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Zhang J, Sun T, Zhang W, Chen L. Identification of acidic stress-responsive genes and acid tolerance engineering in Synechococcus elongatus PCC 7942. Appl Microbiol Biotechnol 2024; 108:115. [PMID: 38204133 PMCID: PMC10781874 DOI: 10.1007/s00253-023-12984-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Revised: 12/11/2023] [Accepted: 12/21/2023] [Indexed: 01/12/2024]
Abstract
Cyanobacteria are excellent autotrophic photosynthetic chassis employed in synthetic biology, and previous studies have suggested that they have alkaline tolerance but low acid tolerance, significantly limiting their productivity as photosynthetic chassis and necessitating investigations into the acid stress resistance mechanism. In this study, differentially expressed genes were obtained by RNA sequencing-based comparative transcriptomic analysis under long-term acidic stress conditions and acidic shock treatment, in the model cyanobacterium Synechococcus elongatus PCC 7942. A pathway enrichment analysis revealed the upregulated and downregulated pathways during long-term acidic and shock stress treatment. The subsequent single gene knockout and phenotype analysis showed that under acidic stress conditions, the strains with chlL, chlN, pex, synpcc7942_2038, synpcc7942_1890, or synpcc7942_2547 knocked out grew worse than the wild type, suggesting their involvement in acid tolerance. This finding was further confirmed by introducing the corresponding genes back into the knockout mutant individually. Moreover, individual overexpression of the chlL and chlN genes in the wild type successfully improved the tolerance of S. elongatus PCC 7942 to acidic stress. This work successfully identified six genes involved in acidic stress responses, and overexpressing chIL or chIN individually successfully improved acid tolerance in S. elongatus PCC 7942, providing valuable information to better understand the acid resistance mechanism in S. elongatus PCC 7942 and novel insights into the robustness and tolerance engineering of cyanobacterial chassis. KEY POINTS: • DEGs were identified by RNA-seq based transcriptomics analysis in response to acidic stress in S. elongatus PCC 7942. • Six genes were identified to be involved in acid tolerance in S. elongatus PCC 7942. • Overexpression of chIL or chIN individually successfully improved the acid tolerance of S. elongatus PCC 7942.
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Affiliation(s)
- Jie Zhang
- Laboratory of Synthetic Microbiology, School of Chemical Engineering & Technology, Tianjin University, Tianjin, 300072, People's Republic of China
- Frontiers Science Center for Synthetic Biology, Tianjin University, Tianjin, 300072, People's Republic of China
- Key Laboratory of Systems Bioengineering (MOE), Tianjin University, Tianjin, 300072, People's Republic of China
| | - Tao Sun
- Laboratory of Synthetic Microbiology, School of Chemical Engineering & Technology, Tianjin University, Tianjin, 300072, People's Republic of China
- Frontiers Science Center for Synthetic Biology, Tianjin University, Tianjin, 300072, People's Republic of China
- Key Laboratory of Systems Bioengineering (MOE), Tianjin University, Tianjin, 300072, People's Republic of China
- Center for Biosafety Research and Strategy, Tianjin University, Tianjin, 300072, People's Republic of China
| | - Weiwen Zhang
- Laboratory of Synthetic Microbiology, School of Chemical Engineering & Technology, Tianjin University, Tianjin, 300072, People's Republic of China
- Frontiers Science Center for Synthetic Biology, Tianjin University, Tianjin, 300072, People's Republic of China
- Key Laboratory of Systems Bioengineering (MOE), Tianjin University, Tianjin, 300072, People's Republic of China
- Center for Biosafety Research and Strategy, Tianjin University, Tianjin, 300072, People's Republic of China
| | - Lei Chen
- Laboratory of Synthetic Microbiology, School of Chemical Engineering & Technology, Tianjin University, Tianjin, 300072, People's Republic of China.
- Frontiers Science Center for Synthetic Biology, Tianjin University, Tianjin, 300072, People's Republic of China.
- Key Laboratory of Systems Bioengineering (MOE), Tianjin University, Tianjin, 300072, People's Republic of China.
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2
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Zhong J, Wang Y, Chen Z, Yalikun Y, He L, Liu T, Ma G. Engineering cyanobacteria as a new platform for producing taxol precursors directly from carbon dioxide. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2024; 17:99. [PMID: 39014505 PMCID: PMC11253407 DOI: 10.1186/s13068-024-02555-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2024] [Accepted: 07/10/2024] [Indexed: 07/18/2024]
Abstract
Taxol serves as an efficient natural anticancer agent with extensive applications in the treatment of diverse malignancies. Although advances in synthetic biology have enabled the de novo synthesis of taxol precursors in various microbial chassis, the total biosynthesis of taxol remains challengable owing to the restricted oxidation efficiency in heterotrophic microbes. Here, we engineered Synechocystis sp. PCC 6803 with modular metabolic pathways consisting of the methylerythritol phosphate pathway enzymes and taxol biosynthetic enzymes for production of taxadiene-5α-ol (T5α-ol), the key oxygenated intermediate of taxol. The best strain DIGT-P560 produced up to 17.43 mg/L of oxygenated taxanes and 4.32 mg/L of T5α-ol. Moreover, transcriptomic analysis of DIGT-P560 revealed that establishing a oxygenated taxane flux may enhance photosynthetic electron transfer efficiency and central metabolism in the engineered strain to ameliorate the metabolic disturbances triggered by the incorporation of exogenous genes. This is the first demonstration of photosynthetic production of taxadiene-5α-ol from CO2 in cyanobacteria, highlighting the broad prospects of engineered cyanobacteria as bio-solar cell factories for valuable terpenoids production and expanding the ideas for further rational engineering and optimization.
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Affiliation(s)
- Jialing Zhong
- Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders (Ministry of Education), Shanghai Jiao Tong University, No. 800 Dongchuan Rd., Shanghai, 200240, People's Republic of China
| | - Yushu Wang
- Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders (Ministry of Education), Shanghai Jiao Tong University, No. 800 Dongchuan Rd., Shanghai, 200240, People's Republic of China
| | - Zhuoyang Chen
- Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders (Ministry of Education), Shanghai Jiao Tong University, No. 800 Dongchuan Rd., Shanghai, 200240, People's Republic of China
| | - Yaliqin Yalikun
- Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders (Ministry of Education), Shanghai Jiao Tong University, No. 800 Dongchuan Rd., Shanghai, 200240, People's Republic of China
| | - Lin He
- Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders (Ministry of Education), Shanghai Jiao Tong University, No. 800 Dongchuan Rd., Shanghai, 200240, People's Republic of China
| | - Tiangang Liu
- School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, People's Republic of China
| | - Gang Ma
- Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders (Ministry of Education), Shanghai Jiao Tong University, No. 800 Dongchuan Rd., Shanghai, 200240, People's Republic of China.
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3
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Tiwari D, Kumar N, Bongirwar R, Shukla P. Nutraceutical prospects of genetically engineered cyanobacteria- technological updates and significance. World J Microbiol Biotechnol 2024; 40:263. [PMID: 38980547 DOI: 10.1007/s11274-024-04064-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2024] [Accepted: 06/23/2024] [Indexed: 07/10/2024]
Abstract
Genetically engineered cyanobacterial strains that have improved growth rate, biomass productivity, and metabolite productivity could be a better option for sustainable bio-metabolite production. The global demand for biobased metabolites with nutraceuticals and health benefits has increased due to their safety and plausible therapeutic and nutritional utility. Cyanobacteria are solar-powered green cellular factories that can be genetically tuned to produce metabolites with nutraceutical and pharmaceutical benefits. The present review discusses biotechnological endeavors for producing bioprospective compounds from genetically engineered cyanobacteria and discusses the challenges and troubleshooting faced during metabolite production. This review explores the cyanobacterial versatility, the use of engineered strains, and the techno-economic challenges associated with scaling up metabolite production from cyanobacteria. Challenges to produce cyanobacterial bioactive compounds with remarkable nutraceutical values have been discussed. Additionally, this review also summarises the challenges and future prospects of metabolite production from genetically engineered cyanobacteria as a sustainable approach.
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Affiliation(s)
- Deepali Tiwari
- Enzyme Technology and Protein Bioinformatics Laboratory, School of Biotechnology, Institute of Science, Banaras Hindu University, Varanasi, 221005, Uttar Pradesh, India
| | - Niwas Kumar
- Enzyme Technology and Protein Bioinformatics Laboratory, School of Biotechnology, Institute of Science, Banaras Hindu University, Varanasi, 221005, Uttar Pradesh, India
| | - Riya Bongirwar
- Enzyme Technology and Protein Bioinformatics Laboratory, School of Biotechnology, Institute of Science, Banaras Hindu University, Varanasi, 221005, Uttar Pradesh, India
| | - Pratyoosh Shukla
- Enzyme Technology and Protein Bioinformatics Laboratory, School of Biotechnology, Institute of Science, Banaras Hindu University, Varanasi, 221005, Uttar Pradesh, India.
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4
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Nawaz T, Gu L, Gibbons J, Hu Z, Zhou R. Bridging Nature and Engineering: Protein-Derived Materials for Bio-Inspired Applications. Biomimetics (Basel) 2024; 9:373. [PMID: 38921253 PMCID: PMC11201842 DOI: 10.3390/biomimetics9060373] [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: 04/28/2024] [Revised: 06/11/2024] [Accepted: 06/13/2024] [Indexed: 06/27/2024] Open
Abstract
The sophisticated, elegant protein-polymers designed by nature can serve as inspiration to redesign and biomanufacture protein-based materials using synthetic biology. Historically, petro-based polymeric materials have dominated industrial activities, consequently transforming our way of living. While this benefits humans, the fabrication and disposal of these materials causes environmental sustainability challenges. Fortunately, protein-based biopolymers can compete with and potentially surpass the performance of petro-based polymers because they can be biologically produced and degraded in an environmentally friendly fashion. This paper reviews four groups of protein-based polymers, including fibrous proteins (collagen, silk fibroin, fibrillin, and keratin), elastomeric proteins (elastin, resilin, and wheat glutenin), adhesive/matrix proteins (spongin and conchiolin), and cyanophycin. We discuss the connection between protein sequence, structure, function, and biomimetic applications. Protein engineering techniques, such as directed evolution and rational design, can be used to improve the functionality of natural protein-based materials. For example, the inclusion of specific protein domains, particularly those observed in structural proteins, such as silk and collagen, enables the creation of novel biomimetic materials with exceptional mechanical properties and adaptability. This review also discusses recent advancements in the production and application of new protein-based materials through the approach of synthetic biology combined biomimetics, providing insight for future research and development of cutting-edge bio-inspired products. Protein-based polymers that utilize nature's designs as a base, then modified by advancements at the intersection of biology and engineering, may provide mankind with more sustainable products.
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Affiliation(s)
- Taufiq Nawaz
- Department of Biology and Microbiology, South Dakota State University, Brookings, SD 57007, USA;
| | - Liping Gu
- Department of Biology and Microbiology, South Dakota State University, Brookings, SD 57007, USA;
| | | | - Zhong Hu
- Department of Mechanical Engineering, South Dakota State University, Brookings, SD 57007, USA;
| | - Ruanbao Zhou
- Department of Biology and Microbiology, South Dakota State University, Brookings, SD 57007, USA;
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5
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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.
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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
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6
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Madhu S, Sengupta A, Sarnaik AP, Wangikar PP. Expanding the synthetic biology repertoire of a fast-growing cyanobacterium Synechococcus elongatus PCC 11801. Biotechnol Bioeng 2024. [PMID: 38773863 DOI: 10.1002/bit.28740] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2023] [Revised: 05/04/2024] [Accepted: 05/07/2024] [Indexed: 05/24/2024]
Abstract
Synechococcus elongatus PCC 11801 is a fast-growing cyanobacterium, exhibiting high tolerance to environmental stresses. We have earlier characterized its genome and analysed its transcriptome and proteome. However, to deploy it as a potential cell factory, it is necessary to expand its synthetic biology toolbox, including promoter elements and ribosome binding sites (RBSs). Here, based on the global transcriptome analysis, 48 native promoters of the genes with high transcript count were characterized using a fluorescent reporter system. The promoters PcpcB, PpsbA1, and P11770 exhibited consistently high fluorescence under all the cultivation conditions. Similarly, from the genome data and proteome analysis, 534 operons were identified. Fifteen intergenic regions exhibiting higher protein expression from the downstream gene were systematically characterized for identifying RBSs, using an operon construct comprising fluorescent protein genes eyfp and mTurq under PcpcB (PcpcB:eyfp:RBS:mTurq:TrrnB). Overall, the work presents promoter and RBS sequence libraries, with varying strengths, to expedite bioengineering of PCC 11801.
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Affiliation(s)
- Swati Madhu
- Department of Chemical Engineering, Indian Institute of Technology Bombay, Mumbai, India
| | - Annesha Sengupta
- Department of Chemical Engineering, Indian Institute of Technology Bombay, Mumbai, India
| | - Aditya P Sarnaik
- Department of Chemical Engineering, Indian Institute of Technology Bombay, Mumbai, India
| | - Pramod P Wangikar
- Department of Chemical Engineering, Indian Institute of Technology Bombay, Mumbai, India
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7
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Majhi BK, Melis A. Recombinant protein synthesis and isolation of human interferon alpha-2 in cyanobacteria. BIORESOURCE TECHNOLOGY 2024; 400:130664. [PMID: 38583672 DOI: 10.1016/j.biortech.2024.130664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Revised: 04/01/2024] [Accepted: 04/04/2024] [Indexed: 04/09/2024]
Abstract
Synechocystis sp. PCC 6803 (Synechocystis) is a unicellular photosynthetic microorganism that has been used as a model for photo-biochemical research. It comprises a potential cell factory for the generation of valuable bioactive compounds, therapeutic proteins, and possibly biofuels. Fusion constructs of recombinant proteins with the CpcA α-subunit or CpcB β-subunit of phycocyanin in Synechocystis have enabled true over-expression of several isoprenoid pathway enzymes and biopharmaceutical proteins to levels of 10-20 % of the total cellular protein. The present work employed the human interferon α-2 protein, as a study case of over-expression and downstream processing. It advanced the state of the art in the fusion constructs for protein overexpression technology by developing the bioresource for target protein separation from the fusion construct and isolation in substantially enriched or pure form. The work brings the cyanobacterial cell factory concept closer to meaningful commercial application for the photosynthetic production of useful recombinant proteins.
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Affiliation(s)
- Bharat K Majhi
- Department of Plant and Microbial Biology, 111 Koshland Hall, MC-3102, University of California, Berkeley, CA 94720-3102, USA
| | - Anastasios Melis
- Department of Plant and Microbial Biology, 111 Koshland Hall, MC-3102, University of California, Berkeley, CA 94720-3102, USA.
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8
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Hu Q, Wang J, Liu C, Feng Y, Chen H. Determinants of mer Promoter Activity from Pseudomonas aeruginosa. Genes (Basel) 2024; 15:490. [PMID: 38674424 PMCID: PMC11049809 DOI: 10.3390/genes15040490] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2024] [Revised: 04/11/2024] [Accepted: 04/12/2024] [Indexed: 04/28/2024] Open
Abstract
Since the MerR family is known for its special regulatory mechanism, we aimed to explore which factors determine the expression activity of the mer promoter. The Tn501/Tn21 mer promoter contains an abnormally long spacer (19 bp) between the -35 and -10 elements, which is essential for the unique DNA distortion mechanism. To further understand the role of base sequences in the mer promoter spacer, this study systematically engineered a series of mutant derivatives and used luminescent and fluorescent reporter genes to investigate the expression activity of these derivatives. The results reveal that the expression activity of the mer promoter is synergistically modulated by the spacer length (17 bp is optimal) and the region upstream of -10 (especially -13G). The spacing is regulated by MerR transcription factors through symmetrical sequences, and -13G presumably functions through interaction with the RNA polymerase sigma-70 subunit.
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Affiliation(s)
| | | | | | | | - Hao Chen
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China; (Q.H.); (J.W.); (C.L.); (Y.F.)
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9
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Cheng L, Zhang Z, Zhu D, Luo Q, Lu X. Glucosylglycerol phosphorylase, a potential novel pathway of microbial glucosylglycerol catabolism. Appl Microbiol Biotechnol 2024; 108:214. [PMID: 38363425 PMCID: PMC10873239 DOI: 10.1007/s00253-024-13035-3] [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: 11/08/2023] [Revised: 01/11/2024] [Accepted: 01/26/2024] [Indexed: 02/17/2024]
Abstract
Glucosylglycerol (GG) is a natural compatible solute that can be synthesized by many cyanobacteria and a few heterotrophic bacteria under high salinity conditions. In cyanobacteria, GG is synthesized by GG-phosphate synthase and GG-phosphate phosphatase, and a hydrolase GGHA catalyzes its degradation. In heterotrophic bacteria (such as some Marinobacter species), a fused form of GG-phosphate phosphatase and GG-phosphate synthase is present, but the cyanobacteria-like degradation pathway is not available. Instead, a phosphorylase GGP, of which the coding gene is located adjacent to the gene that encodes the GG-synthesizing enzyme, is supposed to perform the GG degradation function. In the present study, a GGP homolog from the salt-tolerant M. salinexigens ZYF650T was characterized. The recombinant GGP catalyzed GG decomposition via a two-step process of phosphorolysis and hydrolysis in vitro and exhibited high substrate specificity toward GG. The activity of GGP was enhanced by inorganic salts at low concentrations but significantly inhibited by increasing salt concentrations. While the investigation on the physiological role of GGP in M. salinexigens ZYF650T was limited due to the failed induction of GG production, the heterologous expression of ggp in the living cells of the GG-producing cyanobacterium Synechocystis sp. PCC 6803 significantly reduced the salt-induced GG accumulation. Together, these data suggested that GGP may represent a novel pathway of microbial GG catabolism. KEY POINTS: • GGP catalyzes GG degradation by a process of phosphorolysis and hydrolysis • GGP-catalyzed GG degradation is different from GGHA-based GG degradation • GGP represents a potential novel pathway of microbial GG catabolism.
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Affiliation(s)
- Lin Cheng
- College of Chemical Engineering and Materials Sciences, Tianjin University of Science & Technology, Tianjin, 300457, China
- Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Songling Rd 189, Qingdao, 266101, China
| | - Zhichao Zhang
- Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Songling Rd 189, Qingdao, 266101, China
- Shandong Energy Institute, Songling Rd 189, Qingdao, 266101, China
- Qingdao New Energy Shandong Laboratory, Songling Rd 189, Qingdao, 266101, China
| | - Daling Zhu
- College of Chemical Engineering and Materials Sciences, Tianjin University of Science & Technology, Tianjin, 300457, China.
| | - Quan Luo
- Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Songling Rd 189, Qingdao, 266101, China.
- Shandong Energy Institute, Songling Rd 189, Qingdao, 266101, China.
- Qingdao New Energy Shandong Laboratory, Songling Rd 189, Qingdao, 266101, China.
| | - Xuefeng Lu
- Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Songling Rd 189, Qingdao, 266101, China
- Shandong Energy Institute, Songling Rd 189, Qingdao, 266101, China
- Qingdao New Energy Shandong Laboratory, Songling Rd 189, Qingdao, 266101, China
- Marine Biology and Biotechnology Laboratory, Qingdao National Laboratory for Marine Science and Technology, Wenhai Rd 168, Qingdao, 266237, China
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10
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Cao K, Cui Y, Sun F, Zhang H, Fan J, Ge B, Cao Y, Wang X, Zhu X, Wei Z, Yao Q, Ma J, Wang Y, Meng C, Gao Z. Metabolic engineering and synthetic biology strategies for producing high-value natural pigments in Microalgae. Biotechnol Adv 2023; 68:108236. [PMID: 37586543 DOI: 10.1016/j.biotechadv.2023.108236] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2023] [Revised: 07/16/2023] [Accepted: 08/11/2023] [Indexed: 08/18/2023]
Abstract
Microalgae are microorganisms capable of producing bioactive compounds using photosynthesis. Microalgae contain a variety of high value-added natural pigments such as carotenoids, phycobilins, and chlorophylls. These pigments play an important role in many areas such as food, pharmaceuticals, and cosmetics. Natural pigments have a health value that is unmatched by synthetic pigments. However, the current commercial production of natural pigments from microalgae is not able to meet the growing market demand. The use of metabolic engineering and synthetic biological strategies to improve the production performance of microalgal cell factories is essential to promote the large-scale production of high-value pigments from microalgae. This paper reviews the health and economic values, the applications, and the synthesis pathways of microalgal pigments. Overall, this review aims to highlight the latest research progress in metabolic engineering and synthetic biology in constructing engineered strains of microalgae with high-value pigments and the application of CRISPR technology and multi-omics in this context. Finally, we conclude with a discussion on the bottlenecks and challenges of microalgal pigment production and their future development prospects.
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Affiliation(s)
- Kai Cao
- School of Pharmacy, Binzhou Medical University, Yantai 264003, China; School of Life Sciences and medicine, Shandong University of Technology, Zibo 255049, China
| | - Yulin Cui
- School of Pharmacy, Binzhou Medical University, Yantai 264003, China
| | - Fengjie Sun
- Department of Biological Sciences, School of Science and Technology, Georgia Gwinnett College, Lawrenceville, GA 30043, USA
| | - Hao Zhang
- School of Pharmacy, Binzhou Medical University, Yantai 264003, China
| | - Jianhua Fan
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Baosheng Ge
- State Key Laboratory of Heavy Oil Processing and Center for Bioengineering and Biotechnology, China University of Petroleum (East China), Qingdao 266580, China
| | - Yujiao Cao
- School of Foreign Languages, Shandong University of Technology, Zibo 255090, China
| | - Xiaodong Wang
- School of Pharmacy, Binzhou Medical University, Yantai 264003, China
| | - Xiangyu Zhu
- School of Pharmacy, Binzhou Medical University, Yantai 264003, China; School of Life Sciences and medicine, Shandong University of Technology, Zibo 255049, China
| | - Zuoxi Wei
- School of Life Sciences and medicine, Shandong University of Technology, Zibo 255049, China
| | - Qingshou Yao
- School of Pharmacy, Binzhou Medical University, Yantai 264003, China
| | - Jinju Ma
- School of Pharmacy, Binzhou Medical University, Yantai 264003, China
| | - Yu Wang
- School of Pharmacy, Binzhou Medical University, Yantai 264003, China
| | - Chunxiao Meng
- School of Pharmacy, Binzhou Medical University, Yantai 264003, China.
| | - Zhengquan Gao
- School of Pharmacy, Binzhou Medical University, Yantai 264003, China.
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11
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Cao K, Wang X, Sun F, Zhang H, Cui Y, Cao Y, Yao Q, Zhu X, Yao T, Wang M, Meng C, Gao Z. Promoting Heme and Phycocyanin Biosynthesis in Synechocystis sp. PCC 6803 by Overexpression of Porphyrin Pathway Genes with Genetic Engineering. Mar Drugs 2023; 21:403. [PMID: 37504934 PMCID: PMC10382063 DOI: 10.3390/md21070403] [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: 06/08/2023] [Revised: 07/08/2023] [Accepted: 07/12/2023] [Indexed: 07/29/2023] Open
Abstract
Due to their unique biochemical and spectroscopic properties, both heme and phycocyanobilin are widely applied in the medical and food industries. Synechocystis sp. PCC 6803 contains both heme and phycocyanin, and is capable of synthesizing phycocyanin using heme as a precursor. The aim of this study was to uncover viable metabolic targets in the porphyrin pathway from Synechocystis sp. PCC 6803 to promote the accumulation of heme and phycocyanin in the recombinant strains of microalgae. A total of 10 genes related to heme synthesis pathway derived from Synechococcus elongatus PCC 7942 and 12 genes related to endogenous heme synthesis were individually overexpressed in strain PCC 6803. The growth rate and pigment content (heme, phycocyanin, chlorophyll a and carotenoids) of 22 recombinant algal strains were characterized. Quantitative real-time PCR technology was used to investigate the molecular mechanisms underlying the changes in physiological indicators in the recombinant algal strains. Among the 22 mutant strains, the mutant overexpressing the haemoglobin gene (glbN) of strain PCC 6803 had the highest heme content, which was 2.5 times higher than the wild type; the mutant overexpressing the gene of strain PCC 7942 (hemF) had the highest phycocyanin content, which was 4.57 times higher than the wild type. Overall, the results suggest that genes in the porphyrin pathway could significantly affect the heme and phycocyanin content in strain PCC 6803. Our study provides novel crucial targets for promoting the accumulation of heme and phycocyanin in cyanobacteria.
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Affiliation(s)
- Kai Cao
- School of Life Sciences and Medicine, Shandong University of Technology, Zibo 255049, China
- School of Pharmacy, Binzhou Medical University, Yantai 264003, China
| | - Xiaodong Wang
- School of Life Sciences and Medicine, Shandong University of Technology, Zibo 255049, China
| | - Fengjie Sun
- Department of Biological Sciences, School of Science and Technology, Georgia Gwinnett College, Lawrenceville, GA 30043, USA
| | - Hao Zhang
- School of Pharmacy, Binzhou Medical University, Yantai 264003, China
| | - Yulin Cui
- School of Pharmacy, Binzhou Medical University, Yantai 264003, China
| | - Yujiao Cao
- School of Foreign Languages, Shandong University of Technology, Zibo 255090, China
| | - Qingshou Yao
- School of Pharmacy, Binzhou Medical University, Yantai 264003, China
| | - Xiangyu Zhu
- School of Pharmacy, Binzhou Medical University, Yantai 264003, China
| | - Ting Yao
- School of Pharmacy, Binzhou Medical University, Yantai 264003, China
| | - Meng Wang
- Yantai Hongyuan Bio-Fertilizer Co., Ltd., Yantai 264000, China
| | - Chunxiao Meng
- School of Life Sciences and Medicine, Shandong University of Technology, Zibo 255049, China
- School of Pharmacy, Binzhou Medical University, Yantai 264003, China
| | - Zhengquan Gao
- School of Life Sciences and Medicine, Shandong University of Technology, Zibo 255049, China
- School of Pharmacy, Binzhou Medical University, Yantai 264003, China
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12
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Ortega-Martínez P, Roldán M, Díaz-Troya S, Florencio FJ. Stress response requires an efficient connection between glycogen and central carbon metabolism by phosphoglucomutases in cyanobacteria. JOURNAL OF EXPERIMENTAL BOTANY 2023; 74:1532-1550. [PMID: 36454663 PMCID: PMC10010611 DOI: 10.1093/jxb/erac474] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Accepted: 11/28/2022] [Indexed: 06/17/2023]
Abstract
Glycogen and starch are the main storage polysaccharides, acting as a source of carbon and energy when necessary. Interconversion of glucose-1-phosphate and glucose-6-phosphate by phosphoglucomutases connects the metabolism of these polysaccharides with central carbon metabolism. However, knowledge about how this connection affects the ability of cells to cope with environmental stresses is still scarce. The cyanobacterium Synechocystis sp. PCC 6803 has two enzymes with phosphoglucomutase activity, PGM (phosphoglucomutase) and PMM/PGM (phosphomannomutase/phosphoglucomutase). In this work, we generated a null mutant of PGM (∆PGM) that exhibits very reduced phosphoglucomutase activity (1% of wild type activity). Although this mutant accumulates moderate amounts of glycogen, its phenotype resembles that of glycogen-less mutants, including high light sensitivity and altered response to nitrogen deprivation. Using an on/off arsenite promoter, we demonstrate that PMM/PGM is essential for growth and responsible for the remaining phosphoglucomutase activity in the ∆PGM strain. Furthermore, overexpression of PMM/PGM in the ∆PGM strain is enough to revoke the phenotype of this mutant. These results emphasize the importance of an adequate flux between glycogen and central carbon metabolism to maintain cellular fitness and indicate that although PGM is the main phosphoglucomutase activity, the phosphoglucomutase activity of PMM/PGM can substitute it when expressed in sufficient amounts.
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Affiliation(s)
- Pablo Ortega-Martínez
- Instituto de Bioquímica Vegetal y Fotosíntesis, Universidad de Sevilla, Consejo Superior de Investigaciones Científicas, Américo Vespucio 49, Sevilla, 41092, Spain
- Departamento de Bioquímica Vegetal y Biología Molecular, Facultad de Biología, Universidad de Sevilla, Profesor García González s/n, Sevilla, 41012, Spain
| | - Miguel Roldán
- Departamento de Bioquímica Vegetal y Biología Molecular, Facultad de Biología, Universidad de Sevilla, Profesor García González s/n, Sevilla, 41012, Spain
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Satta A, Esquirol L, Ebert BE. Current Metabolic Engineering Strategies for Photosynthetic Bioproduction in Cyanobacteria. Microorganisms 2023; 11:microorganisms11020455. [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.
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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
- Correspondence:
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14
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Malihan‐Yap L, Grimm HC, Kourist R. Recent Advances in Cyanobacterial Biotransformations. CHEM-ING-TECH 2022. [DOI: 10.1002/cite.202200077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Lenny Malihan‐Yap
- Graz University of Technology Institute of Molecular Biotechnology NAWI Graz 8010 Graz Austria
| | - Hanna C. Grimm
- Graz University of Technology Institute of Molecular Biotechnology NAWI Graz 8010 Graz Austria
| | - Robert Kourist
- Graz University of Technology Institute of Molecular Biotechnology NAWI Graz 8010 Graz Austria
- ACIB GmbH 8010 Graz Austria
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15
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Rautela A, Kumar S. Engineering plant family TPS into cyanobacterial host for terpenoids production. PLANT CELL REPORTS 2022; 41:1791-1803. [PMID: 35789422 PMCID: PMC9253243 DOI: 10.1007/s00299-022-02892-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Accepted: 06/05/2022] [Indexed: 05/03/2023]
Abstract
Terpenoids are synthesized naturally by plants as secondary metabolites, and are diverse and complex in structure with multiple applications in bioenergy, food, cosmetics, and medicine. This makes the production of terpenoids such as isoprene, β-phellandrene, farnesene, amorphadiene, and squalene valuable, owing to which their industrial demand cannot be fulfilled exclusively by plant sources. They are synthesized via the Methylerythritol phosphate pathway (MEP) and the Mevalonate pathway (MVA), both existing in plants. The advent of genetic engineering and the latest accomplishments in synthetic biology and metabolic engineering allow microbial synthesis of terpenoids. Cyanobacteria manifest to be the promising hosts for this, utilizing sunlight and CO2. Cyanobacteria possess MEP pathway to generate precursors for terpenoid synthesis. The terpenoid synthesis can be amplified by overexpressing the MEP pathway and engineering MVA pathway genes. According to the desired terpenoid, terpene synthases unique to the plant kingdom must be incorporated in cyanobacteria. Engineering an organism to be used as a cell factory comes with drawbacks such as hampered cell growth and disturbance in metabolic flux. This review set forth a comparison between MEP and MVA pathways, strategies to overexpress these pathways with their challenges.
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Affiliation(s)
- Akhil Rautela
- School of Biochemical Engineering, IIT (BHU), Varanasi, 221005, Uttar Pradesh, India
| | - Sanjay Kumar
- School of Biochemical Engineering, IIT (BHU), Varanasi, 221005, Uttar Pradesh, India.
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16
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Parveen H, Yazdani SS. Insights into cyanobacterial alkane biosynthesis. J Ind Microbiol Biotechnol 2022; 49:kuab075. [PMID: 34718648 PMCID: PMC9118987 DOI: 10.1093/jimb/kuab075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 09/09/2021] [Indexed: 11/12/2022]
Abstract
Alkanes are high-energy molecules that are compatible with enduring liquid fuel infrastructures, which make them highly suitable for being next-generation biofuels. Though biological production of alkanes has been reported in various microorganisms, the reports citing photosynthetic cyanobacteria as natural producers have been the most consistent for the long-chain alkanes and alkenes (C15-C19). However, the production of alkane in cyanobacteria is low, leading to its extraction being uneconomical for commercial purposes. In order to make alkane production economically feasible from cyanobacteria, the titre and yield need to be increased by several orders of magnitude. In the recent past, efforts have been made to enhance alkane production, although with a little gain in yield, leaving space for much improvement. Genetic manipulation in cyanobacteria is considered challenging, but recent advancements in genetic engineering tools may assist in manipulating the genome in order to enhance alkane production. Further, advancement in a basic understanding of metabolic pathways and gene functioning will guide future research for harvesting the potential of these tiny photosynthetically efficient factories. In this review, our focus would be to highlight the current knowledge available on cyanobacterial alkane production, and the potential aspects of developing cyanobacterium as an economical source of biofuel. Further insights into different metabolic pathways and hosts explored so far, and possible challenges in scaling up the production of alkanes will also be discussed.
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Affiliation(s)
- Humaira Parveen
- Microbial Engineering Group, International Centre for Genetic Engineering and Biotechnology, New Delhi 110067 India
| | - Syed Shams Yazdani
- Microbial Engineering Group, International Centre for Genetic Engineering and Biotechnology, New Delhi 110067 India
- DBT-ICGEB Centre for Advanced Bioenergy Research, International Centre for Genetic Engineering and Biotechnology, New Delhi 110067, India
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17
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Hidalgo Martinez D, Betterle N, Melis A. Phycocyanin Fusion Constructs for Heterologous Protein Expression Accumulate as Functional Heterohexameric Complexes in Cyanobacteria. ACS Synth Biol 2022; 11:1152-1166. [PMID: 35257571 DOI: 10.1021/acssynbio.1c00449] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Overexpression of heterologous proteins from plants, bacteria, and human as fusion constructs in cyanobacteria has been documented in the literature. Typically, the heterologous protein "P" of interest is expressed as a fusion with the abundant CpcB β-subunit of phycocyanin (PC), which was placed in the leader sequence position. The working hypothesis for such overexpressions is that CpcB*P fusion proteins somehow accumulate in a soluble and stable form in the cytosol of the cyanobacteria, retaining the activity of the trailing heterologous "P" protein of interest. The present work revealed a substantially different and previously unobvious picture, comprising the following properties of the above-mentioned CpcB*P fusion constructs: (i) the CpcB*P proteins assemble as functional (α,β*P)3CpcG heterohexameric discs, where α is the CpcA α-subunit of PC, β*P is the CpcB*P fusion protein, the asterisk denotes fusion, and CpcG is the 28.9 kDa PC disc linker polypeptide CpcG1. (ii) The (α,β*P)3CpcG1 complexes covalently bind one open tetrapyrrole bilin co-factor per α-subunit and two bilins per β-subunit. (iii) The (α,β*P)3CpcG1 heterohexameric discs are functionally attached to the Synechocystis allophycocyanin (AP) core cylinders and efficiently transfer excitation energy from the assembled (α,β*P)3CpcG1 heterohexamer to the PSII reaction center, enhancing the rate of photochemical charge separation and electron transfer activity in this photosystem. (iv) In addition to the human interferon α-2 and tetanus toxin fragment C tested in this work, we have shown that enzymes such as the plant-origin isoprene synthase, β-phellandrene synthase, geranyl diphosphate synthase, and geranyl linalool synthase are also overexpressed, while retaining their catalytic activity in the respective fusion construct configuration. (v) Folding models for the (α,β*P)3CpcG1 heterohexameric discs showed the recombinant proteins P to be radially oriented with respect to the (α,β)3 compact disc. Elucidation of the fusion construct configuration and function will pave the way for the rational design of fusion constructs harboring and overexpressing multiple proteins of scientific and commercial interest.
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Affiliation(s)
- Diego Hidalgo Martinez
- Plant and Microbial Biology, University of California, Berkeley, California 94720-3102, United States
| | - Nico Betterle
- Plant and Microbial Biology, University of California, Berkeley, California 94720-3102, United States
| | - Anastasios Melis
- Plant and Microbial Biology, University of California, Berkeley, California 94720-3102, United States
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Abstract
Genetic engineering of cyanobacteria is currently limited to genomic integration via homologous recombination and RSF1010-based conjugative vector systems. Here, we introduce a rationally designed conjugative vector with two BioBrick-based cloning sites which enables facilitated and modular cloning. This streamlined vector is suitable for a variety of synthetic biology applications, such as expression of multiple enzymes from metabolic pathways for the production of biofuels or secondary metabolites, or screening of modular parts such as promoters, further facilitating applications to improve crop plants using synthetic biology. Finally, we present a general approach to cloning of constructs, as well as detailed protocols for conjugation and culturing of strains carrying said constructs.
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Affiliation(s)
- Anna Behle
- Department of Biology, Institute for Synthetic Microbiology, Heinrich Heine University, Düsseldorf, Germany
| | - Ilka M Axmann
- Department of Biology, Institute for Synthetic Microbiology, Heinrich Heine University, Düsseldorf, Germany.
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The Molecular Toolset and Techniques Required to Build Cyanobacterial Cell Factories. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2022. [DOI: 10.1007/10_2022_210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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20
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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.
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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.
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21
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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.
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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
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22
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Jin H, Wang Y, Zhao P, Wang L, Zhang S, Meng D, Yang Q, Cheong LZ, Bi Y, Fu Y. Potential of Producing Flavonoids Using Cyanobacteria As a Sustainable Chassis. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2021; 69:12385-12401. [PMID: 34649432 DOI: 10.1021/acs.jafc.1c04632] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Numerous plant secondary metabolites have remarkable impacts on both food supplements and pharmaceuticals for human health improvement. However, higher plants can only generate small amounts of these chemicals with specific temporal and spatial arrangements, which are unable to satisfy the expanding market demands. Cyanobacteria can directly utilize CO2, light energy, and inorganic nutrients to synthesize versatile plant-specific photosynthetic intermediates and organic compounds in large-scale photobioreactors with outstanding economic merit. Thus, they have been rapidly developed as a "green" chassis for the synthesis of bioproducts. Flavonoids, chemical compounds based on aromatic amino acids, are considered to be indispensable components in a variety of nutraceutical, pharmaceutical, and cosmetic applications. In contrast to heterotrophic metabolic engineering pioneers, such as yeast and Escherichia coli, information about the biosynthesis flavonoids and their derivatives is less comprehensive than that of their photosynthetic counterparts. Here, we review both benefits and challenges to promote cyanobacterial cell factories for flavonoid biosynthesis. With increasing concerns about global environmental issues and food security, we are confident that energy self-supporting cyanobacteria will attract increasing attention for the generation of different kinds of bioproducts. We hope that the work presented here will serve as an index and encourage more scientists to join in the relevant research area.
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Affiliation(s)
- Haojie Jin
- College of Forestry, Beijing Forestry University, Beijing 100083, P.R. China
| | - Yan Wang
- Center of Basic Medical Research, Institute of Medical Innovation and Research, Peking University Third Hospital, Beijing 100191, P.R. China
| | - Pengquan Zhao
- College of Forestry, Beijing Forestry University, Beijing 100083, P.R. China
| | - Litao Wang
- College of Forestry, Beijing Forestry University, Beijing 100083, P.R. China
| | - Su Zhang
- College of Forestry, Beijing Forestry University, Beijing 100083, P.R. China
| | - Dong Meng
- College of Forestry, Beijing Forestry University, Beijing 100083, P.R. China
| | - Qing Yang
- College of Forestry, Beijing Forestry University, Beijing 100083, P.R. China
| | - Ling-Zhi Cheong
- Zhejiang-Malaysia Joint Research Laboratory for Agricultural Product Processing and Nutrition, College of Food and Pharmaceutical Science, Ningbo University, Ningbo 315211, China
| | - Yonghong Bi
- State Key Laboratory of Fresh Water Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430070, P.R. China
| | - Yujie Fu
- College of Forestry, Beijing Forestry University, Beijing 100083, P.R. China
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23
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Yadav I, Rautela A, Kumar S. Approaches in the photosynthetic production of sustainable fuels by cyanobacteria using tools of synthetic biology. World J Microbiol Biotechnol 2021; 37:201. [PMID: 34664124 DOI: 10.1007/s11274-021-03157-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Accepted: 09/29/2021] [Indexed: 10/20/2022]
Abstract
Cyanobacteria, photosynthetic prokaryotic microorganisms having a simple genetic composition are the prospective photoautotrophic cell factories for the production of a wide range of biofuel molecules. The simple genetic composition of cyanobacteria allows effortless genetic manipulation which leads to increased research endeavors from the synthetic biology approach. Various unicellular model cyanobacterial strains like Synechocystis sp. PCC 6803 and Synechococcus elongatus PCC 7942 have been successfully engineered for biofuels generation. Improved development of synthetic biology tools, genetic modification methods and advancement in transformation techniques to construct a strain that can contain multiple foreign genes in a single operon have vastly expanded the functions that can be used for engineering photosynthetic cyanobacteria for the generation of various biofuel molecules. In this review, recent advancements and approaches in synthetic biology tools used for cyanobacterial genome editing have been discussed. Apart from this, cyanobacterial productions of various fuel molecules like isoprene, limonene, α-farnesene, squalene, alkanes, butanol, and fatty acids, which can be a substitute for petroleum and fossil fuels in the future, have been elaborated.
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Affiliation(s)
- Indrajeet Yadav
- School of Biochemical Engineering, IIT (BHU) Varanasi, Varanasi, Uttar Pradesh, 221005, India
| | - Akhil Rautela
- School of Biochemical Engineering, IIT (BHU) Varanasi, Varanasi, Uttar Pradesh, 221005, India
| | - Sanjay Kumar
- School of Biochemical Engineering, IIT (BHU) Varanasi, Varanasi, Uttar Pradesh, 221005, India.
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Vavitsas K, Kugler A, Satta A, Hatzinikolaou DG, Lindblad P, Fewer DP, Lindberg P, Toivari M, Stensjö K. Doing synthetic biology with photosynthetic microorganisms. PHYSIOLOGIA PLANTARUM 2021; 173:624-638. [PMID: 33963557 DOI: 10.1111/ppl.13455] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Revised: 04/22/2021] [Accepted: 05/06/2021] [Indexed: 06/12/2023]
Abstract
The use of photosynthetic microbes as synthetic biology hosts for the sustainable production of commodity chemicals and even fuels has received increasing attention over the last decade. The number of studies published, tools implemented, and resources made available for microalgae have increased beyond expectations during the last few years. However, the tools available for genetic engineering in these organisms still lag those available for the more commonly used heterotrophic host organisms. In this mini-review, we provide an overview of the photosynthetic microbes most commonly used in synthetic biology studies, namely cyanobacteria, chlorophytes, eustigmatophytes and diatoms. We provide basic information on the techniques and tools available for each model group of organisms, we outline the state-of-the-art, and we list the synthetic biology tools that have been successfully used. We specifically focus on the latest CRISPR developments, as we believe that precision editing and advanced genetic engineering tools will be pivotal to the advancement of the field. Finally, we discuss the relative strengths and weaknesses of each group of organisms and examine the challenges that need to be overcome to achieve their synthetic biology potential.
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Affiliation(s)
- Konstantinos Vavitsas
- Enzyme and Microbial Biotechnology Unit, Department of Biology, National and Kapodistrian University of Athens, Zografou Campus, Athens, Greece
| | - Amit Kugler
- Microbial Chemistry, Department of Chemistry-Ångström Laboratory, Uppsala University, Uppsala, Sweden
| | - Alessandro Satta
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane, Australia
- CSIRO Synthetic Biology Future Science Platform, Brisbane, Australia
| | - Dimitris G Hatzinikolaou
- Enzyme and Microbial Biotechnology Unit, Department of Biology, National and Kapodistrian University of Athens, Zografou Campus, Athens, Greece
| | - Peter Lindblad
- Microbial Chemistry, Department of Chemistry-Ångström Laboratory, Uppsala University, Uppsala, Sweden
| | - David P Fewer
- Department of Microbiology, University of Helsinki, Helsinki, Finland
| | - Pia Lindberg
- Microbial Chemistry, Department of Chemistry-Ångström Laboratory, Uppsala University, Uppsala, Sweden
| | - Mervi Toivari
- VTT, Technical Research Centre of Finland Ltd, Espoo, Finland
| | - Karin Stensjö
- Microbial Chemistry, Department of Chemistry-Ångström Laboratory, Uppsala University, Uppsala, Sweden
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25
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Ranade S, He Q. Escherichia coli AraJ boosts utilization of arabinose in metabolically engineered cyanobacterium Synechocystis sp. PCC 6803. AMB Express 2021; 11:115. [PMID: 34387784 PMCID: PMC8363721 DOI: 10.1186/s13568-021-01277-7] [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: 08/03/2021] [Accepted: 08/06/2021] [Indexed: 12/02/2022] Open
Abstract
Lignocellulosic biomass can serve as an inexpensive and renewable source of carbon for the biosynthesis of commercially important compounds. L-arabinose is the second most abundant pentose sugar present in the plant materials. Model cyanobacterium Synechocystis sp. PCC 6803 is incapable of catabolism of L-arabinose as a source of carbon and energy. In this study, all the heterologous genes expressed in Synechocystis were derived from Escherichia coli K-12. Initially we constructed four Synechocystis strains that expressed AraBAD enzymes involved in L-arabinose catabolism, either in combination with or without one of the three arabinose transporters, AraE, AraFGH or AraJ. Among the recombinants, the strain possessing AraJ transporter was observed to be the most efficient in terms of dry biomass production and L-arabinose consumption. Later, an additional strain was generated by the expression of AraJ in the AraE-possessing strain. The resultant strain was shown to be advantageous over its parent. This study demonstrates that AraJ, a protein with hitherto unknown function plays a role in the uptake of L-arabinose to boost its catabolism in the transgenic Synechocystis strains. The work also contributes to the current knowledge regarding metabolic engineering of cyanobacteria for the utilization of pentose sugars.
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Zhou J, Yang F, Zhang F, Meng H, Zhang Y, Li Y. Impairing photorespiration increases photosynthetic conversion of CO 2 to isoprene in engineered cyanobacteria. BIORESOUR BIOPROCESS 2021; 8:42. [PMID: 38650280 PMCID: PMC10992918 DOI: 10.1186/s40643-021-00398-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Accepted: 05/17/2021] [Indexed: 11/10/2022] Open
Abstract
Photorespiration consumes fixed carbon and energy generated from photosynthesis to recycle glycolate and dissipate excess energy. The aim of this study was to investigate whether we can use the energy that is otherwise consumed by photorespiration to improve the production of chemicals which requires energy input. To this end, we designed and introduced an isoprene synthetic pathway, which requires ATP and NADPH input, into the cyanobacterium Synechocystis sp. 6803. We then deleted the glcD1 and glcD2 genes which encode glycolate dehydrogenase to impair photorespiration in isoprene-producing strain of Synechocystis. Production of isoprene in glcD1/glcD2 disrupted strain doubled, and stoichiometric analysis indicated that the energy saved from the impaired photorespiration was redirected to increase production of isoprene. Thus, we demonstrate we can use the energy consumed by photorespiration of cyanobacteria to increase the energy-dependent production of chemicals from CO2.
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Affiliation(s)
- Jie Zhou
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, State Key Laboratory of Transducer Technology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Fan Yang
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, No. 1 West Beichen Road, Chaoyang District, Beijing, 100101, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Fuliang Zhang
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, No. 1 West Beichen Road, Chaoyang District, Beijing, 100101, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Hengkai Meng
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, No. 1 West Beichen Road, Chaoyang District, Beijing, 100101, China
- School of Life Sciences, University of Science and Technology of China, Hefei, China
| | - Yanping Zhang
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, No. 1 West Beichen Road, Chaoyang District, Beijing, 100101, China
| | - Yin Li
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, No. 1 West Beichen Road, Chaoyang District, Beijing, 100101, China.
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Meng H, Zhang W, Zhu H, Yang F, Zhang Y, Zhou J, Li Y. Over-expression of an electron transport protein OmcS provides sufficient NADH for D-lactate production in cyanobacterium. BIOTECHNOLOGY FOR BIOFUELS 2021; 14:109. [PMID: 33926521 PMCID: PMC8082822 DOI: 10.1186/s13068-021-01956-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Accepted: 04/12/2021] [Indexed: 06/10/2023]
Abstract
BACKGROUND An efficient supply of reducing equivalent is essential for chemicals production by engineered microbes. In phototrophic microbes, the NADPH generated from photosynthesis is the dominant form of reducing equivalent. However, most dehydrogenases prefer to utilize NADH as a cofactor. Thus, sufficient NADH supply is crucial to produce dehydrogenase-derived chemicals in cyanobacteria. Photosynthetic electron is the sole energy source and excess electrons are wasted in the light reactions of photosynthesis. RESULTS Here we propose a novel strategy to direct the electrons to generate more ATP from light reactions to provide sufficient NADH for lactate production. To this end, we introduced an electron transport protein-encoding gene omcS into cyanobacterium Synechococcus elongatus UTEX 2973 and demonstrated that the introduced OmcS directs excess electrons from plastoquinone (PQ) to photosystem I (PSI) to stimulate cyclic electron transfer (CET). As a result, an approximately 30% increased intracellular ATP, 60% increased intracellular NADH concentrations and up to 60% increased biomass production with fourfold increased D-lactate production were achieved. Comparative transcriptome analysis showed upregulation of proteins involved in linear electron transfer (LET), CET, and downregulation of proteins involved in respiratory electron transfer (RET), giving hints to understand the increased levels of ATP and NADH. CONCLUSIONS This strategy provides a novel orthologous way to improve photosynthesis via enhancing CET and supply sufficient NADH for the photosynthetic production of chemicals.
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Affiliation(s)
- Hengkai Meng
- Department of Cellular Biology, University of Science and Technology of China, Hefei, China
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, No. 1 West Beichen Road, Chaoyang District, Beijing, 100101, China
- State Key Laboratory of Transducer Technology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Wei Zhang
- Department of Cellular Biology, University of Science and Technology of China, Hefei, China
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, No. 1 West Beichen Road, Chaoyang District, Beijing, 100101, China
| | - Huawei Zhu
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, No. 1 West Beichen Road, Chaoyang District, Beijing, 100101, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Fan Yang
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, No. 1 West Beichen Road, Chaoyang District, Beijing, 100101, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Yanping Zhang
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, No. 1 West Beichen Road, Chaoyang District, Beijing, 100101, China
| | - Jie Zhou
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, No. 1 West Beichen Road, Chaoyang District, Beijing, 100101, China.
| | - Yin Li
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, No. 1 West Beichen Road, Chaoyang District, Beijing, 100101, China.
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Gupta JK, Srivastava S. The Effect of Promoter and RBS Combination on the Growth and Glycogen Productivity of Sodium-Dependent Bicarbonate Transporter (SbtA) Overexpressing Synechococcus sp. PCC 7002 Cells. Front Microbiol 2021; 12:607411. [PMID: 33927699 PMCID: PMC8076525 DOI: 10.3389/fmicb.2021.607411] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Accepted: 03/22/2021] [Indexed: 12/20/2022] Open
Abstract
Sodium dependent bicarbonate transporter, SbtA is a high-affinity, inducible bicarbonate transporter in cyanobacterial cells. Our previous work has shown that overexpression of this transporter can significantly increase growth and glycogen accumulation in Synechococcus sp. PCC 7002 cells. In this work, we have tested the effect of two different RBS sequences (RBS1: GGAGGA and RBS2: AGGAGA) and three different promoters (PcpcB, PcpcB560, and PrbcL2) on the growth and glycogen production in SbtA-overexpressing Synechococcus sp. PCC 7002 cells. Our results show that PcpcB or PcpcB560 were more effective than PrbcL2 in increasing the growth and glycogen content. The choice of RBS sequence had relatively minor effect, though RBS2 was more effective than RBS1. The transformant E, with PcpcB560 and RBS2, showed the highest growth. The biomass after 5 days of growth on air or 1% CO2 was increased by about 90% in the strain E compared to PCC 7002 cells. All transformants overexpressing SbtA had higher glycogen content. However, growing the cells with bubbling of 1% CO2 did not increase cellular glycogen content any further. The strain E had about 80% higher glycogen content compared to WT PCC 7002 cells. Therefore, the glycogen productivity of the strain E grown with air-bubbling was about 2.5-fold that of the WT PCC 7002 cells grown similarly. Additionally, some of the transformants had higher chlorophyll content while all the transformants had higher carotenoid content compared to the PCC 7002 cells, suggesting interaction between carbon transport and pigment levels. Thus, this work shows that the choice of photosynthetic promoters and RBSs sequences can impact growth and glycogen accumulation in SbtA-overexpressing cells.
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Affiliation(s)
- Jai Kumar Gupta
- Systems Biology for Biofuels Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi, India
| | - Shireesh Srivastava
- Systems Biology for Biofuels Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi, India.,Department of Biotechnology-International Centre for Genetic Engineering and Biotechnology (DBT-ICGEB), Centre for Advanced Bioenergy Research, New Delhi, India
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Shono C, Ariyanti D, Abe K, Sakai Y, Sakamoto I, Tsukakoshi K, Sode K, Ikebukuro K. A Green Light-Regulated T7 RNA Polymerase Gene Expression System for Cyanobacteria. MARINE BIOTECHNOLOGY (NEW YORK, N.Y.) 2021; 23:31-38. [PMID: 32979137 DOI: 10.1007/s10126-020-09997-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Accepted: 09/10/2020] [Indexed: 06/11/2023]
Abstract
In this study, we developed a green light-regulated T7 RNA polymerase expression system (T7 RNAP system), to provide a novel and versatile high-expression system for cyanobacteria without using any chemical inducer, realizing high expression levels comparable with previously reported for recombinant gene expression in cyanobacteria. The T7 RNAP system was constructed and introduced into Synechocystis sp. PCC6803. T7 RNAP was inserted downstream of the cpcG2 promoter, which is recognized and activated by the CcaS/CcaR two-component green-light-sensing system, to compose a vector plasmid, pKT-CS01, to achieve the induction of T7 RNAP expression only under green light illumination, with repression under red light illumination. The reporter gene, superfolder green fluorescent protein (sfGFP), was inserted downstream of the T7 promoter. Transcriptional analyses revealed that T7 RNAP was induced under green light but repressed under red light. Expression of the sfGFP protein derived from pKT-CS01 was observed under green light illumination and was approximately 10-fold higher than that in the control transformant, which expressed sfGFP directly under the cpcG2 promoter, which is directly regulated by CcaS/CcaR, under green light illumination. Comparison with the strong promoter expression systems Pcpc560 and PtrcΔlacO revealed that the expression of sfGFP by the T7 RNAP system was comparable with the levels obtained with strong promoters. These results demonstrated that the green light-regulated T7 RNAP gene expression system will be a versatile tool for future technological platform to regulate gene expression in cyanobacterial bioprocesses.
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Affiliation(s)
- Chika Shono
- Department of Biotechnology and Life Science, Graduate School of Engineering, Tokyo University of Agriculture and Technology, Koganei, Tokyo, Japan
| | - Dwi Ariyanti
- Department of Biotechnology and Life Science, Graduate School of Engineering, Tokyo University of Agriculture and Technology, Koganei, Tokyo, Japan
- Faculty of Biotechnology, Sumbawa University of Technology, Olat Maras, Moyo Hulu, Sumbawa, West Nusa Tenggara, 84371, Indonesia
| | - Koichi Abe
- Department of Biotechnology and Life Science, Graduate School of Engineering, Tokyo University of Agriculture and Technology, Koganei, Tokyo, Japan
| | - Yuta Sakai
- Department of Biotechnology and Life Science, Graduate School of Engineering, Tokyo University of Agriculture and Technology, Koganei, Tokyo, Japan
| | - Ippei Sakamoto
- Department of Biotechnology and Life Science, Graduate School of Engineering, Tokyo University of Agriculture and Technology, Koganei, Tokyo, Japan
| | - Kaori Tsukakoshi
- Department of Biotechnology and Life Science, Graduate School of Engineering, Tokyo University of Agriculture and Technology, Koganei, Tokyo, Japan
| | - Koji Sode
- Department of Biotechnology and Life Science, Graduate School of Engineering, Tokyo University of Agriculture and Technology, Koganei, Tokyo, Japan.
- Joint Department of Biomedical Engineering, The University of North Carolina at Chapel Hill and North Carolina State University, Chapel Hill, NC, 27599, USA.
| | - Kazunori Ikebukuro
- Department of Biotechnology and Life Science, Graduate School of Engineering, Tokyo University of Agriculture and Technology, Koganei, Tokyo, Japan.
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RNA Interference by Cyanobacterial Feeding Demonstrates the SCSG1 Gene Is Essential for Ciliogenesis during Oral Apparatus Regeneration in Stentor. Microorganisms 2021; 9:microorganisms9010176. [PMID: 33467569 PMCID: PMC7830263 DOI: 10.3390/microorganisms9010176] [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: 12/16/2020] [Revised: 01/11/2021] [Accepted: 01/13/2021] [Indexed: 11/17/2022] Open
Abstract
In the giant ciliate Stentor coeruleus, oral apparatus (OA) regeneration is an experimentally tractable regeneration paradigm that occurs via a series of morphological steps. OA regeneration is thought to be driven by a complex regulatory system that orchestrates the temporal expression of conserved and specific genes. We previously identified a S. coeruleus-specific gene (named SCSG1) that was significantly upregulated during the ciliogenesis stages of OA regeneration, with an expression peak at the stage of the first OA cilia appearance. We established a novel RNA interference (RNAi) method through cyanobacteria Synechocystis sp. PCC6803 feeding in S. coeruleus. The expression of SCSG1 gene was significantly knocked down by using this method and induced abnormal ciliogenesis of OA regeneration in S. coeruleus, suggesting that SCSG1 is essential for OA regeneration in S. coeruleus. This novel RNAi method by cyanobacterial feeding has potential utility for studying other ciliates.
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Uchiyama J, Ito Y, Matsuhashi A, Ichikawa Y, Sambe M, Kitayama S, Yoshino Y, Moriyama A, Kohga H, Ogawa S, Ohta H. Characterization of Sll1558 in environmental stress tolerance of Synechocystis sp. PCC 6803. PHOTOSYNTHESIS RESEARCH 2020; 146:165-174. [PMID: 32424464 DOI: 10.1007/s11120-020-00759-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Accepted: 05/11/2020] [Indexed: 06/11/2023]
Abstract
So far, the molecular mechanisms underlying the acidic-stress responses of plants are complicated and only fragmentally understood. Here, we investigated the mechanisms responsible for acidic-stress acclimation. Previously, DNA microarray analysis identified the sll1558 gene in Synechocystis sp. PCC 6803 (hereafter called Synechocystis 6803) to be upregulated following short-term acid treatment (1 h at pH 3.0). The sll1558 gene encodes uridine diphosphate-glucose pyrophosphorylase (UDP-glucose pyrophosphorylase), which catalyzes the conversion of glucose-1-phosphate into UDP-glucose. We constructed mutant cells for this gene and analyzed their phenotype. The sll1558 gene did not completely segregate in sll1558 mutant cells; thus, Sll1558 is essential for the survival of Synechocystis 6803. Besides, the partially disrupted sll1558 mutant cells were highly sensitive to acidic stress (pH 6.0) as well as other stress conditions (high salt, high osmolality, high/low temperature, and ultraviolet-B stress); the number of sll1558 transcripts increased under these conditions. UDP-glucose is used for the synthesis of various materials, such as glycolipids. From the membrane lipid composition analysis, digalactosyldiacylglycerol decreased and phosphatidylglycerol increased in the partially disrupted sll1558 mutant cells under acidic stress. These results suggest that sll1558 is important not only for the survival of Synechocystis 6803, but also for tolerance under various stress conditions.
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Affiliation(s)
- Junji Uchiyama
- Department of Biology, Faculty of Science, Tokyo University of Science, Shinjuku-ku, Tokyo, 162-8601, Japan.
- Graduate School of Mathematics and Science Education, Tokyo University of Science, Shinjuku-ku, Tokyo, 162-8601, Japan.
| | - Yutaro Ito
- Department of Biological Science and Technology, Tokyo University of Science, Katsushika-ku, Tokyo, 125-8585, Japan
| | - Ayumi Matsuhashi
- Graduate School of Mathematics and Science Education, Tokyo University of Science, Shinjuku-ku, Tokyo, 162-8601, Japan
| | - Yuta Ichikawa
- Graduate School of Mathematics and Science Education, Tokyo University of Science, Shinjuku-ku, Tokyo, 162-8601, Japan
| | - Mamoru Sambe
- Graduate School of Mathematics and Science Education, Tokyo University of Science, Shinjuku-ku, Tokyo, 162-8601, Japan
| | - Shuichi Kitayama
- Graduate School of Mathematics and Science Education, Tokyo University of Science, Shinjuku-ku, Tokyo, 162-8601, Japan
| | - Yuka Yoshino
- Graduate School of Mathematics and Science Education, Tokyo University of Science, Shinjuku-ku, Tokyo, 162-8601, Japan
| | - Atushi Moriyama
- Graduate School of Mathematics and Science Education, Tokyo University of Science, Shinjuku-ku, Tokyo, 162-8601, Japan
| | - Hidetaka Kohga
- Graduate School of Mathematics and Science Education, Tokyo University of Science, Shinjuku-ku, Tokyo, 162-8601, Japan
| | - Satoru Ogawa
- Laboratory of Electron Microscopy, School of Medicine, Mie University, Tsu, Mie, 514-8507, Japan
| | - Hisataka Ohta
- Department of Biology, Faculty of Science, Tokyo University of Science, Shinjuku-ku, Tokyo, 162-8601, Japan
- Graduate School of Mathematics and Science Education, Tokyo University of Science, Shinjuku-ku, Tokyo, 162-8601, Japan
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32
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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]
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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.
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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
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34
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Diao J, Song X, Zhang L, Cui J, Chen L, Zhang W. Tailoring cyanobacteria as a new platform for highly efficient synthesis of astaxanthin. Metab Eng 2020; 61:275-287. [DOI: 10.1016/j.ymben.2020.07.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Revised: 07/07/2020] [Accepted: 07/07/2020] [Indexed: 01/11/2023]
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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.
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36
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Behle A, Saake P, Germann AT, Dienst D, Axmann IM. Comparative Dose-Response Analysis of Inducible Promoters in Cyanobacteria. ACS Synth Biol 2020; 9:843-855. [PMID: 32134640 DOI: 10.1021/acssynbio.9b00505] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Design and implementation of synthetic biological circuits highly depends on well-characterized, robust promoters with predictable input-output responses. While great progress has been made with heterotrophic model organisms such as Escherichia coli, the available variety of tunable promoter parts for phototrophic cyanobacteria is still limited. Commonly used synthetic and semisynthetic promoters show weak dynamic ranges or no regulation at all in cyanobacterial models. Well-controlled alternatives such as native metal-responsive promoters, however, pose the problems of inducer toxicity and lacking orthogonality. Here, we present the comparative assessment of dose-response functions of four different inducible promoter systems in the model cyanobacterium Synechocystis sp. PCC 6803. Using the novel bimodular reporter plasmid pSHDY, dose-response dynamics of the re-established vanillate-inducible promoter PvanCC was compared to the previously described rhamnose-inducible Prha, the anhydrotetracycline-inducible PL03, and the Co2+-inducible PcoaT. We estimate individual advantages and disadvantages regarding dynamic range and strength of each promoter, also in comparison with well-established constitutive systems. We observed a delicate balance between transcription factor toxicity and sufficient expression to obtain a dose-dependent response to the inducer. In summary, we expand the current understanding and employability of inducible promoters in cyanobacteria, facilitating the scalability and robustness of synthetic regulatory network designs and of complex metabolic pathway engineering strategies.
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Affiliation(s)
- Anna Behle
- Institute for Synthetic Microbiology, Heinrich Heine University Duesseldorf, 40225 Duesseldorf, Germany
| | - Pia Saake
- Institute for Synthetic Microbiology, Heinrich Heine University Duesseldorf, 40225 Duesseldorf, Germany
| | - Anna T. Germann
- Institute for Synthetic Microbiology, Heinrich Heine University Duesseldorf, 40225 Duesseldorf, Germany
| | - Dennis Dienst
- Department of Chemistry − Ångström, Uppsala University, 75120 Uppsala, Sweden
| | - Ilka M. Axmann
- Institute for Synthetic Microbiology, Heinrich Heine University Duesseldorf, 40225 Duesseldorf, Germany
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37
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Fabris M, Abbriano RM, Pernice M, Sutherland DL, Commault AS, Hall CC, Labeeuw L, McCauley JI, Kuzhiuparambil U, Ray P, Kahlke T, Ralph PJ. Emerging Technologies in Algal Biotechnology: Toward the Establishment of a Sustainable, Algae-Based Bioeconomy. FRONTIERS IN PLANT SCIENCE 2020; 11:279. [PMID: 32256509 PMCID: PMC7090149 DOI: 10.3389/fpls.2020.00279] [Citation(s) in RCA: 102] [Impact Index Per Article: 25.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Accepted: 02/24/2020] [Indexed: 05/18/2023]
Abstract
Mankind has recognized the value of land plants as renewable sources of food, medicine, and materials for millennia. Throughout human history, agricultural methods were continuously modified and improved to meet the changing needs of civilization. Today, our rapidly growing population requires further innovation to address the practical limitations and serious environmental concerns associated with current industrial and agricultural practices. Microalgae are a diverse group of unicellular photosynthetic organisms that are emerging as next-generation resources with the potential to address urgent industrial and agricultural demands. The extensive biological diversity of algae can be leveraged to produce a wealth of valuable bioproducts, either naturally or via genetic manipulation. Microalgae additionally possess a set of intrinsic advantages, such as low production costs, no requirement for arable land, and the capacity to grow rapidly in both large-scale outdoor systems and scalable, fully contained photobioreactors. Here, we review technical advancements, novel fields of application, and products in the field of algal biotechnology to illustrate how algae could present high-tech, low-cost, and environmentally friendly solutions to many current and future needs of our society. We discuss how emerging technologies such as synthetic biology, high-throughput phenomics, and the application of internet of things (IoT) automation to algal manufacturing technology can advance the understanding of algal biology and, ultimately, drive the establishment of an algal-based bioeconomy.
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Affiliation(s)
- Michele Fabris
- Climate Change Cluster (C3), University of Technology Sydney, Ultimo, NSW, Australia
- CSIRO Synthetic Biology Future Science Platform, Brisbane, QLD, Australia
| | - Raffaela M. Abbriano
- Climate Change Cluster (C3), University of Technology Sydney, Ultimo, NSW, Australia
| | - Mathieu Pernice
- Climate Change Cluster (C3), University of Technology Sydney, Ultimo, NSW, Australia
| | - Donna L. Sutherland
- Climate Change Cluster (C3), University of Technology Sydney, Ultimo, NSW, Australia
| | - Audrey S. Commault
- Climate Change Cluster (C3), University of Technology Sydney, Ultimo, NSW, Australia
| | - Christopher C. Hall
- Climate Change Cluster (C3), University of Technology Sydney, Ultimo, NSW, Australia
| | - Leen Labeeuw
- Climate Change Cluster (C3), University of Technology Sydney, Ultimo, NSW, Australia
| | - Janice I. McCauley
- Climate Change Cluster (C3), University of Technology Sydney, Ultimo, NSW, Australia
| | | | - Parijat Ray
- Climate Change Cluster (C3), University of Technology Sydney, Ultimo, NSW, Australia
| | - Tim Kahlke
- Climate Change Cluster (C3), University of Technology Sydney, Ultimo, NSW, Australia
| | - Peter J. Ralph
- Climate Change Cluster (C3), University of Technology Sydney, Ultimo, NSW, Australia
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38
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Betterle N, Hidalgo Martinez D, Melis A. Cyanobacterial Production of Biopharmaceutical and Biotherapeutic Proteins. FRONTIERS IN PLANT SCIENCE 2020; 11:237. [PMID: 32194609 PMCID: PMC7062967 DOI: 10.3389/fpls.2020.00237] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Accepted: 02/14/2020] [Indexed: 06/10/2023]
Abstract
Efforts to express human therapeutic proteins in photosynthetic organisms have been described in the literature. Regarding microalgae, most of the research entailed a heterologous transformation of the chloroplast, but transformant cells failed to accumulate the desired recombinant proteins in high quantity. The present work provides methods and DNA construct formulations for over-expressing in photosynthetic cyanobacteria, at the protein level, human-origin bio-pharmaceutical and bio-therapeutic proteins. Proof-of-concept evidence is provided for the design and reduction to practice of "fusion constructs as protein overexpression vectors" for the generation of the bio-therapeutic protein interferon alpha-2 (IFN). IFN is a member of the Type I interferon cytokine family, well-known for its antiviral and anti-proliferative functions. Fusion construct formulations enabled accumulation of IFN up to 12% of total cellular protein in soluble form. In addition, the work reports on the isolation and purification of the fusion IFN protein and preliminary verification of its antiviral activity. Combining the expression and purification protocols developed here, it is possible to produce fairly large quantities of interferon in these photosynthetic microorganisms, generated from sunlight, CO2, and H2O.
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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.
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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.
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Photosynthetic conversion of CO2 to hyaluronic acid by engineered strains of the cyanobacterium Synechococcus sp. PCC 7002. ALGAL RES 2019. [DOI: 10.1016/j.algal.2019.101702] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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Chakravarty D, Banerjee M, Ballal A. Facile generation of a biotechnologically-relevant catalase showcases the efficacy of a blue-green algal biomass as a suitable bioresource for protein overproduction. BIORESOURCE TECHNOLOGY 2019; 293:122013. [PMID: 31494434 DOI: 10.1016/j.biortech.2019.122013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Revised: 08/11/2019] [Accepted: 08/12/2019] [Indexed: 06/10/2023]
Abstract
Here, we show the utility of a cyanobacterial biomass for overproduction and easy downstream processing of the thermostable protein KatB (a Mn-catalase). The nitrogen-fixing blue-green alga, Anabaena, was bioengineered to overexpress the KatB protein (An-KatB). Interestingly, pure An-KatB could be isolated from Anabaena by a simple physical process, obviating the need of expensive resins or chromatographic steps. An-KatB was an efficient H2O2-detoxifying protein that retained all the properties of Mn-catalases. Surprisingly, the purified An-KatB showed improved characteristics than the corresponding KatB (Ec-KatB) protein purified after over-expression in E. coli. An-KatB was unaffected by exposure to high temperature (85 °C), whereas a commercially procured heme-catalase showed an appreciable drop in activity beyond 50 °C. These data convincingly demonstrate the utility of Anabaena as a competent microbial bioresource for overproduction of proteins and further highlight the advantage of An-KatB over heme-catalases in bioprocesses where H2O2 is to be decomposed at elevated temperatures.
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Affiliation(s)
- Dhiman Chakravarty
- Molecular Biology Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085, India; Homi Bhabha National Institute, Anushaktinagar, Mumbai 400094, India
| | - Manisha Banerjee
- Molecular Biology Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085, India; Homi Bhabha National Institute, Anushaktinagar, Mumbai 400094, India
| | - Anand Ballal
- Molecular Biology Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085, India; Homi Bhabha National Institute, Anushaktinagar, Mumbai 400094, India.
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Pauly M, Gawenda N, Wagner C, Fischbach P, Ramírez V, Axmann IM, Voiniciuc C. The Suitability of Orthogonal Hosts to Study Plant Cell Wall Biosynthesis. PLANTS (BASEL, SWITZERLAND) 2019; 8:E516. [PMID: 31744209 PMCID: PMC6918405 DOI: 10.3390/plants8110516] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Revised: 11/08/2019] [Accepted: 11/15/2019] [Indexed: 12/20/2022]
Abstract
Plant cells are surrounded by an extracellular matrix that consists mainly of polysaccharides. Many molecular components involved in plant cell wall polymer synthesis have been identified, but it remains largely unknown how these molecular players function together to define the length and decoration pattern of a polysaccharide. Synthetic biology can be applied to answer questions beyond individual glycosyltransferases by reconstructing entire biosynthetic machineries required to produce a complete wall polysaccharide. Recently, this approach was successful in establishing the production of heteromannan from several plant species in an orthogonal host-a yeast-illuminating the role of an auxiliary protein in the biosynthetic process. In this review we evaluate to what extent a selection of organisms from three kingdoms of life (Bacteria, Fungi and Animalia) might be suitable for the synthesis of plant cell wall polysaccharides. By identifying their key attributes for glycoengineering as well as analyzing the glycosidic linkages of their native polymers, we present a valuable comparison of their key advantages and limitations for the production of different classes of plant polysaccharides.
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Affiliation(s)
- Markus Pauly
- Institute for Plant Cell Biology and Biotechnology, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany; (M.P.); (N.G.); (V.R.)
| | - Niklas Gawenda
- Institute for Plant Cell Biology and Biotechnology, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany; (M.P.); (N.G.); (V.R.)
| | - Christine Wagner
- Independent Junior Research Group–Designer Glycans, Leibniz Institute of Plant Biochemistry, 06120 Halle (Saale), Germany;
| | - Patrick Fischbach
- Institute of Synthetic Biology, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany;
| | - Vicente Ramírez
- Institute for Plant Cell Biology and Biotechnology, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany; (M.P.); (N.G.); (V.R.)
| | - Ilka M. Axmann
- Institute for Synthetic Microbiology, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany;
| | - Cătălin Voiniciuc
- Independent Junior Research Group–Designer Glycans, Leibniz Institute of Plant Biochemistry, 06120 Halle (Saale), Germany;
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Development of a longevous two-species biophotovoltaics with constrained electron flow. Nat Commun 2019; 10:4282. [PMID: 31537786 PMCID: PMC6753107 DOI: 10.1038/s41467-019-12190-w] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2019] [Accepted: 08/27/2019] [Indexed: 01/07/2023] Open
Abstract
Microbial biophotovoltaics (BPV) offers a biological solution for renewable energy production by using photosynthetic microorganisms as light absorbers. Although abiotic engineering approaches, e.g., electrode modification and device optimization, can enhance the electrochemical communication between living cells and electrodes, the power densities of BPV are still low due to the weak exoelectrogenic activity of photosynthetic microorganisms. Here, we develop a BPV based on a D-lactate mediated microbial consortium consisting of photosynthetic cyanobacteria and exoelectrogenic Shewanella. By directing solar energy from photons to D-lactate, then to electricity, this BPV generates a power density of over 150 mW·m-2 in a temporal separation setup. Furthermore, a spatial-temporal separation setup with medium replenishment enables stable operation for over 40 days with an average power density of 135 mW·m-2. These results demonstrate the electron flow constrained microbial consortium can facilitate electron export from photosynthetic cells and achieve an efficient and durable power output.
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Evaluation of New Genetic Toolkits and Their Role for Ethanol Production in Cyanobacteria. ENERGIES 2019. [DOI: 10.3390/en12183515] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Since the public awareness for climate change has risen, increasing scientific effort has been made to find and develop alternative resources and production processes to reduce the dependency on petrol-based fuels and chemicals of our society. Among others, the biotechnological fuel production, as for example fermenting sugar-rich crops to ethanol, is one of the main strategies. For this purpose, various classical production systems like Escherichia coli or Saccharomyces cerevisiae are used and have been optimized via genetic modifications. Despite the progress made, this strategy competes for nutritional resources and agricultural land. To overcome this problem, various attempts were made for direct photosynthetic driven ethanol synthesis with different microalgal species including cyanobacteria. However, compared to existing platforms, the development of cyanobacteria as photoautotrophic cell factories has just started, and accordingly, the ethanol yield of established production systems is still unreached. This is mainly attributed to low ethanol tolerance levels of cyanobacteria and there is still potential for optimizing the cyanobacteria towards alternative gene expression systems. Meanwhile, several improvements were made by establishing new toolboxes for synthetic biology offering new possibilities for advanced genetic modifications of cyanobacteria. Here, current achievements and innovations of those new molecular tools are discussed.
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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.
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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
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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.
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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.
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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
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Shen G, Canniffe DP, Ho MY, Kurashov V, van der Est A, Golbeck JH, Bryant DA. Characterization of chlorophyll f synthase heterologously produced in Synechococcus sp. PCC 7002. PHOTOSYNTHESIS RESEARCH 2019; 140:77-92. [PMID: 30607859 DOI: 10.1007/s11120-018-00610-9] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2018] [Accepted: 12/17/2018] [Indexed: 05/19/2023]
Abstract
In diverse terrestrial cyanobacteria, Far-Red Light Photoacclimation (FaRLiP) promotes extensive remodeling of the photosynthetic apparatus, including photosystems (PS)I and PSII and the cores of phycobilisomes, and is accompanied by the concomitant biosynthesis of chlorophyll (Chl) d and Chl f. Chl f synthase, encoded by chlF, is a highly divergent paralog of psbA; heterologous expression of chlF from Chlorogloeopsis fritscii PCC 9212 led to the light-dependent production of Chl f in Synechococcus sp. PCC 7002 (Ho et al., Science 353, aaf9178 (2016)). In the studies reported here, expression of the chlF gene from Fischerella thermalis PCC 7521 in the heterologous system led to enhanced synthesis of Chl f. N-terminally [His]10-tagged ChlF7521 was purified and identified by immunoblotting and tryptic-peptide mass fingerprinting. As predicted from its sequence similarity to PsbA, ChlF bound Chl a and pheophytin a at a ratio of ~ 3-4:1, bound β-carotene and zeaxanthin, and was inhibited in vivo by 3-(3,4-dichlorophenyl)-1,1-dimethylurea. Cross-linking studies and the absence of copurifying proteins indicated that ChlF forms homodimers. Flash photolysis of ChlF produced a Chl a triplet that decayed with a lifetime (1/e) of ~ 817 µs and that could be attributed to intersystem crossing by EPR spectroscopy at 90 K. When the chlF7521 gene was expressed in a strain in which the psbD1 and psbD2 genes had been deleted, significantly more Chl f was produced, and Chl f levels could be further enhanced by specific growth-light conditions. Chl f synthesized in Synechococcus sp. PCC 7002 was inserted into trimeric PSI complexes.
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Affiliation(s)
- Gaozhong Shen
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Daniel P Canniffe
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, 16802, USA
- Department of Molecular Biology & Biotechnology, University of Sheffield, Sheffield, S10 2TN, UK
| | - Ming-Yang Ho
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Vasily Kurashov
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Art van der Est
- Department of Chemistry, Brock University, St. Catharines, ON, L2S 3A1, Canada
| | - John H Golbeck
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, 16802, USA
- Department of Chemistry, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Donald A Bryant
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, 16802, USA.
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT, 59717, USA.
- S-002 Frear Laboratory, Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, 16802, USA.
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Machida S, Suzuki I. Characterization of cyanobacterial cells synthesizing 10-methyl stearic acid. PHOTOSYNTHESIS RESEARCH 2019; 139:173-183. [PMID: 29943360 DOI: 10.1007/s11120-018-0537-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Accepted: 06/15/2018] [Indexed: 06/08/2023]
Abstract
Recently, microalgae have attracted attention as sources of biomass energy. However, fatty acids from the microalgae are mainly unsaturated and show low stability in oxygenated environments, due to oxidation of the double bonds. The branched-chain fatty acid, 10-methyl stearic acid, is synthesized from oleic acid in certain bacteria; the fatty acid is saturated, but melting point is low. Thus, it is stable in the presence of oxygen and is highly fluid. We previously demonstrated that BfaA and BfaB in Mycobacterium chlorophenolicum are involved in the synthesis of 10-methyl stearic acid from oleic acid. In this study, as a consequence of the introduction of bfaA and bfaB into the cyanobacterium, Synechocystis sp. PCC 6803, we succeeded in producing 10-methyl stearic acid, with yields up to 4.1% of the total fatty acid content. The synthesis of 10-methyl stearic acid in Synechocystis cells did not show a significant effect on photosynthetic activity, but the growth of the cells was retarded at 34 °C. We observed that the synthesis of 10-methylene stearic acid, a precursor of 10-methyl stearic acid, had an inhibitory effect on the growth of the transformants, which was mitigated under microoxic conditions. Eventually, the amount of 10-methyl stearic acid present in the sulfoquinovosyl diacylglycerol and phosphatidylglycerol of the transformants was remarkably higher than that in the monogalactosyldiacylglycerol and digalactosyldiacylglycerol. Overall, we successfully synthesized 10-methyl stearic acid in the phototroph, Synechocystis, demonstrating that it is possible to synthesize unique modified fatty acids via photosynthesis that are not naturally produced in photosynthetic organisms.
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Affiliation(s)
- Shuntaro Machida
- Graduate School of Life and Environmental Sciences, University of Tsukuba, Tennodai 1-1-1, Tsukuba, Ibaraki, 305-8572, Japan
- Food Research Institute, National Agriculture and Food Research Organization, Kannondai 2-1-12, Tsukuba, Ibaraki, 305-8642, Japan
| | - Iwane Suzuki
- Faculty of Life and Environmental Sciences, University of Tsukuba, Tennodai 1-1-1, Tsukuba, Ibaraki, 305-8572, Japan.
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Santos-Merino M, Singh AK, Ducat DC. New Applications of Synthetic Biology Tools for Cyanobacterial Metabolic Engineering. Front Bioeng Biotechnol 2019; 7:33. [PMID: 30873404 PMCID: PMC6400836 DOI: 10.3389/fbioe.2019.00033] [Citation(s) in RCA: 114] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Accepted: 02/05/2019] [Indexed: 01/25/2023] Open
Abstract
Cyanobacteria are promising microorganisms for sustainable biotechnologies, yet unlocking their potential requires radical re-engineering and application of cutting-edge synthetic biology techniques. In recent years, the available devices and strategies for modifying cyanobacteria have been increasing, including advances in the design of genetic promoters, ribosome binding sites, riboswitches, reporter proteins, modular vector systems, and markerless selection systems. Because of these new toolkits, cyanobacteria have been successfully engineered to express heterologous pathways for the production of a wide variety of valuable compounds. Cyanobacterial strains with the potential to be used in real-world applications will require the refinement of genetic circuits used to express the heterologous pathways and development of accurate models that predict how these pathways can be best integrated into the larger cellular metabolic network. Herein, we review advances that have been made to translate synthetic biology tools into cyanobacterial model organisms and summarize experimental and in silico strategies that have been employed to increase their bioproduction potential. Despite the advances in synthetic biology and metabolic engineering during the last years, it is clear that still further improvements are required if cyanobacteria are to be competitive with heterotrophic microorganisms for the bioproduction of added-value compounds.
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Affiliation(s)
- María Santos-Merino
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI, United States
| | - Amit K. Singh
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI, United States
| | - Daniel C. Ducat
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI, United States
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI, United States
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