Front Bioeng Biotechnol 2019; 7:385. [PMID: 31921801 PMCID: PMC6923176 DOI: 10.3389/fbioe.2019.00385] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Accepted: 11/18/2019] [Indexed: 01/31/2023] Open
Abstract
High-throughput screening is a powerful tool for discovering strains in the natural environment that may be suitable for target production. Herein, a novel enzyme-based high-throughput screening method was developed for rapid screening of strains overproducing 2-keto-L-gulonic acid (2-KLG). The screening method detects changes in the fluorescence of reduced nicotinamide adenine dinucleotide (NADH) at 340 nm using a microplate reader when 2-KLG is degraded by 2-KLG reductase. In this research, three different 2-KLG reductases were expressed, purified, and studied. The 2-KLG reductase from Aspergillus niger were selected as the best appropriate reductase to establishment the method for its high activity below pH 7. Using the established method, and coupled with fluorescence-activated cell sorting, we achieved a high 2-KLG-producing strain of Gluconobacter oxydans WSH-004 from soil. When cultured with D-sorbitol as the substrate, the 2-KLG yield was 2.5 g/L from 50 g/L D-sorbitol without any side products. Compared with other reported screening methods, our enzyme-based method is more efficient and accurate for obtaining high-producing 2-KLG strains, and it is also convenient and cost-effective. The method is broadly applicable for screening keto acids and other products that can be oxidized via nicotinamide adenine dinucleotide (NAD+) or nicotinamide adenine dinucleotide phosphate (NADP+).
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Affiliation(s)
- Yue Chen
- Key Laboratory of Industrial Biotechnology, Ministry of Education and School of Biotechnology, Jiangnan University, Wuxi, China.,National Engineering Laboratory for Cereal Fermentation Technology, Jiangnan University, Wuxi, China.,Jiangsu Provisional Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi, China
| | - Li Liu
- Key Laboratory of Industrial Biotechnology, Ministry of Education and School of Biotechnology, Jiangnan University, Wuxi, China.,National Engineering Laboratory for Cereal Fermentation Technology, Jiangnan University, Wuxi, China.,Jiangsu Provisional Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi, China
| | - Xiaoyu Shan
- Key Laboratory of Industrial Biotechnology, Ministry of Education and School of Biotechnology, Jiangnan University, Wuxi, China.,National Engineering Laboratory for Cereal Fermentation Technology, Jiangnan University, Wuxi, China.,Jiangsu Provisional Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi, China
| | - Guocheng Du
- Key Laboratory of Industrial Biotechnology, Ministry of Education and School of Biotechnology, Jiangnan University, Wuxi, China.,The Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China
| | - Jingwen Zhou
- Key Laboratory of Industrial Biotechnology, Ministry of Education and School of Biotechnology, Jiangnan University, Wuxi, China.,National Engineering Laboratory for Cereal Fermentation Technology, Jiangnan University, Wuxi, China.,Jiangsu Provisional Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi, China
| | - Jian Chen
- Key Laboratory of Industrial Biotechnology, Ministry of Education and School of Biotechnology, Jiangnan University, Wuxi, China.,National Engineering Laboratory for Cereal Fermentation Technology, Jiangnan University, Wuxi, China
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19
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Xu W, Klumbys E, Ang EL, Zhao H. Emerging molecular biology tools and strategies for engineering natural product biosynthesis. Metab Eng Commun 2019; 10:e00108. [PMID: 32547925 PMCID: PMC7283510 DOI: 10.1016/j.mec.2019.e00108] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Revised: 11/05/2019] [Accepted: 11/05/2019] [Indexed: 02/08/2023] Open
Abstract
Natural products and their related derivatives play a significant role in drug discovery and have been the inspiration for the design of numerous synthetic bioactive compounds. With recent advances in molecular biology, numerous engineering tools and strategies were established to accelerate natural product synthesis in both academic and industrial settings. However, many obstacles in natural product biosynthesis still exist. For example, the native pathways are not appropriate for research or production; the key enzymes do not have enough activity; the native hosts are not suitable for high-level production. Emerging molecular biology tools and strategies have been developed to not only improve natural product titers but also generate novel bioactive compounds. In this review, we will discuss these emerging molecular biology tools and strategies at three main levels: enzyme level, pathway level, and genome level, and highlight their applications in natural product discovery and development.
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Affiliation(s)
- Wei Xu
- Institute of Chemical and Engineering Sciences, Agency for Science, Technology, and Research, Singapore
| | - Evaldas Klumbys
- Institute of Chemical and Engineering Sciences, Agency for Science, Technology, and Research, Singapore
| | - Ee Lui Ang
- Institute of Chemical and Engineering Sciences, Agency for Science, Technology, and Research, Singapore
| | - Huimin Zhao
- Institute of Chemical and Engineering Sciences, Agency for Science, Technology, and Research, Singapore.,Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
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20
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An automated pipeline for the screening of diverse monoterpene synthase libraries. Sci Rep 2019; 9:11936. [PMID: 31417136 PMCID: PMC6695433 DOI: 10.1038/s41598-019-48452-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2019] [Accepted: 07/25/2019] [Indexed: 12/27/2022] Open
Abstract
Monoterpenoids are a structurally diverse group of natural products with applications as pharmaceuticals, flavourings, fragrances, pesticides, and biofuels. Recent advances in synthetic biology offer new routes to this chemical diversity through the introduction of heterologous isoprenoid production pathways into engineered microorganisms. Due to the nature of the branched reaction mechanism, monoterpene synthases often produce multiple products when expressed in monoterpenoid production platforms. Rational engineering of terpene synthases is challenging due to a lack of correlation between protein sequence and cyclisation reaction catalysed. Directed evolution offers an attractive alternative protein engineering strategy as limited prior sequence-function knowledge is required. However, directed evolution of terpene synthases is hampered by the lack of a convenient high-throughput screening assay for the detection of multiple volatile terpene products. Here we applied an automated pipeline for the screening of diverse monoterpene synthase libraries, employing robotic liquid handling platforms coupled to GC-MS, and automated data extraction. We used the pipeline to screen pinene synthase variant libraries, with mutations in three areas of plasticity, capable of producing multiple monoterpene products. We successfully identified variants with altered product profiles and demonstrated good agreement between the results of the automated screen and traditional shake-flask cultures. In addition, useful insights into the cyclisation reaction catalysed by pinene synthase were obtained, including the identification of positions with the highest level of plasticity, and the significance of region 2 in carbocation cyclisation. The results obtained will aid the prediction and design of novel terpene synthase activities towards clean monoterpenoid products.
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21
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The isoprenoid alcohol pathway, a synthetic route for isoprenoid biosynthesis. Proc Natl Acad Sci U S A 2019; 116:12810-12815. [PMID: 31186357 DOI: 10.1073/pnas.1821004116] [Citation(s) in RCA: 87] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The more than 50,000 isoprenoids found in nature are all derived from the 5-carbon diphosphates isopentenyl pyrophosphate (IPP) and dimethylallyl pyrophosphate (DMAPP). Natively, IPP and DMAPP are generated by the mevalonate (MVA) and 2-C-methyl-d-erythritol-4-phosphate (MEP) pathways, which have been engineered to produce compounds with numerous applications. However, as these pathways are inherently constrained by carbon, energy inefficiencies, and their roles in native metabolism, engineering for isoprenoid biosynthesis at high flux, titer, and yield remains a challenge. To overcome these limitations, here we develop an alternative synthetic pathway termed the isoprenoid alcohol (IPA) pathway that centers around the synthesis and subsequent phosphorylation of IPAs. We first established a lower IPA pathway for the conversion of IPAs to isoprenoid pyrophosphate intermediates that enabled the production of greater than 2 g/L geraniol from prenol as well as limonene, farnesol, diaponeurosporene, and lycopene. We then designed upper IPA pathways for the generation of (iso)prenol from central carbon metabolites with the development of a route to prenol enabling its synthesis at more than 2 g/L. Using prenol as the linking intermediate further facilitated an integrated IPA pathway that resulted in the production of nearly 0.6 g/L total monoterpenoids from glycerol as the sole carbon source. The IPA pathway provides an alternative route to isoprenoids that is more energy efficient than native pathways and can serve as a platform for targeting a repertoire of isoprenoid compounds with application as high-value pharmaceuticals, commodity chemicals, and fuels.
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22
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Otani Y, Maoka T, Kawai-Noma S, Saito K, Umeno D. Construction of a pathway to C50-ε-carotene. PLoS One 2019; 14:e0216729. [PMID: 31086389 PMCID: PMC6516660 DOI: 10.1371/journal.pone.0216729] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Accepted: 04/28/2019] [Indexed: 11/18/2022] Open
Abstract
Substrate tolerance of bacterial cyclases has been demonstrated in various contexts, but little is known about that of plant cyclases. Here, we tested two plant ε-cyclases to convert C50-lycopene, which we previously established by rounds of directed evolution. Unlike bacterial β-cyclases, two-end cyclase from lettuce exhibited complete specificity against this molecule, indicating that this enzyme has some mechanism that exerts size-specificity. Arabidopsis one-end cyclase At-y2 showed detectable activity to C50-lycopene. Interestingly, we found that it functions as a two-end cyclase in a C50 context. Based on this observation, a possible model for substrate discrimination of this enzyme is proposed.
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Affiliation(s)
- Yusuke Otani
- Department of Applied Chemistry and Biotechnology, Chiba University, Chiba, Japan
| | - Takashi Maoka
- Research Institute for Production Development, Kyoto, Japan
| | - Shigeko Kawai-Noma
- Department of Applied Chemistry and Biotechnology, Chiba University, Chiba, Japan
| | - Kyoichi Saito
- Department of Applied Chemistry and Biotechnology, Chiba University, Chiba, Japan
| | - Daisuke Umeno
- Department of Applied Chemistry and Biotechnology, Chiba University, Chiba, Japan
- * E-mail:
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23
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Advances in the Metabolic Engineering of Escherichia coli for the Manufacture of Monoterpenes. Catalysts 2019. [DOI: 10.3390/catal9050433] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Monoterpenes are commonly applied as pharmaceuticals and valuable chemicals in various areas. The bioproduction of valuable monoterpenes in prokaryotic microbial hosts, such as E. coli, has progressed considerably thanks to the development of different outstanding approaches. However, the large-scale production of monoterpenes still presents considerable limitations. Thus, process development warrants further investigations. This review discusses the endogenous methylerythritol-4-phosphate-dependent pathway engineering and the exogenous mevalonate-dependent isoprenoid pathway introduction, as well as the accompanied optimization of rate-limiting enzymes, metabolic flux, and product toxicity tolerance. We suggest further studies to focus on the development of systematical, integrational, and synthetic biological strategies in light of the inter disciplines at the cutting edge. Our review provides insights into the current advances of monoterpene bioengineering and serves as a reference for future studies to promote the industrial production of valuable monoterpenes.
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24
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Li L, Furubayashi M, Wang S, Maoka T, Kawai-Noma S, Saito K, Umeno D. Genetically engineered biosynthetic pathways for nonnatural C 60 carotenoids using C 5-elongases and C 50-cyclases in Escherichia coli. Sci Rep 2019; 9:2982. [PMID: 30814614 PMCID: PMC6393565 DOI: 10.1038/s41598-019-39289-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Accepted: 01/22/2019] [Indexed: 11/09/2022] Open
Abstract
While the majority of the natural carotenoid pigments are based on 40-carbon (C40) skeleton, some carotenoids from bacteria have larger C50 skeleton, biosynthesized by attaching two isoprene units (C5) to both sides of the C40 carotenoid pigment lycopene. Subsequent cyclization reactions result in the production of C50 carotenoids with diverse and unique skeletal structures. To produce even larger nonnatural novel carotenoids with C50 + C5 + C5 = C60 skeletons, we systematically coexpressed natural C50 carotenoid biosynthetic enzymes (lycopene C5-elongases and C50-cyclases) from various bacterial sources together with the laboratory-engineered nonnatural C50-lycopene pathway in Escherichia coli. Among the tested enzymes, the elongases and cyclases from Micrococcus luteus exhibited significant activity toward C50-lycopene, and yielded the novel carotenoids C60-flavuxanthin and C60-sarcinaxanthin. Moreover, coexpression of M. luteus elongase with Corynebacterium cyclase resulted in the production of C60-sarcinaxanthin, C60-sarprenoxanthin, and C60-decaprenoxanthin.
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Affiliation(s)
- Ling Li
- Department of Applied Chemistry and Biotechnology, Chiba University, Chiba, Japan
| | - Maiko Furubayashi
- Department of Applied Chemistry and Biotechnology, Chiba University, Chiba, Japan
| | - Shifei Wang
- Department of Applied Chemistry and Biotechnology, Chiba University, Chiba, Japan
| | - Takashi Maoka
- Research Institute for Production Development, Kyoto, Japan
| | - Shigeko Kawai-Noma
- Department of Applied Chemistry and Biotechnology, Chiba University, Chiba, Japan
| | - Kyoichi Saito
- Department of Applied Chemistry and Biotechnology, Chiba University, Chiba, Japan
| | - Daisuke Umeno
- Department of Applied Chemistry and Biotechnology, Chiba University, Chiba, Japan.
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25
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Asker D. High throughput screening and profiling of high-value carotenoids from a wide diversity of bacteria in surface seawater. Food Chem 2018; 261:103-111. [DOI: 10.1016/j.foodchem.2018.03.109] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Revised: 03/14/2018] [Accepted: 03/24/2018] [Indexed: 12/14/2022]
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26
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Tashiro M, Ono K, Kimura Y, Kawai-Noma S, Saito K, Umeno D. Tweezing the cofactor preference of gymnosperm pinene synthase. Biosci Biotechnol Biochem 2018; 82:1058-1061. [PMID: 29793401 DOI: 10.1080/09168451.2018.1459465] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
The cellular activities of gymnosperms monoterpene synthases are largely compromised due to their requirement for manganese, which is deficient in microbial cells. Through site-saturation mutagenesis of the residue adjacent to metal-binding glutamate, we found that pinene synthase is highly mutable at this position yet drastically alter their metal binding preference, thereby quickly improving the cellular performance in heterologous hosts.
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Affiliation(s)
- Miki Tashiro
- a Faculty of Engineering, Department of Applied Chemistry and Biotechnology , Chiba University Nishi-Chiba Campus (Administration Bureau) , Chiba-shi , Japan
| | - Koyo Ono
- a Faculty of Engineering, Department of Applied Chemistry and Biotechnology , Chiba University Nishi-Chiba Campus (Administration Bureau) , Chiba-shi , Japan
| | - Yuki Kimura
- a Faculty of Engineering, Department of Applied Chemistry and Biotechnology , Chiba University Nishi-Chiba Campus (Administration Bureau) , Chiba-shi , Japan
| | - Shigeko Kawai-Noma
- a Faculty of Engineering, Department of Applied Chemistry and Biotechnology , Chiba University Nishi-Chiba Campus (Administration Bureau) , Chiba-shi , Japan
| | - Kyoichi Saito
- a Faculty of Engineering, Department of Applied Chemistry and Biotechnology , Chiba University Nishi-Chiba Campus (Administration Bureau) , Chiba-shi , Japan
| | - Daisuke Umeno
- a Faculty of Engineering, Department of Applied Chemistry and Biotechnology , Chiba University Nishi-Chiba Campus (Administration Bureau) , Chiba-shi , Japan
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27
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Kasey CM, Zerrad M, Li Y, Cropp TA, Williams GJ. Development of Transcription Factor-Based Designer Macrolide Biosensors for Metabolic Engineering and Synthetic Biology. ACS Synth Biol 2018; 7:227-239. [PMID: 28950701 DOI: 10.1021/acssynbio.7b00287] [Citation(s) in RCA: 61] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Macrolides are a large group of natural products that display broad and potent biological activities and are biosynthesized by type I polyketide synthases (PKSs) and associated enzymatic machinery. There is an urgent need to access macrolides and unnatural macrolide derivatives for drug discovery, drug manufacture, and probe development. Typically, efforts to engineer the biosynthesis of macrolides and macrolide analogues in various microbial hosts are hampered by the complexity of macrolide biosynthetic pathways and our limited ability to rationally reprogram type I PKSs and post-PKS machinery. High-throughput approaches based on synthetic biology and directed evolution could overcome this problem by testing the function of large libraries of variants. Yet, methods that can identify mutant enzymes, pathways, and strains that produce the desired macrolide target are not generally available. Here we show that the promiscuous macrolide sensing transcription factor MphR is a powerful platform for engineering variants with tailored properties. We identified variants that displayed improved sensitivity toward erythromycin, tailored the inducer specificity, and significantly improved sensitivity to macrolides that were very poor inducers of the wild-type MphR biosensor. Designer macrolide biosensors should find broad utility and enable applications related to high-throughput synthetic biology and directed evolution of macrolide biosynthesis.
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Affiliation(s)
- Christian M. Kasey
- Department of Chemistry, NC State University, Raleigh, North Carolina 27695, United States
| | - Mounir Zerrad
- Department of Chemistry, NC State University, Raleigh, North Carolina 27695, United States
| | - Yiwei Li
- Department of Chemistry, NC State University, Raleigh, North Carolina 27695, United States
| | - T. Ashton Cropp
- Department of Chemistry, Virginia Commonwealth University, Richmond, Virginia 23284, United States
| | - Gavin J. Williams
- Department of Chemistry, NC State University, Raleigh, North Carolina 27695, United States
- Comparative Medicine Institute, NC State University, Raleigh, North Carolina 27695, United States
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28
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Biosynthesis and production of sabinene: current state and perspectives. Appl Microbiol Biotechnol 2017; 102:1535-1544. [DOI: 10.1007/s00253-017-8695-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Revised: 12/03/2017] [Accepted: 12/04/2017] [Indexed: 01/10/2023]
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29
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A novel DMAPP-responding genetic circuit sensor for high-throughput screening and evolving isoprene synthase. Appl Microbiol Biotechnol 2017; 102:1381-1391. [PMID: 29243081 DOI: 10.1007/s00253-017-8676-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Revised: 11/19/2017] [Accepted: 11/24/2017] [Indexed: 12/14/2022]
Abstract
High-throughput screening is a popular tool for collating biological data which would otherwise require the use of excessive resources. In this study, an artificial genetic circuit sensor responding to dimethylallyl diphosphate (DMAPP) was constructed based on a modified L-arabinose operon for high-throughput screening and isoprene synthase (ispS) evolution in Escherichia coli (E. coli). As a first step, the DNA sequence of the L-arabinose ligand-binding domain (LBD) was replaced with an ispS gene to enable the AraC operon responding to DMAPP, which is the substrate of the IspS enzyme. Then, an enhanced GFP (eGFP) was also introduced as a reporter for pBAD promoter. The expression level of the reporter was monitored using either of the two tools: flow cytometer (FCM) and microplate reader. Sequentially, we observed that a high DMAPP concentration led to low eGFP fluorescence, and the overexpression of ispS gene, which consumes DMAPP, resulted in a high eGFP expression. These results demonstrated that the artificial genetic circuit sensor responded directly to the intracellular concentration of DMAPP, and the expression of IspS enzyme could be positively correlated to the expression level of eGFP. Finally, we identified two IspS mutants with different activities from an ispS gene library and further validated the screening method.
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30
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Vermaas JV, Beckham GT, Crowley MF. Membrane Permeability of Fatty Acyl Compounds Studied via Molecular Simulation. J Phys Chem B 2017; 121:11311-11324. [PMID: 29040809 DOI: 10.1021/acs.jpcb.7b08233] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Interest in fatty acid-derived products as fuel and chemical precursors has grown substantially. Microbes can be genetically engineered to produce fatty acid-derived products that are able to cross host membranes and can be extracted into an applied organic overlay. This process is thought to be passive, with a rate dependent on the chemistry of the crossing compound. The relationship between the chemical composition and the energetics and kinetics of product accumulation within the overlay is not well understood. Through biased and unbiased molecular simulation, we compute the membrane permeability coefficients from production to extraction for different fatty acyl products, including fatty acids, fatty alcohols, fatty aldehydes, alkanes, and alkenes. These simulations identify specific interactions that accelerate the transit of aldehydes across the membrane bilayer relative to other oxidized products, specifically the lack of hydrogen bonds to the surrounding membrane environment. However, since extraction from the outer membrane leaflet into the organic phase is found to be rate limiting for the entire process, we find that fatty alcohols and fatty aldehydes would both manifest similar fluxes into a dodecane overlay under equivalent conditions, outpacing the accumulation of acids or alkanes into the organic phase. Since aldehydes are known to be highly reactive as well as toxic in high quantities, the findings suggest that indeed fatty alcohols are the optimal long-tail fatty acyl product for extraction.
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Affiliation(s)
- Josh V Vermaas
- Biosciences Center, National Renewable Energy Laboratory , Golden, Colorado 80401, United States
| | - Gregg T Beckham
- National Bioenergy Center, National Renewable Energy Laboratory , Golden, Colorado 80401, United States
| | - Michael F Crowley
- Biosciences Center, National Renewable Energy Laboratory , Golden, Colorado 80401, United States
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31
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Towards a sustainable biobased industry - Highlighting the impact of extremophiles. N Biotechnol 2017; 40:144-153. [PMID: 28512003 DOI: 10.1016/j.nbt.2017.05.002] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Revised: 02/28/2017] [Accepted: 05/03/2017] [Indexed: 11/21/2022]
Abstract
The transition of the oil-based economy towards a sustainable economy completely relying on biomass as renewable feedstock requires the concerted action of academia, industry, politics and civil society. An interdisciplinary approach of various fields such as microbiology, molecular biology, chemistry, genetics, chemical engineering and agriculture in addition to cross-sectional technologies such as economy, logistics and digitalization is necessary to meet the future global challenges. The genomic era has contributed significantly to the exploitation of naturés biodiversity also from extreme habitats. By applying modern technologies it is now feasible to deliver robust enzymes (extremozymes) and robust microbial systems that are active at temperatures up to 120°C, at pH 0 and 12 and at 1000bar. In the post-genomic era, different sophisticated "omics" analyses will allow the identification of countless novel enzymes regardless of the lack of cultivability of most microorganisms. Furthermore, elaborate protein-engineering methods are clearing the way towards tailor-made robust biocatalysts. Applying environmentally friendly and efficient biological processes, terrestrial and marine biomass can be converted to high value products e.g. chemicals, building blocks, biomaterials, pharmaceuticals, food, feed and biofuels. Thus, further application of extremophiles has the potential to improve sustainability of existing biotechnological processes towards a greener biobased industry.
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32
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Cheema J, Faraldos JA, O'Maille PE. REVIEW: Epistasis and dominance in the emergence of catalytic function as exemplified by the evolution of plant terpene synthases. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2017; 255:29-38. [PMID: 28131339 DOI: 10.1016/j.plantsci.2016.11.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Revised: 10/17/2016] [Accepted: 11/12/2016] [Indexed: 06/06/2023]
Abstract
Epistasis, the interaction between mutations and the genetic background, is a pervasive force in evolution that is difficult to predict yet derives from a simple principle - biological systems are interconnected. Therefore, one effect may be intimately linked to another, hence interdependent. Untangling epistatic interactions between and within genes is a vibrant area of research. Deriving a mechanistic understanding of epistasis is a major challenge. Particularly, elucidating how epistasis can attenuate the effects of otherwise dominant mutations that control phenotypes. Using the emergence of terpene cyclization in specialized metabolism as an excellent example, this review describes the process of discovery and interpretation of dominance and epistasis in relation to current efforts. Specifically, we outline experimental approaches to isolating epistatic networks of mutations in protein structure, formally quantifying epistatic interactions, then building biochemical models with chemical mechanisms in efforts to achieve an understanding of the physical basis for epistasis. From these models we describe informed conjectures about past evolutionary events that underlie the emergence, divergence and specialization of terpene synthases to illustrate key principles of the constraining forces of epistasis in enzyme function.
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Affiliation(s)
- Jitender Cheema
- John Innes Centre, Computational and Systems Biology, Norwich Research Park, Norwich NR4 7UH, UK.
| | - Juan A Faraldos
- John Innes Centre, Department of Metabolic Biology, Norwich Research Park, Norwich NR4 7UH, UK.
| | - Paul E O'Maille
- John Innes Centre, Department of Metabolic Biology, Norwich Research Park, Norwich NR4 7UH, UK; Institute of Food Research, Food & Health Programme, Norwich Research Park, Norwich NR4 7UA, UK.
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33
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Tashiro M, Fujii A, Kawai-Noma S, Saito K, Umeno D. Directed evolution and expression tuning of geraniol synthase for efficient geraniol production in Escherichia coli. J GEN APPL MICROBIOL 2017; 63:287-295. [DOI: 10.2323/jgam.2017.01.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Miki Tashiro
- Department of Applied Chemistry and Biotechnology, Faculty of Engineering, Chiba University
| | - Akira Fujii
- Department of Applied Chemistry and Biotechnology, Faculty of Engineering, Chiba University
| | - Shigeko Kawai-Noma
- Department of Applied Chemistry and Biotechnology, Faculty of Engineering, Chiba University
| | - Kyoichi Saito
- Department of Applied Chemistry and Biotechnology, Faculty of Engineering, Chiba University
| | - Daisuke Umeno
- Department of Applied Chemistry and Biotechnology, Faculty of Engineering, Chiba University
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34
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Emmerstorfer-Augustin A, Moser S, Pichler H. Screening for improved isoprenoid biosynthesis in microorganisms. J Biotechnol 2016; 235:112-20. [DOI: 10.1016/j.jbiotec.2016.03.051] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2015] [Revised: 03/29/2016] [Accepted: 03/31/2016] [Indexed: 11/26/2022]
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35
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Tashiro M, Kiyota H, Kawai-Noma S, Saito K, Ikeuchi M, Iijima Y, Umeno D. Bacterial Production of Pinene by a Laboratory-Evolved Pinene-Synthase. ACS Synth Biol 2016; 5:1011-20. [PMID: 27247193 DOI: 10.1021/acssynbio.6b00140] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Successful feeding of the substrate geranylpyrophosphate (GPP) to monoterpene synthase is critical to the efficient microbial production of monoterpenes. Overexpression of GPP synthases, metabolic channeling from GPP synthase to terpene synthases, and down-tuning of endogenous competitors have been successfully used to increase the production of monoterpene. Nevertheless, the production of monoterpenes has remained considerably lower than that of hemi-/sesqui-terpenoids. We tested whether it is effective to improve the cellular activity of monoterpene synthases. To this end, we developed a high-throughput screening system to monitor for elevated GPP consumption. Through a single round of mutagenesis and screening, we isolated a pinene synthase variant that outperformed the wild-type (parent) enzyme in multiple contexts in Escherichia coli and cyanobacteria. The purified variant exhibited drastically altered metal dependency, enabling to keep the activity in the cytosol that is manganese-deficient. Coexpression of this variant with mevalonate pathway enzymes, isopentenylpyrophosphate isomerase, and GPP synthase yielded 140 mg/L pinene in a flask culture.
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Affiliation(s)
- Miki Tashiro
- Department of Applied Chemistry and Biotechnology, Faculty of Engineering, Chiba University, 1-33 Yayoi-Cyo, Inage-ku, Chiba 263-8522, Japan
| | - Hiroshi Kiyota
- Department of Biological Sciences, Graduate School of Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Shigeko Kawai-Noma
- Department of Applied Chemistry and Biotechnology, Faculty of Engineering, Chiba University, 1-33 Yayoi-Cyo, Inage-ku, Chiba 263-8522, Japan
| | - Kyoichi Saito
- Department of Applied Chemistry and Biotechnology, Faculty of Engineering, Chiba University, 1-33 Yayoi-Cyo, Inage-ku, Chiba 263-8522, Japan
| | - Masahiko Ikeuchi
- Department of Biological Sciences, Graduate School of Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
- Department of Life
Sciences (Biology), Graduate School of Arts and Science, University of Tokyo, 3-8-1 Meguro-ku, Tokyo 153-8902, Japan
| | - Yoko Iijima
- Department of Nutrition
and Life Science, Kanagawa Institute of Technology, 1030 Shimo-ogino, Atsugi, Kanagawa 243-0292, Japan
| | - Daisuke Umeno
- Department of Applied Chemistry and Biotechnology, Faculty of Engineering, Chiba University, 1-33 Yayoi-Cyo, Inage-ku, Chiba 263-8522, Japan
- Precursory Research
for Embryonic Science and Technology (PRESTO), Japan Science and Technology Agency (JST), 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan
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36
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Lyu Z, Jain R, Smith P, Fetchko T, Yan Y, Whitman WB. Engineering the Autotroph Methanococcus maripaludis for Geraniol Production. ACS Synth Biol 2016; 5:577-81. [PMID: 26886063 DOI: 10.1021/acssynbio.5b00267] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The rapid autotrophic growth of the methanogenic archaeon Methanococcus maripaludis on H2 and CO2 makes it an attractive microbial chassis to inexpensively produce biochemicals. To explore this potential, a synthetic gene encoding geraniol synthase (GES) derived from Ocimum basilicum was cloned into a M. maripaludis expression vector under selection for puromycin resistance. Recombinant expression of GES in M. maripaludis during autotrophic growth on H2/CO2 or formate yielded geraniol at 2.8 and 4.0 mg g(-1) of dry weight, respectively. The yield of geraniol decreased 2-3-fold when organic carbon sources were added to stimulate heterotrophic growth. In the absence of puromycin, geraniol production during autotrophic growth on formate increased to 4.6 mg g(-1) of dry weight. A conceptual model centered on the autotrophic acetyl coenzyme A biosynthetic pathway identified strategies to divert more autotrophic carbon flux to geraniol production.
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Affiliation(s)
- Zhe Lyu
- Department of Microbiology, ‡College of Engineering, and §Department of Biochemistry and Molecular
Biology, University of Georgia, Athens, Georgia 30602, United States
| | - Rachit Jain
- Department of Microbiology, ‡College of Engineering, and §Department of Biochemistry and Molecular
Biology, University of Georgia, Athens, Georgia 30602, United States
| | - Peyton Smith
- Department of Microbiology, ‡College of Engineering, and §Department of Biochemistry and Molecular
Biology, University of Georgia, Athens, Georgia 30602, United States
| | - Travis Fetchko
- Department of Microbiology, ‡College of Engineering, and §Department of Biochemistry and Molecular
Biology, University of Georgia, Athens, Georgia 30602, United States
| | - Yajun Yan
- Department of Microbiology, ‡College of Engineering, and §Department of Biochemistry and Molecular
Biology, University of Georgia, Athens, Georgia 30602, United States
| | - William B. Whitman
- Department of Microbiology, ‡College of Engineering, and §Department of Biochemistry and Molecular
Biology, University of Georgia, Athens, Georgia 30602, United States
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37
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Ferrer M, Martínez-Martínez M, Bargiela R, Streit WR, Golyshina OV, Golyshin PN. Estimating the success of enzyme bioprospecting through metagenomics: current status and future trends. Microb Biotechnol 2016; 9:22-34. [PMID: 26275154 PMCID: PMC4720405 DOI: 10.1111/1751-7915.12309] [Citation(s) in RCA: 127] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2015] [Revised: 06/26/2015] [Accepted: 07/02/2015] [Indexed: 12/01/2022] Open
Abstract
Recent reports have suggested that the establishment of industrially relevant enzyme collections from environmental genomes has become a routine procedure. Across the studies assessed, a mean number of approximately 44 active clones were obtained in an average size of approximately 53,000 clones tested using naïve screening protocols. This number could be significantly increased in shorter times when novel metagenome enzyme sequences obtained by direct sequencing are selected and subjected to high-throughput expression for subsequent production and characterization. The pre-screening of clone libraries by naïve screens followed by the pyrosequencing of the inserts allowed for a 106-fold increase in the success rate of identifying genes encoding enzymes of interest. However, a much longer time, usually on the order of years, is needed from the time of enzyme identification to the establishment of an industrial process. If the hit frequency for the identification of enzymes performing at high turnover rates under real application conditions could be increased while still covering a high natural diversity, the very expensive and time-consuming enzyme optimization phase would likely be significantly shortened. At this point, it is important to review the current knowledge about the success of fine-tuned naïve- and sequence-based screening protocols for enzyme selection and to describe the environments worldwide that have already been subjected to enzyme screen programmes through metagenomic tools. Here, we provide such estimations and suggest the current challenges and future actions needed before environmental enzymes can be successfully introduced into the market.
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Affiliation(s)
- Manuel Ferrer
- Institute of Catalysis, Consejo Superior de Investigaciones Científicas (CSIC), Marie Curie 2, 28049, Madrid, Spain
| | - Mónica Martínez-Martínez
- Institute of Catalysis, Consejo Superior de Investigaciones Científicas (CSIC), Marie Curie 2, 28049, Madrid, Spain
| | - Rafael Bargiela
- Institute of Catalysis, Consejo Superior de Investigaciones Científicas (CSIC), Marie Curie 2, 28049, Madrid, Spain
| | - Wolfgang R Streit
- Biozentrum Klein Flottbek, Universität Hamburg, Ohnhorststraße 18, D-22609, Hamburg, Germany
| | - Olga V Golyshina
- School of Biological Sciences, Bangor University, LL57 2UW, Gwynedd, UK
| | - Peter N Golyshin
- School of Biological Sciences, Bangor University, LL57 2UW, Gwynedd, UK
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38
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Kersten R, Diedrich JK, Yates JR, Noel JP. Mechanism-Based Post-Translational Modification and Inactivation in Terpene Synthases. ACS Chem Biol 2015; 10:2501-11. [PMID: 26378620 PMCID: PMC4655415 DOI: 10.1021/acschembio.5b00539] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Accepted: 08/20/2015] [Indexed: 12/14/2022]
Abstract
Terpenes are ubiquitous natural chemicals with diverse biological functions spanning all three domains of life. In specialized metabolism, the active sites of terpene synthases (TPSs) evolve in shape and reactivity to direct the biosynthesis of a myriad of chemotypes for organismal fitness. As most terpene biosynthesis mechanistically involves highly reactive carbocationic intermediates, the protein surfaces catalyzing these cascade reactions possess reactive regions possibly prone to premature carbocation capture and potentially enzyme inactivation. Here, we show using proteomic and X-ray crystallographic analyses that cationic intermediates undergo capture by conserved active site residues leading to inhibitory self-alkylation. Moreover, the level of cation-mediated inactivation increases with mutation of the active site, upon changes in the size and structure of isoprenoid diphosphate substrates, and alongside increases in reaction temperatures. TPSs that individually synthesize multiple products are less prone to self-alkylation then TPSs possessing relatively high product specificity. In total, the results presented suggest that mechanism-based alkylation represents an overlooked mechanistic pressure during the evolution of cation-derived terpene biosynthesis.
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Affiliation(s)
- Roland
D. Kersten
- Howard
Hughes Medical Institute, Jack H. Skirball Center for Chemical Biology
& Proteomics, The Salk Institute for
Biological Studies, La Jolla, California 92037, United States
| | - Jolene K. Diedrich
- Department
of Chemical Physiology, The Scripps Research
Institute, La Jolla, California 92037, United States
- Vincent
J. Coates Mass Spectrometry Center, The
Salk Institute of Biological Studies, La Jolla, California 92037, United States
| | - John R. Yates
- Department
of Chemical Physiology, The Scripps Research
Institute, La Jolla, California 92037, United States
- Vincent
J. Coates Mass Spectrometry Center, The
Salk Institute of Biological Studies, La Jolla, California 92037, United States
| | - Joseph P. Noel
- Howard
Hughes Medical Institute, Jack H. Skirball Center for Chemical Biology
& Proteomics, The Salk Institute for
Biological Studies, La Jolla, California 92037, United States
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39
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40
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Wang X, Ort DR, Yuan JS. Photosynthetic terpene hydrocarbon production for fuels and chemicals. PLANT BIOTECHNOLOGY JOURNAL 2015; 13:137-46. [PMID: 25626473 DOI: 10.1111/pbi.12343] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2014] [Revised: 12/10/2014] [Accepted: 12/12/2014] [Indexed: 05/19/2023]
Abstract
Photosynthetic hydrocarbon production bypasses the traditional biomass hydrolysis process and represents the most direct conversion of sunlight energy into the next-generation biofuels. As a major class of biologically derived hydrocarbons with diverse structures, terpenes are also valuable in producing a variety of fungible bioproducts in addition to the advanced 'drop-in' biofuels. However, it is highly challenging to achieve the efficient redirection of photosynthetic carbon and reductant into terpene biosynthesis. In this review, we discuss four major scientific and technical barriers for photosynthetic terpene production and recent advances to address these constraints. Collectively, photosynthetic terpene production needs to be optimized in a systematic fashion, in which the photosynthesis improvement, the optimization of terpene biosynthesis pathway, the improvement of key enzymes and the enhancement of sink effect through terpene storage or secretion are all important. New advances in synthetic biology also offer a suite of potential tools to design and engineer photosynthetic terpene platforms. The systemic integration of these solutions may lead to 'disruptive' technologies to enable biofuels and bioproducts with high efficiency, yield and infrastructure compatibility.
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Affiliation(s)
- Xin Wang
- Department of Plant Pathology and Microbiology, Texas A&M University, College Station, TX, USA; Synthetic and Systems Biology Innovation Hub, Texas A&M University, College Station, TX, USA; Institute for Plant Genomics and Biotechnology, Texas A&M University, College Station, TX, USA
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Wang C, Kim JH, Kim SW. Synthetic biology and metabolic engineering for marine carotenoids: new opportunities and future prospects. Mar Drugs 2014; 12:4810-32. [PMID: 25233369 PMCID: PMC4178492 DOI: 10.3390/md12094810] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2014] [Revised: 08/29/2014] [Accepted: 09/01/2014] [Indexed: 11/17/2022] Open
Abstract
Carotenoids are a class of diverse pigments with important biological roles such as light capture and antioxidative activities. Many novel carotenoids have been isolated from marine organisms to date and have shown various utilizations as nutraceuticals and pharmaceuticals. In this review, we summarize the pathways and enzymes of carotenoid synthesis and discuss various modifications of marine carotenoids. The advances in metabolic engineering and synthetic biology for carotenoid production are also reviewed, in hopes that this review will promote the exploration of marine carotenoid for their utilizations.
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Affiliation(s)
- Chonglong Wang
- Division of Applied Life Science (BK21 Plus), PMBBRC, Gyeongsang National University, Jinju 660-701, Korea.
| | - Jung-Hun Kim
- Division of Applied Life Science (BK21 Plus), PMBBRC, Gyeongsang National University, Jinju 660-701, Korea.
| | - Seon-Won Kim
- Division of Applied Life Science (BK21 Plus), PMBBRC, Gyeongsang National University, Jinju 660-701, Korea.
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Liebl W, Angelov A, Juergensen J, Chow J, Loeschcke A, Drepper T, Classen T, Pietruszka J, Ehrenreich A, Streit WR, Jaeger KE. Alternative hosts for functional (meta)genome analysis. Appl Microbiol Biotechnol 2014; 98:8099-109. [PMID: 25091044 DOI: 10.1007/s00253-014-5961-7] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2014] [Revised: 07/14/2014] [Accepted: 07/15/2014] [Indexed: 11/25/2022]
Abstract
Microorganisms are ubiquitous on earth, often forming complex microbial communities in numerous different habitats. Most of these organisms cannot be readily cultivated in the laboratory using standard media and growth conditions. However, it is possible to gain access to the vast genetic, enzymatic, and metabolic diversity present in these microbial communities using cultivation-independent approaches such as sequence- or function-based metagenomics. Function-based analysis is dependent on heterologous expression of metagenomic libraries in a genetically amenable cloning and expression host. To date, Escherichia coli is used in most cases; however, this has the drawback that many genes from heterologous genomes and complex metagenomes are expressed in E. coli either at very low levels or not at all. This review emphasizes the importance of establishing alternative microbial expression systems consisting of different genera and species as well as customized strains and vectors optimized for heterologous expression of membrane proteins, multigene clusters encoding protein complexes or entire metabolic pathways. The use of alternative host-vector systems will complement current metagenomic screening efforts and expand the yield of novel biocatalysts, metabolic pathways, and useful metabolites to be identified from environmental samples.
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Affiliation(s)
- Wolfgang Liebl
- Lehrstuhl für Mikrobiologie, Technische Universität München, Emil-Ramann-Str. 4, 85654, Freising, Germany,
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