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Grivalský T, Lakatos GE, Štěrbová K, Manoel JAC, Beloša R, Divoká P, Kopp J, Kriechbaum R, Spadiut O, Zwirzitz A, Trenzinger K, Masojídek J. Poly-β-hydroxybutyrate production by Synechocystis MT_a24 in a raceway pond using urban wastewater. Appl Microbiol Biotechnol 2024; 108:44. [PMID: 38180554 DOI: 10.1007/s00253-023-12924-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Revised: 10/16/2023] [Accepted: 10/24/2023] [Indexed: 01/06/2024]
Abstract
Poly-β-hydroxybutyrate (PHB) is a potential source of biodegradable plastics that are environmentally friendly due to their complete degradation to water and carbon dioxide. This study aimed to investigate PHB production in the cyanobacterium Synechocystis sp. PCC6714 MT_a24 in an outdoor bioreactor using urban wastewater as a sole nutrient source. The culture was grown in a thin-layer raceway pond with a working volume of 100 L, reaching a biomass density of up to 3.5 g L-1 of cell dry weight (CDW). The maximum PHB content was found under nutrient-limiting conditions in the late stationary phase, reaching 23.7 ± 2.2% PHB per CDW. These data are one of the highest reported for photosynthetic production of PHB by cyanobacteria, moreover using urban wastewater in pilot-scale cultivation which multiplies the potential of sustainable cultivation approaches. Contamination by grazers (Poterioochromonas malhamensis) was managed by culturing Synechocystis in a highly alkaline environment (pH about 10.5) which did not significantly affect the culture growth. Furthermore, the strain MT_a24 showed significant wastewater nutrient remediation removing about 72% of nitrogen and 67% of phosphorus. These trials demonstrate that the photosynthetic production of PHB by Synechocystis sp. PCC6714 MT_a24 in the outdoor thin-layer bioreactor using urban wastewater and ambient carbon dioxide. It shows a promising approach for the cost-effective and sustainable production of biodegradable carbon-negative plastics. KEY POINTS: • High PHB production by cyanobacteria in outdoor raceway pond • Urban wastewater used as a sole source of nutrients for phototrophic growth • Potential for cost-effective and sustainable production of biodegradable plastics.
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Affiliation(s)
- Tomáš Grivalský
- Institute of Microbiology of the Czech Academy of Sciences, Centre Algatech, Laboratory of Algal Biotechnology, Novohradská 237, Třeboň, Czech Republic.
| | - Gergely Ernő Lakatos
- Institute of Microbiology of the Czech Academy of Sciences, Centre Algatech, Laboratory of Algal Biotechnology, Novohradská 237, Třeboň, Czech Republic
| | - Karolína Štěrbová
- Institute of Microbiology of the Czech Academy of Sciences, Centre Algatech, Laboratory of Algal Biotechnology, Novohradská 237, Třeboň, Czech Republic
| | - João Artur Câmara Manoel
- Institute of Microbiology of the Czech Academy of Sciences, Centre Algatech, Laboratory of Algal Biotechnology, Novohradská 237, Třeboň, Czech Republic
- Faculty of Science, University of South Bohemia, Branišovská 1645/31a, České Budějovice, Czech Republic
| | - Romana Beloša
- Institute of Microbiology of the Czech Academy of Sciences, Centre Algatech, Laboratory of Algal Biotechnology, Novohradská 237, Třeboň, Czech Republic
| | - Petra Divoká
- Institute of Microbiology of the Czech Academy of Sciences, Centre Algatech, Laboratory of Algal Biotechnology, Novohradská 237, Třeboň, Czech Republic
| | - Julian Kopp
- Technische Universität Wien, Institute of Chemical, Environmental and Bioscience Engineering, Research Division Biochemical Engineering, Getreidemarkt 9, Vienna, Austria
| | - Ricarda Kriechbaum
- Technische Universität Wien, Institute of Chemical, Environmental and Bioscience Engineering, Research Division Biochemical Engineering, Getreidemarkt 9, Vienna, Austria
| | - Oliver Spadiut
- Technische Universität Wien, Institute of Chemical, Environmental and Bioscience Engineering, Research Division Biochemical Engineering, Getreidemarkt 9, Vienna, Austria
| | - Alexander Zwirzitz
- Biosciences Research Group, University of Applied Sciences, Stelzhamerstraße 23, Wels, Austria
| | - Kevin Trenzinger
- Biosciences Research Group, University of Applied Sciences, Stelzhamerstraße 23, Wels, Austria
| | - Jiří Masojídek
- Institute of Microbiology of the Czech Academy of Sciences, Centre Algatech, Laboratory of Algal Biotechnology, Novohradská 237, Třeboň, Czech Republic
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Wang J, Huang J, Liu S. The production, recovery, and valorization of polyhydroxybutyrate (PHB) based on circular bioeconomy. Biotechnol Adv 2024; 72:108340. [PMID: 38537879 DOI: 10.1016/j.biotechadv.2024.108340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Revised: 02/07/2024] [Accepted: 03/01/2024] [Indexed: 04/17/2024]
Abstract
As an energy-storage substance of microorganisms, polyhydroxybutyrate (PHB) is a promising alternative to petrochemical polymers. Under appropriate fermentation conditions, PHB-producing strains with metabolic diversity can efficiently synthesize PHB using various carbon sources. Carbon-rich wastes may serve as alternatives to pure sugar substrates to reduce the cost of PHB production. Genetic engineering strategies can further improve the efficiency of substrate assimilation and PHB synthesis. In the downstream link, PHB recycling strategies based on green chemistry concepts can replace PHB extraction using chlorinated solvents to enhance the economics of PHB production and reduce the potential risks of environmental pollution and health damage. To avoid carbon loss caused by biodegradation in the traditional sense, various strategies have been developed to degrade PHB waste into monomers. These monomers can serve as platform chemicals to synthesize other functional compounds or as substrates for PHB reproduction. The sustainable potential and cycling value of PHB are thus reflected. This review summarized the recent progress of strains, substrates, and fermentation approaches for microbial PHB production. Analyses of available strategies for sustainable PHB recycling were also included. Furthermore, it discussed feasible pathways for PHB waste valorization. These contents may provide insights for constructing PHB-based comprehensive biorefinery systems.
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Affiliation(s)
- Jianfei Wang
- Department of Chemical Engineering, SUNY College of Environmental Science and Forestry, Syracuse, NY 13210, United States
| | - Jiaqi Huang
- Department of Chemical Engineering, SUNY College of Environmental Science and Forestry, Syracuse, NY 13210, United States
| | - Shijie Liu
- Department of Chemical Engineering, SUNY College of Environmental Science and Forestry, Syracuse, NY 13210, United States.
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Altamira-Algarra B, Rueda E, Lage A, San León D, Martínez-Blanch JF, Nogales J, García J, Gonzalez-Flo E. New strategy for bioplastic and exopolysaccharides production: Enrichment of field microbiomes with cyanobacteria. N Biotechnol 2023; 78:141-149. [PMID: 37852438 DOI: 10.1016/j.nbt.2023.10.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Revised: 09/29/2023] [Accepted: 10/14/2023] [Indexed: 10/20/2023]
Abstract
Seven photosynthethic microbiomes were collected from field environmental samples to test their potential in polyhydroxybutyrate (PHB) and exopolysaccharides (EPS) production, both alternatives to chemical-based polymers. Microscope observations together with microbial sequence analysis revealed the microbiome enrichment in cyanobacteria after culture growth under phosphorus limitation. PHB and EPS production were studied under three culture factors (phototrophy, mixotrophy and heterotrophy) by evaluating and optimizing the effect of three parameters (organic and inorganic carbon and days under light:dark cycles) by Box-Behnken design. Results showed that optimal conditions for both biopolymers synthesis were microbiome-dependent; however, the addition of organic carbon boosted PHB production in all the tested microbiomes, producing up to 14 %dcw PHB with the addition of 1.2 g acetate·L-1 and seven days under light:dark photoperiods. The highest EPS production was 59 mg·L-1 with the addition of 1.2 g acetate·L-1 and four days under light:dark photoperiods. The methodology used is suitable for enriching microbiomes in cyanobacteria, and for testing the best conditions for bioproduct synthesis for further scale up.
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Affiliation(s)
- Beatriz Altamira-Algarra
- GEMMA-Group of Environmental Engineering and Microbiology, Department of Civil and Environmental Engineering, Escola d'Enginyeria de Barcelona Est (EEBE), Universitat Politècnica de Catalunya-BarcelonaTech, Av. Eduard Maristany 16, Building C5.1, E-08019 Barcelona, Spain
| | - Estel Rueda
- GEMMA-Group of Environmental Engineering and Microbiology, Department of Civil and Environmental Engineering, Escola d'Enginyeria de Barcelona Est (EEBE), Universitat Politècnica de Catalunya-BarcelonaTech, Av. Eduard Maristany 16, Building C5.1, E-08019 Barcelona, Spain
| | - Artai Lage
- GEMMA-Group of Environmental Engineering and Microbiology, Department of Civil and Environmental Engineering, Escola d'Enginyeria de Barcelona Est (EEBE), Universitat Politècnica de Catalunya-BarcelonaTech, Av. Eduard Maristany 16, Building C5.1, E-08019 Barcelona, Spain
| | - David San León
- Department of Systems Biology, Centro Nacional de Biotecnología, CSIC, Madrid, Spain; Interdisciplinary Platform for Sustainable Plastics towards a Circular Economy-Spanish National Research Council (SusPlast-CSIC), Madrid, Spain
| | - Juan F Martínez-Blanch
- Department of preventive medicine, public health, food sciences, toxicology and forensic medicine, Universitat de Valencia, Valencia, Spain; Biopolis S.L., ADM, Parc Cientifc Universidad De Valencia, Edif. 2, C/ Catedrático Agustín Escardino Benlloch, 9, 46980 Paterna, Spain
| | - Juan Nogales
- Department of Systems Biology, Centro Nacional de Biotecnología, CSIC, Madrid, Spain; Interdisciplinary Platform for Sustainable Plastics towards a Circular Economy-Spanish National Research Council (SusPlast-CSIC), Madrid, Spain
| | - Joan García
- GEMMA-Group of Environmental Engineering and Microbiology, Department of Civil and Environmental Engineering, Universitat Politècnica de Catalunya-BarcelonaTech, c/ Jordi Girona 1-3, Building D1, E-08034 Barcelona, Spain
| | - Eva Gonzalez-Flo
- GEMMA-Group of Environmental Engineering and Microbiology, Department of Civil and Environmental Engineering, Escola d'Enginyeria de Barcelona Est (EEBE), Universitat Politècnica de Catalunya-BarcelonaTech, Av. Eduard Maristany 16, Building C5.1, E-08019 Barcelona, Spain.
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Tharasirivat V, Jantaro S. Increased Biomass and Polyhydroxybutyrate Production by Synechocystis sp. PCC 6803 Overexpressing RuBisCO Genes. Int J Mol Sci 2023; 24:ijms24076415. [PMID: 37047389 PMCID: PMC10094337 DOI: 10.3390/ijms24076415] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2023] [Revised: 03/20/2023] [Accepted: 03/26/2023] [Indexed: 03/31/2023] Open
Abstract
The overexpression of the RuBisCO (rbc) gene has recently become an achievable strategy for increasing cyanobacterial biomass and overcoming the biocompound production restriction. We successfully constructed two rbc-overexpressing Synechocystis sp. PCC 6803 strains (OX), including a strain overexpressing a large subunit of RuBisCO (OXrbcL) and another strain overexpressing all large, chaperone, and small subunits of RuBisCO (OXrbcLXS), resulting in higher and faster growth than wild type under sodium bicarbonate supplementation. This increased biomass of OX strains significantly contributed to the higher polyhydroxybutyrate (PHB) production induced by nutrient-deprived conditions, in particular nitrogen (N) and phosphorus (P). As a result of higher PHB contents in OX strains occurring at days 7 and 9 of nutrient deprivation, this enhancement was apparently made possible by cells preferentially maintaining their internal lipids while accumulating less glycogen. The OXrbcLXS strain, with the highest level of PHB at about 39 %w/dry cell weight (DCW) during 7 days of BG11-NP treatment, contained a lower glycogen level (31.9 %w/DCW) than wild type control (40 %w/DCW). In contrast, the wild type control strain exposed to N- and NP-stresses tended to retain lipid levels and store more glycogen than PHB. In this model, we, for the first time, implemented a RuBisCO-overexpressing cyanobacterial factory for overproducing PHB, destined for biofuel and biomaterial biotechnology.
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Dabravolski SA, Isayenkov SV. Metabolites Facilitating Adaptation of Desert Cyanobacteria to Extremely Arid Environments. Plants (Basel) 2022; 11:3225. [PMID: 36501264 PMCID: PMC9736550 DOI: 10.3390/plants11233225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/22/2022] [Revised: 11/17/2022] [Accepted: 11/22/2022] [Indexed: 06/17/2023]
Abstract
Desert is one of the harshest environments on the planet, characterized by exposure to daily fluctuations of extreme conditions (such as high temperature, low nitrogen, low water, high salt, etc.). However, some cyanobacteria are able to live and flourish in such conditions, form communities, and facilitate survival of other organisms. Therefore, to ensure survival, desert cyanobacteria must develop sophisticated and comprehensive adaptation strategies to enhance their tolerance to multiple simultaneous stresses. In this review, we discuss the metabolic pathways used by desert cyanobacteria to adapt to extreme arid conditions. In particular, we focus on the extracellular polysaccharides and compatible solutes biosynthesis pathways and their evolution and special features. We also discuss the role of desert cyanobacteria in the improvement of soil properties and their ecological and environmental impact on soil communities. Finally, we summarize recent achievements in the application of desert cyanobacteria to prevent soil erosion and desertification.
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Affiliation(s)
- Siarhei A. Dabravolski
- Department of Biotechnology Engineering, Braude Academic College of Engineering, Snunit 51, Karmiel 2161002, Israel
| | - Stanislav V. Isayenkov
- Department of Plant Food Products and Biofortification, Institute of Food Biotechnology and Genomics, The National Academy of Sciences of Ukraine, Osipovskogo Str. 2a, 04123 Kyiv, Ukraine
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Eungrasamee K, Lindblad P, Jantaro S. Enhanced productivity of extracellular free fatty acids by gene disruptions of acyl-ACP synthetase and S-layer protein in Synechocystis sp. PCC 6803. Biotechnol Biofuels 2022; 15:99. [PMID: 36153604 PMCID: PMC9509626 DOI: 10.1186/s13068-022-02197-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Accepted: 09/01/2022] [Indexed: 11/17/2022]
Abstract
Background Based on known metabolic response to excess free fatty acid (FFA) products, cyanobacterium Synechocystis sp. PCC 6803 preferentially both recycles via FFA recycling process and secrets them into medium. Engineered cyanobacteria with well growth and highly secreted FFA capability are considered best resources for biofuel production and sustainable biotechnology. In this study, to achieve the higher FFA secretion goal, we successfully constructs Synechocystis sp. PCC 6803 mutants disrupting genes related to FFA recycling reaction (aas gene encoding acyl–acyl carrier protein synthetase), and surface layer protein (encoded by sll1951). Results Three Synechocystis sp. PCC 6803 engineered strains, including two single mutants lacking aas (KA) and sll1951 (KS), and one double mutant lacking both aas and sll1951 (KAS), significantly secreted FFAs higher than that of wild type (WT). Certain increase of secreted FFAs was noted when cells were exposed to nitrogen-deficient conditions, BG11-half N and BG11-N conditions, with the exception of strain KS. Under BG11-N condition at day 10, strain KAS strikingly secreted FFAs products up to 40%w/DCW or 238.1 mg/L, with trace amounts of PHB. Unexpectedly, strain KS, with S-layer disruption, appeared to have endured longer in BG11-N growth medium. This strain KS significantly acclimated to the BG11-N environment by accumulating a greater glycogen pool with lower FFA production, whereas strain KA favored higher PHB and intracellular lipid accumulations with moderate FFA secretion. Conclusions Mutations of both aas and sll1951 genes in Synechocystis sp. PCC 6803 significantly improved the productivity of secreted FFAs, especially under nitrogen deprivation.
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Koch M, Noonan AJC, Qiu Y, Dofher K, Kieft B, Mottahedeh S, Shastri M, Hallam SJ. The survivor strain: isolation and characterization of Phormidium yuhuli AB48, a filamentous phototactic cyanobacterium with biotechnological potential. Front Bioeng Biotechnol 2022; 10:932695. [PMID: 36046667 PMCID: PMC9420970 DOI: 10.3389/fbioe.2022.932695] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2022] [Accepted: 06/27/2022] [Indexed: 11/13/2022] Open
Abstract
Despite their recognized potential, current applications of cyanobacteria as microbial cell factories remain in early stages of development. This is partly due to the fact that engineered strains are often difficult to grow at scale. This technical challenge contrasts with the dense and highly productive cyanobacteria populations thriving in many natural environments. It has been proposed that the selection of strains pre-adapted for growth in industrial photobioreactors could enable more productive cultivation outcomes. Here, we described the initial morphological, physiological, and genomic characterization of Phormidium yuhuli AB48 isolated from an industrial photobioreactor environment. P. yuhuli AB48 is a filamentous phototactic cyanobacterium with a growth rate comparable to Synechocystis sp. PCC 6803. The isolate forms dense biofilms under high salinity and alkaline conditions and manifests a similar nutrient profile to Arthrospira platensis (Spirulina). We sequenced, assembled, and analyzed the P. yuhuli AB48 genome, the first closed circular isolate reference genome for a member of the Phormidium genus. We then used cultivation experiments in combination with proteomics and metabolomics to investigate growth characteristics and phenotypes related to industrial scale cultivation, including nitrogen and carbon utilization, salinity, and pH acclimation, as well as antibiotic resistance. These analyses provide insight into the biological mechanisms behind the desirable growth properties manifested by P. yuhuli AB48 and position it as a promising microbial cell factory for industrial-scale bioproduction[221, 1631].
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Affiliation(s)
- Moritz Koch
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, BC, Canada
| | - Avery J. C. Noonan
- Genome Science and Technology Program, University of British Columbia, Vancouver, BC, Canada
- ECOSCOPE Training Program, University of British Columbia, Vancouver, BC, Canada
| | - Yilin Qiu
- Genome Science and Technology Program, University of British Columbia, Vancouver, BC, Canada
| | - Kalen Dofher
- Genome Science and Technology Program, University of British Columbia, Vancouver, BC, Canada
| | - Brandon Kieft
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, BC, Canada
| | | | | | - Steven J. Hallam
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, BC, Canada
- Genome Science and Technology Program, University of British Columbia, Vancouver, BC, Canada
- ECOSCOPE Training Program, University of British Columbia, Vancouver, BC, Canada
- Graduate Program in Bioinformatics, University of British Columbia, Vancouver, BC, Canada
- Life Sciences Institute, University of British Columbia, Vancouver, BC, Canada
- *Correspondence: Steven J. Hallam,
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Rueda E, Álvarez-González A, Vila J, Díez-Montero R, Grifoll M, García J. Inorganic carbon stimulates the metabolic routes related to the polyhdroxybutyrate production in a Synechocystis sp. strain (cyanobacteria) isolated from wastewater. Sci Total Environ 2022; 829:154691. [PMID: 35318053 DOI: 10.1016/j.scitotenv.2022.154691] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 03/11/2022] [Accepted: 03/16/2022] [Indexed: 06/14/2023]
Abstract
Cyanobacteria are capable of transforming CO2 into polyhydroxybutyrate (PHB). In this study, different inorganic carbon concentrations (0-2 gC L-1) were evaluated for a Synechocystis sp. strain isolated from wastewater. Quantitative RT-qPCR was also performed to decipher the links between inorganic carbon and PHB and glycogen metabolism. 2 gC L-1 of bicarbonate stimulated cell growth, nutrients consumption and production of PHB. Using this concentration, a 14%dcw of PHB and an average productivity of 2.45 mgPHB L-1 d-1 were obtained. Gene expression analysis revelated that these conditions caused the overexpression of genes related to glycogen and PHB synthesis. Moreover, a positive correlation between the genes codifying for the glycogen phosphorylase, the acetyl-CoA reductase and the poly(3-hydroxyalkanoate) polymerase was found, meaning that PHB synthesis and glycogen catabolism are strongly related. These results provide an exhaustive evaluation of the effect of carbon on the PHB production and cyanobacterial metabolism.
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Affiliation(s)
- Estel Rueda
- GEMMA-Group of Environmental Engineering and Microbiology, Department of Civil and Environmental Engineering, Escola d'Enginyeria de Barcelona Est (EEBE), Universitat Politècnica de Catalunya-BarcelonaTech, Av. Eduard Maristany 16, Building C5.1, E-08019 Barcelona, Spain
| | - Ana Álvarez-González
- GEMMA-Group of Environmental Engineering and Microbiology, Department of Civil and Environmental Engineering, Universitat Politècnica de Catalunya-BarcelonaTech, c/ Jordi Girona 1-3, Building D1, E-08034 Barcelona, Spain
| | - Joaquim Vila
- Department of Genetics, Microbiology and Statistics, Faculty of Biology, University of Barcelona, Diagonal 643, Barcelona E-08028, Spain
| | - Rubén Díez-Montero
- GEMMA-Group of Environmental Engineering and Microbiology, Department of Civil and Environmental Engineering, Universitat Politècnica de Catalunya-BarcelonaTech, c/ Jordi Girona 1-3, Building D1, E-08034 Barcelona, Spain
| | - Magdalena Grifoll
- Department of Genetics, Microbiology and Statistics, Faculty of Biology, University of Barcelona, Diagonal 643, Barcelona E-08028, Spain
| | - Joan García
- GEMMA-Group of Environmental Engineering and Microbiology, Department of Civil and Environmental Engineering, Universitat Politècnica de Catalunya-BarcelonaTech, c/ Jordi Girona 1-3, Building D1, E-08034 Barcelona, Spain.
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Rueda E, Altamira-Algarra B, García J. Process optimization of the polyhydroxybutyrate production in the cyanobacteria Synechocystis sp. and Synechococcus sp. Bioresour Technol 2022; 356:127330. [PMID: 35589041 DOI: 10.1016/j.biortech.2022.127330] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Revised: 05/11/2022] [Accepted: 05/13/2022] [Indexed: 06/15/2023]
Abstract
The effect of four parameters (acetate, NaCl, inorganic carbon and days in darkness) affecting the polyhydroxybutyrate (PHB) production were tested and optimized for Synechococcus sp. and Synechocystis sp. using a Box-Behnken design. The optimal conditions for Synechocystis sp. were found to be 1.2 g L-1 of acetate, 4 gC L-1 of NaHCO3, 18 g L-1 of NaCl and 0 days in darkness. For Synechococcus sp., equal acetate concentration and days in darkness, and lower inorganic carbon and NaCl concentrations than those for Synechocystis sp. were needed (0.05 g L-1 inorganic carbon and 9 g L-1 NaCl). Optimal conditions were scaled up to 3 L photobioreactors. Using Synechocystis sp., 5.6 %dcw of PHB was obtained whether adding or not acetate. In opposition, a maximum of 26.1 %dcw by using acetate was reached with Synechococcus sp. These results provide an easy method to optimize the cultivation conditions to enhance PHB production with cyanobacteria.
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Affiliation(s)
- Estel Rueda
- GEMMA-Group of Environmental Engineering and Microbiology, Department of Civil and Environmental Engineering, Escola d'Enginyeria de Barcelona Est (EEBE), Universitat Politècnica de Catalunya-BarcelonaTech, Av. Eduard Maristany 16, Building C5.1, E-08019 Barcelona, Spain
| | - Beatriz Altamira-Algarra
- GEMMA-Group of Environmental Engineering and Microbiology, Department of Civil and Environmental Engineering, Escola d'Enginyeria de Barcelona Est (EEBE), Universitat Politècnica de Catalunya-BarcelonaTech, Av. Eduard Maristany 16, Building C5.1, E-08019 Barcelona, Spain
| | - Joan García
- GEMMA-Group of Environmental Engineering and Microbiology, Department of Civil and Environmental Engineering, Universitat Politècnica de Catalunya-BarcelonaTech, c/ Jordi Girona 1-3, Building D1, E-08034 Barcelona. Spain.
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Muth-Pawlak D, Kreula S, Gollan PJ, Huokko T, Allahverdiyeva Y, Aro EM. Patterning of the Autotrophic, Mixotrophic, and Heterotrophic Proteomes of Oxygen-Evolving Cyanobacterium Synechocystis sp. PCC 6803. Front Microbiol 2022; 13:891895. [PMID: 35694301 PMCID: PMC9175036 DOI: 10.3389/fmicb.2022.891895] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Accepted: 03/25/2022] [Indexed: 11/13/2022] Open
Abstract
Proteomes of an oxygenic photosynthetic cyanobacterium, Synechocystis sp. PCC 6803, were analyzed under photoautotrophic (low and high CO2, assigned as ATLC and ATHC), photomixotrophic (MT), and light-activated heterotrophic (LAH) conditions. Allocation of proteome mass fraction to seven sub-proteomes and differential expression of individual proteins were analyzed, paying particular attention to photosynthesis and carbon metabolism–centered sub-proteomes affected by the quality and quantity of the carbon source and light regime upon growth. A distinct common feature of the ATHC, MT, and LAH cultures was low abundance of inducible carbon-concentrating mechanisms and photorespiration-related enzymes, independent of the inorganic or organic carbon source. On the other hand, these cells accumulated a respiratory NAD(P)H dehydrogenase I (NDH-11) complex in the thylakoid membrane (TM). Additionally, in glucose-supplemented cultures, a distinct NDH-2 protein, NdbA, accumulated in the TM, while the plasma membrane-localized NdbC and terminal oxidase decreased in abundance in comparison to both AT conditions. Photosynthetic complexes were uniquely depleted under the LAH condition but accumulated under the ATHC condition. The MT proteome displayed several heterotrophic features typical of the LAH proteome, particularly including the high abundance of ribosome as well as amino acid and protein biosynthesis machinery-related components. It is also noteworthy that the two equally light-exposed ATHC and MT cultures allocated similar mass fractions of the total proteome to the seven distinct sub-proteomes. Unique trophic condition-specific expression patterns were likewise observed among individual proteins, including the accumulation of phosphate transporters and polyphosphate polymers storing energy surplus in highly energetic bonds under the MT condition and accumulation under the LAH condition of an enzyme catalyzing cyanophycin biosynthesis. It is concluded that the rigor of cell growth in the MT condition results, to a great extent, by combining photosynthetic activity with high intracellular inorganic carbon conditions created upon glucose breakdown and release of CO2, besides the direct utilization of glucose-derived carbon skeletons for growth. This combination provides the MT cultures with excellent conditions for growth that often exceeds that of mere ATHC.
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Testa RL, Delpino C, Estrada V, Diaz MS. Development of in silico strategies to photoautotrophically produce poly-β-hydroxybutyrate (PHB) by cyanobacteria. ALGAL RES 2022. [DOI: 10.1016/j.algal.2021.102621] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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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. Biotechnol 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] [What about the content of this article? (0)] [Affiliation(s)] [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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Sirohi R, Lee JS, Yu BS, Roh H, Sim SJ. Sustainable production of polyhydroxybutyrate from autotrophs using CO 2 as feedstock: Challenges and opportunities. Bioresour Technol 2021; 341:125751. [PMID: 34416655 DOI: 10.1016/j.biortech.2021.125751] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Revised: 08/05/2021] [Accepted: 08/07/2021] [Indexed: 05/05/2023]
Abstract
Due to industrialization and rapid increase in world population, the global energy consumption has increased dramatically. As a consequence, there is increased consumption of fossil fuels, leading to a rapid increase in CO2 concentration in the atmosphere. This accumulated CO2 can be efficiently used by autotrophs as a carbon source to produce chemicals and biopolymers. There has been increasing attention on the production of polyhydroxybutyrate (PHB), a biopolymer, with focus on reducing the production cost. For this, cheaper renewable feedstocks, molecular tools, including metabolic and genetic engineering have been explored to improve microbial strains along with process engineering aspects for scale-up of PHB production. This review discusses the recent advents on the utilization of CO2 as feedstock especially by engineered autotrophs, for sustainable production of PHB. The review also discusses the innovations in cultivation technology and process monitoring while understanding the underlying mechanisms for CO2 to biopolymer conversion.
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Affiliation(s)
- Ranjna Sirohi
- Department of Chemical & Biological Engineering, Korea University, Seoul 136713, Republic of Korea
| | - Jeong Seop Lee
- Department of Chemical & Biological Engineering, Korea University, Seoul 136713, Republic of Korea
| | - Byung Sun Yu
- Department of Chemical & Biological Engineering, Korea University, Seoul 136713, Republic of Korea
| | - Hyejin Roh
- Department of Chemical & Biological Engineering, Korea University, Seoul 136713, Republic of Korea
| | - Sang Jun Sim
- Department of Chemical & Biological Engineering, Korea University, Seoul 136713, Republic of Korea.
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14
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Veerabadhran M, Natesan S, MubarakAli D, Xu S, Yang F. Using different cultivation strategies and methods for the production of microalgal biomass as a raw material for the generation of bioproducts. Chemosphere 2021; 285:131436. [PMID: 34256200 DOI: 10.1016/j.chemosphere.2021.131436] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 06/25/2021] [Accepted: 07/02/2021] [Indexed: 06/13/2023]
Abstract
Microalgal biomass and its fine chemical production from microalgae have pioneered algal bioprocess technology with few limitations such as lab-to-industry. However, laboratory-scale transitions and industrial applications are hindered by a plethora of limitations comprising expensive in culturing methods. Therefore, to emphasize the profitable benefits, the algal culturing techniques appropriately employed for large-scale microalgal biomass yield necessitates intricate assessment to emphasize the profitable benefits. The present review holistically compiles the culturing strategies for improving microalgal biomass production based on appropriate factors like designing better bioreactor designs. On the other hand, synthetic biology approaches for abridging the effective industrial transition success explored recently. Prospects in synthetic biology for enhanced microalgal biomass production based on cultivation strategies and various mechanistic modes approach to enrich cost-effective and viable output are discussed. The State-of-the-art culturing techniques encompassing enhancement of photosynthetic activity, designing bioreactor design, and potential augmenting protocols for biomass yield employing indoor cultivation in both (Open and or/closed) methods are enumerated. Further, limitations hindering the microalgal bioproducts development are critically evaluated for improving culturing techniques for microalgal cell factories, subsequently escalating the cost-benefit ratio in bioproducts synthesis from microalgae. The comprehensive analysis could provide a rational and deeper detailed insight for microalgal entrepreneurs through alternative culturing technology viz., synthetic biology and genome engineering in an Industrial perspective arena.
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Affiliation(s)
- Maruthanayagam Veerabadhran
- Hunan Provincial Key Laboratory of Clinical Epidemiology, Xiangya School of Public Health, Central South University, 110 Xiangya Road, Changsha, Hunan 410078, China.
| | - Sivakumar Natesan
- Department of Molecular Microbiology, School of Biotechnology, Madurai Kamaraj University, Madurai 625021, Tamil Nadu, India.
| | - Davoodbasha MubarakAli
- School of Life Sciences, B.S. Abdur Rahman Crescent Institute of Science and Technology, Chennai, Tamil Nadu, India.
| | - Shuaishuai Xu
- Hunan Provincial Key Laboratory of Clinical Epidemiology, Xiangya School of Public Health, Central South University, 110 Xiangya Road, Changsha, Hunan 410078, China.
| | - Fei Yang
- Hunan Province Key Laboratory of Typical Environmental Pollution and Health Hazards, School of Public Health, Hengyang Medical College, University of South China, Hengyang, China.
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Doppler P, Gasser C, Kriechbaum R, Ferizi A, Spadiut O. In Situ Quantification of Polyhydroxybutyrate in Photobioreactor Cultivations of Synechocystis sp. Using an Ultrasound-Enhanced ATR-FTIR Spectroscopy Probe. Bioengineering (Basel) 2021; 8:bioengineering8090129. [PMID: 34562950 PMCID: PMC8469707 DOI: 10.3390/bioengineering8090129] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 09/10/2021] [Accepted: 09/17/2021] [Indexed: 11/16/2022] Open
Abstract
Polyhydroxybutyrate (PHB) is a very promising alternative to most petroleum-based plastics with the huge advantage of biodegradability. Biotechnological production processes utilizing cyanobacteria as sustainable source of PHB require fast in situ process analytical technology (PAT) tools for sophisticated process monitoring. Spectroscopic probes supported by ultrasound particle traps provide a powerful technology for in-line, nondestructive, and real-time process analytics in photobioreactors. This work shows the great potential of using ultrasound particle manipulation to improve spectroscopic attenuated total reflection Fourier-transformed mid-infrared (ATR-FTIR) spectra as a monitoring tool for PHB production processes in photobioreactors.
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Affiliation(s)
- Philipp Doppler
- Research Division Biochemical Engineering, Institute of Chemical, Environmental and Bioscience Engineering, TU Wien, Gumpendorfer Strasse 1a, 1060 Vienna, Austria; (P.D.); (R.K.)
| | - Christoph Gasser
- usePAT GmbH, Schönbrunner Strasse 231/2.01, 1120 Vienna, Austria; (C.G.); (A.F.)
| | - Ricarda Kriechbaum
- Research Division Biochemical Engineering, Institute of Chemical, Environmental and Bioscience Engineering, TU Wien, Gumpendorfer Strasse 1a, 1060 Vienna, Austria; (P.D.); (R.K.)
| | - Ardita Ferizi
- usePAT GmbH, Schönbrunner Strasse 231/2.01, 1120 Vienna, Austria; (C.G.); (A.F.)
| | - Oliver Spadiut
- Research Division Biochemical Engineering, Institute of Chemical, Environmental and Bioscience Engineering, TU Wien, Gumpendorfer Strasse 1a, 1060 Vienna, Austria; (P.D.); (R.K.)
- Correspondence: ; Tel.: +43-1-58801-166473
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Yadav A, Maertens L, Meese T, Van Nieuwerburgh F, Mysara M, Leys N, Cuypers A, Janssen PJ. Genetic Responses of Metabolically Active Limnospira indica Strain PCC 8005 Exposed to γ-Radiation during Its Lifecycle. Microorganisms 2021; 9:microorganisms9081626. [PMID: 34442705 PMCID: PMC8400943 DOI: 10.3390/microorganisms9081626] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Revised: 07/23/2021] [Accepted: 07/28/2021] [Indexed: 11/16/2022] Open
Abstract
Two morphotypes of the cyanobacterial Limnospira indica (formerly Arthrospira sp.) strain PCC 8005, denoted as P2 (straight trichomes) and P6 (helical trichomes), were subjected to chronic gamma radiation from spent nuclear fuel (SNF) rods at a dose rate of ca. 80 Gy·h-1 for one mass doubling period (approximately 3 days) under continuous light with photoautotrophic metabolism fully active. Samples were taken for post-irradiation growth recovery and RNA-Seq transcriptional analysis at time intervals of 15, 40, and 71.5 h corresponding to cumulative doses of ca. 1450, 3200, and 5700 Gy, respectively. Both morphotypes, which were previously reported by us to display different antioxidant capacities and differ at the genomic level in 168 SNPs, 48 indels and 4 large insertions, recovered equally well from 1450 and 3200 Gy. However, while the P2 straight type recovered from 5700 Gy by regaining normal growth within 6 days, the P6 helical type took about 13 days to recover from this dose, indicating differences in their radiation tolerance and response. To investigate these differences, P2 and P6 cells exposed to the intermediate dose of gamma radiation (3200 Gy) were analyzed for differential gene expression by RNA-Seq analysis. Prior to batch normalization, a total of 1553 genes (887 and 666 of P2 and P6, respectively, with 352 genes in common) were selected based on a two-fold change in expression and a false discovery rate FDR smaller or equal to 0.05. About 85% of these 1553 genes encoded products of yet unknown function. Of the 229 remaining genes, 171 had a defined function while 58 genes were transcribed into non-coding RNA including 21 tRNAs (all downregulated). Batch normalization resulted in 660 differentially expressed genes with 98 having a function and 32 encoding RNA. From PCC 8005-P2 and PCC 8005-P6 expression patterns, it emerges that although the cellular routes used by the two substrains to cope with ionizing radiation do overlap to a large extent, both strains displayed a distinct preference of priorities.
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Affiliation(s)
- Anu Yadav
- Interdisciplinary Biosciences, Microbiology Unit, Belgian Nuclear Research Centre (SCKCEN), 2400 Mol, Belgium; (A.Y.); (L.M.); (M.M.); (N.L.)
- Environmental Biology, Centre for Environmental Sciences, Hasselt University, 3590 Diepenbeek, Belgium;
| | - Laurens Maertens
- Interdisciplinary Biosciences, Microbiology Unit, Belgian Nuclear Research Centre (SCKCEN), 2400 Mol, Belgium; (A.Y.); (L.M.); (M.M.); (N.L.)
- Research Unit in Biology of Microorganisms (URBM), Narilis Institute, University of Namur, 5000 Namur, Belgium
| | - Tim Meese
- Laboratory of Pharmaceutical Biotechnology, Ghent University, 9000 Ghent, Belgium; (T.M.); (F.V.N.)
| | - Filip Van Nieuwerburgh
- Laboratory of Pharmaceutical Biotechnology, Ghent University, 9000 Ghent, Belgium; (T.M.); (F.V.N.)
| | - Mohamed Mysara
- Interdisciplinary Biosciences, Microbiology Unit, Belgian Nuclear Research Centre (SCKCEN), 2400 Mol, Belgium; (A.Y.); (L.M.); (M.M.); (N.L.)
| | - Natalie Leys
- Interdisciplinary Biosciences, Microbiology Unit, Belgian Nuclear Research Centre (SCKCEN), 2400 Mol, Belgium; (A.Y.); (L.M.); (M.M.); (N.L.)
| | - Ann Cuypers
- Environmental Biology, Centre for Environmental Sciences, Hasselt University, 3590 Diepenbeek, Belgium;
| | - Paul Jaak Janssen
- Interdisciplinary Biosciences, Microbiology Unit, Belgian Nuclear Research Centre (SCKCEN), 2400 Mol, Belgium; (A.Y.); (L.M.); (M.M.); (N.L.)
- Correspondence: ; Tel.: +32-14-332-129
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Orthwein T, Scholl J, Spät P, Lucius S, Koch M, Macek B, Hagemann M, Forchhammer K. The novel P II-interactor PirC identifies phosphoglycerate mutase as key control point of carbon storage metabolism in cyanobacteria. Proc Natl Acad Sci U S A 2021; 118:e2019988118. [PMID: 33526690 DOI: 10.1073/pnas.2019988118] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Nitrogen limitation imposes a major transition in the lifestyle of nondiazotrophic cyanobacteria that is controlled by a complex interplay of regulatory factors involving the pervasive signal processor PII Immediately upon nitrogen limitation, newly fixed carbon is redirected toward glycogen synthesis. How the metabolic switch for diverting fixed carbon toward the synthesis of glycogen or of cellular building blocks is operated was so far poorly understood. Here, using the nondiazotrophic cyanobacterium Synechocystis sp. PCC 6803 as model system, we identified a novel PII interactor, the product of the sll0944 gene, which we named PirC. We show that PirC binds to and inhibits the activity of 2,3-phosphoglycerate-independent phosphoglycerate mutase (PGAM), the enzyme that deviates newly fixed CO2 toward lower glycolysis. The binding of PirC to either PII or PGAM is tuned by the metabolite 2-oxoglutarate (2-OG), which accumulates upon nitrogen starvation. In these conditions, the high levels of 2-OG dissociate the PirC-PII complex to promote PirC binding to and inhibition of PGAM. Accordingly, a PirC-deficient mutant showed strongly reduced glycogen levels upon nitrogen deprivation, whereas polyhydroxybutyrate granules were overaccumulated compared to wild-type. Metabolome analysis revealed an imbalance in 3-phosphoglycerate to pyruvate levels in the pirC mutant, confirming that PirC controls the carbon flux in cyanobacteria via mutually exclusive interaction with either PII or PGAM.
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Nagarajan D, Aristya GR, Lin YJ, Chang JJ, Yen HW, Chang JS. Microbial cell factories for the production of polyhydroxyalkanoates. Essays Biochem 2021:EBC20200142. [PMID: 34132340 DOI: 10.1042/EBC20200142] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 05/14/2021] [Accepted: 05/26/2021] [Indexed: 12/20/2022]
Abstract
Pollution caused by persistent petro-plastics is the most pressing problem currently, with 8 million tons of plastic waste dumped annually in the oceans. Plastic waste management is not systematized in many countries, because it is laborious and expensive with secondary pollution hazards. Bioplastics, synthesized by microorganisms, are viable alternatives to petrochemical-based thermoplastics due to their biodegradable nature. Polyhydroxyalkanoates (PHAs) are a structurally and functionally diverse group of storage polymers synthesized by many microorganisms, including bacteria and Archaea. Some of the most important PHA accumulating bacteria include Cupriavidus necator, Burkholderia sacchari, Pseudomonas sp., Bacillus sp., recombinant Escherichia coli, and certain halophilic extremophiles. PHAs are synthesized by specialized PHA polymerases with assorted monomers derived from the cellular metabolite pool. In the natural cycle of cellular growth, PHAs are depolymerized by the native host for carbon and energy. The presence of these microbial PHA depolymerases in natural niches is responsible for the degradation of bioplastics. Polyhydroxybutyrate (PHB) is the most common PHA with desirable thermoplastic-like properties. PHAs have widespread applications in various industries including biomedicine, fine chemicals production, drug delivery, packaging, and agriculture. This review provides the updated knowledge on the metabolic pathways for PHAs synthesis in bacteria, and the major microbial hosts for PHAs production. Yeasts are presented as a potential candidate for industrial PHAs production, with their high amenability to genetic engineering and the availability of industrial-scale technology. The major bottlenecks in the commercialization of PHAs as an alternative for plastics and future perspectives are also critically discussed.
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Neumann N, Doello S, Forchhammer K. Recovery of Unicellular Cyanobacteria from Nitrogen Chlorosis: A Model for Resuscitation of Dormant Bacteria. Microb Physiol 2021; 31:78-87. [PMID: 33878759 DOI: 10.1159/000515742] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Accepted: 03/06/2021] [Indexed: 11/19/2022]
Abstract
Nitrogen starvation induces developmental transitions in cyanobacteria. Whereas complex multicellular cyanobacteria of the order Nostocales can differentiate specialized cells that perform nitrogen fixation in the presence of oxygenic photosynthesis, non-diazotrophic unicellular strains, such as Synechococcus elongatus or Synechocystis PCC 6803, undergo a transition into a dormant non-growing state. Due to loss of pigments during this acclimation, the process is termed chlorosis. Cells maintain viability in this state for prolonged periods of time, until they encounter a useable nitrogen source, which triggers a highly coordinated awakening process, termed resuscitation. The minimal set of cellular activity that maintains the viability of cells during chlorosis and ensures efficient resuscitation represents the organism's equivalent of the BIOS, the basic input/output system of a computer, that helps "booting" the operation system after switching on. This review summarizes the recent research in the resuscitation of cyanobacteria, representing a powerful model for the awakening of dormant bacteria.
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Affiliation(s)
- Niels Neumann
- Interfaculty Institute of Microbiology and Infection Medicine Tübingen, Eberhard Karls University Tübingen, Tübingen, Germany
| | - Sofia Doello
- Interfaculty Institute of Microbiology and Infection Medicine Tübingen, Eberhard Karls University Tübingen, Tübingen, Germany
| | - Karl Forchhammer
- Interfaculty Institute of Microbiology and Infection Medicine Tübingen, Eberhard Karls University Tübingen, Tübingen, Germany
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Amadu AA, Qiu S, Ge S, Addico GND, Ameka GK, Yu Z, Xia W, Abbew AW, Shao D, Champagne P, Wang S. A review of biopolymer (Poly-β-hydroxybutyrate) synthesis in microbes cultivated on wastewater. Sci Total Environ 2021; 756:143729. [PMID: 33310224 DOI: 10.1016/j.scitotenv.2020.143729] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Revised: 11/04/2020] [Accepted: 11/05/2020] [Indexed: 06/12/2023]
Abstract
The large quantities of non-degradable single use plastics, production and disposal, in addition to increasing amounts of municipal and industrial wastewaters are among the major global issues known today. Biodegradable plastics from biopolymers such as Poly-β-hydroxybutyrates (PHB) produced by microorganisms are potential substitutes for non-degradable petroleum-based plastics. This paper reviews the current status of wastewater-cultivated microbes utilized in PHB production, including the various types of wastewaters suitable for either pure or mixed culture PHB production. PHB-producing strains that have the potential for commercialization are also highlighted with proposed selection criteria for choosing the appropriate PHB microbe for optimization of processes. The biosynthetic pathways involved in producing microbial PHB are also discussed to highlight the advancements in genetic engineering techniques. Additionally, the paper outlines the factors influencing PHB production while exploring other metabolic pathways and metabolites simultaneously produced along with PHB in a bio-refinery context. Furthermore, the paper explores the effects of extraction methods on PHB yield and quality to ultimately facilitate the commercial production of biodegradable plastics. This review uniquely discusses the developments in research on microbial biopolymers, specifically PHB and also gives an overview of current commercial PHB companies making strides in cutting down plastic pollution and greenhouse gases.
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Affiliation(s)
- Ayesha Algade Amadu
- Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Xiao Ling Wei 200, Nanjing 210094, PR China
| | - Shuang Qiu
- Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Xiao Ling Wei 200, Nanjing 210094, PR China
| | - Shijian Ge
- Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Xiao Ling Wei 200, Nanjing 210094, PR China.
| | - Gloria Naa Dzama Addico
- Council for Scientific and Industrial Research (CSIR) - Water Research Institute (WRI), P.O. Box AH 38, Achimota Greater Accra, Ghana
| | - Gabriel Komla Ameka
- Department of Botany, University of Ghana, P.O. Box LG55, Legon, Accra, Ghana
| | - Ziwei Yu
- Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Xiao Ling Wei 200, Nanjing 210094, PR China
| | - Wenhao Xia
- Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Xiao Ling Wei 200, Nanjing 210094, PR China
| | - Abdul-Wahab Abbew
- Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Xiao Ling Wei 200, Nanjing 210094, PR China
| | - Dadong Shao
- Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Xiao Ling Wei 200, Nanjing 210094, PR China
| | - Pascale Champagne
- Department of Civil Engineering, Queen's University, Kingston, Ontario K7L 3N6, Canada
| | - Sufeng Wang
- School of Economics and Management, Anhui Jianzhu University, Hefei, Anhui 230601, PR China
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Selim KA, Maldener I. Cellular and Molecular Strategies in Cyanobacterial Survival-"In Memory of Prof. Dr. Wolfgang Lockau". Life (Basel) 2021; 11:132. [PMID: 33572088 DOI: 10.3390/life11020132] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Accepted: 02/04/2021] [Indexed: 12/20/2022] Open
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22
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Santos M, Pereira SB, Flores C, Príncipe C, Couto N, Karunakaran E, Cravo SM, Oliveira P, Tamagnini P. Absence of KpsM (Slr0977) Impairs the Secretion of Extracellular Polymeric Substances (EPS) and Impacts Carbon Fluxes in Synechocystis sp. PCC 6803. mSphere 2021; 6:e00003-21. [PMID: 33504656 PMCID: PMC7885315 DOI: 10.1128/msphere.00003-21] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Accepted: 01/08/2021] [Indexed: 12/02/2022] Open
Abstract
Many cyanobacteria produce extracellular polymeric substances (EPS), composed mainly of heteropolysaccharides, that play a variety of physiological roles, being crucial for cell protection, motility, and biofilm formation. However, due to their complexity, the EPS biosynthetic pathways as well as their assembly and export mechanisms are still far from being fully understood. Here, we show that the absence of a putative EPS-related protein, KpsM (Slr0977), has a pleiotropic effect on Synechocystis sp. strain PCC 6803 physiology, with a strong impact on the export of EPS and carbon fluxes. The kpsM mutant exhibits a significant reduction of released polysaccharides and a smaller decrease of capsular polysaccharides, but it accumulates more polyhydroxybutyrate (PHB) than the wild type. In addition, this strain shows a light/cell density-dependent clumping phenotype and exhibits an altered protein secretion capacity. Furthermore, the most important structural component of pili, the protein PilA, was found to have a modified glycosylation pattern in the mutant compared to the wild type. Proteomic and transcriptomic analyses revealed significant changes in the mechanisms of energy production and conversion, namely, photosynthesis, oxidative phosphorylation, and carbon metabolism, in response to the inactivation of slr0977 Overall, this work shows for the first time that cells with impaired EPS secretion undergo transcriptomic and proteomic adjustments, highlighting the importance of EPS as a major carbon sink in cyanobacteria. The accumulation of PHB in cells of the mutant, without affecting significantly its fitness/growth rate, points to its possible use as a chassis for the production of compounds of interest.IMPORTANCE Most cyanobacteria produce extracellular polymeric substances (EPS) that fulfill different biological roles depending on the strain/environmental conditions. The interest in the cyanobacterial EPS synthesis/export pathways has been increasing, not only to optimize EPS production but also to efficiently redirect carbon flux toward the production of other compounds, allowing the implementation of industrial systems based on cyanobacterial cell factories. Here, we show that a Synechocystis kpsM (slr0977) mutant secretes less EPS than the wild type, accumulating more carbon intracellularly, as polyhydroxybutyrate. Further characterization showed a light/cell density-dependent clumping phenotype, altered protein secretion, and modified glycosylation of PilA. The proteome and transcriptome of the mutant revealed significant changes, namely, in photosynthesis and carbon metabolism. Altogether, this work provides a comprehensive overview of the impact of kpsM disruption on Synechocystis physiology, highlighting the importance of EPS as a carbon sink and showing how cells adapt when their secretion is impaired, and the redirection of the carbon fluxes.
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Affiliation(s)
- Marina Santos
- i3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- IBMC-Instituto de Biologia Celular e Molecular, Universidade do Porto, Porto, Portugal
- Programa Doutoral em Biologia Molecular e Celular (MCbiology), Instituto de Ciências Biomédicas Abel Salazar (ICBAS), Universidade do Porto, Porto, Portugal
| | - Sara B Pereira
- i3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- IBMC-Instituto de Biologia Celular e Molecular, Universidade do Porto, Porto, Portugal
| | - Carlos Flores
- i3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- IBMC-Instituto de Biologia Celular e Molecular, Universidade do Porto, Porto, Portugal
| | - Catarina Príncipe
- i3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- IBMC-Instituto de Biologia Celular e Molecular, Universidade do Porto, Porto, Portugal
- Departamento de Biologia, Faculdade de Ciências, Universidade do Porto, Porto, Portugal
| | - Narciso Couto
- Department of Chemical and Biological Engineering, University of Sheffield, Sheffield, United Kingdom
| | - Esther Karunakaran
- Department of Chemical and Biological Engineering, University of Sheffield, Sheffield, United Kingdom
| | - Sara M Cravo
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), Matosinhos, Portugal
- Laboratório de Química Orgânica, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, Porto, Portugal
| | - Paulo Oliveira
- i3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- IBMC-Instituto de Biologia Celular e Molecular, Universidade do Porto, Porto, Portugal
- Departamento de Biologia, Faculdade de Ciências, Universidade do Porto, Porto, Portugal
| | - Paula Tamagnini
- i3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- IBMC-Instituto de Biologia Celular e Molecular, Universidade do Porto, Porto, Portugal
- Departamento de Biologia, Faculdade de Ciências, Universidade do Porto, Porto, Portugal
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Scheurer NM, Rajarathinam Y, Timm S, Köbler C, Kopka J, Hagemann M, Wilde A. Homologs of Circadian Clock Proteins Impact the Metabolic Switch Between Light and Dark Growth in the Cyanobacterium Synechocystis sp. PCC 6803. Front Plant Sci 2021; 12:675227. [PMID: 34239525 PMCID: PMC8258377 DOI: 10.3389/fpls.2021.675227] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Accepted: 05/26/2021] [Indexed: 05/06/2023]
Abstract
The putative circadian clock system of the facultative heterotrophic cyanobacterial strain Synechocystis sp. PCC 6803 comprises the following three Kai-based systems: a KaiABC-based potential oscillator that is linked to the SasA-RpaA two-component output pathway and two additional KaiBC systems without a cognate KaiA component. Mutants lacking the genes encoding the KaiAB1C1 components or the response regulator RpaA show reduced growth in light/dark cycles and do not show heterotrophic growth in the dark. In the present study, the effect of these mutations on central metabolism was analyzed by targeted and non-targeted metabolite profiling. The strongest metabolic changes were observed in the dark in ΔrpaA and, to a lesser extent, in the ΔkaiAB1C1 mutant. These observations included the overaccumulation of 2-phosphoglycolate, which correlated with the overaccumulation of the RbcL subunit in the mutants, and taken together, these data suggest enhanced RubisCO activity in the dark. The imbalanced carbon metabolism in the ΔrpaA mutant extended to the pyruvate family of amino acids, which showed increased accumulation in the dark. Hence, the deletion of the response regulator rpaA had a more pronounced effect on metabolism than the deletion of the kai genes. The larger impact of the rpaA mutation is in agreement with previous transcriptomic analyses and likely relates to a KaiAB1C1-independent function as a transcription factor. Collectively, our data demonstrate an important role of homologs of clock proteins in Synechocystis for balanced carbon and nitrogen metabolism during light-to-dark transitions.
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Affiliation(s)
- Nina M. Scheurer
- Institute of Biology III, University of Freiburg, Freiburg, Germany
| | - Yogeswari Rajarathinam
- Applied Metabolome Analysis, Department of Molecular Physiology, Max Planck Institute of Molecular Plant Physiology, Potsdam, Germany
| | - Stefan Timm
- Department of Plant Physiology, University of Rostock, Rostock, Germany
| | - Christin Köbler
- Institute of Biology III, University of Freiburg, Freiburg, Germany
| | - Joachim Kopka
- Applied Metabolome Analysis, Department of Molecular Physiology, Max Planck Institute of Molecular Plant Physiology, Potsdam, Germany
| | - Martin Hagemann
- Department of Plant Physiology, University of Rostock, Rostock, Germany
| | - Annegret Wilde
- Institute of Biology III, University of Freiburg, Freiburg, Germany
- *Correspondence: Annegret Wilde
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Koch M, Bruckmoser J, Scholl J, Hauf W, Rieger B, Forchhammer K. Maximizing PHB content in Synechocystis sp. PCC 6803: a new metabolic engineering strategy based on the regulator PirC. Microb Cell Fact 2020; 19:231. [PMID: 33353555 PMCID: PMC7756911 DOI: 10.1186/s12934-020-01491-1] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Accepted: 12/02/2020] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND PHB (poly-hydroxy-butyrate) represents a promising bioplastic alternative with good biodegradation properties. Furthermore, PHB can be produced in a completely carbon-neutral fashion in the natural producer cyanobacterium Synechocystis sp. PCC 6803. This strain has been used as model system in past attempts to boost the intracellular production of PHB above ~ 15% per cell-dry-weight (CDW). RESULTS We have created a new strain that lacks the regulatory protein PirC (product of sll0944), which exhibits a higher activity of the phosphoglycerate mutase resulting in increased PHB pools under nutrient limiting conditions. To further improve the intracellular PHB content, two genes involved in PHB metabolism, phaA and phaB, from the known producer strain Cupriavidus necator, were introduced under the control of the strong promotor PpsbA2. The resulting strain, termed PPT1 (ΔpirC-REphaAB), produced high amounts of PHB under continuous light as well under a day-night regime. When grown in nitrogen and phosphorus depleted medium, the cells produced up to 63% per CDW. Upon the addition of acetate, the content was further increased to 81% per CDW. The produced polymer consists of pure PHB, which is highly isotactic. CONCLUSION The amounts of PHB achieved with PPT1 are the highest ever reported in any known cyanobacterium and demonstrate the potential of cyanobacteria for a sustainable, industrial production of PHB.
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Affiliation(s)
- Moritz Koch
- Interfaculty Institute of Microbiology and Infection Medicine Tübingen, Eberhard-Karls-Universität Tübingen, Tübingen, Germany
| | - Jonas Bruckmoser
- Wacker-Chair of Macromolecular Chemistry, TUM Department of Chemistry, Technical University of Munich, Munich, Germany
| | - Jörg Scholl
- Interfaculty Institute of Microbiology and Infection Medicine Tübingen, Eberhard-Karls-Universität Tübingen, Tübingen, Germany
| | - Waldemar Hauf
- Interfaculty Institute of Microbiology and Infection Medicine Tübingen, Eberhard-Karls-Universität Tübingen, Tübingen, Germany
| | - Bernhard Rieger
- Wacker-Chair of Macromolecular Chemistry, TUM Department of Chemistry, Technical University of Munich, Munich, Germany
| | - Karl Forchhammer
- Interfaculty Institute of Microbiology and Infection Medicine Tübingen, Eberhard-Karls-Universität Tübingen, Tübingen, Germany.
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Barone GD, Ferizović D, Biundo A, Lindblad P. Hints at the Applicability of Microalgae and Cyanobacteria for the Biodegradation of Plastics. Sustainability 2020; 12:10449. [DOI: 10.3390/su122410449] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Massive plastic accumulation has been taking place across diverse landscapes since the 1950s, when large-scale plastic production started. Nowadays, societies struggle with continuously increasing concerns about the subsequent pollution and environmental stresses that have accompanied this plastic revolution. Degradation of used plastics is highly time-consuming and causes volumetric aggregation, mainly due to their high strength and bulky structure. The size of these agglomerations in marine and freshwater basins increases daily. Exposure to weather conditions and environmental microflora (e.g., bacteria and microalgae) can slowly corrode the plastic structure. As has been well documented in recent years, plastic fragments are widespread in marine basins and partially in main global rivers. These are potential sources of negative effects on global food chains. Cyanobacteria (e.g., Synechocystis sp. PCC 6803, and Synechococcus elongatus PCC 7942), which are photosynthetic microorganisms and were previously identified as blue-green algae, are currently under close attention for their abilities to capture solar energy and the greenhouse gas carbon dioxide for the production of high-value products. In the last few decades, these microorganisms have been exploited for different purposes (e.g., biofuels, antioxidants, fertilizers, and ‘superfood’ production). Microalgae (e.g., Chlamydomonas reinhardtii, and Phaeodactylum tricornutum) are also suitable for environmental and biotechnological applications based on the exploitation of solar light. Can photosynthetic bacteria and unicellular eukaryotic algae play a role for further scientific research in the bioremediation of plastics of different sizes present in water surfaces? In recent years, several studies have been targeting the utilization of microorganisms for plastic bioremediation. Among the different phyla, the employment of wild-type or engineered cyanobacteria may represent an interesting, environmentally friendly, and sustainable option.
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Ciebiada M, Kubiak K, Daroch M. Modifying the Cyanobacterial Metabolism as a Key to Efficient Biopolymer Production in Photosynthetic Microorganisms. Int J Mol Sci 2020; 21:E7204. [PMID: 33003478 DOI: 10.3390/ijms21197204] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2020] [Revised: 09/26/2020] [Accepted: 09/28/2020] [Indexed: 12/22/2022] Open
Abstract
Cyanobacteria are photoautotrophic bacteria commonly found in the natural environment. Due to the ecological benefits associated with the assimilation of carbon dioxide from the atmosphere and utilization of light energy, they are attractive hosts in a growing number of biotechnological processes. Biopolymer production is arguably one of the most critical areas where the transition from fossil-derived chemistry to renewable chemistry is needed. Cyanobacteria can produce several polymeric compounds with high applicability such as glycogen, polyhydroxyalkanoates, or extracellular polymeric substances. These important biopolymers are synthesized using precursors derived from central carbon metabolism, including the tricarboxylic acid cycle. Due to their unique metabolic properties, i.e., light harvesting and carbon fixation, the molecular and genetic aspects of polymer biosynthesis and their relationship with central carbon metabolism are somehow different from those found in heterotrophic microorganisms. A greater understanding of the processes involved in cyanobacterial metabolism is still required to produce these molecules more efficiently. This review presents the current state of the art in the engineering of cyanobacterial metabolism for the efficient production of these biopolymers.
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Veaudor T, Blanc-Garin V, Chenebault C, Diaz-Santos E, Sassi JF, Cassier-Chauvat C, Chauvat F. Recent Advances in the Photoautotrophic Metabolism of Cyanobacteria: Biotechnological Implications. Life (Basel) 2020; 10:life10050071. [PMID: 32438704 PMCID: PMC7281370 DOI: 10.3390/life10050071] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 05/16/2020] [Accepted: 05/18/2020] [Indexed: 12/13/2022] Open
Abstract
Cyanobacteria constitute the only phylum of oxygen-evolving photosynthetic prokaryotes that shaped the oxygenic atmosphere of our planet. Over time, cyanobacteria have evolved as a widely diverse group of organisms that have colonized most aquatic and soil ecosystems of our planet and constitute a large proportion of the biomass that sustains the biosphere. Cyanobacteria synthesize a vast array of biologically active metabolites that are of great interest for human health and industry, and several model cyanobacteria can be genetically manipulated. Hence, cyanobacteria are regarded as promising microbial factories for the production of chemicals from highly abundant natural resources, e.g., solar energy, CO2, minerals, and waters, eventually coupled to wastewater treatment to save costs. In this review, we summarize new important discoveries on the plasticity of the photoautotrophic metabolism of cyanobacteria, emphasizing the coordinated partitioning of carbon and nitrogen towards growth or compound storage, and the importance of these processes for biotechnological perspectives. We also emphasize the importance of redox regulation (including glutathionylation) on these processes, a subject which has often been overlooked.
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Affiliation(s)
- Théo Veaudor
- Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, CEA, CNRS, 91198 Gif-sur-Yvette, France; (T.V.); (V.B.-G.); (C.C.); (E.D.-S.); (C.C.-C.)
| | - Victoire Blanc-Garin
- Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, CEA, CNRS, 91198 Gif-sur-Yvette, France; (T.V.); (V.B.-G.); (C.C.); (E.D.-S.); (C.C.-C.)
| | - Célia Chenebault
- Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, CEA, CNRS, 91198 Gif-sur-Yvette, France; (T.V.); (V.B.-G.); (C.C.); (E.D.-S.); (C.C.-C.)
| | - Encarnación Diaz-Santos
- Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, CEA, CNRS, 91198 Gif-sur-Yvette, France; (T.V.); (V.B.-G.); (C.C.); (E.D.-S.); (C.C.-C.)
| | - Jean-François Sassi
- Commissariat à l’énergie atomique et aux énergies alternatives (CEA), Centre de Cadarache St Paul Lez, 13108 Durance, France;
| | - Corinne Cassier-Chauvat
- Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, CEA, CNRS, 91198 Gif-sur-Yvette, France; (T.V.); (V.B.-G.); (C.C.); (E.D.-S.); (C.C.-C.)
| | - Franck Chauvat
- Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, CEA, CNRS, 91198 Gif-sur-Yvette, France; (T.V.); (V.B.-G.); (C.C.); (E.D.-S.); (C.C.-C.)
- Correspondence: ; Tel.: +33-1-69-08-78-11
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