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Sakamaki Y, Maeda K, Nimura-Matsune K, Chibazakura T, Watanabe S. Characterization of a cyanobacterial rep protein with broad-host range and its utilization for expression vectors. Front Microbiol 2023; 14:1111979. [PMID: 37032853 PMCID: PMC10079941 DOI: 10.3389/fmicb.2023.1111979] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Accepted: 02/27/2023] [Indexed: 04/11/2023] Open
Abstract
Owing to their photosynthetic capabilities, cyanobacteria are regarded as ecologically friendly hosts for production of biomaterials. However, compared to other bacteria, tools for genetic engineering, especially expression vector systems, are limited. In this study, we characterized a Rep protein, exhibiting replication activity in multiple cyanobacteria and established an expression vector using this protein. Our comprehensive screening using a genomic library of Synechocystis sp. PCC 6803 revealed that a certain region encoding a Rep-related protein (here named Cyanobacterial Rep protein A2: CyRepA2) exhibits high autonomous replication activity in a heterologous host cyanobacterium, Synechococcus elongatus PCC 7942. A reporter assay using GFP showed that the expression vector pYS carrying CyRepA2 can be maintained in not only S. 6803 and S. 7942, but also Synechococcus sp. PCC 7002 and Anabaena sp. PCC 7120. In S. 7942, GFP expression in the pYS-based system was tightly regulated by IPTG, achieving 10-fold higher levels than in the chromosome-based system. Furthermore, pYS could be used together with the conventional vector pEX, which was constructed from an endogenous plasmid in S. 7942. The combination of pYS with other vectors is useful for genetic engineering, such as modifying metabolic pathways, and is expected to improve the performance of cyanobacteria as bioproduction chassis.
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Affiliation(s)
- Yutaka Sakamaki
- Department of Bioscience, Tokyo University of Agriculture, Tokyo, Japan
| | - Kaisei Maeda
- Department of Bioscience, Tokyo University of Agriculture, Tokyo, Japan
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, Yokohama, Japan
| | | | - Taku Chibazakura
- Department of Bioscience, Tokyo University of Agriculture, Tokyo, Japan
| | - Satoru Watanabe
- Department of Bioscience, Tokyo University of Agriculture, Tokyo, Japan
- *Correspondence: Satoru Watanabe,
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2
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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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3
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Bertram R, Neumann B, Schuster CF. Status quo of tet regulation in bacteria. Microb Biotechnol 2021; 15:1101-1119. [PMID: 34713957 PMCID: PMC8966031 DOI: 10.1111/1751-7915.13926] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Revised: 09/02/2021] [Accepted: 09/04/2021] [Indexed: 11/27/2022] Open
Abstract
The tetracycline repressor (TetR) belongs to the most popular, versatile and efficient transcriptional regulators used in bacterial genetics. In the tetracycline (Tc) resistance determinant tet(B) of transposon Tn10, tetR regulates the expression of a divergently oriented tetA gene that encodes a Tc antiporter. These components of Tn10 and of other natural or synthetic origins have been used for tetracycline‐dependent gene regulation (tet regulation) in at least 40 bacterial genera. Tet regulation serves several purposes such as conditional complementation, depletion of essential genes, modulation of artificial genetic networks, protein overexpression or the control of gene expression within cell culture or animal infection models. Adaptations of the promoters employed have increased tet regulation efficiency and have made this system accessible to taxonomically distant bacteria. Variations of TetR, different effector molecules and mutated DNA binding sites have enabled new modes of gene expression control. This article provides a current overview of tet regulation in bacteria.
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Affiliation(s)
- Ralph Bertram
- Institute of Clinical Hygiene, Medical Microbiology and Infectiology, Paracelsus Medical University, Prof.-Ernst-Nathan-Straße 1, Nuremberg, 90419, Germany
| | - Bernd Neumann
- Institute of Clinical Hygiene, Medical Microbiology and Infectiology, Paracelsus Medical University, Prof.-Ernst-Nathan-Straße 1, Nuremberg, 90419, Germany
| | - Christopher F Schuster
- Department of Infectious Diseases, Division of Nosocomial Pathogens and Antibiotic Resistances, Robert Koch Institute, Burgstraße 37, Wernigerode, 38855, Germany
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4
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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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Real-time monitoring of the in vivo redox state transition using the ratiometric redox state sensor protein FROG/B. Proc Natl Acad Sci U S A 2020; 117:16019-16026. [PMID: 32576684 DOI: 10.1073/pnas.1918919117] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
The intracellular redox state is one of the key factors regulating various physiological phenomena in the cell. Monitoring this state is therefore important for understanding physiological homeostasis in cells. Various fluorescent sensor proteins have already been developed to monitor intracellular redox state. We also developed fluorescent redox sensor proteins named Oba-Q and Re-Q, the emissions of which are quenched under oxidized and reduced conditions, respectively. Although these sensors were useful to visualize the redox changes in the cell over time, they have the weakness that their emission signals are directly influenced by their in situ expression levels. To overcome this problem, we developed a redox sensor protein with a single excitation peak and dual variable emission peaks. This sensor protein shows green emission under oxidized conditions and blue emission under reduced conditions. We therefore named this sensor FROG/B, fluorescent protein with redox-dependent change in green/blue. By using this sensor, we successfully measured the changes in intracellular redox potentials in cyanobacterial cells quantitatively caused by light/dark transition just by calculating the ratio of emission between green and blue signals.
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6
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Mihara S, Sugiura K, Yoshida K, Hisabori T. Thioredoxin targets are regulated in heterocysts of cyanobacterium Anabaena sp. PCC 7120 in a light-independent manner. JOURNAL OF EXPERIMENTAL BOTANY 2020; 71:2018-2027. [PMID: 31863668 PMCID: PMC7242069 DOI: 10.1093/jxb/erz561] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Accepted: 12/18/2019] [Indexed: 05/22/2023]
Abstract
In the nitrogen-fixing cyanobacterium Anabaena sp. PCC 7120, glucose 6-phosphate dehydrogenase (G6PDH) plays an important role in producing the power for reducing nitrogenase under light conditions. Our previous study showed that thioredoxin suppresses G6PDH by reducing its activator protein OpcA, implying that G6PDH is inactivated under light conditions because thioredoxins are reduced by the photosynthetic electron transport system in cyanobacteria. To address how Anabaena sp. PCC 7120 maintains G6PDH activity even under light conditions when nitrogen fixation occurs, we investigated the redox regulation system in vegetative cells and specific nitrogen-fixing cells named heterocysts, individually. We found that thioredoxin target proteins were more oxidized in heterocysts than in vegetative cells under light conditions. Alterations in the redox regulation mechanism of heterocysts may affect the redox states of thioredoxin target proteins, including OpcA, so that G6PDH is activated in heterocysts even under light conditions.
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Affiliation(s)
- Shoko Mihara
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, Nagatsuta-cho, Midori-ku, Yokohama, Japan
| | - Kazunori Sugiura
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, Nagatsuta-cho, Midori-ku, Yokohama, Japan
- School of Life Science and Technology, Tokyo Institute of Technology, Nagatsuta-cho, Midori-ku, Yokohama, Japan
- Present address: The Institute of Scientific and Industrial Research, Osaka University, Ibaraki, Osaka 567-0047, Japan
| | - Keisuke Yoshida
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, Nagatsuta-cho, Midori-ku, Yokohama, Japan
- School of Life Science and Technology, Tokyo Institute of Technology, Nagatsuta-cho, Midori-ku, Yokohama, Japan
| | - Toru Hisabori
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, Nagatsuta-cho, Midori-ku, Yokohama, Japan
- School of Life Science and Technology, Tokyo Institute of Technology, Nagatsuta-cho, Midori-ku, Yokohama, Japan
- Correspondence:
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7
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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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8
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Cook TB, Pfleger BF. Leveraging synthetic biology for producing bioactive polyketides and non-ribosomal peptides in bacterial heterologous hosts. MEDCHEMCOMM 2019; 10:668-681. [PMID: 31191858 PMCID: PMC6540960 DOI: 10.1039/c9md00055k] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Accepted: 04/06/2019] [Indexed: 12/14/2022]
Abstract
Bacteria have historically been a rich source of natural products (e.g. polyketides and non-ribosomal peptides) that possess medically-relevant activities. Despite extensive discovery programs in both industry and academia, a plethora of biosynthetic pathways remain uncharacterized and the corresponding molecular products untested for potential bioactivities. This knowledge gap comes in part from the fact that many putative natural product producers have not been cultured in conventional laboratory settings in which the corresponding products are produced at detectable levels. Next-generation sequencing technologies are further increasing the knowledge gap by obtaining metagenomic sequence information from complex communities where production of the desired compound cannot be isolated in the laboratory. For these reasons, many groups are turning to synthetic biology to produce putative natural products in heterologous hosts. This strategy depends on the ability to heterologously express putative biosynthetic gene clusters and produce relevant quantities of the corresponding products. Actinobacteria remain the most abundant source of natural products and the most promising heterologous hosts for natural product discovery and production. However, researchers are discovering more natural products from other groups of bacteria, such as myxobacteria and cyanobacteria. Therefore, phylogenetically similar heterologous hosts have become promising candidates for synthesizing these novel molecules. The downside of working with these microbes is the lack of well-characterized genetic tools for optimizing expression of gene clusters and product titers. This review examines heterologous expression of natural product gene clusters in terms of the motivations for this research, the traits desired in an ideal host, tools available to the field, and a survey of recent progress.
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Affiliation(s)
- Taylor B Cook
- Department of Chemical and Biological Engineering , University of Wisconsin-Madison , 1415 Engineering Dr. Room 3629 , Madison , WI 53706 , USA .
| | - Brian F Pfleger
- Department of Chemical and Biological Engineering , University of Wisconsin-Madison , 1415 Engineering Dr. Room 3629 , Madison , WI 53706 , USA .
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9
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Higo A, Ehira S. Spatiotemporal Gene Repression System in the Heterocyst-Forming Multicellular Cyanobacterium Anabaena sp. PCC 7120. ACS Synth Biol 2019; 8:641-646. [PMID: 30865823 DOI: 10.1021/acssynbio.8b00496] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The heterocyst-forming multicellular cyanobacterium Anabaena sp. PCC 7120 is often used as a model organism for prokaryotic cell differentiation. We recently demonstrated that heterocysts are suitable for photosynthetic production of valuable chemicals, such as ethanol, due to their active catabolism and microoxic conditions. We have developed gene regulation systems, including cell type-specific gene induction systems, to broaden this cyanobacterium's use. In the present study, a heterocyst-specific conditional gene repression system was successfully created by combining a cell type-specific gene induction system with CRISPRi technology. We targeted the gln A gene that encodes glutamine synthetase, an essential enzyme for nitrogen assimilation, to reconstruct metabolism in the multicellular cyanobacterium. Heterocyst-specific repression of gln A enhanced ethanol production. We believe that heterocyst-specific gene repression systems are useful tools for basic research on cell differentiation as well as for metabolic engineering of heterocysts.
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Affiliation(s)
- Akiyoshi Higo
- Department of Biological Sciences, Graduate School of Science, Tokyo Metropolitan University, 1-1 Minami-Osawa, Hachioji, Tokyo 192-0397, Japan
| | - Shigeki Ehira
- Department of Biological Sciences, Graduate School of Science, Tokyo Metropolitan University, 1-1 Minami-Osawa, Hachioji, Tokyo 192-0397, Japan
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10
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Gordon GC, Pfleger BF. Regulatory Tools for Controlling Gene Expression in Cyanobacteria. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1080:281-315. [PMID: 30091100 PMCID: PMC6662922 DOI: 10.1007/978-981-13-0854-3_12] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Cyanobacteria are attractive hosts for converting carbon dioxide and sunlight into desirable chemical products. To engineer these organisms and manipulate their metabolic pathways, the biotechnology community has developed genetic tools to control gene expression. Many native cyanobacterial promoters and related sequence elements have been used to regulate genes of interest, and heterologous tools that use non-native small molecules to induce gene expression have been demonstrated. Overall, IPTG-based induction systems seem to be leaky and initially demonstrate small dynamic ranges in cyanobacteria. Consequently, a variety of other induction systems have been optimized to enable tighter control of gene expression. Tools require significant optimization because they function quite differently in cyanobacteria when compared to analogous use in model heterotrophs. We hypothesize that these differences are due to fundamental differences in physiology between organisms. This review is not intended to summarize all known products made in cyanobacteria nor the performance (titer, rate, yield) of individual strains, but instead will focus on the genetic tools and the inherent aspects of cellular physiology that influence gene expression in cyanobacteria.
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Affiliation(s)
- Gina C Gordon
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI, USA
- Microbiology Doctoral Training Program, University of Wisconsin-Madison, Madison, WI, USA
| | - Brian F Pfleger
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI, USA.
- Microbiology Doctoral Training Program, University of Wisconsin-Madison, Madison, WI, USA.
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11
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Behler J, Vijay D, Hess WR, Akhtar MK. CRISPR-Based Technologies for Metabolic Engineering in Cyanobacteria. Trends Biotechnol 2018; 36:996-1010. [DOI: 10.1016/j.tibtech.2018.05.011] [Citation(s) in RCA: 85] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Revised: 05/24/2018] [Accepted: 05/29/2018] [Indexed: 12/16/2022]
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12
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Synthetic Gene Regulation in Cyanobacteria. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1080:317-355. [DOI: 10.1007/978-981-13-0854-3_13] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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13
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Stensjö K, Vavitsas K, Tyystjärvi T. Harnessing transcription for bioproduction in cyanobacteria. PHYSIOLOGIA PLANTARUM 2018; 162:148-155. [PMID: 28762505 DOI: 10.1111/ppl.12606] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Revised: 07/04/2017] [Accepted: 07/10/2017] [Indexed: 06/07/2023]
Abstract
Sustainable production of biofuels and other valuable compounds is one of our future challenges. One tempting possibility is to use photosynthetic cyanobacteria as production factories. Currently, tools for genetic engineering of cyanobacteria are not good enough to exploit the full potential of cyanobacteria. A wide variety of expression systems will be required to adjust both the expression of heterologous enzyme(s) and metabolic routes to the best possible balance, allowing the optimal production of a particular substance. In bacteria, transcription, especially the initiation of transcription, has a central role in adjusting gene expression and thus also metabolic fluxes of cells according to environmental cues. Here we summarize the recent progress in developing tools for efficient cyanofactories, focusing especially on transcriptional regulation.
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Affiliation(s)
- Karin Stensjö
- Department of Chemistry-Ångström Laboratory, Uppsala University, Box 523, 75120 Uppsala, Sweden
| | - Konstantinos Vavitsas
- Copenhagen Plant Science Centre, Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg C, Denmark
| | - Taina Tyystjärvi
- Molecular Plant Biology, Department of Biochemistry, University of Turku, FI-20014 Turku, Finland
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Higo A, Isu A, Fukaya Y, Ehira S, Hisabori T. Application of CRISPR Interference for Metabolic Engineering of the Heterocyst-Forming Multicellular Cyanobacterium Anabaena sp. PCC 7120. PLANT & CELL PHYSIOLOGY 2018; 59:119-127. [PMID: 29112727 DOI: 10.1093/pcp/pcx166] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Accepted: 10/27/2017] [Indexed: 06/07/2023]
Abstract
Anabaena sp. PCC 7120 (A. 7120) is a heterocyst-forming multicellular cyanobacterium that performs nitrogen fixation. This cyanobacterium has been extensively studied as a model for multicellularity in prokaryotic cells. We have been interested in photosynthetic production of nitrogenous compounds using A. 7120. However, the lack of efficient gene repression tools has limited its usefulness. We originally developed an artificial endogenous gene repression method in this cyanobacterium using small antisense RNA. However, the narrow dynamic range of repression of this method needs to be improved. Recently, clustered regularly interspaced short palindromic repeat (CRISPR) interference (CRISPRi) technology was developed and was successfully applied in some unicellular cyanobacteria. The technology requires expression of nuclease-deficient CRISPR-associated protein 9 (dCas9) and a single guide RNA (sgRNA) that is complementary to a target sequence, to repress expression of the target gene. In this study, we employed CRISPRi technology for photosynthetic production of ammonium through repression of glnA, the only gene encoding glutamine synthetase that is essential for nitrogen assimilation in A. 7120. By strictly regulating dCas9 expression using the TetR gene induction system, we succeeded in fine-tuning the GlnA protein in addition to the level of glnA transcripts. Expression of sgRNA by the heterocyst-specific nifB promoter led to efficient repression of GlnA in heterocysts, as well as in vegetative cells. Finally, we showed that ammonium is excreted into the medium only when inducers of expression of dCas9 were added. In conclusion, CRISPRi enables temporal control of desired products and will be a useful tool for basic science.
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Affiliation(s)
- Akiyoshi Higo
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, Nagatsuta 4259-R1-8, Midori-ku, Yokohama, 226-8503, Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), 4-1-8 Honcho Kawaguchi, Saitama 332-0012, Japan
- Department of Biological Sciences, Graduate School of Science and Engineering, Tokyo Metropolitan University, 1-1 Minami-Ohsawa, Hachioji, Tokyo, 192-0397 Japan
| | - Atsuko Isu
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, Nagatsuta 4259-R1-8, Midori-ku, Yokohama, 226-8503, Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), 4-1-8 Honcho Kawaguchi, Saitama 332-0012, Japan
| | - Yuki Fukaya
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, Nagatsuta 4259-R1-8, Midori-ku, Yokohama, 226-8503, Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), 4-1-8 Honcho Kawaguchi, Saitama 332-0012, Japan
| | - Shigeki Ehira
- Department of Biological Sciences, Graduate School of Science and Engineering, Tokyo Metropolitan University, 1-1 Minami-Ohsawa, Hachioji, Tokyo, 192-0397 Japan
| | - Toru Hisabori
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, Nagatsuta 4259-R1-8, Midori-ku, Yokohama, 226-8503, Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), 4-1-8 Honcho Kawaguchi, Saitama 332-0012, Japan
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Higo A, Isu A, Fukaya Y, Hisabori T. Spatio-Temporal Gene Induction Systems in the Heterocyst-Forming Multicellular Cyanobacterium Anabaena sp. PCC 7120. PLANT & CELL PHYSIOLOGY 2018; 59:82-89. [PMID: 29088489 DOI: 10.1093/pcp/pcx163] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Accepted: 10/22/2017] [Indexed: 06/07/2023]
Abstract
In the last decade, much progress has been made in the photosynthetic production of valuable products using unicellular cyanobacteria. However, production of some products requires dark, anaerobic incubation, which prevents practical applications using these organisms. Anabaena sp. PCC 7120 (A. 7120) is a heterocyst-forming multicellular cyanobacterium that is easy to manipulate genetically. Upon nitrogen step-down, this strain differentiates heterocysts that retain micro-oxic conditions for nitrogen fixation. We have developed gene regulation tools in this cyanobacterium. However, lack of a cell type-specific gene induction system has prevented A. 7120 from becoming a bona fide attractive host for photosynthetic production. We validated the usability of two transcriptional ON riboswitches that respond to theophylline or adenine. We then created a cell type-specific gene induction system by combining the riboswitches and promoters specific to either heterocysts or vegetative cells. We also created another cell type-specific gene induction system using small RNA that activates translation. Consequently, our study has expanded the toolbox for gene regulation in cyanobacteria and has enabled spatio-temporal gene induction in multicellular cyanobacteria.
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Affiliation(s)
- Akiyoshi Higo
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, Nagatsuta 4259-R1-8, Midori-ku, Yokohama, 226-8503, Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), 4-1-8 Honcho Kawaguchi, Saitama 332-0012, Japan
| | - Atsuko Isu
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, Nagatsuta 4259-R1-8, Midori-ku, Yokohama, 226-8503, Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), 4-1-8 Honcho Kawaguchi, Saitama 332-0012, Japan
| | - Yuki Fukaya
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, Nagatsuta 4259-R1-8, Midori-ku, Yokohama, 226-8503, Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), 4-1-8 Honcho Kawaguchi, Saitama 332-0012, Japan
| | - Toru Hisabori
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, Nagatsuta 4259-R1-8, Midori-ku, Yokohama, 226-8503, Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), 4-1-8 Honcho Kawaguchi, Saitama 332-0012, Japan
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16
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Mikami Y, Yoneda H, Tatsukami Y, Aoki W, Ueda M. Ammonia production from amino acid-based biomass-like sources by engineered Escherichia coli. AMB Express 2017; 7:83. [PMID: 28429328 PMCID: PMC5399010 DOI: 10.1186/s13568-017-0385-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Accepted: 04/07/2017] [Indexed: 11/10/2022] Open
Abstract
The demand for ammonia is expected to increase in the future because of its importance in agriculture, industry, and hydrogen transportation. Although the Haber–Bosch process is known as an effective way to produce ammonia, the process is energy-intensive. Thus, an environmentally friendly ammonia production process is desired. In this study, we aimed to produce ammonia from amino acids and amino acid-based biomass-like resources by modifying the metabolism of Escherichia coli. By engineering metabolic flux to promote ammonia production using the overexpression of the ketoisovalerate decarboxylase gene (kivd), derived from Lactococcus lactis, ammonia production from amino acids was 351 mg/L (36.6% yield). Furthermore, we deleted the glnA gene, responsible for ammonia assimilation. Using yeast extract as the sole source of carbon and nitrogen, the resultant strain produced 458 mg/L of ammonia (47.8% yield) from an amino acid-based biomass-like material. The ammonia production yields obtained are the highest reported to date. This study suggests that it will be possible to produce ammonia from waste biomass in an environmentally friendly process.
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Spatial separation of photosynthesis and ethanol production by cell type-specific metabolic engineering of filamentous cyanobacteria. Appl Microbiol Biotechnol 2017; 102:1523-1531. [DOI: 10.1007/s00253-017-8620-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Revised: 10/24/2017] [Accepted: 10/30/2017] [Indexed: 12/22/2022]
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Higo A, Isu A, Fukaya Y, Hisabori T. Designing Synthetic Flexible Gene Regulation Networks Using RNA Devices in Cyanobacteria. ACS Synth Biol 2017; 6:55-61. [PMID: 27636301 DOI: 10.1021/acssynbio.6b00201] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
In recent years, studies on the development of gene regulation tools in cyanobacteria have been extensively conducted toward efficient production of valuable chemicals. However, there is considerable scope for improving the economic feasibility of production. To improve a recently reported gene induction system using anhydrotetracycline (aTc)-TetR and an endogenous gene repression system using small antisense RNA in the filamentous nitrogen-fixing cyanobacterium Anabaena sp. PCC 7120 (Anabaena), we constructed a positive feedback loop, in which gfp and a small antisense RNA for tetR are controlled by an aTc-inducible promoter. GFP expression in this improved system was higher and longer than the system lacking tetR repression. In addition, by using TetR aptamer and a riboswitch, we succeeded in achieving a superior and longer induction of GFP expression even under high-light conditions. Hence, efficient gene induction systems were established in Anabaena by designing a gene regulation network using RNA-based tools.
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Affiliation(s)
- Akiyoshi Higo
- Laboratory
for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, Nagatsuta 4259-R1-8, Midori-ku, Yokohama 226-8503, Japan
- Core
Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Tokyo 102-0075, Japan
| | - Atsuko Isu
- Laboratory
for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, Nagatsuta 4259-R1-8, Midori-ku, Yokohama 226-8503, Japan
- Core
Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Tokyo 102-0075, Japan
| | - Yuki Fukaya
- Laboratory
for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, Nagatsuta 4259-R1-8, Midori-ku, Yokohama 226-8503, Japan
- Core
Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Tokyo 102-0075, Japan
| | - Toru Hisabori
- Laboratory
for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, Nagatsuta 4259-R1-8, Midori-ku, Yokohama 226-8503, Japan
- Core
Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Tokyo 102-0075, Japan
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19
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Mihara S, Yoshida K, Higo A, Hisabori T. Functional Significance of NADPH-Thioredoxin Reductase C in the Antioxidant Defense System of Cyanobacterium Anabaena sp. PCC 7120. PLANT & CELL PHYSIOLOGY 2017; 58:86-94. [PMID: 28011872 DOI: 10.1093/pcp/pcw182] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2016] [Accepted: 10/18/2016] [Indexed: 06/06/2023]
Abstract
The redox regulation system is widely accepted as a crucial mechanism for controlling the activities of various metabolic enzymes. In addition to thioredoxin reductase/thioredoxin cascades, NADPH-thioredoxin reductase C (NTRC), a hybrid protein formed by an NADPH-thioredoxin reductase domain and a thioredoxin (Trx) domain, is present in chloroplasts and in most cyanobacteria species. Although several target proteins and physiological functions of NTRC in chloroplasts have been characterized, little is known about NTRC functions in cyanobacteria. Therefore, we investigated the molecular basis and physiological significance of NTRC-dependent redox regulation in the filamentous heterocyst-forming nitrogen-fixing cyanobacterium Anabaena sp. PCC 7120 (Anabaena 7120). Initially, we identified six candidate NTRC targets in Anabaena 7120 using NTRC affinity chromatography. Subsequently, we compared the efficiency of reducing-equivalent transfer from NTRC and Trx-m1 to the NTRC target protein 2-Cys peroxiredoxin. Biochemical analyses revealed that compared with Trx-m1, NTRC more efficiently transfers reducing equivalents to 2-Cys peroxiredoxin. Subsequently, we constructed and analyzed an ntrC knockout strain in Anabaena 7120. The mutant showed impaired growth under oxidative stress conditions and lower concentrations of reduced 2-Cys peroxiredoxin in cells. Taken together, the present in vitro and in vivo results indicate that NTRC is a significant electron donor for 2-Cys peroxiredoxin and plays a pivotal role in antioxidant defense systems in Anabaena 7120 cells.
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Affiliation(s)
- Shoko Mihara
- Laboratory for Chemistry and Life Science, Tokyo Institute of Technology, Nagatsuta, Midori-ku, Yokohama, Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Tokyo, Japan
| | - Keisuke Yoshida
- Laboratory for Chemistry and Life Science, Tokyo Institute of Technology, Nagatsuta, Midori-ku, Yokohama, Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Tokyo, Japan
| | - Akiyoshi Higo
- Laboratory for Chemistry and Life Science, Tokyo Institute of Technology, Nagatsuta, Midori-ku, Yokohama, Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Tokyo, Japan
| | - Toru Hisabori
- Laboratory for Chemistry and Life Science, Tokyo Institute of Technology, Nagatsuta, Midori-ku, Yokohama, Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Tokyo, Japan
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