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Solovchenko A, Lobakova E, Semenov A, Gorelova O, Fedorenko T, Chivkunova O, Parshina E, Maksimov G, Sluchanko NN, Maksimov E. Multimodal non-invasive probing of stress-induced carotenogenesis in the cells of microalga Bracteacoccus aggregatus. PROTOPLASMA 2024; 261:1051-1071. [PMID: 38703269 DOI: 10.1007/s00709-024-01956-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2024] [Accepted: 04/25/2024] [Indexed: 05/06/2024]
Abstract
Microalgae are the richest source of natural carotenoids-accessory photosynthetic pigments used as natural antioxidants, safe colorants, and nutraceuticals. Microalga Bracteacoccus aggregatus IPPAS C-2045 responds to stresses, including high light, with carotenogenesis-gross accumulation of secondary carotenoids (the carotenoids structurally and energetically uncoupled from photosynthesis). Precise mechanisms of cytoplasmic transport and subcellular distribution of the secondary carotenoids under stress are still unknown. Using multimodal imaging combining micro-Raman imaging (MRI), fluorescent lifetime (τ) imaging (FLIM), and transmission electron microscopy (TEM), we monitored ultrastructural and biochemical rearrangements of B. aggregatus cells during the stress-induced carotenogenesis. MRI revealed a decline in the diversity of molecular surrounding of the carotenoids in the cells compatible with the relocation of the bulk of the carotenoids in the cell from functionally and structurally heterogeneous photosynthetic apparatus to the more homogenous lipid matrix of the oleosomes. Two-photon FLIM highlighted the pigment transformation in the cell during the stress-induced carotenogenesis. The structures co-localized with the carotenoids with shorter τ (mainly chloroplast) shrunk, whereas the structures harboring secondary carotenoids with longer τ (mainly oleosomes) expanded. These changes were in line with the ultrastructural data (TEM). Fluorescence of B. aggregatus carotenoids, either in situ or in acetone extracts, possessed a surprisingly long lifetime. We hypothesize that the extension of τ of the carotenoids is due to their aggregation and/or association with lipids and proteins. The propagation of the carotenoids with prolonged τ is considered to be a manifestation of the secondary carotenogenesis suitable for its non-invasive monitoring with multimodal imaging.
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Affiliation(s)
- Alexei Solovchenko
- Department of Bioengineering, Faculty of Biology, Lomonosov Moscow State University, Leninskie Gory 1-12, GSP-1, Moscow, 119234, Russia.
| | - Elena Lobakova
- Department of Bioengineering, Faculty of Biology, Lomonosov Moscow State University, Leninskie Gory 1-12, GSP-1, Moscow, 119234, Russia
| | - Alexey Semenov
- Laboratory of Physics and Chemistry of Biological Membranes, Department of Biology, Lomonosov Moscow State University, Leninskie Gory 1-12, Moscow, 119234, Russia
- Department of Experimental Physics, Saarland University, 66123, Saarbrücken, Germany
| | - Olga Gorelova
- Department of Bioengineering, Faculty of Biology, Lomonosov Moscow State University, Leninskie Gory 1-12, GSP-1, Moscow, 119234, Russia
| | - Tatiana Fedorenko
- Department of Bioengineering, Faculty of Biology, Lomonosov Moscow State University, Leninskie Gory 1-12, GSP-1, Moscow, 119234, Russia
| | - Olga Chivkunova
- Department of Bioengineering, Faculty of Biology, Lomonosov Moscow State University, Leninskie Gory 1-12, GSP-1, Moscow, 119234, Russia
| | - Evgenia Parshina
- Department of Biology, M.V. Lomonosov Moscow State University, Leninskie Gory 1-12, Moscow, 119234, Russia
| | - Georgy Maksimov
- Department of Biology, M.V. Lomonosov Moscow State University, Leninskie Gory 1-12, Moscow, 119234, Russia
| | - Nikolai N Sluchanko
- Federal Research Center of Biotechnology, Russian Academy of Sciences, Leninsky Av. 33, Moscow, 119071, Russia
| | - Eugene Maksimov
- Laboratory of Physics and Chemistry of Biological Membranes, Department of Biology, Lomonosov Moscow State University, Leninskie Gory 1-12, Moscow, 119234, Russia
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Nezafatian E, Farhadian O, Yegdaneh A, Safavi M, Daneshvar E, Bhatnagar A. Enhanced production of bioactive compounds from marine microalgae Tetraselmis tetrathele under salinity and light stresses: A two-stage cultivation strategy. BIORESOURCE TECHNOLOGY 2023; 376:128899. [PMID: 36933578 DOI: 10.1016/j.biortech.2023.128899] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 03/09/2023] [Accepted: 03/11/2023] [Indexed: 06/18/2023]
Abstract
This study leveraged the salinity and light intensity stresses during the stationary phase for enhancing the pigment contents and antioxidant capacity of Tetraselmis tetrathele. The highest pigments content was obtained in cultures under salinity stress (40 g L-1) illuminated using fluorescent light. Furthermore, the best inhibitory concentration (IC50) for scavenging the 2, 2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radicals was found as 79.53 µg mL-1 in ethanol extract and cultures under red LED light stress (300 µmol m-2 s-1). The highest antioxidant capacity in a ferric-reducing antioxidant power (FRAP) assay (1,778.6 µM Fe+2) was found in ethanol extract and cultures under salinity stress illuminated using fluorescent light. Maximum scavenging of the 2.2-diphenyl-1-picrylhydrazyl (DPPH) radical was found in ethyl acetate extracts under light and salinity stresses. These results indicated that abiotic stresses could enhance the pigment and antioxidant components of T. tetrathele, which are value-added compounds in the pharmaceutical, cosmetic, and food industries.
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Affiliation(s)
- Elham Nezafatian
- Department of Natural Resources, Isfahan University of Technology, Isfahan 84156-83111, Iran
| | - Omidvar Farhadian
- Department of Natural Resources, Isfahan University of Technology, Isfahan 84156-83111, Iran.
| | - Afsaneh Yegdaneh
- Department of Pharmacognosy, School of Pharmacy and Pharmaceutical Sciences and Isfahan Pharmaceutical Sciences Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Maliheh Safavi
- Department of Biotechnology, Iranian Research Organization for Science and Technology (IROST), 3353-5111 Tehran, Iran
| | - Ehsan Daneshvar
- Department of Separation Science, LUT School of Engineering Science, LUT University, Sammonkatu 12, FI-50130 Mikkeli, Finland
| | - Amit Bhatnagar
- Department of Separation Science, LUT School of Engineering Science, LUT University, Sammonkatu 12, FI-50130 Mikkeli, Finland
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Zarekarizi A, Hoffmann L, Burritt DJ. The potential of manipulating light in the commercial production of carotenoids from algae. ALGAL RES 2023. [DOI: 10.1016/j.algal.2023.103047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/11/2023]
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Wood EE, Ross ME, Jubeau S, Montalescot V, Stanley MS. Progress towards a targeted biorefinery of Chromochloris zofingiensis: a review. BIOMASS CONVERSION AND BIOREFINERY 2022; 14:8127-8152. [PMID: 38510795 PMCID: PMC10948469 DOI: 10.1007/s13399-022-02955-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Revised: 06/09/2022] [Accepted: 06/13/2022] [Indexed: 03/22/2024]
Abstract
Biorefinery approaches offer the potential to improve the economics of the microalgae industry by producing multiple products from a single source of biomass. Chromochloris zofingiensis shows great promise for biorefinery due to high biomass productivity and a diverse range of products including secondary carotenoids, predominantly astaxanthin; lipids such as TAGs; carbohydrates including starch; and proteins and essential amino acids. Whilst this species has been demonstrated to accumulate multiple products, the development of an integrated downstream process to obtain these is lacking. The objective of this review paper is to assess the research that has taken place and to identify the steps that must be taken to establish a biorefinery approach for C. zofingiensis. In particular, the reasons why C. zofingiensis is a promising species to target for biorefinery are discussed in terms of cellular structure, potential products, and means to accumulate desirable components via the alteration of culture conditions. Future advances and the challenges that lie ahead for successful biorefinery of this species are also reviewed along with potential solutions to address them. Supplementary Information The online version contains supplementary material available at 10.1007/s13399-022-02955-7.
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Affiliation(s)
- Eleanor E. Wood
- University of the Highlands and Islands (UHI); Scottish Association for Marine Science (SAMS), Scottish Marine Institute, Oban, PA37 1QA UK
- Xanthella Ltd, Malin House, European Marine Science Park, Dunstaffnage, Argyll, Oban PA37 1SZ Scotland, UK
| | - Michael E. Ross
- University of the Highlands and Islands (UHI); Scottish Association for Marine Science (SAMS), Scottish Marine Institute, Oban, PA37 1QA UK
| | - Sébastien Jubeau
- Xanthella Ltd, Malin House, European Marine Science Park, Dunstaffnage, Argyll, Oban PA37 1SZ Scotland, UK
| | | | - Michele S. Stanley
- University of the Highlands and Islands (UHI); Scottish Association for Marine Science (SAMS), Scottish Marine Institute, Oban, PA37 1QA UK
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Enhanced growth of Chromochloris zofingiensis through the transition of nutritional modes. ALGAL RES 2022. [DOI: 10.1016/j.algal.2022.102723] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Maltsev Y, Maltseva K, Kulikovskiy M, Maltseva S. Influence of Light Conditions on Microalgae Growth and Content of Lipids, Carotenoids, and Fatty Acid Composition. BIOLOGY 2021; 10:1060. [PMID: 34681157 PMCID: PMC8533579 DOI: 10.3390/biology10101060] [Citation(s) in RCA: 69] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Revised: 10/13/2021] [Accepted: 10/14/2021] [Indexed: 02/06/2023]
Abstract
Microalgae are a valuable natural resource for a variety of value-added products. The growth of microalgae is determined by the impact of many factors, but, from the point of view of the implementation of autotrophic growth, light is of primary importance. This work presents an overview of the influence of light conditions on the growth of microalgae, the content of lipids, carotenoids, and the composition of fatty acids in their biomass, taking into account parameters such as the intensity, duration of lighting, and use of rays of different spectral composition. The optimal light intensity for the growth of microalgae lies in the following range: 26-400 µmol photons m-2 s-1. An increase in light intensity leads to an activation of lipid synthesis. For maximum lipid productivity, various microalgae species and strains need lighting of different intensities: from 60 to 700 µmol photons m-2 s-1. Strong light preferentially increases the triacylglyceride content. The intensity of lighting has a regulating effect on the synthesis of fatty acids, carotenoids, including β-carotene, lutein and astaxanthin. In intense lighting conditions, saturated fatty acids usually accumulate, as well as monounsaturated ones, and the number of polyunsaturated fatty acids decreases. Red as well as blue LED lighting improves the biomass productivity of microalgae of various taxonomic groups. Changing the duration of the photoperiod, the use of pulsed light can stimulate microalgae growth, the production of lipids, and carotenoids. The simultaneous use of light and other stresses contributes to a stronger effect on the productivity of algae.
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Affiliation(s)
- Yevhen Maltsev
- Laboratory of Molecular Systematics of Aquatic Plants, K.A. Timiryazev Institute of Plant Physiology RAS, IPP RAS, 127276 Moscow, Russia; (M.K.); (S.M.)
| | - Kateryna Maltseva
- Faculty of Chemistry and Biology, Bogdan Khmelnitsky Melitopol State Pedagogical University, 72312 Melitopol, Ukraine;
| | - Maxim Kulikovskiy
- Laboratory of Molecular Systematics of Aquatic Plants, K.A. Timiryazev Institute of Plant Physiology RAS, IPP RAS, 127276 Moscow, Russia; (M.K.); (S.M.)
| | - Svetlana Maltseva
- Laboratory of Molecular Systematics of Aquatic Plants, K.A. Timiryazev Institute of Plant Physiology RAS, IPP RAS, 127276 Moscow, Russia; (M.K.); (S.M.)
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Luo W, Wang Y, Yang P, Qu Y, Yu X. Multilevel Regulation of Carotenoid Synthesis by Light and Active Oxygen in Blakeslea trispora. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2021; 69:10974-10988. [PMID: 34510898 DOI: 10.1021/acs.jafc.1c03389] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Although Blakeslea trispora has been used for industrial production of β-carotene, the effects of light and oxidative stress on its synthesis have not been fully clarified. The present study focuses on the effects of light and reactive oxygen species (ROS) on carotenoid synthesis and their multilevel regulation in B. trispora. Blue light significantly influenced the intracellular ROS levels, carotenoid contents, and transcription of carotenoid structural genes, while ROS levels were positively correlated with intracellular carotenoid contents and transcriptional levels of carotenoid structural genes. Blue light and ROS were both significant factors affecting carotenoid synthesis with a significant interaction between them. Irradiation by pulsed blue light and (or) addition of generating agents for active oxygen could partially compensate for the inhibition derived from the transcription inhibitor (dactinomycin) and translation inhibitor (cycloheximide) on the multilevel phenotype. Therefore, blue light and ROS act on the transcription and translation of carotenoid structural genes to promote the accumulation of carotenoid in B. trispora.
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Affiliation(s)
- Wei Luo
- Key Laboratory of Industrial Biotechnology, Ministry of Education; School of Biotechnology, Jiangnan University, Wuxi 214122, PR China
| | - Ying Wang
- Key Laboratory of Industrial Biotechnology, Ministry of Education; School of Biotechnology, Jiangnan University, Wuxi 214122, PR China
| | - Peilong Yang
- Key Laboratory of Feed Biotechnology, Ministry of Agriculture and Rural Affairs, Beijing 100081, PR China
| | - Yinbo Qu
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, PR China
| | - Xiaobin Yu
- Key Laboratory of Industrial Biotechnology, Ministry of Education; School of Biotechnology, Jiangnan University, Wuxi 214122, PR China
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Zhang Y, Ye Y, Bai F, Liu J. The oleaginous astaxanthin-producing alga Chromochloris zofingiensis: potential from production to an emerging model for studying lipid metabolism and carotenogenesis. BIOTECHNOLOGY FOR BIOFUELS 2021; 14:119. [PMID: 33992124 PMCID: PMC8126118 DOI: 10.1186/s13068-021-01969-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Accepted: 05/07/2021] [Indexed: 05/05/2023]
Abstract
The algal lipids-based biodiesel, albeit having advantages over plant oils, still remains high in the production cost. Co-production of value-added products with lipids has the potential to add benefits and is thus believed to be a promising strategy to improve the production economics of algal biodiesel. Chromochloris zofingiensis, a unicellular green alga, has been considered as a promising feedstock for biodiesel production because of its robust growth and ability of accumulating high levels of triacylglycerol under multiple trophic conditions. This alga is also able to synthesize high-value keto-carotenoids and has been cited as a candidate producer of astaxanthin, the strongest antioxidant found in nature. The concurrent accumulation of triacylglycerol and astaxanthin enables C. zofingiensis an ideal cell factory for integrated production of the two compounds and has potential to improve algae-based production economics. Furthermore, with the advent of chromosome-level whole genome sequence and genetic tools, C. zofingiensis becomes an emerging model for studying lipid metabolism and carotenogenesis. In this review, we summarize recent progress on the production of triacylglycerol and astaxanthin by C. zofingiensis. We also update our understanding in the distinctive molecular mechanisms underlying lipid metabolism and carotenogenesis, with an emphasis on triacylglycerol and astaxanthin biosynthesis and crosstalk between the two pathways. Furthermore, strategies for trait improvements are discussed regarding triacylglycerol and astaxanthin synthesis in C. zofingiensis.
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Affiliation(s)
- Yu Zhang
- Laboratory for Algae Biotechnology and Innovation, College of Engineering, Peking University, Beijing, 100871, China
| | - Ying Ye
- Laboratory for Algae Biotechnology and Innovation, College of Engineering, Peking University, Beijing, 100871, China
| | - Fan Bai
- Laboratory for Algae Biotechnology and Innovation, College of Engineering, Peking University, Beijing, 100871, China
| | - Jin Liu
- Laboratory for Algae Biotechnology and Innovation, College of Engineering, Peking University, Beijing, 100871, China.
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Kou Y, Liu M, Sun P, Dong Z, Liu J. High light boosts salinity stress-induced biosynthesis of astaxanthin and lipids in the green alga Chromochloris zofingiensis. ALGAL RES 2020. [DOI: 10.1016/j.algal.2020.101976] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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10
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Effects of Different Environmental Factors on the Growth and Bioactive Substance Accumulation of Porphyridium purpureum. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2020; 17:ijerph17072221. [PMID: 32224974 PMCID: PMC7177824 DOI: 10.3390/ijerph17072221] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Revised: 03/21/2020] [Accepted: 03/25/2020] [Indexed: 11/17/2022]
Abstract
Genus Porphyridium is a primitive single-celled red algae widely distributed in seawater, freshwater, and moist soil. It can synthesize bioactive substances such as phycoerythrin, extracellular polysaccharides and polyunsaturated fatty acids during the growth process. In this paper, the culture and bioactive substance yield of Porphyridium purpureum were studied by setting salinity, nitrogen-to-phosphorus ratio, and pH at different gradient levels. The results showed that the optimal conditions for the growth of P. purpureum were salinity 34 ppt, nitrogen-to-phosphorus ratio 169:1, and pH 8; the optimal conditions for obtaining the polysaccharides were salinity 17 ppt, nitrogen-to-phosphorus ratio 14:1, and pH 8; the optimal conditions for obtaining phycoerythrin were salinity 17 ppt, nitrogen-to-phosphorus ratio 68:1, and pH 8; the optimal conditions for obtaining the lipids were salinity 34 ppt, nitrogen-to-phosphorus ratio 1:1, and pH 8. In actual production applications, culture conditions should be set according to different product accumulation purposes in order to achieve the optimal production efficiency.
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Lu Z, Dai J, Zheng L, Teng Z, Zhang Q, Qiu D, Song L. Disodium 2-oxoglutarate promotes carbon flux into astaxanthin and fatty acid biosynthesis pathways in Haematococcus. BIORESOURCE TECHNOLOGY 2020; 299:122612. [PMID: 31874452 DOI: 10.1016/j.biortech.2019.122612] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Revised: 12/10/2019] [Accepted: 12/11/2019] [Indexed: 06/10/2023]
Abstract
Improving carbon availability in astaxanthin production is pivotal in Haematococcus industry. In this study, disodium 2-oxoglutarate (2-OG-2Na) was observed to be a potential carbon regulator to increase the astaxanthin content. To illustrate its efficacy in astaxanthin production, key genes and enzyme were analyzed. Upon 2-OG-2Na treatment, genes ipi, bkt and crtR-b were up regulated, concomitantly, carotenoids and astaxanthin content increased by 15.4% and 14.0% at 120 h, respectively; additionally, Acetyl-CoA carboxylase was activated, consistent with 1.27-fold increase in fatty acids content. PUFAs increased earlier as fatty acids assembly gene fad was up-regulated to 20.56. It was also found that cell division was not compromised. Altogether, it was suggested that increased carbon skeletons were re-directed into the astaxanthin and fatty acids biosynthesis pathway. Furthermore, 2-OG-2Na was applied in ten Haematococcus strains. Of these strains, astaxanthin contents were accelerated with average net increase of 10.48%, exhibiting a scalable paradigm for commercial production.
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Affiliation(s)
- Zhe Lu
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Jingcheng Dai
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, PR China
| | - LingLing Zheng
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, PR China
| | - Zhuoran Teng
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Qi Zhang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, PR China
| | - Dongru Qiu
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, PR China
| | - Lirong Song
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China.
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Heuristic Optimization of Culture Conditions for Stimulating Hyper-Accumulation of Biomass and Lipid in Golenkinia SDEC-16. ENERGIES 2020. [DOI: 10.3390/en13040964] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Overproduction of biomass and hyper-accumulation of lipids endow microalgae with promising characteristics to realize the cost-effective potential of advanced bioenergy. This study sought to heuristically optimize the culture conditions on a rarely reported Golenkinia sp. The results indicate that Golenkinia SDEC-16 can withstand the strong light intensity and grow in a modified BG11 medium. The optimal culture conditions for the favorable tradeoff between biomass and lipid accumulation were suggested as follows, 25,000 lux of light intensity, 9 mM of initial nitrogen concentration, and 20 mM of initial sodium chloride concentration. Under these conditions, the biomass concentration and productivity reached 6.65 g/L and 545 mg/L/d, and the synchronous lipid content and productivity reached 54.38% and 296.39 mg/L/d. Hypersalinity significantly promoted lipid contents at the cost of biomass and resulted in an increase of cell size but loss of spines of Golenkinia SDEC-16. The results shed new light on optimizing biomass and lipid productivity.
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Mao X, Zhang Y, Wang X, Liu J. Novel insights into salinity-induced lipogenesis and carotenogenesis in the oleaginous astaxanthin-producing alga Chromochloris zofingiensis: a multi-omics study. BIOTECHNOLOGY FOR BIOFUELS 2020; 13:73. [PMID: 32322303 PMCID: PMC7161124 DOI: 10.1186/s13068-020-01714-y] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Accepted: 04/09/2020] [Indexed: 05/03/2023]
Abstract
BACKGROUND Chromochloris zofingiensis, a freshwater alga capable of synthesizing both triacylglycerol (TAG) and astaxanthin, has been receiving increasing attention as a leading candidate producer. While the mechanism of oleaginousness and/or carotenogenesis has been studied under such induction conditions as nitrogen deprivation, high light and glucose feeding, it remains to be elucidated in response to salt stress, a condition critical for reducing freshwater footprint during algal production processes. RESULTS Firstly, the effect of salt concentrations on growth, lipids and carotenoids was examined for C. zofingiensis, and 0.2 M NaCl demonstrated to be the optimal salt concentration for maximizing both TAG and astaxanthin production. Then, the time-resolved lipid and carotenoid profiles and comparative transcriptomes and metabolomes were generated in response to the optimized salt concentration for congruent analysis. A global response was triggered in C. zofingiensis allowing acclimation to salt stress, including photosynthesis impairment, ROS build-up, protein turnover, starch degradation, and TAG and astaxanthin accumulation. The lipid metabolism involved a set of stimulated biological pathways that contributed to carbon precursors, energy and reductant molecules, pushing and pulling power, and storage sink for TAG accumulation. On the other hand, salt stress suppressed lutein biosynthesis, stimulated astaxanthin biosynthesis (mainly via ketolation), yet had little effect on total carotenoid flux, leading to astaxanthin accumulation at the expense of lutein. Astaxanthin was predominantly esterified and accumulated in a well-coordinated manner with TAG, pointing to the presence of common regulators and potential communication for the two compounds. Furthermore, the comparison between salt stress and nitrogen deprivation conditions revealed distinctions in TAG and astaxanthin biosynthesis as well as critical genes with engineering potential. CONCLUSIONS Our multi-omics data and integrated analysis shed light on the salt acclimation of C. zofingiensis and underlying mechanisms of TAG and astaxanthin biosynthesis, provide engineering implications into future trait improvements, and will benefit the development of this alga for production uses under saline environment, thus reducing the footprint of freshwater.
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Affiliation(s)
- Xuemei Mao
- Laboratory for Algae Biotechnology & Innovation, College of Engineering, Peking University, Beijing, 100871 China
| | - Yu Zhang
- Laboratory for Algae Biotechnology & Innovation, College of Engineering, Peking University, Beijing, 100871 China
| | - Xiaofei Wang
- Laboratory for Algae Biotechnology & Innovation, College of Engineering, Peking University, Beijing, 100871 China
| | - Jin Liu
- Laboratory for Algae Biotechnology & Innovation, College of Engineering, Peking University, Beijing, 100871 China
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Sun Z, Zhang Y, Sun LP, Liu J. Light Elicits Astaxanthin Biosynthesis and Accumulation in the Fermented Ultrahigh-Density Chlorella zofinginesis. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2019; 67:5579-5586. [PMID: 31038310 DOI: 10.1021/acs.jafc.9b01176] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The growth and astaxanthin production of Chlorella zofingiensis were examined under both heterotrophic and photoautotrophic conditions, and it was found that, in comparison to the photoautotrophic mode, the heterotrophic mode led to high algal densities but attenuated intracellular astaxanthin accumulation. Following the heterotrophy-photoautotrophy transition, a considerable increase in the astaxanthin content was observed, accompanied by the upregulation of key carotenogenic genes, including phytoene synthase (PSY), β-carotenoid hydroxylase (CHYb), β-carotenoid ketolase 1 (BKT1), and β-carotenoid ketolase 2 (BKT2). In contrast, the astaxanthin content and carotenogenic genes underwent an opposite change following the photoautotrophy-heterotrophy transition, suggesting the key role of light in stimulating astaxanthin biosynthesis. To improve the astaxanthin production by C. zofingiensis, a novel heterotrophy-photoinduction culture strategy without dilution was developed and evaluated. The astaxanthin content and productivity reached 2.7 mg g-1 of dry weight and 9.9 mg L-1 day-1, respectively, which were 4.0- and 2.5-fold higher than that obtained under the heterotrophic condition.
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Affiliation(s)
- Zheng Sun
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education; International Research Center for Marine Biosciences, Ministry of Science and Technology; National Demonstration Center for Experimental Fisheries Science Education , Shanghai Ocean University , Shanghai 201306 , People's Republic of China
| | - Yu Zhang
- Laboratory for Algae Biotechnology & Innovation, College of Engineering , Peking University , Beijing 100871 , People's Republic of China
| | - Li-Ping Sun
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education; International Research Center for Marine Biosciences, Ministry of Science and Technology; National Demonstration Center for Experimental Fisheries Science Education , Shanghai Ocean University , Shanghai 201306 , People's Republic of China
| | - Jin Liu
- Laboratory for Algae Biotechnology & Innovation, College of Engineering , Peking University , Beijing 100871 , People's Republic of China
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Janchot K, Rauytanapanit M, Honda M, Hibino T, Sirisattha S, Praneenararat T, Kageyama H, Waditee‐Sirisattha R. Effects of Potassium Chloride‐Induced Stress on the Carotenoids Canthaxanthin, Astaxanthin, and Lipid Accumulations in the Green Chlorococcal Microalga StrainTISTR9500. J Eukaryot Microbiol 2019; 66:778-787. [DOI: 10.1111/jeu.12726] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Revised: 02/13/2019] [Accepted: 02/28/2019] [Indexed: 12/13/2022]
Affiliation(s)
- Kantima Janchot
- Department of Microbiology Faculty of Science Chulalongkorn University Pathumwan Bangkok 10330 Thailand
- The Chemical Approaches for Food Applications Research Group Faculty of Science Chulalongkorn University Pathumwan Bangkok 10330 Thailand
| | - Monrawat Rauytanapanit
- The Chemical Approaches for Food Applications Research Group Faculty of Science Chulalongkorn University Pathumwan Bangkok 10330 Thailand
- Department of Chemistry Faculty of Science Chulalongkorn University Pathumwan Bangkok 10330 Thailand
| | - Masaki Honda
- Department of Chemistry Faculty of Science and Technology Meijo University Nagoya 468‐8502 Japan
| | - Takashi Hibino
- Department of Chemistry Faculty of Science and Technology Meijo University Nagoya 468‐8502 Japan
- Graduate School of Environmental and Human Sciences Meijo University Nagoya 468‐8502 Japan
| | - Sophon Sirisattha
- Thailand Institute of Scientific and Technological Research (TISTR) Khlong Luang Pathum Thani 12120 Thailand
| | - Thanit Praneenararat
- The Chemical Approaches for Food Applications Research Group Faculty of Science Chulalongkorn University Pathumwan Bangkok 10330 Thailand
- Department of Chemistry Faculty of Science Chulalongkorn University Pathumwan Bangkok 10330 Thailand
| | - Hakuto Kageyama
- Department of Chemistry Faculty of Science and Technology Meijo University Nagoya 468‐8502 Japan
- Graduate School of Environmental and Human Sciences Meijo University Nagoya 468‐8502 Japan
| | - Rungaroon Waditee‐Sirisattha
- Department of Microbiology Faculty of Science Chulalongkorn University Pathumwan Bangkok 10330 Thailand
- The Chemical Approaches for Food Applications Research Group Faculty of Science Chulalongkorn University Pathumwan Bangkok 10330 Thailand
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Costa SS, Miranda AL, de Morais MG, Costa JAV, Druzian JI. Microalgae as source of polyhydroxyalkanoates (PHAs) - A review. Int J Biol Macromol 2019; 131:536-547. [PMID: 30885732 DOI: 10.1016/j.ijbiomac.2019.03.099] [Citation(s) in RCA: 66] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Revised: 03/10/2019] [Accepted: 03/15/2019] [Indexed: 01/09/2023]
Abstract
Polyhydroxyalkanoates (PHA) are biopolymers synthesized by different microorganisms and considered substitute powers for petroleum-based plastics because they have similar mechanical properties as synthetic polymers, can be processed in a similar way and are fully biodegradable. Currently commercial PHAs are produced in fermenters using bacteria and large amounts of organic carbon sources and salts in the culture media, accounting for approximately 50% of the total production costs. A greater commercial application of the PHA is limited to a decrease in the cost of production. Several studies suggest that microalgae are a type of microorganisms that can be used to obtain PHAs at a lower cost because they have minimum nutrient requirements for growth and are photoautotrophic in nature, i.e. they use light and CO2 as their main sources of energy. Thus, this work aims to provide a review on the production of PHAs of different microalgae, focusing on the properties and composition of biopolymers, verifying the potential of using these bioplastics instead of petroleum based plastics. Studies of stimulation PHA synthesis by microalgae are still considered incipient. Still, it is clear that microalgae have the potential to produce biopolymers with lower cost and can play a vital role in the environment.
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Affiliation(s)
- Samantha Serra Costa
- Institute of Health Sciences, RENORBIO, Federal University of Bahia, Salvador, Bahia, Brazil; Federal University of the Recôncavo of Bahia, Feira de Santana, Bahia, Brazil.
| | - Andréa Lobo Miranda
- Institute of Health Sciences, RENORBIO, Federal University of Bahia, Salvador, Bahia, Brazil; Federal Institute of Baiano, Santa Inês, Bahia, Brazil
| | - Michele Greque de Morais
- Laboratory of Biochemical Engineering, College of Chemistry and Food Engineering, Federal University of Rio Grande, Rio Grande, Brazil
| | - Jorge Alberto Vieira Costa
- Laboratory of Biochemical Engineering, College of Chemistry and Food Engineering, Federal University of Rio Grande, Rio Grande, Brazil
| | - Janice Izabel Druzian
- Department of Bromatological Analysis, College of Pharmacy, Federal University of Bahia, Salvador, Bahia, Brazil
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Sun D, Zhang Z, Zhang Y, Cheng KW, Chen F. Light induces carotenoids accumulation in a heterotrophic docosahexaenoic acid producing microalga, Crypthecodinium sp. SUN. BIORESOURCE TECHNOLOGY 2019; 276:177-182. [PMID: 30623873 DOI: 10.1016/j.biortech.2018.12.093] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Revised: 12/22/2018] [Accepted: 12/24/2018] [Indexed: 06/09/2023]
Abstract
In the present study, the effect of various light conditions on carotenoid accumulation in a novel heterotrophic microalga, Crypthecodinium sp. SUN was investigated. The results showed that C. sp. SUN mainly produced γ-carotene and β-carotene. The total carotenoid content could reach to 12.8 mg g-1 dry weight under high light intensity (100 μmol m-2 s-1), which was >100-fold higher than that under dark condition. Besides, along with the light intensity increased, the ROS level in vivo was decreased at 48 h and 72 h. Further study showed that, light could efficiently promote the gene expression of PSY and LCYb, which explain the molecular mechanisms of carotenoids accumulation under light conditions. Meanwhile, slightly inhibited fatty acids accumulation could promote the carotenoids yield. The present work proposed that C. sp. SUN could be a potential carotenoid producer, and provided valuable insight for carotenoids biosynthesis.
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Affiliation(s)
- Dongzhe Sun
- Institute for Food & Bioresource Engineering, College of Engineering, Peking University, Beijing 100871, China; Nutrition & Health Research Institute, COFCO, Beijing 102209, China
| | - Zhao Zhang
- Institute for Food & Bioresource Engineering, College of Engineering, Peking University, Beijing 100871, China; BIC-ESAT, College of Engineering, Peking University, Beijing 100871, China
| | - Yue Zhang
- BIC-ESAT, College of Engineering, Peking University, Beijing 100871, China
| | - Ka-Wing Cheng
- Institute for Food & Bioresource Engineering, College of Engineering, Peking University, Beijing 100871, China; BIC-ESAT, College of Engineering, Peking University, Beijing 100871, China; Institute for Advanced Study, Shenzhen University, Nanshan, Shenzhen 518060, China
| | - Feng Chen
- Institute for Food & Bioresource Engineering, College of Engineering, Peking University, Beijing 100871, China; BIC-ESAT, College of Engineering, Peking University, Beijing 100871, China; Institute for Advanced Study, Shenzhen University, Nanshan, Shenzhen 518060, China.
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Tamaki S, Kato S, Shinomura T, Ishikawa T, Imaishi H. Physiological role of β-carotene monohydroxylase (CYP97H1) in carotenoid biosynthesis in Euglena gracilis. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2019; 278:80-87. [PMID: 30471732 DOI: 10.1016/j.plantsci.2018.10.017] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Revised: 09/30/2018] [Accepted: 10/18/2018] [Indexed: 05/02/2023]
Abstract
Some carotenoids are found in the Euglena gracilis, including β-carotene, diadinoxanthin, diatoxanthins, and neoxanthin as the major species; however, the molecular mechanism underlying carotenoid biosynthesis in E. gracilis is not well understood. To clarify the pathway and regulation of carotenoid biosynthesis in this alga, we functionally characterized the cytochrome P450 (CYP)-type carotene hydroxylase gene EgCYP97H1. Heterologous in vivo enzyme assay in E. coli indicated that EgCYP97H1 hydroxylated β-carotene to β-cryptoxanthin. E. gracilis cells suppressing EgCYP97H1 resulted in marked growth inhibition and reductions in total carotenoid and chlorophyll contents. Analysis of carotenoid composition revealed that suppression of EgCYP97H1 resulted in higher level of β-carotene, suggesting that EgCYP97H1 is physiologically essential for carotenoid biosynthesis and thus normal cell growth. To our knowledge, this is the first time EgCYP97H1 has been suggested to be β-carotene monohydroxylase, but not β-carotene dihydroxylase. Moreover, during light adaptation of dark-grown E. gracilis, transcript levels of the carotenoid biosynthetic genes (EgCYP97H1, geranylgeranyl pyrophosphate synthase EgcrtE, and phytoene synthase EgcrtB) remained virtually unchanged. In contrast, carotenoid accumulation in E. gracilis grown under the same conditions was inhibited by treatment with a translational inhibitor but not a transcriptional inhibitor, indicating that photo-responsive carotenoid biosynthesis is regulated post-transcriptionally in this alga.
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Affiliation(s)
- Shun Tamaki
- Division of Signal Responses, Biosignal Research Center, Kobe University, 1-1 Rokkodai, Nada, Kobe, 657-8501, Japan
| | - Shota Kato
- Department of Biosciences, School of Science and Engineering, Teikyo University, 1-1 Toyosatodai, Utsunomiya, Tochigi, 320-8551, Japan
| | - Tomoko Shinomura
- Department of Biosciences, School of Science and Engineering, Teikyo University, 1-1 Toyosatodai, Utsunomiya, Tochigi, 320-8551, Japan
| | - Takahiro Ishikawa
- Faculty of Life and Environmental Science, Department of Life Science and Biotechnology, Shimane University, 1060 Nishikawatsu, Matsue, Shimane, 690-8504, Japan
| | - Hiromasa Imaishi
- Division of Signal Responses, Biosignal Research Center, Kobe University, 1-1 Rokkodai, Nada, Kobe, 657-8501, Japan.
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19
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Zhang Y, Shi M, Mao X, Kou Y, Liu J. Time-resolved carotenoid profiling and transcriptomic analysis reveal mechanism of carotenogenesis for astaxanthin synthesis in the oleaginous green alga Chromochloris zofingiensis. BIOTECHNOLOGY FOR BIOFUELS 2019; 12:287. [PMID: 31890015 PMCID: PMC6913025 DOI: 10.1186/s13068-019-1626-1] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Accepted: 12/04/2019] [Indexed: 05/03/2023]
Abstract
BACKGROUND Chromochloris zofingiensis is emerging as an industrially relevant alga given its robust growth for the production of lipids and astaxanthin, a value-added carotenoid with broad applications. Nevertheless, poor understanding of astaxanthin synthesis has limited engineering of this alga for rational improvements. RESULTS To reveal the molecular mechanism underlying astaxanthin accumulation in C. zofingiensis, here we conducted an integrated analysis by combining the time-resolved transcriptomes and carotenoid profiling in response to nitrogen deprivation (ND). A global response was triggered for C. zofingiensis to cope with the ND stress. Albeit the little variation in total carotenoid content, individual carotenoids responded differentially to ND: the primary carotenoids particularly lutein and β-carotene decreased, while the secondary carotenoids increased considerably, with astaxanthin and canthaxanthin being the most increased ones. The carotenogenesis pathways were reconstructed: ND had little effect on the carbon flux to carotenoid precursors, but stimulated astaxanthin biosynthesis while repressing lutein biosynthesis, thereby diverting the carotenoid flux from primary carotenoids to secondary carotenoids particularly astaxanthin. Comparison between C. zofingiensis and Haematococcus pluvialis revealed the distinctive mechanism of astaxanthin synthesis in C. zofingiensis. Furthermore, potential bottlenecks in astaxanthin synthesis were identified and possible engineering strategies were proposed for the alga. CONCLUSIONS Collectively, these findings shed light on distinctive mechanism of carotenogenesis for astaxanthin biosynthesis in C. zofingiensis, identify key functional enzymes and regulators with engineering potential and will benefit rational manipulation of this alga for improving nutritional traits.
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Affiliation(s)
- Yu Zhang
- Laboratory for Algae Biotechnology & Innovation, College of Engineering, Peking University, Beijing, 100871 China
| | - Meicheng Shi
- Laboratory for Algae Biotechnology & Innovation, College of Engineering, Peking University, Beijing, 100871 China
| | - Xuemei Mao
- Laboratory for Algae Biotechnology & Innovation, College of Engineering, Peking University, Beijing, 100871 China
| | - Yaping Kou
- Laboratory for Algae Biotechnology & Innovation, College of Engineering, Peking University, Beijing, 100871 China
| | - Jin Liu
- Laboratory for Algae Biotechnology & Innovation, College of Engineering, Peking University, Beijing, 100871 China
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Biological characterization of a strain of Golenkinia (Chlorophyceae) with high oil and carotenoid content induced by increased salinity. ALGAL RES 2018. [DOI: 10.1016/j.algal.2018.05.014] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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21
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Guyon JB, Vergé V, Schatt P, Lozano JC, Liennard M, Bouget FY. Comparative Analysis of Culture Conditions for the Optimization of Carotenoid Production in Several Strains of the Picoeukaryote Ostreococcus. Mar Drugs 2018; 16:md16030076. [PMID: 29495580 PMCID: PMC5867620 DOI: 10.3390/md16030076] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Revised: 02/16/2018] [Accepted: 02/16/2018] [Indexed: 01/09/2023] Open
Abstract
Microalgae are promising sources for the sustainable production of compounds of interest for biotechnologies. Compared to higher plants, microalgae have a faster growth rate and can be grown in industrial photobioreactors. The microalgae biomass contains specific metabolites of high added value for biotechnology such as lipids, polysaccharides or carotenoid pigments. Studying carotenogenesis is important for deciphering the mechanisms of adaptation to stress tolerance as well as for biotechnological production. In recent years, the picoeukaryote Ostreococcustauri has emerged as a model organism thanks to the development of powerful genetic tools. Several strains of Ostreococcus isolated from different environments have been characterized with respect to light response or iron requirement. We have compared the carotenoid contents and growth rates of strains of Ostreococcus (OTTH595, RCC802 and RCC809) under a wide range of light, salinity and temperature conditions. Carotenoid profiles and productivities varied in a strain-specific and stress-dependent manner. Our results also illustrate that phylogenetically related microalgal strains originating from different ecological niches present specific interests for the production of specific molecules under controlled culture conditions.
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Affiliation(s)
- Jean-Baptiste Guyon
- Observatoire Océanologique, UMR 7621 Laboratoire d'Océanographie Microbienne, Université de Pierre et Marie Curie (Paris 06), Sorbonne Universités, 66650 Banyuls-sur-Mer, France.
| | - Valérie Vergé
- Observatoire Océanologique, UMR 7621 Laboratoire d'Océanographie Microbienne, Université de Pierre et Marie Curie (Paris 06), Sorbonne Universités, 66650 Banyuls-sur-Mer, France.
| | - Philippe Schatt
- Observatoire Océanologique, UMR 7621 Laboratoire d'Océanographie Microbienne, Université de Pierre et Marie Curie (Paris 06), Sorbonne Universités, 66650 Banyuls-sur-Mer, France.
| | - Jean-Claude Lozano
- Observatoire Océanologique, UMR 7621 Laboratoire d'Océanographie Microbienne, Université de Pierre et Marie Curie (Paris 06), Sorbonne Universités, 66650 Banyuls-sur-Mer, France.
| | - Marion Liennard
- Observatoire Océanologique, UMR 7621 Laboratoire d'Océanographie Microbienne, Université de Pierre et Marie Curie (Paris 06), Sorbonne Universités, 66650 Banyuls-sur-Mer, France.
| | - François-Yves Bouget
- Observatoire Océanologique, UMR 7621 Laboratoire d'Océanographie Microbienne, Université de Pierre et Marie Curie (Paris 06), Sorbonne Universités, 66650 Banyuls-sur-Mer, France.
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Mao X, Wu T, Sun D, Zhang Z, Chen F. Differential responses of the green microalga Chlorella zofingiensis to the starvation of various nutrients for oil and astaxanthin production. BIORESOURCE TECHNOLOGY 2018; 249:791-798. [PMID: 29136934 DOI: 10.1016/j.biortech.2017.10.090] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Revised: 10/25/2017] [Accepted: 10/26/2017] [Indexed: 05/03/2023]
Abstract
Chlorella zofingiensis has been proposed as a potential producer of lipids and the high-value carotenoid astaxanthin. In this study, the responses of photoautotrophic C. zofingiensis with respect to growth, lipid profiles and astaxanthin accumulation were investigated upon the starvation of N (NS), P (PS) and S (SS). NS and SS stimulated triacylglycerol (TAG) accumulation, which reached 27% and 21% of dry weight (DW), respectively. Stresses also stimulated astaxanthin accumulation greatly, reaching 3.9 mg/g DW by NS. SS led to the highest TAG productivity (52.4 mg L-1 d-1) while NS gave rise to the highest astaxanthin productivity (0.624 mg L-1 d-1). In combination with transcriptional analysis, a working model for stress-associated TAG and astaxanthin biosynthesis was proposed. Taken together, these detailed data shed light on the elucidation of differential responses to nutrient stresses and may provide insights into future engineering of this promising alga for improving TAG and astaxanthin production.
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Affiliation(s)
- Xuemei Mao
- Institute for Food and Bioresource Engineering, College of Engineering, Peking University, Beijing 100871, China; BIC-ESAT, College of Engineering, Peking University, Beijing 100871, China
| | - Tao Wu
- Institute for Food and Bioresource Engineering, College of Engineering, Peking University, Beijing 100871, China; BIC-ESAT, College of Engineering, Peking University, Beijing 100871, China
| | - Dongzhe Sun
- Institute for Food and Bioresource Engineering, College of Engineering, Peking University, Beijing 100871, China; BIC-ESAT, College of Engineering, Peking University, Beijing 100871, China
| | - Zhao Zhang
- Institute for Food and Bioresource Engineering, College of Engineering, Peking University, Beijing 100871, China; BIC-ESAT, College of Engineering, Peking University, Beijing 100871, China
| | - Feng Chen
- Institute for Food and Bioresource Engineering, College of Engineering, Peking University, Beijing 100871, China; BIC-ESAT, College of Engineering, Peking University, Beijing 100871, China.
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Huang W, Lin Y, He M, Gong Y, Huang J. Induced High-Yield Production of Zeaxanthin, Lutein, and β-Carotene by a Mutant of Chlorella zofingiensis. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2018; 66:891-897. [PMID: 29319312 DOI: 10.1021/acs.jafc.7b05400] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Natural resources of zeaxanthin are extremely limited. A Chlorella zofingiensis mutant (CZ-bkt1), which could accumulate high amounts of zeaxanthin, was generated and characterized. CZ-bkt1 was achieved by treating the algal cells with a chemical mutagen followed by a color-based colony-screening approach. CZ-bkt1 was found to consist of a dysfunctional carotenoid ketolase, leading to the accumulation of zeaxanthin rather than to its downstream ketocarotenoid astaxanthin. Light irradiation, glucose, NaCl, and nitrogen deficiency all induced CZ-bkt1 to accumulate zeaxanthin. CZ-bkt1 accumulated zeaxanthin up to 7.00 ± 0.82 mg/g when induced by high-light irradiation and nitrogen deficiency and up to 36.79 ± 2.23 mg/L by additional feeding with glucose. Furthermore, in addition to zeaxanthin, CZ-bkt1 also accumulated high amounts of β-carotene (7.18 ± 0.72 mg/g or 34.64 ± 1.39 mg/L) and lutein (13.81 ± 1.23 mg/g or 33.97 ± 2.61 mg/L). CZ-bkt1 is the sole species up to date with the ability to accumulate high amounts of the three carotenoids that are essential for human health.
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Affiliation(s)
- Weiping Huang
- Department of Economic Plants and Biotechnology, Yunnan Key Laboratory for Wild Plant Resources, Kunming Institute of Botany, Chinese Academy of Sciences , Kunming 650201, China
| | - Yan Lin
- Department of Economic Plants and Biotechnology, Yunnan Key Laboratory for Wild Plant Resources, Kunming Institute of Botany, Chinese Academy of Sciences , Kunming 650201, China
| | - Mingxia He
- Department of Economic Plants and Biotechnology, Yunnan Key Laboratory for Wild Plant Resources, Kunming Institute of Botany, Chinese Academy of Sciences , Kunming 650201, China
| | - Yuhao Gong
- Department of Economic Plants and Biotechnology, Yunnan Key Laboratory for Wild Plant Resources, Kunming Institute of Botany, Chinese Academy of Sciences , Kunming 650201, China
| | - Junchao Huang
- Department of Economic Plants and Biotechnology, Yunnan Key Laboratory for Wild Plant Resources, Kunming Institute of Botany, Chinese Academy of Sciences , Kunming 650201, China
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Paliwal C, Mitra M, Bhayani K, Bharadwaj SVV, Ghosh T, Dubey S, Mishra S. Abiotic stresses as tools for metabolites in microalgae. BIORESOURCE TECHNOLOGY 2017; 244:1216-1226. [PMID: 28552566 DOI: 10.1016/j.biortech.2017.05.058] [Citation(s) in RCA: 138] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Revised: 05/08/2017] [Accepted: 05/10/2017] [Indexed: 05/28/2023]
Abstract
Microalgae, due to various environmental stresses, constantly tune their cellular mechanisms to cope with them. The accumulation of the stress metabolites is closely related to the changes occurring in their metabolic pathways. The biosynthesis of metabolites can be triggered by a number of abiotic stresses like temperature, salinity, UV- radiation and nutrient deprivation. Although, microalgae have been considered as an alternative sustainable source for nutraceutical products like pigments and omega-3 polyunsaturated fatty acids (PUFAs) to cater the requirement of emerging human population but inadequate biomass generation makes the process economically impractical. The stress metabolism for carotenoid regulation in green algae is a 2-step metabolism. There are a few major stresses which can influence the formation of phycobiliprotein in cyanobacteria. This review would primarily focus on the cellular level changes under stress conditions and their corresponding effects on lipids (including omega-3 PUFAs), pigments and polymers.
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Affiliation(s)
- Chetan Paliwal
- Salt and Marine Chemicals Division, CSIR-Central Salt & Marine Chemicals Research Institute, Gijubhai Badheka Marg, Bhavnagar 364002, Gujarat, India; Academy of Scientific and Innovative Research, AcSIR-CSMCRI, Gijubhai Badheka Marg, Bhavnagar 364002, Gujarat, India
| | - Madhusree Mitra
- Salt and Marine Chemicals Division, CSIR-Central Salt & Marine Chemicals Research Institute, Gijubhai Badheka Marg, Bhavnagar 364002, Gujarat, India; Academy of Scientific and Innovative Research, AcSIR-CSMCRI, Gijubhai Badheka Marg, Bhavnagar 364002, Gujarat, India
| | - Khushbu Bhayani
- Salt and Marine Chemicals Division, CSIR-Central Salt & Marine Chemicals Research Institute, Gijubhai Badheka Marg, Bhavnagar 364002, Gujarat, India
| | - S V Vamsi Bharadwaj
- Salt and Marine Chemicals Division, CSIR-Central Salt & Marine Chemicals Research Institute, Gijubhai Badheka Marg, Bhavnagar 364002, Gujarat, India; Academy of Scientific and Innovative Research, AcSIR-CSMCRI, Gijubhai Badheka Marg, Bhavnagar 364002, Gujarat, India
| | - Tonmoy Ghosh
- Salt and Marine Chemicals Division, CSIR-Central Salt & Marine Chemicals Research Institute, Gijubhai Badheka Marg, Bhavnagar 364002, Gujarat, India; Academy of Scientific and Innovative Research, AcSIR-CSMCRI, Gijubhai Badheka Marg, Bhavnagar 364002, Gujarat, India
| | - Sonam Dubey
- Salt and Marine Chemicals Division, CSIR-Central Salt & Marine Chemicals Research Institute, Gijubhai Badheka Marg, Bhavnagar 364002, Gujarat, India
| | - Sandhya Mishra
- Salt and Marine Chemicals Division, CSIR-Central Salt & Marine Chemicals Research Institute, Gijubhai Badheka Marg, Bhavnagar 364002, Gujarat, India; Academy of Scientific and Innovative Research, AcSIR-CSMCRI, Gijubhai Badheka Marg, Bhavnagar 364002, Gujarat, India.
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Kato S, Soshino M, Takaichi S, Ishikawa T, Nagata N, Asahina M, Shinomura T. Suppression of the phytoene synthase gene (EgcrtB) alters carotenoid content and intracellular structure of Euglena gracilis. BMC PLANT BIOLOGY 2017; 17:125. [PMID: 28716091 PMCID: PMC5513367 DOI: 10.1186/s12870-017-1066-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Accepted: 06/23/2017] [Indexed: 05/02/2023]
Abstract
BACKGROUND Photosynthetic organisms utilize carotenoids for photoprotection as well as light harvesting. Our previous study revealed that high-intensity light increases the expression of the gene for phytoene synthase (EgcrtB) in Euglena gracilis (a unicellular phytoflagellate), the encoded enzyme catalyzes the first committed step of the carotenoid biosynthesis pathway. To examine carotenoid synthesis of E. gracilis in response to light stress, we analyzed carotenoid species and content in cells grown under various light intensities. In addition, we investigated the effect of suppressing EgcrtB with RNA interference (RNAi) on growth and carotenoid content. RESULTS After cultivation for 7 days under continuous light at 920 μmol m-2 s-1, β-carotene, diadinoxanthin (Ddx), and diatoxanthin (Dtx) content in cells was significantly increased compared with standard light intensity (55 μmol m-2 s-1). The high-intensity light (920 μmol m-2 s-1) increased the pool size of diadinoxanthin cycle pigments (i.e., Ddx + Dtx) by 1.2-fold and the Dtx/Ddx ratio from 0.05 (control) to 0.09. In contrast, the higher-intensity light treatment caused a 58% decrease in chlorophyll (a + b) content and diminished the number of thylakoid membranes in chloroplasts by approximately half compared with control cells, suggesting that the high-intensity light-induced accumulation of carotenoids is associated with an increase in both the number and size of lipid globules in chloroplasts and the cytoplasm. Transient suppression of EgcrtB in this alga by RNAi resulted in significant decreases in cell number, chlorophyll, and total major carotenoid content by 82, 82 and 86%, respectively, relative to non-electroporated cells. Furthermore, suppression of EgcrtB decreased the number of chloroplasts and thylakoid membranes and increased the Dtx/Ddx ratio by 1.6-fold under continuous illumination even at the standard light intensity, indicating that blocking carotenoid synthesis increased the susceptibility of cells to light stress. CONCLUSIONS Our results indicate that suppression of EgcrtB causes a significant decrease in carotenoid and chlorophyll content in E. gracilis accompanied by changes in intracellular structures, suggesting that Dtx (de-epoxidized form of diadinoxanthin cycle pigments) contributes to photoprotection of this alga during the long-term acclimation to light-induced stress.
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Affiliation(s)
- Shota Kato
- Department of Biosciences, School of Science and Engineering, Teikyo University, 1-1 Toyosatodai, Utsunomiya, Tochigi 320-8551 Japan
- Plant Molecular and Cellular Biology Laboratory, Department of Biosciences, School of Science and Engineering, Teikyo University, 1-1 Toyosatodai, Utsunomiya, Tochigi 320-8551 Japan
| | - Mika Soshino
- Plant Molecular and Cellular Biology Laboratory, Graduate School of Science and Engineering, Teikyo University, 1-1 Toyosatodai, Utsunomiya, Tochigi 320-8551 Japan
| | - Shinichi Takaichi
- Department of Biology, Nippon Medical School, 1-7-1 Kyonan-cho, Musashino, Tokyo 180-0023 Japan
- Department of Molecular Microbiology, Faculty of Life Sciences, Tokyo University of Agriculture, 1-1-1 Sakuragaoka, Setagaya, Tokyo 156-8502 Japan
| | - Takahiro Ishikawa
- Department of Life Science and Biotechnology, Faculty of Life and Environmental Science, Shimane University, 1060 Nishikawatsu, Matsue, Shimane 690-8504 Japan
| | - Noriko Nagata
- Faculty of Science, Japan Women’s University, Bunkyo-ku, Tokyo, 112-8681 Japan
| | - Masashi Asahina
- Department of Biosciences, School of Science and Engineering, Teikyo University, 1-1 Toyosatodai, Utsunomiya, Tochigi 320-8551 Japan
| | - Tomoko Shinomura
- Department of Biosciences, School of Science and Engineering, Teikyo University, 1-1 Toyosatodai, Utsunomiya, Tochigi 320-8551 Japan
- Plant Molecular and Cellular Biology Laboratory, Department of Biosciences, School of Science and Engineering, Teikyo University, 1-1 Toyosatodai, Utsunomiya, Tochigi 320-8551 Japan
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Chromosome-level genome assembly and transcriptome of the green alga Chromochloris zofingiensis illuminates astaxanthin production. Proc Natl Acad Sci U S A 2017; 114:E4296-E4305. [PMID: 28484037 PMCID: PMC5448231 DOI: 10.1073/pnas.1619928114] [Citation(s) in RCA: 100] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Microalgae have potential to help meet energy and food demands without exacerbating environmental problems. There is interest in the unicellular green alga Chromochloris zofingiensis, because it produces lipids for biofuels and a highly valuable carotenoid nutraceutical, astaxanthin. To advance understanding of its biology and facilitate commercial development, we present a C. zofingiensis chromosome-level nuclear genome, organelle genomes, and transcriptome from diverse growth conditions. The assembly, derived from a combination of short- and long-read sequencing in conjunction with optical mapping, revealed a compact genome of ∼58 Mbp distributed over 19 chromosomes containing 15,274 predicted protein-coding genes. The genome has uniform gene density over chromosomes, low repetitive sequence content (∼6%), and a high fraction of protein-coding sequence (∼39%) with relatively long coding exons and few coding introns. Functional annotation of gene models identified orthologous families for the majority (∼73%) of genes. Synteny analysis uncovered localized but scrambled blocks of genes in putative orthologous relationships with other green algae. Two genes encoding beta-ketolase (BKT), the key enzyme synthesizing astaxanthin, were found in the genome, and both were up-regulated by high light. Isolation and molecular analysis of astaxanthin-deficient mutants showed that BKT1 is required for the production of astaxanthin. Moreover, the transcriptome under high light exposure revealed candidate genes that could be involved in critical yet missing steps of astaxanthin biosynthesis, including ABC transporters, cytochrome P450 enzymes, and an acyltransferase. The high-quality genome and transcriptome provide insight into the green algal lineage and carotenoid production.
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Zhang Z, Huang JJ, Sun D, Lee Y, Chen F. Two-step cultivation for production of astaxanthin in Chlorella zofingiensis using a patented energy-free rotating floating photobioreactor (RFP). BIORESOURCE TECHNOLOGY 2017; 224:515-522. [PMID: 27818161 DOI: 10.1016/j.biortech.2016.10.081] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2016] [Revised: 10/25/2016] [Accepted: 10/26/2016] [Indexed: 05/03/2023]
Abstract
In the present study, high light and nitrogen starvation with glucose-fed to the culture was found efficient to induce astaxanthin accumulation in Chlorella zofingiensis. Therefore, a two-step cultivation strategy including high biomass yield fermentation and outdoor induction with an energy-free RFP was conducted. During the fermentation, the highest cell density of 98.4gL-1 and astaxanthin yield of 73.3mgL-1 were achieved, which were higher than those so far reported in C. zofingiensis. During the outdoor induction, astaxanthin content was further increased by 1.5-fold leading to the highest astaxanthin productivity of 5.26mgL-1day-1 under an optimal dilution of 5-fold. Our work thus provided an effective two-step cultivation strategy for production of astaxanthin by C. zofingiensis.
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Affiliation(s)
- Zhao Zhang
- Institute for Food & Bioresource Engineering, College of Engineering, Peking University, Beijing 100871, China; Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, 5 Science Drive 2, Singapore 117597, Singapore; BIC-ESAT, College of Engineering, Peking University, Beijing 100871, China
| | - Jim Junhui Huang
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, 5 Science Drive 2, Singapore 117597, Singapore
| | - Dongzhe Sun
- Institute for Food & Bioresource Engineering, College of Engineering, Peking University, Beijing 100871, China; Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, 5 Science Drive 2, Singapore 117597, Singapore; BIC-ESAT, College of Engineering, Peking University, Beijing 100871, China
| | - Yuankun Lee
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, 5 Science Drive 2, Singapore 117597, Singapore
| | - Feng Chen
- Institute for Food & Bioresource Engineering, College of Engineering, Peking University, Beijing 100871, China; BIC-ESAT, College of Engineering, Peking University, Beijing 100871, China.
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Huang W, Ye J, Zhang J, Lin Y, He M, Huang J. Transcriptome analysis of Chlorella zofingiensis to identify genes and their expressions involved in astaxanthin and triacylglycerol biosynthesis. ALGAL RES 2016. [DOI: 10.1016/j.algal.2016.05.015] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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Benavente-Valdés JR, Aguilar C, Contreras-Esquivel JC, Méndez-Zavala A, Montañez J. Strategies to enhance the production of photosynthetic pigments and lipids in chlorophycae species. ACTA ACUST UNITED AC 2016; 10:117-125. [PMID: 28352532 PMCID: PMC5040869 DOI: 10.1016/j.btre.2016.04.001] [Citation(s) in RCA: 85] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2015] [Revised: 03/16/2016] [Accepted: 04/02/2016] [Indexed: 11/25/2022]
Abstract
Microalgae are source of valuable compounds as lipids, proteins, carbohydrates, pigments among others. Culture stress conditions increase biomass and high values compounds in microalgae. Nitrogen and salt stress increase lipids in microalgae. Two stages culture and electromagnetic fields enhancing microalgae biomass and pigments content.
Microalgae are a major natural source for a vast array of valuable compounds as lipids, proteins, carbohydrates, pigments among others. Despite many applications, only a few species of microalgae are cultured commercially because of poorly developed of cultivation process. Nowadays some strategies of culture have been used for enhancing biomass and value compounds yield. The most strategies applied to microalgae are classified into two groups: nutrimental and physical. The nutrimental are considered as change in media composition as nitrogen and phosphorous limitation and changes in carbon source, while physical are described as manipulation in operational conditions and external factors such as application of high-light intensities, medium salinity and electromagnetic fields. The exposition to electromagnetic field is a promising technique that can improve the pigments and biomass yield in microalgae culture. Therefore, is important to describe the advantages and applications of the overall process. The aim of this review was to describe the main culture strategies used to improve the photosynthetic and lipids content in chlorophyceae species.
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Affiliation(s)
- Juan Roberto Benavente-Valdés
- Department of Food Research, Universidad Autónoma de Coahuila, Universidad Autónoma de Coahuila, Saltillo, Coahuila, Mexico
| | - Cristóbal Aguilar
- Department of Food Research, Universidad Autónoma de Coahuila, Universidad Autónoma de Coahuila, Saltillo, Coahuila, Mexico
| | - Juan Carlos Contreras-Esquivel
- Department of Food Research, Universidad Autónoma de Coahuila, Universidad Autónoma de Coahuila, Saltillo, Coahuila, Mexico
| | - Alejandro Méndez-Zavala
- Department of Chemical Engineering, Universidad Autónoma de Coahuila, Universidad Autónoma de Coahuila, Saltillo, Coahuila, Mexico
| | - Julio Montañez
- Department of Chemical Engineering, Universidad Autónoma de Coahuila, Universidad Autónoma de Coahuila, Saltillo, Coahuila, Mexico
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Guihéneuf F, Khan A, Tran LSP. Genetic Engineering: A Promising Tool to Engender Physiological, Biochemical, and Molecular Stress Resilience in Green Microalgae. FRONTIERS IN PLANT SCIENCE 2016; 7:400. [PMID: 27066043 PMCID: PMC4815356 DOI: 10.3389/fpls.2016.00400] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Accepted: 03/14/2016] [Indexed: 05/03/2023]
Abstract
As we march into the 21st century, the prevailing scenario of depleting energy resources, global warming and ever increasing issues of human health and food security will quadruple. In this context, genetic and metabolic engineering of green microalgae complete the quest toward a continuum of environmentally clean fuel and food production. Evolutionarily related, but unlike land plants, microalgae need nominal land or water, and are best described as unicellular autotrophs using light energy to fix atmospheric carbon dioxide (CO2) into algal biomass, mitigating fossil CO2 pollution in the process. Remarkably, a feature innate to most microalgae is synthesis and accumulation of lipids (60-65% of dry weight), carbohydrates and secondary metabolites like pigments and vitamins, especially when grown under abiotic stress conditions. Particularly fruitful, such an application of abiotic stress factors such as nitrogen starvation, salinity, heat shock, etc., can be used in a biorefinery concept for production of multiple valuable products. The focus of this mini-review underlies metabolic reorientation practices and tolerance mechanisms as applied to green microalgae under specific stress stimuli for a sustainable pollution-free future. Moreover, we entail current progress on genetic engineering as a promising tool to grasp adaptive processes for improving strains with potential biotechnological interests.
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Affiliation(s)
- Freddy Guihéneuf
- Botany and Plant Science, School of Natural Sciences, Ryan Institute, National University of Ireland GalwayGalway, Ireland
| | - Asif Khan
- Research Group Germline Biology, Centre for Organismal Studies (COS), Heidelberg UniversityHeidelberg, Germany
| | - Lam-Son P. Tran
- Plant Abiotic Stress Research Group & Faculty of Applied Sciences, Ton Duc Thang UniversityHo Chi Minh City, Vietnam
- Signaling Pathway Research Unit, RIKEN Center for Sustainable Resource ScienceTsurumi, Japan
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Kato S, Takaichi S, Ishikawa T, Asahina M, Takahashi S, Shinomura T. Identification and functional analysis of the geranylgeranyl pyrophosphate synthase gene (crtE) and phytoene synthase gene (crtB) for carotenoid biosynthesis in Euglena gracilis. BMC PLANT BIOLOGY 2016; 16:4. [PMID: 26733341 PMCID: PMC4702402 DOI: 10.1186/s12870-015-0698-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Accepted: 12/21/2015] [Indexed: 05/02/2023]
Abstract
BACKGROUND Euglena gracilis, a unicellular phytoflagellate within Euglenida, has attracted much attention as a potential feedstock for renewable energy production. In outdoor open-pond cultivation for biofuel production, excess direct sunlight can inhibit photosynthesis in this alga and decrease its productivity. Carotenoids play important roles in light harvesting during photosynthesis and offer photoprotection for certain non-photosynthetic and photosynthetic organisms including cyanobacteria, algae, and higher plants. Although, Euglenida contains β-carotene and xanthophylls (such as zeaxanthin, diatoxanthin, diadinoxanthin and 9'-cis neoxanthin), the pathway of carotenoid biosynthesis has not been elucidated. RESULTS To clarify the carotenoid biosynthetic pathway in E. gracilis, we searched for the putative E. gracilis geranylgeranyl pyrophosphate (GGPP) synthase gene (crtE) and phytoene synthase gene (crtB) by tblastn searches from RNA-seq data and obtained their cDNAs. Complementation experiments in Escherichia coli with carotenoid biosynthetic genes of Pantoea ananatis showed that E. gracilis crtE (EgcrtE) and EgcrtB cDNAs encode GGPP synthase and phytoene synthase, respectively. Phylogenetic analyses indicated that the predicted proteins of EgcrtE and EgcrtB belong to a clade distinct from a group of GGPP synthase and phytoene synthase proteins, respectively, of algae and higher plants. In addition, we investigated the effects of light stress on the expression of crtE and crtB in E. gracilis. Continuous illumination at 460 or 920 μmol m(-2) s(-1) at 25 °C decreased the E. gracilis cell concentration by 28-40 % and 13-91 %, respectively, relative to the control light intensity (55 μmol m(-2) s(-1)). When grown under continuous light at 920 μmol m(-2) s(-1), the algal cells turned reddish-orange and showed a 1.3-fold increase in the crtB expression. In contrast, EgcrtE expression was not significantly affected by the light-stress treatments examined. CONCLUSIONS We identified genes encoding CrtE and CrtB in E. gracilis and found that their protein products catalyze the early steps of carotenoid biosynthesis. Further, we found that the response of the carotenoid biosynthetic pathway to light stress in E. gracilis is controlled, at least in part, by the level of crtB transcription. This is the first functional analysis of crtE and crtB in Euglena.
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Affiliation(s)
- Shota Kato
- Department of Biosciences, School of Science and Engineering, Teikyo University, 1-1 Toyosatodai, Utsunomiya, Tochigi, 320-8551, Japan.
- Plant Molecular and Cellular Biology Laboratory, Department of Biosciences, School of Science and Engineering, Teikyo University, 1-1 Toyosatodai, Utsunomiya, Tochigi, 320-8551, Japan.
| | - Shinichi Takaichi
- Department of Biology, Nippon Medical School, 1-7-1 Kyonan-cho, Musashino, Tokyo, 180-0023, Japan.
| | - Takahiro Ishikawa
- Department of Life Science and Biotechnology, Faculty of Life and Environmental Science, Shimane University, 1060 Nishikawatsu, Matsue, Shimane, 690-8504, Japan.
| | - Masashi Asahina
- Department of Biosciences, School of Science and Engineering, Teikyo University, 1-1 Toyosatodai, Utsunomiya, Tochigi, 320-8551, Japan.
| | - Senji Takahashi
- Department of Biosciences, School of Science and Engineering, Teikyo University, 1-1 Toyosatodai, Utsunomiya, Tochigi, 320-8551, Japan.
| | - Tomoko Shinomura
- Department of Biosciences, School of Science and Engineering, Teikyo University, 1-1 Toyosatodai, Utsunomiya, Tochigi, 320-8551, Japan.
- Plant Molecular and Cellular Biology Laboratory, Department of Biosciences, School of Science and Engineering, Teikyo University, 1-1 Toyosatodai, Utsunomiya, Tochigi, 320-8551, Japan.
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Abstract
Carotenoids are a class of isoprenoids synthesized by all photosynthetic organisms as well as by some non-photosynthetic bacteria and fungi with broad applications in food, feed and cosmetics, and also in the nutraceutical and pharmaceutical industries. Microalgae represent an important source of high-value products, which include carotenoids, among others. Carotenoids play key roles in light harvesting and energy transfer during photosynthesis and in the protection of the photosynthetic apparatus against photooxidative damage. Carotenoids are generally divided into carotenes and xanthophyls, but accumulation in microalgae can also be classified as primary (essential for survival) and secondary (by exposure to specific stimuli).In this chapter, we outline the high value carotenoids produced by commercially important microalgae, their production pathways, the improved production rates that can be achieved by genetic engineering as well as their biotechnological applications.
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Affiliation(s)
- Vitalia Henríquez
- Instituto de Biología, Facultad de Ciencias, Pontificia Universidad Católica de Valparaíso-Campus Curauma, Av. Universidad 330, Valparaíso, Chile.
| | - Carolina Escobar
- Instituto de Biología, Facultad de Ciencias, Pontificia Universidad Católica de Valparaíso-Campus Curauma, Av. Universidad 330, Valparaíso, Chile
| | - Janeth Galarza
- Instituto de Biología, Facultad de Ciencias, Pontificia Universidad Católica de Valparaíso-Campus Curauma, Av. Universidad 330, Valparaíso, Chile
| | - Javier Gimpel
- Instituto de Biología, Facultad de Ciencias, Pontificia Universidad Católica de Valparaíso-Campus Curauma, Av. Universidad 330, Valparaíso, Chile
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Hong ME, Choi YY, Sim SJ. Effect of red cyst cell inoculation and iron(II) supplementation on autotrophic astaxanthin production by Haematococcus pluvialis under outdoor summer conditions. J Biotechnol 2016; 218:25-33. [DOI: 10.1016/j.jbiotec.2015.11.019] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Revised: 11/02/2015] [Accepted: 11/24/2015] [Indexed: 11/26/2022]
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Enhanced autotrophic astaxanthin production from Haematococcus pluvialis under high temperature via heat stress-driven Haber-Weiss reaction. Appl Microbiol Biotechnol 2015; 99:5203-15. [PMID: 25683663 DOI: 10.1007/s00253-015-6440-5] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Revised: 01/20/2015] [Accepted: 01/26/2015] [Indexed: 10/24/2022]
Abstract
High temperatures (30-36 °C) inhibited astaxanthin accumulation in Haematococcus pluvialis under photoautotrophic conditions. The depression of carotenogenesis was primarily attributed to excess intracellular less reactive oxygen species (LROS; O2 (-) and H2O2) levels generated under high temperature conditions. Here, we show that the heat stress-driven inefficient astaxanthin production was improved by accelerating the iron-catalyzed Haber-Weiss reaction to convert LROS into more reactive oxygen species (MROS; O2 and OH·), thereby facilitating lipid peroxidation. As a result, during 18 days of photoautotrophic induction, the astaxanthin concentration of cells cultured in high temperatures in the presence of iron (450 μM) was dramatically increased by 75 % (30 °C) and 133 % (36 °C) compared to that of cells exposed to heat stress alone. The heat stress-driven Haber-Weiss reaction will be useful for economically producing astaxanthin by reducing energy cost and enhancing photoautotrophic astaxanthin production, particularly outdoors utilizing natural solar radiation including heat and light for photo-induction of H. pluvialis.
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Gene cloning, sequence analysis, and expression profiles of a novel β-ring carotenoid hydroxylase gene from the photoheterotrophic green alga Chlorella kessleri. Mol Biol Rep 2014; 41:7103-13. [DOI: 10.1007/s11033-014-3524-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2013] [Accepted: 06/19/2014] [Indexed: 10/24/2022]
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Liu J, Sun Z, Gerken H, Liu Z, Jiang Y, Chen F. Chlorella zofingiensis as an alternative microalgal producer of astaxanthin: biology and industrial potential. Mar Drugs 2014; 12:3487-515. [PMID: 24918452 PMCID: PMC4071588 DOI: 10.3390/md12063487] [Citation(s) in RCA: 142] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2014] [Revised: 05/18/2014] [Accepted: 05/20/2014] [Indexed: 01/01/2023] Open
Abstract
Astaxanthin (3,3'-dihydroxy-β,β-carotene-4,4'-dione), a high-value ketocarotenoid with a broad range of applications in food, feed, nutraceutical, and pharmaceutical industries, has been gaining great attention from science and the public in recent years. The green microalgae Haematococcus pluvialis and Chlorella zofingiensis represent the most promising producers of natural astaxanthin. Although H. pluvialis possesses the highest intracellular astaxanthin content and is now believed to be a good producer of astaxanthin, it has intrinsic shortcomings such as slow growth rate, low biomass yield, and a high light requirement. In contrast, C. zofingiensis grows fast phototrophically, heterotrophically and mixtrophically, is easy to be cultured and scaled up both indoors and outdoors, and can achieve ultrahigh cell densities. These robust biotechnological traits provide C. zofingiensis with high potential to be a better organism than H. pluvialis for mass astaxanthin production. This review aims to provide an overview of the biology and industrial potential of C. zofingiensis as an alternative astaxanthin producer. The path forward for further expansion of the astaxanthin production from C. zofingiensis with respect to both challenges and opportunities is also discussed.
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Affiliation(s)
- Jin Liu
- Institute for Food & Bioresource Engineering, College of Engineering, Peking University, Beijing 100871, China.
| | - Zheng Sun
- College of Fisheries and Life Science, Shanghai Ocean University, Shanghai 201306, China.
| | - Henri Gerken
- Department of Applied Sciences and Mathematics, Arizona State University Polytechnic campus, Mesa, AZ 85212, USA.
| | - Zheng Liu
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032, USA.
| | - Yue Jiang
- School of Food Science, Jiangnan University, Wuxi 214122, China.
| | - Feng Chen
- Institute for Food & Bioresource Engineering, College of Engineering, Peking University, Beijing 100871, China.
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Establishing oleaginous microalgae research models for consolidated bioprocessing of solar energy. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2014; 128:69-84. [PMID: 22089825 DOI: 10.1007/10_2011_122] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
Algal feedstock is the foundation of the emerging algal biofuel industry. However, few algae found in nature have demonstrated the combination of high biomass accumulation rate, robust oil yield and tolerance to environmental stresses, all complex traits that a large-scale, economically competitive production scheme demands. Therefore, untangling the intricate sub-cellular networks underlying these complex traits, in one or a series of carefully selected algal research models, has become an urgent research mission, which can take advantage of the emerging model oleaginous microalgae that have already demonstrated small, simple and tackleable genomes and the potential for large-scale open-pond cultivation. The revolutions in whole-genome-based technologies, coupled with systems biology, metabolic engineering and synthetic biology approaches, would enable the rational design and engineering of algal feedstock and help to fill the gaps between the technical and economical reality and the enormous potential of algal biofuels.
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Lao YM, Xiao L, Luo LX, Jiang JG. Hypoosmotic expression of Dunaliella bardawil ζ-carotene desaturase is attributed to a hypoosmolarity-responsive element different from other key carotenogenic genes. PLANT PHYSIOLOGY 2014; 165:359-72. [PMID: 24632600 PMCID: PMC4012594 DOI: 10.1104/pp.114.235390] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2014] [Accepted: 02/20/2014] [Indexed: 05/08/2023]
Abstract
Some key carotenogenic genes (crts) in Dunaliella bardawil are regulated in response to salt stress partly due to salt-inducible cis-acting elements in their promoters. Thus, we isolated and compared the ζ-carotene desaturase (Dbzds) promoter with other crts promoters including phytoene synthase (Dbpsy), phytoene desaturase (Dbpds), and lycopene β-cyclase1 (DblycB1) to identify salt-inducible element(s) in the Dbzds promoter. In silico analysis of the Dbzds promoter found several potential cis-acting elements, such as abscisic acid response element-like sequence, myelocytomatosis oncogene1 recognition motif, AGC box, anaerobic motif2, and activation sequence factor1 binding site. Remarkably, instead of salt-inducible elements, we found a unique regulatory sequence architecture in the Dbzds promoter: a hypoosmolarity-responsive element (HRE) candidate followed by a potential hypoosmolarity-inducible factor GBF5 binding site. Deletion experiments demonstrated that only HRE, but not the GBF5 binding site, is responsible for hypoosmotic expression of the fusion of Zeocin resistance gene (ble) to the enhanced green fluorescent protein (egfp) chimeric gene under salt stress. Dbzds transcripts were in accordance with those of ble-egfp driven by the wild-type Dbzds promoter. Consequently, Dbzds is hypoosmotically regulated by its promoter, and HRE is responsible for this hypoosmotic response. Finally, the hypoosmolarity mechanism of Dbzds was studied by comparing transcript profiles and regulatory elements of Dbzds with those of Dbpsy, Dbpds, DblycB1, and DblycB2, revealing that different induction characteristics of crts may correlate with regulatory sequence architecture.
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Affiliation(s)
- Yong-Min Lao
- College of Food Science and Engineering, South China University of Technology, Guangzhou 510640, China (Y.-M.L., J.-G.J.); and
- School of Biological Science and Engineering, South China University of Technology, Guangzhou 510006, China (Y.-M.L., L.X., L.-X.L.)
| | - Lan Xiao
- College of Food Science and Engineering, South China University of Technology, Guangzhou 510640, China (Y.-M.L., J.-G.J.); and
- School of Biological Science and Engineering, South China University of Technology, Guangzhou 510006, China (Y.-M.L., L.X., L.-X.L.)
| | - Li-Xin Luo
- College of Food Science and Engineering, South China University of Technology, Guangzhou 510640, China (Y.-M.L., J.-G.J.); and
- School of Biological Science and Engineering, South China University of Technology, Guangzhou 510006, China (Y.-M.L., L.X., L.-X.L.)
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Cui H, Yu X, Wang Y, Cui Y, Li X, Liu Z, Qin S. Evolutionary origins, molecular cloning and expression of carotenoid hydroxylases in eukaryotic photosynthetic algae. BMC Genomics 2013; 14:457. [PMID: 23834441 PMCID: PMC3728230 DOI: 10.1186/1471-2164-14-457] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2013] [Accepted: 06/12/2013] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND Xanthophylls, oxygenated derivatives of carotenes, play critical roles in photosynthetic apparatus of cyanobacteria, algae, and higher plants. Although the xanthophylls biosynthetic pathway of algae is largely unknown, it is of particular interest because they have a very complicated evolutionary history. Carotenoid hydroxylase (CHY) is an important protein that plays essential roles in xanthophylls biosynthesis. With the availability of 18 sequenced algal genomes, we performed a comprehensive comparative analysis of chy genes and explored their distribution, structure, evolution, origins, and expression. RESULTS Overall 60 putative chy genes were identified and classified into two major subfamilies (bch and cyp97) according to their domain structures. Genes in the bch subfamily were found in 10 green algae and 1 red alga, but absent in other algae. In the phylogenetic tree, bch genes of green algae and higher plants share a common ancestor and are of non-cyanobacterial origin, whereas that of red algae is of cyanobacteria. The homologs of cyp97a/c genes were widespread only in green algae, while cyp97b paralogs were seen in most of algae. Phylogenetic analysis on cyp97 genes supported the hypothesis that cyp97b is an ancient gene originated before the formation of extant algal groups. The cyp97a gene is more closely related to cyp97c in evolution than to cyp97b. The two cyp97 genes were isolated from the green alga Haematococcus pluvialis, and transcriptional expression profiles of chy genes were observed under high light stress of different wavelength. CONCLUSIONS Green algae received a β-xanthophylls biosynthetic pathway from host organisms. Although red algae inherited the pathway from cyanobacteria during primary endosymbiosis, it remains unclear in Chromalveolates. The α-xanthophylls biosynthetic pathway is a common feature in green algae and higher plants. The origination of cyp97a/c is most likely due to gene duplication before divergence of green algae and higher plants. Protein domain structures and expression analyses in green alga H. pluvialis indicate that various chy genes are in different manners response to light. The knowledge of evolution of chy genes in photosynthetic eukaryotes provided information of gene cloning and functional investigation of chy genes in algae in the future.
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Affiliation(s)
- Hongli Cui
- Key Laboratory of Coastal Biology and Biological Resources Utilization, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, People's Republic of China
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Skjånes K, Rebours C, Lindblad P. Potential for green microalgae to produce hydrogen, pharmaceuticals and other high value products in a combined process. Crit Rev Biotechnol 2013; 33:172-215. [PMID: 22765907 PMCID: PMC3665214 DOI: 10.3109/07388551.2012.681625] [Citation(s) in RCA: 207] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2011] [Revised: 01/25/2012] [Accepted: 03/29/2012] [Indexed: 12/31/2022]
Abstract
Green microalgae for several decades have been produced for commercial exploitation, with applications ranging from health food for human consumption, aquaculture and animal feed, to coloring agents, cosmetics and others. Several products from green algae which are used today consist of secondary metabolites that can be extracted from the algal biomass. The best known examples are the carotenoids astaxanthin and β-carotene, which are used as coloring agents and for health-promoting purposes. Many species of green algae are able to produce valuable metabolites for different uses; examples are antioxidants, several different carotenoids, polyunsaturated fatty acids, vitamins, anticancer and antiviral drugs. In many cases, these substances are secondary metabolites that are produced when the algae are exposed to stress conditions linked to nutrient deprivation, light intensity, temperature, salinity and pH. In other cases, the metabolites have been detected in algae grown under optimal conditions, and little is known about optimization of the production of each product, or the effects of stress conditions on their production. Some green algae have shown the ability to produce significant amounts of hydrogen gas during sulfur deprivation, a process which is currently studied extensively worldwide. At the moment, the majority of research in this field has focused on the model organism, Chlamydomonas reinhardtii, but other species of green algae also have this ability. Currently there is little information available regarding the possibility for producing hydrogen and other valuable metabolites in the same process. This study aims to explore which stress conditions are known to induce the production of different valuable products in comparison to stress reactions leading to hydrogen production. Wild type species of green microalgae with known ability to produce high amounts of certain valuable metabolites are listed and linked to species with ability to produce hydrogen during general anaerobic conditions, and during sulfur deprivation. Species used today for commercial purposes are also described. This information is analyzed in order to form a basis for selection of wild type species for a future multi-step process, where hydrogen production from solar energy is combined with the production of valuable metabolites and other commercial uses of the algal biomass.
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Affiliation(s)
- Kari Skjånes
- Bioforsk - Norwegian Institute for Agricultural and Environmental Research, Fredrik A. Dahls vei 20, Ås, Norway.
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Wayama M, Ota S, Matsuura H, Nango N, Hirata A, Kawano S. Three-dimensional ultrastructural study of oil and astaxanthin accumulation during encystment in the green alga Haematococcus pluvialis. PLoS One 2013; 8:e53618. [PMID: 23326471 PMCID: PMC3543331 DOI: 10.1371/journal.pone.0053618] [Citation(s) in RCA: 105] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2012] [Accepted: 11/30/2012] [Indexed: 11/30/2022] Open
Abstract
Haematococcus pluvialis is a freshwater species of green algae and is well known for its accumulation of the strong antioxidant astaxanthin, which is used in aquaculture, various pharmaceuticals, and cosmetics. High levels of astaxanthin are present in cysts, which rapidly accumulate when the environmental conditions become unfavorable for normal cell growth. It is not understood, however, how accumulation of high levels of astaxanthin, which is soluble in oil, becomes possible during encystment. Here, we performed ultrastructural 3D reconstruction based on over 350 serial sections per cell to visualize the dynamics of astaxanthin accumulation and subcellular changes during the encystment of H. pluvialis. This study showcases the marked changes in subcellular elements, such as chloroplast degeneration, in the transition from green coccoid cells to red cyst cells during encystment. In green coccoid cells, chloroplasts accounted for 41.7% of the total cell volume, whereas the relative volume of astaxanthin was very low (0.2%). In contrast, oil droplets containing astaxanthin predominated in cyst cells (52.2%), in which the total chloroplast volume was markedly decreased (9.7%). Volumetric observations also demonstrated that the relative volumes of the cell wall, starch grains, pyrenoids, mitochondria, the Golgi apparatus, and the nucleus in a cyst cell are smaller than those in green coccid cells. Our data indicated that chloroplasts are degraded, resulting in a net-like morphology, but do not completely disappear, even at the red cyst stage.
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Affiliation(s)
- Marina Wayama
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, University of Tokyo, Kashiwa, Chiba, Japan
| | - Shuhei Ota
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, University of Tokyo, Kashiwa, Chiba, Japan
- JST-CREST, Kashiwa, Chiba, Japan
| | - Hazuki Matsuura
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, University of Tokyo, Kashiwa, Chiba, Japan
| | | | - Aiko Hirata
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, University of Tokyo, Kashiwa, Chiba, Japan
- Bioimaging Center, Graduate School of Frontier Sciences, University of Tokyo, Kashiwa, Chiba, Japan
| | - Shigeyuki Kawano
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, University of Tokyo, Kashiwa, Chiba, Japan
- JST-CREST, Kashiwa, Chiba, Japan
- * E-mail:
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Liu J, Sun Z, Zhong Y, Huang J, Hu Q, Chen F. Stearoyl-acyl carrier protein desaturase gene from the oleaginous microalga Chlorella zofingiensis: cloning, characterization and transcriptional analysis. PLANTA 2012; 236:1665-76. [PMID: 22855030 DOI: 10.1007/s00425-012-1718-7] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2012] [Accepted: 07/13/2012] [Indexed: 05/03/2023]
Abstract
The green alga Chlorella zofingiensis can accumulate high level of oleic acid (OA, C18:1△(9)) rich oils in response to stress conditions. To understand the regulation of biosynthesis of fatty acid in particular OA at the molecular level, we cloned and characterized the stearoyl acyl carrier protein (ACP) desaturase (SAD) responsible for OA formation through desaturation of stearic acid (C18:0) from C. zofingiensis. Southern blot indicated that the C. zofingiensis genome contained a single copy of SAD, from which the deduced amino acid sequence shared high identity to the corresponding homologs from other microalgae and higher plants. The desaturation activity of SAD was demonstrated in vitro using C18:0-ACP as a substrate. Stress conditions such as high light (HL), nitrogen deficiency (N(-)), or combination of HL and N(-) (HL + N(-)) drastically up-regulated the transcripts of biotin carboxylase (BC, a subunit of ACCase) and SAD, and therefore induced considerably the cellular accumulation of total fatty acids including OA. Glucose (50 mM) gave rise to the similar up-regulation of the two genes and induction of fatty acid accumulation. The accumulation of intracellular reactive oxygen species was found to be associated with the up-regulation of genes. This is the first report of characterization of Chlorella-derived SAD and the results may contribute to understanding of the mechanisms involved in fatty acid/lipid biosynthesis in microalgae.
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Affiliation(s)
- Jin Liu
- Institute for Food and Bioresource Engineering, College of Engineering, Peking University, Beijing, China.
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Cordero BF, Couso I, Leon R, Rodriguez H, Vargas MA. Isolation and characterization of a lycopene ε-cyclase gene of Chlorella (Chromochloris) zofingiensis. Regulation of the carotenogenic pathway by nitrogen and light. Mar Drugs 2012; 10:2069-2088. [PMID: 23118722 PMCID: PMC3475274 DOI: 10.3390/md10092069] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2012] [Revised: 07/24/2012] [Accepted: 09/12/2012] [Indexed: 12/21/2022] Open
Abstract
The isolation and characterization of the lycopene ε-cyclase gene from the green microalga Chlorella (Chromochloris) zofingiensis (Czlcy-e) was performed. This gene is involved in the formation of the carotenoids α-carotene and lutein. Czlcy-e gene encoded a polypeptide of 654 amino acids. A single copy of Czlcy-e was found in C. zofingiensis. Functional analysis by heterologous complementation in Escherichia coli showed the ability of this protein to convert lycopene to δ-carotene. In addition, the regulation of the carotenogenic pathway by light and nitrogen was also studied in C. zofingiensis. High irradiance stress did not increase mRNA levels of neither lycopene β-cyclase gene (lcy-b) nor lycopene ε-cyclase gene (lcy-e) as compared with low irradiance conditions, whereas the transcript levels of psy, pds, chyB and bkt genes were enhanced, nevertheless triggering the synthesis of the secondary carotenoids astaxanthin, canthaxanthin and zeaxanthin and decreasing the levels of the primary carotenoids α-carotene, lutein, violaxanthin and β-carotene. Nitrogen starvation per se enhanced mRNA levels of all genes considered, except lcy-e and pds, but did not trigger the synthesis of astaxanthin, canthaxanthin nor zeaxanthin. The combined effect of both high light and nitrogen starvation stresses enhanced significantly the accumulation of these carotenoids as well as the transcript levels of bkt gene, as compared with the effect of only high irradiance stress.
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Affiliation(s)
- Baldo F. Cordero
- Institute of Plant Biochemistry and Photosynthesis, CIC Cartuja, University of Seville and CSIC, Avda. Americo Vespucio, n° 49, Seville 41092, Spain; (B.F.C.); (I.C.); (M.A.V.)
| | - Inmaculada Couso
- Institute of Plant Biochemistry and Photosynthesis, CIC Cartuja, University of Seville and CSIC, Avda. Americo Vespucio, n° 49, Seville 41092, Spain; (B.F.C.); (I.C.); (M.A.V.)
| | - Rosa Leon
- Department of Chemistry, Experimental Sciences Faculty, University of Huelva, Avda. Fuerzas Armadas s/n, Huelva 27071, Spain;
| | - Herminia Rodriguez
- Institute of Plant Biochemistry and Photosynthesis, CIC Cartuja, University of Seville and CSIC, Avda. Americo Vespucio, n° 49, Seville 41092, Spain; (B.F.C.); (I.C.); (M.A.V.)
| | - Maria Angeles Vargas
- Institute of Plant Biochemistry and Photosynthesis, CIC Cartuja, University of Seville and CSIC, Avda. Americo Vespucio, n° 49, Seville 41092, Spain; (B.F.C.); (I.C.); (M.A.V.)
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Walter MH, Strack D. Carotenoids and their cleavage products: biosynthesis and functions. Nat Prod Rep 2011; 28:663-92. [PMID: 21321752 DOI: 10.1039/c0np00036a] [Citation(s) in RCA: 320] [Impact Index Per Article: 24.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
This review focuses on plant carotenoids, but it also includes progress made on microbial and animal carotenoid metabolism to better understand the functions and the evolution of these structurally diverse compounds with a common backbone. Plants have evolved isogenes for specific key steps of carotenoid biosynthesis with differential expression profiles, whose characteristic features will be compared. Perhaps the most exciting progress has been made in studies of carotenoid cleavage products (apocarotenoids) with an ever-expanding variety of novel functions being discovered. This review therefore covers structural, molecular genetic and functional aspects of carotenoids and apocarotenoids alike. Apocarotenoids are specifically tailored from carotenoids by a family of oxidative cleavage enzymes, but whether there are contributions to their generation from chemical oxidation, photooxidation or other mechanisms is largely unknown. Control of carotenoid homeostasis is discussed in the context of biosynthetic and degradative reactions but also in the context of subcellular environments for deposition and sequestration within and outside of plastids. Other aspects of carotenoid research, including metabolic engineering and synthetic biology approaches, will only be covered briefly.
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Affiliation(s)
- Michael H Walter
- Leibniz-Institut für Pflanzenbiochemie, Abteilung Sekundärstoffwechsel, Weinberg 3, 06120, Halle, Saale, Germany.
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Lemoine Y, Schoefs B. Secondary ketocarotenoid astaxanthin biosynthesis in algae: a multifunctional response to stress. PHOTOSYNTHESIS RESEARCH 2010; 106:155-77. [PMID: 20706789 DOI: 10.1007/s11120-010-9583-3] [Citation(s) in RCA: 183] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2010] [Accepted: 07/05/2010] [Indexed: 05/03/2023]
Abstract
Under stressful environments, many green algae such as Haematococcus pluvialis accumulate secondary ketocarotenoids such as canthaxanthin and astaxanthin. The carotenogenesis, responsible for natural phenomena such as red snows, generally accompanies larger metabolic changes as well as morphological modifications, i.e., the conversion of the green flagellated macrozoids into large red cysts. Astaxanthin accumulation constitutes a convenient way to store energy and carbon, which will be used for further synthesis under less stressful conditions. Besides this, the presence of high amount of astaxanthin enhances the cell resistance to oxidative stress generated by unfavorable environmental conditions including excess light, UV-B irradiation, and nutrition stress and, therefore, confers a higher survival capacity to the cells. This better resistance results from the quenching of oxygen atoms for the synthesis itself as well as from the antioxidant properties of the astaxanthin molecules. Therefore, astaxanthin synthesis corresponds to a multifunctional response to stress. In this contribution, the various biochemical, genetic, and molecular data related to the biosynthesis of ketocarotenoids by Haematococcus pluvialis and other taxa are reviewed and compared. A tentative regulatory model of the biochemical network driving astaxanthin production is proposed.
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Affiliation(s)
- Yves Lemoine
- University Lille Nord de France, UMR 8187 LOG CNRS/University Lille 1, Bât SN2, 59655 Villeneuve d'Ascq Cedex, France
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Liu J, Zhong Y, Sun Z, Huang J, Jiang Y, Sandmann G, Chen F. One amino acid substitution in phytoene desaturase makes Chlorella zofingiensis resistant to norflurazon and enhances the biosynthesis of astaxanthin. PLANTA 2010; 232:61-7. [PMID: 20221629 DOI: 10.1007/s00425-010-1132-y] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2010] [Accepted: 02/10/2010] [Indexed: 05/03/2023]
Abstract
A stable Chlorella zofingiensis mutant (E17) produced by chemical mutagen was characterized with respect to growth, astaxanthin biosynthesis, and phytoene desaturation. The mutant E17 could grow well and produce normal levels of colored carotenoids in the presence of 0.25 microM norflurazon, in which the growth of wild type (WT) cells was greatly limited due to inhibited carotenoid formation. Induced by high-light irradiation or glucose, E17 produced 44 or 36% more astaxanthin than WT when cultured in media without norflurazon. A point mutation (C-T) was revealed to occur in the PDS gene of E17, leading to an amino acid change (L516F) in its coding region. The mutated PDS exhibited 31-fold resistance to norflurazon when compared to WT as determined by an in vitro assay. Surprisingly, the mutated PDS exhibited higher efficiency in converting phytoene to zeta-carotene. No difference in PDS transcripts was found between E17 and WT cells cultured either in normal or induced conditions. In contrast, higher transcript levels of beta-carotene ketolase and hydroxylase were found in the E17 cells. Taken together, we conclude that a point mutation in Chlorella PDS gene makes E17 resistant to norflurazon and synthesize higher amounts of carotenoids including astaxanthin.
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Affiliation(s)
- Jin Liu
- School of Biological Science, The University of Hong Kong, Hong Kong, China
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