1
|
Yang S, Zhang Y, Li C, Tan X. Repurposing endogenous Type I-D CRISPR-Cas system for genome editing in Synechococcus sp. PCC7002. Microbiol Res 2024; 288:127884. [PMID: 39226667 DOI: 10.1016/j.micres.2024.127884] [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: 06/03/2024] [Revised: 07/29/2024] [Accepted: 08/25/2024] [Indexed: 09/05/2024]
Abstract
Synechococcus sp. PCC7002 has been considered as a photosynthetic chassis for the conversion of CO2 into biochemicals through genetic modification. However, conventional genetic manipulation techniques prove inadequate for comprehensive genetic modifications in this strain. Here, we present the development of a genome editing tool tailored for S. PCC7002, leveraging its endogenous type I-D CRISPR-Cas system. Utilizing this novel tool, we successfully deleted the glgA1 gene and iteratively edited the genome to obtain a double mutant of glgA1 and glgA2 genes. Additionally, large DNA fragments encompassing the entire type I-A (∼14 kb) or III-B CRISPR-Cas (∼21 kb) systems were completely knocked-out in S. PCC7002 using our tool. Furthermore, the endogenous pAQ5 plasmid, approximately 38 kb in length, was successfully cured from S. PCC7002. Our work demonstrates the feasibility of harnessing the endogenous CRISPR-Cas system for genome editing in S. PCC7002, thereby enriching the genetic toolkit for this species and providing a foundation for future enhancements in its biosynthetic efficiency.
Collapse
Affiliation(s)
- Shuxiao Yang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, and School of Life Sciences, Hubei University, Wuhan 430062, China
| | - Yongjiu Zhang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, and School of Life Sciences, Hubei University, Wuhan 430062, China
| | - Chunyan Li
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, and School of Life Sciences, Hubei University, Wuhan 430062, China
| | - Xiaoming Tan
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, and School of Life Sciences, Hubei University, Wuhan 430062, China.
| |
Collapse
|
2
|
Victoria AJ, Selão TT, Moreno-Cabezuelo JÁ, Mills LA, Gale GAR, Lea-Smith DJ, McCormick AJ. A toolbox to engineer the highly productive cyanobacterium Synechococcus sp. PCC 11901. PLANT PHYSIOLOGY 2024; 196:1674-1690. [PMID: 38713768 PMCID: PMC11444289 DOI: 10.1093/plphys/kiae261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2024] [Revised: 04/09/2024] [Accepted: 04/14/2024] [Indexed: 05/09/2024]
Abstract
Synechococcus sp. PCC 11901 (PCC 11901) is a fast-growing marine cyanobacterial strain that has a capacity for sustained biomass accumulation to very high cell densities, comparable to that achieved by commercially relevant heterotrophic organisms. However, genetic tools to engineer PCC 11901 for biotechnology applications are limited. Here we describe a suite of tools based on the CyanoGate MoClo system to unlock the engineering potential of PCC 11901. First, we characterized neutral sites suitable for stable genomic integration that do not affect growth even at high cell densities. Second, we tested a suite of constitutive promoters, terminators, and inducible promoters including a 2,4-diacetylphloroglucinol (DAPG)-inducible PhlF repressor system, which has not previously been demonstrated in cyanobacteria and showed tight regulation and a 228-fold dynamic range of induction. Lastly, we developed a DAPG-inducible dCas9-based CRISPR interference (CRISPRi) system and a modular method to generate markerless mutants using CRISPR-Cas12a. Based on our findings, PCC 11901 is highly responsive to CRISPRi-based repression and showed high efficiencies for single insertion (31% to 81%) and multiplex double insertion (25%) genome editing with Cas12a. We envision that these tools will lay the foundations for the adoption of PCC 11901 as a robust model strain for engineering biology and green biotechnology.
Collapse
Affiliation(s)
- Angelo J Victoria
- Institute of Molecular Plant Sciences, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3BF, UK
- Centre for Engineering Biology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3BF, UK
| | - Tiago Toscano Selão
- Department of Chemical and Environmental Engineering, University of Nottingham, Nottingham NG7 2RD, UK
| | | | - Lauren A Mills
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK
| | - Grant A R Gale
- Institute of Molecular Plant Sciences, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3BF, UK
- Centre for Engineering Biology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3BF, UK
| | - David J Lea-Smith
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK
| | - Alistair J McCormick
- Institute of Molecular Plant Sciences, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3BF, UK
- Centre for Engineering Biology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3BF, UK
| |
Collapse
|
3
|
Chen XY, Yu DJ, Jia R. Screening high-efficiency promoter to construct trans-vp28 gene Anabaena sp. PCC7120 against white spot syndrome virus of Litopenaeus vannamei. FISH & SHELLFISH IMMUNOLOGY 2024; 154:109912. [PMID: 39299405 DOI: 10.1016/j.fsi.2024.109912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2024] [Revised: 09/15/2024] [Accepted: 09/17/2024] [Indexed: 09/22/2024]
Abstract
This study aimed to select high-quality promoters to construct trans-vp28 gene Anabaena sp. PCC7120 and feed Litopenaeus vannamei to assess the effect of L.vannamei against white spot syndrome virus (WSSV). Transgenic algae were created using five plasmids containing PrbcL, Pcpc560, Ptrc, Ptac, and PpsbA. According to the gene expression efficiency and the growth index of transgenic algae, Pcpc560 was determined to be the most efficient promoter. Shrimps were continuously fed trans-vp28 gene Anabaena sp. PCC7120 for one week and then challenged with WSSV. After the challenge, the transgenic algae group (vp28-7120 group) was continuously immunized [continuous immunization for 0 days (vp28-7120-0d); continuous immunization for 2 days (vp28-7120-2d); continuous immunization for 4 days (vp28-7120-4d)]. After seven days, the daily survival rate of each experimental group was continuously tracked. Following the viral challenge, the hepatopancreas samples were assayed for their levels of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), thioredoxin peroxidase (TPX), acid phosphatase (ACP), and alkaline phosphatase (AKP) at varying time intervals. In comparison to the positive control group (challenge and no vaccination) and the wild-type group (challenge, fed wild-type Anabaena sp. PCC7120), the vp28-7120 group (challenge, fed trans-vp28 gene Anabaena sp. PCC7120) exhibited a remarkable increase in survival rates, reaching 50 % (vp28-7120-0d), 76.67 % (vp28-7120-2d), and 80 % (vp28-7120-4d). Furthermore, the vp28-7120 group consistently displayed significantly higher activities of SOD, CAT, GSH-Px, ACP, and AKP, while exhibiting notably lower TPX activity, when compared to the control group. These results indicate that the Pcpc560 promoter effectively elevated the expression level of the exogenous vp28 gene and spurred the growth of the trans-vp28 gene Anabaena sp. PCC7120. Consequently, trans-vp28 gene Anabaena sp. PCC7120 significantly bolstered the immunity of L.vannamei. Therefore, utilizing the Pcpc560 promoter to develop trans-vp28 gene Anabaena sp. PCC7120 based oral vaccine is highly beneficial for industrial-scale cultivation, advancing its commercialization prospects.
Collapse
Affiliation(s)
- Xin-Yu Chen
- College of Marine Science and Ecological Environment, Shanghai Ocean University, Shanghai, 201306, China
| | - Dian-Jiang Yu
- College of Life Sciences, Xiamen University, Xiamen, 361104, China
| | - Rui Jia
- College of Marine Science and Ecological Environment, Shanghai Ocean University, Shanghai, 201306, China; Marine Biomedical Science and Technology Innovation Platform of Lin-gang Special Area, Shanghai, 201306, China.
| |
Collapse
|
4
|
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.
Collapse
Affiliation(s)
| | | | - Jinlu Hu
- School of Life Sciences, Northwestern Polytechnical University, Xi’an 710072, China; (X.L.); (K.T.)
| |
Collapse
|
5
|
Joseph FM, Kaldenhoff R. Tobacco aquaporin NtAQP1 and human aquaporin hAQP1 contribute to single cell photosynthesis in Synechococcus. Biol Cell 2024; 116:e2470003. [PMID: 38653736 DOI: 10.1111/boc.202470003] [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: 01/10/2024] [Revised: 03/02/2024] [Accepted: 03/06/2024] [Indexed: 04/25/2024]
Abstract
BACKGROUND INFORMATION Aquaporins are H2O-permeable membrane protein pores. However, some aquaporins are also permeable to other substances such as CO2. In higher plants, overexpression of such aquaporins has already led to an enhanced photosynthetic performance due to improved CO2 mesophyll conductance. In this work, we investigated the effects of such aquaporins on unicellular photosynthetically active organisms, specifically cyanobacteria. RESULTS Overexpression of aquaporins NtAQP1 or hAQP1 that might have a function to improve CO2 membrane permeability lead to increased photosynthesis rates in the cyanobacterium Synechococcus sp. PCC7002 as concluded by the rate of evolved O2. A shift in the Plastoquinone pool state of the cells supports our findings. Water permeable aquaporins without CO2 permeability, such as NtPIP2;1, do not have this effect. CONCLUSIONS AND SIGNIFICANCE We conclude that also in single cell organisms like cyanobacteria, membrane CO2 conductivity could be rate limiting and CO2-porins reduce the respective membrane resistance. We could show that besides the tobacco aquaporin NtAQP1 also the human hAQP1 most likely functions as CO2 diffusion facilitator in the photosynthesis assay.
Collapse
Affiliation(s)
- Franziska M Joseph
- Department of Biology, Applied Plant Sciences, Technical University of Darmstadt, Darmstadt, Germany
| | - Ralf Kaldenhoff
- Department of Biology, Applied Plant Sciences, Technical University of Darmstadt, Darmstadt, Germany
| |
Collapse
|
6
|
Angulo-Cánovas E, Bartual A, López-Igual R, Luque I, Radzinski NP, Shilova I, Anjur-Dietrich M, García-Jurado G, Úbeda B, González-Reyes JA, Díez J, Chisholm SW, García-Fernández JM, del Carmen Muñoz-Marín M. Direct interaction between marine cyanobacteria mediated by nanotubes. SCIENCE ADVANCES 2024; 10:eadj1539. [PMID: 38781331 PMCID: PMC11114229 DOI: 10.1126/sciadv.adj1539] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Accepted: 04/16/2024] [Indexed: 05/25/2024]
Abstract
Microbial associations and interactions drive and regulate nutrient fluxes in the ocean. However, physical contact between cells of marine cyanobacteria has not been studied thus far. Here, we show a mechanism of direct interaction between the marine cyanobacteria Prochlorococcus and Synechococcus, the intercellular membrane nanotubes. We present evidence of inter- and intra-genus exchange of cytoplasmic material between neighboring and distant cells of cyanobacteria mediated by nanotubes. We visualized and measured these structures in xenic and axenic cultures and in natural samples. We show that nanotubes are produced between living cells, suggesting that this is a relevant system of exchange material in vivo. The discovery of nanotubes acting as exchange bridges in the most abundant photosynthetic organisms in the ocean may have important implications for their interactions with other organisms and their population dynamics.
Collapse
Affiliation(s)
- Elisa Angulo-Cánovas
- Departamento de Bioquímica y Biología Molecular, Campus de Excelencia Internacional Agroalimentario, Universidad de Córdoba, Córdoba 14014, Spain
| | - Ana Bartual
- Instituto Universitario de Investigaciones Marinas (INMAR), Campus de Excelencia Internacional del Mar (CEI·MAR), Universidad de Cádiz, 11510 Puerto Real, Cádiz, Spain
| | - Rocío López-Igual
- Instituto de Bioquímica Vegetal y Fotosíntesis, Consejo Superior de Investigaciones Científicas and Universidad de Sevilla, 41092 Sevilla, Spain
| | - Ignacio Luque
- Instituto de Bioquímica Vegetal y Fotosíntesis, Consejo Superior de Investigaciones Científicas and Universidad de Sevilla, 41092 Sevilla, Spain
| | - Nikolai P. Radzinski
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | | | - Maya Anjur-Dietrich
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Gema García-Jurado
- Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), Córdoba, Spain
| | - Bárbara Úbeda
- Instituto Universitario de Investigaciones Marinas (INMAR), Campus de Excelencia Internacional del Mar (CEI·MAR), Universidad de Cádiz, 11510 Puerto Real, Cádiz, Spain
| | - José Antonio González-Reyes
- Departamento de Biología Celular, Fisiología e Inmunología, Campus de Excelencia Internacional Agroalimentario, Universidad de Córdoba, Córdoba 14014, Spain
| | - Jesús Díez
- Departamento de Bioquímica y Biología Molecular, Campus de Excelencia Internacional Agroalimentario, Universidad de Córdoba, Córdoba 14014, Spain
| | - Sallie W. Chisholm
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - José Manuel García-Fernández
- Departamento de Bioquímica y Biología Molecular, Campus de Excelencia Internacional Agroalimentario, Universidad de Córdoba, Córdoba 14014, Spain
| | - María del Carmen Muñoz-Marín
- Departamento de Bioquímica y Biología Molecular, Campus de Excelencia Internacional Agroalimentario, Universidad de Córdoba, Córdoba 14014, Spain
| |
Collapse
|
7
|
Dranseike D, Cui Y, Ling AS, Donat F, Bernhard S, Bernero M, Areeckal A, Qin XH, Oakey JS, Dillenburger B, Studart AR, Tibbitt MW. Dual carbon sequestration with photosynthetic living materials. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.22.572991. [PMID: 38187760 PMCID: PMC10769394 DOI: 10.1101/2023.12.22.572991] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2024]
Abstract
Natural ecosystems offer efficient pathways for carbon sequestration, serving as a resilient approach to remove CO2 from the atmosphere with minimal environmental impact. However, the control of living systems outside of their native environments is often challenging. Here, we engineered a photosynthetic living material for dual CO2 sequestration by immobilizing photosynthetic microorganisms within a printable polymeric network. The carbon concentrating mechanism of the cyanobacteria enabled accumulation of CO2 within the cell, resulting in biomass production. Additionally, the metabolic production of OH- ions in the surrounding medium created an environment for the formation of insoluble carbonates via microbially-induced calcium carbonate precipitation (MICP). Digital design and fabrication of the living material ensured sufficient access to light and nutrient transport of the encapsulated cyanobacteria, which were essential for long-term viability (more than one year) as well as efficient photosynthesis and carbon sequestration. The photosynthetic living materials sequestered approximately 2.5 mg of CO2 per gram of hydrogel material over 30 days via dual carbon sequestration, with 2.2 ± 0.9 mg stored as insoluble carbonates. Over an extended incubation period of 400 days, the living materials sequestered 26 ± 7 mg of CO2 per gram of hydrogel material in the form of stable minerals. These findings highlight the potential of photosynthetic living materials for scalable carbon sequestration, carbon-neutral infrastructure, and green building materials. The simplicity of maintenance, coupled with its scalability nature, suggests broad applications of photosynthetic living materials as a complementary strategy to mitigate CO2 emissions.
Collapse
Affiliation(s)
- Dalia Dranseike
- Macromolecular Engineering Laboratory, Department of Mechanical and Process Engineering, ETH Zurich, Zurich, CH
| | - Yifan Cui
- Macromolecular Engineering Laboratory, Department of Mechanical and Process Engineering, ETH Zurich, Zurich, CH
| | - Andrea S. Ling
- Digital Building Technologies, Department of Architecture, ETH Zurich, Zurich, CH
| | - Felix Donat
- Laboratory of Energy Science and Engineering, Department of Mechanical and Process Engineering, ETH Zurich, Zurich, CH
| | - Stéphane Bernhard
- Macromolecular Engineering Laboratory, Department of Mechanical and Process Engineering, ETH Zurich, Zurich, CH
| | - Margherita Bernero
- Institute for Biomechanics, Department of Health Sciences and Technology, ETH Zurich, Zurich, CH
| | - Akhil Areeckal
- Macromolecular Engineering Laboratory, Department of Mechanical and Process Engineering, ETH Zurich, Zurich, CH
| | - Xiao-Hua Qin
- Institute for Biomechanics, Department of Health Sciences and Technology, ETH Zurich, Zurich, CH
| | - John S. Oakey
- Department of Chemical and Biomedical Engineering, University of Wyoming, Laramie, Wyoming, US
| | | | - André R. Studart
- Complex Materials, Department of Materials, ETH Zurich, Zurich, CH
| | - Mark W. Tibbitt
- Macromolecular Engineering Laboratory, Department of Mechanical and Process Engineering, ETH Zurich, Zurich, CH
| |
Collapse
|
8
|
Qian M, Han X, Liu J, Xu P, Tao F. Genomic Insights on the Carbon-Negative Workhorse: Systematical Comparative Genomic Analysis on 56 Synechococcus Strains. Bioengineering (Basel) 2023; 10:1329. [PMID: 38002453 PMCID: PMC10669429 DOI: 10.3390/bioengineering10111329] [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: 09/30/2023] [Revised: 10/31/2023] [Accepted: 11/09/2023] [Indexed: 11/26/2023] Open
Abstract
Synechococcus, a type of ancient photosynthetic cyanobacteria, is crucial in modern carbon-negative synthetic biology due to its potential for producing bioenergy and high-value products. With its high biomass, fast growth rate, and established genetic manipulation tools, Synechococcus has become a research focus in recent years. Abundant germplasm resources have been accumulated from various habitats, including temperature and salinity conditions relevant to industrialization. In this study, a comprehensive analysis of complete genomes of the 56 Synechococcus strains currently available in public databases was performed, clarifying genetic relationships, the adaptability of Synechococcus to the environment, and its reflection at the genomic level. This was carried out via pan-genome analysis and a detailed comparison of the functional gene groups. The results revealed an open-genome pattern, with 275 core genes and variable genome sizes within these strains. The KEGG annotation and orthology composition comparisons unveiled that the cold and thermophile strains have 32 and 84 unique KO functional units in their shared core gene functional units, respectively. Each KO functional unit reflects unique gene families and pathways. In terms of salt tolerance and comparative genomics, there are 65 unique KO functional units in freshwater-adapted strains and 154 in strictly marine strains. By delving into these aspects, our understanding of the metabolic potential of Synechococcus was deepened, promoting the development and industrial application of cyanobacterial biotechnology.
Collapse
Affiliation(s)
| | | | | | | | - Fei Tao
- School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China; (M.Q.); (X.H.); (J.L.); (P.X.)
| |
Collapse
|
9
|
Krings S, Chen Y, Keddie JL, Hingley-Wilson S. Oxygen evolution from extremophilic cyanobacteria confined in hard biocoatings. Microbiol Spectr 2023; 11:e0187023. [PMID: 37747195 PMCID: PMC10580922 DOI: 10.1128/spectrum.01870-23] [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: 05/05/2023] [Accepted: 08/04/2023] [Indexed: 09/26/2023] Open
Abstract
Biocoatings, in which viable bacteria are immobilized within a waterborne polymer coating for a wide range of potential applications, have garnered greater interest in recent years. In bioreactors, biocoatings can be ready-to-use alternatives for carbon capture or biofuel production that could be reused multiple times. Here, we have immobilized cyanobacteria in mechanically hard biocoatings, which were deposited from polymer colloids in water (i.e., latex). The biocoatings are formed upon heating to 37°C and fully dried before rehydrating. The viability and oxygen evolution of three cyanobacterial species within the biocoatings were compared. Synechococcus sp. PCC 7002 was non-viable inside the biocoatings immediately after drying, whereas Synechocystis sp. PCC 6803 survived the coating formation, as shown by an adenosine triphosphate (ATP) assay. Synechocystis sp. PCC 6803 consumed oxygen (by cell respiration) for up to 5 days, but was unable to perform photosynthesis, as indicated by a lack of oxygen evolution. However, Chroococcidiopsis cubana PCC 7433, a strain of desiccation-resistant extremophilic cyanobacteria, survived and performed photosynthesis and carbon capture within the biocoating, with specific rates of oxygen evolution up to 0.4 g of oxygen/g of biomass per day. Continuous measurements of dissolved oxygen were carried out over a month and showed no sign of decreasing activity. Extremophilic cyanobacteria are viable in a variety of environments, making them ideal candidates for use in biocoatings and other biotechnology. IMPORTANCE As water has become a precious resource, there is a growing need for less water-intensive use of microorganisms, while avoiding desiccation stress. Mechanically robust, ready-to-use biocoatings or "living paints" (a type of artificial biofilm consisting of a synthetic matrix containing functional bacteria) represent a novel way to address these issues. Here, we describe the revolutionary, first-ever use of an extremophilic cyanobacterium (Chroococcidiopsis cubana PCC 7433) in biocoatings, which were able to produce high levels of oxygen and carbon capture for at least 1 month despite complete desiccation and subsequent rehydration. Beyond culturing viable bacteria with reduced water resources, this pioneering use of extremophiles in biocoatings could be further developed for a variety of applications, including carbon capture, wastewater treatment and biofuel production.
Collapse
Affiliation(s)
- Simone Krings
- Department of Microbial Sciences, School of Biosciences, University of Surrey, Guildford, Surrey, United Kingdom
| | - Yuxiu Chen
- School of Mathematics and Physics, University of Surrey, Guildford, Surrey, United Kingdom
| | - Joseph L. Keddie
- School of Mathematics and Physics, University of Surrey, Guildford, Surrey, United Kingdom
| | - Suzanne Hingley-Wilson
- Department of Microbial Sciences, School of Biosciences, University of Surrey, Guildford, Surrey, United Kingdom
| |
Collapse
|
10
|
Li S, Guo W, Zeng M, Wu H. Safety assessment of Synechococcus sp. PCC 7002 biomass: genotoxicity, acute and subchronic toxicity studies. Food Funct 2023; 14:8008-8017. [PMID: 37593798 DOI: 10.1039/d3fo01692g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/19/2023]
Abstract
Synechococcus sp. PCC 7002 has the potential to be used as a new resource of food owing to its nutritional and functional benefits. However, little information has been published regarding the safety of Synechococcus sp. PCC 7002 biomass (SynB). The present study assessed genotoxicity, acute and subchronic toxicity of SynB for the first time. SynB did not show any genotoxicity based on the Ames test, mammalian erythrocyte micronucleus test, and mouse primary spermatocyte chromosome aberration test. SynB administered by gavage in mice at a dose of 10 g per kg body weight did not induce death or toxicity based on the acute toxicity study, indicating the median lethal dose value of SynB was over 10 g per kg body weight. In the 90-day subchronic toxicity study, no treatment-related mortality or clinical sign was noted with SynB at doses of 5 and 10 g per kg body weight in mice, and there was no adverse effect of SynB on food consumption, organ coefficients, blood biochemistry, urinalysis and histopathology. The Non Observed Adverse Effect Level for SynB in female and male mice was not less than 10 g per kg body weight per day based on subchronic toxicity. These results support the safe use of SynB as a new food raw material.
Collapse
Affiliation(s)
- Shiyang Li
- College of Food Science and Engineering, Ocean University of China, 5 Yushan Road, Qingdao, Shandong, 266003, China.
| | - Wei Guo
- School of Pharmacy, Binzhou Medical University, 346 Guanhai Road, Yantai, Shandong, 264003, China
| | - Mingyong Zeng
- College of Food Science and Engineering, Ocean University of China, 5 Yushan Road, Qingdao, Shandong, 266003, China.
| | - Haohao Wu
- College of Food Science and Engineering, Ocean University of China, 5 Yushan Road, Qingdao, Shandong, 266003, China.
| |
Collapse
|
11
|
Madhu S, Sengupta A, Sarnaik AP, Sahasrabuddhe D, Wangikar PP. Global Transcriptome-Guided Identification of Neutral Sites for Engineering Synechococcus elongatus PCC 11801. ACS Synth Biol 2023; 12:1677-1685. [PMID: 37252895 DOI: 10.1021/acssynbio.3c00019] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Engineered cyanobacteria are attractive hosts for the phototrophic conversion of CO2 to chemicals. Synechococcus elongatus PCC11801, a novel, fast-growing, and stress-tolerant cyanobacterium, has the potential to be a platform cell factory, and hence, it necessitates the development of a synthetic biology toolbox. Considering the widely followed cyanobacterial engineering strategy of chromosomal integration of heterologous DNA, it is of interest to discover and validate new chromosomal neutral sites (NSs) in this strain. To that end, global transcriptome analysis was performed using RNA Seq under the conditions of high temperature (HT), carbon (HC), and salt (HS) and ambient growth conditions. We found upregulation of 445, 138, and 87 genes and downregulation of 333, 125, and 132 genes, under HC, HT, and HS, respectively. Following nonhierarchical clustering, gene enrichment, and bioinformatics analysis, 27 putative NSs were predicted. Six of them were experimentally tested, and five showed confirmed neutrality, based on unaltered cell growth. Thus, global transcriptomic analysis was effectively exploited for NS annotation and would be advantageous for multiplexed genome editing.
Collapse
Affiliation(s)
- Swati Madhu
- Department of Chemical Engineering, Indian Institute of Technology Bombay, Powai, Mumbai 400076 India
| | - Annesha Sengupta
- Department of Chemical Engineering, Indian Institute of Technology Bombay, Powai, Mumbai 400076 India
| | - Aditya P Sarnaik
- Department of Chemical Engineering, Indian Institute of Technology Bombay, Powai, Mumbai 400076 India
| | - Deepti Sahasrabuddhe
- Department of Chemical Engineering, Indian Institute of Technology Bombay, Powai, Mumbai 400076 India
| | - Pramod P Wangikar
- Department of Chemical Engineering, Indian Institute of Technology Bombay, Powai, Mumbai 400076 India
| |
Collapse
|
12
|
Dallo T, Krishnakumar R, Kolker SD, Ruffing AM. High-Density Guide RNA Tiling and Machine Learning for Designing CRISPR Interference in Synechococcus sp. PCC 7002. ACS Synth Biol 2023; 12:1175-1186. [PMID: 36893454 DOI: 10.1021/acssynbio.2c00653] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/11/2023]
Abstract
While CRISPRi was previously established in Synechococcus sp. PCC 7002 (hereafter 7002), the design principles for guide RNA (gRNA) effectiveness remain largely unknown. Here, 76 strains of 7002 were constructed with gRNAs targeting three reporter systems to evaluate features that impact gRNA efficiency. Correlation analysis of the data revealed that important features of gRNA design include the position relative to the start codon, GC content, protospacer adjacent motif (PAM) site, minimum free energy, and targeted DNA strand. Unexpectedly, some gRNAs targeting upstream of the promoter region showed small but significant increases in reporter expression, and gRNAs targeting the terminator region showed greater repression than gRNAs targeting the 3' end of the coding sequence. Machine learning algorithms enabled prediction of gRNA effectiveness, with Random Forest having the best performance across all training sets. This study demonstrates that high-density gRNA data and machine learning can improve gRNA design for tuning gene expression in 7002.
Collapse
Affiliation(s)
- Tessa Dallo
- Molecular and Microbiology, Sandia National Laboratories, P.O. Box 5800, MS 1413, Albuquerque, New Mexico 87185, United States
| | - Raga Krishnakumar
- Systems Biology, Sandia National Laboratories, P.O. Box 969, MS 9292, Livermore, California 94551, United States
| | - Stephanie D Kolker
- Molecular and Microbiology, Sandia National Laboratories, P.O. Box 5800, MS 1413, Albuquerque, New Mexico 87185, United States
| | - Anne M Ruffing
- Molecular and Microbiology, Sandia National Laboratories, P.O. Box 5800, MS 1413, Albuquerque, New Mexico 87185, United States
| |
Collapse
|
13
|
Satta A, Esquirol L, Ebert BE. Current Metabolic Engineering Strategies for Photosynthetic Bioproduction in Cyanobacteria. Microorganisms 2023; 11:455. [PMID: 36838420 PMCID: PMC9964548 DOI: 10.3390/microorganisms11020455] [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: 12/12/2022] [Revised: 02/04/2023] [Accepted: 02/09/2023] [Indexed: 02/16/2023] Open
Abstract
Cyanobacteria are photosynthetic microorganisms capable of using solar energy to convert CO2 and H2O into O2 and energy-rich organic compounds, thus enabling sustainable production of a wide range of bio-products. More and more strains of cyanobacteria are identified that show great promise as cell platforms for the generation of bioproducts. However, strain development is still required to optimize their biosynthesis and increase titers for industrial applications. This review describes the most well-known, newest and most promising strains available to the community and gives an overview of current cyanobacterial biotechnology and the latest innovative strategies used for engineering cyanobacteria. We summarize advanced synthetic biology tools for modulating gene expression and their use in metabolic pathway engineering to increase the production of value-added compounds, such as terpenoids, fatty acids and sugars, to provide a go-to source for scientists starting research in cyanobacterial metabolic engineering.
Collapse
Affiliation(s)
- Alessandro Satta
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St Lucia, QLD 4072, Australia
- Department of Biology, University of Padua, 35100 Padua, Italy
| | - Lygie Esquirol
- Centre for Cell Factories and Biopolymers, Griffith Institute for Drug Discovery, Griffith University, Natha, QLD 4111, Australia
| | - Birgitta E. Ebert
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St Lucia, QLD 4072, Australia
| |
Collapse
|
14
|
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.
Collapse
|
15
|
Bourgade B, Stensjö K. Synthetic biology in marine cyanobacteria: Advances and challenges. Front Microbiol 2022; 13:994365. [PMID: 36188008 PMCID: PMC9522894 DOI: 10.3389/fmicb.2022.994365] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Accepted: 08/24/2022] [Indexed: 11/19/2022] Open
Abstract
The current economic and environmental context requests an accelerating development of sustainable alternatives for the production of various target compounds. Biological processes offer viable solutions and have gained renewed interest in the recent years. For example, photosynthetic chassis organisms are particularly promising for bioprocesses, as they do not require biomass-derived carbon sources and contribute to atmospheric CO2 fixation, therefore supporting climate change mitigation. Marine cyanobacteria are of particular interest for biotechnology applications, thanks to their rich diversity, their robustness to environmental changes, and their metabolic capabilities with potential for therapeutics and chemicals production without requiring freshwater. The additional cyanobacterial properties, such as efficient photosynthesis, are also highly beneficial for biotechnological processes. Due to their capabilities, research efforts have developed several genetic tools for direct metabolic engineering applications. While progress toward a robust genetic toolkit is continuously achieved, further work is still needed to routinely modify these species and unlock their full potential for industrial applications. In contrast to the understudied marine cyanobacteria, genetic engineering and synthetic biology in freshwater cyanobacteria are currently more advanced with a variety of tools already optimized. This mini-review will explore the opportunities provided by marine cyanobacteria for a greener future. A short discussion will cover the advances and challenges regarding genetic engineering and synthetic biology in marine cyanobacteria, followed by a parallel with freshwater cyanobacteria and their current genetic availability to guide the prospect for marine species.
Collapse
Affiliation(s)
- Barbara Bourgade
- Microbial Chemistry, Department of Chemistry-Ångström Laboratory, Uppsala University, Uppsala, Sweden
| | - Karin Stensjö
- Microbial Chemistry, Department of Chemistry-Ångström Laboratory, Uppsala University, Uppsala, Sweden
| |
Collapse
|
16
|
Peng W, Bao Q, Jia R, He P. Construction of an easily detectable transgenic Synechococcus elongatus PCC 7942 against White Spot Syndrome Virus using vp28 and mOrange Gene and its metabolism in shrimp. Front Immunol 2022; 13:974014. [PMID: 36091009 PMCID: PMC9459150 DOI: 10.3389/fimmu.2022.974014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Accepted: 08/01/2022] [Indexed: 11/29/2022] Open
Abstract
White spot syndrome is an epidemic disease caused by the highly contagious and lethal white spot syndrome virus (WSSV), resulting in huge economic losses to the global aquaculture industry. VP28 is the main structural protein in the capsule of WSSV and is important in the early stage of infection. Under an excitation wavelength of 548 nm, the mOrange fluorescent protein releases a 562 nm emission wavelength, which is different from the autofluorescence of cyanobacteria. Therefore, using this characteristic combined with the receptor system of Synechococcus elongatus PCC 7942, we constructed transgenic S. elongatus to express the recombinant protein VP28-mOrange. In addition, PCR and western blotting were used to confirm the stable expression of the target gene in cyanobacteria. Using mOrange tracer features, we explored the recombinant protein VP28-mOrange in the metabolic cycle of young Litopenaeus Vannamei after feeding. After the young shrimp had stopped consuming transgenic cyanobacteria, the 24 to 33 h fluorescence signal in the intestine was very weak, and almost disappeared after 36 h. We explored the protective effect of transgenic vp28-mOrange S. elongatus within 48 h of being ingested by L. vannamei and set WSSV challenges at 2, 12, 24, and 48 h post-immunization. However, the survival rate of L. vannamei decreased as the time of the WSSV challenge increased. The survival rate on the seventh day was 81%, 52%, 45.5%, and 33.3% for shrimps challenged for 2, 12, 24, and 48 h, respectively. Enzyme activity can also support this conjecture, the enzyme activity indexes of the experimental groups were significantly reduced compared to positive and wild-type controls. Therefore, this immune agent functioned as a preventive agent. Compared with the traditional method, this method was easy to detect and can visualize the digestion of transgenic cyanobacteria in the Litopenaeus vannamei intestine.
Collapse
Affiliation(s)
| | | | - Rui Jia
- *Correspondence: Rui Jia, ; Peimin He,
| | - Peimin He
- *Correspondence: Rui Jia, ; Peimin He,
| |
Collapse
|
17
|
Simple transformation of the filamentous thermophilic cyanobacterium Leptolyngbya sp. KC45. ALGAL RES 2022. [DOI: 10.1016/j.algal.2022.102758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
18
|
Andrews F, Faulkner M, Toogood HS, Scrutton NS. Combinatorial use of environmental stresses and genetic engineering to increase ethanol titres in cyanobacteria. BIOTECHNOLOGY FOR BIOFUELS 2021; 14:240. [PMID: 34920731 PMCID: PMC8684110 DOI: 10.1186/s13068-021-02091-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Accepted: 12/05/2021] [Indexed: 06/07/2023]
Abstract
Current industrial bioethanol production by yeast through fermentation generates carbon dioxide. Carbon neutral bioethanol production by cyanobacteria uses biological fixation (photosynthesis) of carbon dioxide or other waste inorganic carbon sources, whilst being sustainable and renewable. The first ethanologenic cyanobacterial process was developed over two decades ago using Synechococcus elongatus PCC 7942, by incorporating the recombinant pdc and adh genes from Zymomonas mobilis. Further engineering has increased bioethanol titres 24-fold, yet current levels are far below what is required for industrial application. At the heart of the problem is that the rate of carbon fixation cannot be drastically accelerated and carbon partitioning towards bioethanol production impacts on cell fitness. Key progress has been achieved by increasing the precursor pyruvate levels intracellularly, upregulating synthetic genes and knocking out pathways competing for pyruvate. Studies have shown that cyanobacteria accumulate high proportions of carbon reserves that are mobilised under specific environmental stresses or through pathway engineering to increase ethanol production. When used in conjunction with specific genetic knockouts, they supply significantly more carbon for ethanol production. This review will discuss the progress in generating ethanologenic cyanobacteria through chassis engineering, and exploring the impact of environmental stresses on increasing carbon flux towards ethanol production.
Collapse
Affiliation(s)
- Fraser Andrews
- EPSRC/BBSRC Future Biomanufacturing Research Hub, BBSRC/EPSRC Synthetic Biology Research Centre SYNBIOCHEM Manchester Institute of Biotechnology and School of Chemistry, The University of Manchester, Manchester, M1 7DN, UK
| | - Matthew Faulkner
- EPSRC/BBSRC Future Biomanufacturing Research Hub, BBSRC/EPSRC Synthetic Biology Research Centre SYNBIOCHEM Manchester Institute of Biotechnology and School of Chemistry, The University of Manchester, Manchester, M1 7DN, UK
| | - Helen S Toogood
- EPSRC/BBSRC Future Biomanufacturing Research Hub, BBSRC/EPSRC Synthetic Biology Research Centre SYNBIOCHEM Manchester Institute of Biotechnology and School of Chemistry, The University of Manchester, Manchester, M1 7DN, UK
| | - Nigel S Scrutton
- EPSRC/BBSRC Future Biomanufacturing Research Hub, BBSRC/EPSRC Synthetic Biology Research Centre SYNBIOCHEM Manchester Institute of Biotechnology and School of Chemistry, The University of Manchester, Manchester, M1 7DN, UK.
- C3 Biotechnologies Ltd, 20 Mannin Way, Lancaster Business Park, Caton Road, Lancaster, LA1 3SW, Lancashire, UK.
| |
Collapse
|
19
|
Juteršek M, Dolinar M. A chimeric vector for dual use in cyanobacteria and Escherichia coli, tested with cystatin, a nonfluorescent reporter protein. PeerJ 2021; 9:e12199. [PMID: 34760347 PMCID: PMC8571960 DOI: 10.7717/peerj.12199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Accepted: 09/01/2021] [Indexed: 11/23/2022] Open
Abstract
Background Developing sustainable autotrophic cell factories depends heavily on the availability of robust and well-characterized biological parts. For cyanobacteria, these still lag behind the more advanced E. coli toolkit. In the course of previous protein expression experiments with cyanobacteria, we encountered inconveniences in working with currently available RSF1010-based shuttle plasmids, particularly due to their low biosafety and low yields of recombinant proteins. We also recognized some drawbacks of the commonly used fluorescent reporters, as quantification can be affected by the intrinsic fluorescence of cyanobacteria. To overcome these drawbacks, we envisioned a new chimeric vector and an alternative reporter that could be used in cyanobacterial synthetic biology and tested them in the model cyanobacterium Synechocystis sp. PCC 6803. Methods We designed the pMJc01 shuttle plasmid based on the broad host range RSFmob-I replicon. Standard cloning techniques were used for vector construction following the RFC10 synthetic biology standard. The behavior of pMJC01 was tested with selected regulatory elements in E. coli and Synechocystis sp. PCC 6803 for the biosynthesis of the established GFP reporter and of a new reporter protein, cystatin. Cystatin activity was assayed using papain as a cognate target. Results With the new vector we observed a significantly higher GFP expression in E. coli and Synechocystis sp. PCC 6803 compared to the commonly used RSF1010-based pPMQAK1. Cystatin, a cysteine protease inhibitor, was successfully expressed with the new vector in both E. coli and Synechocystis sp. PCC 6803. Its expression levels allowed quantification comparable to the standardly used fluorescent reporter GFPmut3b. An important advantage of the new vector is its improved biosafety due to the absence of plasmid regions encoding conjugative transfer components. The broadhost range vector pMJc01 could find application in synthetic biology and biotechnology of cyanobacteria due to its relatively small size, stability and ease of use. In addition, cystatin could be a useful reporter in all cell systems that do not contain papain-type proteases and inhibitors, such as cyanobacteria, and provides an alternative to fluorescent reporters or complements them.
Collapse
Affiliation(s)
- Mojca Juteršek
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, Ljubljana, Slovenia.,Current Affiliation: National Institute of Biology, Ljubljana, Slovenia
| | - Marko Dolinar
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, Ljubljana, Slovenia
| |
Collapse
|
20
|
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.
Collapse
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.
| |
Collapse
|
21
|
Chávez MN, Fuchs B, Moellhoff N, Hofmann D, Zhang L, Selão TT, Giunta RE, Egaña JT, Nickelsen J, Schenck TL. Use of photosynthetic transgenic cyanobacteria to promote lymphangiogenesis in scaffolds for dermal regeneration. Acta Biomater 2021; 126:132-143. [PMID: 33753313 DOI: 10.1016/j.actbio.2021.03.033] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Revised: 02/28/2021] [Accepted: 03/15/2021] [Indexed: 02/06/2023]
Abstract
Impaired wound healing represents an unsolved medical need with a high impact on patients´ quality of life and global health care. Even though its causes are diverse, ischemic-hypoxic conditions and exacerbated inflammation are shared pathological features responsible for obstructing tissue restoration. In line with this, it has been suggested that promoting a normoxic pro-regenerative environment and accelerating inflammation resolution, by reinstating the lymphatic fluid transport, could allow the wound healing process to be resumed. Our group was first to demonstrate the functional use of scaffolds seeded with photosynthetic microorganisms to supply tissues with oxygen. Moreover, we previously proposed a photosynthetic gene therapy strategy to create scaffolds that deliver other therapeutic molecules, such as recombinant human growth factors into the wound area. In the present work, we introduce the use of transgenic Synechococcus sp. PCC 7002 cyanobacteria (SynHA), which can produce oxygen and lymphangiogenic hyaluronic acid, in photosynthetic biomaterials. We show that the co-culture of lymphatic endothelial cells with SynHA promotes their survival and proliferation under hypoxic conditions. Also, hyaluronic acid secreted by the cyanobacteria enhanced their lymphangiogenic potential as shown by changes to their gene expression profile, the presence of lymphangiogenic protein markers and their capacity to build lymph vessel tubes. Finally, by seeding SynHA into collagen-based dermal regeneration materials, we developed a viable photosynthetic scaffold that promotes lymphangiogenesis in vitro under hypoxic conditions. The results obtained in this study lay the groundwork for future tissue engineering applications using transgenic cyanobacteria that could become a therapeutic alternative for chronic wound treatment. STATEMENT OF SIGNIFICANCE: In this study, we introduce the use of transgenic Synechococcus sp. PCC 7002 (SynHA) cyanobacteria, which were genetically engineered to produce hyaluronic acid, to create lymphangiogenic photosynthetic scaffolds for dermal regeneration. Our results confirmed that SynHA cyanobacteria maintain their photosynthetic capacity under standard human cell culture conditions and efficiently proliferate when seeded inside fibrin-collagen scaffolds. Moreover, we show that SynHA supported the viability of co-cultured lymphatic endothelial cells (LECs) under hypoxic conditions by providing them with photosynthetic-derived oxygen, while cyanobacteria-derived hyaluronic acid stimulated the lymphangiogenic capacity of LECs. Since tissue hypoxia and impaired lymphatic drainage are two key factors that directly affect wound healing, our results suggest that lymphangiogenic photosynthetic biomaterials could become a treatment option for chronic wound management.
Collapse
Affiliation(s)
- Myra N Chávez
- Molecular Plant Science, Department Biology I, LMU Munich, Munich, Germany
| | - Benedikt Fuchs
- Division of Hand, Plastic and Aesthetic Surgery, University Hospital, LMU Munich, Munich, Germany
| | - Nicholas Moellhoff
- Division of Hand, Plastic and Aesthetic Surgery, University Hospital, LMU Munich, Munich, Germany
| | - Daniel Hofmann
- Division of Hand, Plastic and Aesthetic Surgery, University Hospital, LMU Munich, Munich, Germany
| | - Lifang Zhang
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Tiago Toscano Selão
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Riccardo E Giunta
- Division of Hand, Plastic and Aesthetic Surgery, University Hospital, LMU Munich, Munich, Germany
| | - José Tomás Egaña
- Institute for Biological and Medical Engineering, Schools of Engineering, Biological Sciences and Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Jörg Nickelsen
- Molecular Plant Science, Department Biology I, LMU Munich, Munich, Germany; School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Thilo L Schenck
- Division of Hand, Plastic and Aesthetic Surgery, University Hospital, LMU Munich, Munich, Germany; Frauenklinik Dr. Geisenhofer, Munich, Germany.
| |
Collapse
|
22
|
Genetic, Genomics, and Responses to Stresses in Cyanobacteria: Biotechnological Implications. Genes (Basel) 2021; 12:genes12040500. [PMID: 33805386 PMCID: PMC8066212 DOI: 10.3390/genes12040500] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Revised: 03/25/2021] [Accepted: 03/25/2021] [Indexed: 02/07/2023] Open
Abstract
Cyanobacteria are widely-diverse, environmentally crucial photosynthetic prokaryotes of great interests for basic and applied science. Work to date has focused mostly on the three non-nitrogen fixing unicellular species Synechocystis PCC 6803, Synechococcus PCC 7942, and Synechococcus PCC 7002, which have been selected for their genetic and physiological interests summarized in this review. Extensive "omics" data sets have been generated, and genome-scale models (GSM) have been developed for the rational engineering of these cyanobacteria for biotechnological purposes. We presently discuss what should be done to improve our understanding of the genotype-phenotype relationships of these models and generate robust and predictive models of their metabolism. Furthermore, we also emphasize that because Synechocystis PCC 6803, Synechococcus PCC 7942, and Synechococcus PCC 7002 represent only a limited part of the wide biodiversity of cyanobacteria, other species distantly related to these three models, should be studied. Finally, we highlight the need to strengthen the communication between academic researchers, who know well cyanobacteria and can engineer them for biotechnological purposes, but have a limited access to large photobioreactors, and industrial partners who attempt to use natural or engineered cyanobacteria to produce interesting chemicals at reasonable costs, but may lack knowledge on cyanobacterial physiology and metabolism.
Collapse
|
23
|
Dahlgren KK, Gates C, Lee T, Cameron JC. Proximity-based proteomics reveals the thylakoid lumen proteome in the cyanobacterium Synechococcus sp. PCC 7002. PHOTOSYNTHESIS RESEARCH 2021; 147:177-195. [PMID: 33280076 PMCID: PMC7880944 DOI: 10.1007/s11120-020-00806-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Accepted: 11/23/2020] [Indexed: 06/12/2023]
Abstract
Cyanobacteria possess unique intracellular organization. Many proteomic studies have examined different features of cyanobacteria to learn about the intracellular structures and their respective functions. While these studies have made great progress in understanding cyanobacterial physiology, the conventional fractionation methods used to purify cellular structures have limitations; specifically, certain regions of cells cannot be purified with existing fractionation methods. Proximity-based proteomics techniques were developed to overcome the limitations of biochemical fractionation for proteomics. Proximity-based proteomics relies on spatiotemporal protein labeling followed by mass spectrometry of the labeled proteins to determine the proteome of the region of interest. We performed proximity-based proteomics in the cyanobacterium Synechococcus sp. PCC 7002 with the APEX2 enzyme, an engineered ascorbate peroxidase. We determined the proteome of the thylakoid lumen, a region of the cell that has remained challenging to study with existing methods, using a translational fusion between APEX2 and PsbU, a lumenal subunit of photosystem II. Our results demonstrate the power of APEX2 as a tool to study the cell biology of intracellular features and processes, including photosystem II assembly in cyanobacteria, with enhanced spatiotemporal resolution.
Collapse
Affiliation(s)
- Kelsey K Dahlgren
- Department of Biochemistry, University of Colorado, Boulder, CO, 80309, USA
- Renewable and Sustainable Energy Institute, University of Colorado, Boulder, CO, 80309, USA
- BioFrontiers Institute, University of Colorado, Boulder, CO, 80309, USA
- Interdisciplinary Quantitative Biology Program (IQ Biology), BioFrontiers Institute, University of Colorado, Boulder, CO, 80309, USA
| | - Colin Gates
- Renewable and Sustainable Energy Institute, University of Colorado, Boulder, CO, 80309, USA
| | - Thomas Lee
- Department of Biochemistry, University of Colorado, Boulder, CO, 80309, USA
| | - Jeffrey C Cameron
- Department of Biochemistry, University of Colorado, Boulder, CO, 80309, USA.
- Renewable and Sustainable Energy Institute, University of Colorado, Boulder, CO, 80309, USA.
- National Renewable Energy Laboratory, Golden, CO, 80401, USA.
| |
Collapse
|
24
|
Madsen MA, Hamilton G, Herzyk P, Amtmann A. Environmental Regulation of PndbA600, an Auto-Inducible Promoter for Two-Stage Industrial Biotechnology in Cyanobacteria. Front Bioeng Biotechnol 2021; 8:619055. [PMID: 33542914 PMCID: PMC7853294 DOI: 10.3389/fbioe.2020.619055] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Accepted: 12/09/2020] [Indexed: 11/13/2022] Open
Abstract
Cyanobacteria are photosynthetic prokaryotes being developed as sustainable platforms that use renewable resources (light, water, and air) for diverse applications in energy, food, environment, and medicine. Despite the attractive promise that cyanobacteria offer to industrial biotechnology, slow growth rates pose a major challenge in processes which typically require large amounts of biomass and are often toxic to the cells. Two-stage cultivation strategies are an attractive solution to prevent any undesired growth inhibition by de-coupling biomass accumulation (stage I) and the industrial process (stage II). In cyanobacteria, two-stage strategies involve costly transfer methods between stages I and II, and little work has been focussed on using the distinct growth and stationary phases of batch cultures to autoregulate stage transition. In the present study, we identified and characterised a growth phase-specific promoter, which can serve as an auto-inducible switch to regulate two-stage bioprocesses in cyanobacteria. First, growth phase-specific genes were identified from a new RNAseq dataset comparing two growth phases and six nutrient conditions in Synechocystis sp. PCC 6803, including two new transcriptomes for low Mg and low K. A type II NADH dehydrogenase (ndbA) showed robust induction when the cultures transitioned from exponential to stationary phase growth. Behaviour of a 600-bp promoter sequence (PndbA600) was then characterised in detail following the expression of PndbA600:GFP in Synechococcus sp. PCC 7002. Culture density and growth media analyses showed that PndbA600 activation was not dependent on increases in culture density per se but on N availability and on another activating factor present in the spent media of stationary phase cultures (Factor X). PndbA600 deactivation was dependent on the changes in culture density and in either N availability or Factor X. Electron transport inhibition studies revealed a photosynthesis-specific enhancement of active PndbA600 levels. Our findings are summarised in a model describing the environmental regulation of PndbA600, which can now inform the rational design of two-stage industrial processes in cyanobacteria.
Collapse
Affiliation(s)
- Mary Ann Madsen
- College of Medical, Veterinary and Life Sciences, Institute of Molecular, Cell and Systems Biology, University of Glasgow, Glasgow, United Kingdom
| | - Graham Hamilton
- Glasgow Polyomics, Wolfson Wohl Cancer Research Centre, University of Glasgow, Glasgow, United Kingdom
| | - Pawel Herzyk
- College of Medical, Veterinary and Life Sciences, Institute of Molecular, Cell and Systems Biology, University of Glasgow, Glasgow, United Kingdom.,Glasgow Polyomics, Wolfson Wohl Cancer Research Centre, University of Glasgow, Glasgow, United Kingdom
| | - Anna Amtmann
- College of Medical, Veterinary and Life Sciences, Institute of Molecular, Cell and Systems Biology, University of Glasgow, Glasgow, United Kingdom
| |
Collapse
|
25
|
Kato Y, Hasunuma T. Metabolic Engineering for Carotenoid Production Using Eukaryotic Microalgae and Prokaryotic Cyanobacteria. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1261:121-135. [PMID: 33783735 DOI: 10.1007/978-981-15-7360-6_10] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Eukaryotic microalgae and prokaryotic cyanobacteria are diverse photosynthetic organisms that produce various useful compounds. Due to their rapid growth and efficient biomass production from carbon dioxide and solar energy, microalgae and cyanobacteria are expected to become cost-effective, sustainable bioresources in the future. These organisms also abundantly produce various carotenoids, but further improvement in carotenoid productivity is needed for a successful commercialization. Metabolic engineering via genetic manipulation and mutational breeding is a powerful tool for generating carotenoid-rich strains. This chapter focuses on carotenoid production in microalgae and cyanobacteria, as well as strategies and potential target genes for metabolic engineering. Recent achievements in metabolic engineering that improved carotenoid production in microalgae and cyanobacteria are also reviewed.
Collapse
Affiliation(s)
- Yuichi Kato
- Graduate School of Science, Technology and Innovation, Kobe University, Kobe-city, Hyogo, Japan
| | - Tomohisa Hasunuma
- Graduate School of Science, Technology and Innovation, Kobe University, Kobe-city, Hyogo, Japan.
| |
Collapse
|
26
|
Vijayakumar S, Rahman PK, Angione C. A Hybrid Flux Balance Analysis and Machine Learning Pipeline Elucidates Metabolic Adaptation in Cyanobacteria. iScience 2020; 23:101818. [PMID: 33354660 PMCID: PMC7744713 DOI: 10.1016/j.isci.2020.101818] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Revised: 10/23/2020] [Accepted: 11/13/2020] [Indexed: 01/20/2023] Open
Abstract
Machine learning has recently emerged as a promising tool for inferring multi-omic relationships in biological systems. At the same time, genome-scale metabolic models (GSMMs) can be integrated with such multi-omic data to refine phenotypic predictions. In this work, we use a multi-omic machine learning pipeline to analyze a GSMM of Synechococcus sp. PCC 7002, a cyanobacterium with large potential to produce renewable biofuels. We use regularized flux balance analysis to observe flux response between conditions across photosynthesis and energy metabolism. We then incorporate principal-component analysis, k-means clustering, and LASSO regularization to reduce dimensionality and extract key cross-omic features. Our results suggest that combining metabolic modeling with machine learning elucidates mechanisms used by cyanobacteria to cope with fluctuations in light intensity and salinity that cannot be detected using transcriptomics alone. Furthermore, GSMMs introduce critical mechanistic details that improve the performance of omic-based machine learning methods.
Collapse
Affiliation(s)
- Supreeta Vijayakumar
- Department of Computer Science and Information Systems, Teesside University, Middlesbrough, North Yorkshire TS1 3BX, UK
| | - Pattanathu K.S.M. Rahman
- Centre for Enzyme Innovation, Institute of Biological and Biomedical Sciences, School of Biological Sciences, University of Portsmouth, Portsmouth, Hampshire PO1 2UP, UK
- Tara Biologics, Woking, Surrey GU21 6BP, UK
| | - Claudio Angione
- Department of Computer Science and Information Systems, Teesside University, Middlesbrough, North Yorkshire TS1 3BX, UK
- Centre for Digital Innovation, Teesside University, Middlesbrough TS1 3BX, UK
- Healthcare Innovation Centre, Teesside University, Middlesbrough TS1 3BX, UK
| |
Collapse
|
27
|
Hunnestad AV, Vogel AIM, Armstrong E, Digernes MG, Ardelan MV, Hohmann-Marriott MF. From the Ocean to the Lab-Assessing Iron Limitation in Cyanobacteria: An Interface Paper. Microorganisms 2020; 8:E1889. [PMID: 33260337 PMCID: PMC7760322 DOI: 10.3390/microorganisms8121889] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 11/25/2020] [Accepted: 11/26/2020] [Indexed: 12/22/2022] Open
Abstract
Iron is an essential, yet scarce, nutrient in marine environments. Phytoplankton, and especially cyanobacteria, have developed a wide range of mechanisms to acquire iron and maintain their iron-rich photosynthetic machinery. Iron limitation studies often utilize either oceanographic methods to understand large scale processes, or laboratory-based, molecular experiments to identify underlying molecular mechanisms on a cellular level. Here, we aim to highlight the benefits of both approaches to encourage interdisciplinary understanding of the effects of iron limitation on cyanobacteria with a focus on avoiding pitfalls in the initial phases of collaboration. In particular, we discuss the use of trace metal clean methods in combination with sterile techniques, and the challenges faced when a new collaboration is set up to combine interdisciplinary techniques. Methods necessary for producing reliable data, such as High Resolution Inductively Coupled Plasma Mass Spectrometry (HR-ICP-MS), Flow Injection Analysis Chemiluminescence (FIA-CL), and 77K fluorescence emission spectroscopy are discussed and evaluated and a technical manual, including the preparation of the artificial seawater medium Aquil, cleaning procedures, and a sampling scheme for an iron limitation experiment is included. This paper provides a reference point for researchers to implement different techniques into interdisciplinary iron studies that span cyanobacteria physiology, molecular biology, and biogeochemistry.
Collapse
Affiliation(s)
- Annie Vera Hunnestad
- Department of Chemistry, Norwegian University of Science and Technology (NTNU), 7491 Trondheim, Norway; (A.V.H.); (M.G.D.)
| | - Anne Ilse Maria Vogel
- PhotoSynLab, Department of Biotechnology and Food Science, Norwegian University of Science and Technology (NTNU), 7491 Trondheim, Norway; (A.I.M.V.); (M.F.H.-M.)
| | - Evelyn Armstrong
- NIWA/University of Otago Research Centre for Oceanography, Department of Chemistry, University of Otago, 9054 Dunedin, New Zealand;
| | - Maria Guadalupe Digernes
- Department of Chemistry, Norwegian University of Science and Technology (NTNU), 7491 Trondheim, Norway; (A.V.H.); (M.G.D.)
| | - Murat Van Ardelan
- Department of Chemistry, Norwegian University of Science and Technology (NTNU), 7491 Trondheim, Norway; (A.V.H.); (M.G.D.)
| | - Martin Frank Hohmann-Marriott
- PhotoSynLab, Department of Biotechnology and Food Science, Norwegian University of Science and Technology (NTNU), 7491 Trondheim, Norway; (A.I.M.V.); (M.F.H.-M.)
| |
Collapse
|
28
|
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]
|
29
|
Engineering of Synechococcus sp. strain PCC 7002 for the photoautotrophic production of light-sensitive riboflavin (vitamin B2). Metab Eng 2020; 62:275-286. [DOI: 10.1016/j.ymben.2020.09.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 09/09/2020] [Accepted: 09/19/2020] [Indexed: 11/24/2022]
|
30
|
Wang F, Gao Y, Yang G. Recent advances in synthetic biology of cyanobacteria for improved chemicals production. Bioengineered 2020; 11:1208-1220. [PMID: 33124500 PMCID: PMC8291842 DOI: 10.1080/21655979.2020.1837458] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Cyanobacteria are Gram-negative photoautotrophic prokaryotes and have shown great importance to the Earth’s ecology. Based on their capability in oxygenic photosynthesis and genetic merits, they can be engineered as microbial chassis for direct conversion of carbon dioxide to value-added biofuels and chemicals. In the last decades, attempts have given to the application of synthetic biology tools and approaches in the development of cyanobacterial cell factories. Despite the successful proof-of-principle studies, large-scale application is still a technical challenge due to low yields of bioproducts. Therefore, recent efforts are underway to characterize and develop genetic regulatory parts and strategies for the synthetic biology applications in cyanobacteria. In this review, we present the recent advancements and application in cyanobacterial synthetic biology toolboxes. We also discuss the limitations and future perspectives for using such novel tools in cyanobacterial biotechnology.
Collapse
Affiliation(s)
- Fen Wang
- Department of Surgery, College of Medicine, University of Florida , Gainesville, FL, USA
| | - Yuanyuan Gao
- Jining Academy of Agricultural Science , Jining, Shandong, China
| | - Guang Yang
- Department of Aging and Geriatric Research, Institute on Aging, University of Florida , Gainesville, FL, USA
| |
Collapse
|
31
|
Chávez MN, Moellhoff N, Schenck TL, Egaña JT, Nickelsen J. Photosymbiosis for Biomedical Applications. Front Bioeng Biotechnol 2020; 8:577204. [PMID: 33123516 PMCID: PMC7573207 DOI: 10.3389/fbioe.2020.577204] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2020] [Accepted: 09/10/2020] [Indexed: 12/17/2022] Open
Abstract
Without the sustained provision of adequate levels of oxygen by the cardiovascular system, the tissues of higher animals are incapable of maintaining normal metabolic activity, and hence cannot survive. The consequence of this evolutionarily suboptimal design is that humans are dependent on cardiovascular perfusion, and therefore highly susceptible to alterations in its normal function. However, hope may be at hand. “Photosynthetic strategies,” based on the recognition that photosynthesis is the source of all oxygen, offer a revolutionary and promising solution to pathologies related to tissue hypoxia. These approaches, which have been under development over the past 20 years, seek to harness photosynthetic microorganisms as a local and controllable source of oxygen to circumvent the need for blood perfusion to sustain tissue survival. To date, their applications extend from the in vitro creation of artificial human tissues to the photosynthetic maintenance of oxygen-deprived organs both in vivo and ex vivo, while their potential use in other medical approaches has just begun to be explored. This review provides an overview of the state of the art of photosynthetic technologies and its innovative applications, as well as an expert assessment of the major challenges and how they can be addressed.
Collapse
Affiliation(s)
- Myra N Chávez
- Molecular Plant Science, Department Biology I, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Nicholas Moellhoff
- Division of Hand, Plastic and Aesthetic Surgery, University Hospital, Ludwig Maximilian Universität München, Munich, Germany
| | - Thilo L Schenck
- Division of Hand, Plastic and Aesthetic Surgery, University Hospital, Ludwig Maximilian Universität München, Munich, Germany
| | - José Tomás Egaña
- Institute for Biological and Medical Engineering, Schools of Engineering, Biological Sciences and Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Jörg Nickelsen
- Molecular Plant Science, Department Biology I, Ludwig-Maximilians-Universität München, Munich, Germany
| |
Collapse
|
32
|
Morphological plasticity of hyperelongated cells caused by overexpression of translation elongation factor P in Synechococcus elongatus PCC7942. Appl Microbiol Biotechnol 2020; 104:8801-8812. [PMID: 32915258 DOI: 10.1007/s00253-020-10874-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Revised: 08/17/2020] [Accepted: 08/31/2020] [Indexed: 10/23/2022]
Abstract
Translation elongation factors (EFs) are proteins that play important roles during the elongation stage of protein synthesis. In prokaryotes, at least four EFs function in repetitive reactions (EF-Tu, EF-Ts, EF-G, and EF-P). EF-P plays a vital role in the specialized translation of consecutive proline amino acid motifs. It was also recently recognized that EF-P acts throughout translation elongation. Here, we demonstrated for the first time that cell division and morphology are intimately linked to the control of EF-P in the model cyanobacterium Synechococcus elongatus PCC7942. We constructed the overexpression of a wild-type gene product for EF-P (Synpcc7942_2565) as a tool to identify EF-P functionality. The overexpression of EF-P resulted in the morphological plasticity of hyperelongated cells. During the stationary phase, EF-P overexpressors displayed cell lengths of 150 μm or longer, approximately 35 times longer than the control. Total cellular protein and amino acid content were also increased in overexpressors. To explore the molecular mechanisms underlying hyperelongation, gene expression analysis was performed. The results revealed that cell division genes, including ftn6, minD, mreB, mreC, and ftsZ, were modulated in overexpressors. Strikingly, ftn6 was severely down-regulated. Little is known regarding EF-P in prokaryotic photosynthetic organisms. Our results suggest that cyanobacterial EF-P participates in the acceleration of protein synthesis and also regulates cell division processes. These findings suggest new ways to modify translation and metabolism in cyanobacteria. Phenotypic and metabolic alterations caused by overexpressing EF-P may also be beneficial for applications such as low-cost, green molecular factories. KEY POINTS: • Cell division and cell morphology in the cyanobacterium Synechococcus elongatus PCC7942 are closely linked with the control of translation elongation factor P (EF-P). • Overexpression of EF-P leads to morphological plasticity in hyperelongated cells. • Cyanobacterial EF-P is involved in the acceleration of protein synthesis and the regulation of cell division processes.
Collapse
|
33
|
Abstract
RNA degradation is an important process that affects the final concentration of individual mRNAs, affecting protein expression and cellular physiology. Studies of how RNA is degraded increase our knowledge of this fundamental process as well as enable the creation of genetic tools to manipulate RNA stability. By studying global transcript turnover, we searched for sequence elements that correlated with transcript (in)stability and used these sequences to guide tool design. This study probes global RNA turnover in a cyanobacterium, Synechococcus sp. strain PCC 7002, that both has a unique array of RNases that facilitate RNA degradation and is an industrially relevant strain that could be used to convert CO2 and sunlight into useful products. RNA degradation is an important process that influences the ultimate concentration of individual proteins inside cells. While the main enzymes that facilitate this process have been identified, global maps of RNA turnover are available for only a few species. Even in these cases, there are few sequence elements that are known to enhance or destabilize a native transcript; even fewer confer the same effect when added to a heterologous transcript. To address this knowledge gap, we assayed genome-wide RNA degradation in the cyanobacterium Synechococcus sp. strain PCC 7002 by collecting total RNA samples after stopping nascent transcription with rifampin. We quantified the abundance of each position in the transcriptome as a function of time using RNA-sequencing data and later analyzed the global mRNA decay map using machine learning principles. Half-lives, calculated on a per-ORF (open reading frame) basis, were extremely short, with a median half-life of only 0.97 min. Despite extremely rapid turnover of most mRNA, transcripts encoding proteins involved in photosynthesis were both highly expressed and highly stable. Upon inspection of these stable transcripts, we identified an enriched motif in the 3′ untranslated region (UTR) that had similarity to Rho-independent terminators. We built statistical models for half-life prediction and used them to systematically identify sequence motifs in both 5′ and 3′ UTRs that correlate with stabilized transcripts. We found that transcripts linked to a terminator containing a poly(U) tract had a longer half-life than both those without a poly(U) tract and those without a terminator. IMPORTANCE RNA degradation is an important process that affects the final concentration of individual mRNAs, affecting protein expression and cellular physiology. Studies of how RNA is degraded increase our knowledge of this fundamental process as well as enable the creation of genetic tools to manipulate RNA stability. By studying global transcript turnover, we searched for sequence elements that correlated with transcript (in)stability and used these sequences to guide tool design. This study probes global RNA turnover in a cyanobacterium, Synechococcus sp. strain PCC 7002, that both has a unique array of RNases that facilitate RNA degradation and is an industrially relevant strain that could be used to convert CO2 and sunlight into useful products.
Collapse
|
34
|
Mukherjee B, Madhu S, Wangikar PP. The role of systems biology in developing non-model cyanobacteria as hosts for chemical production. Curr Opin Biotechnol 2020; 64:62-69. [DOI: 10.1016/j.copbio.2019.10.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Revised: 10/03/2019] [Accepted: 10/03/2019] [Indexed: 11/16/2022]
|
35
|
Sengupta A, Madhu S, Wangikar PP. A Library of Tunable, Portable, and Inducer-Free Promoters Derived from Cyanobacteria. ACS Synth Biol 2020; 9:1790-1801. [PMID: 32551554 DOI: 10.1021/acssynbio.0c00152] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Cyanobacteria are emerging as hosts for various biotechnological applications. The ability to engineer these photosynthetic prokaryotes greatly depends on the availability of well-characterized promoters. Inducer-free promoters of a range of activities may be desirable for the eventual large-scale, outdoor cultivations. Further, several native promoters of cyanobacteria are repressed by high carbon dioxide or light, and it would be of interest to alter this property. We started with PrbcL and PcpcB, the well-characterized native promoters of the model cyanobacterium Synechococcus elongatus PCC 7942, found upstream of the two abundantly expressed genes, Ribulose-1,5-Bisphosphate Carboxylase/Oxygenase, and phycocyanin β-1 subunit, respectively. The library of 48 promoters created via error-prone PCR of these 300-bp-long native promoters showed 2 orders of magnitude dynamic range with activities that were both lower and higher than those of the wild-type promoters. A few mutants of the PrbcL showed greater strength than PcpcB, which is widely considered a superstrong promoter. A number of mutant promoters did not show repression by high CO2 or light, typically found for PrbcL and PcpcB, respectively. Further, the wild-type and mutant promoters showed comparable activities in the fast-growing and stress-tolerant strains S. elongatus PCC 11801 and PCC 11802, suggesting that the library can be used in different cyanobacteria. Interestingly, the majority of the promoters showed strong expression in E. coli, thus adding to the repertoire of inducer-free promoters for this heterotrophic workhorse. Our results have implications in the metabolic engineering of cyanobacteria and E. coli.
Collapse
|
36
|
Engineering salt tolerance of photosynthetic cyanobacteria for seawater utilization. Biotechnol Adv 2020; 43:107578. [PMID: 32553809 DOI: 10.1016/j.biotechadv.2020.107578] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2020] [Revised: 05/17/2020] [Accepted: 06/05/2020] [Indexed: 02/04/2023]
Abstract
Photosynthetic cyanobacteria are capable of utilizing sunlight and CO2 as sole energy and carbon sources, respectively. With genetically modified cyanobacteria being used as a promising chassis to produce various biofuels and chemicals in recent years, future large-scale cultivation of cyanobacteria would have to be performed in seawater, since freshwater supplies of the earth are very limiting. However, high concentration of salt is known to inhibit the growth of cyanobacteria. This review aims at comparing the mechanisms that different cyanobacteria respond to salt stress, and then summarizing various strategies of developing salt-tolerant cyanobacteria for seawater cultivation, including the utilization of halotolerant cyanobacteria and the engineering of salt-tolerant freshwater cyanobacteria. In addition, the challenges and potential strategies related to further improving salt tolerance in cyanobacteria are also discussed.
Collapse
|
37
|
Hill NC, Tay JW, Altus S, Bortz DM, Cameron JC. Life cycle of a cyanobacterial carboxysome. SCIENCE ADVANCES 2020; 6:eaba1269. [PMID: 32494723 PMCID: PMC7202890 DOI: 10.1126/sciadv.aba1269] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Accepted: 02/18/2020] [Indexed: 05/20/2023]
Abstract
Carboxysomes, prototypical bacterial microcompartments (BMCs) found in cyanobacteria, are large (~1 GDa) and essential protein complexes that enhance CO2 fixation. While carboxysome biogenesis has been elucidated, the activity dynamics, lifetime, and degradation of these structures have not been investigated, owing to the inability of tracking individual BMCs over time in vivo. We have developed a fluorescence-imaging platform to simultaneously measure carboxysome number, position, and activity over time in a growing cyanobacterial population, allowing individual carboxysomes to be clustered on the basis of activity and spatial dynamics. We have demonstrated both BMC degradation, characterized by abrupt activity loss followed by polar recruitment of the deactivated complex, and a subclass of ultraproductive carboxysomes. Together, our results reveal the BMC life cycle after biogenesis and describe the first method for measuring activity of single BMCs in vivo.
Collapse
Affiliation(s)
- Nicholas C. Hill
- Department of Biochemistry, University of Colorado, Boulder, CO 80309, USA
- Renewable and Sustainable Energy Institute, University of Colorado, Boulder, CO 80309, USA
| | - Jian Wei Tay
- Renewable and Sustainable Energy Institute, University of Colorado, Boulder, CO 80309, USA
- Biofrontiers Institute, University of Colorado, Boulder, CO 80309, USA
| | - Sabina Altus
- Department of Applied Mathematics, University of Colorado, Boulder, CO 80309, USA
| | - David M. Bortz
- Department of Applied Mathematics, University of Colorado, Boulder, CO 80309, USA
| | - Jeffrey C. Cameron
- Department of Biochemistry, University of Colorado, Boulder, CO 80309, USA
- Renewable and Sustainable Energy Institute, University of Colorado, Boulder, CO 80309, USA
- National Renewable Energy Laboratory, Golden, CO 80401, USA
- Corresponding author.
| |
Collapse
|
38
|
Comer AD, Abraham JP, Steiner AJ, Korosh TC, Markley AL, Pfleger BF. Enhancing photosynthetic production of glycogen-rich biomass for use as a fermentation feedstock. FRONTIERS IN ENERGY RESEARCH 2020; 8:93. [PMID: 34164390 PMCID: PMC8218994 DOI: 10.3389/fenrg.2020.00093] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Current sources of fermentation feedstocks, i.e. corn, sugar cane, or plant biomass, fall short of demand for liquid transportation fuels and commodity chemicals in the United States. Aquatic phototrophs including cyanobacteria have the potential to supplement the supply of current fermentable feedstocks. In this strategy, cells are engineered to accumulate storage molecules including glycogen, cellulose, and/or lipid oils that can be extracted from harvested biomass and fed to heterotrophic organisms engineered to produce desired chemical products. In this manuscript, we examine the production of glycogen in the model cyanobacteria, Synechococcus sp. strain PCC 7002, and subsequent conversion of cyanobacterial biomass by an engineered Escherichia coli to octanoic acid as a model product. In effort to maximize glycogen production, we explored the deletion of catabolic enzymes and overexpression of GlgC, an enzyme that catalyzes the first committed step towards glycogen synthesis. We found that deletion of glgP increased final glycogen titers when cells were grown in diurnal light. Overexpression of GlgC led to a temporal increase in glycogen content but not in an overall increase in final titer or content. The best strains were grown, harvested, and used to formulate media for growth of E. coli. The cyanobacterial media was able to support the growth of an engineered E. coli and produce octanoic acid at the same titer as common laboratory media.
Collapse
Affiliation(s)
- Austin D. Comer
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI 53706, United States
| | - Joshua P. Abraham
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI 53706, United States
| | - Alexander J. Steiner
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI 53706, United States
| | - Travis C. Korosh
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI 53706, United States
| | - Andrew L. Markley
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI 53706, United States
| | - Brian F. Pfleger
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI 53706, United States
- Microbiology Doctoral Training Program, University of Wisconsin-Madison, Madison, WI 53706, United States
- Corresponding author. 3629 Engineering Hall, 1415 Engineering Drive, Madison, WI 53706, United States. Phone: +1 608 890 1940. Fax: +1 608 262-5434.
| |
Collapse
|
39
|
Ng I, Keskin BB, Tan S. A Critical Review of Genome Editing and Synthetic Biology Applications in Metabolic Engineering of Microalgae and Cyanobacteria. Biotechnol J 2020; 15:e1900228. [DOI: 10.1002/biot.201900228] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Revised: 02/07/2020] [Indexed: 12/13/2022]
Affiliation(s)
- I‐Son Ng
- Department of Chemical EngineeringNational Cheng Kung University Tainan 701 Taiwan
| | - Batuhan Birol Keskin
- Department of Chemical EngineeringNational Cheng Kung University Tainan 701 Taiwan
| | - Shih‐I Tan
- Department of Chemical EngineeringNational Cheng Kung University Tainan 701 Taiwan
| |
Collapse
|
40
|
Till P, Toepel J, Bühler B, Mach RL, Mach-Aigner AR. Regulatory systems for gene expression control in cyanobacteria. Appl Microbiol Biotechnol 2020; 104:1977-1991. [PMID: 31965222 PMCID: PMC7007895 DOI: 10.1007/s00253-019-10344-w] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Revised: 12/21/2019] [Accepted: 12/28/2019] [Indexed: 11/24/2022]
Abstract
As photosynthetic microbes, cyanobacteria are attractive hosts for the production of high-value molecules from CO2 and light. Strategies for genetic engineering and tightly controlled gene expression are essential for the biotechnological application of these organisms. Numerous heterologous or native promoter systems were used for constitutive and inducible expression, yet many of them suffer either from leakiness or from a low expression output. Anyway, in recent years, existing systems have been improved and new promoters have been discovered or engineered for cyanobacteria. Moreover, alternative tools and strategies for expression control such as riboswitches, riboregulators or genetic circuits have been developed. In this mini-review, we provide a broad overview on the different tools and approaches for the regulation of gene expression in cyanobacteria and explain their advantages and disadvantages.
Collapse
Affiliation(s)
- Petra Till
- Christian Doppler Laboratory for Optimized Expression of Carbohydrate-Active Enzymes, Institute of Chemical, Environmental and Bioscience Engineering, TU Wien, Gumpendorfer Str. 1a, A-1060, Vienna, Austria
- Institute of Chemical, Environmental and Bioscience Engineering, TU Wien, Gumpendorfer Str. 1a, A-1060, Vienna, Austria
| | - Jörg Toepel
- Department of Solar Materials, Helmholtz-Centre for Environmental Research GmbH-UFZ, Permoserstrasse 15, 04318, Leipzig, Germany
| | - Bruno Bühler
- Department of Solar Materials, Helmholtz-Centre for Environmental Research GmbH-UFZ, Permoserstrasse 15, 04318, Leipzig, Germany
| | - Robert L Mach
- Institute of Chemical, Environmental and Bioscience Engineering, TU Wien, Gumpendorfer Str. 1a, A-1060, Vienna, Austria
| | - Astrid R Mach-Aigner
- Christian Doppler Laboratory for Optimized Expression of Carbohydrate-Active Enzymes, Institute of Chemical, Environmental and Bioscience Engineering, TU Wien, Gumpendorfer Str. 1a, A-1060, Vienna, Austria.
- Institute of Chemical, Environmental and Bioscience Engineering, TU Wien, Gumpendorfer Str. 1a, A-1060, Vienna, Austria.
| |
Collapse
|
41
|
Liu D, Zhang J, Lü C, Xia Y, Liu H, Jiao N, Xun L, Liu J. Synechococcus sp. Strain PCC7002 Uses Sulfide:Quinone Oxidoreductase To Detoxify Exogenous Sulfide and To Convert Endogenous Sulfide to Cellular Sulfane Sulfur. mBio 2020; 11:e03420-19. [PMID: 32098824 PMCID: PMC7042703 DOI: 10.1128/mbio.03420-19] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2020] [Accepted: 01/17/2020] [Indexed: 12/19/2022] Open
Abstract
Eutrophication and deoxygenation possibly occur in coastal waters due to excessive nutrients from agricultural and aquacultural activities, leading to sulfide accumulation. Cyanobacteria, as photosynthetic prokaryotes, play significant roles in carbon fixation in the ocean. Although some cyanobacteria can use sulfide as the electron donor for photosynthesis under anaerobic conditions, little is known on how they interact with sulfide under aerobic conditions. In this study, we report that Synechococcus sp. strain PCC7002 (PCC7002), harboring an sqr gene encoding sulfide:quinone oxidoreductase (SQR), oxidized self-produced sulfide to S0, present as persulfide and polysulfide in the cell. The Δsqr mutant contained less cellular S0 and had increased expression of key genes involved in photosynthesis, but it was less competitive than the wild type in cocultures. Further, PCC7002 with SQR and persulfide dioxygenase (PDO) oxidized exogenous sulfide to tolerate high sulfide levels. Thus, SQR offers some benefits to cyanobacteria even under aerobic conditions, explaining the common presence of SQR in cyanobacteria.IMPORTANCE Cyanobacteria are a major force for primary production via oxygenic photosynthesis in the ocean. A marine cyanobacterium, PCC7002, is actively involved in sulfide metabolism. It uses SQR to detoxify exogenous sulfide, enabling it to survive better than its Δsqr mutant in sulfide-rich environments. PCC7002 also uses SQR to oxidize endogenously generated sulfide to S0, which is required for the proper expression of key genes involved in photosynthesis. Thus, SQR has at least two physiological functions in PCC7002. The observation provides a new perspective for the interplays of C and S cycles.
Collapse
Affiliation(s)
- Daixi Liu
- Institute of Marine Science and Technology, Shandong University, Qingdao, China
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
- Joint Lab for Ocean Research and Education at Dalhousie University, Shandong University and Xiamen University, Qingdao, China
| | - Jiajie Zhang
- Institute of Marine Science and Technology, Shandong University, Qingdao, China
- Joint Lab for Ocean Research and Education at Dalhousie University, Shandong University and Xiamen University, Qingdao, China
| | - Chuanjuan Lü
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Yongzhen Xia
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Huaiwei Liu
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Nianzhi Jiao
- Joint Lab for Ocean Research and Education at Dalhousie University, Shandong University and Xiamen University, Qingdao, China
- Institute of Marine Microbes and Ecospheres, Xiamen University, Xiamen, China
| | - Luying Xun
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
- School of Molecular Biosciences, Washington State University, Pullman, Washington, USA
| | - Jihua Liu
- Institute of Marine Science and Technology, Shandong University, Qingdao, China
- Joint Lab for Ocean Research and Education at Dalhousie University, Shandong University and Xiamen University, Qingdao, China
- Institute of Marine Microbes and Ecospheres, Xiamen University, Xiamen, China
| |
Collapse
|
42
|
Wiltbank LB, Kehoe DM. Diverse light responses of cyanobacteria mediated by phytochrome superfamily photoreceptors. Nat Rev Microbiol 2020; 17:37-50. [PMID: 30410070 DOI: 10.1038/s41579-018-0110-4] [Citation(s) in RCA: 67] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Cyanobacteria are an evolutionarily and ecologically important group of prokaryotes. They exist in diverse habitats, ranging from hot springs and deserts to glaciers and the open ocean. The range of environments that they inhabit can be attributed in part to their ability to sense and respond to changing environmental conditions. As photosynthetic organisms, one of the most crucial parameters for cyanobacteria to monitor is light. Cyanobacteria can sense various wavelengths of light and many possess a range of bilin-binding photoreceptors belonging to the phytochrome superfamily. Vital cellular processes including growth, phototaxis, cell aggregation and photosynthesis are tuned to environmental light conditions by these photoreceptors. In this Review, we examine the physiological responses that are controlled by members of this diverse family of photoreceptors and discuss the signal transduction pathways through which these photoreceptors operate. We highlight specific examples where the activities of multiple photoreceptors function together to fine-tune light responses. We also discuss the potential application of these photosensing systems in optogenetics and synthetic biology.
Collapse
Affiliation(s)
- Lisa B Wiltbank
- Department of Biology, Indiana University, Bloomington, IN, USA
| | - David M Kehoe
- Department of Biology, Indiana University, Bloomington, IN, USA.
| |
Collapse
|
43
|
Hitchcock A, Hunter CN, Canniffe DP. Progress and challenges in engineering cyanobacteria as chassis for light-driven biotechnology. Microb Biotechnol 2019; 13:363-367. [PMID: 31880868 PMCID: PMC7017823 DOI: 10.1111/1751-7915.13526] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 11/29/2019] [Accepted: 12/01/2019] [Indexed: 11/26/2022] Open
Abstract
Cyanobacteria are prokaryotic phototrophs that, in addition to being excellent model organisms for studying photosynthesis, have tremendous potential for light‐driven synthetic biology and biotechnology. These versatile and resilient microorganisms harness the energy of sunlight to oxidise water, generating chemical energy (ATP) and reductant (NADPH) that can be used to drive sustainable synthesis of high‐value natural products in genetically modified strains. In this commentary article for the Synthetic Microbiology Caucus we discuss the great progress that has been made in engineering cyanobacterial hosts as microbial cell factories for solar‐powered biosynthesis. We focus on some of the main areas where the synthetic biology and metabolic engineering tools in cyanobacteria are not as advanced as those in more widely used heterotrophic chassis, and go on to highlight key improvements that we feel are required to unlock the full power of cyanobacteria for future green biotechnology.
Collapse
Affiliation(s)
- Andrew Hitchcock
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, UK
| | - C Neil Hunter
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, UK
| | - Daniel P Canniffe
- Institute of Integrative Biology, University of Liverpool, Liverpool, UK
| |
Collapse
|
44
|
Lin WR, Tan SI, Hsiang CC, Sung PK, Ng IS. Challenges and opportunity of recent genome editing and multi-omics in cyanobacteria and microalgae for biorefinery. BIORESOURCE TECHNOLOGY 2019; 291:121932. [PMID: 31387837 DOI: 10.1016/j.biortech.2019.121932] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Revised: 07/26/2019] [Accepted: 07/27/2019] [Indexed: 06/10/2023]
Abstract
Microalgae and cyanobacteria are easy to culture, with higher growth rates and photosynthetic efficiencies compared to terrestrial plants, and thus generating higher productivity. The concept of microalgal biorefinery is to assimilate carbon dioxide and convert it to chemical energy/value-added products, such as vitamins, carotenoids, fatty acids, proteins and nucleic acids, to be applied in bioenergy, health foods, aquaculture feed, pharmaceutical and medical fields. Therefore, microalgae are annotated as the third generation feedstock in bioenergy and biorefinery. In past decades, many studies thrived to improve the carbon sequestration efficiency as well as enhance value-added compounds from different algae, especially via genetic engineering, synthetic biology, metabolic design and regulation. From the traditional Agrobacterium-mediated transformation DNA to novel CRISPR (clustered regularly interspaced short palindromic repeats) technology applied in microalgae and cyanobacteria, this review has highlighted the genome editing technology for biorefinery that is a highly environmental friendly trend to sustainable and renewable development.
Collapse
Affiliation(s)
- Way-Rong Lin
- Department of Chemical Engineering, National Cheng Kung University, Tainan 701, Taiwan, ROC
| | - Shih-I Tan
- Department of Chemical Engineering, National Cheng Kung University, Tainan 701, Taiwan, ROC
| | - Chuan-Chieh Hsiang
- Department of Chemical Engineering, National Cheng Kung University, Tainan 701, Taiwan, ROC
| | - Po-Kuei Sung
- Department of Chemical Engineering, National Cheng Kung University, Tainan 701, Taiwan, ROC
| | - I-Son Ng
- Department of Chemical Engineering, National Cheng Kung University, Tainan 701, Taiwan, ROC.
| |
Collapse
|
45
|
Vavitsas K, Crozet P, Vinde MH, Davies F, Lemaire SD, Vickers CE. The Synthetic Biology Toolkit for Photosynthetic Microorganisms. PLANT PHYSIOLOGY 2019; 181:14-27. [PMID: 31262955 PMCID: PMC6716251 DOI: 10.1104/pp.19.00345] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Accepted: 06/09/2019] [Indexed: 05/10/2023]
Abstract
Photosynthetic microorganisms offer novel characteristics as synthetic biology chassis, and the toolbox of components and techniques for cyanobacteria and algae is rapidly increasing.
Collapse
Affiliation(s)
- Konstantinos Vavitsas
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St Lucia, Queensland 4072, Australia
- Commonwealth Scientific and Industrial Research Organisation (CSIRO) Synthetic Biology Future Science Platform, CSIRO Land & Water, Brisbane, Queensland 4001, Australia
| | - Pierre Crozet
- Institut de Biologie Physico-Chimique, Unité Mixte de Recherche 8226, Centre National de la Recherche Scientifique, Sorbonne Université, 75005 Paris, France
| | - Marcos Hamborg Vinde
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St Lucia, Queensland 4072, Australia
- Commonwealth Scientific and Industrial Research Organisation (CSIRO) Synthetic Biology Future Science Platform, CSIRO Land & Water, Brisbane, Queensland 4001, Australia
| | - Fiona Davies
- Department of Chemistry, Colorado School of Mines, Golden, Colorado 80401
| | - Stéphane D Lemaire
- Institut de Biologie Physico-Chimique, Unité Mixte de Recherche 8226, Centre National de la Recherche Scientifique, Sorbonne Université, 75005 Paris, France
| | - Claudia E Vickers
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St Lucia, Queensland 4072, Australia
- Commonwealth Scientific and Industrial Research Organisation (CSIRO) Synthetic Biology Future Science Platform, CSIRO Land & Water, Brisbane, Queensland 4001, Australia
| |
Collapse
|
46
|
Bartasun P, Prandi N, Storch M, Aknin Y, Bennett M, Palma A, Baldwin G, Sakuragi Y, Jones PR, Rowland J. The effect of modulating the quantity of enzymes in a model ethanol pathway on metabolic flux in Synechocystis sp. PCC 6803. PeerJ 2019; 7:e7529. [PMID: 31523505 PMCID: PMC6717505 DOI: 10.7717/peerj.7529] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Accepted: 07/22/2019] [Indexed: 12/17/2022] Open
Abstract
Synthetic metabolism allows new metabolic capabilities to be introduced into strains for biotechnology applications. Such engineered metabolic pathways are unlikely to function optimally as initially designed and native metabolism may not efficiently support the introduced pathway without further intervention. To develop our understanding of optimal metabolic engineering strategies, a two-enzyme ethanol pathway consisting of pyruvate decarboxylase and acetaldehyde reductase was introduced into Synechocystis sp. PCC 6803. We characteriseda new set of ribosome binding site sequences in Synechocystis sp. PCC 6803 providing a range of translation strengths for different genes under test. The effect of ribosome-bindingsite sequence, operon design and modifications to native metabolism on pathway flux was analysed by HPLC. The accumulation of all introduced proteins was also quantified using selected reaction monitoring mass spectrometry. Pathway productivity was more strongly dependent on the accumulation of pyruvate decarboxylase than acetaldehyde reductase. In fact, abolishment of reductase over-expression resulted in the greatest ethanol productivity, most likely because strains harbouringsingle-gene constructs accumulated more pyruvate decarboxylase than strains carrying any of the multi-gene constructs. Overall, several lessons were learned. Firstly, the expression level of the first gene in anyoperon influenced the expression level of subsequent genes, demonstrating that translational coupling can also occur in cyanobacteria. Longer operons resulted in lower protein abundance for proximally-encoded cistrons. And, implementation of metabolic engineering strategies that have previously been shown to enhance the growth or yield of pyruvate dependent products, through co-expression with pyruvate kinase and/or fructose-1,6-bisphosphatase/sedoheptulose-1,7-bisphosphatase, indicated that other factors had greater control over growth and metabolic flux under the tested conditions.
Collapse
Affiliation(s)
- Paulina Bartasun
- Department of Life Sciences, Imperial College London, London, United Kingdom
| | - Nicole Prandi
- Department of Life Sciences, Imperial College London, London, United Kingdom
| | - Marko Storch
- Department of Life Sciences, Imperial College London, London, United Kingdom.,Imperial College Centre for Synthetic Biology, Imperial College London, London, United Kingdom
| | - Yarin Aknin
- Department of Life Sciences, Imperial College London, London, United Kingdom.,Institute of Plant Sciences and Genetics in Agriculture, Hebrew University of Jerusalem, Rehovot, Israel
| | - Mark Bennett
- Department of Life Sciences, Imperial College London, London, United Kingdom
| | - Arianna Palma
- Department of Life Sciences, Imperial College London, London, United Kingdom
| | - Geoff Baldwin
- Department of Life Sciences, Imperial College London, London, United Kingdom.,Imperial College Centre for Synthetic Biology, Imperial College London, London, United Kingdom
| | - Yumiko Sakuragi
- Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - Patrik R Jones
- Department of Life Sciences, Imperial College London, London, United Kingdom.,Imperial College Centre for Synthetic Biology, Imperial College London, London, United Kingdom
| | - John Rowland
- Department of Life Sciences, Imperial College London, London, United Kingdom
| |
Collapse
|
47
|
Sengupta A, Sunder AV, Sohoni SV, Wangikar PP. Fine-Tuning Native Promoters of Synechococcus elongatus PCC 7942 To Develop a Synthetic Toolbox for Heterologous Protein Expression. ACS Synth Biol 2019; 8:1219-1223. [PMID: 30973704 DOI: 10.1021/acssynbio.9b00066] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The cyanobacterium Synechococcus elongatus PCC 7942 is a potential photosynthetic cell-factory. In this study, two native promoters from S. elongatus PCC 7942 driving the expression of abundant cyanobacterial proteins phycocyanin (P cpcB7942) and RuBisCO (P rbc7942) were characterized in relation to their sequence features, expression levels, diurnal behavior, and regulation by light and CO2, major abiotic factors important for cyanobacterial growth. P cpcB7942 was repressed under high light intensity, but cultivation at higher CO2 concentration was able to recover promoter activity. On the other hand, P rbc7942 was repressed by elevated CO2 with a negative regulatory region between 300 and 225 bp. Removal of this region flipped the effect of CO2 with Rbc225 being activated only at high CO2 concentration, besides leading to the loss of circadian rhythm. The results from this study on promoter features and regulation will help expand the repertoire of tools for pathway engineering in cyanobacteria.
Collapse
|
48
|
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
| |
Collapse
|
49
|
Pérez AA, Chen Q, Hernández HP, Branco dos Santos F, Hellingwerf KJ. On the use of oxygenic photosynthesis for the sustainable production of commodity chemicals. PHYSIOLOGIA PLANTARUM 2019; 166:413-427. [PMID: 30829400 PMCID: PMC6850307 DOI: 10.1111/ppl.12946] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Revised: 02/15/2019] [Accepted: 02/18/2019] [Indexed: 05/13/2023]
Abstract
A sustainable society will have to largely refrain from the use of fossil carbon deposits. In such a regime, renewable electricity can be harvested as a primary source of energy. However, as for the synthesis of carbon-based materials from bulk chemicals, an alternative is required. A sustainable approach towards this is the synthesis of commodity chemicals from CO2 , water and sunlight. Multiple paths to achieve this have been designed and tested in the domains of chemistry and biology. In the latter, the use of both chemotrophic and phototrophic organisms has been advocated. 'Direct conversion' of CO2 and H2 O, catalyzed by an oxyphototroph, has excellent prospects to become the most economically competitive of these transformations, because of the relative ease of scale-up of this process. Significantly, for a wide range of energy and commodity products, a proof of principle via engineering of the corresponding production organism has been provided. In the optimization of a cyanobacterial production organism, a wide range of aspects has to be addressed. Of these, here we will put our focus on: (1) optimizing the (carbon) flux to the desired product; (2) increasing the genetic stability of the producing organism and (3) maximizing its energy conversion efficiency. Significant advances have been made on all these three aspects during the past 2 years and these will be discussed: (1) increasing the carbon partitioning to >50%; (2) aligning product formation with the growth of the cells and (3) expanding the photosynthetically active radiation region for oxygenic photosynthesis.
Collapse
Affiliation(s)
- Adam A. Pérez
- Molecular Microbial Physiology GroupSwammerdam Institute for Life Sciences, University of Amsterdam1098 XH AmsterdamThe Netherlands
- Photanol BVMatrix VAmsterdam, 1098 XHThe Netherlands
| | - Que Chen
- Molecular Microbial Physiology GroupSwammerdam Institute for Life Sciences, University of Amsterdam1098 XH AmsterdamThe Netherlands
| | - Hugo Pineda Hernández
- Molecular Microbial Physiology GroupSwammerdam Institute for Life Sciences, University of Amsterdam1098 XH AmsterdamThe Netherlands
| | - Filipe Branco dos Santos
- Molecular Microbial Physiology GroupSwammerdam Institute for Life Sciences, University of Amsterdam1098 XH AmsterdamThe Netherlands
| | - Klaas J. Hellingwerf
- Molecular Microbial Physiology GroupSwammerdam Institute for Life Sciences, University of Amsterdam1098 XH AmsterdamThe Netherlands
- Photanol BVMatrix VAmsterdam, 1098 XHThe Netherlands
| |
Collapse
|
50
|
Vasudevan R, Gale GAR, Schiavon AA, Puzorjov A, Malin J, Gillespie MD, Vavitsas K, Zulkower V, Wang B, Howe CJ, Lea-Smith DJ, McCormick AJ. CyanoGate: A Modular Cloning Suite for Engineering Cyanobacteria Based on the Plant MoClo Syntax. PLANT PHYSIOLOGY 2019; 180:39-55. [PMID: 30819783 PMCID: PMC6501082 DOI: 10.1104/pp.18.01401] [Citation(s) in RCA: 87] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Accepted: 02/16/2019] [Indexed: 05/10/2023]
Abstract
Recent advances in synthetic biology research have been underpinned by an exponential increase in available genomic information and a proliferation of advanced DNA assembly tools. The adoption of plasmid vector assembly standards and parts libraries has greatly enhanced the reproducibility of research and the exchange of parts between different labs and biological systems. However, a standardized modular cloning (MoClo) system is not yet available for cyanobacteria, which lag behind other prokaryotes in synthetic biology despite their huge potential regarding biotechnological applications. By building on the assembly library and syntax of the Plant Golden Gate MoClo kit, we have developed a versatile system called CyanoGate that unites cyanobacteria with plant and algal systems. Here, we describe the generation of a suite of parts and acceptor vectors for making (1) marked/unmarked knock-outs or integrations using an integrative acceptor vector, and (2) transient multigene expression and repression systems using known and previously undescribed replicative vectors. We tested and compared the CyanoGate system in the established model cyanobacterium Synechocystis sp. PCC 6803 and the more recently described fast-growing strain Synechococcus elongatus UTEX 2973. The UTEX 2973 fast-growth phenotype was only evident under specific growth conditions; however, UTEX 2973 accumulated high levels of proteins with strong native or synthetic promoters. The system is publicly available and can be readily expanded to accommodate other standardized MoClo parts to accelerate the development of reliable synthetic biology tools for the cyanobacterial community.
Collapse
Affiliation(s)
- Ravendran Vasudevan
- Institute of Molecular Plant Sciences, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3BF, United Kingdom
- Centre for Synthetic and Systems Biology, University of Edinburgh, Edinburgh EH9 3BF, United Kingdom
| | - Grant A R Gale
- Institute of Molecular Plant Sciences, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3BF, United Kingdom
- Centre for Synthetic and Systems Biology, University of Edinburgh, Edinburgh EH9 3BF, United Kingdom
- Institute of Quantitative Biology, Biochemistry and Biotechnology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3FF, United Kingdom
| | - Alejandra A Schiavon
- Institute of Molecular Plant Sciences, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3BF, United Kingdom
- Centre for Synthetic and Systems Biology, University of Edinburgh, Edinburgh EH9 3BF, United Kingdom
| | - Anton Puzorjov
- Institute of Molecular Plant Sciences, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3BF, United Kingdom
- Centre for Synthetic and Systems Biology, University of Edinburgh, Edinburgh EH9 3BF, United Kingdom
| | - John Malin
- Institute of Molecular Plant Sciences, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3BF, United Kingdom
- Centre for Synthetic and Systems Biology, University of Edinburgh, Edinburgh EH9 3BF, United Kingdom
| | - Michael D Gillespie
- School of Biological Sciences, University of East Anglia, Norwich NR4 7TJ, United Kingdom
| | - Konstantinos Vavitsas
- Australian Institute of Bioengineering and Nanotechnology, The University of Queensland, Brisbane, Queensland 4072, Australia
- CSIRO, Synthetic Biology Future Science Platform, Brisbane, Queensland 4001, Australia
| | - Valentin Zulkower
- Centre for Synthetic and Systems Biology, University of Edinburgh, Edinburgh EH9 3BF, United Kingdom
| | - Baojun Wang
- Centre for Synthetic and Systems Biology, University of Edinburgh, Edinburgh EH9 3BF, United Kingdom
- Institute of Quantitative Biology, Biochemistry and Biotechnology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3FF, United Kingdom
| | - Christopher J Howe
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1QW, United Kingdom
| | - David J Lea-Smith
- School of Biological Sciences, University of East Anglia, Norwich NR4 7TJ, United Kingdom
| | - Alistair J McCormick
- Institute of Molecular Plant Sciences, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3BF, United Kingdom
- Centre for Synthetic and Systems Biology, University of Edinburgh, Edinburgh EH9 3BF, United Kingdom
| |
Collapse
|