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Goris T, Pérez‐Valero Á, Martínez I, Yi D, Fernández‐Calleja L, San León D, Bornscheuer UT, Magadán‐Corpas P, Lombó F, Nogales J. Repositioning microbial biotechnology against COVID-19: the case of microbial production of flavonoids. Microb Biotechnol 2021; 14:94-110. [PMID: 33047877 PMCID: PMC7675739 DOI: 10.1111/1751-7915.13675] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 09/17/2020] [Accepted: 09/18/2020] [Indexed: 12/19/2022] Open
Abstract
Coronavirus-related disease 2019 (COVID-19) became a pandemic in February 2020, and worldwide researchers try to tackle the disease with approved drugs of all kinds, or to develop novel compounds inhibiting viral spreading. Flavonoids, already investigated as antivirals in general, also might bear activities specific for the viral agent causing COVID-19, SARS-CoV-2. Microbial biotechnology and especially synthetic biology may help to produce flavonoids, which are exclusive plant secondary metabolites, at a larger scale or indeed to find novel pharmaceutically active flavonoids. Here, we review the state of the art in (i) antiviral activity of flavonoids specific for coronaviruses and (ii) results derived from computational studies, mostly docking studies mainly inhibiting specific coronaviral proteins such as the 3CL (main) protease, the spike protein or the RNA-dependent RNA polymerase. In the end, we strive towards a synthetic biology pipeline making the fast and tailored production of valuable antiviral flavonoids possible by applying the last concepts of division of labour through co-cultivation/microbial community approaches to the DBTL (Design, Build, Test, Learn) principle.
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Affiliation(s)
- Tobias Goris
- Department of Molecular Toxicology, Research Group Intestinal MicrobiologyGerman Institute of Human Nutrition Potsdam‐RehbrueckeArthur‐Scheunert‐Allee 114‐116NuthetalBrandenburg14558Germany
| | - Álvaro Pérez‐Valero
- Research Unit “Biotechnology in Nutraceuticals and Bioactive Compounds‐BIONUC”Departamento de Biología Funcional, Área de MicrobiologíaUniversidad de OviedoOviedoSpain
- Instituto Universitario de Oncología del Principado de AsturiasOviedoSpain
- Instituto de Investigación Sanitaria del Principado de AsturiasOviedoSpain
| | - Igor Martínez
- Department of Systems BiologyCentro Nacional de BiotecnologíaCSICMadridSpain
| | - Dong Yi
- Department of Biotechnology & Enzyme CatalysisInstitute of BiochemistryUniversity GreifswaldFelix‐Hausdorff‐Str. 4GreifswaldD‐17487Germany
| | - Luis Fernández‐Calleja
- Research Unit “Biotechnology in Nutraceuticals and Bioactive Compounds‐BIONUC”Departamento de Biología Funcional, Área de MicrobiologíaUniversidad de OviedoOviedoSpain
- Instituto Universitario de Oncología del Principado de AsturiasOviedoSpain
- Instituto de Investigación Sanitaria del Principado de AsturiasOviedoSpain
| | - David San León
- Department of Systems BiologyCentro Nacional de BiotecnologíaCSICMadridSpain
| | - Uwe T. Bornscheuer
- Department of Biotechnology & Enzyme CatalysisInstitute of BiochemistryUniversity GreifswaldFelix‐Hausdorff‐Str. 4GreifswaldD‐17487Germany
| | - Patricia Magadán‐Corpas
- Research Unit “Biotechnology in Nutraceuticals and Bioactive Compounds‐BIONUC”Departamento de Biología Funcional, Área de MicrobiologíaUniversidad de OviedoOviedoSpain
- Instituto Universitario de Oncología del Principado de AsturiasOviedoSpain
- Instituto de Investigación Sanitaria del Principado de AsturiasOviedoSpain
| | - Felipe Lombó
- Research Unit “Biotechnology in Nutraceuticals and Bioactive Compounds‐BIONUC”Departamento de Biología Funcional, Área de MicrobiologíaUniversidad de OviedoOviedoSpain
- Instituto Universitario de Oncología del Principado de AsturiasOviedoSpain
- Instituto de Investigación Sanitaria del Principado de AsturiasOviedoSpain
| | - Juan Nogales
- Department of Systems BiologyCentro Nacional de BiotecnologíaCSICMadridSpain
- Interdisciplinary Platform for Sustainable Plastics towards a Circular Economy‐Spanish National Research Council (SusPlast‐CSIC)MadridSpain
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Dymarska M, Janeczko T, Kostrzewa-Susłow E. The Callus of Phaseolus coccineus and Glycine max Biotransform Flavanones into the Corresponding Flavones. Molecules 2020; 25:E5767. [PMID: 33297500 PMCID: PMC7730475 DOI: 10.3390/molecules25235767] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 11/26/2020] [Accepted: 12/05/2020] [Indexed: 01/10/2023] Open
Abstract
In vitro plant cultures are gaining in industrial importance, especially as biocatalysts and as sources of secondary metabolites used in pharmacy. The idea that guided us in our research was to evaluate the biocatalytic potential of newly obtained callus tissue towards flavonoid compounds. In this publication, we describe new ways of using callus cultures in the biotransformations. In the first method, the callus cultures grown on a solid medium are transferred to the water, the reaction medium into which the substrate is introduced. In the second method, biotransformation is carried out on a solid medium by growing callus cultures. In the course of the research, we have shown that the callus obtained from Phaseolus coccineus and Glycine max is capable of converting flavanone, 5-methoxyflavanone and 6-methoxyflavanone into the corresponding flavones.
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Affiliation(s)
- Monika Dymarska
- Department of Chemistry, Wrocław University of Environmental and Life Sciences, Norwida 25, 50-375 Wrocław, Poland; (T.J.); (E.K.-S.)
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53
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Ma J, Gu Y, Xu P. A roadmap to engineering antiviral natural products synthesis in microbes. Curr Opin Biotechnol 2020; 66:140-149. [PMID: 32795662 PMCID: PMC7419324 DOI: 10.1016/j.copbio.2020.07.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Revised: 07/10/2020] [Accepted: 07/15/2020] [Indexed: 12/13/2022]
Abstract
Natural products continue to be the inspirations for us to discover and acquire new drugs. The seemingly unstoppable viruses have kept records high to threaten human health and well-being. The diversity and complexity of natural products (NPs) offer remarkable efficacy and specificity to target viral infection steps and serve as excellent source for antiviral agents. The discovery and production of antiviral NPs remain challenging due to low abundance in their native hosts. Reconstruction of NP biosynthetic pathways in microbes is a promising solution to overcome this limitation. In this review, we surveyed 23 most prominent NPs (from more than 200 antiviral NP candidates) with distinct antiviral mode of actions and summarized the recent metabolic engineering effort to produce these compounds in various microbial hosts. We envision that the scalable and low-cost production of novel antiviral NPs, enabled by metabolic engineering, may light the hope to control and eradicate the deadliest viruses that plague our society and humanity.
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Affiliation(s)
- Jingbo Ma
- Department of Chemical, Biochemical and Environmental Engineering, University of Maryland, Baltimore County, Baltimore, MD, 21250, USA
| | - Yang Gu
- Department of Chemical, Biochemical and Environmental Engineering, University of Maryland, Baltimore County, Baltimore, MD, 21250, USA; Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | - Peng Xu
- Department of Chemical, Biochemical and Environmental Engineering, University of Maryland, Baltimore County, Baltimore, MD, 21250, USA.
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54
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Combining protein and metabolic engineering to construct efficient microbial cell factories. Curr Opin Biotechnol 2020; 66:27-35. [DOI: 10.1016/j.copbio.2020.06.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2020] [Revised: 05/25/2020] [Accepted: 06/01/2020] [Indexed: 11/17/2022]
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55
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Zhu Z, Jiang J, Fa Y. Overcoming the Biological Contamination in Microalgae and Cyanobacteria Mass Cultivations for Photosynthetic Biofuel Production. Molecules 2020; 25:molecules25225220. [PMID: 33182530 PMCID: PMC7698126 DOI: 10.3390/molecules25225220] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 11/06/2020] [Accepted: 11/09/2020] [Indexed: 02/08/2023] Open
Abstract
Microalgae and cyanobacteria have shown significant potential for the development of the next biofuels innovation because of their own characteristics as photosynthetic microorganisms. However, it is confronted with a lot of severe challenges on the economic scaling-up of the microalgae- and cyanobacteria-based biofuels production. One of these major challenges is the lack of a reliable preventing and controlling culture system of biological contamination, which can attack the cell growth or product accumulation causing crashing effects. To increase the commercial viability of microalgae- and cyanobacteria-based biofuels production, overcoming the biological contaminations should be at the top of the priority list. Here, we highlight the importance of two categories of biological contaminations and their controlling strategies in the mass cultivations of microalgae and cyanobacteria, and outline the directions that should be exploited in the future.
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Affiliation(s)
- Zhi Zhu
- The Key Laboratory of Biotechnology for Medicinal Plants of Jiangsu Province and School of Life Science, Jiangsu Normal University, Xuzhou 221116, China;
| | - Jihong Jiang
- The Key Laboratory of Biotechnology for Medicinal Plants of Jiangsu Province and School of Life Science, Jiangsu Normal University, Xuzhou 221116, China;
- Correspondence: (J.J.); (Y.F.)
| | - Yun Fa
- CAS Key Laboratory of Bio-Based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China
- Correspondence: (J.J.); (Y.F.)
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56
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Sui YF, Schütze T, Ouyang LM, Lu H, Liu P, Xiao X, Qi J, Zhuang YP, Meyer V. Engineering cofactor metabolism for improved protein and glucoamylase production in Aspergillus niger. Microb Cell Fact 2020; 19:198. [PMID: 33097040 PMCID: PMC7584080 DOI: 10.1186/s12934-020-01450-w] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Accepted: 10/07/2020] [Indexed: 01/26/2023] Open
Abstract
Background Nicotinamide adenine dinucleotide phosphate (NADPH) is an important cofactor ensuring intracellular redox balance, anabolism and cell growth in all living systems. Our recent multi-omics analyses of glucoamylase (GlaA) biosynthesis in the filamentous fungal cell factory Aspergillus niger indicated that low availability of NADPH might be a limiting factor for GlaA overproduction. Results We thus employed the Design-Build-Test-Learn cycle for metabolic engineering to identify and prioritize effective cofactor engineering strategies for GlaA overproduction. Based on available metabolomics and 13C metabolic flux analysis data, we individually overexpressed seven predicted genes encoding NADPH generation enzymes under the control of the Tet-on gene switch in two A. niger recipient strains, one carrying a single and one carrying seven glaA gene copies, respectively, to test their individual effects on GlaA and total protein overproduction. Both strains were selected to understand if a strong pull towards glaA biosynthesis (seven gene copies) mandates a higher NADPH supply compared to the native condition (one gene copy). Detailed analysis of all 14 strains cultivated in shake flask cultures uncovered that overexpression of the gsdA gene (glucose 6-phosphate dehydrogenase), gndA gene (6-phosphogluconate dehydrogenase) and maeA gene (NADP-dependent malic enzyme) supported GlaA production on a subtle (10%) but significant level in the background strain carrying seven glaA gene copies. We thus performed maltose-limited chemostat cultures combining metabolome analysis for these three isolates to characterize metabolic-level fluctuations caused by cofactor engineering. In these cultures, overexpression of either the gndA or maeA gene increased the intracellular NADPH pool by 45% and 66%, and the yield of GlaA by 65% and 30%, respectively. In contrast, overexpression of the gsdA gene had a negative effect on both total protein and glucoamylase production. Conclusions This data suggests for the first time that increased NADPH availability can indeed underpin protein and especially GlaA production in strains where a strong pull towards GlaA biosynthesis exists. This data also indicates that the highest impact on GlaA production can be engineered on a genetic level by increasing the flux through the pentose phosphate pathway (gndA gene) followed by engineering the flux through the reverse TCA cycle (maeA gene). We thus propose that NADPH cofactor engineering is indeed a valid strategy for metabolic engineering of A. niger to improve GlaA production, a strategy which is certainly also applicable to the rational design of other microbial cell factories.![]()
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Affiliation(s)
- Yu-Fei Sui
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, 200237, People's Republic of China.,Chair of Applied and Molecular Microbiology, Institute of Biotechnology, Technische Universität Berlin, Straße des 17. Juni 135, 10623, Berlin, Germany
| | - Tabea Schütze
- Chair of Applied and Molecular Microbiology, Institute of Biotechnology, Technische Universität Berlin, Straße des 17. Juni 135, 10623, Berlin, Germany
| | - Li-Ming Ouyang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, 200237, People's Republic of China
| | - Hongzhong Lu
- Department of Biology and Biological Engineering, Chalmers University of Technology, Kemivägen 10, 412 96, Gothenburg, Sweden
| | - Peng Liu
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, 200237, People's Republic of China
| | - Xianzun Xiao
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, 200237, People's Republic of China
| | - Jie Qi
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, 200237, People's Republic of China
| | - Ying-Ping Zhuang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, 200237, People's Republic of China.
| | - Vera Meyer
- Chair of Applied and Molecular Microbiology, Institute of Biotechnology, Technische Universität Berlin, Straße des 17. Juni 135, 10623, Berlin, Germany.
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57
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Orsi E, Beekwilder J, Eggink G, Kengen SWM, Weusthuis RA. The transition of Rhodobacter sphaeroides into a microbial cell factory. Biotechnol Bioeng 2020; 118:531-541. [PMID: 33038009 PMCID: PMC7894463 DOI: 10.1002/bit.27593] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Revised: 07/29/2020] [Accepted: 10/09/2020] [Indexed: 12/11/2022]
Abstract
Microbial cell factories are the workhorses of industrial biotechnology and improving their performances can significantly optimize industrial bioprocesses. Microbial strain engineering is often employed for increasing the competitiveness of bio‐based product synthesis over more classical petroleum‐based synthesis. Recently, efforts for strain optimization have been standardized within the iterative concept of “design‐build‐test‐learn” (DBTL). This approach has been successfully employed for the improvement of traditional cell factories like Escherichia coli and Saccharomyces cerevisiae. Within the past decade, several new‐to‐industry microorganisms have been investigated as novel cell factories, including the versatile α‐proteobacterium Rhodobacter sphaeroides. Despite its history as a laboratory strain for fundamental studies, there is a growing interest in this bacterium for its ability to synthesize relevant compounds for the bioeconomy, such as isoprenoids, poly‐β‐hydroxybutyrate, and hydrogen. In this study, we reflect on the reasons for establishing R. sphaeroides as a cell factory from the perspective of the DBTL concept. Moreover, we discuss current and future opportunities for extending the use of this microorganism for the bio‐based economy. We believe that applying the DBTL pipeline for R. sphaeroides will further strengthen its relevance as a microbial cell factory. Moreover, the proposed use of strain engineering via the DBTL approach may be extended to other microorganisms that have not been critically investigated yet for industrial applications.
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Affiliation(s)
- Enrico Orsi
- Bioprocess Engineering, Wageningen University, Wageningen, The Netherlands.,Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm, Germany
| | | | - Gerrit Eggink
- Bioprocess Engineering, Wageningen University, Wageningen, The Netherlands.,Wageningen Food and Biobased Research, Wageningen, The Netherlands
| | - Servé W M Kengen
- Laboratory of Microbiology, Wageningen University, Wageningen, The Netherlands
| | - Ruud A Weusthuis
- Bioprocess Engineering, Wageningen University, Wageningen, The Netherlands
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58
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Current state of aromatics production using yeast: achievements and challenges. Curr Opin Biotechnol 2020; 65:65-74. [DOI: 10.1016/j.copbio.2020.01.008] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Revised: 01/21/2020] [Accepted: 01/24/2020] [Indexed: 12/14/2022]
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59
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Wu Y, Liu Y, Lv X, Li J, Du G, Liu L. Applications of CRISPR in a Microbial Cell Factory: From Genome Reconstruction to Metabolic Network Reprogramming. ACS Synth Biol 2020; 9:2228-2238. [PMID: 32794766 DOI: 10.1021/acssynbio.0c00349] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The well-designed microbial cell factory finds wide applications in chemical, pharmaceutical, and food industries due to its sustainable and environmentally friendly features. Recently, the clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated proteins (CRISPR-Cas) systems have been developed into powerful tools to perform genome editing and transcriptional regulation in prokaryotic and eukaryotic cells. Accordingly, these tools are useful to build microbial cell factories not only by reconstructing the genome but also by reprogramming the metabolic network. In this review, we summarize the recent significant headway and potential uses of the CRISPR technology in the construction of efficient microbial cell factories. Moreover, the future perspectives on the improvement and upgradation of CRISPR-based tools are also discussed.
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Affiliation(s)
- Yaokang Wu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China
- Science Center for Future Foods, Jiangnan University, Wuxi, 214122, China
| | - Yanfeng Liu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China
- Science Center for Future Foods, Jiangnan University, Wuxi, 214122, China
| | - Xueqin Lv
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China
- Science Center for Future Foods, Jiangnan University, Wuxi, 214122, China
| | - Jianghua Li
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China
- Science Center for Future Foods, Jiangnan University, Wuxi, 214122, China
| | - Guocheng Du
- Science Center for Future Foods, Jiangnan University, Wuxi, 214122, China
| | - Long Liu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China
- Science Center for Future Foods, Jiangnan University, Wuxi, 214122, China
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60
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Tan S, Shi F, Liu H, Yu X, Wei S, Fan Z, Li Y. Dynamic Control of 4-Hydroxyisoleucine Biosynthesis by Modified l-Isoleucine Biosensor in Recombinant Corynebacterium glutamicum. ACS Synth Biol 2020; 9:2378-2389. [PMID: 32813974 DOI: 10.1021/acssynbio.0c00127] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
4-Hydroxyisoleucine (4-HIL), a promising drug for treating diabetes, can be synthesized from the self-produced l-isoleucine (Ile) by expressing the Ile dioxygenase gene ido in Corynebacterium glutamicum. However, the requirement of three substrates, Ile, α-ketoglutarate (α-KG), and O2, makes such de novo biosynthesis difficult to be fulfilled effectively under static engineering conditions. In this study, dynamic control of 4-HIL biosynthesis by the Ile biosensor Lrp-PbrnFE was researched. The native PbrnFE promoter of natural Ile biosensor was still weak even under Ile induction. Through tetA dual genetic selection, several modified stronger PbrnFEN promoters were obtained from the synthetic library of the Ile biosensor. Dynamic regulation of ido expression by modified Ile biosensors increased the 4-HIL titer from 24.7 mM to 28.9-74.4 mM. The best strain ST04 produced even a little more 4-HIL than the static strain SN02 overexpressing ido by the strong PtacM promoter (69.7 mM). Further dynamic modulation of α-KG supply in ST04 by expressing different PbrnFEN-controlled odhI decreased the 4-HIL production but increased the l-glutamate or Ile accumulation. However, synergistic modulation of α-KG supply and O2 supply in ST04 by different combinations of PbrnFEN-odhI and PbrnFEN-vgb improved the 4-HIL production significantly, and the highest titer (135.3 mM) was obtained in ST17 strain regulating all the three genes by PbrnFE7. This titer was higher than those of all the static metabolic engineered C. glutamicum strains ever constructed. Therefore, dynamic regulation by modified Ile biosensor is a predominant strategy for enhancing 4-HIL de novo biosynthesis in C. glutamicum.
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Affiliation(s)
- Shuyu Tan
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Feng Shi
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
- International Joint Laboratory on Food Safety, Jiangnan University, Wuxi 214122, China
| | - Haiyan Liu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Xinping Yu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Shuyu Wei
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Zhengyu Fan
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Yongfu Li
- National Engineering Laboratory for Cereal Fermentation Technology, Jiangnan University, Wuxi 214122, China
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61
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Cell-free styrene biosynthesis at high titers. Metab Eng 2020; 61:89-95. [DOI: 10.1016/j.ymben.2020.05.009] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Revised: 05/13/2020] [Accepted: 05/25/2020] [Indexed: 11/18/2022]
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62
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Woodley JM. Towards the sustainable production of bulk-chemicals using biotechnology. N Biotechnol 2020; 59:59-64. [PMID: 32693028 DOI: 10.1016/j.nbt.2020.07.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 07/06/2020] [Accepted: 07/07/2020] [Indexed: 01/06/2023]
Abstract
The design and development of new routes for the production of sustainable bulk-chemicals requires focus on feedstock, conversion technology and downstream product recovery. This brief article discusses some of the constraints with using fermentation and suggests the removal of some constraints by using microbial biocatalysis or enzyme biocatalysis, which give a number of benefits in the context of the requirements for bulk-chemical production. Some potential process concepts are described, for products in the suitable low-price range. These examples (biodiesel, furfurals and amines) are used to illustrate the power of biocatalysis. Suggestions for future research efforts beyond molecular biology, involving process-based concepts, are also discussed.
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Affiliation(s)
- John M Woodley
- Department of Chemical and Biochemical Engineering, Technical University of Denmark, DK-2800, Lyngby, Denmark.
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63
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Recent advances in improving metabolic robustness of microbial cell factories. Curr Opin Biotechnol 2020; 66:69-77. [PMID: 32683192 DOI: 10.1016/j.copbio.2020.06.006] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Revised: 06/12/2020] [Accepted: 06/17/2020] [Indexed: 12/20/2022]
Abstract
Engineering microbial cell factories has been widely applied to produce compounds spanning from intricate natural products to bulk commodities. In each case, host robustness is essential to ensure the reliable and sustainable production of targeted metabolites. However, it can be negatively affected by metabolic burden, pathway toxicity, and harsh environment, resulting in a decreased titer and productivity. Enhanced robustness enables host to have better production performance under complicated growth circumstances. Here, we review current strategies for boosting host robustness, including metabolic balancing, genetic and phenotype stability enhancement, and tolerance engineering. In addition, we discuss the challenges and future perspectives on microbial host engineering for increased robustness.
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64
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Flux controlling technology for central carbon metabolism for efficient microbial bio-production. Curr Opin Biotechnol 2020; 64:169-174. [PMID: 32485613 DOI: 10.1016/j.copbio.2020.04.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 01/27/2020] [Accepted: 04/20/2020] [Indexed: 11/22/2022]
Abstract
Syntheses of many commodities that are produced using microorganisms require cofactors such as ATP and NAD(P)H. Thus, optimization of the flux distribution in central carbon metabolism, which plays a key role in cofactor regeneration, is critical for enhancing the production of the target compounds. Since the intracellular and extracellular conditions change over time in the fermentation process, dynamic control of the metabolic system for maintaining the cellular state appropriately is necessary. Here, we review techniques for detecting the intracellular metabolic state with fluorescent sensors and controlling the flux of central carbon metabolism with optogenetic tools, as well as present a prospect of bio-production processes for fine-tuning the flux distribution.
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65
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Kobayashi S, Kawaguchi H, Shirai T, Ninomiya K, Takahashi K, Kondo A, Tsuge Y. Automatic Redirection of Carbon Flux between Glycolysis and Pentose Phosphate Pathway Using an Oxygen-Responsive Metabolic Switch in Corynebacterium glutamicum. ACS Synth Biol 2020; 9:814-826. [PMID: 32202411 DOI: 10.1021/acssynbio.9b00493] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Controlling the carbon flux into a desired pathway is important for improving product yield in metabolic engineering. After entering a cell, glucose is channeled into glycolysis and the pentose phosphate pathway (PPP), which decreases the yield of target products whose synthesis relies on NADPH as a cofactor. Here, we demonstrate redirection of carbon flux into PPP under aerobic conditions in Corynebacterium glutamicum, achieved by replacing the promoter of glucose 6-phosphate isomerase gene (pgi) with an anaerobic-specific promoter of the lactate dehydrogenase gene (ldhA). The promoter replacement increased the split ratio of carbon flux into PPP from 39 to 83% under aerobic conditions. The titer, yield, and production rate of 1,5-diaminopentane, whose synthesis requires NADPH as a cofactor, were increased by 4.6-, 4.4-, and 2.6-fold, respectively. This is the largest improvement in the production of 1,5-diaminopentane or its precursor, lysine, reported to date. After aerobic cell growth, pgi expression was automatically induced under anaerobic conditions, altering the carbon flux from PPP to glycolysis, to produce succinate in a single metabolically engineered strain. Such an automatic redirection of metabolic pathway using an oxygen-responsive switch enables two-stage fermentation for efficient production of two different compounds by a single strain, potentially reducing the production costs and time for practical applications.
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Affiliation(s)
- Shunsuke Kobayashi
- Graduate School of Natural Science and Technology, Kanazawa University, Kakuma-machi, Kanazawa, Ishikawa 920-1192, Japan
| | - Hideo Kawaguchi
- Graduate School of Science, Technology and Innovation, Kobe University, 1-1 Rokkodaicho, Nada-ku, Kobe, Hyogo 657-8501, Japan
| | - Tomokazu Shirai
- Center for Sustainable Resource Science, RIKEN, 1-7-22, Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan
| | - Kazuaki Ninomiya
- Graduate School of Natural Science and Technology, Kanazawa University, Kakuma-machi, Kanazawa, Ishikawa 920-1192, Japan
- Institute for Frontier Science Initiative, Kanazawa University, Kakuma-machi, Kanazawa, Ishikawa 920-1192, Japan
| | - Kenji Takahashi
- Graduate School of Natural Science and Technology, Kanazawa University, Kakuma-machi, Kanazawa, Ishikawa 920-1192, Japan
| | - Akihiko Kondo
- Graduate School of Science, Technology and Innovation, Kobe University, 1-1 Rokkodaicho, Nada-ku, Kobe, Hyogo 657-8501, Japan
- Center for Sustainable Resource Science, RIKEN, 1-7-22, Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan
| | - Yota Tsuge
- Graduate School of Natural Science and Technology, Kanazawa University, Kakuma-machi, Kanazawa, Ishikawa 920-1192, Japan
- Institute for Frontier Science Initiative, Kanazawa University, Kakuma-machi, Kanazawa, Ishikawa 920-1192, Japan
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66
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Lu Y, Yang Q, Lin Z, Yang X. A modular pathway engineering strategy for the high-level production of β-ionone in Yarrowia lipolytica. Microb Cell Fact 2020; 19:49. [PMID: 32103761 PMCID: PMC7045511 DOI: 10.1186/s12934-020-01309-0] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Accepted: 02/17/2020] [Indexed: 12/21/2022] Open
Abstract
Background The GRAS and oleaginous yeast Yarrowia lipolytica (Y. lipolytica) is an attractive cell factory for the production of chemicals and biofuels. The production of many natural products of commercial interest have been investigated in this cell factory by introducing heterologous biosynthetic pathways and by modifying the endogenous pathways. However, since natural products anabolism involves long pathways and complex regulation, re-channelling carbon into the product of target compounds is still a cumbersome work, and often resulting in low production performance. Results In this work, the carotenogenic genes contained carB and bi-functional carRP from Mucor circinelloides and carotenoid cleavage dioxygenase 1 (CCD1) from Petunia hybrida were introduced to Y. lipolytica and led to the low production of β-ionone of 3.5 mg/L. To further improve the β-ionone synthesis, we implemented a modular engineering strategy for the construction and optimization of a biosynthetic pathway for the overproduction of β-ionone in Y. lipolytica. The strategy involved the enhancement of the cytosolic acetyl-CoA supply and the increase of MVA pathway flux, yielding a β-ionone titer of 358 mg/L in shake-flask fermentation and approximately 1 g/L (~ 280-fold higher than the baseline strain) in fed-batch fermentation. Conclusions An efficient β-ionone producing GRAS Y. lipolytica platform was constructed by combining integrated overexpressed of heterologous and native genes. A modular engineering strategy involved the optimization pathway and fermentation condition was investigated in the engineered strain and the highest β-ionone titer reported to date by a cell factory was achieved. This effective strategy can be adapted to enhance the biosynthesis of other terpenoids in Y. lipolytica.
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Affiliation(s)
- Yanping Lu
- School of Biology and Biological Engineering, South China University of Technology, 382 East Outer Loop Road, University Park, Guangzhou, 510006, China
| | - Qingyu Yang
- School of Biology and Biological Engineering, South China University of Technology, 382 East Outer Loop Road, University Park, Guangzhou, 510006, China
| | - Zhanglin Lin
- School of Biology and Biological Engineering, South China University of Technology, 382 East Outer Loop Road, University Park, Guangzhou, 510006, China.
| | - Xiaofeng Yang
- School of Biology and Biological Engineering, South China University of Technology, 382 East Outer Loop Road, University Park, Guangzhou, 510006, China.
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67
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Genomic Considerations for the Modification of Saccharomyces cerevisiae for Biofuel and Metabolite Biosynthesis. Microorganisms 2020; 8:microorganisms8030321. [PMID: 32110897 PMCID: PMC7143498 DOI: 10.3390/microorganisms8030321] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Revised: 02/02/2020] [Accepted: 02/24/2020] [Indexed: 11/22/2022] Open
Abstract
The growing global population and developing world has put a strain on non-renewable natural resources, such as fuels. The shift to renewable sources will, thus, help meet demands, often through the modification of existing biosynthetic pathways or the introduction of novel pathways into non-native species. There are several useful biosynthetic pathways endogenous to organisms that are not conducive for the scale-up necessary for industrial use. The use of genetic and synthetic biological approaches to engineer these pathways in non-native organisms can help ameliorate these challenges. The budding yeast Saccharomyces cerevisiae offers several advantages for genetic engineering for this purpose due to its widespread use as a model system studied by many researchers. The focus of this review is to present a primer on understanding genomic considerations prior to genetic modification and manipulation of S. cerevisiae. The choice of a site for genetic manipulation can have broad implications on transcription throughout a region and this review will present the current understanding of position effects on transcription.
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68
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Liu D, Geiselman GM, Coradetti S, Cheng YF, Kirby J, Prahl JP, Jacobson O, Sundstrom ER, Tanjore D, Skerker JM, Gladden J. Exploiting nonionic surfactants to enhance fatty alcohol production in Rhodosporidium toruloides. Biotechnol Bioeng 2020; 117:1418-1425. [PMID: 31981215 PMCID: PMC7187362 DOI: 10.1002/bit.27285] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Revised: 12/23/2019] [Accepted: 01/22/2020] [Indexed: 01/13/2023]
Abstract
Fatty alcohols (FOHs) are important feedstocks in the chemical industry to produce detergents, cosmetics, and lubricants. Microbial production of FOHs has become an attractive alternative to production in plants and animals due to growing energy demands and environmental concerns. However, inhibition of cell growth caused by intracellular FOH accumulation is one major issue that limits FOH titers in microbial hosts. In addition, identification of FOH‐specific exporters remains a challenge and previous studies towards this end are limited. To alleviate the toxicity issue, we exploited nonionic surfactants to promote the export of FOHs in Rhodosporidium toruloides, an oleaginous yeast that is considered an attractive next‐generation host for the production of fatty acid‐derived chemicals. Our results showed FOH export efficiency was dramatically improved and the growth inhibition was alleviated in the presence of small amounts of tergitol and other surfactants. As a result, FOH titers increase by 4.3‐fold at bench scale to 352.6 mg/L. With further process optimization in a 2‐L bioreactor, the titer was further increased to 1.6 g/L. The method we show here can potentially be applied to other microbial hosts and may facilitate the commercialization of microbial FOH production.
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Affiliation(s)
- Di Liu
- Department of Biomass Science and Conversion Technology, Sandia National Laboratories, Livermore, California.,Department of Energy, Agile BioFoundry, Emeryville, California
| | - Gina M Geiselman
- Department of Biomass Science and Conversion Technology, Sandia National Laboratories, Livermore, California.,Department of Energy, Agile BioFoundry, Emeryville, California
| | - Samuel Coradetti
- Department of Biomass Science and Conversion Technology, Sandia National Laboratories, Livermore, California.,Department of Energy, Agile BioFoundry, Emeryville, California
| | - Ya-Fang Cheng
- QB3-Berkeley, University of California, Berkeley, California
| | - James Kirby
- Department of Biomass Science and Conversion Technology, Sandia National Laboratories, Livermore, California.,Department of Energy, Agile BioFoundry, Emeryville, California
| | - Jan-Philip Prahl
- Department of Energy, Agile BioFoundry, Emeryville, California.,Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, California.,Advanced Biofuels and Bioproducts Process Development Unit, Lawrence Berkeley National Laboratory, Emeryville, California
| | - Oslo Jacobson
- Department of Energy, Agile BioFoundry, Emeryville, California.,Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, California.,Advanced Biofuels and Bioproducts Process Development Unit, Lawrence Berkeley National Laboratory, Emeryville, California
| | - Eric R Sundstrom
- Department of Energy, Agile BioFoundry, Emeryville, California.,Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, California.,Advanced Biofuels and Bioproducts Process Development Unit, Lawrence Berkeley National Laboratory, Emeryville, California
| | - Deepti Tanjore
- Department of Energy, Agile BioFoundry, Emeryville, California.,Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, California.,Advanced Biofuels and Bioproducts Process Development Unit, Lawrence Berkeley National Laboratory, Emeryville, California
| | | | - John Gladden
- Department of Biomass Science and Conversion Technology, Sandia National Laboratories, Livermore, California.,Department of Energy, Agile BioFoundry, Emeryville, California.,Joint BioEnergy Institute, Emeryville, California
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69
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Wang B, Zhao H. Unleashing the power of energy storage: Engineering β-oxidation pathways for polyketide production. Synth Syst Biotechnol 2020; 5:21-22. [PMID: 32042931 PMCID: PMC6997112 DOI: 10.1016/j.synbio.2020.01.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2020] [Accepted: 01/13/2020] [Indexed: 01/06/2023] Open
Abstract
Overproduction of polyketides has been a challenge for metabolic engineering for decades. However, recent studies have demonstrated that in both native host and heterologous host, engineering β -oxidation pathways can lead to dramatic improvement of polyketide production.
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Affiliation(s)
- Bin Wang
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Huimin Zhao
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA.,Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA.,Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL, USA.,Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, IL, USA.,Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA
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70
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Chu N, Liang Q, Jiang Y, Zeng RJ. Microbial electrochemical platform for the production of renewable fuels and chemicals. Biosens Bioelectron 2020; 150:111922. [DOI: 10.1016/j.bios.2019.111922] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Revised: 11/23/2019] [Accepted: 11/25/2019] [Indexed: 12/01/2022]
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71
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Deng H, Bai Y, Fan TP, Zheng X, Cai Y. Advanced strategy for metabolite exploration in filamentous fungi. Crit Rev Biotechnol 2020; 40:180-198. [PMID: 31906740 DOI: 10.1080/07388551.2019.1709798] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Filamentous fungi comprise an abundance of gene clusters that encode high-value metabolites, whereas affluent gene clusters remain silent during laboratory conditions. Complex cellular metabolism further limits these metabolite yields. Therefore, diverse strategies such as genetic engineering and chemical mutagenesis have been developed to activate these cryptic pathways and improve metabolite productivity. However, lower efficiencies of gene modifications and screen tools delayed the above processes. To address the above issues, this review describes an alternative design-construction evaluation optimization (DCEO) approach. The DCEO tool provides theoretical and practical principles to identify potential pathways, modify endogenous pathways, integrate exogenous pathways, and exploit novel pathways for their diverse metabolites and desirable productivities. This DCEO method also offers different tactics to balance the cellular metabolisms, facilitate the genetic engineering, and exploit the scalable metabolites in filamentous fungi.
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Affiliation(s)
- Huaxiang Deng
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, Jiangsu, China.,Center for Synthetic Biochemistry, Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technologies, Shenzhen, China
| | - Yajun Bai
- College of Life Sciences, Northwest University, Xi'an, Shanxi, China
| | - Tai-Ping Fan
- Department of Pharmacology, University of Cambridge, Cambridge, UK
| | - Xiaohui Zheng
- College of Life Sciences, Northwest University, Xi'an, Shanxi, China
| | - Yujie Cai
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, Jiangsu, China
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72
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Engineering 4-coumaroyl-CoA derived polyketide production in Yarrowia lipolytica through a β-oxidation mediated strategy. Metab Eng 2019; 57:174-181. [PMID: 31740389 DOI: 10.1016/j.ymben.2019.11.006] [Citation(s) in RCA: 90] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Revised: 11/13/2019] [Accepted: 11/14/2019] [Indexed: 12/20/2022]
Abstract
Polyketides are a diverse class of molecules sought after for their valuable properties, including as potential pharmaceuticals. Previously, we demonstrated that the oleaginous yeast Yarrowia lipolytica is an optimal host for production of the simple polyketide, triacetic acid lactone (TAL). We here expand the capacities of this host by overcoming previous media challenges and enabling production of more complex polyketides. Specifically, we employ a β-oxidation related strategy to improve polyketide production directly from defined media. Beyond TAL production, we establish biosynthesis of the 4-coumaroyl-CoA derived polyketides: naringenin, resveratrol, and bisdemethoxycurcumin, as well as the diketide intermediate, (E)-5-(4-hydroxyphenyl)-3-oxopent-4-enoic acid. In this background, we enable high-level de novo production of naringenin through import of both a heterologous pathway and a mutant Y. lipolytica allele. In doing so, we generated an averaged maximum titer of 898 mg/L naringenin, the highest titer reported to date in any host. These results demonstrate that Y. lipolytica is an ideal polyketide production host for more complex 4-coumaroyl-CoA derived products.
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73
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Dahabieh MS, Thevelein JM, Gibson B. Multimodal Microorganism Development: Integrating Top-Down Biological Engineering with Bottom-Up Rational Design. Trends Biotechnol 2019; 38:241-253. [PMID: 31653446 DOI: 10.1016/j.tibtech.2019.09.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Revised: 09/28/2019] [Accepted: 09/30/2019] [Indexed: 12/12/2022]
Abstract
Biological engineering has unprecedented potential to solve society's most pressing challenges. Engineering approaches must consider complex technical, economic, and social factors. This requires methods that confer gene/pathway-level functionality and organism-level robustness in rapid and cost-effective ways. This article compares foundational engineering approaches - bottom-up, gene-targeted engineering, and top-down, whole-genome engineering - and identifies significant complementarity between them. Cases drawn from engineering Saccharomyces cerevisiae exemplify the synergy of a combined approach. Indeed, multimodal engineering streamlines strain development by leveraging the complementarity of whole-genome and gene-targeted engineering to overcome the gap in design knowledge that restricts rational design. As biological engineers target more complex systems, this dual-track approach is poised to become an increasingly important tool to realize the promise of synthetic biology.
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Affiliation(s)
- Matthew S Dahabieh
- Renaissance BioScience, 410-2389 Health Sciences Mall, Vancouver, BC V6T1Z3, Canada
| | - Johan M Thevelein
- Laboratory of Molecular Cell Biology, Institute of Botany and Microbiology, Katholieke Universiteit (KU) Leuven, Leuven, Belgium; Center for Microbiology, Vlaams Instituut voor Biotechnologie (VIB), Kasteelpark Arenberg 31, B-3001 Leuven-Heverlee, Flanders, Belgium
| | - Brian Gibson
- VTT Technical Research Centre of Finland, Tietotie 2, VTT, PO Box 1000, FI-02044 Espoo, Finland.
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