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Nomura T, Kim J, Ishikawa M, Suzuki K, Mochida K. High-efficiency genome editing by Cas12a ribonucleoprotein complex in Euglena gracilis. Microb Biotechnol 2024; 17:e14393. [PMID: 38332568 PMCID: PMC10884871 DOI: 10.1111/1751-7915.14393] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Revised: 11/18/2023] [Accepted: 12/19/2023] [Indexed: 02/10/2024] Open
Abstract
Transgene-free genome editing based on clustered regularly interspaced short palindromic repeats (CRISPR) technology is key to achieving genetic engineering in microalgae for basic research and industrial applications. Euglena gracilis, a unicellular phytoflagellate microalga, is a promising biomaterial for foods, feeds, cosmetics and biofuels. However, methods for the genetic manipulation of E. gracilis are still limited. Here, we developed a high-efficiency, transgene-free genome editing method for E. gracilis using Lachnospiraceae bacterium CRISPR-associated protein 12a (LbCas12a) ribonucleoprotein (RNP) complex, which complements the previously established Cas9 RNP-based method. Through the direct delivery of LbCas12a-containing RNPs, our method reached mutagenesis rates of approximately 77.2-94.5% at two different E. gracilis target genes, Glucan synthase-like 2 (EgGSL2) and a phytoene synthase gene (EgcrtB). Moreover, in addition to targeted mutagenesis, we demonstrated efficient knock-in and base editing at the target site using LbCas12a-based RNPs with a single-stranded DNA donor template in E. gracilis. This study extends the genetic engineering capabilities of Euglena to accelerate its basic use for research and engineering for bioproduction.
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Affiliation(s)
- Toshihisa Nomura
- RIKEN Center for Sustainable Resource ScienceYokohamaJapan
- RIKEN Baton Zone ProgramYokohamaJapan
- Faculty of AgricultureYamagata UniversityTsuruokaJapan
| | - June‐Silk Kim
- RIKEN Center for Sustainable Resource ScienceYokohamaJapan
- Institute of Plant Science and ResourcesOkayama UniversityOkayamaJapan
| | - Marumi Ishikawa
- RIKEN Baton Zone ProgramYokohamaJapan
- Euglena Co., Ltd.TokyoJapan
| | - Kengo Suzuki
- RIKEN Baton Zone ProgramYokohamaJapan
- Euglena Co., Ltd.TokyoJapan
| | - Keiichi Mochida
- RIKEN Center for Sustainable Resource ScienceYokohamaJapan
- RIKEN Baton Zone ProgramYokohamaJapan
- Kihara Institute for Biological ResearchYokohama City UniversityYokohamaKanagawaJapan
- Graduate School of NanobioscienceYokohama City UniversityYokohamaKanagawaJapan
- School of Information and Data SciencesNagasaki UniversityNagasakiJapan
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Gain G, Berne N, Feller T, Godaux D, Cenci U, Cardol P. Induction of photosynthesis under anoxic condition in Thalassiosira pseudonana and Euglena gracilis: interactions between fermentation and photosynthesis. FRONTIERS IN PLANT SCIENCE 2023; 14:1186926. [PMID: 37560033 PMCID: PMC10407231 DOI: 10.3389/fpls.2023.1186926] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Accepted: 06/28/2023] [Indexed: 08/11/2023]
Abstract
INTRODUCTION In their natural environment, microalgae can be transiently exposed to hypoxic or anoxic environments. Whereas fermentative pathways and their interactions with photosynthesis are relatively well characterized in the green alga model Chlamydomonas reinhardtii, little information is available in other groups of photosynthetic micro-eukaryotes. In C. reinhardtii cyclic electron flow (CEF) around photosystem (PS) I, and light-dependent oxygen-sensitive hydrogenase activity both contribute to restoring photosynthetic linear electron flow (LEF) in anoxic conditions. METHODS Here we analyzed photosynthetic electron transfer after incubation in dark anoxic conditions (up to 24 h) in two secondary microalgae: the marine diatom Thalassiosira pseudonana and the excavate Euglena gracilis. RESULTS Both species showed sustained abilities to prevent over-reduction of photosynthetic electron carriers and to restore LEF. A high and transient CEF around PSI was also observed specifically in anoxic conditions at light onset in both species. In contrast, at variance with C. reinhardtii, no sustained hydrogenase activity was detected in anoxic conditions in both species. DISCUSSION Altogether our results suggest that another fermentative pathway might contribute, along with CEF around PSI, to restore photosynthetic activity in anoxic conditions in E. gracilis and T. pseudonana. We discuss the possible implication of the dissimilatory nitrate reduction to ammonium (DNRA) in T. pseudonana and the wax ester fermentation in E. gracilis.
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Affiliation(s)
- Gwenaëlle Gain
- InBioS – PhytoSYSTEMS, Laboratoire de Génétique et Physiologie des Microalgues, ULiège, Liège, Belgium
| | - Nicolas Berne
- InBioS – PhytoSYSTEMS, Laboratoire de Génétique et Physiologie des Microalgues, ULiège, Liège, Belgium
| | - Tom Feller
- InBioS – PhytoSYSTEMS, Laboratoire de Génétique et Physiologie des Microalgues, ULiège, Liège, Belgium
| | - Damien Godaux
- InBioS – PhytoSYSTEMS, Laboratoire de Génétique et Physiologie des Microalgues, ULiège, Liège, Belgium
| | - Ugo Cenci
- Unité de Glycobiologie Structurale et Fonctionnelle, Université de Lille, CNRS, UMR8576 – UGSF, Lille, France
| | - Pierre Cardol
- InBioS – PhytoSYSTEMS, Laboratoire de Génétique et Physiologie des Microalgues, ULiège, Liège, Belgium
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Takahashi Y, Shimamoto K, Toyokawa C, Suzuki K, Osanai T. Gravity sedimentation of eukaryotic algae Euglena gracilis accelerated by ethanol cultivation. Appl Microbiol Biotechnol 2023; 107:3021-3032. [PMID: 36941437 DOI: 10.1007/s00253-023-12476-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Revised: 03/02/2023] [Accepted: 03/06/2023] [Indexed: 03/23/2023]
Abstract
Euglena gracilis (E. gracilis) is a unicellular microalga with various applications in medicine, agriculture, aquaculture, health supplement, and jet fuel production. Euglena possibly solves population growth and exhaustion of fossil resources. Efficient cell harvesting is needed for the industry, and the gravity sedimentation method is low cost and does not require any equipment, although it has low efficiency. This study showed that the gravity sedimentation of E. gracilis cells is improved by cultivation in the presence of ethanol (EtOH). The gravity sedimentation of E. gracilis cells cultivated under 0.5% or 1.0% EtOH conditions was faster than that cultivated without EtOH. The mean calculated cell diameter was also found to be largest in cells cultivated under 0.5% or 1.0% EtOH conditions compared to that in cells cultivated without EtOH. Intracellular paramylon content, cell shapes, and motility differed between cells cultivated under 0.5% or 1.0% EtOH conditions and in the absence of EtOH. The results suggest that E. gracilis cultivation with EtOH leads to increased cell productivity, paramylon production, and efficient cell harvesting. KEY POINTS: • Euglena gracilis is an edible microalga producing value-added metabolites. • Ethanol addition upregulates E. gracilis growth and paramylon accumulation. • Gravity sedimentation is accelerated by ethanol-grown E. gracilis cells.
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Affiliation(s)
- Yu Takahashi
- School of Agriculture, Meiji University, 1-1-1 Higashimita, Tama-Ku, Kawasaki, Kanagawa, 214-8571, Japan
| | - Kosuke Shimamoto
- School of Agriculture, Meiji University, 1-1-1 Higashimita, Tama-Ku, Kawasaki, Kanagawa, 214-8571, Japan
| | - Chihana Toyokawa
- euglena Co., Ltd., 5-33-1 Shiba, Minato-Ku, Tokyo, 108-0014, Japan
- RIKEN, 1-7-22, Suehirocho, Tsurumi-Ku, Yokohama, Kanagawa, 230-0045, Japan
| | - Kengo Suzuki
- euglena Co., Ltd., 5-33-1 Shiba, Minato-Ku, Tokyo, 108-0014, Japan
- RIKEN, 1-7-22, Suehirocho, Tsurumi-Ku, Yokohama, Kanagawa, 230-0045, Japan
| | - Takashi Osanai
- School of Agriculture, Meiji University, 1-1-1 Higashimita, Tama-Ku, Kawasaki, Kanagawa, 214-8571, Japan.
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Kim S, Im H, Yu J, Kim K, Kim M, Lee T. Biofuel production from Euglena: Current status and techno-economic perspectives. BIORESOURCE TECHNOLOGY 2023; 371:128582. [PMID: 36610485 DOI: 10.1016/j.biortech.2023.128582] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 01/02/2023] [Accepted: 01/03/2023] [Indexed: 06/17/2023]
Abstract
Sustainable aviation fuels (SAFs) can contribute reduce greenhouse gas emissions compared to conventional fuel. With the increasing SAFs demand, various generations of resources have been shifted from the 1st generation (oil crops), the 2nd generation (agricultural waste), to the 3rd generation (microalgae). Microalgae are the most suitable feedstock for jet biofuel production than other resources because of their productivity and capability to capture carbon dioxide. However, microalgae-based biofuel has a limitation of high freezing point. Recently, a jet biofuel derived from Euglena wax ester has been paying attention due to its low freezing point. Challenges still remain to enhance production yields in both upstream and downstream processes. Studies on downstream processes as well as techno-economic analysis on biofuel production using Euglena are highly limited to date. Economic aspects for the biofuel production will be ensured via valorization of industrial byproducts such as food wastes.
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Affiliation(s)
- Sunah Kim
- Department of Civil and Environmental Engineering, Pusan National University, Busan 46241, Republic of Korea
| | - Hyungjoon Im
- Institute for Environment and Energy, Pusan National University, Busan 46241, Republic of Korea
| | - Jaecheul Yu
- Department of Civil and Environmental Engineering, Pusan National University, Busan 46241, Republic of Korea; Institute for Environment and Energy, Pusan National University, Busan 46241, Republic of Korea
| | - Keunho Kim
- Department of Civil and Environmental Engineering, Pusan National University, Busan 46241, Republic of Korea
| | - Minjeong Kim
- Department of Civil and Environmental Engineering, Pusan National University, Busan 46241, Republic of Korea
| | - Taeho Lee
- Department of Civil and Environmental Engineering, Pusan National University, Busan 46241, Republic of Korea.
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Ishikawa M, Nomura T, Tamaki S, Ozasa K, Suzuki T, Toyooka K, Hirota K, Yamada K, Suzuki K, Mochida K. CRISPR/Cas9-mediated generation of non-motile mutants to improve the harvesting efficiency of mass-cultivated Euglena gracilis. PLANT BIOTECHNOLOGY JOURNAL 2022; 20:2042-2044. [PMID: 35916139 PMCID: PMC9616515 DOI: 10.1111/pbi.13904] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Revised: 07/22/2022] [Accepted: 07/28/2022] [Indexed: 06/15/2023]
Affiliation(s)
- Marumi Ishikawa
- Microalgae Production Control Technology Laboratory, RIKEN Baton Zone Program, RIKEN Cluster for ScienceTechnology and Innovation HubYokohamaJapan
| | - Toshihisa Nomura
- Microalgae Production Control Technology Laboratory, RIKEN Baton Zone Program, RIKEN Cluster for ScienceTechnology and Innovation HubYokohamaJapan
- Bioproductivity Informatics Research TeamRIKEN Center for Sustainable Resource ScienceYokohamaJapan
| | - Shun Tamaki
- Microalgae Production Control Technology Laboratory, RIKEN Baton Zone Program, RIKEN Cluster for ScienceTechnology and Innovation HubYokohamaJapan
| | - Kazunari Ozasa
- Advanced Laser Processing Research TeamRIKEN Center for Advanced PhotonicsWakoJapan
| | - Tomoko Suzuki
- Mass Spectrometry and Microscopy Unit, Technology Platform DivisionRIKEN Center for Sustainable Resource ScienceKanagawaJapan
- Center for Gene ResearchNagoya UniversityAichiJapan
| | - Kiminori Toyooka
- Mass Spectrometry and Microscopy Unit, Technology Platform DivisionRIKEN Center for Sustainable Resource ScienceKanagawaJapan
| | - Kikue Hirota
- Microalgae Production Control Technology Laboratory, RIKEN Baton Zone Program, RIKEN Cluster for ScienceTechnology and Innovation HubYokohamaJapan
| | - Koji Yamada
- Microalgae Production Control Technology Laboratory, RIKEN Baton Zone Program, RIKEN Cluster for ScienceTechnology and Innovation HubYokohamaJapan
- euglena Co., Ltd.TokyoJapan
| | - Kengo Suzuki
- Microalgae Production Control Technology Laboratory, RIKEN Baton Zone Program, RIKEN Cluster for ScienceTechnology and Innovation HubYokohamaJapan
- euglena Co., Ltd.TokyoJapan
| | - Keiichi Mochida
- Microalgae Production Control Technology Laboratory, RIKEN Baton Zone Program, RIKEN Cluster for ScienceTechnology and Innovation HubYokohamaJapan
- Bioproductivity Informatics Research TeamRIKEN Center for Sustainable Resource ScienceYokohamaJapan
- Kihara Institute for Biological ResearchYokohama City UniversityYokohamaJapan
- Graduate School of NanobioscienceYokohama City UniversityYokohamaJapan
- School of Information and Data SciencesNagasaki UniversityNagasakiJapan
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Tanaka Y, Goto K, Jun L, Nishino K, Ogawa T, Maruta T, Ishikawa T. Identification of glucanases and phosphorylases involved in hypoxic paramylon degradation in Euglena gracilis. ALGAL RES 2022. [DOI: 10.1016/j.algal.2022.102829] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Kaszecki E, Kennedy V, Shah M, Maciszewski K, Karnkowska A, Linton E, Ginger ML, Farrow S, Ebenezer TE. Meeting Report: Euglenids in the Age of Symbiogenesis: Origins, Innovations, and Prospects, November 8-11, 2021. Protist 2022; 173:125894. [PMID: 35772300 DOI: 10.1016/j.protis.2022.125894] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2022] [Revised: 06/01/2022] [Accepted: 06/02/2022] [Indexed: 10/18/2022]
Affiliation(s)
- Emma Kaszecki
- Environmental and Life Sciences Graduate Program, Trent University, Peterborough, ON K9J 7B8, Canada
| | - Victoria Kennedy
- Environmental and Life Sciences Graduate Program, Trent University, Peterborough, ON K9J 7B8, Canada
| | - Mahfuzur Shah
- Department of Cell Biology, Metabolism and Systems Biology, Noblegen Inc., 2140 East Bank Dr, Peterborough, ON, Canada
| | - Kacper Maciszewski
- Institute of Evolutionary Biology, Faculty of Biology, Biological and Chemical Research Centre, University of Warsaw, Żwirki i Wigury 101, 02-089 Warsaw, Poland
| | - Anna Karnkowska
- Institute of Evolutionary Biology, Faculty of Biology, Biological and Chemical Research Centre, University of Warsaw, Żwirki i Wigury 101, 02-089 Warsaw, Poland
| | - Eric Linton
- Central Michigan University, Department of Biology, Mount Pleasant, MI 48859, USA
| | - Michael L Ginger
- School of Applied Sciences, University of Huddersfield, Queensgate, Huddersfield HD1 3DH, UK.
| | - Scott Farrow
- Department of Cell Biology, Metabolism and Systems Biology, Noblegen Inc., 2140 East Bank Dr, Peterborough, ON, Canada
| | - ThankGod Echezona Ebenezer
- European Molecular Biology Laboratory, European Bioinformatics Institute (EMBL-EBI), Hinxton, Cambridgeshire CB10 1SD, UK
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Chen Z, Zhu J, Du M, Chen Z, Liu Q, Zhu H, Lei A, Wang J. A Synthetic Biology Perspective on the Bioengineering Tools for an Industrial Microalga: Euglena gracilis. Front Bioeng Biotechnol 2022; 10:882391. [PMID: 35464731 PMCID: PMC9020809 DOI: 10.3389/fbioe.2022.882391] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Accepted: 03/11/2022] [Indexed: 11/13/2022] Open
Abstract
Euglena is a genus of single-celled eukaryotes that show both plant- and animal-like characteristics. Euglena gracilis, a model species, is of great academic interest for studying endosymbiosis and chloroplast development. As an industrial species, E. gracilis is also of primary biotechnological and economic importance as high value-added food, medicine, and cosmetic and high-quality feedstock for jet-fuel production because of its cells containing many high-value products, such as vitamins, amino acids, pigments, unsaturated fatty acids, and carbohydrate paramylon, as metabolites. For more than half a century, E. gracilis has been used as an industrial biotechnology platform for fundamental biology research, mainly exploring relevant physiological and biochemical method studies. Although many researchers focused on genetic engineering tools for E. gracilis in recent years, little progress has been achieved because of the lack of high-quality genome information and efficient techniques for genetic operation. This article reviewed the progress of the genetic transformation of E. gracilis, including methods for the delivery of exogenous materials and other advanced biotechnological tools for E. gracilis, such as CRISPR and RNA interference. We hope to provide a reference to improve the research in functional genomics and synthetic biology of Euglena.
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Affiliation(s)
- Zhenfan Chen
- College of Food Engineering and Biotechnology, Hanshan Normal University, Chaozhou, China
- Shenzhen Key Laboratory of Marine Bioresource and Eco-Environmental Science, Shenzhen Engineering Laboratory for Marine Algal Biotechnology, Guangdong Provincial Key Laboratory for Plant Epigenetics, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, China
- Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University, Shenzhen, China
| | - Jiayi Zhu
- Shenzhen Key Laboratory of Marine Bioresource and Eco-Environmental Science, Shenzhen Engineering Laboratory for Marine Algal Biotechnology, Guangdong Provincial Key Laboratory for Plant Epigenetics, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, China
| | - Ming Du
- Shenzhen Key Laboratory of Marine Bioresource and Eco-Environmental Science, Shenzhen Engineering Laboratory for Marine Algal Biotechnology, Guangdong Provincial Key Laboratory for Plant Epigenetics, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, China
| | - Zixi Chen
- Shenzhen Key Laboratory of Marine Bioresource and Eco-Environmental Science, Shenzhen Engineering Laboratory for Marine Algal Biotechnology, Guangdong Provincial Key Laboratory for Plant Epigenetics, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, China
| | - Qiong Liu
- Shenzhen Key Laboratory of Marine Bioresource and Eco-Environmental Science, Shenzhen Engineering Laboratory for Marine Algal Biotechnology, Guangdong Provincial Key Laboratory for Plant Epigenetics, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, China
- Shenzhen-Hong Kong Institute of Brain Science, Shenzhen, China
| | - Hui Zhu
- College of Food Engineering and Biotechnology, Hanshan Normal University, Chaozhou, China
| | - Anping Lei
- Shenzhen Key Laboratory of Marine Bioresource and Eco-Environmental Science, Shenzhen Engineering Laboratory for Marine Algal Biotechnology, Guangdong Provincial Key Laboratory for Plant Epigenetics, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, China
| | - Jiangxin Wang
- Shenzhen Key Laboratory of Marine Bioresource and Eco-Environmental Science, Shenzhen Engineering Laboratory for Marine Algal Biotechnology, Guangdong Provincial Key Laboratory for Plant Epigenetics, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, China
- *Correspondence: Jiangxin Wang,
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9
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Blasio M, Balzano S. Fatty Acids Derivatives From Eukaryotic Microalgae, Pathways and Potential Applications. Front Microbiol 2021; 12:718933. [PMID: 34659147 PMCID: PMC8511707 DOI: 10.3389/fmicb.2021.718933] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Accepted: 08/24/2021] [Indexed: 11/13/2022] Open
Abstract
The exploitation of petrochemical hydrocarbons is compromising ecosystem and human health and biotechnological research is increasingly focusing on sustainable materials from plants and, to a lesser extent, microalgae. Fatty acid derivatives include, among others, oxylipins, hydroxy fatty acids, diols, alkenones, and wax esters. They can occur as storage lipids or cell wall components and possess, in some cases, striking cosmeceutical, pharmaceutical, and nutraceutical properties. In addition, long chain (>20) fatty acid derivatives mostly contain highly reduced methylenic carbons and exhibit a combustion enthalpy higher than that of C14–20 fatty acids, being potentially suitable as biofuel candidates. Finally, being the building blocks of cell wall components, some fatty acid derivatives might also be used as starters for the industrial synthesis of different polymers. Within this context, microalgae can be a promising source of fatty acid derivatives and, in contrast with terrestrial plants, do not require arable land neither clean water for their growth. Microalgal mass culturing for the extraction and the exploitation of fatty acid derivatives, along with products that are relevant in nutraceutics (e.g., polyunsaturated fatty acids), might contribute in increasing the viability of microalgal biotechnologies. This review explores fatty acids derivatives from microalgae with applications in the field of renewable energies, biomaterials and pharmaceuticals. Nannochloropsis spp. (Eustigmatophyceae, Heterokontophyta) are particularly interesting for biotechnological applications since they grow at faster rates than many other species and possess hydroxy fatty acids and aliphatic cell wall polymers.
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Affiliation(s)
- Martina Blasio
- Department of Marine Biotechnologies, Stazione Zoologica Anton Dohrn Napoli (SZN), Naples, Italy
| | - Sergio Balzano
- Department of Marine Biotechnologies, Stazione Zoologica Anton Dohrn Napoli (SZN), Naples, Italy.,Department of Marine Microbiology and Biogeochemistry, Royal Netherlands Institute for Sea Research (NIOZ), Den Burg (Texel), Netherlands
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10
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Kim DH, Kim JY, Oh JJ, Jeon MS, An HS, Jin CR, Choi YE. A strategic approach to apply bacterial substances for increasing metabolite productions of Euglena gracilis in the bioreactor. Appl Microbiol Biotechnol 2021; 105:5395-5406. [PMID: 34173846 DOI: 10.1007/s00253-021-11412-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 05/20/2021] [Accepted: 06/11/2021] [Indexed: 12/01/2022]
Abstract
Bacterial extracellular polymeric substances (EPS) are promising materials that have a role in enhancing growth, metabolite production, and harvesting efficiency. However, the validity of the EPS effectiveness in scale-up cultivation of microalgae is still unknown. Therefore, in order to verify whether the bacterial metabolites work in the scale-up fermentation of microalgae, we conducted a bioreactor fermentation following the addition of bacterial EPS derived from the marine bacterium, Pseudoalteromonas sp., to Euglena gracilis. Various culture strategies (i.e., batch, glucose fed-batch, and glucose and EPS fed-batch) were conducted to maximize metabolite production of E. gracilis in scale-up cultivation. Consequently, biomass and paramylon concentrations in the continuous glucose and EPS-treated culture were enhanced by 3.0-fold and 4.2-fold (36.1 ± 1.4 g L-1 and 25.6 ± 0.1 g L-1), respectively, compared to the non-treated control (12.0 ± 0.3 g L-1 and 6.1 ± 0.1 g L-1). Also, the supplementation led to the enhanced concentrations of α-tocopherols and total fatty acids by 3.7-fold and 2.8-fold, respectively. The harvesting efficiency was enhanced in EPS-supplemented cultivation due to the flocculation of E. gracilis. To the best of our knowledge, this is the first study that verifies the effect of bacterial EPS in scale-up cultivation of microalgae. Also, our results showed the highest paramylon productivity than any other previous reports. The results obtained in this study showed that the scale-up cultivation of E. gracilis using bacterial EPS has the potential to be used as a platform to guide further increases in scale and in the industrial environment. KEY POINTS: Effect of EPS on Euglena gracilis fermentation was tested in bioreactor scale. EPS supplement was effective for the paramylon, α-tocopherol, and lipid production. EPS supplement induced the flocculation of E. gracilis.
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Affiliation(s)
- Da Hee Kim
- Division of Environmental Science & Ecological Engineering, Korea University, Seoul, 02841, Republic of Korea
| | - Jee Young Kim
- Division of Environmental Science & Ecological Engineering, Korea University, Seoul, 02841, Republic of Korea
| | - Jeong-Joo Oh
- Division of Environmental Science & Ecological Engineering, Korea University, Seoul, 02841, Republic of Korea
| | - Min Seo Jeon
- Division of Environmental Science & Ecological Engineering, Korea University, Seoul, 02841, Republic of Korea
| | - Hye Suck An
- Marine Biology Research Division, National Marine Biodiversity Institute of Korea, Chungcheongnam-do, Seocheon, 33662, Republic of Korea
| | - Cho Rok Jin
- Division of Environmental Science & Ecological Engineering, Korea University, Seoul, 02841, Republic of Korea
| | - Yoon-E Choi
- Division of Environmental Science & Ecological Engineering, Korea University, Seoul, 02841, Republic of Korea.
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Cordoba J, Perez E, Van Vlierberghe M, Bertrand AR, Lupo V, Cardol P, Baurain D. De Novo Transcriptome Meta-Assembly of the Mixotrophic Freshwater Microalga Euglena gracilis. Genes (Basel) 2021; 12:842. [PMID: 34072576 PMCID: PMC8227486 DOI: 10.3390/genes12060842] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 05/24/2021] [Accepted: 05/27/2021] [Indexed: 01/01/2023] Open
Abstract
Euglena gracilis is a well-known photosynthetic microeukaryote considered as the product of a secondary endosymbiosis between a green alga and a phagotrophic unicellular belonging to the same eukaryotic phylum as the parasitic trypanosomatids. As its nuclear genome has proven difficult to sequence, reliable transcriptomes are important for functional studies. In this work, we assembled a new consensus transcriptome by combining sequencing reads from five independent studies. Based on a detailed comparison with two previously released transcriptomes, our consensus transcriptome appears to be the most complete so far. Remapping the reads on it allowed us to compare the expression of the transcripts across multiple culture conditions at once and to infer a functionally annotated network of co-expressed genes. Although the emergence of meaningful gene clusters indicates that some biological signal lies in gene expression levels, our analyses confirm that gene regulation in euglenozoans is not primarily controlled at the transcriptional level. Regarding the origin of E. gracilis, we observe a heavily mixed gene ancestry, as previously reported, and rule out sequence contamination as a possible explanation for these observations. Instead, they indicate that this complex alga has evolved through a convoluted process involving much more than two partners.
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Affiliation(s)
- Javier Cordoba
- InBioS—PhytoSYSTEMS, Laboratoire de Génétique et Physiologie des Microalgues, ULiège, B-4000 Liège, Belgium; (J.C.); (E.P.); (P.C.)
| | - Emilie Perez
- InBioS—PhytoSYSTEMS, Laboratoire de Génétique et Physiologie des Microalgues, ULiège, B-4000 Liège, Belgium; (J.C.); (E.P.); (P.C.)
- InBioS—PhytoSYSTEMS, Unit of Eukaryotic Phylogenomics, ULiège, B-4000 Liège, Belgium; (M.V.V.); (A.R.B.); (V.L.)
| | - Mick Van Vlierberghe
- InBioS—PhytoSYSTEMS, Unit of Eukaryotic Phylogenomics, ULiège, B-4000 Liège, Belgium; (M.V.V.); (A.R.B.); (V.L.)
| | - Amandine R. Bertrand
- InBioS—PhytoSYSTEMS, Unit of Eukaryotic Phylogenomics, ULiège, B-4000 Liège, Belgium; (M.V.V.); (A.R.B.); (V.L.)
| | - Valérian Lupo
- InBioS—PhytoSYSTEMS, Unit of Eukaryotic Phylogenomics, ULiège, B-4000 Liège, Belgium; (M.V.V.); (A.R.B.); (V.L.)
| | - Pierre Cardol
- InBioS—PhytoSYSTEMS, Laboratoire de Génétique et Physiologie des Microalgues, ULiège, B-4000 Liège, Belgium; (J.C.); (E.P.); (P.C.)
| | - Denis Baurain
- InBioS—PhytoSYSTEMS, Unit of Eukaryotic Phylogenomics, ULiège, B-4000 Liège, Belgium; (M.V.V.); (A.R.B.); (V.L.)
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Research progress and the biotechnological applications of multienzyme complex. Appl Microbiol Biotechnol 2021; 105:1759-1777. [PMID: 33564922 DOI: 10.1007/s00253-021-11121-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2020] [Revised: 01/07/2021] [Accepted: 01/16/2021] [Indexed: 11/26/2022]
Abstract
The multienzyme complex system has become a research focus in synthetic biology due to its highly efficient overall catalytic ability and has been applied to various fields. Multienzyme complexes are formed by cascading complexes, which are multiple functionally related enzymes that continuously and efficiently catalyze the production of substrates. Compared with current mainstream microbial cell catalytic systems, in vitro multienzyme molecular machines have many advantages, such as fewer side reactions, a high product yield, a fast reaction speed, easy product separation, a tolerable toxic environment, and robust system operability, showing increasing competitiveness in the field of biomanufacturing. In this review, the research progress of multienzyme complexes in nature and multienzyme cascades in vivo or in vitro will be introduced, and the discovered enzyme cascades concerning scaffolding proteins will also be discussed. This review is expected to provide a more theoretical basis for the modification of multienzyme complexes and broaden their application in the field of synthetic biology. KEY POINTS: • The cascade reactions of some natural multienzyme complexes are reviewed. • The main approaches of constructing artificial multienzyme complexes are summarized. • The structure and application of cellulosomes are discussed and prospected.
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Muramatsu S, Atsuji K, Yamada K, Ozasa K, Suzuki H, Takeuchi T, Hashimoto-Marukawa Y, Kazama Y, Abe T, Suzuki K, Iwata O. Isolation and characterization of a motility-defective mutant of Euglena gracilis. PeerJ 2020; 8:e10002. [PMID: 33062431 PMCID: PMC7528813 DOI: 10.7717/peerj.10002] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Accepted: 08/30/2020] [Indexed: 12/15/2022] Open
Abstract
Euglena gracilis is a green photosynthetic microalga that swims using its flagellum. This species has been used as a model organism for over half a century to study its metabolism and the mechanisms of its behavior. The development of mass-cultivation technology has led to E. gracilis application as a feedstock in various products such as foods. Therefore, breeding of E. gracilis has been attempted to improve the productivity of this feedstock for potential industrial applications. For this purpose, a characteristic that preserves the microalgal energy e.g., reduces motility, should be added to the cultivars. The objective of this study was to verify our hypothesis that E. gracilis locomotion-defective mutants are suitable for industrial applications because they save the energy required for locomotion. To test this hypothesis, we screened for E. gracilis mutants from Fe-ion-irradiated cell suspensions and established a mutant strain,M 3 - ZFeL, which shows defects in flagellum formation and locomotion. The mutant strain exhibits a growth rate comparable to that of the wild type when cultured under autotrophic conditions, but had a slightly slower growth under heterotrophic conditions. It also stores 1.6 times the amount of paramylon, a crystal of β-1,3-glucan, under autotrophic culture conditions, and shows a faster sedimentation compared with that of the wild type, because of the deficiency in mobility and probably the high amount of paramylon accumulation. Such characteristics make E. gracilis mutant cells suitable for cost-effective mass cultivation and harvesting.
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Affiliation(s)
- Shuki Muramatsu
- Department of Health Science, Showa Women's University, Tokyo, Japan
- euglena Co., Ltd., Tokyo, Japan
| | - Kohei Atsuji
- euglena Co., Ltd., Tokyo, Japan
- Baton Zone Program, RIKEN, Saitama, Japan
| | - Koji Yamada
- euglena Co., Ltd., Tokyo, Japan
- Baton Zone Program, RIKEN, Saitama, Japan
| | - Kazunari Ozasa
- Bioengineering Laboratory, Cluster for Pioneering Research, RIKEN, Saitama, Japan
| | | | | | | | - Yusuke Kazama
- RIKEN Nishina Center, Saitama, Japan
- Faculty of Bioscience and Biotechnology, Fukui Prefectural University, Fukui, Japan
| | | | - Kengo Suzuki
- euglena Co., Ltd., Tokyo, Japan
- Baton Zone Program, RIKEN, Saitama, Japan
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14
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Hammond MJ, Nenarokova A, Butenko A, Zoltner M, Dobáková EL, Field MC, Lukeš J. A Uniquely Complex Mitochondrial Proteome from Euglena gracilis. Mol Biol Evol 2020; 37:2173-2191. [PMID: 32159766 PMCID: PMC7403612 DOI: 10.1093/molbev/msaa061] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Euglena gracilis is a metabolically flexible, photosynthetic, and adaptable free-living protist of considerable environmental importance and biotechnological value. By label-free liquid chromatography tandem mass spectrometry, a total of 1,786 proteins were identified from the E. gracilis purified mitochondria, representing one of the largest mitochondrial proteomes so far described. Despite this apparent complexity, protein machinery responsible for the extensive RNA editing, splicing, and processing in the sister clades diplonemids and kinetoplastids is absent. This strongly suggests that the complex mechanisms of mitochondrial gene expression in diplonemids and kinetoplastids occurred late in euglenozoan evolution, arising independently. By contrast, the alternative oxidase pathway and numerous ribosomal subunits presumed to be specific for parasitic trypanosomes are present in E. gracilis. We investigated the evolution of unexplored protein families, including import complexes, cristae formation proteins, and translation termination factors, as well as canonical and unique metabolic pathways. We additionally compare this mitoproteome with the transcriptome of Eutreptiella gymnastica, illuminating conserved features of Euglenida mitochondria as well as those exclusive to E. gracilis. This is the first mitochondrial proteome of a free-living protist from the Excavata and one of few available for protists as a whole. This study alters our views of the evolution of the mitochondrion and indicates early emergence of complexity within euglenozoan mitochondria, independent of parasitism.
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Affiliation(s)
- Michael J Hammond
- Biology Centre, Institute of Parasitology, Czech Academy of Sciences, České Budějovice, Budweis, Czech Republic
| | - Anna Nenarokova
- Biology Centre, Institute of Parasitology, Czech Academy of Sciences, České Budějovice, Budweis, Czech Republic
- Faculty of Sciences, University of South Bohemia, České Budějovice, Budweis, Czech Republic
| | - Anzhelika Butenko
- Biology Centre, Institute of Parasitology, Czech Academy of Sciences, České Budějovice, Budweis, Czech Republic
- Faculty of Science, University of Ostrava, Ostrava, Czech Republic
| | - Martin Zoltner
- School of Life Sciences, University of Dundee, Dundee, United Kingdom
- Faculty of Science, Charles University, Biocev, Vestec, Czech Republic
| | - Eva Lacová Dobáková
- Biology Centre, Institute of Parasitology, Czech Academy of Sciences, České Budějovice, Budweis, Czech Republic
| | - Mark C Field
- Biology Centre, Institute of Parasitology, Czech Academy of Sciences, České Budějovice, Budweis, Czech Republic
- School of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - Julius Lukeš
- Biology Centre, Institute of Parasitology, Czech Academy of Sciences, České Budějovice, Budweis, Czech Republic
- Faculty of Sciences, University of South Bohemia, České Budějovice, Budweis, Czech Republic
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15
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Harada R, Nomura T, Yamada K, Mochida K, Suzuki K. Genetic Engineering Strategies for Euglena gracilis and Its Industrial Contribution to Sustainable Development Goals: A Review. Front Bioeng Biotechnol 2020; 8:790. [PMID: 32760709 PMCID: PMC7371780 DOI: 10.3389/fbioe.2020.00790] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Accepted: 06/22/2020] [Indexed: 11/20/2022] Open
Abstract
The sustainable development goals (SDGs) adopted at the 2015 United Nations Summit are globally applicable goals designed to help countries realize a sustainable future. To achieve these SDGs, it is necessary to utilize renewable biological resources. In recent years, bioeconomy has been an attractive concept for achieving the SDGs. Microalgae are one of the biological resources that show promise in realizing the "5F"s (food, fiber, feed, fertilizer, and fuel). Among the microalgae, Euglena gracilis has the potential for achieving the "5F"s strategy owing to its unique features, such as production of paramylon, that are lacking in other microalgae. E. gracilis has already been produced on an industrial scale for use as an ingredient in functional foods and cosmetics. In recent years, genetic engineering methods for breeding E. gracilis have been researched and developed to achieve higher yields. In this article, we summarize how microalgae contribute toward achieving the SDGs. We focus on the contribution of E. gracilis to the bioeconomy, including its advantages in industrial use as well as its unique characteristics. In addition, we review genetic engineering-related research trends centered on E. gracilis, including a complete nuclear genome determination project, genome editing technology using the CRISPR-Cas9 system, and the development of a screening method for selecting useful strains. In particular, genome editing in E. gracilis could be a breakthrough for molecular breeding of industrially useful strains because of its high efficiency.
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Affiliation(s)
- Ryo Harada
- RIKEN Baton Zone Program, Yokohama, Japan
| | - Toshihisa Nomura
- RIKEN Baton Zone Program, Yokohama, Japan
- RIKEN Center for Sustainable Resource Science, Yokohama, Japan
| | - Koji Yamada
- RIKEN Baton Zone Program, Yokohama, Japan
- Euglena Co Ltd, Tokyo, Japan
| | - Keiichi Mochida
- RIKEN Baton Zone Program, Yokohama, Japan
- RIKEN Center for Sustainable Resource Science, Yokohama, Japan
| | - Kengo Suzuki
- RIKEN Baton Zone Program, Yokohama, Japan
- Euglena Co Ltd, Tokyo, Japan
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16
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Okada K, Fujiwara S, Tsuzuki M. Energy conservation in photosynthetic microorganisms. J GEN APPL MICROBIOL 2020; 66:59-65. [PMID: 32336724 DOI: 10.2323/jgam.2020.02.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Photosynthesis is a biological process of energy conversion from solar radiation to useful organic compounds for the photosynthetic organisms themselves. It, thereby, also plays a role of food production for almost all animals on the Earth. The utilization of photosynthesis as an artificial carbon cycle is also attracting a lot of attention regarding its benefits for human life. Hydrogen and biofuels, obtained from photosynthetic microorganisms, such as microalgae and cyanobacteria, will be promising products as energy and material resources. Considering that the efficiency of bioenergy production is insufficient to replace fossil fuels at present, techniques for the industrial utilization of photosynthesis processes need to be developed intensively. Increase in the efficiency of photosynthesis, the yields of target substances, and the growth rates of algae and cyanobacteria must be subjects for efficient industrialization. Here, we overview the whole aspect of the energy production from photosynthesis to biomass production of various photosynthetic microorganisms.
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Affiliation(s)
- Katsuhiko Okada
- School of Life Sciences, Tokyo University of Pharmacy and Life Sciences
| | - Shoko Fujiwara
- School of Life Sciences, Tokyo University of Pharmacy and Life Sciences
| | - Mikio Tsuzuki
- School of Life Sciences, Tokyo University of Pharmacy and Life Sciences
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17
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Tamaki S, Nishino K, Ogawa T, Maruta T, Sawa Y, Arakawa K, Ishikawa T. Comparative proteomic analysis of mitochondria isolated from Euglena gracilis under aerobic and hypoxic conditions. PLoS One 2019; 14:e0227226. [PMID: 31891638 PMCID: PMC6938325 DOI: 10.1371/journal.pone.0227226] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Accepted: 12/13/2019] [Indexed: 12/26/2022] Open
Abstract
The unicellular microalga Euglena gracilis produces wax esters for ATP acquisition under low-oxygen conditions. The regulatory mechanism of wax ester production is not yet understood. Indeed, our previous transcriptomic analysis showed that transcript levels of genes involved in the wax ester synthesis hardly changed under hypoxic conditions, suggesting contribution of post-transcriptional regulation. In this study, we conducted a proteome analysis of E. gracilis mitochondria, as this organelle employs the fatty-acid synthesis pathway under hypoxic conditions. Mitochondria were isolated from E. gracilis SM-ZK strain treated with both aerobic and hypoxic conditions and used for shotgun proteomic analysis. Three independent proteomic analyses succeeded in identifying a total of 714 non-redundant proteins. Of these, 229 were detected in common to all experiments, and 116 were significantly recognized as differentially expressed proteins. GO enrichment analysis suggested dynamic changes in mitochondrial metabolic pathways and redox reactions under aerobic and hypoxic conditions. Protein levels of bifunctional enzymes isocitrate lyase and malate synthase in glyoxylate cycle were 1.35-fold higher under hypoxic conditions. Abundances of the propionyl-CoA synthetic enzymes, succinyl-CoA synthetase and propionyl-CoA carboxylase, were also 1.35- and 1.47-fold higher, respectively, under hypoxic conditions. Protein levels of pyruvate:NADP+ oxidoreductase, a key enzyme for anaerobic synthesis of acetyl-CoA, which serves as a C2 donor for fatty acids, showed a 1.68-fold increase under hypoxic conditions, whereas those of pyruvate dehydrogenase subunits showed a 0.77–0.81-fold decrease. Protein levels of the fatty-acid synthesis enzymes, 3-ketoacyl-CoA thiolase isoforms (KAT1 and KAT2), 3-hydroxyacyl-CoA dehydrogenases, and acyl-CoA dehydrogenase were up-regulated by 1.20- to 1.42-fold in response to hypoxic treatment. Overall, our proteomic analysis revealed that wax ester synthesis-related enzymes are up-regulated at the protein level post-transcriptionally to promote wax ester production in E. gracilis under low-oxygen conditions.
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Affiliation(s)
- Shun Tamaki
- Institute of Agricultural and Life Sciences, Academic Assembly, Shimane University, Matsue, Shimane, Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Chiyoda-ku, Tokyo, Japan
| | - Kohei Nishino
- Institute of Agricultural and Life Sciences, Academic Assembly, Shimane University, Matsue, Shimane, Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Chiyoda-ku, Tokyo, Japan
| | - Takahisa Ogawa
- Institute of Agricultural and Life Sciences, Academic Assembly, Shimane University, Matsue, Shimane, Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Chiyoda-ku, Tokyo, Japan
| | - Takanori Maruta
- Institute of Agricultural and Life Sciences, Academic Assembly, Shimane University, Matsue, Shimane, Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Chiyoda-ku, Tokyo, Japan
| | - Yoshihiro Sawa
- Institute of Agricultural and Life Sciences, Academic Assembly, Shimane University, Matsue, Shimane, Japan
| | - Kazuharu Arakawa
- Institute for Advanced Biosciences, Keio University, Tsuruoka, Yamagata, Japan
- Systems Biology Program, Graduate School of Media and Governance, Keio University, Fujisawa, Kanagawa, Japan
| | - Takahiro Ishikawa
- Institute of Agricultural and Life Sciences, Academic Assembly, Shimane University, Matsue, Shimane, Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Chiyoda-ku, Tokyo, Japan
- * E-mail:
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18
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Nomura T, Inoue K, Uehara‐Yamaguchi Y, Yamada K, Iwata O, Suzuki K, Mochida K. Highly efficient transgene-free targeted mutagenesis and single-stranded oligodeoxynucleotide-mediated precise knock-in in the industrial microalga Euglena gracilis using Cas9 ribonucleoproteins. PLANT BIOTECHNOLOGY JOURNAL 2019; 17:2032-2034. [PMID: 31131534 PMCID: PMC6790356 DOI: 10.1111/pbi.13174] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Revised: 05/20/2019] [Accepted: 05/20/2019] [Indexed: 05/26/2023]
Affiliation(s)
- Toshihisa Nomura
- RIKEN Center for Sustainable Resource ScienceTsurumi‐ku, YokohamaJapan
- RIKEN Baton Zone ProgramTsurumi‐ku, YokohamaJapan
| | - Komaki Inoue
- RIKEN Center for Sustainable Resource ScienceTsurumi‐ku, YokohamaJapan
| | | | - Koji Yamada
- RIKEN Baton Zone ProgramTsurumi‐ku, YokohamaJapan
- euglena Co., Ltd.TokyoJapan
| | - Osamu Iwata
- RIKEN Baton Zone ProgramTsurumi‐ku, YokohamaJapan
- euglena Co., Ltd.TokyoJapan
| | - Kengo Suzuki
- RIKEN Baton Zone ProgramTsurumi‐ku, YokohamaJapan
- euglena Co., Ltd.TokyoJapan
| | - Keiichi Mochida
- RIKEN Center for Sustainable Resource ScienceTsurumi‐ku, YokohamaJapan
- RIKEN Baton Zone ProgramTsurumi‐ku, YokohamaJapan
- Kihara Institute for Biological ResearchYokohama City UniversityTotsuka‐ku, YokohamaJapan
- Graduate School of NanobioscienceYokohama City UniversityTsurumi‐ku, YokohamaJapan
- Institute of Plant Science and ResourcesOkayama UniversityKurashiki, OkayamaJapan
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19
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Toyama T, Hanaoka T, Yamada K, Suzuki K, Tanaka Y, Morikawa M, Mori K. Enhanced production of biomass and lipids by Euglena gracilis via co-culturing with a microalga growth-promoting bacterium, Emticicia sp. EG3. BIOTECHNOLOGY FOR BIOFUELS 2019; 12:205. [PMID: 31695747 PMCID: PMC6822413 DOI: 10.1186/s13068-019-1544-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Accepted: 08/17/2019] [Indexed: 05/03/2023]
Abstract
BACKGROUND Euglena gracilis, a unicellular flagellated microalga, is regarded as one of the most promising species as microalgal feedstock for biofuels. Its lipids (mainly wax esters) are suitable for biodiesel and jet fuel. Culture of E. gracilis using wastewater effluent will improve the economics of E. gracilis biofuel production. Enhancement of the productivity of E. gracilis biomass is critical to creating a highly efficient biofuels production system. Certain bacteria have been found to promote microalgal growth by creating a favorable microenvironment. These bacteria have been characterized as microalgae growth-promoting bacteria (MGPB). Co-culture of microalgae with MGPB might offer an effective strategy to enhance microalgal biomass production in wastewater effluent culture systems. However, no MGPB has been identified to enhance the growth of E. gracilis. The objectives of this study were, therefore, to isolate and characterize the MGPB effective for E. gracilis and to demonstrate that the isolated MGPB indeed enhances the production of biomass and lipids by E. gracilis in wastewater effluent culture system. RESULTS A bacterium, Emticicia sp. EG3, which is capable of promoting the growth of microalga E. gracilis, was isolated from an E. gracilis-municipal wastewater effluent culture. Biomass production rate of E. gracilis was enhanced 3.5-fold and 3.1-fold by EG3 in the co-culture system using a medium of heat-sterilized and non-sterilized wastewater effluent, respectively, compared to growth in the same effluent culture but without EG3. Two-step culture system was examined as follows: E. gracilis was cultured with or without EG3 in wastewater effluent in the first step and was further grown in wastewater effluent in the second step. Production yields of biomass and lipids by E. gracilis were enhanced 3.2-fold and 2.9-fold, respectively, in the second step of the system in which E. gracilis was co-cultured with EG3 in the first step. CONCLUSION Emticicia sp. EG3 is the first MGPB for E. gracilis. Growth-promoting bacteria such as EG3 will be promising agents for enhancing E. gracilis biomass/biofuel productivities.
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Affiliation(s)
- Tadashi Toyama
- Graduate Faculty of Interdisciplinary Research, University of Yamanashi, 4-3-11 Takeda, Kofu, Yamanashi 400-8511 Japan
| | - Tsubasa Hanaoka
- Integrated Graduate School of Medicine, Engineering, and Agricultural Sciences, University of Yamanashi, 4-3-11 Takeda, Kofu, Yamanashi 400-8511 Japan
| | - Koji Yamada
- Euglena Co., Ltd., 5-29-11 Shiba Minato-ku, Tokyo, 108-0014 Japan
- Microalgae Production Control Technology Laboratory, RIKEN, 1-7-22, Suehiro, Tsurumi, Yookohama, Kanagawa 230-0045 Japan
| | - Kengo Suzuki
- Euglena Co., Ltd., 5-29-11 Shiba Minato-ku, Tokyo, 108-0014 Japan
- Microalgae Production Control Technology Laboratory, RIKEN, 1-7-22, Suehiro, Tsurumi, Yookohama, Kanagawa 230-0045 Japan
| | - Yasuhiro Tanaka
- Graduate Faculty of Interdisciplinary Research, University of Yamanashi, 4-3-11 Takeda, Kofu, Yamanashi 400-8511 Japan
| | - Masaaki Morikawa
- Division of Biosphere Science, Graduate School of Environmental Science, Hokkaido University, Kita-10 Nishi-5, Kita-ku, Sapporo, 060-0810 Japan
| | - Kazuhiro Mori
- Graduate Faculty of Interdisciplinary Research, University of Yamanashi, 4-3-11 Takeda, Kofu, Yamanashi 400-8511 Japan
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Kim JY, Oh JJ, Jeon MS, Kim GH, Choi YE. Improvement of Euglena gracilis Paramylon Production through a Cocultivation Strategy with the Indole-3-Acetic Acid-Producing Bacterium Vibrio natriegens. Appl Environ Microbiol 2019; 85:e01548-19. [PMID: 31324633 PMCID: PMC6752030 DOI: 10.1128/aem.01548-19] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Accepted: 07/15/2019] [Indexed: 11/20/2022] Open
Abstract
We investigated the putative effects on the growth and paramylon production of Euglena gracilis of cocultivation with Vibrio natriegensE. gracilis heterotrophically cocultivated with V. natriegens displayed significant increases in biomass productivity and paramylon content. In addition, the effects of the bacterial inoculum density and the timing of inoculation on the growth of E. gracilis were examined, to determine the optimal conditions for cocultivation. With the optimal deployment of V. natriegens, biomass productivity and paramylon content were increased by more than 20% and 35%, respectively, compared to those in axenic E. gracilis cultures. Interestingly, indole-3-acetic acid biosynthesized by V. natriegens was responsible for these enhancements of E. gracilis The morphology of cocultured E. gracilis cells was assessed. Paramylon granules extracted from the cocultivation were significantly larger than those from axenic culture. Our study showed that screening for appropriate bacteria and subsequent cocultivation with E. gracilis represented an effective way to enhance biomass and metabolite production.IMPORTANCEEuglena gracilis has attracted special interest due to its ability to excessively accumulate paramylon. Paramylon is a linear β-1,3-glucan polysaccharide that is the principal polymer for energy storage in E. gracilis The polysaccharide features high bioactive functionality in the immune system. This study explored a new method to enhance the production of paramylon by E. gracilis, through cocultivation with the indole-3-acetic acid-producing bacterium Vibrio natriegens The enhanced production was achieved indirectly with the phytohormone-producing bacteria, instead of direct application of the hormone. The knowledge obtained in this study furthers the understanding of the effects of V. natriegens on the growth and physiology of E. gracilis.
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Affiliation(s)
- Jee Young Kim
- Division of Environmental Science and Ecological Engineering, Korea University, Seoul, South Korea
| | - Jeong-Joo Oh
- Division of Environmental Science and Ecological Engineering, Korea University, Seoul, South Korea
| | - Min Seo Jeon
- Division of Environmental Science and Ecological Engineering, Korea University, Seoul, South Korea
| | - Gyu-Hyeok Kim
- Division of Environmental Science and Ecological Engineering, Korea University, Seoul, South Korea
| | - Yoon-E Choi
- Division of Environmental Science and Ecological Engineering, Korea University, Seoul, South Korea
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Iwasaki K, Kaneko A, Tanaka Y, Ishikawa T, Noothalapati H, Yamamoto T. Visualizing wax ester fermentation in single Euglena gracilis cells by Raman microspectroscopy and multivariate curve resolution analysis. BIOTECHNOLOGY FOR BIOFUELS 2019; 12:128. [PMID: 31139258 PMCID: PMC6529988 DOI: 10.1186/s13068-019-1471-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Accepted: 05/16/2019] [Indexed: 06/09/2023]
Abstract
BACKGROUND Global demand for energy is on the rise at a time when limited natural resources are fast depleting. To address this issue, microalgal biofuels are being recommended as a renewable and eco-friendly substitute for fossil fuels. Euglena gracilis is one such candidate that has received special interest due to their ability to synthesize wax esters that serve as precursors for production of drop-in jet fuel. However, to realize economic viability and achieve industrial-scale production, development of novel methods to characterize algal cells, evaluate its culture conditions, and construct appropriate genetically modified strains is necessary. Here, we report a Raman microspectroscopy-based method to visualize important metabolites such as paramylon and ester during wax ester fermentation in single Euglena gracilis cells in a label-free manner. RESULTS We measured Raman spectra to obtain intracellular biomolecular information in Euglena under anaerobic condition. First, by univariate approach, we identified Raman markers corresponding to paramylon/esters and constructed their time-lapse chemical images. However, univariate analysis is severely limited in its ability to obtain detailed information as several molecules can contribute to a Raman band. Therefore, we further employed multivariate curve resolution analysis to obtain chain length-specific information and their abundance images of the produced esters. Accumulated esters in Euglena were particularly identified to be myristyl myristate (C28), a wax ester candidate suitable to prepare drop-in jet fuel. Interestingly, we found accumulation of two different forms of myristyl myristate for the first time in Euglena through our exploratory multivariate analysis. CONCLUSIONS We succeeded in visualizing molecular-specific information in Euglena during wax ester fermentation by Raman microspectroscopy. It is obvious from our results that simple univariate approach is insufficient and that multivariate curve resolution analysis is crucial to extract hidden information from Raman spectra. Even though we have not measured any mutants in this study, our approach is directly applicable to other systems and is expected to deepen the knowledge on lipid metabolism in microalgae, which eventually leads to new strategies that will help to enhance biofuel production efficiency in the future.
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Affiliation(s)
- Keita Iwasaki
- The United Graduate School of Agricultural Sciences, Tottori University, Tottori, 680-8550 Japan
| | - Asuka Kaneko
- Faculty of Life and Environmental Science, Shimane University, Matsue, 690-8504 Japan
| | - Yuji Tanaka
- Faculty of Life and Environmental Science, Shimane University, Matsue, 690-8504 Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Kawaguchi, 332-0012 Japan
| | - Takahiro Ishikawa
- Faculty of Life and Environmental Science, Shimane University, Matsue, 690-8504 Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Kawaguchi, 332-0012 Japan
| | - Hemanth Noothalapati
- Raman Project Center for Medical and Biological Applications, Shimane University, Matsue, 690-8504 Japan
| | - Tatsuyuki Yamamoto
- Faculty of Life and Environmental Science, Shimane University, Matsue, 690-8504 Japan
- Raman Project Center for Medical and Biological Applications, Shimane University, Matsue, 690-8504 Japan
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22
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Vesteg M, Hadariová L, Horváth A, Estraño CE, Schwartzbach SD, Krajčovič J. Comparative molecular cell biology of phototrophic euglenids and parasitic trypanosomatids sheds light on the ancestor of Euglenozoa. Biol Rev Camb Philos Soc 2019; 94:1701-1721. [PMID: 31095885 DOI: 10.1111/brv.12523] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Revised: 04/30/2019] [Accepted: 05/02/2019] [Indexed: 01/23/2023]
Abstract
Parasitic trypanosomatids and phototrophic euglenids are among the most extensively studied euglenozoans. The phototrophic euglenid lineage arose relatively recently through secondary endosymbiosis between a phagotrophic euglenid and a prasinophyte green alga that evolved into the euglenid secondary chloroplast. The parasitic trypanosomatids (i.e. Trypanosoma spp. and Leishmania spp.) and the freshwater phototrophic euglenids (i.e. Euglena gracilis) are the most evolutionary distant lineages in the Euglenozoa phylogenetic tree. The molecular and cell biological traits they share can thus be considered as ancestral traits originating in the common euglenozoan ancestor. These euglenozoan ancestral traits include common mitochondrial presequence motifs, respiratory chain complexes containing various unique subunits, a unique ATP synthase structure, the absence of mitochondria-encoded transfer RNAs (tRNAs), a nucleus with a centrally positioned nucleolus, closed mitosis without dissolution of the nuclear membrane and nucleoli, a nuclear genome containing the unusual 'J' base (β-D-glucosyl-hydroxymethyluracil), processing of nucleus-encoded precursor messenger RNAs (pre-mRNAs) via spliced-leader RNA (SL-RNA) trans-splicing, post-transcriptional gene silencing by the RNA interference (RNAi) pathway and the absence of transcriptional regulation of nuclear gene expression. Mitochondrial uridine insertion/deletion RNA editing directed by guide RNAs (gRNAs) evolved in the ancestor of the kinetoplastid lineage. The evolutionary origin of other molecular features known to be present only in either kinetoplastids (i.e. polycistronic transcripts, compaction of nuclear genomes) or euglenids (i.e. monocistronic transcripts, huge genomes, many nuclear cis-spliced introns, polyproteins) is unclear.
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Affiliation(s)
- Matej Vesteg
- Department of Biology and Ecology, Faculty of Natural Sciences, Matej Bel University, 974 01, Banská Bystrica, Slovakia
| | - Lucia Hadariová
- Biotechnology and Biomedicine Center of the Academy of Sciences and Charles University in Vestec (BIOCEV), 252 50, Vestec, Czech Republic.,Department of Parasitology, Faculty of Science, Charles University in Prague, 128 44, Prague, Czech Republic
| | - Anton Horváth
- Department of Biochemistry, Faculty of Natural Sciences, Comenius University, 842 15, Bratislava, Slovakia
| | - Carlos E Estraño
- Department of Biological Sciences, University of Memphis, Memphis, TN, 38152-3560, USA
| | - Steven D Schwartzbach
- Department of Biological Sciences, University of Memphis, Memphis, TN, 38152-3560, USA
| | - Juraj Krajčovič
- Department of Biology, Faculty of Natural Sciences, University of ss. Cyril and Methodius, 917 01, Trnava, Slovakia
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Gissibl A, Sun A, Care A, Nevalainen H, Sunna A. Bioproducts From Euglena gracilis: Synthesis and Applications. Front Bioeng Biotechnol 2019; 7:108. [PMID: 31157220 PMCID: PMC6530250 DOI: 10.3389/fbioe.2019.00108] [Citation(s) in RCA: 64] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2018] [Accepted: 04/29/2019] [Indexed: 11/24/2022] Open
Abstract
In recent years, the versatile phototrophic protist Euglena gracilis has emerged as an interesting candidate for application-driven research and commercialisation, as it is an excellent source of dietary protein, pro(vitamins), lipids, and the β-1,3-glucan paramylon only found in euglenoids. From these, paramylon is already marketed as an immunostimulatory agent in nutraceuticals. Bioproducts from E. gracilis can be produced under various cultivation conditions discussed in this review, and their yields are relatively high when compared with those achieved in microalgal systems. Future challenges include achieving the economy of large-scale cultivation. Recent insights into the complex metabolism of E. gracilis have highlighted unique metabolic pathways, which could provide new leads for product enhancement by genetic modification of the organism. Also, development of molecular tools for strain improvement are emerging rapidly, making E. gracilis a noteworthy challenger for microalgae such as Chlorella spp. and their products currently on the market.
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Affiliation(s)
- Alexander Gissibl
- Department of Molecular Sciences, Macquarie University, Sydney, NSW, Australia
- Australian Research Council Industrial Transformation Training Centre for Molecular Technology in the Food Industry, Sydney, NSW, Australia
| | - Angela Sun
- Department of Molecular Sciences, Macquarie University, Sydney, NSW, Australia
- Australian Research Council Industrial Transformation Training Centre for Molecular Technology in the Food Industry, Sydney, NSW, Australia
| | - Andrew Care
- Department of Molecular Sciences, Macquarie University, Sydney, NSW, Australia
| | - Helena Nevalainen
- Department of Molecular Sciences, Macquarie University, Sydney, NSW, Australia
- Australian Research Council Industrial Transformation Training Centre for Molecular Technology in the Food Industry, Sydney, NSW, Australia
- Biomolecular Discovery and Design Research Centre, Macquarie University, Sydney, NSW, Australia
| | - Anwar Sunna
- Department of Molecular Sciences, Macquarie University, Sydney, NSW, Australia
- Australian Research Council Industrial Transformation Training Centre for Molecular Technology in the Food Industry, Sydney, NSW, Australia
- Biomolecular Discovery and Design Research Centre, Macquarie University, Sydney, NSW, Australia
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24
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Tomiyama T, Goto K, Tanaka Y, Maruta T, Ogawa T, Sawa Y, Ito T, Ishikawa T. A major isoform of mitochondrial trans-2-enoyl-CoA reductase is dispensable for wax ester production in Euglena gracilis under anaerobic conditions. PLoS One 2019; 14:e0210755. [PMID: 30650145 PMCID: PMC6334954 DOI: 10.1371/journal.pone.0210755] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Accepted: 12/30/2018] [Indexed: 11/18/2022] Open
Abstract
Under anaerobic conditions, Euglena gracilis produces a large amount of wax ester through mitochondrial fatty acid synthesis from storage polysaccharides termed paramylon, to generate ATP. Trans-2-enoyl-CoA reductases (TERs) in mitochondria have been considered to play a key role in this process, because the enzymes catalyze the reduction of short chain length CoA-substrates (such as crotonyl-CoA). A TER enzyme (EgTER1) has been previously identified and enzymologically characterized; however, its physiological significance remained to be evaluated by genetic analysis. We herein generated EgTER1-knockdown Euglena cells, in which total crotonyl-CoA reductase activity was decreased to 10% of control value. Notably, the knockdown cells showed a severe bleaching phenotype with deficiencies in chlorophylls and glycolipids, but grew normally under heterotrophic conditions (with glucose supplementation). Moreover, the knockdown cells accumulated much greater quantities of wax ester than control cells before and after transfer to anaerobic conditions, which was accompanied by a large metabolomic change. Furthermore, we failed to find any contribution of other potential TER genes in wax ester production. Our findings propose a novel role of EgTER1 in the greening process and demonstrate that this enzyme is dispensable for wax ester production under anaerobic conditions.
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Affiliation(s)
- Takuya Tomiyama
- Department of Life Science and Biotechnology, Faculty of Life and Environmental Science, Shimane University, Matsue, Shimane, Japan
| | - Kyo Goto
- Department of Life Science and Biotechnology, Faculty of Life and Environmental Science, Shimane University, Matsue, Shimane, Japan
| | - Yuji Tanaka
- Department of Life Science and Biotechnology, Faculty of Life and Environmental Science, Shimane University, Matsue, Shimane, Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Chiyoda-ku, Tokyo, Japan
| | - Takanori Maruta
- Department of Life Science and Biotechnology, Faculty of Life and Environmental Science, Shimane University, Matsue, Shimane, Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Chiyoda-ku, Tokyo, Japan
| | - Takahisa Ogawa
- Department of Life Science and Biotechnology, Faculty of Life and Environmental Science, Shimane University, Matsue, Shimane, Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Chiyoda-ku, Tokyo, Japan
| | - Yoshihiro Sawa
- Department of Life Science and Biotechnology, Faculty of Life and Environmental Science, Shimane University, Matsue, Shimane, Japan
| | - Takuro Ito
- Institute for Advanced Biosciences, Keio University, Tsuruoka, Yamagata, Japan
- Systems Biology Program, Graduate School of Media and Governance, Keio University, Fujisawa, Japan
| | - Takahiro Ishikawa
- Department of Life Science and Biotechnology, Faculty of Life and Environmental Science, Shimane University, Matsue, Shimane, Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Chiyoda-ku, Tokyo, Japan
- * E-mail:
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25
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Tomita Y, Takeya M, Suzuki K, Nitta N, Higuchi C, Marukawa-Hashimoto Y, Osanai T. Amino acid excretion from Euglena gracilis cells in dark and anaerobic conditions. ALGAL RES 2019. [DOI: 10.1016/j.algal.2018.11.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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26
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Nakazawa M, Ando H, Nishimoto A, Ohta T, Sakamoto K, Ishikawa T, Ueda M, Sakamoto T, Nakano Y, Miyatake K, Inui H. Anaerobic respiration coupled with mitochondrial fatty acid synthesis in wax ester fermentation by Euglena gracilis. FEBS Lett 2018; 592:4020-4027. [PMID: 30328102 PMCID: PMC6587861 DOI: 10.1002/1873-3468.13276] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Revised: 10/09/2018] [Accepted: 10/12/2018] [Indexed: 11/08/2022]
Abstract
In Euglena gracilis, wax ester fermentation produces ATP during anaerobiosis. Here, we report that anaerobic wax ester production is suppressed when the mitochondrial electron transport chain complex I is inhibited by rotenone, whereas it is increased by the uncoupler carbonyl cyanide m-chlorophenylhydrazone (CCCP). The ADP/ATP ratio in anaerobic cells is elevated by treatment with either rotenone or CCCP. Gene silencing experiments indicate that acyl-CoA dehydrogenase, electron transfer flavoprotein (ETF), and rhodoquinone (RQ) participate in wax ester production. These results suggest that fatty acids are synthesized in mitochondria by the reversal of β-oxidation, where trans-2-enoyl-CoA is reduced mainly by acyl-CoA dehydrogenase using the electrons provided by NADH via the electron transport chain complex I, RQ, and ETF, and that ATP production is highly supported by anaerobic respiration utilizing trans-2-enoyl-CoA as a terminal electron acceptor.
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Affiliation(s)
- Masami Nakazawa
- Division of Applied Life SciencesGraduate School of Life and Environmental SciencesOsaka Prefecture UniversitySakaiJapan
- Core Research for Evolutional Science and Technology (CREST)Japan Science and Technology Agency (JST)KawaguchiJapan
| | - Hiroko Ando
- Division of Applied Life SciencesGraduate School of Life and Environmental SciencesOsaka Prefecture UniversitySakaiJapan
| | - Ayusa Nishimoto
- Division of Applied Life SciencesGraduate School of Life and Environmental SciencesOsaka Prefecture UniversitySakaiJapan
| | - Tsuyoshi Ohta
- Division of Applied Life SciencesGraduate School of Life and Environmental SciencesOsaka Prefecture UniversitySakaiJapan
| | - Kimitoshi Sakamoto
- Department of Biochemistry and Molecular BiologyFaculty of Agriculture and Life ScienceHirosaki UniversityHirosakiJapan
| | - Takahiro Ishikawa
- Core Research for Evolutional Science and Technology (CREST)Japan Science and Technology Agency (JST)KawaguchiJapan
- Department of Life Science and BiotechnologyFaculty of Life and Environmental ScienceShimane UniversityMatsueJapan
| | - Mitsuhiro Ueda
- Division of Applied Life SciencesGraduate School of Life and Environmental SciencesOsaka Prefecture UniversitySakaiJapan
| | - Tatsuji Sakamoto
- Division of Applied Life SciencesGraduate School of Life and Environmental SciencesOsaka Prefecture UniversitySakaiJapan
| | - Yoshihisa Nakano
- Division of Applied Life SciencesGraduate School of Life and Environmental SciencesOsaka Prefecture UniversitySakaiJapan
| | - Kazutaka Miyatake
- Department of Nutrition and Food SciencesFaculty of Human and Cultural StudiesTezukayama Gakuin UniversitySakaiJapan
| | - Hiroshi Inui
- Core Research for Evolutional Science and Technology (CREST)Japan Science and Technology Agency (JST)KawaguchiJapan
- Department of NutritionCollege of Health and Human SciencesOsaka Prefecture UniversityHabikinoJapan
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27
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Feng Y, Kitaoku Y, Tanaka J, Taira T, Ohnuma T, Aachmann FL, Fukamizo T. Mode of action and specificity of a chitinase from unicellular microalgae, Euglena gracilis. PLANT MOLECULAR BIOLOGY 2018; 97:553-564. [PMID: 30083952 DOI: 10.1007/s11103-018-0759-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Accepted: 07/26/2018] [Indexed: 06/08/2023]
Abstract
Euglena gracilis is a unicellular microalga showing characteristics of both plants and animals, and extensively used as a model organism in the research works of biochemistry and molecular biology. Biotechnological applications of E. gracilis have been conducted for production of numerous important compounds. However, chitin-mediated defense system intensively studied in higher plants remains to be investigated in this microalga. Recently, Taira et al. (Biosci Biotechnol Biochem 82:1090-1100, 2018) isolated a unique chitinase gene, comprising two catalytic domains almost homologous to each other (Cat1 and Cat2) and two chitin-binding domains (CBD1 and CBD2), from E. gracilis. We herein examined the mode of action and the specificity of the recombinant Cat2 by size exclusion chromatography and NMR spectroscopy. Both Cat1 and Cat2 appeared to act toward chitin substrate with non-processive/endo-splitting mode, recognizing two contiguous N-acetylglucosamine units at subsites - 2 and - 1. This is the first report on a chitinase having two endo-splitting catalytic domains. A cooperative action of two different endo-splitting domains may be advantageous for defensive action of the E. gracilis chitinase. The unicellular alga, E. gracilis, produces a chitinase consisting of two GH18 catalytic domains (Cat1 and Cat2) and two CBM18 chitin-binding domains (CBD1 and CBD2). Here, we produced a recombinant protein of the Cat2 domain to examine its mode of action as well as specificity. Cat2 hydrolyzed N-acetylglucosamine (A) oligomers (An, n = 4, 5, and 6) and partially N-acetylated chitosans with a non-processive/endo-splitting mode of action. NMR analysis of the product mixture from the enzymatic digestion of chitosan revealed that the reducing ends were exclusively A-unit, and the nearest neighbors of the reducing ends were mostly A-unit but not exclusively. Both A-unit and D-unit were found at the non-reducing ends and the nearest neighbors. These results indicated strong and absolute specificities for subsites - 2 and - 1, respectively, and no preference for A-unit at subsites + 1 and + 2. The same results were obtained from sugar sequence analysis of the individual enzymatic products from the chitosans. The subsite specificities of Cat2 are similar to those of GH18 human chitotriosidase, but differ from those of plant GH18 chitinases. Since the structures of Cat1 and Cat2 resemble to each other (99% similarity in amino acid sequences), Cat1 may hydrolyze the substrate with the same mode of action. Thus, the E. gracilis chitinase appears to act toward chitin polysaccharide chain through a cooperative action of the two endo-splitting catalytic domains, recognizing two contiguous A-units at subsites - 2 and - 1.
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Affiliation(s)
- Yiming Feng
- Norwegian Biopolymer Laboratory (NOBIPOL), Department of Biotechnology and Food Science, NTNU Norwegian University of Science and Technology, 7491, Trondheim, Norway
| | - Yoshihito Kitaoku
- Department of Advanced Bioscience, Kindai University, 3327-204 Nakamachi, Nara, 631-8505, Japan
| | - Jun Tanaka
- Department of Advanced Bioscience, Kindai University, 3327-204 Nakamachi, Nara, 631-8505, Japan
| | - Toki Taira
- Department of Bioscience and Biotechnology, University of the Ryukyus, Nishihara-cho, 903-0213, Japan
| | - Takayuki Ohnuma
- Department of Advanced Bioscience, Kindai University, 3327-204 Nakamachi, Nara, 631-8505, Japan
| | - Finn L Aachmann
- Norwegian Biopolymer Laboratory (NOBIPOL), Department of Biotechnology and Food Science, NTNU Norwegian University of Science and Technology, 7491, Trondheim, Norway
| | - Tamo Fukamizo
- Department of Advanced Bioscience, Kindai University, 3327-204 Nakamachi, Nara, 631-8505, Japan.
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Maeno T, Uzawa T, Kono I, Okano K, Iino T, Fukita K, Oshikawa Y, Ogawa T, Iwata O, Ito T, Suzuki K, Goda K, Hosokawa Y. Targeted delivery of fluorogenic peptide aptamers into live microalgae by femtosecond laser photoporation at single-cell resolution. Sci Rep 2018; 8:8271. [PMID: 29844463 PMCID: PMC5974127 DOI: 10.1038/s41598-018-26565-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2018] [Accepted: 05/09/2018] [Indexed: 02/01/2023] Open
Abstract
Microalgae-based metabolic engineering has been proven effective for producing valuable substances such as food supplements, pharmaceutical drugs, biodegradable plastics, and biofuels in the past decade. The ability to accurately visualize and quantify intracellular metabolites in live microalgae is essential for efficient metabolic engineering, but remains a major challenge due to the lack of characterization methods. Here we demonstrate it by synthesizing fluorogenic peptide aptamers with specific binding affinity to a target metabolite and delivering them into live microalgae by femtosecond laser photoporation at single-cell resolution. As a proof-of-principle demonstration of our method, we use it to characterize Euglena gracilis, a photosynthetic unicellular motile microalgal species, which is capable of producing paramylon (a carbohydrate granule similar to starch). Specifically, we synthesize a peptide aptamer containing a paramylon-binding fluorescent probe, 7-nitrobenzofurazan, and introduce it into E. gracilis cells one-by-one by suppressing their mobility with mannitol and transiently perforating them with femtosecond laser pulses at 800 nm for photoporation. To demonstrate the method’s practical utility in metabolic engineering, we perform spatially and temporally resolved fluorescence microscopy of single live photoporated E. gracilis cells under different culture conditions. Our method holds great promise for highly efficient microalgae-based metabolic engineering.
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Affiliation(s)
- Takanori Maeno
- Graduate School of Materials Science, Nara Institute of Science and Technology, Ikoma, 630-0192, Japan
| | - Takanori Uzawa
- Nano Medical Engineering Laboratory, RIKEN, Wako, 351-0198, Japan. .,RIKEN Center for Emergent Matter Science, Wako, 351-1098, Japan.
| | - Izumi Kono
- RIKEN Center for Emergent Matter Science, Wako, 351-1098, Japan
| | - Kazunori Okano
- Graduate School of Materials Science, Nara Institute of Science and Technology, Ikoma, 630-0192, Japan
| | - Takanori Iino
- Graduate School of Materials Science, Nara Institute of Science and Technology, Ikoma, 630-0192, Japan
| | - Keisuke Fukita
- Graduate School of Materials Science, Nara Institute of Science and Technology, Ikoma, 630-0192, Japan
| | - Yuki Oshikawa
- Graduate School of Materials Science, Nara Institute of Science and Technology, Ikoma, 630-0192, Japan
| | - Taro Ogawa
- euglena Co., Ltd, Yokohama, 230-0046, Japan
| | | | - Takuro Ito
- Japan Science and Technology Agency, Kawaguchi, 332-0012, Japan
| | | | - Keisuke Goda
- Japan Science and Technology Agency, Kawaguchi, 332-0012, Japan. .,Department of Chemistry, University of Tokyo, Tokyo, 113-0033, Japan.
| | - Yoichiroh Hosokawa
- Graduate School of Materials Science, Nara Institute of Science and Technology, Ikoma, 630-0192, Japan.
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Wang Y, Seppänen-Laakso T, Rischer H, Wiebe MG. Euglena gracilis growth and cell composition under different temperature, light and trophic conditions. PLoS One 2018; 13:e0195329. [PMID: 29649233 PMCID: PMC5896972 DOI: 10.1371/journal.pone.0195329] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2017] [Accepted: 03/20/2018] [Indexed: 12/12/2022] Open
Abstract
Background Euglena gracilis, a photosynthetic protist, produces protein, unsaturated fatty acids, wax esters, and a unique β-1,3-glucan called paramylon, along with other valuable compounds. The cell composition of E. gracilis was investigated in this study to understand how light and organic carbon (photo-, mixo- and heterotrophic conditions) affected growth and cell composition (especially lipids). Comparisons were primarily carried out in cultures grown at 23 °C, but the effect of growth at higher temperatures (27 or 30 °C) was also considered. Cell growth Specific growth rates were slightly lower when E. gracilis was grown on glucose in either heterotrophic or mixotrophic conditions than when grown photoautotrophically, although the duration of exponential growth was longer. Temperature determined the rate of exponential growth in all cultures, but not the linear growth rate during light-limited growth in phototrophic conditions. Temperature had less effect on cell composition. Cell composition Although E. gracilis was not expected to store large amounts of paramylon when grown phototrophically, we observed that phototrophic cells could contain up to 50% paramylon. These cells contained up to 33% protein and less than 20% lipophilic compounds, as expected. The biomass contained about 8% fatty acids (measured as fatty acid methyl esters), most of which were unsaturated. The fatty acid content of cells grown in mixotrophic conditions was similar to that observed in phototrophic cells, but was lower in cells grown heterotrophically. Heterotrophic cells contained less unsaturated fatty acids than phototrophic or mixotrophic cells. α-Linolenic acid was present at 5 to 18 mg g-1 dry biomass in cells grown in the presence of light, but at < 0.5 mg g-1 biomass in cells grown in the dark. Eicosapentaenoic and docosahexaenoic acids were detected at 1 to 5 mg g-1 biomass. Light was also important for the production of vitamin E and phytol.
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Affiliation(s)
- Yanming Wang
- VTT Technical Research Centre of Finland Ltd., Espoo, Finland
| | | | - Heiko Rischer
- VTT Technical Research Centre of Finland Ltd., Espoo, Finland
| | - Marilyn G. Wiebe
- VTT Technical Research Centre of Finland Ltd., Espoo, Finland
- * E-mail:
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Shibata S, Arimura SI, Ishikawa T, Awai K. Alterations of Membrane Lipid Content Correlated With Chloroplast and Mitochondria Development in Euglena gracilis. FRONTIERS IN PLANT SCIENCE 2018; 9:370. [PMID: 29636759 PMCID: PMC5881160 DOI: 10.3389/fpls.2018.00370] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Accepted: 03/06/2018] [Indexed: 05/13/2023]
Abstract
Euglenoids are unique protists that can grow photoautotrophically, photomixotrophically, and heterotrophically. Here we grew Euglena gracilis under these different growth conditions and determined cellular contents of seven membrane lipids and one storage lipid (triacylglycerol), which account for more than 94 mol% of total membrane lipids. We also describe the relationship among chloroplast and mitochondria developments with lipid contents, protein contents, and oxygen evolution/consumption rates. In photoautotrophic growth conditions, E. gracilis cells accumulated chlorophyll, photosynthetic proteins, and glycolipids typical to thylakoid membranes. The same occurred for the cells grown under photomixotrophic conditions with higher respiration rates. In heterotrophic conditions, E. gracilis cells had higher respiration rates compared to cells grown in other conditions with the accumulation of pyruvate: NADP+ oxidoreductase, a mitochondrial protein and phospholipid common in mitochondria. Cells were also observed using a confocal laser scanning microscope and found to show more chlorophyll autofluorescence when grown photoautotrophically and photomixotrophycally, and fluorescence of MitoTracker when grown photomixotrophically and heterotrophically. These results suggest that under illumination, E. gracilis develops functional thylakoid membranes with membrane lipids and proteins for photosynthesis. In the medium with glucose, the cells develop mitochondria with phospholipids and proteins for respiration. Possible application based on lipid analysis for the enhancement of wax ester or alkene synthesis is discussed.
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Affiliation(s)
- Shiori Shibata
- Graduate School of Integrated Science and Technology, Shizuoka University, Shizuoka, Japan
| | - Shin-ichi Arimura
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
- Precursory Research for Embryonic Science and Technology, Japan Science and Technology Agency, Saitama, Japan
| | - Takahiro Ishikawa
- Department of Life Science and Biotechnology, Faculty of Life and Environmental Science, Shimane University, Matsue, Japan
- Core Research for Evolutional Science and Technology, Japan Science and Technology Agency, Tokyo, Japan
| | - Koichiro Awai
- Graduate School of Integrated Science and Technology, Shizuoka University, Shizuoka, Japan
- Core Research for Evolutional Science and Technology, Japan Science and Technology Agency, Tokyo, Japan
- Research Institute of Electronics, Shizuoka University, Hamamatsu, Japan
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31
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Tomiyama T, Kurihara K, Ogawa T, Maruta T, Ogawa T, Ohta D, Sawa Y, Ishikawa T. Wax Ester Synthase/Diacylglycerol Acyltransferase Isoenzymes Play a Pivotal Role in Wax Ester Biosynthesis in Euglena gracilis. Sci Rep 2017; 7:13504. [PMID: 29044218 PMCID: PMC5647427 DOI: 10.1038/s41598-017-14077-6] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Accepted: 10/06/2017] [Indexed: 11/08/2022] Open
Abstract
Wax ester fermentation is a unique energy gaining pathway for a unicellular phytoflagellated protozoan, Euglena gracilis, to survive under anaerobiosis. Wax esters produced in E. gracilis are composed of saturated fatty acids and alcohols, which are the major constituents of myristic acid and myristyl alcohol. Thus, wax esters can be promising alternative biofuels. Here, we report the identification and characterization of wax ester synthase/diacylglycerol acyltrasferase (WSD) isoenzymes as the terminal enzymes of wax ester production in E. gracilis. Among six possible Euglena WSD orthologs predicted by BLASTX search, gene expression analysis and in vivo evaluation for enzyme activity with yeast expressing individual recombinant WSDs indicated that two of them (EgWSD2 and EgWSD5) predominantly function as wax ester synthase. Furthermore, experiments with gene silencing demonstrated a pivotal role of both EgWSD2 and EgWSD5 in wax ester synthesis, as evidenced by remarkably reduced wax ester contents in EgWSD2/5-double knockdown E. gracilis cells treated with anaerobic conditions. Interestingly, the decreased ability to produce wax ester did not affect adaptation of E. gracilis to anaerobiosis. Lipid profile analysis suggested allocation of metabolites to other compounds including triacylglycerol instead of wax esters.
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Affiliation(s)
- Takuya Tomiyama
- Department of Life Science and Biotechnology, Faculty of Life and Environmental Science, Shimane University, 1060 Nishikawatsu, Matsue, Shimane, 690-8504, Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Chiyoda-ku, Tokyo, 102-0076, Japan
| | - Kaeko Kurihara
- Department of Life Science and Biotechnology, Faculty of Life and Environmental Science, Shimane University, 1060 Nishikawatsu, Matsue, Shimane, 690-8504, Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Chiyoda-ku, Tokyo, 102-0076, Japan
| | - Takahisa Ogawa
- Department of Life Science and Biotechnology, Faculty of Life and Environmental Science, Shimane University, 1060 Nishikawatsu, Matsue, Shimane, 690-8504, Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Chiyoda-ku, Tokyo, 102-0076, Japan
| | - Takanori Maruta
- Department of Life Science and Biotechnology, Faculty of Life and Environmental Science, Shimane University, 1060 Nishikawatsu, Matsue, Shimane, 690-8504, Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Chiyoda-ku, Tokyo, 102-0076, Japan
| | - Takumi Ogawa
- Graduate School of Life and Environmental Sciences, Osaka Prefecture University, 1-1 Gakuen-chou, Nakaku, Sakai, Osaka, 599-8531, Japan
| | - Daisaku Ohta
- Graduate School of Life and Environmental Sciences, Osaka Prefecture University, 1-1 Gakuen-chou, Nakaku, Sakai, Osaka, 599-8531, Japan
| | - Yoshihiro Sawa
- Department of Life Science and Biotechnology, Faculty of Life and Environmental Science, Shimane University, 1060 Nishikawatsu, Matsue, Shimane, 690-8504, Japan
| | - Takahiro Ishikawa
- Department of Life Science and Biotechnology, Faculty of Life and Environmental Science, Shimane University, 1060 Nishikawatsu, Matsue, Shimane, 690-8504, Japan.
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Chiyoda-ku, Tokyo, 102-0076, Japan.
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