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Yuan Y, Al Bulushi T, Sastry AV, Sancar C, Szubin R, Golden SS, Palsson BO. Machine learning reveals the transcriptional regulatory network and circadian dynamics of Synechococcus elongatus PCC 7942. Proc Natl Acad Sci U S A 2024; 121:e2410492121. [PMID: 39269777 PMCID: PMC11420160 DOI: 10.1073/pnas.2410492121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2024] [Accepted: 08/05/2024] [Indexed: 09/15/2024] Open
Abstract
Synechococcus elongatus is an important cyanobacterium that serves as a versatile and robust model for studying circadian biology and photosynthetic metabolism. Its transcriptional regulatory network (TRN) is of fundamental interest, as it orchestrates the cell's adaptation to the environment, including its response to sunlight. Despite the previous characterization of constituent parts of the S. elongatus TRN, a comprehensive layout of its topology remains to be established. Here, we decomposed a compendium of 300 high-quality RNA sequencing datasets of the model strain PCC 7942 using independent component analysis. We obtained 57 independently modulated gene sets, or iModulons, that explain 67% of the variance in the transcriptional response and 1) accurately reflect the activity of known transcriptional regulations, 2) capture functional components of photosynthesis, 3) provide hypotheses for regulon structures and functional annotations of poorly characterized genes, and 4) describe the transcriptional shifts under dynamic light conditions. This transcriptome-wide analysis of S. elongatus provides a quantitative reconstruction of the TRN and presents a knowledge base that can guide future investigations. Our systems-level analysis also provides a global TRN structure for S. elongatus PCC 7942.
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Affiliation(s)
- Yuan Yuan
- Shu Chien-Gene Lay Department of Bioengineering, University of California San Diego, La Jolla, CA 92093
| | - Tahani Al Bulushi
- Shu Chien-Gene Lay Department of Bioengineering, University of California San Diego, La Jolla, CA 92093
| | - Anand V Sastry
- Shu Chien-Gene Lay Department of Bioengineering, University of California San Diego, La Jolla, CA 92093
| | - Cigdem Sancar
- Center for Circadian Biology, University of California, San Diego, La Jolla, CA 92093
| | - Richard Szubin
- Shu Chien-Gene Lay Department of Bioengineering, University of California San Diego, La Jolla, CA 92093
| | - Susan S Golden
- Center for Circadian Biology, University of California, San Diego, La Jolla, CA 92093
- Department of Molecular Biology, University of California, San Diego, La Jolla, CA 92093
| | - Bernhard O Palsson
- Shu Chien-Gene Lay Department of Bioengineering, University of California San Diego, La Jolla, CA 92093
- Bioinformatics and Systems Biology Program, University of California, San Diego, La Jolla, CA 92093
- Department of Pediatrics, University of California, San Diego, La Jolla, CA 92093
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kongens, Lyngby 2800, Denmark
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2
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Gao H, Wang Y, Huang Z, Yu F, Hu X, Ning D, Xu X. Development of Leptolyngbya sp. BL0902 into a model organism for synthetic biological research in filamentous cyanobacteria. Front Microbiol 2024; 15:1409771. [PMID: 39104590 PMCID: PMC11298460 DOI: 10.3389/fmicb.2024.1409771] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2024] [Accepted: 07/10/2024] [Indexed: 08/07/2024] Open
Abstract
Cyanobacteria have great potential in CO2-based bio-manufacturing and synthetic biological studies. The filamentous cyanobacterium, Leptolyngbya sp. strain BL0902, is comparable to Arthrospira (Spirulina) platensis in commercial-scale cultivation while proving to be more genetically tractable. Here, we report the analyses of the whole genome sequence, gene inactivation/overexpression in the chromosome and deletion of non-essential chromosomal regions in this strain. The genetic manipulations were performed via homologous double recombination using either an antibiotic resistance marker or the CRISPR/Cpf1 editing system for positive selection. A desD-overexpressing strain produced γ-linolenic acid in an open raceway photobioreactor with the productivity of 0.36 g·m-2·d-1. Deletion mutants of predicted patX and hetR, two genes with opposite effects on cell differentiation in heterocyst-forming species, were used to demonstrate an analysis of the relationship between regulatory genes in the non-heterocystous species. Furthermore, a 50.8-kb chromosomal region was successfully deleted in BL0902 with the Cpf1 system. These results supported that BL0902 can be developed into a stable photosynthetic cell factory for synthesizing high value-added products, or used as a model strain for investigating the functions of genes that are unique to filamentous cyanobacteria, and could be systematically modified into a genome-streamlined chassis for synthetic biological purposes.
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Affiliation(s)
- Hong Gao
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Yali Wang
- School of Life Sciences, Central China Normal University, Wuhan, China
| | - Ziling Huang
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Feiqi Yu
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- School of Life Sciences, Central China Normal University, Wuhan, China
| | - Xi Hu
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Degang Ning
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Xudong Xu
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- School of Life Sciences, Central China Normal University, Wuhan, China
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3
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Liu X, Tang K, Hu J. Application of Cyanobacteria as Chassis Cells in Synthetic Biology. Microorganisms 2024; 12:1375. [PMID: 39065143 PMCID: PMC11278661 DOI: 10.3390/microorganisms12071375] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2024] [Revised: 06/30/2024] [Accepted: 07/02/2024] [Indexed: 07/28/2024] Open
Abstract
Synthetic biology is an exciting new area of research that combines science and engineering to design and build new biological functions and systems. Predictably, with the development of synthetic biology, more efficient and economical photosynthetic microalgae chassis will be successfully constructed, making it possible to break through laboratory research into large-scale industrial applications. The synthesis of a range of biochemicals has been demonstrated in cyanobacteria; however, low product titers are the biggest barrier to the commercialization of cyanobacterial biotechnology. This review summarizes the applied improvement strategies from the perspectives of cyanobacteria chassis cells and synthetic biology. The harvest advantages of cyanobacterial products and the latest progress in improving production strategies are discussed according to the product status. As cyanobacteria synthetic biology is still in its infancy, apart from the achievements made, the difficulties and challenges in the application and development of cyanobacteria genetic tool kits in biochemical synthesis, environmental monitoring, and remediation were assessed.
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Affiliation(s)
| | | | - Jinlu Hu
- School of Life Sciences, Northwestern Polytechnical University, Xi’an 710072, China; (X.L.); (K.T.)
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4
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Zhou J, Xu S, Li H, Xi H, Cheng W, Yang C. A Ribulose-5-phosphate Shunt from the Calvin-Benson Cycle to Methylerythritol Phosphate Pathway for Enhancing Photosynthetic Terpenoid Production. ACS Synth Biol 2024; 13:876-887. [PMID: 38362836 DOI: 10.1021/acssynbio.3c00675] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2024]
Abstract
Cyanobacteria are attractive hosts for photosynthetic terpenoid production, using CO2 as the sole carbon source. Although the methylerythritol phosphate (MEP) pathway is superior to the mevalonate pathway for cyanobacterial terpenoid synthesis, the first reaction of the MEP pathway, which is catalyzed by 1-deoxy-d-xylulose-5-phosphate (DXP) synthase, involves complex regulation and carbon loss. Here, we constructed a direct route linking ribulose-5-phosphate (Ru5P) in the Calvin-Benson (CB) cycle with DXP in the MEP pathway in a cyanobacterium to increase the terpenoid yield from CO2 and bypass the DXS-targeted regulations. By employing the adaptive laboratory evolution, we identified new RibB variants including RibB 90-92del with a high activity of synthesizing DXP from Ru5P. These RibB variants were introduced into Synechococcus elongatus, resulting in the significantly increased photosynthetic production of isopentenol. The 13C tracer experiments demonstrated a direct carbon flow from Ru5P in the CB cycle to the MEP pathway; thus, this direct route was denoted as the Ru5P shunt. The strain harboring the Ru5P shunt produced 105.2 mg L-1 of isopentenol with an average rate of 17.5 mg L-1 d-1 under continuous light conditions, which is higher than those ever reported for five-carbon alcohol production by photoautotrophic microorganisms. Utilization of the Ru5P shunt in cyanobacterial cells also improved the pinene production, which demonstrates that this shunt can be used to enhance the photosynthetic production of diverse terpenoids.
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Affiliation(s)
- Jie Zhou
- CAS-Key Laboratory of Synthetic Biology, Key Laboratory of Plant Carbon Capture, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Suxian Xu
- CAS-Key Laboratory of Synthetic Biology, Key Laboratory of Plant Carbon Capture, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Hu Li
- CAS-Key Laboratory of Synthetic Biology, Key Laboratory of Plant Carbon Capture, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Huachao Xi
- CAS-Key Laboratory of Synthetic Biology, Key Laboratory of Plant Carbon Capture, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wenbo Cheng
- CAS-Key Laboratory of Synthetic Biology, Key Laboratory of Plant Carbon Capture, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Chen Yang
- CAS-Key Laboratory of Synthetic Biology, Key Laboratory of Plant Carbon Capture, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China
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5
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Rautela A, Yadav I, Gangwar A, Chatterjee R, Kumar S. Photosynthetic production of α-farnesene by engineered Synechococcus elongatus UTEX 2973 from carbon dioxide. BIORESOURCE TECHNOLOGY 2024; 396:130432. [PMID: 38346593 DOI: 10.1016/j.biortech.2024.130432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Revised: 02/05/2024] [Accepted: 02/06/2024] [Indexed: 02/16/2024]
Abstract
Cyanobacteria are the prospective biosolar cell factories to produce a range of bioproducts through CO2 sequestration. Farnesene is a sesquiterpene with an array of applications in biofuels, pest management, cosmetics, flavours and fragrances. This is the first time a codon-optimized farnesene synthase (AFS) gene is engineered into the genomic neutral site of Synechococcus elongatus UTEX 2973 for farnesene synthesis through its endogenous methylerythritol phosphate (MEP) pathway, rendering UTEX AFS strain. Similarly, bottleneck gene(s) of the MEP pathway, 1-deoxy-D-xylulose-5-phosphate synthase (dxs) and/or fusion of isopentenyl diphosphate isomerase and farnesyl diphosphate synthase (idispA) were engineered engendering UTEX AFS::dxs, UTEX AFS::idispA and UTEX AFS::dxs::idispA strains. UTEX AFS::dxs::idispA achieves farnesene productivity of 2.57 mg/L/day, the highest among engineered cyanobacterial strains studied so far. It demonstrates farnesene production, which is 31.3-times higher than the UTEX AFS strain. Moreover, the engineered strains show similar productivity over a three-month period, stipulating the genetic stability of the strains.
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Affiliation(s)
- Akhil Rautela
- Biofuel Research Laboratory, School of Biochemical Engineering, IIT(BHU) Varanasi, Varanasi 221005, Uttar Pradesh, India
| | - Indrajeet Yadav
- Biofuel Research Laboratory, School of Biochemical Engineering, IIT(BHU) Varanasi, Varanasi 221005, Uttar Pradesh, India
| | - Agendra Gangwar
- Biofuel Research Laboratory, School of Biochemical Engineering, IIT(BHU) Varanasi, Varanasi 221005, Uttar Pradesh, India
| | - Rishika Chatterjee
- Biofuel Research Laboratory, School of Biochemical Engineering, IIT(BHU) Varanasi, Varanasi 221005, Uttar Pradesh, India
| | - Sanjay Kumar
- Biofuel Research Laboratory, School of Biochemical Engineering, IIT(BHU) Varanasi, Varanasi 221005, Uttar Pradesh, India.
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6
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Melis A, Hidalgo Martinez DA, Betterle N. Perspectives of cyanobacterial cell factories. PHOTOSYNTHESIS RESEARCH 2023:10.1007/s11120-023-01056-4. [PMID: 37966575 DOI: 10.1007/s11120-023-01056-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Accepted: 10/13/2023] [Indexed: 11/16/2023]
Abstract
Cyanobacteria are prokaryotic photosynthetic microorganisms that can generate, in addition to biomass, useful chemicals and proteins/enzymes, essentially from sunlight, carbon dioxide, and water. Selected aspects of cyanobacterial production (isoprenoids and high-value proteins) and scale-up methods suitable for product generation and downstream processing are addressed in this review. The work focuses on the challenge and promise of specialty chemicals and proteins production, with isoprenoid products and biopharma proteins as study cases, and the challenges encountered in the expression of recombinant proteins/enzymes, which underline the essence of synthetic biology with these microorganisms. Progress and the current state-of-the-art in these targeted topics are emphasized.
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Affiliation(s)
- Anastasios Melis
- Department of Plant and Microbial Biology, University of California, MC-3102, Berkeley, CA, 94720-3102, USA.
| | - Diego Alberto Hidalgo Martinez
- Department of Biology, Healthcare and the Environment, Faculty of Pharmacy and Food Sciences, University of Barcelona, Barcelona, Spain
| | - Nico Betterle
- SoLELab, Department of Biotechnology, University of Verona, 37134, Verona, Italy
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7
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Germann AT, Nakielski A, Dietsch M, Petzel T, Moser D, Triesch S, Westhoff P, Axmann IM. A systematic overexpression approach reveals native targets to increase squalene production in Synechocystis sp. PCC 6803. FRONTIERS IN PLANT SCIENCE 2023; 14:1024981. [PMID: 37324717 PMCID: PMC10266222 DOI: 10.3389/fpls.2023.1024981] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Accepted: 04/28/2023] [Indexed: 06/17/2023]
Abstract
Cyanobacteria are a promising platform for the production of the triterpene squalene (C30), a precursor for all plant and animal sterols, and a highly attractive intermediate towards triterpenoids, a large group of secondary plant metabolites. Synechocystis sp. PCC 6803 natively produces squalene from CO2 through the MEP pathway. Based on the predictions of a constraint-based metabolic model, we took a systematic overexpression approach to quantify native Synechocystis gene's impact on squalene production in a squalene-hopene cyclase gene knock-out strain (Δshc). Our in silico analysis revealed an increased flux through the Calvin-Benson-Bassham cycle in the Δshc mutant compared to the wildtype, including the pentose phosphate pathway, as well as lower glycolysis, while the tricarboxylic acid cycle predicted to be downregulated. Further, all enzymes of the MEP pathway and terpenoid synthesis, as well as enzymes from the central carbon metabolism, Gap2, Tpi and PyrK, were predicted to positively contribute to squalene production upon their overexpression. Each identified target gene was integrated into the genome of Synechocystis Δshc under the control of the rhamnose-inducible promoter Prha. Squalene production was increased in an inducer concentration dependent manner through the overexpression of most predicted genes, which are genes of the MEP pathway, ispH, ispE, and idi, leading to the greatest improvements. Moreover, we were able to overexpress the native squalene synthase gene (sqs) in Synechocystis Δshc, which reached the highest production titer of 13.72 mg l-1 reported for squalene in Synechocystis sp. PCC 6803 so far, thereby providing a promising and sustainable platform for triterpene production.
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Affiliation(s)
- Anna T. Germann
- Institute for Synthetic Microbiology, Department of Biology, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Andreas Nakielski
- Institute for Synthetic Microbiology, Department of Biology, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Maximilian Dietsch
- Institute for Synthetic Microbiology, Department of Biology, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Tim Petzel
- Institute for Synthetic Microbiology, Department of Biology, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Daniel Moser
- Institute for Plant Sciences and Cluster of Excellence on Plant Sciences (CEPLAS), University of Cologne, Cologne, Germany
| | - Sebastian Triesch
- Institute of Plant Biochemistry, Cluster of Excellence on Plant Science (CEPLAS), Heinrich Heine University, Düsseldorf, Germany
| | - Philipp Westhoff
- Plant Metabolism and Metabolomics Laboratory, Cluster of Excellence on Plant Sciences (CEPLAS), Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Ilka M. Axmann
- Institute for Synthetic Microbiology, Department of Biology, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
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8
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Chen AY, Ku JT, Tsai TP, Hung JJ, Hung BC, Lan EI. Metabolic Engineering Design Strategies for Increasing Carbon Fluxes Relevant for Biosynthesis in Cyanobacteria. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2023; 183:105-144. [PMID: 37093259 DOI: 10.1007/10_2023_218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/25/2023]
Abstract
Cyanobacteria are promising microbial cell factories for the direct production of biochemicals and biofuels from CO2. Through genetic and metabolic engineering, they can be modified to produce a variety of both natural and non-natural compounds. To enhance the yield of these products, various design strategies have been developed. In this chapter, strategies used to enhance metabolic fluxes towards common precursors used in biosynthesis, including pyruvate, acetyl-CoA, malonyl-CoA, TCA cycle intermediates, and aromatics, are discussed. Additionally, strategies related to cofactor availability and mixotrophic conditions for bioproduction are also summarize.
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Affiliation(s)
- Arvin Y Chen
- Institute of Molecular Medicine and Bioengineering, National Yang Ming Chiao Tung University, Hsinchu City, Taiwan
| | - Jason T Ku
- Institute of Molecular Medicine and Bioengineering, National Yang Ming Chiao Tung University, Hsinchu City, Taiwan
| | - Teresa P Tsai
- Institute of Biomedical Engineering, National Yang Ming Chiao Tung University, Hsinchu City, Taiwan
| | - Jenny J Hung
- Institute of Molecular Medicine and Bioengineering, National Yang Ming Chiao Tung University, Hsinchu City, Taiwan
| | - Billy C Hung
- Institute of Molecular Medicine and Bioengineering, National Yang Ming Chiao Tung University, Hsinchu City, Taiwan
| | - Ethan I Lan
- Department of Biological Science and Technology, National Yang Ming Chiao Tung University, Hsinchu City, Taiwan.
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9
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Tan C, Xu P, Tao F. Carbon-negative synthetic biology: challenges and emerging trends of cyanobacterial technology. Trends Biotechnol 2022; 40:1488-1502. [PMID: 36253158 DOI: 10.1016/j.tibtech.2022.09.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 09/05/2022] [Accepted: 09/20/2022] [Indexed: 11/06/2022]
Abstract
Global warming and climate instability have spurred interest in using renewable carbon resources for the sustainable production of chemicals. Cyanobacteria are ideal cellular factories for carbon-negative production of chemicals owing to their great potentials for directly utilizing light and CO2 as sole energy and carbon sources, respectively. However, several challenges in adapting cyanobacterial technology to industry, such as low productivity, poor tolerance, and product harvesting difficulty, remain. Synthetic biology may finally address these challenges. Here, we summarize recent advances in the production of value-added chemicals using cyanobacterial cell factories, particularly in carbon-negative synthetic biology and emerging trends in cyanobacterial applications. We also propose several perspectives on the future development of cyanobacterial technology for commercialization.
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Affiliation(s)
- Chunlin Tan
- The State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic and Developmental Sciences and School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Ping Xu
- The State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic and Developmental Sciences and School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Fei Tao
- The State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic and Developmental Sciences and School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China.
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10
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Rautela A, Kumar S. Engineering plant family TPS into cyanobacterial host for terpenoids production. PLANT CELL REPORTS 2022; 41:1791-1803. [PMID: 35789422 PMCID: PMC9253243 DOI: 10.1007/s00299-022-02892-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Accepted: 06/05/2022] [Indexed: 05/03/2023]
Abstract
Terpenoids are synthesized naturally by plants as secondary metabolites, and are diverse and complex in structure with multiple applications in bioenergy, food, cosmetics, and medicine. This makes the production of terpenoids such as isoprene, β-phellandrene, farnesene, amorphadiene, and squalene valuable, owing to which their industrial demand cannot be fulfilled exclusively by plant sources. They are synthesized via the Methylerythritol phosphate pathway (MEP) and the Mevalonate pathway (MVA), both existing in plants. The advent of genetic engineering and the latest accomplishments in synthetic biology and metabolic engineering allow microbial synthesis of terpenoids. Cyanobacteria manifest to be the promising hosts for this, utilizing sunlight and CO2. Cyanobacteria possess MEP pathway to generate precursors for terpenoid synthesis. The terpenoid synthesis can be amplified by overexpressing the MEP pathway and engineering MVA pathway genes. According to the desired terpenoid, terpene synthases unique to the plant kingdom must be incorporated in cyanobacteria. Engineering an organism to be used as a cell factory comes with drawbacks such as hampered cell growth and disturbance in metabolic flux. This review set forth a comparison between MEP and MVA pathways, strategies to overexpress these pathways with their challenges.
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Affiliation(s)
- Akhil Rautela
- School of Biochemical Engineering, IIT (BHU), Varanasi, 221005, Uttar Pradesh, India
| | - Sanjay Kumar
- School of Biochemical Engineering, IIT (BHU), Varanasi, 221005, Uttar Pradesh, India.
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11
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Klaus O, Hilgers F, Nakielski A, Hasenklever D, Jaeger KE, Axmann IM, Drepper T. Engineering phototrophic bacteria for the production of terpenoids. Curr Opin Biotechnol 2022; 77:102764. [PMID: 35932511 DOI: 10.1016/j.copbio.2022.102764] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 06/24/2022] [Accepted: 06/30/2022] [Indexed: 12/13/2022]
Abstract
With more than 80 000 compounds, terpenoids represent one of the largest classes of secondary metabolites naturally produced by various plants and other organisms. Owing to the tremendous structural diversity, they offer a wide range of properties relevant for biotechnological and pharmaceutical applications. In this context, heterologous terpenoid production in engineered microbial hosts represents an often cost-effective and eco-friendly way to make these valuable compounds industrially available. This review provides an overview of current strategies to employ and engineer oxygenic and anoxygenic phototrophic bacteria as alternative cell factories for sustainable terpenoid production. Besides terpenoid pathway engineering, the effects of different illumination strategies on terpenoid photoproduction are key elements in the latest studies.
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Affiliation(s)
- Oliver Klaus
- Institute of Molecular Enzyme Technology, Heinrich Heine University Düsseldorf, Forschungszentrum Jülich GmbH, 52428 Jülich, Germany
| | - Fabienne Hilgers
- Institute of Molecular Enzyme Technology, Heinrich Heine University Düsseldorf, Forschungszentrum Jülich GmbH, 52428 Jülich, Germany
| | - Andreas Nakielski
- Institute for Synthetic Microbiology, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany
| | - Dennis Hasenklever
- Institute for Synthetic Microbiology, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany
| | - Karl-Erich Jaeger
- Institute of Molecular Enzyme Technology, Heinrich Heine University Düsseldorf, Forschungszentrum Jülich GmbH, 52428 Jülich, Germany; Institute of Bio, and Geosciences IBG-1: Biotechnology, Forschungszentrum Jülich GmbH, 52428 Jülich, Germany
| | - Ilka M Axmann
- Institute for Synthetic Microbiology, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany.
| | - Thomas Drepper
- Institute of Molecular Enzyme Technology, Heinrich Heine University Düsseldorf, Forschungszentrum Jülich GmbH, 52428 Jülich, Germany.
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12
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Selão TT. Exploring cyanobacterial diversity for sustainable biotechnology. JOURNAL OF EXPERIMENTAL BOTANY 2022; 73:3057-3071. [PMID: 35467729 DOI: 10.1093/jxb/erac053] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Accepted: 04/22/2022] [Indexed: 06/14/2023]
Abstract
Cyanobacteria are an evolutionarily ancient and diverse group of microorganisms. Their genetic diversity has
allowed them to occupy and play vital roles in a wide range of ecological niches, from desert soil crusts to tropical oceans. Owing to bioprospecting efforts and the development of new platform technologies enabling their study and manipulation, our knowledge of cyanobacterial metabolism is rapidly expanding. This review explores our current understanding of the genetic and metabolic features of cyanobacteria, from the more established cyanobacterial model strains to the newly isolated/described species, particularly the fast-growing, highly productive, and genetically amenable strains, as promising chassis for renewable biotechnology. It also discusses emerging technologies for their study and manipulation, enabling researchers to harness the astounding diversity of the cyanobacterial genomic and metabolic treasure trove towards the establishment of a sustainable bioeconomy.
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Affiliation(s)
- Tiago Toscano Selão
- Department of Chemical and Environmental Engineering, University of Nottingham, University Park Campus, Nottingham NG7 2RD, UK
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13
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Recent advances in the microbial production of squalene. World J Microbiol Biotechnol 2022; 38:91. [PMID: 35426523 PMCID: PMC9010451 DOI: 10.1007/s11274-022-03273-w] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Accepted: 03/30/2022] [Indexed: 11/06/2022]
Abstract
Squalene is a triterpene hydrocarbon, a biochemical precursor for all steroids in plants and animals. It is a principal component of human surface lipids, in particular of sebum. Squalene has several applications in the food, pharmaceutical, and medical sectors. It is essentially used as a dietary supplement, vaccine adjuvant, moisturizer, cardio-protective agent, anti-tumor agent and natural antioxidant. With the increased demand for squalene along with regulations on shark-derived squalene, there is a need to find alternatives for squalene production which are low-cost as well as sustainable. Microbial platforms are being considered as a potential option to meet such challenges. Considerable progress has been made using both wild-type and engineered microbial strains for improved productivity and yields of squalene. Native strains for squalene production are usually limited by low growth rates and lesser titers. Metabolic engineering, which is a rational strain engineering tool, has enabled the development of microbial strains such as Saccharomyces cerevisiae and Yarrowia lipolytica, to overproduce the squalene in high titers. This review focuses on key strain engineering strategies involving both in-silico and in-vitro techniques. Emphasis is made on gene manipulations for improved precursor pool, enzyme modifications, cofactor regeneration, up-regulation of limiting reactions, and downregulation of competing reactions during squalene production. Process strategies and challenges related to both upstream and downstream during mass cultivation are detailed.
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Xie H, Lindblad P. Expressing 2-keto acid pathway enzymes significantly increases photosynthetic isobutanol production. Microb Cell Fact 2022; 21:17. [PMID: 35105340 PMCID: PMC8805274 DOI: 10.1186/s12934-022-01738-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Accepted: 01/03/2022] [Indexed: 11/20/2022] Open
Abstract
Background Cyanobacteria, photosynthetic microorganisms, are promising green cell factories for chemical production, including biofuels. Isobutanol, a four-carbon alcohol, is considered as a superior candidate as a biofuel for its high energy density with suitable chemical and physical characteristics. The unicellular cyanobacterium Synechocystis PCC 6803 has been successfully engineered for photosynthetic isobutanol production from CO2 and solar energy in a direct process. Results Heterologous expression of α-ketoisovalerate decarboxylase (KivdS286T) is sufficient for isobutanol synthesis via the 2-keto acid pathway in Synechocystis. With additional expression of acetolactate synthase (AlsS), acetohydroxy-acid isomeroreductase (IlvC), dihydroxy-acid dehydratase (IlvD), and alcohol dehydrogenase (Slr1192OP), the Synechocystis strain HX42, with a functional 2-keto acid pathway, showed enhanced isobutanol production reaching 98 mg L−1 in short-term screening experiments. Through modulating kivdS286T copy numbers as well as the composition of the 5′-region, a final Synechocystis strain HX47 with three copies of kivdS286T showed a significantly improved isobutanol production of 144 mg L−1, an 177% increase compared to the previously reported best producing strain under identical conditions. Conclusions This work demonstrates the feasibility to express heterologous genes with a combination of self-replicating plasmid-based system and genome-based system in Synechocystis cells. Obtained isobutanol-producing Synechocystis strains form the base for further investigation of continuous, long-term-photosynthetic isobutanol production from solar energy and carbon dioxide. Graphic abstract ![]()
Supplementary Information The online version contains supplementary material available at 10.1186/s12934-022-01738-z.
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Affiliation(s)
- Hao Xie
- Microbial Chemistry, Department of Chemistry-Ångström Laboratory, Uppsala University, Box 523, 75120, Uppsala, Sweden
| | - Peter Lindblad
- Microbial Chemistry, Department of Chemistry-Ångström Laboratory, Uppsala University, Box 523, 75120, Uppsala, Sweden.
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Yadav I, Rautela A, Kumar S. Approaches in the photosynthetic production of sustainable fuels by cyanobacteria using tools of synthetic biology. World J Microbiol Biotechnol 2021; 37:201. [PMID: 34664124 DOI: 10.1007/s11274-021-03157-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Accepted: 09/29/2021] [Indexed: 10/20/2022]
Abstract
Cyanobacteria, photosynthetic prokaryotic microorganisms having a simple genetic composition are the prospective photoautotrophic cell factories for the production of a wide range of biofuel molecules. The simple genetic composition of cyanobacteria allows effortless genetic manipulation which leads to increased research endeavors from the synthetic biology approach. Various unicellular model cyanobacterial strains like Synechocystis sp. PCC 6803 and Synechococcus elongatus PCC 7942 have been successfully engineered for biofuels generation. Improved development of synthetic biology tools, genetic modification methods and advancement in transformation techniques to construct a strain that can contain multiple foreign genes in a single operon have vastly expanded the functions that can be used for engineering photosynthetic cyanobacteria for the generation of various biofuel molecules. In this review, recent advancements and approaches in synthetic biology tools used for cyanobacterial genome editing have been discussed. Apart from this, cyanobacterial productions of various fuel molecules like isoprene, limonene, α-farnesene, squalene, alkanes, butanol, and fatty acids, which can be a substitute for petroleum and fossil fuels in the future, have been elaborated.
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Affiliation(s)
- Indrajeet Yadav
- School of Biochemical Engineering, IIT (BHU) Varanasi, Varanasi, Uttar Pradesh, 221005, India
| | - Akhil Rautela
- School of Biochemical Engineering, IIT (BHU) Varanasi, Varanasi, Uttar Pradesh, 221005, India
| | - Sanjay Kumar
- School of Biochemical Engineering, IIT (BHU) Varanasi, Varanasi, Uttar Pradesh, 221005, India.
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Heath RS, Ruscoe RE, Turner NJ. The beauty of biocatalysis: sustainable synthesis of ingredients in cosmetics. Nat Prod Rep 2021; 39:335-388. [PMID: 34879125 DOI: 10.1039/d1np00027f] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Covering: 2015 up to July 2021The market for cosmetics is consumer driven and the desire for green, sustainable and natural ingredients is increasing. The use of isolated enzymes and whole-cell organisms to synthesise these products is congruent with these values, especially when combined with the use of renewable, recyclable or waste feedstocks. The literature of biocatalysis for the synthesis of ingredients in cosmetics in the past five years is herein reviewed.
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Affiliation(s)
- Rachel S Heath
- Manchester Institute of Biotechnology, Department of Chemistry, University of Manchester, 131 Princess Street, Manchester, M1 7DN, UK.
| | - Rebecca E Ruscoe
- Manchester Institute of Biotechnology, Department of Chemistry, University of Manchester, 131 Princess Street, Manchester, M1 7DN, UK.
| | - Nicholas J Turner
- Manchester Institute of Biotechnology, Department of Chemistry, University of Manchester, 131 Princess Street, Manchester, M1 7DN, UK.
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17
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Recent advances in biotechnology for marine enzymes and molecules. Curr Opin Biotechnol 2021; 69:308-315. [PMID: 34116375 DOI: 10.1016/j.copbio.2021.05.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Revised: 05/27/2021] [Accepted: 05/31/2021] [Indexed: 12/21/2022]
Abstract
The marine environment is the most biologically and chemically diverse habitat on Earth, and provides numerous marine-derived products, including enzymes and molecules, for industrial and pharmaceutical applications. Marine biotechnology provides important biological resources from marine habitat conservation to applied science. In recent years, advances in techniques in interdisciplinary research fields, including metabolic engineering and synthetic biology have significantly improved the production of marine-derived commodities. In this review, we outline the recent progress in the use or marine enzymes and molecules in biotechnology, including newly discovered products, function optimization of enzymes, and production improvement of small molecules.
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Zhang X, Betterle N, Hidalgo Martinez D, Melis A. Recombinant Protein Stability in Cyanobacteria. ACS Synth Biol 2021; 10:810-825. [PMID: 33684287 DOI: 10.1021/acssynbio.0c00610] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The living cell possesses extraordinary molecular and biochemical mechanisms by which to recognize and efficiently remove foreign, damaged, or denatured proteins. This essential function has been a barrier to the overexpression of recombinant proteins in most expression systems. A notable exception is the overexpression in E. coli of recombinant proteins, most of which, however, end-up as "inclusion bodies", i.e., cytoplasmic aggregates of proteins that are inaccessible to the cell's proteasome. "Fusion constructs as protein overexpression vectors" proved to be unparalleled in their ability to cause substantial accumulation of recombinant proteins from plants, animals, and bacteria, as soluble proteins in unicellular cyanobacteria. Recombinant protein levels in the range of 10-20% of the total cellular protein can be achieved. The present work investigated this unique property in the context of recombinant protein stability in Synechocystis sp. PCC 6803 by developing and applying an in vivo cellular tobacco etch virus cleavage system with the objective of separating the target heterologous proteins from their fusion leader sequences. The work provides new insights about the overexpression, cellular stability, and exploitation of transgenes with commercial interest, highly expressed in a cyanobacterial biofactory. The results support the notion that eukaryotic plant- and animal-origin recombinant proteins are unstable, when free in the cyanobacterial cytosol but stable when in a fusion configuration with a highly expressed cyanobacterial native or heterologous protein. Included in this analysis are recombinant proteins of the plant isoprenoid biosynthetic pathway (isoprene synthase, β-phellandrene synthase, geranyl diphosphate synthase), the human interferon protein, as well as prokaryotic proteins (tetanus toxin fragment C and the antibiotic resistance genes kanamycin and chloramphenicol). The future success of synthetic biology approaches with cyanobacteria and other systems would require overexpression of pathway enzymes to attain product volume, and the work reported in this paper sets the foundation for such recombinant pathway enzyme overexpression.
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Affiliation(s)
- Xianan Zhang
- Department of Plant and Microbial Biology, University of California, Berkeley, California 94720-3102, United States
| | - Nico Betterle
- Department of Plant and Microbial Biology, University of California, Berkeley, California 94720-3102, United States
| | - Diego Hidalgo Martinez
- Department of Plant and Microbial Biology, University of California, Berkeley, California 94720-3102, United States
| | - Anastasios Melis
- Department of Plant and Microbial Biology, University of California, Berkeley, California 94720-3102, United States
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Shukla V, Phulara SC. Impact of culture condition modulation on the high-yield, high-specificity and cost-effective production of terpenoids from microbial sources: A review. Appl Environ Microbiol 2021; 87:AEM.02369-20. [PMID: 33257314 PMCID: PMC7851692 DOI: 10.1128/aem.02369-20] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Recent years have seen a remarkable increase in the non-natural production of terpenoids from microbial route. This is due to the advancements in synthetic biology tools and techniques, which have overcome the challenges associated with the non-native production of terpenoids from microbial hosts. Although, microbes in their native form have ability to grow in wide range of physicochemical parameters such as, pH, temperature, agitation, aeration etc; however, after genetic modifications, culture conditions need to be optimized in order to achieve improved titers of desired terpenoids from engineered microbes. The physicochemical parameters together with medium supplements, such as, inducer, carbon and nitrogen source, and cofactor supply not only play an important role in high-yield production of target terpenoids from engineered host, but also reduce the accumulation of undesired metabolites in fermentation medium, thus facilitate product recovery. Further, for the economic production of terpenoids, the biomass derived sugars can be utilized together with the optimized culture conditions. In the present mini-review, we have highlighted the impact of culture conditions modulation on the high-yield and high-specificity production of terpenoids from engineered microbes. Lastly, utilization of economic feedstock has also been discussed for the cost-effective and sustainable production of terpenoids.
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Affiliation(s)
- Vibha Shukla
- Food, Drug and Chemical Toxicology Group, CSIR-Indian Institute of Toxicology Research, Vishvigyan Bhawan, 31 Mahatma Gandhi Marg, Lucknow-226001, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad-201002, India
| | - Suresh Chandra Phulara
- Department of Biotechnology, Koneru Lakshmaiah Education Foundation, Vaddeswaram, Guntur-522502, Andhra Pradesh, India
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20
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Improvement of Photoautotrophic Algal Biomass Production after Interrupted CO2 Supply by Urea and KH2PO4 Injection. ENERGIES 2021. [DOI: 10.3390/en14030778] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Microalgae-derived biomass is currently considered a sustainable feedstock for making biofuels, including biodiesel and direct combustion fuel. The photoautotrophic cultivation of microalgae using flue gas from power plants has been continuously investigated to improve the economic feasibility of microalgae processes. The utilization of waste CO2 from power plants is advantageous in reducing carbon footprints and the cost of carbon sources. Nonetheless, the sudden interruption of CO2 supply during microalgal cultivation leads to a severe reduction in biomass productivity. Herein, chemical fertilizers including urea and KH2PO4 were added to the culture medium when CO2 supply was halted. Urea (5 mM) and KH2PO4 (5 mM) were present in the culture medium in the form of CO2/NH4+ and K+/H2PO4−, respectively, preventing cell growth inhibition. The culture with urea and KH2PO4 supplementation exhibited 10.02-fold higher and 7.28-fold higher biomass and lipid productivity, respectively, compared to the culture with ambient CO2 supply due to the maintenance of a stable pH and dissolved inorganic carbon in the medium. In the mass cultivation of microalgae using flue gas from coal-fired power plants, urea and KH2PO4 were supplied while the flue gas supply was shut off. Consequently, the microalgae were grown successfully without cell death.
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21
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Stephens S, Mahadevan R, Allen DG. Engineering Photosynthetic Bioprocesses for Sustainable Chemical Production: A Review. Front Bioeng Biotechnol 2021; 8:610723. [PMID: 33490053 PMCID: PMC7820810 DOI: 10.3389/fbioe.2020.610723] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2020] [Accepted: 12/01/2020] [Indexed: 11/13/2022] Open
Abstract
Microbial production of chemicals using renewable feedstocks such as glucose has emerged as a green alternative to conventional chemical production processes that rely primarily on petroleum-based feedstocks. The carbon footprint of such processes can further be reduced by using engineered cells that harness solar energy to consume feedstocks traditionally considered to be wastes as their carbon sources. Photosynthetic bacteria utilize sophisticated photosystems to capture the energy from photons to generate reduction potential with such rapidity and abundance that cells often cannot use it fast enough and much of it is lost as heat and light. Engineering photosynthetic organisms could enable us to take advantage of this energy surplus by redirecting it toward the synthesis of commercially important products such as biofuels, bioplastics, commodity chemicals, and terpenoids. In this work, we review photosynthetic pathways in aerobic and anaerobic bacteria to better understand how these organisms have naturally evolved to harness solar energy. We also discuss more recent attempts at engineering both the photosystems and downstream reactions that transfer reducing power to improve target chemical production. Further, we discuss different methods for the optimization of photosynthetic bioprocess including the immobilization of cells and the optimization of light delivery. We anticipate this review will serve as an important resource for future efforts to engineer and harness photosynthetic bacteria for chemical production.
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Affiliation(s)
- Sheida Stephens
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON, Canada
| | - Radhakrishnan Mahadevan
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON, Canada.,Institute of Biomedical Engineering, University of Toronto, Toronto, ON, Canada
| | - D Grant Allen
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON, Canada
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22
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Jeong Y, Cho SH, Lee H, Choi HK, Kim DM, Lee CG, Cho S, Cho BK. Current Status and Future Strategies to Increase Secondary Metabolite Production from Cyanobacteria. Microorganisms 2020; 8:E1849. [PMID: 33255283 PMCID: PMC7761380 DOI: 10.3390/microorganisms8121849] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 11/15/2020] [Accepted: 11/23/2020] [Indexed: 12/16/2022] Open
Abstract
Cyanobacteria, given their ability to produce various secondary metabolites utilizing solar energy and carbon dioxide, are a potential platform for sustainable production of biochemicals. Until now, conventional metabolic engineering approaches have been applied to various cyanobacterial species for enhanced production of industrially valued compounds, including secondary metabolites and non-natural biochemicals. However, the shortage of understanding of cyanobacterial metabolic and regulatory networks for atmospheric carbon fixation to biochemical production and the lack of available engineering tools limit the potential of cyanobacteria for industrial applications. Recently, to overcome the limitations, synthetic biology tools and systems biology approaches such as genome-scale modeling based on diverse omics data have been applied to cyanobacteria. This review covers the synthetic and systems biology approaches for advanced metabolic engineering of cyanobacteria.
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Affiliation(s)
- Yujin Jeong
- Department of Biological Sciences and KAIST Institutes for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon 34141, Korea; (Y.J.); (S.-H.C.)
| | - Sang-Hyeok Cho
- Department of Biological Sciences and KAIST Institutes for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon 34141, Korea; (Y.J.); (S.-H.C.)
| | - Hookeun Lee
- Institute of Pharmaceutical Research, College of Pharmacy, Gachon University, Incheon 21999, Korea;
| | | | - Dong-Myung Kim
- Department of Chemical Engineering and Applied Chemistry, Chungnam National University, Daejeon 34134, Korea;
| | - Choul-Gyun Lee
- Department of Biological Engineering, Inha University, Incheon 22212, Korea;
| | - Suhyung Cho
- Department of Biological Sciences and KAIST Institutes for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon 34141, Korea; (Y.J.); (S.-H.C.)
| | - Byung-Kwan Cho
- Department of Biological Sciences and KAIST Institutes for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon 34141, Korea; (Y.J.); (S.-H.C.)
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23
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Metabolic Engineering and Synthetic Biology of Cyanobacteria for Carbon Capture and Utilization. BIOTECHNOL BIOPROC E 2020. [DOI: 10.1007/s12257-019-0447-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Choi SY, Woo HM. CRISPRi-dCas12a: A dCas12a-Mediated CRISPR Interference for Repression of Multiple Genes and Metabolic Engineering in Cyanobacteria. ACS Synth Biol 2020; 9:2351-2361. [PMID: 32379967 DOI: 10.1021/acssynbio.0c00091] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
In cyanobacteria, metabolic engineering using synthetic biology tools is limited to build a biosolar cell factory that converts CO2 to value-added chemicals, as repression of essential genes has not been achieved. In this study, we developed a dCas12a-mediated CRISPR interference system (CRISPRi-dCas12a) in cyanobacteria that effectively blocked the transcriptional initiation by means of a CRISPR-RNA (crRNA) and 19-nt direct repeat, resulting in 53-94% gene repression. The repression of multiple genes in a single crRNA array was also successfully achieved without a loss in repression strength. In addition, as a demonstration of the dCas12a-mediated CRISPRi for metabolic engineering, photosynthetic squalene production was improved by repressing the essential genes of either acnB encoding for aconitase or cpcB2 encoding for phycocyanin β-subunit in Synechococcus elongatus PCC 7942. The ability to regulate gene repression will promote the construction of biosolar cell factories to produce value-added chemicals.
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Affiliation(s)
- Sun Young Choi
- Department of Food Science and Biotechnology, Sungkyunkwan University (SKKU), 2066 Seobu-ro, Jangan-gu, Suwon 16419, Republic of Korea
- BioFoundry Research Center, Institute of Biotechnology and Bioengineering, Sungkyunkwan University (SKKU), 2066 Seobu-ro, Jangan-gu, Suwon 16419, Republic of Korea
| | - Han Min Woo
- Department of Food Science and Biotechnology, Sungkyunkwan University (SKKU), 2066 Seobu-ro, Jangan-gu, Suwon 16419, Republic of Korea
- BioFoundry Research Center, Institute of Biotechnology and Bioengineering, Sungkyunkwan University (SKKU), 2066 Seobu-ro, Jangan-gu, Suwon 16419, Republic of Korea
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25
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Choi SY, Sim SJ, Ko SC, Son J, Lee JS, Lee HJ, Chang WS, Woo HM. Scalable Cultivation of Engineered Cyanobacteria for Squalene Production from Industrial Flue Gas in a Closed Photobioreactor. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2020; 68:10050-10055. [PMID: 32851842 DOI: 10.1021/acs.jafc.0c03133] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Economically feasible photosynthetic cultivation of microalgal and cyanobacterial strains is crucial for the biological conversion of CO2 and potential CO2 mitigation to challenge global warming. To overcome the economic barriers, the production of value-added chemicals was desired by compensating for the overall processing cost. Here, we engineered cyanobacteria for photosynthetic squalene production and cultivated them in a scalable photobioreactor using industrial flue gas. First, an inducer-free gene expression system was developed for the cyanobacteria to lower production const. Then, the recombinant cyanobacteria were cultivated in a closed photobioreactor (100 L) using flue gas (5% CO2) as the sole carbon source under natural sunlight as the only energy source. Seasonal light intensities and temperatures were analyzed along with cyanobacterial cell growth and squalene production in August and October 2019. As a result, the effective irradiation hours were the most critical factor for the large-scale cultivation of cyanobacteria. Thus, an automated photobioprocess system will be developed based on the regional light sources.
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Affiliation(s)
- Sun Young Choi
- Department of Food Science and Biotechnology, Sungkyunkwan University (SKKU), 2066 Seobu-ro, Jangan-gu, Suwon 16419, Republic of Korea
- BioFoundry Research Center, Institute of Biotechnology and Bioengineering, Sungkyunkwan University (SKKU), 2066 Seobu-ro, Jangan-gu, Suwon 16419, Republic of Korea
| | - Sang Jun Sim
- Department of Chemical and Biological Engineering, Korea University, Seoul 02841, South Korea
| | - Sung Cheon Ko
- Department of Food Science and Biotechnology, Sungkyunkwan University (SKKU), 2066 Seobu-ro, Jangan-gu, Suwon 16419, Republic of Korea
| | - Jigyeong Son
- Department of Food Science and Biotechnology, Sungkyunkwan University (SKKU), 2066 Seobu-ro, Jangan-gu, Suwon 16419, Republic of Korea
| | - Jeong Seop Lee
- Department of Chemical and Biological Engineering, Korea University, Seoul 02841, South Korea
| | - Hyun Jeong Lee
- Department of Food Science and Biotechnology, Sungkyunkwan University (SKKU), 2066 Seobu-ro, Jangan-gu, Suwon 16419, Republic of Korea
- BioFoundry Research Center, Institute of Biotechnology and Bioengineering, Sungkyunkwan University (SKKU), 2066 Seobu-ro, Jangan-gu, Suwon 16419, Republic of Korea
| | - Won Seok Chang
- Research Institute, Korea District Heating Corporation, 186 Bundang-dong, Bundang-gu, Seongnam-si 13585, Gyeonggi-do, South Korea
| | - Han Min Woo
- Department of Food Science and Biotechnology, Sungkyunkwan University (SKKU), 2066 Seobu-ro, Jangan-gu, Suwon 16419, Republic of Korea
- BioFoundry Research Center, Institute of Biotechnology and Bioengineering, Sungkyunkwan University (SKKU), 2066 Seobu-ro, Jangan-gu, Suwon 16419, Republic of Korea
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Introduction of a green algal squalene synthase enhances squalene accumulation in a strain of Synechocystis sp. PCC 6803. Metab Eng Commun 2020; 10:e00125. [PMID: 32123662 PMCID: PMC7038009 DOI: 10.1016/j.mec.2020.e00125] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2019] [Revised: 12/28/2019] [Accepted: 02/03/2020] [Indexed: 11/21/2022] Open
Abstract
Squalene is a triterpene which is produced as a precursor for a wide range of terpenoid compounds in many organisms. It has commercial use in food and cosmetics but could also be used as a feedstock for production of chemicals and fuels, if generated sustainably on a large scale. We have engineered a cyanobacterium, Synechocystis sp. PCC 6803, for production of squalene from CO2. In this organism, squalene is produced via the methylerythritol-phosphate (MEP) pathway for terpenoid biosynthesis, and consumed by the enzyme squalene hopene cyclase (Shc) for generation of hopanoids. The gene encoding Shc in Synechocystis was inactivated (Δshc) by insertion of a gene encoding a squalene synthase from the green alga Botryococcus braunii, under control of an inducible promoter. We could demonstrate elevated squalene generation in cells where the algal enzyme was induced. Heterologous overexpression of genes upstream in the MEP pathway further enhanced the production of squalene, to a level three times higher than the Δshc background strain. During growth in flat panel bioreactors, a squalene titer of 5.1 mg/L of culture was reached.
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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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Pattharaprachayakul N, Lee HJ, Incharoensakdi A, Woo HM. Evolutionary Engineering of Cyanobacteria to Enhance the Production of α-Farnesene from CO 2. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2019; 67:13658-13664. [PMID: 31755253 DOI: 10.1021/acs.jafc.9b06254] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Photosynthetic cyanobacteria can fix CO2 and utilize it as the sole carbon source for cell growth and production of biochemicals. Here, we metabolically engineered Synechococcus elongatus PCC 7942 for an enhanced production of α-farnesene by optimizing the ribosome-binding site (RBS) of the codon-optimized farnesene synthase gene. The production of α-farnesene was found to be enhanced in strains with a low translation initiation rate, resulting in α-farnesene production (0.57 mg/(L day)). Using the RBS variants and random mutations, we performed fluorescence-based analysis of cells grown in 96-well culture plates to screen the α-farnesene-producing strains but could not improve the titers of the RBS-optimized strains. However, evolutionary engineering of the RBS-optimized strains resulted in a twofold increase in α-farnesene production (1.2 mg/(L day)) compared to the previous study. Therefore, combining metabolic and evolutionary engineering might be helpful for enhancing the cellular fitness of cyanobacteria for the production of target chemicals.
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Affiliation(s)
- Napisa Pattharaprachayakul
- Department of Food Science and Biotechnology , Sungkyunkwan University (SKKU) , 2066 Seobu-ro , Jangan-gu, Suwon 16419 , Republic of Korea
- Laboratory of Cyanobacterial Biotechnology, Department of Biochemistry, Faculty of Science , Chulalongkorn University , 254 Phayathai Road , Pathumwan, Bangkok 10330 , Thailand
| | - Hyun Jeong Lee
- Department of Food Science and Biotechnology , Sungkyunkwan University (SKKU) , 2066 Seobu-ro , Jangan-gu, Suwon 16419 , Republic of Korea
| | - Aran Incharoensakdi
- Laboratory of Cyanobacterial Biotechnology, Department of Biochemistry, Faculty of Science , Chulalongkorn University , 254 Phayathai Road , Pathumwan, Bangkok 10330 , Thailand
| | - Han Min Woo
- Department of Food Science and Biotechnology , Sungkyunkwan University (SKKU) , 2066 Seobu-ro , Jangan-gu, Suwon 16419 , Republic of Korea
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29
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Sung YJ, Patel AK, Yu BS, Choi HI, Kim J, Jin E, Sim SJ. Sedimentation rate-based screening of oleaginous microalgae for utilization as a direct combustion fuel. BIORESOURCE TECHNOLOGY 2019; 293:122045. [PMID: 31470230 DOI: 10.1016/j.biortech.2019.122045] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Revised: 08/17/2019] [Accepted: 08/20/2019] [Indexed: 06/10/2023]
Abstract
The co-combustion of microalgae biomass with coal has the potential to significantly reduce CO2 emissions by eliminating expensive and carbon-emitting downstream processes. In this study, the utilization of microalgal biomass as a direct combustion fuel in co-firing industries and the screening of potential oleaginous strains of high calorific value was investigated. High-lipid accumulating mutants were selected from mutant mixtures based on cell density using differential sedimentation rates. Of the mutant strains obtained in the top phase of the separation medium, 72% showed a higher lipid content than the wild-type strain. One mutant strain exhibited a 57.3% enhanced lipid content and a 9.3% lower heating value (LHV), both indicators of direct combustion fuel performance, compared to the wild-type strain. Our findings indicate that sedimentation rate-based strain selection allows for the easy and rapid screening of high-lipid content algal strains for the use of microalgae as direct combustion fuels.
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Affiliation(s)
- Young Joon Sung
- Department of Chemical and Biological Engineering, Korea University, 145, Anam-ro, Seongbuk-gu, Seoul 02841, Republic of Korea
| | - Anil Kumar Patel
- Department of Chemical and Biological Engineering, Korea University, 145, Anam-ro, Seongbuk-gu, Seoul 02841, Republic of Korea
| | - Byung Sun Yu
- Department of Chemical and Biological Engineering, Korea University, 145, Anam-ro, Seongbuk-gu, Seoul 02841, Republic of Korea
| | - Hong Il Choi
- Department of Chemical and Biological Engineering, Korea University, 145, Anam-ro, Seongbuk-gu, Seoul 02841, Republic of Korea
| | - Jongrae Kim
- Department of Life Science, College of Natural Sciences, Hanyang University, Seoul 04763, Republic of Korea
| | - EonSeon Jin
- Department of Life Science, College of Natural Sciences, Hanyang University, Seoul 04763, Republic of Korea
| | - Sang Jun Sim
- Department of Chemical and Biological Engineering, Korea University, 145, Anam-ro, Seongbuk-gu, Seoul 02841, Republic of Korea.
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Paramasivan K, Kumar HN P, Mutturi S. Systems-based Saccharomyces cerevisiae strain design for improved squalene synthesis. Biochem Eng J 2019. [DOI: 10.1016/j.bej.2019.04.025] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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31
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Burkart MD, Hazari N, Tway CL, Zeitler EL. Opportunities and Challenges for Catalysis in Carbon Dioxide Utilization. ACS Catal 2019. [DOI: 10.1021/acscatal.9b02113] [Citation(s) in RCA: 179] [Impact Index Per Article: 35.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Michael D. Burkart
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093-0358, United States
| | - Nilay Hazari
- Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, United States
| | - Cathy L. Tway
- Johnson Matthey, 2 Trans Am Plaza Drive, Suite 230, Oakbrook Terrace, Illinois 60181, United States
| | - Elizabeth L. Zeitler
- Board on Energy
and Environmental Systems, National Academies of Sciences, Engineering and Medicine, 500 Fifth Street, NW, Washington, D.C. 20001, United States
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32
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Khan AZ, Bilal M, Mehmood S, Sharma A, Iqbal HMN. State-of-the-Art Genetic Modalities to Engineer Cyanobacteria for Sustainable Biosynthesis of Biofuel and Fine-Chemicals to Meet Bio-Economy Challenges. Life (Basel) 2019; 9:life9030054. [PMID: 31252652 PMCID: PMC6789541 DOI: 10.3390/life9030054] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2019] [Revised: 06/15/2019] [Accepted: 06/26/2019] [Indexed: 02/07/2023] Open
Abstract
In recent years, metabolic engineering of microorganisms has attained much research interest to produce biofuels and industrially pertinent chemicals. Owing to the relatively fast growth rate, genetic malleability, and carbon neutral production process, cyanobacteria has been recognized as a specialized microorganism with a significant biotechnological perspective. Metabolically engineering cyanobacterial strains have shown great potential for the photosynthetic production of an array of valuable native or non-native chemicals and metabolites with profound agricultural and pharmaceutical significance using CO2 as a building block. In recent years, substantial improvements in developing and introducing novel and efficient genetic tools such as genome-scale modeling, high throughput omics analyses, synthetic/system biology tools, metabolic flux analysis and clustered regularly interspaced short palindromic repeats (CRISPR)-associated nuclease (CRISPR/cas) systems have been made for engineering cyanobacterial strains. Use of these tools and technologies has led to a greater understanding of the host metabolism, as well as endogenous and heterologous carbon regulation mechanisms which consequently results in the expansion of maximum productive ability and biochemical diversity. This review summarizes recent advances in engineering cyanobacteria to produce biofuel and industrially relevant fine chemicals of high interest. Moreover, the development and applications of cutting-edge toolboxes such as the CRISPR-cas9 system, synthetic biology, high-throughput "omics", and metabolic flux analysis to engineer cyanobacteria for large-scale cultivation are also discussed.
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Affiliation(s)
- Aqib Zafar Khan
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Muhammad Bilal
- School of Life Science and Food Engineering, Huaiyin Institute of Technology, Huaian 223003, China.
| | - Shahid Mehmood
- Bio-X Institute, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders (Ministry of Education), Shanghai Jiao Tong University, Shanghai 200030, China
| | - Ashutosh Sharma
- Tecnologico de Monterrey, School of Engineering and Sciences, Campus Queretaro, Epigmenio Gonzalez 500, Queretaro CP 76130, Mexico
| | - Hafiz M N Iqbal
- Tecnologico de Monterrey, School of Engineering and Sciences, Campus Monterrey, Ave. Eugenio Garza Sada 2501, Monterrey CP 64849, N.L., Mexico.
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Gohil N, Bhattacharjee G, Khambhati K, Braddick D, Singh V. Corrigendum: Engineering Strategies in Microorganisms for the Enhanced Production of Squalene: Advances, Challenges and Opportunities. Front Bioeng Biotechnol 2019; 7:114. [PMID: 31192199 PMCID: PMC6547300 DOI: 10.3389/fbioe.2019.00114] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Accepted: 05/07/2019] [Indexed: 01/05/2023] Open
Abstract
[This corrects the article DOI: 10.3389/fbioe.2019.00050.].
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Affiliation(s)
- Nisarg Gohil
- School of Biological Sciences and Biotechnology, Institute of Advanced Research, Koba Institutional Area, Gandhinagar, India
| | - Gargi Bhattacharjee
- School of Biological Sciences and Biotechnology, Institute of Advanced Research, Koba Institutional Area, Gandhinagar, India
| | - Khushal Khambhati
- School of Biological Sciences and Biotechnology, Institute of Advanced Research, Koba Institutional Area, Gandhinagar, India
| | - Darren Braddick
- Department of R&D, Cementic S. A. S., Genopole, Paris, France
| | - Vijai Singh
- School of Biological Sciences and Biotechnology, Institute of Advanced Research, Koba Institutional Area, Gandhinagar, India
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34
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Xia P, Ling H, Foo JL, Chang MW. Synthetic Biology Toolkits for Metabolic Engineering of Cyanobacteria. Biotechnol J 2019; 14:e1800496. [DOI: 10.1002/biot.201800496] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Revised: 02/19/2019] [Indexed: 12/20/2022]
Affiliation(s)
- Peng‐Fei Xia
- Department of Biochemistry Yong Loo Lin School of MedicineNational University of Singapore8 Medical Drive Singapore 117597 Singapore
- NUS Synthetic Biology for Clinical and Technological Innovation (SynCTI)National University of Singapore28 Medical Drive Singapore 117456 Singapore
| | - Hua Ling
- Department of Biochemistry Yong Loo Lin School of MedicineNational University of Singapore8 Medical Drive Singapore 117597 Singapore
- NUS Synthetic Biology for Clinical and Technological Innovation (SynCTI)National University of Singapore28 Medical Drive Singapore 117456 Singapore
| | - Jee Loon Foo
- Department of Biochemistry Yong Loo Lin School of MedicineNational University of Singapore8 Medical Drive Singapore 117597 Singapore
- NUS Synthetic Biology for Clinical and Technological Innovation (SynCTI)National University of Singapore28 Medical Drive Singapore 117456 Singapore
| | - Matthew Wook Chang
- Department of Biochemistry Yong Loo Lin School of MedicineNational University of Singapore8 Medical Drive Singapore 117597 Singapore
- NUS Synthetic Biology for Clinical and Technological Innovation (SynCTI)National University of Singapore28 Medical Drive Singapore 117456 Singapore
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35
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Selão TT, Włodarczyk A, Nixon PJ, Norling B. Growth and selection of the cyanobacterium Synechococcus sp. PCC 7002 using alternative nitrogen and phosphorus sources. Metab Eng 2019; 54:255-263. [PMID: 31063791 DOI: 10.1016/j.ymben.2019.04.013] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Revised: 04/08/2019] [Accepted: 04/29/2019] [Indexed: 12/14/2022]
Abstract
Cyanobacteria, such as Synechococcus sp. PCC 7002 (Syn7002), are promising chassis strains for "green" biotechnological applications as they can be grown in seawater using oxygenic photosynthesis to fix carbon dioxide into biomass. Their other major nutritional requirements for efficient growth are sources of nitrogen (N) and phosphorus (P). As these organisms are more economically cultivated in outdoor open systems, there is a need to develop cost-effective approaches to prevent the growth of contaminating organisms, especially as the use of antibiotic selection markers is neither economically feasible nor ecologically desirable due to the risk of horizontal gene transfer. Here we have introduced a synthetic melamine degradation pathway into Syn7002 and evolved the resulting strain to efficiently use the nitrogen-rich xenobiotic compound melamine as the sole N source. We also show that expression of phosphite dehydrogenase in the absence of its cognate phosphite transporter permits growth of Syn7002 on phosphite and can be used as a selectable marker in Syn7002. We combined these two strategies to generate a strain that can grow on melamine and phosphite as sole N and P sources, respectively. This strain is able to resist deliberate contamination in large excess and should be a useful chassis for metabolic engineering and biotechnological applications using cyanobacteria.
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Affiliation(s)
| | - Artur Włodarczyk
- School of Biological Sciences, Nanyang Technological University, Singapore
| | - Peter J Nixon
- School of Biological Sciences, Nanyang Technological University, Singapore; Sir Ernst Chain Building- Wolfson Laboratories, Department of Life Sciences, Imperial College London, S. Kensington Campus, London, SW7 2AZ, UK
| | - Birgitta Norling
- School of Biological Sciences, Nanyang Technological University, Singapore.
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36
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Gohil N, Bhattacharjee G, Khambhati K, Braddick D, Singh V. Engineering Strategies in Microorganisms for the Enhanced Production of Squalene: Advances, Challenges and Opportunities. Front Bioeng Biotechnol 2019; 7:50. [PMID: 30968019 PMCID: PMC6439483 DOI: 10.3389/fbioe.2019.00050] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Accepted: 03/01/2019] [Indexed: 12/20/2022] Open
Abstract
The triterpene squalene is a natural compound that has demonstrated an extraordinary diversity of uses in pharmaceutical, nutraceutical, and personal care industries. Emboldened by this range of uses, novel applications that can gain profit from the benefits of squalene as an additive or supplement are expanding, resulting in its increasing demand. Ever since its discovery, the primary source has been the deep-sea shark liver, although recent declines in their populations and justified animal conservation and protection regulations have encouraged researchers to identify a novel route for squalene biosynthesis. This renewed scientific interest has profited from immense developments in synthetic biology, which now allows fine-tuning of a wider range of plants, fungi, and microorganisms for improved squalene production. There are numerous naturally squalene producing species and strains; although they generally do not make commercially viable yields as primary shark liver sources can deliver. The recent advances made toward improving squalene output from natural and engineered species have inspired this review. Accordingly, it will cover in-depth knowledge offered by the studies of the natural sources, and various engineering-based strategies that have been used to drive the improvements in the pathways toward large-scale production. The wide uses of squalene are also discussed, including the notable developments in anti-cancer applications and in augmenting influenza vaccines for greater efficacy.
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Affiliation(s)
- Nisarg Gohil
- School of Biological Sciences and Biotechnology, Institute of Advanced Research, Koba Institutional Area, Gandhinagar, India
| | - Gargi Bhattacharjee
- School of Biological Sciences and Biotechnology, Institute of Advanced Research, Koba Institutional Area, Gandhinagar, India
| | - Khushal Khambhati
- School of Biological Sciences and Biotechnology, Institute of Advanced Research, Koba Institutional Area, Gandhinagar, India
| | - Darren Braddick
- Department of R&D, Cementic S. A. S., Genopole, Paris, France
| | - Vijai Singh
- School of Biological Sciences and Biotechnology, Institute of Advanced Research, Koba Institutional Area, Gandhinagar, India
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37
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Choi HI, Lee JS, Choi JW, Shin YS, Sung YJ, Hong ME, Kwak HS, Kim CY, Sim SJ. Performance and potential appraisal of various microalgae as direct combustion fuel. BIORESOURCE TECHNOLOGY 2019; 273:341-349. [PMID: 30448687 DOI: 10.1016/j.biortech.2018.11.030] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Revised: 11/05/2018] [Accepted: 11/08/2018] [Indexed: 06/09/2023]
Abstract
Direct combustion of biomass is considered the most effective and simple means to contribute to CO2 reduction. In this context, the life-cycle potential of microalgal solid fuel, which has been overlooked so far, was comprehensively scrutinized ranging from cultivation to direct combustion. According to the quantitative data, using the raw fuel was confirmed to offer great benefits over the conventional lipid-targeted microalgal fuel systems through exploiting all of the biomass' energy potential, thereby being able to significantly increase the energy yield from biomass. The solid fuel is shown to exhibit diverse positive aspects owing to its remarkable calorific value, productivity and CO2 fixation ability. The combustion test reveals coal-microalgae co-combustion brings beneficial consequences on combustibility and environmental impacts with no notable thermal efficiency drop. This holistic appraisal shows microalgae patently possess high potential as a direct combustion fuel, even outperforming that of extensively used woody fuels.
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Affiliation(s)
- Hong Il Choi
- Department of Chemical and Biological Engineering, Korea University, 145, Anam-ro, Seongbuk-gu, Seoul 02841, South Korea
| | - Jeong Seop Lee
- Department of Chemical and Biological Engineering, Korea University, 145, Anam-ro, Seongbuk-gu, Seoul 02841, South Korea
| | - Jin Won Choi
- Department of Chemical and Biological Engineering, Korea University, 145, Anam-ro, Seongbuk-gu, Seoul 02841, South Korea
| | - Ye Sol Shin
- Department of Chemical and Biological Engineering, Korea University, 145, Anam-ro, Seongbuk-gu, Seoul 02841, South Korea
| | - Young Joon Sung
- Department of Chemical and Biological Engineering, Korea University, 145, Anam-ro, Seongbuk-gu, Seoul 02841, South Korea
| | - Min Eui Hong
- Department of Chemical and Biological Engineering, Korea University, 145, Anam-ro, Seongbuk-gu, Seoul 02841, South Korea
| | - Ho Seok Kwak
- Department of Food Science and Engineering, Dongyang Mirae University, 445, Gyeongin-ro, Guro-gu, Seoul 08221, South Korea
| | - Chan Young Kim
- Korea Western Power Co., Ltd., 285, Jungang-ro, Taean-eup, Taean-gun, Chungcheongnam-do 32140, South Korea
| | - Sang Jun Sim
- Department of Chemical and Biological Engineering, Korea University, 145, Anam-ro, Seongbuk-gu, Seoul 02841, South Korea.
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38
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Park J, Yu BJ, Choi JI, Woo HM. Heterologous Production of Squalene from Glucose in Engineered Corynebacterium glutamicum Using Multiplex CRISPR Interference and High-Throughput Fermentation. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2019; 67:308-319. [PMID: 30558416 DOI: 10.1021/acs.jafc.8b05818] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The sustainable production of squalene has driven the development of microbial cell factories due to the limitation of low-yielding bioprocesses from plants and illegal harvesting shark liver. We report the metabolic engineering of Corynebacterium glutamicum to produce squalene from glucose. Combinatorial metabolic engineering strategies for precursor rebalancing, redox balancing, and blocking the competing pathway for the isopentenyl diphosphate availabilities were applied by repressing the target genes using the CRISPR interference. The best engineered strain using high-throughput fermentation produced squalene from glucose at 5.4 ± 0.3 mg/g dry cell weight (DCW) and 105.3 ± 3.0 mg/L, which was a 5.2-fold increase over the parental strain. In addition, flask cultivation of C. glutamicum overexpressing the dxs and idi genes with squalene synthase gene and repressing the idsA gene resulted in production of squalene at 5.8 ± 0.4 mg/g DCW and 82.8 ± 6.2 mg/L, which was a 3.4-fold increase over the parental strain.
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Affiliation(s)
- Jaehyun Park
- Department of Food Science and Biotechnology , Sungkyunkwan University (SKKU) , 2066 Seobu-ro , Jangan-gu, Suwon 16419 , Republic of Korea
| | - Byung Jo Yu
- Intelligent Sustainable Materials R&D Group, Research Institute of Sustainable Manufacturing System , Korea Institute of Industrial Technology , 89 Yangdaegiro-gil , Ipjang-myeon, Seobuk-gu, Cheonan 31056 , Republic of Korea
| | - Jong-Il Choi
- Department of Biotechnology and Bioengineering , Chonnam National University , 77 Yongbong-ro , Buk-gu, Gwangju 61186 , Republic of Korea
| | - Han Min Woo
- Department of Food Science and Biotechnology , Sungkyunkwan University (SKKU) , 2066 Seobu-ro , Jangan-gu, Suwon 16419 , Republic of Korea
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39
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Ko SC, Lee HJ, Choi SY, Choi JI, Woo HM. Bio-solar cell factories for photosynthetic isoprenoids production. PLANTA 2019; 249:181-193. [PMID: 30078076 DOI: 10.1007/s00425-018-2969-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Accepted: 08/01/2018] [Indexed: 05/08/2023]
Abstract
Photosynthetic production of isoprenoids in cyanobacteria is considered in terms of metabolic engineering and biological importance. Metabolic engineering of photosynthetic bacteria (cyanobacteria) has been performed to construct bio-solar cell factories that convert carbon dioxide to various value-added chemicals. Isoprenoids, which are found in nature and range from essential cell components to defensive molecules, have great value in cosmetics, pharmaceutics, and biofuels. In this review, we summarize the recent engineering of cyanobacteria for photosynthetic isoprenoids production as well as carbon molar basis comparisons with heterotrophic isoprenoids production in engineered Escherichia coli.
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Affiliation(s)
- Sung Cheon Ko
- Department of Food Science and Biotechnology, Sungkyunkwan University (SKKU), 2066 Seobu-ro, Jangan-gu, Suwon, 16419, Republic of Korea
| | - Hyun Jeong Lee
- Department of Food Science and Biotechnology, Sungkyunkwan University (SKKU), 2066 Seobu-ro, Jangan-gu, Suwon, 16419, Republic of Korea
| | - Sun Young Choi
- Department of Food Science and Biotechnology, Sungkyunkwan University (SKKU), 2066 Seobu-ro, Jangan-gu, Suwon, 16419, Republic of Korea
| | - Jong-Il Choi
- Department of Biotechnology and Bioengineering, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju, 61186, Republic of Korea
| | - Han Min Woo
- Department of Food Science and Biotechnology, Sungkyunkwan University (SKKU), 2066 Seobu-ro, Jangan-gu, Suwon, 16419, Republic of Korea.
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40
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Metabolic engineering tools in model cyanobacteria. Metab Eng 2018; 50:47-56. [DOI: 10.1016/j.ymben.2018.03.014] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2018] [Revised: 03/15/2018] [Accepted: 03/15/2018] [Indexed: 12/27/2022]
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41
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Liu H, Ni J, Xu P, Tao F. Enhancing Light-Driven 1,3-Propanediol Production by Using Natural Compartmentalization of Differentiated Cells. ACS Synth Biol 2018; 7:2436-2446. [PMID: 30234972 DOI: 10.1021/acssynbio.8b00239] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Synthetic biology emerges as a powerful approach for unlocking the potential of cyanobacteria to produce various chemicals. However, the highly oxidative intracellular environment of cyanobacteria is incompatible to numerous introduced enzymes from anaerobes. In this study, we explore a strategy based on natural compartmentalization of cyanobacterial heterocysts to overcome the incompatibility. Hence, the oxygen-sensitive 1,3-propanediol (1,3-PDO) biosynthetic pathway was selected as a model and insulated in heterocysts to evaluate the proposed strategy. Thus, the genes from different sources for 1,3-PDO production were tandemly arrayed with promoter, resulting the assembled 1,3-PDO synthetic cassettes. Then the synthetic cassettes were integrated into the chromosome of Anabaena sp. strain PCC7120 by homologous recombination, respectively. The engineered strain P11 containing the genes from facultative anaerobe Klebsiella pneumoniae (cassette KP) accumulated 46.0 mg L-1 of 1,3-PDO when heterocysts were present, which is approximately 1.7-fold higher than that of no heterocysts. As for the strains (P12, P13, and P14) containing the genes from strictly anaerobic bacterium Clostridium butyricum (cassette CB), the product 1,3-PDO could only be detected when heterocysts were present. These results indicate that insulation of the oxygen-sensitive 1,3-PDO pathway with heterocysts is an effective way to protect these enzymes in cyanobacteria. The strategy may have the potential of serving as a universal strategy to overcome the incompatibility of oxygen-sensitivity in synthetic biology.
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Affiliation(s)
- Hongyu Liu
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Developmental Sciences, and School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, People’s Republic of China
| | - Jun Ni
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Developmental Sciences, and School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, People’s Republic of China
| | - Ping Xu
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Developmental Sciences, and School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, People’s Republic of China
| | - Fei Tao
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Developmental Sciences, and School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, People’s Republic of China
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42
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Franden MA, Jayakody LN, Li WJ, Wagner NJ, Cleveland NS, Michener WE, Hauer B, Blank LM, Wierckx N, Klebensberger J, Beckham GT. Engineering Pseudomonas putida KT2440 for efficient ethylene glycol utilization. Metab Eng 2018; 48:197-207. [DOI: 10.1016/j.ymben.2018.06.003] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Revised: 06/02/2018] [Accepted: 06/05/2018] [Indexed: 10/14/2022]
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43
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Choi SY, Sim SJ, Choi JI, Woo HM. Identification of small droplets of photosynthetic squalene in engineered Synechococcus elongatus PCC 7942 using TEM and selective fluorescent Nile red analysis. Lett Appl Microbiol 2018. [PMID: 29527705 DOI: 10.1111/lam.12874] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
To identify microbial squalene that has been widely used in various industrial applications, intracellular formation of photosynthetic squalene was investigated using the previously engineered Synechococcus elongatusPCC 7942 strain. Unlike the proposed localization of squalene in the membrane bilayer, small droplets were identified in the cytoplasm of S. elongatusPCC 7942 as squalene using transmission electron microscopy analysis. Determination of the diameters of the squalene droplets with manual examination of 1016 droplets in different squalene-producing strains indicated larger squalene droplets in larger cells. Based on the observation of a sole droplet of squalene in a cyanobacterium, fluorescent Nile red was used for the selective staining of squalene. The fluorescent intensities were correlated with squalene contents determined using gas chromatography-mass spectrometry. Photosynthetic squalene was identified as a small droplet in S. elongatusPCC 7942, and this noninvasive quantitative method could be useful to promote high-throughput strain development for squalene production. SIGNIFICANCE AND IMPACT OF THE STUDY Engineering of Cyanobacteria has focused on sustainable production of squalene by converting CO2 . Before improving the photosynthetic squalene production, we characterized formation of squalene, showing small droplets in the cytoplasm instead of single granule. Based on the finding and the analysis, this study has provided valuable evidences how further metabolic engineering strategies should apply to enhance the production yield.
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Affiliation(s)
- S Y Choi
- Department of Food Science and Biotechnology, Sungkyunkwan University (SKKU), Jangan-gu, Suwon, Korea.,Institute of Biotechnology and Bioengineering, Sungkyunkwan University (SKKU), Jangan-gu, Suwon, Korea
| | - S J Sim
- Department of Chemical and Biological Engineering, Korea University, Seongbuk-gu, Seoul, Korea
| | - J-I Choi
- Department of Biotechnology and Bioengineering, Chonnam National University, Buk-gu, Gwangju, Korea
| | - H M Woo
- Department of Food Science and Biotechnology, Sungkyunkwan University (SKKU), Jangan-gu, Suwon, Korea
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Ni J, Tao F, Xu P, Yang C. Engineering Cyanobacteria for Photosynthetic Production of C3 Platform Chemicals and Terpenoids from CO 2. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1080:239-259. [PMID: 30091098 DOI: 10.1007/978-981-13-0854-3_10] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Recent years have witnessed a rising demand for bioproduced chemicals owing to restricted availability of petrochemical resources and increasing environmental concerns. Extensive efforts have been invested in the metabolic engineering of microorganisms for biosynthesis of chemicals and fuels. Among these, direct conversion of CO2 to chemicals by photoautotrophic microorganism cyanobacteria represents a green route with incredibly potent. Cyanobacteria have been engineered for the production of numerous biofuels and chemicals, such as 2,3-butanediol, fatty acids, isobutyraldehyde, and n-butanol. Under the current condition, it might be initially wiser to produce chemicals with higher value or higher yield. Photosynthetic production of C3 platform chemicals could withdraw carbon close to fixation to maximize the pool of available carbon, thus achieving the strong production rates. Photosynthetic production of terpenoids is another good choice due to the higher value of these compounds. Here, we review recent advances in generating C3 chemicals and valuable terpenoids from cyanobacteria.
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Affiliation(s)
- Jun Ni
- State Key Laboratory of Microbial Metabolism, and School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, Shanghai, People's Republic of China
| | - Fei Tao
- State Key Laboratory of Microbial Metabolism, and School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, Shanghai, People's Republic of China
| | - Ping Xu
- State Key Laboratory of Microbial Metabolism, and School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, Shanghai, People's Republic of China
| | - Chen Yang
- CAS-Key Laboratory of Synthetic Biology, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China.
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Lee HJ, Lee J, Lee SM, Um Y, Kim Y, Sim SJ, Choi JI, Woo HM. Direct Conversion of CO 2 to α-Farnesene Using Metabolically Engineered Synechococcus elongatus PCC 7942. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2017; 65:10424-10428. [PMID: 29068210 DOI: 10.1021/acs.jafc.7b03625] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Direct conversion of carbon dioxide (CO2) to value-added chemicals by engineering of cyanobacteria has received attention as a sustainable strategy in food and chemical industries. Herein, Synechococcus elongatus PCC 7942, a model cyanobacterium, was engineered to produce α-farnesene from CO2. As a result of the lack of farnesene synthase (FS) activity in the wild-type cyanobacterium, we metabolically engineered S. elongatus PCC 7942 to express heterologous FS from either Norway spruce or apple fruit, resulting in detectable peaks of α-farnesene. To enhance α-farnesene production, an optimized methylerythritol phosphate (MEP) pathway was introduced in the farnesene-producing strain to supply farnesyl diphosphate. Subsequent cyanobacterial culture with a dodecane overlay resulted in photosynthetic production of α-farnesene (4.6 ± 0.4 mg/L in 7 days) from CO2. To the best of our knowledge, this is the first report of the photosynthetic production of α-farnesene from CO2 in the unicellular cyanobacterium S. elongatus PCC 7942.
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Affiliation(s)
| | - Jiwon Lee
- Clean Energy Research Center, Korea Institute of Science and Technology , Hwarang-ro 14-gil 5, Seongbuk-gu, Seoul 02792, Republic of Korea
| | - Sun-Mi Lee
- Clean Energy Research Center, Korea Institute of Science and Technology , Hwarang-ro 14-gil 5, Seongbuk-gu, Seoul 02792, Republic of Korea
| | - Youngsoon Um
- Clean Energy Research Center, Korea Institute of Science and Technology , Hwarang-ro 14-gil 5, Seongbuk-gu, Seoul 02792, Republic of Korea
| | - Yunje Kim
- Clean Energy Research Center, Korea Institute of Science and Technology , Hwarang-ro 14-gil 5, Seongbuk-gu, Seoul 02792, Republic of Korea
| | - Sang Jun Sim
- Department of Chemical and Biological Engineering, Korea University , 145 Anam-ro, Seongbuk-gu, Seoul 02841, Republic of Korea
| | - Jong-Il Choi
- Department of Biotechnology and Bioengineering, Chonnam National University , 77 Yongbong-ro, Buk-gu, Gwangju 61186, Republic of Korea
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Zhu B, Chen G, Cao X, Wei D. Molecular characterization of CO 2 sequestration and assimilation in microalgae and its biotechnological applications. BIORESOURCE TECHNOLOGY 2017; 244:1207-1215. [PMID: 28606753 DOI: 10.1016/j.biortech.2017.05.199] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Revised: 05/29/2017] [Accepted: 05/30/2017] [Indexed: 06/07/2023]
Abstract
Microalgae are renewable feedstock for sustainable biofuel production, cell factory for valuable chemicals and promising in alleviation of greenhouse gas CO2. However, the carbon assimilation capacity is still the bottleneck for higher productivity. Molecular characterization of CO2 sequestration and assimilation in microalgae has advanced in the past few years and are reviewed here. In some cyanobacteria, genes for 2-oxoglytarate dehydrogenase was replaced by four alternative mechanisms to fulfill TCA cycle. In green algae Coccomyxa subellipsoidea C-169, alternative carbon assimilation pathway was upregulated under high CO2 conditions. These advances thus provide new insights and new targets for accelerating CO2 sequestration rate and enhancing bioproduct synthesis in microalgae. When integrated with conventional parameter optimization, molecular approach for microalgae modification targeting at different levels is promising in generating value-added chemicals from green algae and cyanobacteria efficiently in the near future.
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Affiliation(s)
- Baojun Zhu
- School of Food Sciences and Engineering, South China University of Technology, Wushan Rd. 381, Guangzhou 510641, PR China
| | - Gu Chen
- School of Food Sciences and Engineering, South China University of Technology, Wushan Rd. 381, Guangzhou 510641, PR China
| | - Xupeng Cao
- Marine Bioengineering Group, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, PR China
| | - Dong Wei
- School of Food Sciences and Engineering, South China University of Technology, Wushan Rd. 381, Guangzhou 510641, PR China.
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