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Madhu S, Sengupta A, Sarnaik AP, Wangikar PP. Expanding the synthetic biology repertoire of a fast-growing cyanobacterium Synechococcus elongatus PCC 11801. Biotechnol Bioeng 2024. [PMID: 38773863 DOI: 10.1002/bit.28740] [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: 12/23/2023] [Revised: 05/04/2024] [Accepted: 05/07/2024] [Indexed: 05/24/2024]
Abstract
Synechococcus elongatus PCC 11801 is a fast-growing cyanobacterium, exhibiting high tolerance to environmental stresses. We have earlier characterized its genome and analysed its transcriptome and proteome. However, to deploy it as a potential cell factory, it is necessary to expand its synthetic biology toolbox, including promoter elements and ribosome binding sites (RBSs). Here, based on the global transcriptome analysis, 48 native promoters of the genes with high transcript count were characterized using a fluorescent reporter system. The promoters PcpcB, PpsbA1, and P11770 exhibited consistently high fluorescence under all the cultivation conditions. Similarly, from the genome data and proteome analysis, 534 operons were identified. Fifteen intergenic regions exhibiting higher protein expression from the downstream gene were systematically characterized for identifying RBSs, using an operon construct comprising fluorescent protein genes eyfp and mTurq under PcpcB (PcpcB:eyfp:RBS:mTurq:TrrnB). Overall, the work presents promoter and RBS sequence libraries, with varying strengths, to expedite bioengineering of PCC 11801.
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Affiliation(s)
- Swati Madhu
- Department of Chemical Engineering, Indian Institute of Technology Bombay, Mumbai, India
| | - Annesha Sengupta
- Department of Chemical Engineering, Indian Institute of Technology Bombay, Mumbai, India
| | - Aditya P Sarnaik
- Department of Chemical Engineering, Indian Institute of Technology Bombay, Mumbai, India
| | - Pramod P Wangikar
- Department of Chemical Engineering, Indian Institute of Technology Bombay, Mumbai, India
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2
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Treece TR, Pattanayak S, Matson MM, Cepeda MM, Berben LA, Atsumi S. Electrical-biological hybrid system for carbon efficient isobutanol production. Metab Eng 2023; 80:142-150. [PMID: 37739158 DOI: 10.1016/j.ymben.2023.09.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Revised: 09/04/2023] [Accepted: 09/14/2023] [Indexed: 09/24/2023]
Abstract
We have developed an electrical-biological hybrid system wherein an engineered microorganism consumes electrocatalytically produced formate from CO2 to supplement the bioproduction of isobutanol, a valuable fuel chemical. Biological CO2 sequestration is notoriously slow compared to electrochemical CO2 reduction, while electrochemical methods struggle to generate carbon-carbon bonds which readily form in biological systems. A hybrid system provides a promising method for combining the benefits of both biology and electrochemistry. Previously, Escherichia coli was engineered to assimilate formate and CO2 in central metabolism using the reductive glycine pathway. In this work, we have shown that chemical production in E. coli can benefit from single carbon substrates when equipped with the RGP. By installing the RGP and the isobutanol biosynthetic pathway into E. coli and by further genetic modifications, we have generated a strain of E. coli that can consume formate and produce isobutanol at a yield of >100% of theoretical maximum from glucose. Our results demonstrate that carbon produced from electrocatalytically reduced CO2 can bolster chemical production in E. coli. This study shows that E. coli can be engineered towards carbon efficient methods of chemical production.
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Affiliation(s)
- Tanner R Treece
- Department of Chemistry, University of California, Davis, Davis, CA, 95616, USA
| | - Santanu Pattanayak
- Department of Chemistry, University of California, Davis, Davis, CA, 95616, USA
| | - Morgan M Matson
- Department of Chemistry, University of California, Davis, Davis, CA, 95616, USA
| | - Mateo M Cepeda
- Department of Chemistry, University of California, Davis, Davis, CA, 95616, USA
| | - Louise A Berben
- Department of Chemistry, University of California, Davis, Davis, CA, 95616, USA.
| | - Shota Atsumi
- Department of Chemistry, University of California, Davis, Davis, CA, 95616, USA.
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3
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El-Seedi HR, El-Mallah MF, Yosri N, Alajlani M, Zhao C, Mehmood MA, Du M, Ullah H, Daglia M, Guo Z, Khalifa SAM, Shou Q. Review of Marine Cyanobacteria and the Aspects Related to Their Roles: Chemical, Biological Properties, Nitrogen Fixation and Climate Change. Mar Drugs 2023; 21:439. [PMID: 37623720 PMCID: PMC10456358 DOI: 10.3390/md21080439] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Revised: 07/27/2023] [Accepted: 07/27/2023] [Indexed: 08/26/2023] Open
Abstract
Marine cyanobacteria are an ancient group of photosynthetic microbes dating back to 3.5 million years ago. They are prolific producers of bioactive secondary metabolites. Over millions of years, natural selection has optimized their metabolites to possess activities impacting various biological targets. This paper discusses the historical and existential records of cyanobacteria, and their role in understanding the evolution of marine cyanobacteria through the ages. Recent advancements have focused on isolating and screening bioactive compounds and their respective medicinal properties, and we also discuss chemical property space and clinical trials, where compounds with potential pharmacological effects, such as cytotoxicity, anticancer, and antiparasitic properties, are highlighted. The data have shown that about 43% of the compounds investigated have cytotoxic effects, and around 8% have anti-trypanosome activity. We discussed the role of different marine cyanobacteria groups in fixing nitrogen percentages on Earth and their outcomes in fish productivity by entering food webs and enhancing productivity in different agricultural and ecological fields. The role of marine cyanobacteria in the carbon cycle and their outcomes in improving the efficiency of photosynthetic CO2 fixation in the chloroplasts of crop plants, thus enhancing the crop plant's yield, was highlighted. Ultimately, climate changes have a significant impact on marine cyanobacteria where the temperature rises, and CO2 improves the cyanobacterial nitrogen fixation.
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Affiliation(s)
- Hesham R. El-Seedi
- International Research Center for Food Nutrition and Safety, Jiangsu University, Zhenjiang 212013, China
- International Joint Research Laboratory of Intelligent Agriculture and Agri-Products Processing, Jiangsu University, Jiangsu Education Department, Nanjing 210024, China
- Department of Chemistry, Faculty of Science, Islamic University of Madinah, Madinah 42351, Saudi Arabia
- Department of Chemistry, Faculty of Science, Menoufia University, Shebin El-Kom 32512, Egypt;
| | - Mohamed F. El-Mallah
- Department of Chemistry, Faculty of Science, Menoufia University, Shebin El-Kom 32512, Egypt;
| | - Nermeen Yosri
- Chemistry Department of Medicinal and Aromatic Plants, Research Institute of Medicinal and Aromatic Plants (RIMAP), Beni-Suef University, Beni-Suef 62514, Egypt;
- China Light Industry Key Laboratory of Food Intelligent Detection & Processing, School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, China;
| | - Muaaz Alajlani
- Faculty of Pharmacy, Al-Sham Private University, Damascus 0100, Syria;
| | - Chao Zhao
- College of Marine Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China;
| | - Muhammad A. Mehmood
- Bioenergy Research Center, Department of Bioinformatics and Biotechnology, Government College University Faisalabad, Faisalabad 38000, Pakistan
| | - Ming Du
- School of Food Science and Technology, National Engineering Research Center of Seafood, Dalian Polytechnic University, Dalian 116034, China;
| | - Hammad Ullah
- Department of Pharmacy, University of Napoli Federico II, Via D. Montesano 49, 80131 Naples, Italy
| | - Maria Daglia
- International Research Center for Food Nutrition and Safety, Jiangsu University, Zhenjiang 212013, China
- Department of Pharmacy, University of Napoli Federico II, Via D. Montesano 49, 80131 Naples, Italy
| | - Zhiming Guo
- China Light Industry Key Laboratory of Food Intelligent Detection & Processing, School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, China;
| | - Shaden A. M. Khalifa
- International Research Center for Food Nutrition and Safety, Jiangsu University, Zhenjiang 212013, China
- Psychiatry and Psychology Department, Capio Saint Göran’s Hospital, Sankt Göransplan 1, 112 19 Stockholm, Sweden
| | - Qiyang Shou
- Second Clinical Medical College, Jinhua Academy, Zhejiang Chinese Medical University, Hangzhou 310053, China
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Valotta A, Malihan-Yap L, Hinteregger K, Kourist R, Gruber-Woelfler H. Design and Investigation of a Photocatalytic Setup for Efficient Biotransformations Within Recombinant Cyanobacteria in Continuous Flow. CHEMSUSCHEM 2022; 15:e202201468. [PMID: 36069133 PMCID: PMC9828554 DOI: 10.1002/cssc.202201468] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Revised: 09/06/2022] [Indexed: 06/15/2023]
Abstract
Photo- and biocatalysis show many advantages as more sustainable solutions for the production of fine chemicals. In an effort to combine the benefits and the knowledge of both these areas, a continuous photobiocatalytic setup was designed and optimized to carry out whole-cell biotransformations within cells of the cyanobacterium Synechocystis sp. PCC 6803 expressing the gene of the ene-reductase YqjM from B. subtilis. The effect of the light intensity and flow rate on the specific activity in the stereoselective reduction of 2-methyl maleimide was investigated via a design-of-experiments approach. The cell density in the setup was further increased at the optimal operating conditions without loss in specific activity, demonstrating that the higher surface area/volume ratio in the coil reactor improved the illumination efficiency of the process. Furthermore, different reactor designs were compared, proving that the presented approach was the most cost- and time-effective solution for intensifying photobiotransformations within cyanobacterial cells.
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Affiliation(s)
- Alessia Valotta
- Institute of Process and Particle Engineering, Graz University of Technology, Inffeldgasse 13, 8010, Graz, Austria
| | - Lenny Malihan-Yap
- Institute of Molecular Biotechnology, Graz University of Technology, Petersgasse 14, 8010, Graz, Austria
| | - Kerstin Hinteregger
- Institute of Process and Particle Engineering, Graz University of Technology, Inffeldgasse 13, 8010, Graz, Austria
| | - Robert Kourist
- Institute of Molecular Biotechnology, Graz University of Technology, Petersgasse 14, 8010, Graz, Austria
- ACIB GmbH, Krenngasse 37, 8010, Graz, Austria
| | - Heidrun Gruber-Woelfler
- Institute of Process and Particle Engineering, Graz University of Technology, Inffeldgasse 13, 8010, Graz, Austria
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Light-Driven Synthetic Biology: Progress in Research and Industrialization of Cyanobacterial Cell Factory. LIFE (BASEL, SWITZERLAND) 2022; 12:life12101537. [PMID: 36294972 PMCID: PMC9605453 DOI: 10.3390/life12101537] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2022] [Revised: 09/21/2022] [Accepted: 09/29/2022] [Indexed: 11/07/2022]
Abstract
Light-driven synthetic biology refers to an autotrophic microorganisms-based research platform that remodels microbial metabolism through synthetic biology and directly converts light energy into bio-based chemicals. This technology can help achieve the goal of carbon neutrality while promoting green production. Cyanobacteria are photosynthetic microorganisms that use light and CO2 for growth and production. They thus possess unique advantages as "autotrophic cell factories". Various fuels and chemicals have been synthesized by cyanobacteria, indicating their important roles in research and industrial application. This review summarized the progresses and remaining challenges in light-driven cyanobacterial cell factory. The choice of chassis cells, strategies used in metabolic engineering, and the methods for high-value CO2 utilization will be discussed.
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Semi-continuous cultivation strategy for improving the growth of Synechocystis sp. PCC 6803 based on the growth model of volume average light intensity. ALGAL RES 2022. [DOI: 10.1016/j.algal.2022.102839] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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7
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Sheikh T, Hamid B, Baba Z, Iqbal S, Yatoo A, Fatima S, Nabi A, Kanth R, Dar K, Hussain N, Alturki AI, Sunita K, Sayyed R. Extracellular polymeric substances in psychrophilic cyanobacteria: A potential bioflocculant and carbon sink to mitigate cold stress. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2022. [DOI: 10.1016/j.bcab.2022.102375] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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8
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Matson MM, Cepeda MM, Zhang A, Case AE, Kavvas ES, Wang X, Carroll AL, Tagkopoulos I, Atsumi S. Adaptive laboratory evolution for improved tolerance of isobutyl acetate in Escherichia coli. Metab Eng 2021; 69:50-58. [PMID: 34763090 DOI: 10.1016/j.ymben.2021.11.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2021] [Revised: 10/14/2021] [Accepted: 11/04/2021] [Indexed: 02/08/2023]
Abstract
Previously, Escherichia coli was engineered to produce isobutyl acetate (IBA). Titers greater than the toxicity threshold (3 g/L) were achieved by using layer-assisted production. To avoid this costly and complex method, adaptive laboratory evolution (ALE) was applied to E. coli for improved IBA tolerance. Over 37 rounds of selective pressure, 22 IBA-tolerant mutants were isolated. Remarkably, these mutants not only tolerate high IBA concentrations, they also produce higher IBA titers. Using whole-genome sequencing followed by CRISPR/Cas9 mediated genome editing, the mutations (SNPs in metH, rho and deletion of arcA) that confer improved tolerance and higher titers were elucidated. The improved IBA titers in the evolved mutants were a result of an increased supply of acetyl-CoA and altered transcriptional machinery. Without the use of phase separation, a strain capable of 3.2-fold greater IBA production than the parent strain was constructed by combing select beneficial mutations. These results highlight the impact improved tolerance has on the production capability of a biosynthetic system.
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Affiliation(s)
- Morgan M Matson
- Department of Chemistry, University of California, Davis, CA, 95616, USA
| | - Mateo M Cepeda
- Department of Chemistry, University of California, Davis, CA, 95616, USA
| | - Angela Zhang
- Department of Chemistry, University of California, Davis, CA, 95616, USA
| | - Anna E Case
- Department of Chemistry, University of California, Davis, CA, 95616, USA
| | - Erol S Kavvas
- Genome Center, University of California, Davis, CA, 95616, USA
| | - Xiaokang Wang
- Genome Center, University of California, Davis, CA, 95616, USA; Department of Biomedical Engineering, University of California, Davis, CA 95616, USA
| | - Austin L Carroll
- Department of Chemistry, University of California, Davis, CA, 95616, USA
| | - Ilias Tagkopoulos
- Genome Center, University of California, Davis, CA, 95616, USA; Department of Computer Science, University of California, Davis, CA, 95616, USA
| | - Shota Atsumi
- Department of Chemistry, University of California, Davis, CA, 95616, USA.
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Durall C, Kukil K, Hawkes JA, Albergati A, Lindblad P, Lindberg P. Production of succinate by engineered strains of Synechocystis PCC 6803 overexpressing phosphoenolpyruvate carboxylase and a glyoxylate shunt. Microb Cell Fact 2021; 20:39. [PMID: 33557832 PMCID: PMC7871529 DOI: 10.1186/s12934-021-01529-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Accepted: 01/25/2021] [Indexed: 01/02/2023] Open
Abstract
BACKGROUND Cyanobacteria are promising hosts for the production of various industrially important compounds such as succinate. This study focuses on introduction of the glyoxylate shunt, which is naturally present in only a few cyanobacteria, into Synechocystis PCC 6803. In order to test its impact on cell metabolism, engineered strains were evaluated for succinate accumulation under conditions of light, darkness and anoxic darkness. Each condition was complemented by treatments with 2-thenoyltrifluoroacetone, an inhibitor of succinate dehydrogenase enzyme, and acetate, both in nitrogen replete and deplete medium. RESULTS We were able to introduce genes encoding the glyoxylate shunt, aceA and aceB, encoding isocitrate lyase and malate synthase respectively, into a strain of Synechocystis PCC 6803 engineered to overexpress phosphoenolpyruvate carboxylase. Our results show that complete expression of the glyoxylate shunt results in higher extracellular succinate accumulation compared to the wild type control strain after incubation of cells in darkness and anoxic darkness in the presence of nitrate. Addition of the inhibitor 2-thenoyltrifluoroacetone increased succinate titers in all the conditions tested when nitrate was available. Addition of acetate in the presence of the inhibitor further increased the succinate accumulation, resulting in high levels when phosphoenolpyruvate carboxylase was overexpressed, compared to control strain. However, the highest succinate titer was obtained after dark incubation of an engineered strain with a partial glyoxylate shunt overexpressing isocitrate lyase in addition to phosphoenolpyruvate carboxylase, with only 2-thenoyltrifluoroacetone supplementation to the medium. CONCLUSIONS Heterologous expression of the glyoxylate shunt with its central link to the tricarboxylic acid cycle (TCA) for acetate assimilation provides insight on the coordination of the carbon metabolism in the cell. Phosphoenolpyruvate carboxylase plays an important role in directing carbon flux towards the TCA cycle.
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Affiliation(s)
- Claudia Durall
- Microbial Chemistry, Department of Chemistry-Ångström, Uppsala University, Box 523, 751 20, Uppsala, Sweden
| | - Kateryna Kukil
- Microbial Chemistry, Department of Chemistry-Ångström, Uppsala University, Box 523, 751 20, Uppsala, Sweden
| | - Jeffrey A Hawkes
- Analytical Chemistry, Department of Chemistry-BMC, Uppsala University, Box 599, 751 20, Uppsala, Sweden
| | - Alessia Albergati
- Microbial Chemistry, Department of Chemistry-Ångström, Uppsala University, Box 523, 751 20, Uppsala, Sweden
| | - Peter Lindblad
- Microbial Chemistry, Department of Chemistry-Ångström, Uppsala University, Box 523, 751 20, Uppsala, Sweden
| | - Pia Lindberg
- Microbial Chemistry, Department of Chemistry-Ångström, Uppsala University, Box 523, 751 20, Uppsala, Sweden.
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10
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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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11
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Srivastava A, Varshney RK, Shukla P. Sigma Factor Modulation for Cyanobacterial Metabolic Engineering. Trends Microbiol 2020; 29:266-277. [PMID: 33229204 DOI: 10.1016/j.tim.2020.10.012] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2020] [Revised: 10/25/2020] [Accepted: 10/26/2020] [Indexed: 11/18/2022]
Abstract
Sigma (σ) factors are key regulatory proteins that control the transcription initiation in prokaryotes. In response to environmental or developmental cues, σ factors initiate the transcription of necessary genes responsible for maintaining a life-sustaining metabolic balance. Due to the significant role of σ factors in bacterial metabolism, their rational engineering for commercial metabolite production in photoautotrophic, cyanobacterial cells is a desirable venture. As cyanobacterial genomes typically encode multiple σ factors, effective execution of metabolic engineering efforts largely relies on uncovering the complicated gene regulatory network and further characterization of the members of σ factor regulatory circuits. This review outlines the prospects of σ factor in metabolic engineering of cyanobacteria, summarizes the challenges in the path towards an efficient strain construction and highlights the genomic context of putative regulators of cyanobacterial σ factors.
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Affiliation(s)
- Amit Srivastava
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, USA
| | - Rajeev K Varshney
- Center of Excellence in Genomics and Systems Biology, International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Patancheru, India
| | - Pratyoosh Shukla
- Enzyme Technology and Protein Bioinformatics Laboratory, Department of Microbiology, Maharshi Dayanand University, Rohtak-124001, Haryana, India.
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12
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13
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Kirsch F, Klähn S, Hagemann M. Salt-Regulated Accumulation of the Compatible Solutes Sucrose and Glucosylglycerol in Cyanobacteria and Its Biotechnological Potential. Front Microbiol 2019; 10:2139. [PMID: 31572343 PMCID: PMC6753628 DOI: 10.3389/fmicb.2019.02139] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Accepted: 08/30/2019] [Indexed: 12/11/2022] Open
Abstract
Cyanobacteria are prokaryotes that can assimilate inorganic carbon via oxygenic photosynthesis, which results in the formation of organic compounds essentially from CO2, water, and light. Increasing concerns regarding the increase in atmospheric CO2 due to fossil energy usage fueled the idea of a photosynthesis-driven and CO2-neutral, i.e., cyanobacteria-based biotechnology. The ability of various cyanobacteria to tolerate high and/or fluctuating salinities attenuates the requirement of freshwater for their cultivation, which makes these organisms even more interesting regarding a sustainable utilization of natural resources. However, those applications require a detailed knowledge of the processes involved in salt acclimation. Here, we review the current state of our knowledge on the regulation of compatible solute accumulation in cyanobacteria. The model organism Synechocystis sp. PCC 6803 responds to increasing salinities mainly by the accumulation of glucosylglycerol (GG) and sucrose. After exposure toward increased salt concentrations, the accumulation of the main compatible solute GG is achieved by de novo synthesis. The key target of regulation is the enzyme GG-phosphate synthase (GgpS) and involves transcriptional, posttranscriptional, and biochemical mechanisms. Recently, the GG-degrading enzyme GG hydrolase A (GghA) was identified, which is particularly important for GG degradation during exposure to decreasing salinities. The inversely ion-regulated activities of GgpS and GghA could represent the main model for effectively tuning GG steady state levels according to external salinities. Similar to GG, the intracellular amount of sucrose is also salt-regulated and seems to be determined by the balance of sucrose synthesis via sucrose-phosphate synthase (Sps) and its degradation via invertase (Inv). In addition to their role as stress protectants, both compatible solutes also represent promising targets for biotechnology. Hence, the increasing knowledge on the regulation of compatible solute accumulation not only improves our understanding of the stress physiology of cyanobacteria but will also support their future biotechnological applications.
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Affiliation(s)
- Friedrich Kirsch
- Department of Plant Physiology, Institute for Biosciences, University of Rostock, Rostock, Germany
| | - Stephan Klähn
- Department of Solar Materials, Helmholtz-Centre for Environmental Research-UFZ, Leipzig, Germany
| | - Martin Hagemann
- Department of Plant Physiology, Institute for Biosciences, University of Rostock, Rostock, Germany
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14
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Wang M, Luan G, Lu X. Systematic identification of a neutral site on chromosome of Synechococcus sp. PCC7002, a promising photosynthetic chassis strain. J Biotechnol 2019; 295:37-40. [PMID: 30853638 DOI: 10.1016/j.jbiotec.2019.02.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2018] [Revised: 02/01/2019] [Accepted: 02/08/2019] [Indexed: 12/01/2022]
Abstract
Cyanobacteria based photosynthetic biomanufacturing is supposed to be one of the alternative routes for sustainable production of biofuels and biochemicals. Synechococcus sp. PCC 7002 is a promising cyanobacterial chassis strain possessing desired properties for scaled cultivation in future. Development of cyanobacterial cell factories requires modifications of PCC7002 chromosome to expand the photosynthesis-based metabolism networks. Therefore, mining genomic neutral sites for stable integration of heterologous genes and pathways would be of great significance for expanding the toolbox for PCC7002 genome engineering. Here we demonstrate a paradigm for identification of potential neutral sites from chromosome of PCC7002 based on genomic and transcriptomics data. By refining the massive omics information from database, 51 putative sites with no significant physiological or metabolism effects were extracted as candidates. Combining genomic context analysis, a locus termed as NS0027 between two neighboring putative neutral genes was selected and evaluated as a neutral site for genetic integration. In addition, an ethanol synthesis pathway was introduced into the NS0027 site to assess the functionality of this site. The sites we identified and the strategy we adopted in this work would benefit the development of effective genetic toolbox and efficient photosynthetic cell factories based on PCC7002.
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Affiliation(s)
- Min Wang
- Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No. 189 Songling Road, Qingdao, 266101, China; Shandong Provincial Key Laboratory of Energy Genetics, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No. 189 Songling Road, Qingdao, 266101, China
| | - Guodong Luan
- Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No. 189 Songling Road, Qingdao, 266101, China; Shandong Provincial Key Laboratory of Synthetic Biology, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No. 189 Songling Road, Qingdao, 266101, China.
| | - Xuefeng Lu
- Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No. 189 Songling Road, Qingdao, 266101, China; Shandong Provincial Key Laboratory of Synthetic Biology, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No. 189 Songling Road, Qingdao, 266101, China; Dalian National Laboratory for Clean Energy, Dalian, China; Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China.
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15
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Gordon GC, Pfleger BF. Regulatory Tools for Controlling Gene Expression in Cyanobacteria. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1080:281-315. [PMID: 30091100 PMCID: PMC6662922 DOI: 10.1007/978-981-13-0854-3_12] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Cyanobacteria are attractive hosts for converting carbon dioxide and sunlight into desirable chemical products. To engineer these organisms and manipulate their metabolic pathways, the biotechnology community has developed genetic tools to control gene expression. Many native cyanobacterial promoters and related sequence elements have been used to regulate genes of interest, and heterologous tools that use non-native small molecules to induce gene expression have been demonstrated. Overall, IPTG-based induction systems seem to be leaky and initially demonstrate small dynamic ranges in cyanobacteria. Consequently, a variety of other induction systems have been optimized to enable tighter control of gene expression. Tools require significant optimization because they function quite differently in cyanobacteria when compared to analogous use in model heterotrophs. We hypothesize that these differences are due to fundamental differences in physiology between organisms. This review is not intended to summarize all known products made in cyanobacteria nor the performance (titer, rate, yield) of individual strains, but instead will focus on the genetic tools and the inherent aspects of cellular physiology that influence gene expression in cyanobacteria.
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Affiliation(s)
- Gina C Gordon
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI, USA
- Microbiology Doctoral Training Program, University of Wisconsin-Madison, Madison, WI, USA
| | - Brian F Pfleger
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI, USA.
- Microbiology Doctoral Training Program, University of Wisconsin-Madison, Madison, WI, USA.
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Kamravamanesh D, Lackner M, Herwig C. Bioprocess Engineering Aspects of Sustainable Polyhydroxyalkanoate Production in Cyanobacteria. Bioengineering (Basel) 2018; 5:bioengineering5040111. [PMID: 30567391 PMCID: PMC6315491 DOI: 10.3390/bioengineering5040111] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Revised: 12/13/2018] [Accepted: 12/15/2018] [Indexed: 11/16/2022] Open
Abstract
Polyhydroxyalkanoates (PHAs) are a group of biopolymers produced in various microorganisms as carbon and energy reserve when the main nutrient, necessary for growth, is limited. PHAs are attractive substitutes for conventional petrochemical plastics, as they possess similar material properties, along with biocompatibility and complete biodegradability. The use of PHAs is restricted, mainly due to the high production costs associated with the carbon source used for bacterial fermentation. Cyanobacteria can accumulate PHAs under photoautotrophic growth conditions using CO2 and sunlight. However, the productivity of photoautotrophic PHA production from cyanobacteria is much lower than in the case of heterotrophic bacteria. Great effort has been focused to reduce the cost of PHA production, mainly by the development of optimized strains and more efficient cultivation and recovery processes. Minimization of the PHA production cost can only be achieved by considering the design and a complete analysis of the whole process. With the aim on commercializing PHA, this review will discuss the advances and the challenges associated with the upstream processing of cyanobacterial PHA production, in order to help the design of the most efficient method on the industrial scale.
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Affiliation(s)
- Donya Kamravamanesh
- Institute of Chemical, Environmental and Bioscience Engineering, Research Area Biochemical Engineering, Technische Universität Wien, 1060 Vienna, Austria.
- Lackner Ventures and Consulting GmbH, Hofherr Schrantz Gasse 2, 1210 Vienna, Austria.
| | - Maximilian Lackner
- Lackner Ventures and Consulting GmbH, Hofherr Schrantz Gasse 2, 1210 Vienna, Austria.
- Institute of Industrial Engineering, University of Applied Sciences FH Technikum Wien, Höchstädtplatz 6, 1200 Vienna, Austria.
| | - Christoph Herwig
- Institute of Chemical, Environmental and Bioscience Engineering, Research Area Biochemical Engineering, Technische Universität Wien, 1060 Vienna, Austria.
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Arora NK, Fatima T, Mishra I, Verma M, Mishra J, Mishra V. Environmental sustainability: challenges and viable solutions. ACTA ACUST UNITED AC 2018. [DOI: 10.1007/s42398-018-00038-w] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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18
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Noreña-Caro D, Benton MG. Cyanobacteria as photoautotrophic biofactories of high-value chemicals. J CO2 UTIL 2018. [DOI: 10.1016/j.jcou.2018.10.008] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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19
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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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20
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Surface Display of Small Affinity Proteins on Synechocystis sp. Strain PCC 6803 Mediated by Fusion to the Major Type IV Pilin PilA1. J Bacteriol 2018; 200:JB.00270-18. [PMID: 29844032 DOI: 10.1128/jb.00270-18] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Accepted: 05/22/2018] [Indexed: 11/20/2022] Open
Abstract
Functional surface display of small affinity proteins, namely, affibodies (6.5 kDa), was evaluated for the model cyanobacterium Synechocystis sp. strain PCC 6803 through anchoring to native surface structures. These structures included confirmed or putative subunits of the type IV pili, the S-layer protein, and the heterologous Escherichia coli autotransporter antigen 43 system. The most stable display system was determined to be through C-terminal fusion to PilA1, the major type IV pilus subunit in Synechocystis, in a strain unable to retract these pili (ΔpilT1). Type IV pilus synthesis was upheld, albeit reduced, when fusion proteins were incorporated. However, pilus-mediated functions, such as motility and transformational competency, were negatively affected. Display of affibodies on Synechocystis and the complementary anti-idiotypic affibodies on E. coli or Staphylococcus carnosus was able to mediate interspecies cell-cell binding by affibody complex formation. The same strategy, however, was not able to drive cell-cell binding and aggregation of Synechocystis-only mixtures. Successful affibody tagging of the putative minor pilin PilA4 showed that it locates to the type IV pili in Synechocystis and that its extracellular availability depends on PilA1. In addition, affibody tagging of the S-layer protein indicated that the domains responsible for the anchoring and secretion of this protein are located at the N and C termini, respectively. This study can serve as a basis for future surface display of proteins on Synechocystis for biotechnological applications.IMPORTANCE Cyanobacteria are gaining interest for their potential as autotrophic cell factories. Development of efficient surface display strategies could improve their suitability for large-scale applications by providing options for designed microbial consortia, cell immobilization, and biomass harvesting. Here, surface display of small affinity proteins was realized by fusing them to the major subunit of the native type IV pili in Synechocystis sp. strain PCC 6803. The display of complementary affinity proteins allowed specific cell-cell binding between Synechocystis and Escherichia coli or Staphylococcus carnosus Additionally, successful tagging of the putative pilin PilA4 helped determine its localization to the type IV pili. Analogous tagging of the S-layer protein shed light on the regions involved in its secretion and surface anchoring.
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Chin T, Okuda Y, Ikeuchi M. Sorbitol production and optimization of photosynthetic supply in the cyanobacterium Synechocystis PCC 6803. J Biotechnol 2018; 276-277:25-33. [PMID: 29684388 DOI: 10.1016/j.jbiotec.2018.04.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Revised: 03/20/2018] [Accepted: 04/10/2018] [Indexed: 11/15/2022]
Abstract
Biochemicals production is a major theme in the application of photosynthesis to address global warming and organic-resource problems. Among biochemicals, sugar alcohols have attracted research attention because they are directly derived from two photosynthetic products, sugars and reductants. Here, we produced sorbitol photosynthetically by using cyanobacteria and modified the supply of its substrates through genetic engineering. Expression of an NADPH-dependent enzyme that generates sorbitol-6-phosphate, S6PDH, was highly toxic to cyanobacteria likely due to the sorbitol production, whereas expression of an NADH-dependent enzyme, SrlD2, yielded no sorbitol. The toxicity was partly overcome by introducing a theophylline-inducible riboswitch for S6PDH expression and optimizing induction, but sorbitol production was still low and severely inhibited growth. Co-expression of fructose-1,6-bisphosphatase drastically alleviated the growth inhibition, but did not increase short-term sorbitol production. The NADPH/NADP+ ratio decreased during sorbitol production. Overexpression of a membrane-bound transhydrogenase for NADPH generation from NADH elevated the short-term sorbitol production, but only partly alleviated the growth inhibition. Notably, a strain overexpressing all three enzymes exhibited sustainable sorbitol production at 312 mg/L, which was nearly 27-fold higher than the yield of the initial S6PDH-overexpressing strain. We discuss these results in relation to the optimization of photosynthetic supply for sorbitol production in cyanobacteria.
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Affiliation(s)
- Taejun Chin
- Department of Life Sciences (Biolgy), Graduate School of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo 153-8902, Japan
| | - Yukiko Okuda
- Core Research for Evolutional Science and Technology, Japan Science and Technology Agency, 4-1-8 Honcho Kawaguchi, Saitama 332-0012, Japan
| | - Masahiko Ikeuchi
- Department of Life Sciences (Biolgy), Graduate School of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo 153-8902, Japan; Core Research for Evolutional Science and Technology, Japan Science and Technology Agency, 4-1-8 Honcho Kawaguchi, Saitama 332-0012, Japan.
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22
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Photomixotrophic chemical production in cyanobacteria. Curr Opin Biotechnol 2018; 50:65-71. [DOI: 10.1016/j.copbio.2017.11.008] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Revised: 11/11/2017] [Accepted: 11/13/2017] [Indexed: 11/19/2022]
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23
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Tashiro Y, Hirano S, Matson MM, Atsumi S, Kondo A. Electrical-biological hybrid system for CO 2 reduction. Metab Eng 2018; 47:211-218. [PMID: 29580924 DOI: 10.1016/j.ymben.2018.03.015] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 03/16/2018] [Accepted: 03/16/2018] [Indexed: 12/24/2022]
Abstract
Here we have developed an electrochemical-biological hybrid system to fix CO2. Natural biological CO2 fixation processes are relatively slow. To increase the speed of fixation we applied electrocatalysts to reduce CO2 to formate. We chose a user-friendly organism, Escherichia coli, as host. Overall, the newly constructed CO2 and formate fixation pathway converts two formate and one CO2 to one pyruvate via glycine and L-serine in E. coli. First, one formate and one CO2 are converted to one glycine. Second, L-serine is produced from one glycine and one formate. Lastly, L-serine is converted to pyruvate. E. coli's genetic tractability allowed us to balance various parameters of the pathway. The carbon flux of the pathway was sufficient to compensate L-serine auxotrophy in the strain. In total, we integrated both electrocatalysis and biological systems into a single pot to support E. coli growth with CO2 and electricity. Results show promise for using this hybrid system for chemical production from CO2 and electricity.
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Affiliation(s)
- Yohei Tashiro
- Center for Sustainable Resource Science, RIKEN, 1-7-22, Suehiro-cho, Tsurimi-ku, Yokohama, Kanagawa 230-0045, Japan; Department of Chemistry, University of California, One Shields Ave, Davis, CA 95616, USA
| | - Shinichi Hirano
- Environmental Science Research Laboratory, Central Research Institute of Electric Power Industry, 1646 Abiko, Abiko, Chiba 270-1194, Japan
| | - Morgan M Matson
- Department of Chemistry, University of California, One Shields Ave, Davis, CA 95616, USA
| | - Shota Atsumi
- Department of Chemistry, University of California, One Shields Ave, Davis, CA 95616, USA.
| | - Akihiko Kondo
- Center for Sustainable Resource Science, RIKEN, 1-7-22, Suehiro-cho, Tsurimi-ku, Yokohama, Kanagawa 230-0045, Japan; Department of Chemical Science and Engineering, Graduate School of Engineering, Kobe University, 1-1 Rokkodai, Nada, Kobe 657-8501, Japan.
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24
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Methods for enhancing cyanobacterial stress tolerance to enable improved production of biofuels and industrially relevant chemicals. Appl Microbiol Biotechnol 2018; 102:1617-1628. [DOI: 10.1007/s00253-018-8755-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Revised: 01/03/2018] [Accepted: 01/04/2018] [Indexed: 10/18/2022]
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25
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Production of Bioplastic Compounds by Genetically Manipulated and Metabolic Engineered Cyanobacteria. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1080:155-169. [DOI: 10.1007/978-981-13-0854-3_7] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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26
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Woo HM. Metabolic pathway rewiring in engineered cyanobacteria for solar-to-chemical and solar-to-fuel production from CO 2. Bioengineered 2018; 9:2-5. [PMID: 28430539 PMCID: PMC5972923 DOI: 10.1080/21655979.2017.1317572] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Photoautotrophic cyanobacteria have been developed to convert CO2 to valuable chemicals and fuels as solar-to-chemical (S2C) and solar-to-fuel (S2F) platforms. Here, I describe the rewiring of the metabolic pathways in cyanobacteria to better understand the endogenous carbon flux and to enhance the yield of heterologous products. The plasticity of the cyanobacterial metabolism has been proposed to be advantageous for the development of S2C and S2F processes. The rewiring of the sugar catabolism and of the phosphoketolase pathway in the central cyanobacterial metabolism allowed for an enhancement in the level of target products by redirecting the carbon fluxes. Thus, metabolic pathway rewiring can promote the development of more efficient cyanobacterial cell factories for the generation of feasible S2C and S2F platforms.
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Affiliation(s)
- Han Min Woo
- a Department of Food Science and Biotechnology , Sungkyunkwan University (SKKU) , Jangan-gu, Suwon , Republic of Korea
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27
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Higo A, Isu A, Fukaya Y, Hisabori T. Spatio-Temporal Gene Induction Systems in the Heterocyst-Forming Multicellular Cyanobacterium Anabaena sp. PCC 7120. PLANT & CELL PHYSIOLOGY 2018; 59:82-89. [PMID: 29088489 DOI: 10.1093/pcp/pcx163] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Accepted: 10/22/2017] [Indexed: 06/07/2023]
Abstract
In the last decade, much progress has been made in the photosynthetic production of valuable products using unicellular cyanobacteria. However, production of some products requires dark, anaerobic incubation, which prevents practical applications using these organisms. Anabaena sp. PCC 7120 (A. 7120) is a heterocyst-forming multicellular cyanobacterium that is easy to manipulate genetically. Upon nitrogen step-down, this strain differentiates heterocysts that retain micro-oxic conditions for nitrogen fixation. We have developed gene regulation tools in this cyanobacterium. However, lack of a cell type-specific gene induction system has prevented A. 7120 from becoming a bona fide attractive host for photosynthetic production. We validated the usability of two transcriptional ON riboswitches that respond to theophylline or adenine. We then created a cell type-specific gene induction system by combining the riboswitches and promoters specific to either heterocysts or vegetative cells. We also created another cell type-specific gene induction system using small RNA that activates translation. Consequently, our study has expanded the toolbox for gene regulation in cyanobacteria and has enabled spatio-temporal gene induction in multicellular cyanobacteria.
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Affiliation(s)
- Akiyoshi Higo
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, Nagatsuta 4259-R1-8, Midori-ku, Yokohama, 226-8503, Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), 4-1-8 Honcho Kawaguchi, Saitama 332-0012, Japan
| | - Atsuko Isu
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, Nagatsuta 4259-R1-8, Midori-ku, Yokohama, 226-8503, Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), 4-1-8 Honcho Kawaguchi, Saitama 332-0012, Japan
| | - Yuki Fukaya
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, Nagatsuta 4259-R1-8, Midori-ku, Yokohama, 226-8503, Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), 4-1-8 Honcho Kawaguchi, Saitama 332-0012, Japan
| | - Toru Hisabori
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, Nagatsuta 4259-R1-8, Midori-ku, Yokohama, 226-8503, Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), 4-1-8 Honcho Kawaguchi, Saitama 332-0012, Japan
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28
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Nozzi NE, Case AE, Carroll AL, Atsumi S. Systematic Approaches to Efficiently Produce 2,3-Butanediol in a Marine Cyanobacterium. ACS Synth Biol 2017; 6:2136-2144. [PMID: 28718632 DOI: 10.1021/acssynbio.7b00157] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Cyanobacteria have attracted significant interest as a platform for renewable production of fuel and feedstock chemicals from abundant atmospheric carbon dioxide by way of photosynthesis. While great strides have been made in developing this technology in freshwater cyanobacteria, logistical issues remain in scale-up. Use of the cyanobacterium Synechococcus sp. PCC 7002 (7002) as a chemical production chassis could address a number of these issues given the higher tolerance to salt, light, and heat as well as the fast growth rate of 7002 in comparison to traditional model cyanobacteria such as Synechococcus elongatus PCC 7942 and Synechocystis sp. PCC 6803. However, despite growing interest, the development of genetic engineering tools for 7002 continues to lag behind those available for model cyanobacterial strains. In this work we demonstrate the systematic development of a 7002 production strain for the feedstock chemical 2,3-butanediol (23BD). We expand the range of tools available for use in 7002 by identifying and utilizing new integration sites for homologous recombination, demonstrating the inducibility of theophylline riboswitches, and screening a set of isopropyl β-d-1-thiogalactopyranoside (IPTG) inducible promoters. We then demonstrate improvements of 23BD production with the systematic screening of different conditions including: operon arrangement and copy number, light strength, inducer concentration, cell density at the time of induction, and nutrient concentration. Final production tests yielded titers of 1.6 g/L 23BD after 16 days at a rate of 100 mg/L/day. This work represents great strides in the development of 7002 as an industrially relevant production host.
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Affiliation(s)
- Nicole E. Nozzi
- Department of Chemistry, University of California, Davis, One Shields Avenue, Davis, California 95616, United States
| | - Anna E. Case
- Department of Chemistry, University of California, Davis, One Shields Avenue, Davis, California 95616, United States
| | - Austin L. Carroll
- Department of Chemistry, University of California, Davis, One Shields Avenue, Davis, California 95616, United States
| | - Shota Atsumi
- Department of Chemistry, University of California, Davis, One Shields Avenue, Davis, California 95616, United States
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29
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Zhang A, Carroll AL, Atsumi S. Carbon recycling by cyanobacteria: improving CO2 fixation through chemical production. FEMS Microbiol Lett 2017; 364:4058408. [DOI: 10.1093/femsle/fnx165] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Accepted: 07/29/2017] [Indexed: 11/14/2022] Open
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30
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Global metabolic rewiring for improved CO 2 fixation and chemical production in cyanobacteria. Nat Commun 2017; 8:14724. [PMID: 28287087 PMCID: PMC5355792 DOI: 10.1038/ncomms14724] [Citation(s) in RCA: 118] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2016] [Accepted: 01/25/2017] [Indexed: 01/10/2023] Open
Abstract
Cyanobacteria have attracted much attention as hosts to recycle CO2 into valuable chemicals. Although cyanobacteria have been engineered to produce various compounds, production efficiencies are too low for commercialization. Here we engineer the carbon metabolism of Synechococcus elongatus PCC 7942 to improve glucose utilization, enhance CO2 fixation and increase chemical production. We introduce modifications in glycolytic pathways and the Calvin Benson cycle to increase carbon flux and redirect it towards carbon fixation. The engineered strain efficiently uses both CO2 and glucose, and produces 12.6 g l−1 of 2,3-butanediol with a rate of 1.1 g l−1 d−1 under continuous light conditions. Removal of native regulation enables carbon fixation and 2,3-butanediol production in the absence of light. This represents a significant step towards industrial viability and an excellent example of carbon metabolism plasticity. Cyanobacteria are promising biofactories to reduce atmospheric CO2 and convert it into chemicals. Here the authors engineer Synechococcus elongatus carbon metabolism to increase 2,3-butanediol production from glucose and CO2 under light and dark conditions.
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31
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Higo A, Isu A, Fukaya Y, Hisabori T. Designing Synthetic Flexible Gene Regulation Networks Using RNA Devices in Cyanobacteria. ACS Synth Biol 2017; 6:55-61. [PMID: 27636301 DOI: 10.1021/acssynbio.6b00201] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
In recent years, studies on the development of gene regulation tools in cyanobacteria have been extensively conducted toward efficient production of valuable chemicals. However, there is considerable scope for improving the economic feasibility of production. To improve a recently reported gene induction system using anhydrotetracycline (aTc)-TetR and an endogenous gene repression system using small antisense RNA in the filamentous nitrogen-fixing cyanobacterium Anabaena sp. PCC 7120 (Anabaena), we constructed a positive feedback loop, in which gfp and a small antisense RNA for tetR are controlled by an aTc-inducible promoter. GFP expression in this improved system was higher and longer than the system lacking tetR repression. In addition, by using TetR aptamer and a riboswitch, we succeeded in achieving a superior and longer induction of GFP expression even under high-light conditions. Hence, efficient gene induction systems were established in Anabaena by designing a gene regulation network using RNA-based tools.
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Affiliation(s)
- Akiyoshi Higo
- Laboratory
for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, Nagatsuta 4259-R1-8, Midori-ku, Yokohama 226-8503, Japan
- Core
Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Tokyo 102-0075, Japan
| | - Atsuko Isu
- Laboratory
for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, Nagatsuta 4259-R1-8, Midori-ku, Yokohama 226-8503, Japan
- Core
Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Tokyo 102-0075, Japan
| | - Yuki Fukaya
- Laboratory
for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, Nagatsuta 4259-R1-8, Midori-ku, Yokohama 226-8503, Japan
- Core
Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Tokyo 102-0075, Japan
| | - Toru Hisabori
- Laboratory
for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, Nagatsuta 4259-R1-8, Midori-ku, Yokohama 226-8503, Japan
- Core
Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Tokyo 102-0075, Japan
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32
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Kanno M, Atsumi S. Engineering an Obligate Photoautotrophic Cyanobacterium to Utilize Glycerol for Growth and Chemical Production. ACS Synth Biol 2017; 6:69-75. [PMID: 27643408 DOI: 10.1021/acssynbio.6b00239] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Cyanobacteria have attracted much attention as a means to directly recycle carbon dioxide into valuable chemicals that are currently produced from petroleum. However, the titers and productivities achieved are still far below the level required in industry. To make a more industrially applicable production scheme, glycerol, a byproduct of biodiesel production, can be used as an additional carbon source for photomixotrophic chemical production. Glycerol is an ideal candidate due to its availability and low cost. In this study, we found that a heterologous glycerol respiratory pathway enabled Synechococcus elongatus PCC 7942 to utilize extracellular glycerol. The engineered strain produced 761 mg/L of 2,3-butanediol in 48 h with a 290% increase over the control strain under continuous light conditions. Glycerol supplementation also allowed for continuous cell growth and 2,3-butanediol production in diurnal light conditions. These results highlight the potential of glycerol as an additional carbon source for photomixotrophic chemical production in cyanobacteria.
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Affiliation(s)
- Masahiro Kanno
- Department
of Chemistry, University of California, Davis, One Shields Avenue, Davis, California 95616, United States
- Asahi Kasei Corporation, 2-1
Samejima, Fuji, Shizuoka 416-8501, Japan
| | - Shota Atsumi
- Department
of Chemistry, University of California, Davis, One Shields Avenue, Davis, California 95616, United States
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33
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Woo HM. Solar-to-chemical and solar-to-fuel production from CO 2 by metabolically engineered microorganisms. Curr Opin Biotechnol 2017; 45:1-7. [PMID: 28088091 DOI: 10.1016/j.copbio.2016.11.017] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Revised: 11/16/2016] [Accepted: 11/23/2016] [Indexed: 01/01/2023]
Abstract
Recent development of carbon capture utilization (CCU) for reduction of greenhouse gas emission are reviewed. In the case of CO2 utilization, I describe development of solar-to-chemical and solar-to-fuel technology that refers to the use of solar energy to convert CO2 to desired chemicals and fuels. Photoautotrophic cyanobacterial platforms have been extensively developed on this principle, producing a diverse range of alcohols, organic acids, and isoprenoids directly from CO2. Recent breakthroughs in the metabolic engineering of cyanobacteria were reviewed. In addition, adoption of the light harvesting mechanisms from nature, photovoltaics-derived water splitting technologies have recently been integrated with microbial biotechnology to produce desired chemicals. Studies on the integration of electrode material with next-generation microbes are showcased for alternative solar-to-chemical and solar-to-fuel platforms.
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Affiliation(s)
- 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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