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Tsai TY, Chien YL, Zheng YY, Li YC, Chen JC, Su RC, Ben-Sheleg A, Khozin-Goldberg I, Vonshak A, Lee TM. Modification in the ascorbate-glutathione cycle leads to a better acclimation to high light in the rose Bengal resistant mutant of Nannochloropsis oceanica. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2024; 207:108326. [PMID: 38237421 DOI: 10.1016/j.plaphy.2023.108326] [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: 08/08/2023] [Revised: 12/27/2023] [Accepted: 12/28/2023] [Indexed: 03/16/2024]
Abstract
Understanding how to adapt outdoor cultures of Nannochloropsis oceanica to high light (HL) is vital for boosting productivity. The N. oceanica RB2 mutant, obtained via ethyl methanesulfonate mutagenesis, was chosen for its tolerance to Rose Bengal (RB), a singlet oxygen (1O2) generator. Compared to the wild type (WT), the RB2 mutant showed higher resilience to excess light conditions. Analyzing the ascorbate-glutathione cycle (AGC), involving ascorbate peroxidases (APX, EC 1.11.1.11), dehydroascorbate reductase (DHAR, EC 1.8.5.1), and glutathione reductase (GR, EC 1.8.1.7), in the RB2 mutant under HL stress provided valuable insights. At 250 μmol photon m-2 s-1 (HL), the WT strain displayed superoxide anion radicals (O2▪-) and hydrogen peroxide (H2O2) accumulation, increased lipid peroxidation, and cell death compared to normal light (NL) conditions (50 μmol photon m-2 s-1). The RB2 mutant didn't accumulate O2▪- and H2O2 after HL exposure, and exhibited increased APX, DHAR, and GR activities and transcript levels compared to WT and remained consistent after HL treatment. Although the RB2 mutant had a smaller ascorbate (AsA) pool than the WT, its ability to regenerate dehydroascorbate (DHA) increased post HL exposure, indicated by a higher AsA/DHA ratio. Additionally, under HL conditions, the RB2 mutant displayed an improved glutathione (GSH) regeneration rate (GSH/GSSG ratio) without changing the GSH pool size. Remarkably, H2O2 or menadione (a O2▪- donor) treatment induced cell death in the WT strain but not in the RB2 mutant. These findings emphasize the essential role of AGC in the RB2 mutant of Nannochloropsis in handling photo-oxidative stress.
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Affiliation(s)
- Tsung-Yu Tsai
- Department of Marine Biotechnology and Resources, National Sun Yat-sen University, Kaohsiung 804, Taiwan
| | - Yi-Lin Chien
- Department of Marine Biotechnology and Resources, National Sun Yat-sen University, Kaohsiung 804, Taiwan
| | - Yu-Yun Zheng
- Department of Marine Biotechnology and Resources, National Sun Yat-sen University, Kaohsiung 804, Taiwan
| | - Yu-Chia Li
- Department of Marine Biotechnology and Resources, National Sun Yat-sen University, Kaohsiung 804, Taiwan
| | - Jen-Chih Chen
- Institute of Biotechnology, National Taiwan University, Taipei 106, Taiwan
| | - Ruey-Chih Su
- Department of Life Science, Fu-Jen University, New Taipei City 242, Taiwan
| | - Avraham Ben-Sheleg
- Microalgal Biotechnology Laboratory, The French Associates Institute for Agriculture and Biotechnology of Drylands, Jacob Blaustein Institute for Desert Research, Ben-Gurion University of the Negev, Sede-Boqer Campus, Midreshet Ben-Gurion 8499000, Israel
| | - Inna Khozin-Goldberg
- Microalgal Biotechnology Laboratory, The French Associates Institute for Agriculture and Biotechnology of Drylands, Jacob Blaustein Institute for Desert Research, Ben-Gurion University of the Negev, Sede-Boqer Campus, Midreshet Ben-Gurion 8499000, Israel.
| | - Avigad Vonshak
- Microalgal Biotechnology Laboratory, The French Associates Institute for Agriculture and Biotechnology of Drylands, Jacob Blaustein Institute for Desert Research, Ben-Gurion University of the Negev, Sede-Boqer Campus, Midreshet Ben-Gurion 8499000, Israel.
| | - Tse-Min Lee
- Department of Marine Biotechnology and Resources, National Sun Yat-sen University, Kaohsiung 804, Taiwan; Institute of Biotechnology, National Taiwan University, Taipei 106, Taiwan; Doctoral Degree Program in Marine Biotechnology, National Sun Yat-sen University, Kaohsiung 804, Taiwan.
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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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Tamaki S, Sato R, Koshitsuka Y, Asahina M, Kodama Y, Ishikawa T, Shinomura T. Suppression of the Lycopene Cyclase Gene Causes Downregulation of Ascorbate Peroxidase Activity and Decreased Glutathione Pool Size, Leading to H 2O 2 Accumulation in Euglena gracilis. FRONTIERS IN PLANT SCIENCE 2021; 12:786208. [PMID: 34925426 PMCID: PMC8678482 DOI: 10.3389/fpls.2021.786208] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Accepted: 11/11/2021] [Indexed: 06/02/2023]
Abstract
Carotenoids are photosynthetic pigments and hydrophobic antioxidants that are necessary for the survival of photosynthetic organisms, including the microalga Euglena gracilis. In the present study, we identified an uncharacterized gene encoding the E. gracilis β-carotene synthetic enzyme lycopene cyclase (EgLCY) and discovered a relationship between EgLCY-mediated carotenoid synthesis and the reactive oxygen species (ROS) scavenging system ascorbate-glutathione cycle. The EgLCY cDNA sequence was obtained via homology searching E. gracilis transcriptome data. An enzyme assay using Escherichia coli demonstrated that EgLCY converts lycopene to β-carotene. E. gracilis treated with EgLCY double-stranded RNA (dsRNA) produced colorless cells with hypertrophic appearance, inhibited growth, and marked decrease in carotenoid and chlorophyll content, suggesting that EgLCY is essential for the synthesis of β-carotene and downstream carotenoids, which are abundant and physiologically functional. In EgLCY dsRNA-treated cells, the ascorbate-glutathione cycle, composed of ascorbate peroxidase (APX), dehydroascorbate reductase (DHAR), monodehydroascorbate reductase (MDAR), and glutathione reductase (GR), was unusually modulated; APX and GR activities significantly decreased, whereas DHAR and MDAR activities increased. Ascorbate content was significantly increased and glutathione content significantly decreased in EgLCY dsRNA-treated cells and was correlated with their recycling enzyme activities. Fluorescent imaging demonstrated that EgLCY dsRNA-treated cells accumulated higher levels of H2O2 compared to wild-type cells. Taken together, this study revealed that EgLCY-mediated synthesis of β-carotene and downstream carotenoid species upregulates APX activity and increases glutathione pool size for H2O2 scavenging. Our study suggests a possible relationship between carotenoid synthesis and the ascorbate-glutathione cycle for ROS scavenging in E. gracilis.
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Affiliation(s)
- Shun Tamaki
- Department of Biosciences, School of Science and Engineering, Teikyo University, Tochigi, Japan
| | - Ryosuke Sato
- Department of Biosciences, School of Science and Engineering, Teikyo University, Tochigi, Japan
| | - Yuki Koshitsuka
- Department of Biosciences, School of Science and Engineering, Teikyo University, Tochigi, Japan
| | - Masashi Asahina
- Department of Biosciences, School of Science and Engineering, Teikyo University, Tochigi, Japan
- Advanced Instrumental Analysis Center, Teikyo University, Tochigi, Japan
| | - Yutaka Kodama
- Center for Bioscience Research and Education, Utsunomiya University, Tochigi, Japan
| | - Takahiro Ishikawa
- Institute of Agricultural and Life Sciences, Academic Assembly, Shimane University, Matsue, Japan
| | - Tomoko Shinomura
- Department of Biosciences, School of Science and Engineering, Teikyo University, Tochigi, Japan
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Liang S, Gan C, Dai Y, Zhang C, Bai X, Zhang S, Wheeler AR, Chen H, Feng L. Interaction between positive and negative dielectric microparticles/microorganism in optoelectronic tweezers. LAB ON A CHIP 2021; 21:4379-4389. [PMID: 34596652 DOI: 10.1039/d1lc00610j] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Optoelectronic tweezers (OET) is a noncontact micromanipulation technology for controlling microparticles and cells. In the OET, it is necessary to configure a medium with different electrical properties to manipulate different particles and to avoid the interaction between two particles. Here, a new method exploiting the interaction between different dielectric properties of micro-objects to achieve the trapping, transport, and release of particles in the OET system was proposed. Besides, the effect of interaction between the micro-objects with positive and negative dielectric properties was simulated by the arbitrary Lagrangian-Eulerian (ALE) method. In addition, compared with conventional OET systems relying on fabrication processes involving the assembly of photoelectric materials, a contactless OET platform with an iPad-based wireless-control interface was established to achieve convenient control. Finally, this platform was used in the interaction of swimming microorganisms (positive-dielectric properties) with microparticles (negative-dielectric properties) at different scales. It showed that one particle could interact with 5 particles simultaneously, indicating that the interaction can be applied to enhance the high-throughput transportation capacities of the OET system and assemble some special microstructures. Owing to the low power, microorganisms were free from adverse influence during the experiment. In the future, the interaction of particles in a simple OET platform is a promising alternative in micro-nano manipulation for controlling drug release from uncontaminated cells in targeted therapy research.
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Affiliation(s)
- Shuzhang Liang
- School of Mechanical Engineering & Automation, Beihang University, Beijing, 100191, China.
| | - Chunyuan Gan
- School of Mechanical Engineering & Automation, Beihang University, Beijing, 100191, China.
| | - Yuguo Dai
- School of Mechanical Engineering & Automation, Beihang University, Beijing, 100191, China.
| | - Chaonan Zhang
- School of Mechanical Engineering & Automation, Beihang University, Beijing, 100191, China.
| | - Xue Bai
- School of Mechanical Engineering & Automation, Beihang University, Beijing, 100191, China.
| | - Shuailong Zhang
- School of Mechatronical Engineering, Beijing Institute of Technology, Beijing, 100081, China
- Beijing Advanced Innovation Center for Intelligent Robots and Systems, Beijing Institute of Technology, Beijing, 100081, China
| | - Aaron R Wheeler
- Department of Chemistry, University of Toronto, 80 St George St., Toronto, ON, M5S 3H6, Canada
- Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, 160 College St, Toronto, ON, M5S 3E1, Canada
- Institute for Biomaterials and Biomedical Engineering, University of Toronto, 164 College St, Toronto, ON, M5S 3G9, Canada
| | - Huawei Chen
- School of Mechanical Engineering & Automation, Beihang University, Beijing, 100191, China.
- Beijing Advanced Innovation Center for Biomedical Engineering, Beihang University, Beijing, 100191, China
| | - Lin Feng
- School of Mechanical Engineering & Automation, Beihang University, Beijing, 100191, China.
- Beijing Advanced Innovation Center for Biomedical Engineering, Beihang University, Beijing, 100191, China
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Tamaki S, Mochida K, Suzuki K. Diverse Biosynthetic Pathways and Protective Functions against Environmental Stress of Antioxidants in Microalgae. PLANTS (BASEL, SWITZERLAND) 2021; 10:1250. [PMID: 34205386 PMCID: PMC8234872 DOI: 10.3390/plants10061250] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Revised: 06/14/2021] [Accepted: 06/15/2021] [Indexed: 01/08/2023]
Abstract
Eukaryotic microalgae have been classified into several biological divisions and have evolutionarily acquired diverse morphologies, metabolisms, and life cycles. They are naturally exposed to environmental stresses that cause oxidative damage due to reactive oxygen species accumulation. To cope with environmental stresses, microalgae contain various antioxidants, including carotenoids, ascorbate (AsA), and glutathione (GSH). Carotenoids are hydrophobic pigments required for light harvesting, photoprotection, and phototaxis. AsA constitutes the AsA-GSH cycle together with GSH and is responsible for photooxidative stress defense. GSH contributes not only to ROS scavenging, but also to heavy metal detoxification and thiol-based redox regulation. The evolutionary diversity of microalgae influences the composition and biosynthetic pathways of these antioxidants. For example, α-carotene and its derivatives are specific to Chlorophyta, whereas diadinoxanthin and fucoxanthin are found in Heterokontophyta, Haptophyta, and Dinophyta. It has been suggested that AsA is biosynthesized via the plant pathway in Chlorophyta and Rhodophyta and via the Euglena pathway in Euglenophyta, Heterokontophyta, and Haptophyta. The GSH biosynthetic pathway is conserved in all biological kingdoms; however, Euglenophyta are able to synthesize an additional thiol antioxidant, trypanothione, using GSH as the substrate. In the present study, we reviewed and discussed the diversity of microalgal antioxidants, including recent findings.
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Affiliation(s)
- Shun Tamaki
- Microalgae Production Control Technology Laboratory, RIKEN Baton Zone Program, Yokohama 230-0045, Japan; (K.M.); (K.S.)
| | - Keiichi Mochida
- Microalgae Production Control Technology Laboratory, RIKEN Baton Zone Program, Yokohama 230-0045, Japan; (K.M.); (K.S.)
- RIKEN Center for Sustainable Resource Science, Yokohama 230-0045, Japan
- Kihara Institute for Biological Research, Yokohama City University, Yokohama 230-0045, Japan
- School of Information and Data Sciences, Nagasaki University, Nagasaki 852-8521, Japan
| | - Kengo Suzuki
- Microalgae Production Control Technology Laboratory, RIKEN Baton Zone Program, Yokohama 230-0045, Japan; (K.M.); (K.S.)
- euglena Co., Ltd., Tokyo 108-0014, Japan
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Hybrid Heme Peroxidases from Rice Blast Fungus Magnaporthe oryzae Involved in Defence against Oxidative Stress. Antioxidants (Basel) 2020; 9:antiox9080655. [PMID: 32718101 PMCID: PMC7463560 DOI: 10.3390/antiox9080655] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Revised: 07/21/2020] [Accepted: 07/22/2020] [Indexed: 11/17/2022] Open
Abstract
Hybrid B heme peroxidases are recently discovered unique oxidoreductases present solely in the fungal kingdom. We have investigated two typical representatives from Magnaporthe oryzae—one of the most dangerous phytopathogens known as a causal agent of the rice blast disease. First, we focused on native expression of two detected hyBpox paralogs by the means of reverse-transcription quantitative real-time PCR. Our results indicate a 7-fold induction of the MohyBpox1 transcript in a medium with H2O2 and a 3-fold induction in a medium with peroxyacetic acid. For the MohyBpox2 paralog the induction patterns were up to 12-fold and 6.7-fold, respectively. We have successfully expressed the shorter gene, MohyBpox1, heterologously in Pichia pastoris for detailed characterization. Observed biochemical and biophysical properties of the highly purified protein reveal that a typical HyBPOX is significantly different from previously investigated APx-CcP hybrids. This newly discovered secretory peroxidase reveals a Soret maximum at 407 nm, Q bands at 532 and 568 nm, CT band at 625 nm and a purity number of 1.48. Electron paramagnetic resonance (EPR) analysis suggests a mixture of high and low spin species in the ferric state dependent on calcium contents. Steady-state kinetic data reveal the highest peroxidase activity with ABTS, 5-aminosalycilate and efficient oxidation of tyrosine. MoHyBPOX1 as a fusion protein consists of two domains. The longer conserved N-terminal peroxidase domain is connected with a shorter C-terminal domain containing a carbohydrate binding motif of type CBM21. We demonstrate the capacity of MoHyBPOX1 to bind soluble starch efficiently. Potential involvement of hybrid peroxidases in the pathogenicity of M. oryzae is discussed.
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Škodová-Sveráková I, Záhonová K, Bučková B, Füssy Z, Yurchenko V, Lukeš J. Catalase and Ascorbate Peroxidase in Euglenozoan Protists. Pathogens 2020; 9:pathogens9040317. [PMID: 32344595 PMCID: PMC7237987 DOI: 10.3390/pathogens9040317] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Revised: 04/21/2020] [Accepted: 04/22/2020] [Indexed: 11/16/2022] Open
Abstract
In this work, we studied the biochemical properties and evolutionary histories of catalase (CAT) and ascorbate peroxidase (APX), two central enzymes of reactive oxygen species detoxification, across the highly diverse clade Eugenozoa. This clade encompasses free-living phototrophic and heterotrophic flagellates, as well as obligate parasites of insects, vertebrates, and plants. We present evidence of several independent acquisitions of CAT by horizontal gene transfers and evolutionary novelties associated with the APX presence. We posit that Euglenozoa recruit these detoxifying enzymes for specific molecular tasks, such as photosynthesis in euglenids and membrane-bound peroxidase activity in kinetoplastids and some diplonemids.
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Affiliation(s)
- Ingrid Škodová-Sveráková
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, 370 05 České Budějovice (Budweis), Czech Republic;
- Faculty of Natural Sciences, Comenius University, 841 04 Bratislava, Slovakia;
- Correspondence: (I.Š.-S.); (J.L.)
| | - Kristína Záhonová
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, 370 05 České Budějovice (Budweis), Czech Republic;
- Faculty of Science, Charles University, BIOCEV, 128 00 Prague, Czech Republic;
| | - Barbora Bučková
- Faculty of Natural Sciences, Comenius University, 841 04 Bratislava, Slovakia;
| | - Zoltán Füssy
- Faculty of Science, Charles University, BIOCEV, 128 00 Prague, Czech Republic;
| | - Vyacheslav Yurchenko
- Life Science Research Centre, Faculty of Science, University of Ostrava, 710 00 Ostrava, Czech Republic;
- Martsinovsky Institute of Medical Parasitology, Tropical and Vector Borne Diseases, Sechenov University, 119435 Moscow, Russia
| | - Julius Lukeš
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, 370 05 České Budějovice (Budweis), Czech Republic;
- Faculty of Sciences, University of South Bohemia, 370 05 České Budějovice (Budweis), Czech Republic
- Correspondence: (I.Š.-S.); (J.L.)
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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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Ozasa K, Won J, Song S, Maeda M. Behavior of Euglena gracilis under simultaneous competing optical and chemical stimuli. ALGAL RES 2018. [DOI: 10.1016/j.algal.2018.08.013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Hasan MT, Sun A, Mirzaei M, Te'o J, Hobba G, Sunna A, Nevalainen H. A comprehensive assessment of the biosynthetic pathways of ascorbate, α-tocopherol and free amino acids in Euglena gracilis var. saccharophila. ALGAL RES 2017. [DOI: 10.1016/j.algal.2017.08.029] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Biochemistry and Physiology of Reactive Oxygen Species in Euglena. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 979:47-64. [PMID: 28429317 DOI: 10.1007/978-3-319-54910-1_4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Reactive oxygen species (ROS) such as superoxide and hydrogen peroxide are by-products of various metabolic processes in aerobic organisms including Euglena. Chloroplasts and mitochondria are the main sites of ROS generation by photosynthesis and respiration, respectively, through the active electron transport chain. An efficient antioxidant network is required to maintain intracellular ROS pools at optimal conditions for redox homeostasis. A comparison with the networks of plants and animals revealed that Euglena has acquired some aspects of ROS metabolic process. Euglena lacks catalase and a typical selenocysteine containing animal-type glutathione peroxidase for hydrogen peroxide scavenging, but contains enzymes involved in ascorbate-glutathione cycle solely in the cytosol. Ascorbate peroxidase in Euglena, which plays a central role in the ascorbate-glutathione cycle, forms a unique intra-molecular dimer structure that is related to the recognition of peroxides. We recently identified peroxiredoxin and NADPH-dependent thioredoxin reductase isoforms in cellular compartments including chloroplasts and mitochondria, indicating the physiological significance of the thioredoxin system in metabolism of ROS. Besides glutathione, Euglena contains the unusual thiol compound trypanothione, an unusual form of glutathione involving two molecules of glutathione joined by a spermidine linker, which has been identified in pathogenic protists such as Trypanosomatida and Schizopyrenida. Furthermore, in contrast to plants, photosynthesis by Euglena is not susceptible to hydrogen peroxide because of resistance of the Calvin cycle enzymes fructose-1,6-bisphosphatse, NADP+-glyceraldehyde-3-phosphatase, sedoheptulose-1,7-bisphosphatase, and phosphoribulokinase to hydrogen peroxide. Consequently, these characteristics of Euglena appear to exemplify a strategy for survival and adaptation to various environmental conditions during the evolutionary process of euglenoids.
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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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Fungal Hybrid B heme peroxidases - unique fusions of a heme peroxidase domain with a carbohydrate-binding domain. Sci Rep 2017; 7:9393. [PMID: 28839281 PMCID: PMC5571214 DOI: 10.1038/s41598-017-09581-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Accepted: 07/26/2017] [Indexed: 01/03/2023] Open
Abstract
Heme peroxidases, essential peroxide converting oxidoreductases are divided into four independently evolved superfamilies. Within the largest one – the peroxidase-catalase superfamily - two hybrid lineages were described recently. Whereas Hybrid A heme peroxidases represent intermediate enzymes between ascorbate peroxidases and cytochrome c peroxidases, Hybrid B heme peroxidases are unique fusion proteins comprised of a conserved N-terminal heme peroxidase domain and a C-terminal domain of various sugar binding motifs. So far these peculiar peroxidases are only found in the kingdom of Fungi. Here we present a phylogenetic reconstruction of the whole superfamily with focus on Hybrid B peroxidases. We analyse the domain assembly and putative structure and function of the newly discovered oligosaccharide binding domains. Two distinct carbohydrate binding modules (CBM21 and CBM34) are shown to occur in phytopathogenic ascomycetous orthologs of Hybrid B heme peroxidases only. Based on multiple sequence alignment and homology modeling the structure-function relationships are discussed with respect to physiological function. A concerted action of peroxide cleavage with specific cell-wall carbohydrate binding can support phytopathogens survival within the plant host.
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Ozasa K, Won J, Song S, Tamaki S, Ishikawa T, Maeda M. Temporal change of photophobic step-up responses of Euglena gracilis investigated through motion analysis. PLoS One 2017; 12:e0172813. [PMID: 28234984 PMCID: PMC5325543 DOI: 10.1371/journal.pone.0172813] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Accepted: 02/09/2017] [Indexed: 11/28/2022] Open
Abstract
The adaptation to a strong light is one of the essential characteristics of green algae, yet lacking relatively the information about the photophobic responses of Eukaryotic microalgae. We investigated the photophobic step-up responses of Euglena gracilis over a time course of several hours with alternated repetition of blue-light pulse illumination and spatially patterned blue-light illumination. Four distinctive photophobic motions in response to strong blue light were identified in a trace image analysis, namely on-site rotation, running and tumbling, continuous circular swimming, and unaffected straightforward swimming. The cells cultured in autotrophic conditions under weak light showed mainly the on-site rotation response at the beginning of blue-light illumination, but they acquired more blue-light tolerant responses of running and tumbling, circular swimming, or straightforward swimming. The efficiency of escaping from a blue-light illuminated area improved markedly with the development of these photophobic motions. Time constant of 3.0 h was deduced for the evolution of photophobic responses of E. gracilis. The nutrient-rich metabolic status of the cells resulting from photosynthesis during the experiments, i.e., the accumulation of photosynthesized nutrient products in balance between formation and consumption, was the main factor responsible for the development of photophobic responses. The reduction-oxidation status in and around E. gracilis cells did not affect their photophobic responses significantly, unlike the case of photophobic responses and phototaxis of Chlamydomonas reinhardtii cells. This study shows that the evolution of photophobic motion type of E. gracilis is dominated mainly by the nutrient metabolic status of the cells. The fact suggests that the nutrient-rich cells have a higher threshold for switching the flagellar motion from straightforward swimming to rotation under a strong light.
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Affiliation(s)
| | - June Won
- Department of Mechanical Convergence Engineering, Hanyang University, Seongdong-gu, Seoul, Korea
| | - Simon Song
- Department of Mechanical Convergence Engineering, Hanyang University, Seongdong-gu, Seoul, Korea
- Institute of Nano Science and Technology, Hanyang University, Seongdong-gu, Seoul, Korea
| | - Shun Tamaki
- Department of Applied Bioscience 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
| | - Takahiro Ishikawa
- Department of Applied Bioscience 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
| | - Mizuo Maeda
- Bioengineering Lab, RIKEN, Wako, Saitama, Japan
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16
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Maruta T, Sawa Y, Shigeoka S, Ishikawa T. Diversity and Evolution of Ascorbate Peroxidase Functions in Chloroplasts: More Than Just a Classical Antioxidant Enzyme? PLANT & CELL PHYSIOLOGY 2016; 57:1377-1386. [PMID: 26738546 DOI: 10.1093/pcp/pcv203] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Accepted: 12/15/2015] [Indexed: 05/26/2023]
Abstract
Reactive oxygen species (ROS) have dual functions in plant cells as cytotoxic molecules and emergency signals. The balance between the production and scavenging of these molecules in chloroplasts, major sites for the production of ROS, is one of the key determinants for plant acclimation to stress conditions. The water-water cycle is a crucial regulator of ROS levels in chloroplasts. In this cycle, the stromal and thylakoid membrane-attached isoforms of ascorbate peroxidase (sAPX and tAPX, respectively) are involved in the metabolism of H2O2 Current genome and phylogenetic analyses suggest that the first monofunctional APX was generated as sAPX in unicellular green algae, and that tAPX occurred in multicellular charophytes during plant evolution. Chloroplastic APXs, especially tAPX, have been considered to be the source of a bottleneck in the water-water cycle, at least in higher plants, because of their high susceptibility to H2O2 A number of studies have succeeded in improving plant stress resistance by reinforcing the fragile characteristics of the enzymes. However, researchers have unexpectedly failed to find a 'stress-sensitive phenotype' among loss-of-function mutants, at least in laboratory conditions. Interestingly, the susceptibility of enzymes to H2O2 may have been acquired during plant evolution, thereby allowing for the flexible use of H2O2 as a signaling molecule in plants, and this is supported by growing lines of evidence for the physiological significance of chloroplastic H2O2 as a retrograde signal in plant stress responses. By overviewing historical, biochemical, physiological and genetic studies, we herein discuss the diverse functions of chloroplastic APXs as antioxidant enzymes and signaling modulators.
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Affiliation(s)
- Takanori Maruta
- Department of Life Science and Biotechnology, Faculty of Life and Environmental Science, Shimane University, 1060 Nishikawatsu, Matsue, Shimane, 690-8504 Japan
- T.M. currently holds an additional post at the Department of Plant Systems Biology, VIB/Ghent University (Technologiepark 927, 9052 Ghent, Belgium)
| | - Yoshihiro Sawa
- Department of Life Science and Biotechnology, Faculty of Life and Environmental Science, Shimane University, 1060 Nishikawatsu, Matsue, Shimane, 690-8504 Japan
| | - Shigeru Shigeoka
- Department of Advanced Bioscience, Faculty of Agriculture, Kinki University, 3327-204 Nakamachi, Nara, 631-8505 Japan
| | - Takahiro Ishikawa
- Department of Life Science and Biotechnology, Faculty of Life and Environmental Science, Shimane University, 1060 Nishikawatsu, Matsue, Shimane, 690-8504 Japan
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O'Neill EC, Trick M, Hill L, Rejzek M, Dusi RG, Hamilton CJ, Zimba PV, Henrissat B, Field RA. The transcriptome of Euglena gracilis reveals unexpected metabolic capabilities for carbohydrate and natural product biochemistry. MOLECULAR BIOSYSTEMS 2016; 11:2808-20. [PMID: 26289754 DOI: 10.1039/c5mb00319a] [Citation(s) in RCA: 88] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Euglena gracilis is a highly complex alga belonging to the green plant line that shows characteristics of both plants and animals, while in evolutionary terms it is most closely related to the protozoan parasites Trypanosoma and Leishmania. This well-studied organism has long been known as a rich source of vitamins A, C and E, as well as amino acids that are essential for the human diet. Here we present de novo transcriptome sequencing and preliminary analysis, providing a basis for the molecular and functional genomics studies that will be required to direct metabolic engineering efforts aimed at enhancing the quality and quantity of high value products from E. gracilis. The transcriptome contains over 30,000 protein-encoding genes, supporting metabolic pathways for lipids, amino acids, carbohydrates and vitamins, along with capabilities for polyketide and non-ribosomal peptide biosynthesis. The metabolic and environmental robustness of Euglena is supported by a substantial capacity for responding to biotic and abiotic stress: it has the capacity to deploy three separate pathways for vitamin C (ascorbate) production, as well as producing vitamin E (α-tocopherol) and, in addition to glutathione, the redox-active thiols nor-trypanothione and ovothiol.
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Affiliation(s)
- Ellis C O'Neill
- Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich, NR4 7UH, UK.
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Ogawa T, Kimura A, Sakuyama H, Tamoi M, Ishikawa T, Shigeoka S. Identification and characterization of cytosolic fructose-1,6-bisphosphatase in Euglena gracilis. Biosci Biotechnol Biochem 2015. [DOI: 10.1080/09168451.2015.1069694] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Abstract
Euglena gracilis has the ability to accumulate a storage polysaccharide, a β-1,3-glucan known as paramylon, under aerobic conditions. Under anaerobic conditions, E. gracilis cells degrade paramylon and synthesize wax esters. Cytosolic fructose-1,6-bisphosphatase (FBPase) appears to be a key enzyme in gluconeogenesis and position branch point of carbon partitioning between paramylon and wax ester biosynthesis. We herein identified and characterized cytosolic FBPase from E. gracilis. The Km and Vmax values of EgFBPaseIII were 16.5 ± 1.6 μM and 30.4 ± 7.2 μmol min−1 mg protein−1, respectively. The activity of EgFBPaseIII was not regulated by AMP or reversible redox modulation. No significant differences were observed in the production of paramylon in transiently suppressed EgFBPaseIII gene expression cells by RNAi (KD-EgFBPaseIII); nevertheless, FBPase activity was markedly decreased in KD-EgFBPaseIII cells. On the other hand, the growth of KD-EgFBPaseIII cells was slightly higher than that of control cells.
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Affiliation(s)
- Takahisa Ogawa
- Faculty of Agriculture, Department of Advanced Bioscience, Kinki University, Nara, Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Chiyoda-ku, Japan
| | - Ayako Kimura
- Faculty of Agriculture, Department of Advanced Bioscience, Kinki University, Nara, Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Chiyoda-ku, Japan
| | - Harumi Sakuyama
- Faculty of Agriculture, Department of Advanced Bioscience, Kinki University, Nara, Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Chiyoda-ku, Japan
| | - Masahiro Tamoi
- Faculty of Agriculture, Department of Advanced Bioscience, Kinki University, Nara, Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Chiyoda-ku, Japan
| | - Takahiro Ishikawa
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Chiyoda-ku, Japan
- Faculty of Life and Environmental Science, Shimane University, Matsue, Japan
| | - Shigeru Shigeoka
- Faculty of Agriculture, Department of Advanced Bioscience, Kinki University, Nara, Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Chiyoda-ku, Japan
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Tamaki S, Maruta T, Sawa Y, Shigeoka S, Ishikawa T. Biochemical and physiological analyses of NADPH-dependent thioredoxin reductase isozymes in Euglena gracilis. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2015; 236:29-36. [PMID: 26025518 DOI: 10.1016/j.plantsci.2015.03.016] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Revised: 03/14/2015] [Accepted: 03/23/2015] [Indexed: 06/04/2023]
Abstract
At least four peroxiredoxins that are coupled with the thioredoxin (Trx) system have been shown to play a key role in redox metabolism in the unicellular phytoflagellate Euglena gracilis. In order to clarify Trx-mediated redox regulation in this alga, we herein identified three NADPH-dependent thioredoxin reductases (NTRs) using a homologous search and characterized their enzymatic properties and physiological roles. Each Euglena NTR protein belonged to the small, large, and NTRC types, and were named EgNTR1, EgNTR2, and EgNTRC, respectively. EgNTR2 was phylogenetically different from the known NTRs in eukaryotic algae. EgNTR1 was predicted to be localized in mitochondria, EgNTR2 in the cytosol, and EgNTRC in plastids. The catalytic efficiency of EgNTR2 for NADPH was 30-46-fold higher than those of EgNTR1 and truncated form of EgNTRC, suggested that large type EgNTR2 reduced Trx more efficiently. The silencing of EgNTR2 gene expression resulted in significant growth inhibition and cell hypertrophy in Euglena cells. These results suggest that EgNTRs function in each cellular compartment and are physiologically important, particularly in the cytosol.
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Affiliation(s)
- Shun Tamaki
- Department of Life Science and Biotechnology, Faculty of Life and Environmental Science, Shimane University, 1060 Nishikawatsu, Matsue, Shimane 690-8504, 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
| | - Yoshihiro Sawa
- Department of Life Science and Biotechnology, Faculty of Life and Environmental Science, Shimane University, 1060 Nishikawatsu, Matsue, Shimane 690-8504, Japan
| | - Shigeru Shigeoka
- Department of Advanced Bioscience, Faculty of Agriculture, Kinki University, 3327-204 Nakamachi, Nara 631-8505, Japan; Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Chiyoda-ku, Tokyo 102-0076, 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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20
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Characterization and physiological role of two types of chloroplastic fructose-1,6-bisphosphatases in Euglena gracilis. Arch Biochem Biophys 2015; 575:61-8. [DOI: 10.1016/j.abb.2015.04.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Revised: 04/10/2015] [Accepted: 04/13/2015] [Indexed: 11/20/2022]
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Shigeoka S, Maruta T. Cellular redox regulation, signaling, and stress response in plants. Biosci Biotechnol Biochem 2015; 78:1457-70. [PMID: 25209493 DOI: 10.1080/09168451.2014.942254] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Cellular and organellar redox states, which are characterized by the balance between oxidant and antioxidant pool sizes, play signaling roles in the regulation of gene expression and protein function in a wide variety of plant physiological processes including stress acclimation. Reactive oxygen species (ROS) and ascorbic acid (AsA) are the most abundant oxidants and antioxidants, respectively, in plant cells; therefore, the metabolism of these redox compounds must be strictly and spatiotemporally controlled. In this review, we provided an overview of our previous studies as well as recent advances in (1) the molecular mechanisms and regulation of AsA biosynthesis, (2) the molecular and genetic properties of ascorbate peroxidases, and (3) stress acclimation via ROS-derived oxidative/redox signaling pathways, and discussed future perspectives in this field.
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Affiliation(s)
- Shigeru Shigeoka
- a Faculty of Agriculture, Department of Advanced Bioscience , Kinki University , Nara , Japan
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Zámocký M, Hofbauer S, Schaffner I, Gasselhuber B, Nicolussi A, Soudi M, Pirker KF, Furtmüller PG, Obinger C. Independent evolution of four heme peroxidase superfamilies. Arch Biochem Biophys 2015; 574:108-19. [PMID: 25575902 PMCID: PMC4420034 DOI: 10.1016/j.abb.2014.12.025] [Citation(s) in RCA: 151] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2014] [Revised: 12/23/2014] [Accepted: 12/24/2014] [Indexed: 01/19/2023]
Abstract
Four heme peroxidase superfamilies (peroxidase-catalase, peroxidase-cyclooxygenase, peroxidase-chlorite dismutase and peroxidase-peroxygenase superfamily) arose independently during evolution, which differ in overall fold, active site architecture and enzymatic activities. The redox cofactor is heme b or posttranslationally modified heme that is ligated by either histidine or cysteine. Heme peroxidases are found in all kingdoms of life and typically catalyze the one- and two-electron oxidation of a myriad of organic and inorganic substrates. In addition to this peroxidatic activity distinct (sub)families show pronounced catalase, cyclooxygenase, chlorite dismutase or peroxygenase activities. Here we describe the phylogeny of these four superfamilies and present the most important sequence signatures and active site architectures. The classification of families is described as well as important turning points in evolution. We show that at least three heme peroxidase superfamilies have ancient prokaryotic roots with several alternative ways of divergent evolution. In later evolutionary steps, they almost always produced highly evolved and specialized clades of peroxidases in eukaryotic kingdoms with a significant portion of such genes involved in coding various fusion proteins with novel physiological functions.
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Affiliation(s)
- Marcel Zámocký
- Department of Chemistry, Division of Biochemistry, VIBT - Vienna Institute of BioTechnology, University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria; Institute of Molecular Biology, Slovak Academy of Sciences, Dúbravská cesta 21, SK-84551 Bratislava, Slovakia.
| | - Stefan Hofbauer
- Department of Chemistry, Division of Biochemistry, VIBT - Vienna Institute of BioTechnology, University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria; Department for Structural and Computational Biology, Max F. Perutz Laboratories, University of Vienna, A-1030 Vienna, Austria
| | - Irene Schaffner
- Department of Chemistry, Division of Biochemistry, VIBT - Vienna Institute of BioTechnology, University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
| | - Bernhard Gasselhuber
- Department of Chemistry, Division of Biochemistry, VIBT - Vienna Institute of BioTechnology, University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
| | - Andrea Nicolussi
- Department of Chemistry, Division of Biochemistry, VIBT - Vienna Institute of BioTechnology, University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
| | - Monika Soudi
- Department of Chemistry, Division of Biochemistry, VIBT - Vienna Institute of BioTechnology, University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
| | - Katharina F Pirker
- Department of Chemistry, Division of Biochemistry, VIBT - Vienna Institute of BioTechnology, University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
| | - Paul G Furtmüller
- Department of Chemistry, Division of Biochemistry, VIBT - Vienna Institute of BioTechnology, University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
| | - Christian Obinger
- Department of Chemistry, Division of Biochemistry, VIBT - Vienna Institute of BioTechnology, University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
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Nakazawa M, Andoh H, Koyama K, Watanabe Y, Nakai T, Ueda M, Sakamoto T, Inui H, Nakano Y, Miyatake K. Alteration of Wax Ester Content and Composition in Euglena gracilis with Gene Silencing of 3-ketoacyl-CoA Thiolase Isozymes. Lipids 2015; 50:483-92. [PMID: 25860691 DOI: 10.1007/s11745-015-4010-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2014] [Accepted: 03/03/2015] [Indexed: 10/23/2022]
Abstract
Euglena gracilis produces wax ester under hypoxic and anaerobic culture conditions with a net synthesis of ATP. In wax ester fermentation, fatty acids are synthesized by reversing beta-oxidation in mitochondria. A major species of wax ester produced by E. gracilis is myristyl myristate (14:0-14:0Alc). Because of its shorter carbon chain length with saturated compounds, biodiesel produced from E. gracilis wax ester may have good cold flow properties with high oxidative stability. We reasoned that a slight metabolic modification would enable E. gracilis to produce a biofuel of ideal composition. In order to produce wax ester with shorter acyl chain length, we focused on isozymes of the enzyme 3-ketoacyl-CoA thiolase (KAT), a condensing enzyme of the mitochondrial fatty acid synthesis pathway in E. gracilis. We performed a gene silencing study of KAT isozymes in E. gracilis. Six KAT isozymes were identified in the E. gracilis EST database, and silencing any three of them (EgKAT1-3) altered the wax ester amount and composition. In particular, silencing EgKAT1 induced a significant compositional shift to shorter carbon chain lengths in wax ester. A model fuel mixture inferred from the composition of wax ester in EgKAT1-silenced cells showed a significant decrease in melting point compared to that of the control cells.
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Affiliation(s)
- Masami Nakazawa
- Department of Applied Biological Chemistry, Osaka Prefecture University, Osaka, 599-8531, Japan,
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Wheeler G, Ishikawa T, Pornsaksit V, Smirnoff N. Evolution of alternative biosynthetic pathways for vitamin C following plastid acquisition in photosynthetic eukaryotes. eLife 2015; 4. [PMID: 25768426 PMCID: PMC4396506 DOI: 10.7554/elife.06369] [Citation(s) in RCA: 88] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2015] [Accepted: 03/12/2015] [Indexed: 01/08/2023] Open
Abstract
Ascorbic acid (vitamin C) is an enzyme co-factor in eukaryotes that also plays a critical role in protecting photosynthetic eukaryotes against damaging reactive oxygen species derived from the chloroplast. Many animal lineages, including primates, have become ascorbate auxotrophs due to the loss of the terminal enzyme in their biosynthetic pathway, l-gulonolactone oxidase (GULO). The alternative pathways found in land plants and Euglena use a different terminal enzyme, l-galactonolactone dehydrogenase (GLDH). The evolutionary processes leading to these differing pathways and their contribution to the cellular roles of ascorbate remain unclear. Here we present molecular and biochemical evidence demonstrating that GULO was functionally replaced with GLDH in photosynthetic eukaryote lineages following plastid acquisition. GULO has therefore been lost repeatedly throughout eukaryote evolution. The formation of the alternative biosynthetic pathways in photosynthetic eukaryotes uncoupled ascorbate synthesis from hydrogen peroxide production and likely contributed to the rise of ascorbate as a major photoprotective antioxidant. DOI:http://dx.doi.org/10.7554/eLife.06369.001 Animals, plants, algae and other eukaryotic organisms all need vitamin C to enable many of their enzymes to work properly. Vitamin C also protects plant and algal cells from damage by molecules called reactive oxygen species (ROS), which can be produced when these cells harvest energy from sunlight in a process called photosynthesis. Photosynthesis occurs inside structures called chloroplasts, and has evolved on multiple occasions in eukaryotes when non-photosynthetic organisms acquired chloroplasts from other algae and then had to develop improved defences against ROS. There are several steps involved in the production of vitamin C. In many animals, an enzyme called GULO carries out the final step by converting a molecule known as an aldonolactone into vitamin C; this reaction also produces ROS as a waste product. The GULO enzyme is missing in humans, primates and some other groups of animals, so these organisms must get all the vitamin C they need from their diet. Plants and algae use a different enzyme—called GLDH—to make vitamin C from aldonolactone. GLDH is very similar to GULO, but it does not produce ROS as a waste product. It is not clear how the different pathways have evolved, or why some animals have lost the ability to make their own vitamin C. Here, Wheeler et al. used genetics and biochemistry to investigate the evolutionary origins of vitamin C production in a variety of eukaryotic organisms. This investigation revealed that although GULO is missing from the insects and several other groups of animals, it is present in the sponges and many other eukaryotes. This suggests that GULO evolved in early eukaryotic organisms and has since been lost by the different groups of animals. On the other hand, GLDH is only found in plants and the other eukaryotes that can photosynthesize. Wheeler et al.'s findings suggest that GULO has been lost and replaced by GLDH in all plants and algae following their acquisition of chloroplasts. GDLH allows plants and algae to make vitamin C without also producing ROS, which could explain why vitamin C has been able to take on an extra role in these organisms. The results allow us to better understand the functions of vitamin C in photosynthetic organisms and the processes associated with the acquisition of chloroplasts during evolution. DOI:http://dx.doi.org/10.7554/eLife.06369.002
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Affiliation(s)
- Glen Wheeler
- Marine Biological Association, Plymouth, United Kingdom
| | - Takahiro Ishikawa
- Department of Life Science and Biotechnology, Shimane University, Matsue, Japan
| | - Varissa Pornsaksit
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, United Kingdom
| | - Nicholas Smirnoff
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, United Kingdom
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Zámocký M, Gasselhuber B, Furtmüller PG, Obinger C. Turning points in the evolution of peroxidase-catalase superfamily: molecular phylogeny of hybrid heme peroxidases. Cell Mol Life Sci 2014; 71:4681-96. [PMID: 24846396 PMCID: PMC4232752 DOI: 10.1007/s00018-014-1643-y] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2014] [Revised: 04/30/2014] [Accepted: 05/02/2014] [Indexed: 11/27/2022]
Abstract
Heme peroxidases and catalases are key enzymes of hydrogen peroxide metabolism and signaling. Here, the reconstruction of the molecular evolution of the peroxidase-catalase superfamily (annotated in pfam as PF00141) based on experimentally verified as well as numerous newly available genomic sequences is presented. The robust phylogenetic tree of this large enzyme superfamily was obtained from 490 full-length protein sequences. Besides already well-known families of heme b peroxidases arranged in three main structural classes, completely new (hybrid type) peroxidase families are described being located at the border of these classes as well as forming (so far missing) links between them. Hybrid-type A peroxidases represent a minor eukaryotic subfamily from Excavates, Stramenopiles and Rhizaria sharing enzymatic and structural features of ascorbate and cytochrome c peroxidases. Hybrid-type B peroxidases are shown to be spread exclusively among various fungi and evolved in parallel with peroxidases in land plants. In some ascomycetous hybrid-type B peroxidases, the peroxidase domain is fused to a carbohydrate binding (WSC) domain. Both here described hybrid-type peroxidase families represent important turning points in the complex evolution of the whole peroxidase-catalase superfamily. We present and discuss their phylogeny, sequence signatures and putative biological function.
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Affiliation(s)
- Marcel Zámocký
- Division of Biochemistry, Department of Chemistry, VIBT, Vienna Institute of BioTechnology, BOKU, University of Natural Resources and Life Sciences, Muthgasse 18, 1190, Vienna, Austria,
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Tamaki S, Maruta T, Sawa Y, Shigeoka S, Ishikawa T. Identification and functional analysis of peroxiredoxin isoforms in Euglena gracilis. Biosci Biotechnol Biochem 2014; 78:593-601. [DOI: 10.1080/09168451.2014.890037] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Abstract
Euglena gracilis lacks catalase and contains ascorbate peroxidase (APX) which is localized exclusively in the cytosol. Other enzymes that scavenge reactive oxygen species (ROS) in Euglena have not yet been identified; therefore, ROS metabolism, especially in organelles, remains unclear in Euglena. The full-length cDNAs of four Euglena peroxiredoxins (EgPrxs) were isolated in this study. EgPrx1 and -4 were predicted to be localized in the cytosol, and EgPrx2 and -3 in plastids and mitochondria, respectively. The catalytic efficiencies of recombinant EgPrxs were similar to those of plant thiol-peroxidases, but were markedly lower than those of APX from Euglena. However, transcript levels of EgPrx1, -2, and -3 were markedly higher than those of APX. The growth rate of Euglena cells, in which the expression of EgPrx1 and -4 was suppressed by gene silencing, was markedly reduced under normal conditions, indicating physiological significance of Prx proteins.
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Affiliation(s)
- Shun Tamaki
- Faculty of Life and Environmental Science, Department of Life Science and Biotechnology, Shimane University, Matsue, Japan
| | - Takanori Maruta
- Faculty of Life and Environmental Science, Department of Life Science and Biotechnology, Shimane University, Matsue, Japan
| | - Yoshihiro Sawa
- Faculty of Life and Environmental Science, Department of Life Science and Biotechnology, Shimane University, Matsue, Japan
| | - Shigeru Shigeoka
- Faculty of Agriculture, Department of Advanced Bioscience, Kinki University, Nara, Japan
| | - Takahiro Ishikawa
- Faculty of Life and Environmental Science, Department of Life Science and Biotechnology, Shimane University, Matsue, Japan
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Camillo LR, Filadelfo CR, Monzani PS, Corrêa RX, Gramacho KP, Micheli F, Pirovani CP. Tc-cAPX, a cytosolic ascorbate peroxidase of Theobroma cacao L. engaged in the interaction with Moniliophthora perniciosa, the causing agent of witches' broom disease. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2013; 73:254-265. [PMID: 24161755 DOI: 10.1016/j.plaphy.2013.10.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2013] [Accepted: 10/04/2013] [Indexed: 06/02/2023]
Abstract
The level of hydrogen peroxide (H2O2) in plants signalizes the induction of several genes, including that of ascorbate peroxidase (APX-EC 1.11.1.11). APX isoenzymes play a central role in the elimination of intracellular H2O2 and contribute to plant responses to diverse stresses. During the infection process in Theobroma cacao by Moniliophthora perniciosa oxidative stress is generated and the APX action recruited from the plant. The present work aimed to characterize the T. cacao APX involved in the molecular interaction of T. cacao-M. perniciosa. The peroxidase activity was analyzed in protein extracts from cocoa plants infected by M. perniciosa and showed the induction of peroxidases like APX in resistant cocoa plants. The cytosolic protein of T. cacao (GenBank: ABR68691.2) was phylogenetically analyzed in relation to other peroxidases from the cocoa genome and eight genes encoding APX proteins with conserved domains were also analyzed. The cDNA from cytosolic APX was cloned in pET28a and the recombinant protein expressed and purified (rTc-cAPX). The secondary structure of the protein was analyzed by Circular Dichroism (CD) displaying high proportion of α-helices when folded. The enzymatic assay shows stable activity using ascorbate and guaiacol as an electron donor for H2O2 reduction. The pH 7.5 is the optimum for enzyme activity. Chromatographic analysis suggests that rTc-cAPX is a homodimer in solution. Results indicate that the rTc-cAPX is correctly folded, stable and biochemically active. The purified rTc-cAPX presented biotechnological potential and is adequate for future structural and functional studies.
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Affiliation(s)
- Luciana Rodrigues Camillo
- Centro de Biotecnologia e Genética, Universidade Estadual de Santa Cruz - UESC, Rodovia Jorge Amado Km 16, 45662-900 Ilhéus, BA, Brazil
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28
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Yabuta Y, Takamatsu R, Kasagaki S, Watanabe F. Isolation and Expression of a cDNA Encoding Methylmalonic Aciduria Type A Protein from Euglena gracilis Z. Metabolites 2013; 3:144-54. [PMID: 24957894 PMCID: PMC3901258 DOI: 10.3390/metabo3010144] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2012] [Revised: 02/06/2013] [Accepted: 02/07/2013] [Indexed: 11/16/2022] Open
Abstract
In animals, cobalamin (Cbl) is a cofactor for methionine synthase and methylmalonyl-CoA mutase (MCM), which utilizes methylcobalamin and 5'-deoxyadenosylcobalamin (AdoCbl), respectively. The cblA complementation class of inborn errors of Cbl metabolism in humans is one of three known disorders that affect AdoCbl synthesis. The gene responsible for cblA has been identified in humans (MMAA) as well as its homolog (meaB) in Methylobacterium extorquens. Recently, it has been reported that human MMAA plays an important role in the protection and reactivation of MCM in vitro. However, the physiological function of MMAA is largely unknown. In the present study, we isolated the cDNA encoding MMAA from Euglena gracilis Z, a photosynthetic flagellate. The deduced amino acid sequence of the cDNA shows 79%, 79%, 79% and 80% similarity to human, mouse, Danio rerio MMAAs and M. extorquens MeaB, respectively. The level of the MCM transcript was higher in Cbl-deficient cultures of E. gracilis than in those supplemented with Cbl. In contrast, no significant differences were observed in the levels of the MMAA transcript under the same two conditions. No significant difference in MCM activity was observed between Escherichia coli that expressed either MCM together with MMAA or expressed MCM alone.
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Affiliation(s)
- Yukinori Yabuta
- School of Agricultural, Biological, and Environmental Sciences, Faculty of Agriculture, Tottori University, 4-101 Koyama-Minami, Tottori 680-8553, Japan.
| | - Ryota Takamatsu
- School of Agricultural, Biological, and Environmental Sciences, Faculty of Agriculture, Tottori University, 4-101 Koyama-Minami, Tottori 680-8553, Japan.
| | - Satoshi Kasagaki
- School of Agricultural, Biological, and Environmental Sciences, Faculty of Agriculture, Tottori University, 4-101 Koyama-Minami, Tottori 680-8553, Japan.
| | - Fumio Watanabe
- School of Agricultural, Biological, and Environmental Sciences, Faculty of Agriculture, Tottori University, 4-101 Koyama-Minami, Tottori 680-8553, Japan.
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Banerjee S, Zamocky M, Furtmüller PG, Obinger C. Probing the two-domain structure of homodimeric prokaryotic and eukaryotic catalase-peroxidases. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2010; 1804:2136-45. [PMID: 20654740 DOI: 10.1016/j.bbapap.2010.07.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2010] [Revised: 07/04/2010] [Accepted: 07/13/2010] [Indexed: 11/17/2022]
Abstract
Catalase-peroxidases (KatGs) are ancestral bifunctional heme peroxidases found in archaeons, bacteria and lower eukaryotes. In contrast to homologous cytochrome c peroxidase (CcP) and ascorbate peroxidase (APx) homodimeric KatGs have a two-domain monomeric structure with a catalytic N-terminal heme domain and a C-terminal domain of high sequence and structural similarity but without obvious function. Nevertheless, without its C-terminal counterpart the N-terminal domain exhibits neither catalase nor peroxidase activity. Except some hybrid-type proteins all other members of the peroxidase-catalase superfamily lack this C-terminal domain. In order to probe the role of the two-domain monomeric structure for conformational and thermal stability urea and temperature-dependent unfolding experiments were performed by using UV-Vis-, electronic circular dichroism- and fluorescence spectroscopy, as well as differential scanning calorimetry. Recombinant prokaryotic (cyanobacterial KatG from Synechocystis sp. PCC6803) and eukaryotic (fungal KatG from Magnaporthe grisea) were investigated. The obtained data demonstrate that the conformational and thermal stability of bifunctional KatGs is significantly lower compared to homologous monofunctional peroxidases. The N- and C-terminal domains do not unfold independently. Differences between the cyanobacterial and the fungal enzyme are relatively small. Data will be discussed with respect to known structure and function of KatG, CcP and APx.
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Affiliation(s)
- Srijib Banerjee
- Department of Chemistry, Division of Biochemistry, BOKU, University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
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Miyamoto E, Tanioka Y, Nishizawa-Yokoi A, Yabuta Y, Ohnishi K, Misono H, Shigeoka S, Nakano Y, Watanabe F. Characterization of methylmalonyl-CoA mutase involved in the propionate photoassimilation of Euglena gracilis Z. Arch Microbiol 2010; 192:437-46. [PMID: 20379701 DOI: 10.1007/s00203-010-0572-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2010] [Revised: 02/26/2010] [Accepted: 03/24/2010] [Indexed: 11/24/2022]
Affiliation(s)
- Emi Miyamoto
- Department of Health and Nutrition, Nagasaki International University, Sasebo, Japan
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