1
|
Zhao Y, Han C, Wu Y, Sun Q, Ma M, Xie Z, Sun R, Pei H. Extraction, structural characterization, and antioxidant activity of polysaccharides from three microalgae. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 931:172567. [PMID: 38643871 DOI: 10.1016/j.scitotenv.2024.172567] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2024] [Revised: 04/10/2024] [Accepted: 04/16/2024] [Indexed: 04/23/2024]
Abstract
Microalgal polysaccharides have received much attention due to their potential value in preventing and regulating oxidative damage. This study aims to reveal the mechanisms of regulating oxidative stress and the differences in the yield, structure, and effect of polysaccharides extracted from three microalgae: Golenkinia sp. polysaccharides (GPS), Chlorella sorokiniana polysaccharides (CPS), and Spirulina subsalsa polysaccharides (SPS). Using the same extraction method, GPS, CPS, and SPS were all heteropoly- saccharides composed of small molecular fraction: the monosaccharides mainly comprised galactose (Gal). Among the three, SPS had a higher proportion of small molecular fraction, and a higher proportion of Gal; thus it had the highest yield and antioxidant activity. GPS, CPS, and SPS all showed strong antioxidant activity in vitro, and showed strong ability to regulate oxidative stress, among which SPS was slightly higher. From the analysis of gene expression, the Nrf2-ARE signalling pathway was an important pathway for GPS, CPS, and SPS to regulate cellular oxidative stress. This study provides a theoretical foundation for further research on the utilization of microalgae polysaccharides and product development.
Collapse
Affiliation(s)
- Yang Zhao
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, China
| | - Chun Han
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, China
| | - Yangyingdong Wu
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, China
| | - Qianchen Sun
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, China
| | - Meng Ma
- School of Environmental Science and Engineering, Shandong University, Qingdao 266237, China
| | - Zhen Xie
- School of Environmental Science and Engineering, Shandong University, Qingdao 266237, China
| | - Rong Sun
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, China
| | - Haiyan Pei
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, China; School of Environmental Science and Engineering, Shandong University, Qingdao 266237, China; Shandong Provincial Engineering Center on Environmental Science and Technology, Jinan 250061, China; Institute of Eco-Chongming (IEC), Shanghai 202162, China.
| |
Collapse
|
2
|
De Meester L, Vázquez-Domínguez E, Kassen R, Forest F, Bellon MR, Koskella B, Scherson RA, Colli L, Hendry AP, Crandall KA, Faith DP, Starger CJ, Geeta R, Araki H, Dulloo EM, Souffreau C, Schroer S, Johnson MTJ. A link between evolution and society fostering the UN sustainable development goals. Evol Appl 2024; 17:e13728. [PMID: 38884021 PMCID: PMC11178947 DOI: 10.1111/eva.13728] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Revised: 05/16/2024] [Accepted: 05/17/2024] [Indexed: 06/18/2024] Open
Abstract
Given the multitude of challenges Earth is facing, sustainability science is of key importance to our continued existence. Evolution is the fundamental biological process underlying the origin of all biodiversity. This phylogenetic diversity fosters the resilience of ecosystems to environmental change, and provides numerous resources to society, and options for the future. Genetic diversity within species is also key to the ability of populations to evolve and adapt to environmental change. Yet, the value of evolutionary processes and the consequences of their impairment have not generally been considered in sustainability research. We argue that biological evolution is important for sustainability and that the concepts, theory, data, and methodological approaches used in evolutionary biology can, in crucial ways, contribute to achieving the UN Sustainable Development Goals (SDGs). We discuss how evolutionary principles are relevant to understanding, maintaining, and improving Nature Contributions to People (NCP) and how they contribute to the SDGs. We highlight specific applications of evolution, evolutionary theory, and evolutionary biology's diverse toolbox, grouped into four major routes through which evolution and evolutionary insights can impact sustainability. We argue that information on both within-species evolutionary potential and among-species phylogenetic diversity is necessary to predict population, community, and ecosystem responses to global change and to make informed decisions on sustainable production, health, and well-being. We provide examples of how evolutionary insights and the tools developed by evolutionary biology can not only inspire and enhance progress on the trajectory to sustainability, but also highlight some obstacles that hitherto seem to have impeded an efficient uptake of evolutionary insights in sustainability research and actions to sustain SDGs. We call for enhanced collaboration between sustainability science and evolutionary biology to understand how integrating these disciplines can help achieve the sustainable future envisioned by the UN SDGs.
Collapse
Affiliation(s)
- Luc De Meester
- Leibniz Institute of Freshwater Ecology and Inland Fisheries (IGB) Berlin Germany
- Laboratory of Aquatic Ecology, Evolution and Conservation KU Leuven Leuven Belgium
- Institute of Biology Freie University Berlin Berlin Germany
- Berlin-Brandenburg Institute of Advanced Biodiversity Research (BBIB) Berlin Germany
| | - Ella Vázquez-Domínguez
- Departamento de Ecología de la Biodiversidad, Instituto de Ecología, Universidad Nacional Autónoma de México Ciudad Universitaria Ciudad de México Mexico
- Conservation and Evolutionary Genetics Group Estación Biológica de Doñana (EBD-CSIC) Sevilla Spain
| | - Rees Kassen
- Department of Biology McGill University Montreal Quebec Canada
| | | | - Mauricio R Bellon
- Comisión Nacional Para el Conocimiento y Uso de la Biodiversidad (CONABIO) México City Mexico
- Swette Center for Sustainable Food Systems Arizona State University Tempe Arizona USA
| | - Britt Koskella
- Department of Integrative Biology University of California Berkeley California USA
| | - Rosa A Scherson
- Laboratorio Evolución y Sistemática, Departamento de Silvicultura y Conservación de la Naturaleza Universidad de Chile Santiago Chile
| | - Licia Colli
- Dipartimento di Scienze Animali, Della Nutrizione e Degli Alimenti, BioDNA Centro di Ricerca Sulla Biodiversità e Sul DNA Antico, Facoltà di Scienze Agrarie, Alimentari e Ambientali Università Cattolica del Sacro Cuore Piacenza Italy
| | - Andrew P Hendry
- Redpath Museum & Department of Biology McGill University Montreal Quebec Canada
| | - Keith A Crandall
- Department of Biostatistics and Bioinformatics George Washington University Washington DC USA
- Department of Invertebrate Zoology, US National Museum of Natural History Smithsonian Institution Washington DC USA
| | | | - Craig J Starger
- School of Global Environmental Sustainability Colorado State University Fort Collins Colorado USA
| | - R Geeta
- Department of Botany University of Delhi New Delhi India
| | - Hitoshi Araki
- Research Faculty of Agriculture Hokkaido University Sapporo Japan
| | - Ehsan M Dulloo
- Effective Genetic Resources Conservation and Use Alliance of Bioversity International and CIAT Rome Italy
| | - Caroline Souffreau
- Laboratory of Aquatic Ecology, Evolution and Conservation KU Leuven Leuven Belgium
| | - Sibylle Schroer
- Leibniz Institute of Freshwater Ecology and Inland Fisheries (IGB) Berlin Germany
| | - Marc T J Johnson
- Department of Biology & Centre for Urban Environments University of Toronto Mississauga Mississauga Ontario Canada
| |
Collapse
|
3
|
Ma Y, Sun X, Sun Y, Li H, Li H, Jiao X. Synchronous enhancement of astaxanthin and lipid accumulation in Haematococcus lacustris through co-mutation of ethanol and atmospheric and room temperature plasma: Exploration of characteristics and underlying mechanisms. BIORESOURCE TECHNOLOGY 2024; 394:130305. [PMID: 38199438 DOI: 10.1016/j.biortech.2024.130305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Revised: 01/04/2024] [Accepted: 01/06/2024] [Indexed: 01/12/2024]
Abstract
Haematococcus lacustris is a precious algal species renowned for its ability to simultaneous production of astaxanthin and lipid. However, its slow growth rate necessitates the development of appropriate mutagenesis methodologies to effectively enhance its synchronous production of both astaxanthin and lipid. This study introduced the co-mutation of Atmospheric and Room Temperature Plasma (ARTP) and ethanol. The performance and preliminary mechanisms underlying the combined accumulation of astaxanthin and lipid in H. lacustris under both mutations by ARTP and ethanol were comparatively analyzed. Combined astaxanthin and lipid contents relative to total cell mass in the 110-2 strain reached 54.4%, surpassing that of strain 0-3 and the control by 17.0% and 47.6% respectively. Transcriptome level analysis revealed how both ethanol and ARTP induction promote the expressions of carotenoid and lipid synthesis genes and related enzymatic activities. Upregulation of genes associated with cell activity contributed to lipid and astaxanthin metabolism in multi pathways.
Collapse
Affiliation(s)
- Yihua Ma
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, 13 Yanta Road, Xi'an 710055 China
| | - Xin Sun
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, 13 Yanta Road, Xi'an 710055 China.
| | - Youreng Sun
- Department of Physics, The University of Hong Kong, Pokfulam, Hong Kong, China
| | - Haoyang Li
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, 13 Yanta Road, Xi'an 710055 China
| | - Hongwei Li
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, 13 Yanta Road, Xi'an 710055 China
| | - Xiangfei Jiao
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, 13 Yanta Road, Xi'an 710055 China
| |
Collapse
|
4
|
Chen W, Lin H, Yu W, Huang Y, Lv F, Bai H, Wang S. Organic Semiconducting Polymers for Augmenting Biosynthesis and Bioconversion. JACS AU 2024; 4:3-19. [PMID: 38274265 PMCID: PMC10806880 DOI: 10.1021/jacsau.3c00576] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Revised: 10/31/2023] [Accepted: 11/02/2023] [Indexed: 01/27/2024]
Abstract
Solar-driven biosynthesis and bioconversion are essential for achieving sustainable resources and renewable energy. These processes harness solar energy to produce biomass, chemicals, and fuels. While they offer promising avenues, some challenges and limitations should be investigated and addressed for their improvement and widespread adoption. These include the low utilization of light energy, the inadequate selectivity of products, and the limited utilization of inorganic carbon/nitrogen sources. Organic semiconducting polymers offer a promising solution to these challenges by collaborating with natural microorganisms and developing artificial photosynthetic biohybrid systems. In this Perspective, we highlight the latest advancements in the use of appropriate organic semiconducting polymers to construct artificial photosynthetic biohybrid systems. We focus on how these systems can enhance the natural photosynthetic efficiency of photosynthetic organisms, create artificial photosynthesis capability of nonphotosynthetic organisms, and customize the value-added chemicals of photosynthetic synthesis. By examining the structure-activity relationships and emphasizing the mechanism of electron transfer based on organic semiconducting polymers in artificial photosynthetic biohybrid systems, we aim to shed light on the potential of this novel strategy for artificial photosynthetic biohybrid systems. Notably, these coupling strategies between organic semiconducting polymers and organisms during artificial photosynthetic biohybrid systems will pave the way for a more sustainable future with solar fuels and chemicals.
Collapse
Affiliation(s)
- Weijian Chen
- Beijing National Laboratory
for Molecular Sciences, Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
| | - Hongrui Lin
- Beijing National Laboratory
for Molecular Sciences, Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
| | - Wen Yu
- Beijing National Laboratory
for Molecular Sciences, Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
| | - Yiming Huang
- Beijing National Laboratory
for Molecular Sciences, Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
| | - Fengting Lv
- Beijing National Laboratory
for Molecular Sciences, Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
| | - Haotian Bai
- Beijing National Laboratory
for Molecular Sciences, Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
| | - Shu Wang
- Beijing National Laboratory
for Molecular Sciences, Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
| |
Collapse
|
5
|
Mayali X, Samo TJ, Kimbrel JA, Morris MM, Rolison K, Swink C, Ramon C, Kim YM, Munoz-Munoz N, Nicora C, Purvine S, Lipton M, Stuart RK, Weber PK. Single-cell isotope tracing reveals functional guilds of bacteria associated with the diatom Phaeodactylum tricornutum. Nat Commun 2023; 14:5642. [PMID: 37704622 PMCID: PMC10499878 DOI: 10.1038/s41467-023-41179-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Accepted: 08/24/2023] [Indexed: 09/15/2023] Open
Abstract
Bacterial remineralization of algal organic matter fuels algal growth but is rarely quantified. Consequently, we cannot currently predict whether some bacterial taxa may provide more remineralized nutrients to algae than others. Here, we quantified bacterial incorporation of algal-derived complex dissolved organic carbon and nitrogen and algal incorporation of remineralized carbon and nitrogen in fifteen bacterial co-cultures growing with the diatom Phaeodactylum tricornutum at the single-cell level using isotope tracing and nanoSIMS. We found unexpected strain-to-strain and cell-to-cell variability in net carbon and nitrogen incorporation, including non-ubiquitous complex organic nitrogen utilization and remineralization. We used these data to identify three distinct functional guilds of metabolic interactions, which we termed macromolecule remineralizers, macromolecule users, and small-molecule users, the latter exhibiting efficient growth under low carbon availability. The functional guilds were not linked to phylogeny and could not be elucidated strictly from metabolic capacity as predicted by comparative genomics, highlighting the need for direct activity-based measurements in ecological studies of microbial metabolic interactions.
Collapse
Affiliation(s)
- Xavier Mayali
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA, USA.
| | - Ty J Samo
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA, USA
| | - Jeff A Kimbrel
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA, USA
| | - Megan M Morris
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA, USA
| | - Kristina Rolison
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA, USA
| | - Courtney Swink
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA, USA
| | - Christina Ramon
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA, USA
| | - Young-Mo Kim
- Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA, 99352, USA
| | - Nathalie Munoz-Munoz
- Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA, 99352, USA
| | - Carrie Nicora
- Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA, 99352, USA
| | - Sam Purvine
- Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA, 99352, USA
| | - Mary Lipton
- Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA, 99352, USA
| | - Rhona K Stuart
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA, USA
| | - Peter K Weber
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA, USA
| |
Collapse
|
6
|
Swathik Clarancia P, Naveenarani M, Ashwin Narayan J, Krishna SS, Thirugnanasambandam PP, Valarmathi R, Suresha GS, Gomathi R, Kumar RA, Manickavasagam M, Jegadeesan R, Arun M, Hemaprabha G, Appunu C. Genome-Wide Identification, Characterization and Expression Analysis of Plant Nuclear Factor (NF-Y) Gene Family Transcription Factors in Saccharum spp. Genes (Basel) 2023; 14:1147. [PMID: 37372327 DOI: 10.3390/genes14061147] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2023] [Revised: 05/16/2023] [Accepted: 05/20/2023] [Indexed: 06/29/2023] Open
Abstract
Plant nuclear factor (NF-Y) is a transcriptional activating factor composed of three subfamilies: NF-YA, NF-YB, and NF-YC. These transcriptional factors are reported to function as activators, suppressors, and regulators under different developmental and stress conditions in plants. However, there is a lack of systematic research on the NF-Y gene subfamily in sugarcane. In this study, 51 NF-Y genes (ShNF-Y), composed of 9 NF-YA, 18 NF-YB, and 24 NF-YC genes, were identified in sugarcane (Saccharum spp.). Chromosomal distribution analysis of ShNF-Ys in a Saccharum hybrid located the NF-Y genes on all 10 chromosomes. Multiple sequence alignment (MSA) of ShNF-Y proteins revealed conservation of core functional domains. Sixteen orthologous gene pairs were identified between sugarcane and sorghum. Phylogenetic analysis of NF-Y subunits of sugarcane, sorghum, and Arabidopsis showed that ShNF-YA subunits were equidistant while ShNF-YB and ShNF-YC subunits clustered distinctly, forming closely related and divergent groups. Expression profiling under drought treatment showed that NF-Y gene members were involved in drought tolerance in a Saccharum hybrid and its drought-tolerant wild relative, Erianthus arundinaceus. ShNF-YA5 and ShNF-YB2 genes had significantly higher expression in the root and leaf tissues of both plant species. Similarly, ShNF-YC9 had elevated expression in the leaf and root of E. arundinaceus and in the leaf of a Saccharum hybrid. These results provide valuable genetic resources for further sugarcane crop improvement programs.
Collapse
Affiliation(s)
- Peter Swathik Clarancia
- Division of Crop Improvement, Indian Council of Agricultural Research-Sugarcane Breeding Institute, Coimbatore 641007, India
| | - Murugan Naveenarani
- Division of Crop Improvement, Indian Council of Agricultural Research-Sugarcane Breeding Institute, Coimbatore 641007, India
- Bharathidasan University, Tiruchirappalli 620024, India
| | - Jayanarayanan Ashwin Narayan
- Division of Crop Improvement, Indian Council of Agricultural Research-Sugarcane Breeding Institute, Coimbatore 641007, India
| | - Sakthivel Surya Krishna
- Division of Crop Improvement, Indian Council of Agricultural Research-Sugarcane Breeding Institute, Coimbatore 641007, India
| | | | - Ramanathan Valarmathi
- Division of Crop Improvement, Indian Council of Agricultural Research-Sugarcane Breeding Institute, Coimbatore 641007, India
| | | | - Raju Gomathi
- Division of Crop Improvement, Indian Council of Agricultural Research-Sugarcane Breeding Institute, Coimbatore 641007, India
| | - Raja Arun Kumar
- Division of Crop Improvement, Indian Council of Agricultural Research-Sugarcane Breeding Institute, Coimbatore 641007, India
| | - Markandan Manickavasagam
- Department of Biotechnology, School of Life Sciences, Bharathidasan University, Tiruchirappalli 620024, India
| | - Ramalingam Jegadeesan
- Centre for Plant Molecular Biology and Bioinformatics, Tamil Nadu Agricultural University, Coimbatore 641003, India
| | - Muthukrishnan Arun
- Department of Biotechnology, Bharathiar University, Coimbatore 641046, India
| | - Govindakurup Hemaprabha
- Division of Crop Improvement, Indian Council of Agricultural Research-Sugarcane Breeding Institute, Coimbatore 641007, India
| | - Chinnaswamy Appunu
- Division of Crop Improvement, Indian Council of Agricultural Research-Sugarcane Breeding Institute, Coimbatore 641007, India
| |
Collapse
|
7
|
Schmollinger S, Chen S, Merchant SS. Quantitative elemental imaging in eukaryotic algae. Metallomics 2023; 15:mfad025. [PMID: 37186252 PMCID: PMC10209819 DOI: 10.1093/mtomcs/mfad025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Accepted: 03/03/2023] [Indexed: 05/17/2023]
Abstract
All organisms, fundamentally, are made from the same raw material, namely the elements of the periodic table. Biochemical diversity is achieved by how these elements are utilized, for what purpose, and in which physical location. Determining elemental distributions, especially those of trace elements that facilitate metabolism as cofactors in the active centers of essential enzymes, can determine the state of metabolism, the nutritional status, or the developmental stage of an organism. Photosynthetic eukaryotes, especially algae, are excellent subjects for quantitative analysis of elemental distribution. These microbes utilize unique metabolic pathways that require various trace nutrients at their core to enable their operation. Photosynthetic microbes also have important environmental roles as primary producers in habitats with limited nutrient supplies or toxin contaminations. Accordingly, photosynthetic eukaryotes are of great interest for biotechnological exploitation, carbon sequestration, and bioremediation, with many of the applications involving various trace elements and consequently affecting their quota and intracellular distribution. A number of diverse applications were developed for elemental imaging, allowing subcellular resolution, with X-ray fluorescence microscopy (XFM, XRF) being at the forefront, enabling quantitative descriptions of intact cells in a non-destructive method. This Tutorial Review summarizes the workflow of a quantitative, single-cell elemental distribution analysis of a eukaryotic alga using XFM.
Collapse
Affiliation(s)
- Stefan Schmollinger
- California Institute for Quantitative Biosciences (QB3), University of California, Berkeley, CA 94720, USA
- Departments of Molecular and Cell Biology and Plant and Microbial Biology, University of California, Berkeley, CA 94720, USA
| | - Si Chen
- X-ray Science Division, Argonne National Laboratory, Lemont, IL 60439, USA
| | - Sabeeha S Merchant
- California Institute for Quantitative Biosciences (QB3), University of California, Berkeley, CA 94720, USA
- Departments of Molecular and Cell Biology and Plant and Microbial Biology, University of California, Berkeley, CA 94720, USA
| |
Collapse
|
8
|
Liu H, Bai H, Lam JWY, Kwok RTK, Tang BZ. Recent advances in aggregation-induced emission materials for enhancing solar energy utilization. NANOSCALE HORIZONS 2023; 8:453-459. [PMID: 36799171 DOI: 10.1039/d2nh00506a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Aggregation-induced emission (AIE) materials possessing unique properties in both the solution state and the aggregate state in the aspects of absorption, photoluminescence and heat generation have been well-established for wide applications in the past two decades. In recent years, several emerging applications of AIE materials in solar energy utilization, including luminescent solar concentrators, photosynthesis augmentation and solar steam generation have been reported. This mini-review provides a concise summary of these AIE materials in these aspects.
Collapse
Affiliation(s)
- Haixiang Liu
- HKUST-Shenzhen Research Institute, No. 9 Yuexing 1st RD, South Area, Hi-tech Park, Nanshan, Shenzhen, 518057, China
| | - Haotian Bai
- The Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstruction, Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, 999077, China
| | - Jacky W Y Lam
- HKUST-Shenzhen Research Institute, No. 9 Yuexing 1st RD, South Area, Hi-tech Park, Nanshan, Shenzhen, 518057, China
- The Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstruction, Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, 999077, China
| | - Ryan T K Kwok
- HKUST-Shenzhen Research Institute, No. 9 Yuexing 1st RD, South Area, Hi-tech Park, Nanshan, Shenzhen, 518057, China
- The Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstruction, Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, 999077, China
| | - Ben Zhong Tang
- HKUST-Shenzhen Research Institute, No. 9 Yuexing 1st RD, South Area, Hi-tech Park, Nanshan, Shenzhen, 518057, China
- The Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstruction, Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, 999077, China
- School of Science and Engineering, Shenzhen Institute of Aggregate Science and Technology, The Chinese University of Hong Kong, Shenzhen, Guangdong 518172, China.
| |
Collapse
|
9
|
Huang X, Lin J, Liang J, Kou E, Cai W, Zheng Y, Zhang H, Zhang X, Liu Y, Li W, Lei B. Pyridinic Nitrogen Doped Carbon Dots Supply Electrons to Improve Photosynthesis and Extracellular Electron Transfer of Chlorella pyrenoidosa. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023:e2206222. [PMID: 36907994 DOI: 10.1002/smll.202206222] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Revised: 02/25/2023] [Indexed: 06/18/2023]
Abstract
Optimizing photosynthesis is imperative for providing energy and organics for all life on the earth. Here, carbon dots doped with pyridinic nitrogen (named lev-CDs) are synthesized by the one-pot hydrothermal method, and the structure-function relationship between functional groups on lev-CDs and photosynthesis of Chlorella pyrenoidosa (C. pyrenoidosa) is proposed. Pyridinic nitrogen plays a key role in the positive effect on photosynthesis caused by lev-CDs. In detail, lev-CDs act as electron donors to supply photo-induced electrons to P680+ and QA+ , causing electron transfer from lev-CDs to the photosynthetic electron transport chain in the photosystems. In return, the recombination efficiency of electron-hole pairs on lev-CDs decreases. As a result, the electron transfer rate in the electron transport chain, the activity of photosystem II, and the Calvin cycle are enhanced. Moreover, the electron transfer rate between C. pyrenoidosa and external circumstances enhanced by lev-CDs is about 50%, and electrons exported from C. pyrenoidosa can be used to reduce iron(III). This study is of great significance for engineering nanomaterials to improve photosynthesis.
Collapse
Affiliation(s)
- Xiaoman Huang
- Key Laboratory for Biobased Materials and Energy of Ministry of Education, College of Materials and Energy, South China Agricultural University, Guangzhou, 510642, China
| | - Junjie Lin
- Key Laboratory for Biobased Materials and Energy of Ministry of Education, College of Materials and Energy, South China Agricultural University, Guangzhou, 510642, China
| | - Jiarong Liang
- Key Laboratory for Biobased Materials and Energy of Ministry of Education, College of Materials and Energy, South China Agricultural University, Guangzhou, 510642, China
| | - Erfeng Kou
- Key Laboratory for Biobased Materials and Energy of Ministry of Education, College of Materials and Energy, South China Agricultural University, Guangzhou, 510642, China
| | - Wenxiao Cai
- Key Laboratory for Biobased Materials and Energy of Ministry of Education, College of Materials and Energy, South China Agricultural University, Guangzhou, 510642, China
| | - Yinjian Zheng
- Institute of Urban Agriculture, Chinese Academy of Agricultural Science, Chengdu, 610218, China
| | - Haoran Zhang
- Key Laboratory for Biobased Materials and Energy of Ministry of Education, College of Materials and Energy, South China Agricultural University, Guangzhou, 510642, China
- Maoming Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Maoming, Guangdong, 525100, China
| | - Xuejie Zhang
- Key Laboratory for Biobased Materials and Energy of Ministry of Education, College of Materials and Energy, South China Agricultural University, Guangzhou, 510642, China
| | - Yingliang Liu
- Key Laboratory for Biobased Materials and Energy of Ministry of Education, College of Materials and Energy, South China Agricultural University, Guangzhou, 510642, China
| | - Wei Li
- Key Laboratory for Biobased Materials and Energy of Ministry of Education, College of Materials and Energy, South China Agricultural University, Guangzhou, 510642, China
| | - Bingfu Lei
- Key Laboratory for Biobased Materials and Energy of Ministry of Education, College of Materials and Energy, South China Agricultural University, Guangzhou, 510642, China
- Maoming Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Maoming, Guangdong, 525100, China
| |
Collapse
|
10
|
Hu J, Wang D, Zhang N, Tang K, Bai Y, Tian Y, Li Y, Zhang X. Effects of perfluorooctanoic acid on Microcystis aeruginosa: Stress and self-adaptation mechanisms. JOURNAL OF HAZARDOUS MATERIALS 2023; 445:130396. [PMID: 36436455 DOI: 10.1016/j.jhazmat.2022.130396] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2022] [Revised: 10/29/2022] [Accepted: 11/12/2022] [Indexed: 06/16/2023]
Abstract
The persistent organic pollutant perfluorooctanoic acid (PFOA) is ubiquitous in aquatic environments. However, little is known about its toxicity to microalgae or the mechanisms by which they may self-adapt to it. We found that growth of the bloom-forming cyanobacterium Microcystis aeruginosa was initially inhibited, with inhibition attenuated after 12 d of PFOA exposure. Growth inhibition gradually decreased and stabilized over time. With increasing PFOA concentration, reactive oxygen species levels and superoxide dismutase and photosystem II activity significantly increased, while respiration, NDH-1 activity, and total carbohydrate content significantly decreased. Self-adaptation mechanisms included antioxidant pathways, energy transfer and distribution of photosystems, and repair of the PSI and NDH complexes. The patterns of change in these parameters were consistent with those of the expression levels of genes in their associated metabolic pathways. Our data suggest that PSII overcompensation might be a strategy by which M. aeruginosa contends with oxidative stress induced by PFOA. Multiple downstream photosynthesis-related proteins were upregulated as a function of PFOA exposure time. These findings may help elucidate physiological, genetic stress and self-adaptive responses of microalgae to PFOA exposure.
Collapse
Affiliation(s)
- Jinlu Hu
- School of Life Sciences, Northwestern Polytechnical University, Xi'an, Shaanxi 710072, China.
| | - Dan Wang
- School of Life Sciences, Northwestern Polytechnical University, Xi'an, Shaanxi 710072, China
| | - Ning Zhang
- School of Life Sciences, Northwestern Polytechnical University, Xi'an, Shaanxi 710072, China
| | - Kaixin Tang
- School of Life Sciences, Northwestern Polytechnical University, Xi'an, Shaanxi 710072, China
| | - Yueqiu Bai
- School of Life Sciences, Northwestern Polytechnical University, Xi'an, Shaanxi 710072, China
| | - Yanqiu Tian
- School of Life Sciences, Northwestern Polytechnical University, Xi'an, Shaanxi 710072, China
| | - Yan Li
- Institute of Oil and Gas Technology, PetroChina Changqing Oilfield Company, Xi'an, Shaanxi 710018, China
| | - Xin Zhang
- College of Life Science, South-Central Minzu University, Wuhan, Hubei 430074, China.
| |
Collapse
|
11
|
Cazzaniga S, Perozeni F, Baier T, Ballottari M. Engineering astaxanthin accumulation reduces photoinhibition and increases biomass productivity under high light in Chlamydomonas reinhardtii. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2022; 15:77. [PMID: 35820961 PMCID: PMC9277849 DOI: 10.1186/s13068-022-02173-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Accepted: 06/28/2022] [Indexed: 11/10/2022]
Abstract
Background Astaxanthin is a highly valuable ketocarotenoid with strong antioxidative activity and is natively accumulated upon environmental stress exposure in selected microorganisms. Green microalgae are photosynthetic, unicellular organisms cultivated in artificial systems to produce biomass and industrially relevant bioproducts. While light is required for photosynthesis, fueling carbon fixation processes, application of high irradiance causes photoinhibition and limits biomass productivity. Results Here, we demonstrate that engineered astaxanthin accumulation in the green alga Chlamydomonas reinhardtii conferred high light tolerance, reduced photoinhibition and improved biomass productivity at high irradiances, likely due to strong antioxidant properties of constitutively accumulating astaxanthin. In competitive co-cultivation experiments, astaxanthin-rich Chlamydomonas reinhardtii outcompeted its corresponding parental background strain and even the fast-growing green alga Chlorella vulgaris. Conclusions Metabolic engineering inducing astaxanthin and ketocarotenoids accumulation caused improved high light tolerance and increased biomass productivity in the model species for microalgae Chlamydomonas reinhardtii. Thus, engineering microalgal pigment composition represents a powerful strategy to improve biomass productivities in customized photobioreactors setups. Moreover, engineered astaxanthin accumulation in selected strains could be proposed as a novel strategy to outperform growth of other competing microalgal strains. Supplementary Information The online version contains supplementary material available at 10.1186/s13068-022-02173-3.
Collapse
|
12
|
Tounsi L, Hentati F, Ben Hlima H, Barkallah M, Smaoui S, Fendri I, Michaud P, Abdelkafi S. Microalgae as feedstock for bioactive polysaccharides. Int J Biol Macromol 2022; 221:1238-1250. [PMID: 36067848 DOI: 10.1016/j.ijbiomac.2022.08.206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2022] [Revised: 08/23/2022] [Accepted: 08/31/2022] [Indexed: 11/30/2022]
Abstract
Due to the increase in industrial demand for new biosourced molecules (notably bioactive exopolysaccharides (EPS)), microalgae are gaining popularity because of their nutraceutical potential and benefits health. Such health effects are delivered by specific secondary metabolites, e.g., pigments, exopolysaccharides, polyunsaturated fatty acids, proteins, and glycolipids. These are suitable for the subsequent uses in cosmetic, nutraceutical, pharmaceutical, biofuels, biological waste treatment, animal feed and food fields. In this regard, a special focus has been given in this review to describe the various methods used for extraction and purification of polysaccharides. The second part of the review provides an up-to-date and comprehensive summary of parameters affecting the microalgae growth and insights to maximize the metabolic output by understanding the intricacies of algal development and polysaccharides production. In the ultimate part, the health and nutraceutical claims associated with marine algal bioactive polysaccharides, explaining their noticeable potential for biotechnological applications, are summarized and comprehensively discussed.
Collapse
Affiliation(s)
- Latifa Tounsi
- Laboratoire de Génie Enzymatique et Microbiologie, Équipe de Biotechnologie des Algues, Ecole Nationale d'Ingénieurs de Sfax, Université de Sfax, 3038 Sfax, Tunisia; Université Clermont Auvergne, CNRS, SIGMA Clermont, Institut Pascal, F-63000 Clermont-Ferrand, France
| | - Faiez Hentati
- Université de Lorraine, INRAE, Unité de Recherche Animal et Fonctionnalités des Produits Animaux (UR AFPA), USC 340, Nancy F-54000, France
| | - Hajer Ben Hlima
- Laboratoire de Génie Enzymatique et Microbiologie, Équipe de Biotechnologie des Algues, Ecole Nationale d'Ingénieurs de Sfax, Université de Sfax, 3038 Sfax, Tunisia
| | - Mohamed Barkallah
- Laboratoire de Génie Enzymatique et Microbiologie, Équipe de Biotechnologie des Algues, Ecole Nationale d'Ingénieurs de Sfax, Université de Sfax, 3038 Sfax, Tunisia
| | - Slim Smaoui
- Laboratoire de Microorganismes et de Biomolécules, Centre de Biotechnologie de Sfax, Route Sidi Mansour Km 6 B.P. 117, 3018 Sfax, Tunisia
| | - Imen Fendri
- Laboratoire de Biotechnologie des Plantes Appliquée à l'Amélioration des Cultures, Faculté des Sciences de Sfax, Université de Sfax, 3038 Sfax, Tunisia
| | - Philippe Michaud
- Université Clermont Auvergne, CNRS, SIGMA Clermont, Institut Pascal, F-63000 Clermont-Ferrand, France
| | - Slim Abdelkafi
- Laboratoire de Génie Enzymatique et Microbiologie, Équipe de Biotechnologie des Algues, Ecole Nationale d'Ingénieurs de Sfax, Université de Sfax, 3038 Sfax, Tunisia.
| |
Collapse
|
13
|
Shen L, Yin X. Solar spectral management for natural photosynthesis: from photonics designs to potential applications. NANO CONVERGENCE 2022; 9:36. [PMID: 35930145 PMCID: PMC9356122 DOI: 10.1186/s40580-022-00327-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Accepted: 07/13/2022] [Indexed: 06/15/2023]
Abstract
Photosynthesis is the most important biological process on Earth that converts solar energy to chemical energy (biomass) using sunlight as the sole energy source. The yield of photosynthesis is highly sensitive to the intensity and spectral components of light received by the photosynthetic organisms. Therefore, photon engineering has the potential to increase photosynthesis. Spectral conversion materials have been proposed for solar spectral management and widely investigated for photosynthesis by modifying the quality of light reaching the organisms since the 1990s. Such spectral conversion materials manage the photon spectrum of light by a photoconversion process, and a primary challenge faced by these materials is increasing their efficiencies. This review focuses on emerging spectral conversion materials for augmenting the photosynthesis of plants and microalgae, with a special emphasis on their fundamental design and potential applications in both greenhouse settings and microalgae cultivation systems. Finally, a discussion about the future perspectives in this field is made to overcome the remaining challenges.
Collapse
Affiliation(s)
- Lihua Shen
- Department of Mechanical Engineering, University of Colorado, Boulder, CO, 80309, USA
| | - Xiaobo Yin
- Department of Mechanical Engineering, University of Colorado, Boulder, CO, 80309, USA.
- Materials Science and Engineering Program, University of Colorado, Boulder, CO, 80309, USA.
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong, China.
| |
Collapse
|
14
|
An increase in the membrane lipids recycling by PDAT overexpression stimulates the accumulation of triacylglycerol in Nannochloropsis gaditana. J Biotechnol 2022; 357:28-37. [PMID: 35931238 DOI: 10.1016/j.jbiotec.2022.07.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Revised: 07/18/2022] [Accepted: 07/30/2022] [Indexed: 11/23/2022]
Abstract
Oleaginous microalgae represent potential feedstocks for the sustainable production of lipids thanks to their ability to accumulate triacylglycerols (TAGs). TAG accumulation in several algal species is strongly induced under specific conditions such as nutrient deprivation and high light which, however, also negatively impact growth. Genetic modification of lipogenic pathways can potentially enhance TAG accumulation without negatively affecting growth, avoiding the trade-off between biomass and lipids productivity. In this study, the phospholipid: diacylglycerol acyltransferase (PDAT), an enzyme involved in membrane lipid recycling, was overexpressed in the seawater alga Nannochloropsis gaditana. PDAT overexpression induced increased TAG content in actively growing algae cultures while no effects were observed in conditions naturally stimulating strong lipid accumulation such as high light and nitrogen starvation. The increase of TAG content was confirmed also in a strain cultivated in industrially relevant conditions even though PDAT overexpression, if too strong, the gene overexpression becomes detrimental for growth in the longer term. Results overall suggest that genetic modulation of the PDAT gene represents a promising strategy to increase microalgae lipids content by minimizing negative effects on biomass productivity.
Collapse
|
15
|
Hui C, Schmollinger S, Strenkert D, Holbrook K, Montgomery HR, Chen S, Nelson HM, Weber PK, Merchant SS. Simple steps to enable reproducibility: culture conditions affecting Chlamydomonas growth and elemental composition. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2022; 111:995-1014. [PMID: 35699388 DOI: 10.1111/tpj.15867] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 06/01/2022] [Accepted: 06/03/2022] [Indexed: 05/26/2023]
Abstract
Even subtle modifications in growth conditions elicit acclimation responses affecting the molecular and elemental makeup of organisms, both in the laboratory and in natural habitats. We systematically explored the effect of temperature, pH, nutrient availability, culture density, and access to CO2 and O2 in laboratory-grown algal cultures on growth rate, the ionome, and the ability to accumulate Fe. We found algal cells accumulate Fe in alkaline conditions, even more so when excess Fe is present, coinciding with a reduced growth rate. Using a combination of Fe-specific dyes, X-ray fluorescence microscopy, and NanoSIMS, we show that the alkaline-accumulated Fe was intracellularly sequestered into acidocalcisomes, which are localized towards the periphery of the cells. At high photon flux densities, Zn and Ca specifically over-accumulate, while Zn alone accumulates at low temperatures. The impact of aeration was probed by reducing shaking speeds and changing vessel fill levels; the former increased the Cu quota of cultures, the latter resulted in a reduction in P, Ca, and Mn at low fill levels. Trace element quotas were also affected in the stationary phase, where specifically Fe, Cu, and Zn accumulate. Cu accumulation here depends inversely on the Fe concentration of the medium. Individual laboratory strains accumulate Ca, P, and Cu to different levels. All together, we identified a set of specific changes to growth rate, elemental composition, and the capacity to store Fe in response to subtle differences in culturing conditions of Chlamydomonas, affecting experimental reproducibility. Accordingly, we recommend that these variables be recorded and reported as associated metadata.
Collapse
Affiliation(s)
- Colleen Hui
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA, 90095, USA
- Chemical Sciences Division, Lawrence Livermore National Laboratory, Livermore, CA, 94550, USA
- California Institute for Quantitative Biosciences (QB3), University of California, Berkeley, CA, 94720, USA
| | - Stefan Schmollinger
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA, 90095, USA
- California Institute for Quantitative Biosciences (QB3), University of California, Berkeley, CA, 94720, USA
| | - Daniela Strenkert
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA, 90095, USA
- California Institute for Quantitative Biosciences (QB3), University of California, Berkeley, CA, 94720, USA
| | - Kristen Holbrook
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA, 90095, USA
| | - Hayden R Montgomery
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA, 90095, USA
| | - Si Chen
- Advanced Photon Source, Argonne National Laboratory, Argonne, IL, 60439, USA
| | - Hosea M Nelson
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA, 90095, USA
| | - Peter K Weber
- Lawrence Livermore National Laboratory, Physical and Life Science Directorate, Livermore, CA, 94550, USA
| | - Sabeeha S Merchant
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA, 90095, USA
- California Institute for Quantitative Biosciences (QB3), University of California, Berkeley, CA, 94720, USA
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, 94720, USA
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, 94720, USA
| |
Collapse
|
16
|
Sørensen M, Andersen-Ranberg J, Hankamer B, Møller BL. Circular biomanufacturing through harvesting solar energy and CO 2. TRENDS IN PLANT SCIENCE 2022; 27:655-673. [PMID: 35396170 DOI: 10.1016/j.tplants.2022.03.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 02/16/2022] [Accepted: 03/01/2022] [Indexed: 06/14/2023]
Abstract
Using synthetic biology, it is now time to expand the biosynthetic repertoire of plants and microalgae by utilizing the chloroplast to augment the production of desired high-value compounds and of oil-, carbohydrate-, or protein-enriched biomass based on direct harvesting of solar energy and the consumption of CO2. Multistream product lines based on separate commercialization of the isolated high-value compounds and of the improved bulk products increase the economic potential of the light-driven production system and accelerate commercial scale up. Here we outline the scientific basis for the establishment of such green circular biomanufacturing systems and highlight recent results that make this a realistic option based on cross-disciplinary basic and applied research to advance long-term solutions.
Collapse
Affiliation(s)
- Mette Sørensen
- Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Johan Andersen-Ranberg
- Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Ben Hankamer
- Institute of Molecular Bioscience, The University of Queensland, Brisbane, QLD, Australia
| | - Birger Lindberg Møller
- Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences, University of Copenhagen, Copenhagen, Denmark.
| |
Collapse
|
17
|
Selection-enriched genomic loci (SEGL) reveals genetic loci for environmental adaptation and photosynthetic productivity in Chlamydomonas reinhardtii. ALGAL RES 2022. [DOI: 10.1016/j.algal.2022.102709] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
|
18
|
Shankar U, Lenka SK, Leigh Ackland M, Callahan DL. Review of the structures and functions of algal photoreceptors to optimize bioproduct production with novel bioreactor designs for strain improvement. Biotechnol Bioeng 2022; 119:2031-2045. [PMID: 35441370 DOI: 10.1002/bit.28116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Revised: 04/15/2022] [Accepted: 04/15/2022] [Indexed: 11/11/2022]
Abstract
Microalgae are important renewable feedstock to produce biodiesel and high-value chemicals. Different wavelengths of light influence the growth and metabolic activities of algae. Recent research has identified the light-sensing proteins called photoreceptors that respond to blue or red light. Structural elucidations of algal photoreceptors have gained momentum over recent years. These include channelrhodopsins, PHOT proteins, animal-like cryptochromes, blue-light sensors utilizing flavin-adenine dinucleotide (BLUF) proteins. Pulsing light has also been investigated as a means to optimize energy inputs into bioreactors. This review summarizes the current structural and functional basis of photoreceptor modulation to optimize the growth, production of carotenoids and other high-value metabolites from microalgae. The review also encompasses novel photobioreactor designs that implement different light regimes including light wavelengths and time to optimize algal growth and desired metabolite profiles for high-value products. This article is protected by copyright. All rights reserved.
Collapse
Affiliation(s)
- Uttara Shankar
- TERI-Deakin Nanobiotechnology Centre, The Energy and Resources Institute, Gurugram, Haryana, 122001, India.,Deakin University, Geelong, Australia. School of Life and Environmental Sciences, (Burwood Campus), Centre for Cellular and Molecular biology. 221 Burwood Highway, Burwood, VIC, 3125, Australia
| | - Sangram K Lenka
- TERI-Deakin Nanobiotechnology Centre, The Energy and Resources Institute, Gurugram, Haryana, 122001, India.,Gujarat Biotechnology University, Gandhinagar, Gujarat, 382355, India
| | - M Leigh Ackland
- Deakin University, Geelong, Australia. School of Life and Environmental Sciences, (Burwood Campus), Centre for Cellular and Molecular biology. 221 Burwood Highway, Burwood, VIC, 3125, Australia
| | - Damien L Callahan
- Deakin University, Geelong, Australia. School of Life and Environmental Sciences, (Burwood Campus), Centre for Cellular and Molecular biology. 221 Burwood Highway, Burwood, VIC, 3125, Australia
| |
Collapse
|
19
|
Heterologous Lactate Synthesis in Synechocystis sp. Strain PCC 6803 Causes a Growth Condition-Dependent Carbon Sink Effect. Appl Environ Microbiol 2022; 88:e0006322. [PMID: 35369703 PMCID: PMC9040622 DOI: 10.1128/aem.00063-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Cyanobacteria are considered promising hosts for product synthesis directly from CO2 via photosynthetic carbon assimilation. The introduction of heterologous carbon sinks in terms of product synthesis has been reported to induce the so-called “carbon sink effect,” described as the release of unused photosynthetic capacity by the introduction of additional carbon. This effect is thought to arise from a limitation of carbon metabolism that represents a bottleneck in carbon and electron flow, thus enforcing a downregulation of photosynthetic efficiency. It is not known so far how the cellular source/sink balance under different growth conditions influences the extent of the carbon sink effect and in turn product formation from CO2, constituting a heterologous carbon sink. We compared the Synechocystis sp. strain PCC 6803 wild type (WT) with an engineered lactate-producing strain (SAA023) in defined metabolic states. Unexpectedly, high-light conditions combined with carbon limitation enabled additional carbon assimilation for lactate production without affecting biomass formation. Thus, a strong carbon sink effect only was observed under carbon and thus sink limitation, but not under high-sink conditions. We show that the carbon sink effect was accompanied by an increased rate of alternative electron flow (AEF). Thus, AEF plays a crucial role in the equilibration of source/sink imbalances, presumably via ATP/NADPH balancing. This study emphasizes that the evaluation of the biotechnological potential of cyanobacteria profits from cultivation approaches enabling the establishment of defined metabolic states and respective quantitative analytics. Factors stimulating photosynthesis and carbon fixation are discussed. IMPORTANCE Previous studies reported various and differing effects of the heterologous production of carbon-based molecules on photosynthetic and growth efficiency of cyanobacteria. The typically applied cultivation in batch mode, with continuously changing growth conditions, however, precludes a clear differentiation between the impact of cultivation conditions on cell physiology and effects related to the specific nature of the product and its synthesis pathway. In this study, we employed a continuous cultivation system to maintain defined source/sink conditions and thus metabolic states. This allowed a systematic and quantitative analysis of the effect of NADPH-consuming lactate production on photosynthetic and growth efficiency. This approach enables a realistic evaluation of the biotechnological potential of engineered cyanobacterial strains. For example, the quantum requirement for carbon production was found to constitute an excellent indicator of the source/sink balance and thus a key parameter for photobioprocess optimization. Such knowledge is fundamental for rational and efficient strain and process development.
Collapse
|
20
|
Babich O, Sukhikh S, Larina V, Kalashnikova O, Kashirskikh E, Prosekov A, Noskova S, Ivanova S, Fendri I, Smaoui S, Abdelkafi S, Michaud P, Dolganyuk V. Algae: Study of Edible and Biologically Active Fractions, Their Properties and Applications. PLANTS (BASEL, SWITZERLAND) 2022; 11:plants11060780. [PMID: 35336662 PMCID: PMC8949465 DOI: 10.3390/plants11060780] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Revised: 03/03/2022] [Accepted: 03/10/2022] [Indexed: 06/01/2023]
Abstract
The beneficial properties of algae make them perfect functional ingredients for food products. Algae have a high energy value and are a source of biologically active substances, proteins, fats, carbohydrates, vitamins, and macro- and microelements. They are also rich in polyunsaturated fatty acids, proteins, mycosporine-like amino acids, polysaccharides, polyphenols, carotenoids, sterols, steroids, lectins, halogenated compounds, polyketides, alkaloids, and carrageenans. Different extraction parameters are used depending on the purpose and the substances to be isolated. In this study, the following parameters were used: hydromodule 1:10 and an extraction duration of 1-2 h at the extraction temperature of 25-40 °C. A 30-50% solution of ethanol in water was used as an extractant. Algae extracts can be considered as potential natural sources of biologically active compounds with antimicrobial activity and antiviral properties. The content of crude protein, crude fat, and carbohydrates in U. Prolifera, C. racemosa var. peltata (Chlorophyta), S. oligocystum and S. fusiforme (SF-1) was studied. It was found that C. muelleri (Bacillariophyta), I. galbana (Haptophyta), and T. weissflogii (Bacillariophyta) contain about 1.9 times more omega-3 than omega-6 fatty acids. N. gaditana (Ochrophyta), D. salina (Chlorophyta), P. tricornutum (Bacillaryophyta) and I. galbana (Haptophyta) extracts showed inhibitory activity of varying intensities against E. coli or P. aeruginosa. In addition, algae and algae-derived compounds have been proposed to offer attractive possibilities in the food industry, especially in the meat sector, to evolve functional foods with myriad functionalities. Algae can increase the biological activity of food products, while the further study of the structure of compounds found in algae can broaden their future application possibilities.
Collapse
Affiliation(s)
- Olga Babich
- Institute of Living Systems, Immanuel Kant Baltic Federal University, A. Nevskogo Street 14, 236016 Kaliningrad, Russia; (O.B.); (S.S.); (V.L.); (O.K.); (E.K.); (S.N.); (V.D.)
| | - Stanislav Sukhikh
- Institute of Living Systems, Immanuel Kant Baltic Federal University, A. Nevskogo Street 14, 236016 Kaliningrad, Russia; (O.B.); (S.S.); (V.L.); (O.K.); (E.K.); (S.N.); (V.D.)
| | - Viktoria Larina
- Institute of Living Systems, Immanuel Kant Baltic Federal University, A. Nevskogo Street 14, 236016 Kaliningrad, Russia; (O.B.); (S.S.); (V.L.); (O.K.); (E.K.); (S.N.); (V.D.)
| | - Olga Kalashnikova
- Institute of Living Systems, Immanuel Kant Baltic Federal University, A. Nevskogo Street 14, 236016 Kaliningrad, Russia; (O.B.); (S.S.); (V.L.); (O.K.); (E.K.); (S.N.); (V.D.)
| | - Egor Kashirskikh
- Institute of Living Systems, Immanuel Kant Baltic Federal University, A. Nevskogo Street 14, 236016 Kaliningrad, Russia; (O.B.); (S.S.); (V.L.); (O.K.); (E.K.); (S.N.); (V.D.)
| | - Alexander Prosekov
- Laboratory of Biocatalysis, Kemerovo State University, Krasnaya Street 6, 650043 Kemerovo, Russia;
| | - Svetlana Noskova
- Institute of Living Systems, Immanuel Kant Baltic Federal University, A. Nevskogo Street 14, 236016 Kaliningrad, Russia; (O.B.); (S.S.); (V.L.); (O.K.); (E.K.); (S.N.); (V.D.)
| | - Svetlana Ivanova
- Natural Nutraceutical Biotesting Laboratory, Kemerovo State University, Krasnaya Street 6, 650043 Kemerovo, Russia
- Department of General Mathematics and Informatics, Kemerovo State University, Krasnaya Street 6, 650043 Kemerovo, Russia
| | - Imen Fendri
- Laboratoire de Biotechnologie Végétale Appliquée à l’Amélioration des Cultures, Faculté des Sciences de Sfax, Université de Sfax, Sfax 3038, Tunisia;
| | - Slim Smaoui
- Laboratoire de Microorganismes et de Biomolécules, Centre de Biotechnologie de Sfax, Route Sidi Mansour Km 6 B.P. 117, Sfax 3018, Tunisia;
| | - Slim Abdelkafi
- Laboratoire de Génie Enzymatique et Microbiologie, Equipe de Biotechnologie des Algues, Ecole Nationale d’Ingénieurs de Sfax, Université de Sfax, Sfax 3038, Tunisia;
| | - Philippe Michaud
- Institut Pascal, Université Clermont Auvergne, CNRS, Clermont Auvergne INP, 63000 Clermont-Ferrand, France
| | - Vyacheslav Dolganyuk
- Institute of Living Systems, Immanuel Kant Baltic Federal University, A. Nevskogo Street 14, 236016 Kaliningrad, Russia; (O.B.); (S.S.); (V.L.); (O.K.); (E.K.); (S.N.); (V.D.)
- Department of Bionanotechnology, Kemerovo State University, Krasnaya Street 6, 650043 Kemerovo, Russia
| |
Collapse
|
21
|
Zheng M, Dai J, Ji X, Li D, He Y, Wang M, Huang J, Chen B. An integrated semi-continuous culture to treat original swine wastewater and fix carbon dioxide by an indigenous Chlorella vulgaris MBFJNU-1 in an outdoor photobioreactor. BIORESOURCE TECHNOLOGY 2021; 340:125703. [PMID: 34371337 DOI: 10.1016/j.biortech.2021.125703] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Revised: 07/27/2021] [Accepted: 07/28/2021] [Indexed: 06/13/2023]
Abstract
This work was the first time to evaluate the ability of an isolated Chlorella vulgaris MBFJNU-1 to remove nutrients of original swine wastewater (OSW) and fix carbon dioxide (CO2) under outdoor conditions in a simultaneous manner using column photobioreactors. The results showed that microalga cultivated at 3% CO2 in a batch mode achieved the highest biomass and CO2 fixation rate. Then, a semi-continuous process for OSW treatment and CO2 fixation simultaneously by microalga was established and the renewal rate of this process was deeply investigated. Microalga cultivated at 3% CO2 and 80% renewal rate gave the highest productivities of total biomass, CO2 fixation and the greatest average removal rates of total nitrogen, N-NH4+, total phosphorus and chemical oxygen demand. Taken together, C. vulgaris MBFJNU-1 was the promising microalga under outdoor conditions for swine wastewater treatment and CO2 fixation simultaneously for biofuels and biofertilizer production.
Collapse
Affiliation(s)
- Mingmin Zheng
- College of Life Science, Fujian Normal University, Fuzhou 350117, China; Engineering Research Center of Industrial Microbiology, Ministry of Education, Fujian Normal University, Fuzhou 350117, China
| | - Jingxuan Dai
- College of Life Science, Fujian Normal University, Fuzhou 350117, China
| | - Xiaowei Ji
- College of Life Science, Fujian Normal University, Fuzhou 350117, China
| | - Daogui Li
- College of Life Science, Fujian Normal University, Fuzhou 350117, China
| | - Yongjin He
- College of Life Science, Fujian Normal University, Fuzhou 350117, China; Engineering Research Center of Industrial Microbiology, Ministry of Education, Fujian Normal University, Fuzhou 350117, China.
| | - Mingzi Wang
- College of Life Science, Fujian Normal University, Fuzhou 350117, China; Engineering Research Center of Industrial Microbiology, Ministry of Education, Fujian Normal University, Fuzhou 350117, China
| | - Jian Huang
- College of Life Science, Fujian Normal University, Fuzhou 350117, China; Engineering Research Center of Industrial Microbiology, Ministry of Education, Fujian Normal University, Fuzhou 350117, China
| | - Bilian Chen
- College of Life Science, Fujian Normal University, Fuzhou 350117, China; Engineering Research Center of Industrial Microbiology, Ministry of Education, Fujian Normal University, Fuzhou 350117, China
| |
Collapse
|
22
|
Fattore N, Bellan A, Pedroletti L, Vitulo N, Morosinotto T. Acclimation of photosynthesis and lipids biosynthesis to prolonged nitrogen and phosphorus limitation in Nannochloropsis gaditana. ALGAL RES 2021. [DOI: 10.1016/j.algal.2021.102368] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|
23
|
Ansari FA, Guldhe A, Gupta SK, Rawat I, Bux F. Improving the feasibility of aquaculture feed by using microalgae. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:43234-43257. [PMID: 34173144 DOI: 10.1007/s11356-021-14989-x] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Accepted: 06/15/2021] [Indexed: 06/13/2023]
Abstract
The aquaculture industry is an efficient edible protein producer and grows faster than any other food sector. Therefore, it requires enormous amounts of fish feed. Fish feed directly affects the quality of produced fish, potential health benefits, and cost. Fish meal (FM), fis oil (FO), and plant-based supplements, predominantly used in fish feed, face challenges of low availability, low nutritional value, and high cost. The cost associated with aquaculture feed represents 40-75% of aquaculture production cost and one of the key market drivers for the thriving aquaculture industry. Microalgae are a primary producer in aquatic food chains. Microalgae are expanding continuously in renewable energy, pharmaceutical pigment, wastewater treatment, food, and feed industries. Major components of microalgal biomass are proteins with essential amino acids, lipids with polyunsaturated fatty acids (PUFA), carbohydrates, pigments, and other bioactive compounds. Thus, microalgae can be used as an essential, viable, and alternative feed ingredient in aquaculture feed. In recent times, live algae culture, whole algae, and lipid-extracted algae (LEA) have been tested in fish feed for growth, physiological activity, and nutritional value. The present review discusses the potential application of microalgae in aquaculture feed, its mode of application, nutritional value, and possible replacement of conventional feed ingredients, and disadvantages of plant-based feed. The review also focuses on integrated processes such as algae cultivation in aquaculture wastewater, aquaponics systems, challenges, and future prospects of using microalgae in the aquafeed industry.
Collapse
Affiliation(s)
- Faiz Ahmad Ansari
- Institute for Water and Wastewater Technology, Durban University of Technology, P O Box1334, Durban, 4000, South Africa
| | - Abhishek Guldhe
- Amity Institute of Biotechnology, Amity University, Mumbai, India
| | - Sanjay Kumar Gupta
- Environmental Engineering, Department of Civil Engineering, Indian Institute of Technology, Delhi, India
| | - Ismail Rawat
- Institute for Water and Wastewater Technology, Durban University of Technology, P O Box1334, Durban, 4000, South Africa
| | - Faizal Bux
- Institute for Water and Wastewater Technology, Durban University of Technology, P O Box1334, Durban, 4000, South Africa.
| |
Collapse
|
24
|
Sørensen M, Møller BL. Metabolic Engineering of Photosynthetic Cells – in Collaboration with Nature. Metab Eng 2021. [DOI: 10.1002/9783527823468.ch21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
|
25
|
Guardini Z, Dall’Osto L, Barera S, Jaberi M, Cazzaniga S, Vitulo N, Bassi R. High Carotenoid Mutants of Chlorella vulgaris Show Enhanced Biomass Yield under High Irradiance. PLANTS 2021; 10:plants10050911. [PMID: 34062906 PMCID: PMC8147269 DOI: 10.3390/plants10050911] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Revised: 04/26/2021] [Accepted: 04/27/2021] [Indexed: 12/30/2022]
Abstract
Microalgae represent a carbon-neutral source of bulk biomass, for extraction of high-value compounds and production of renewable fuels. Due to their high metabolic activity and reproduction rates, species of the genus Chlorella are highly productive when cultivated in photobioreactors. However, wild-type strains show biological limitations making algal bioproducts expensive compared to those extracted from other feedstocks. Such constraints include inhomogeneous light distribution due to high optical density of the culture, and photoinhibition of the surface-exposed cells. Thus, the domestication of algal strains for industry makes it increasingly important to select traits aimed at enhancing light-use efficiency while withstanding excess light stress. Carotenoids have a crucial role in protecting against photooxidative damage and, thus, represent a promising target for algal domestication. We applied chemical mutagenesis to Chlorella vulgaris and selected for enhanced tolerance to the carotenoid biosynthesis inhibitor norflurazon. The NFR (norflurazon-resistant) strains showed an increased carotenoid pool size and enhanced tolerance towards photooxidative stress. Growth under excess light revealed an improved carbon assimilation rate of NFR strains with respect to WT. We conclude that domestication of Chlorella vulgaris, by optimizing both carotenoid/chlorophyll ratio and resistance to photooxidative stress, boosted light-to-biomass conversion efficiency under high light conditions typical of photobioreactors. Comparison with strains previously reported for enhanced tolerance to singlet oxygen, reveals that ROS resistance in Chlorella is promoted by at least two independent mechanisms, only one of which is carotenoid-dependent.
Collapse
|
26
|
Biomass and Lipid Productivity by Two Algal Strains of Chlorella sorokiniana Grown in Hydrolysate of Water Hyacinth. ENERGIES 2021. [DOI: 10.3390/en14051411] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Hydrolysate prepared from the chemical hydrolysis of water hyacinth biomass contains a high amount of solubilised carbohydrate and nutrients. This hydrolysate was utilised as a medium for the cultivation of two strains of Chlorella sorokiniana, isolated from a municipal wastewater treatment plant using two different media, i.e., BG-11 and Knop’s medium. Different light intensities, light–dark cycles, and various concentrations of external carbon sources (monosaccharides and inorganic carbon) were used to optimise the microalgal growth. For the accumulation of lipids and carbohydrates, the microalgal strains were transferred to nutrient amended medium (N-amended and P-amended). It was observed that the combined effect of glucose, inorganic carbon, and a 12:12 h light–dark cycle proved to be the optimum parameters for high biomass productivity (~200 mg/L/day). For Chlorella sorokiniana 1 (isolated from BG-11 medium), the maximum carbohydrate content (22%) was found in P-amended medium (N = 0 mg/L, P: 3 mg/L), whereas, high lipid content (17.3%) was recorded in N-amended medium (N = 5 mg/L, P = 0 mg/L). However, for Chlorella sorokiniana 2 (isolated from the Knop’s medium), both lipid (17%) and carbohydrate accumulation (12.3%) were found to be maximum in the N-amended medium. Chlorella sorokiniana 2 showed a high saturated lipid accumulation compared to other strains. Kinetic modelling of the lipid profile revealed that the production rate of fatty acids and their various constituents were species dependent under identical conditions.
Collapse
|
27
|
Incorporating a molecular antenna in diatom microalgae cells enhances photosynthesis. Sci Rep 2021; 11:5209. [PMID: 33664413 PMCID: PMC7933240 DOI: 10.1038/s41598-021-84690-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Accepted: 02/03/2021] [Indexed: 11/22/2022] Open
Abstract
Diatom microalgae have great industrial potential as next-generation sources of biomaterials and biofuels. Effective scale-up of their production can be pursued by enhancing the efficiency of their photosynthetic process in a way that increases the solar-to-biomass conversion yield. A proof-of-concept demonstration is given of the possibility of enhancing the light absorption of algae and of increasing their efficiency in photosynthesis by in vivo incorporation of an organic dye which acts as an antenna and enhances cells’ growth and biomass production without resorting to genetic modification. A molecular dye (Cy5) is incorporated in Thalassiosira weissflogii diatom cells by simply adding it to the culture medium and thus filling the orange gap that limits their absorption of sunlight. Cy5 enhances diatoms’ photosynthetic oxygen production and cell density by 49% and 40%, respectively. Cy5 incorporation also increases by 12% the algal lipid free fatty acid (FFA) production versus the pristine cell culture, thus representing a suitable way to enhance biofuel generation from algal species. Time-resolved spectroscopy reveals Förster Resonance Energy Transfer (FRET) from Cy5 to algal chlorophyll. The present approach lays the basis for non-genetic tailoring of diatoms’ spectral response to light harvesting, opening up new ways for their industrial valorization.
Collapse
|
28
|
Nayar S. Exploring the Role of a Cytokinin-Activating Enzyme LONELY GUY in Unicellular Microalga Chlorella variabilis. FRONTIERS IN PLANT SCIENCE 2021; 11:611871. [PMID: 33613586 PMCID: PMC7891180 DOI: 10.3389/fpls.2020.611871] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Accepted: 12/14/2020] [Indexed: 05/29/2023]
Abstract
LONELY GUY has been previously characterized in flowering plants to be involved in the direct activation of cytokinins. In this study, the function of the only LONELY GUY gene (CvarLOG1) from unicellular green microalga Chlorella variabilis NC64A has been investigated. CvarLOG1 expressed mainly in the lag and log phases of growth and was confirmed to be a cytokinin-activating enzyme. Overexpression of CvarLOG1 in Chlorella led to extended life in culture by almost 10-20 days, creating a "stay-green" phenotype. In the transformed alga, the cell cycle was lengthened due to delayed entry into the G2/M phase contrary to the known role of cytokinins in stimulating G2/M transition possibly due to excessive levels of this hormone. However, due to the sustained growth and delayed senescence, there was an increase in cell number by 11% and in biomass by 46% at the stationary phase, indicating a potential application for the biofuel industry. The total carbohydrate and lipid yield increased by approximately 30 and 20%, respectively. RNA-Seq-based transcriptomic analysis revealed that the genes associated with light and dark reactions of photosynthesis were upregulated, which may be the reason for the increased biomass. These data show that LOG plays an essential role during the cell cycle and in the functioning of the chloroplast and that the pathway leading to direct activation of cytokinins via LOG is functional in algae.
Collapse
|
29
|
Barera S, Dall'Osto L, Bassi R. Effect of lhcsr gene dosage on oxidative stress and light use efficiency by Chlamydomonas reinhardtii cultures. J Biotechnol 2021; 328:12-22. [PMID: 33434600 DOI: 10.1016/j.jbiotec.2020.12.023] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 11/27/2020] [Accepted: 12/31/2020] [Indexed: 10/22/2022]
Abstract
Unicellular green algae, a promising source for renewable biofuels, produce lipid-rich biomass from light and CO2. Productivity in photo-bioreactors is affected by inhomogeneous light distribution from high cell pigment causing heat dissipation of light energy absorbed in excess and shading of the deep layers. Contrasting reports have been published on the relation between photoprotective energy dissipation and productivity. Here, we have re-investigated the relation between energy quenching (qE) activity, photodamage and light use efficiency by comparing WT and two Chlamydomonas reinhardtii strains differing for their complement in LHCSR proteins, which catalyse dissipation of excitation energy in excess (qE). Strains were analysed for ROS production, protein composition, rate of photodamage and productivity assessed under wide light and CO2 conditions. The strain lacking LHCSR1 and knocked down in LHCSR3, thus depleted in qE, produced O2 at significantly higher rate under high light, accompanied by enhanced singlet oxygen release and PSII photodamage. However, biomass productivity of WT was delayed in respect for mutant strains under intermittent light conditions only, implying that PSII activity was not the limiting factor under excess light. Contrary to previous proposals, domestication of Chlamydomonas for carbon assimilation rate in photo-bioreactors by down-regulation of photoprotective energy dissipation was ineffective in increasing algal biomass productivity.
Collapse
Affiliation(s)
- Simone Barera
- Dipartimento di Biotecnologie, Università di Verona, Strada Le Grazie 15, 37134, Verona, Italy.
| | - Luca Dall'Osto
- Dipartimento di Biotecnologie, Università di Verona, Strada Le Grazie 15, 37134, Verona, Italy.
| | - Roberto Bassi
- Dipartimento di Biotecnologie, Università di Verona, Strada Le Grazie 15, 37134, Verona, Italy.
| |
Collapse
|
30
|
Zhou X, Lv F, Huang Y, Liu L, Wang S. Biohybrid Conjugated Polymer Materials for Augmenting Energy Conversion of Bioelectrochemical Systems. Chemistry 2020; 26:15065-15073. [PMID: 32428308 DOI: 10.1002/chem.202002041] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2020] [Indexed: 12/22/2022]
Abstract
Bioelectrochemical systems (BESs) provide favorable opportunities for the sustainable conversion of energy from biological metabolism. Biological photovoltaics (BPVs) and microbial fuel cells (MFCs) respectively realize the conversion of renewable solar energy and bioenergy into electrical energy by utilizing electroactive biological extracellular electron transfer, however, along with this energy conversion progress, relatively poor durability and low output performance are challenges as well as opportunities. Advances in improving bio-electrode interface compatibility will help to solve the problem of insufficient performance and further have a far-reaching impact on the development of bioelectronics. Conjugated polymers (CPs) with specific optical and electrical properties (absorption and emission spectra, energy band structure and electrical conductivity) afforded by π-conjugated backbones are conducive to enhancing the electron generation and output capacity of electroactive organisms. Furthermore, the water solubility, functionality, biocompatibility and mechanical properties optimized through appropriate modification of side chain provide a more adaptive contact interface between biomaterials and electrodes. In this minireview, we summarize the prominent contributions of CPs in the aspect of augmenting the photovoltaic response of BPVs and power supply of MFCs, and specifically discussed the role of CPs with expectation to provide inspirations for the design of bioelectronic devices in the future.
Collapse
Affiliation(s)
- Xin Zhou
- Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China.,University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Fengting Lv
- Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China.,University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Yiming Huang
- Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China.,University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Libing Liu
- Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China.,University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Shu Wang
- Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China.,University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| |
Collapse
|
31
|
de Grahl I, Rout SS, Maple-Grødem J, Reumann S. Development of a constitutive and an auto-inducible high-yield expression system for recombinant protein production in the microalga Nannochloropsis oceanica. Appl Microbiol Biotechnol 2020; 104:8747-8760. [PMID: 32902683 PMCID: PMC7502441 DOI: 10.1007/s00253-020-10789-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 07/10/2020] [Accepted: 07/19/2020] [Indexed: 01/28/2023]
Abstract
Photoautotrophic microalgae offer a great potential as novel hosts for efficient recombinant protein production. Nannochloropsis oceanica produces an extraordinarily high content of polyunsaturated fatty acids, and its robust growth characteristics, published genome sequence and efficient nuclear transformation make N. oceanica a promising candidate for biotechnological applications. To establish a robust and flexible system for recombinant protein production, we cloned six endogenous, potentially constitutive or inducible promoters from N. oceanica strain CCMP1779 and investigated their strength using monomeric Venus as reporter gene. Microscopic pre-screening of individual transformants revealed that the promoters of elongation factor (EF), tubulin (TUB) and nitrate reductase (NR) enabled high reporter gene expression. Comparative quantitative analyses of transformant populations by flow cytometry and qRT-PCR demonstrated the highest Venus expression from the EF promoter and the NR promoter if extended by an N-terminal 14-amino acid leader sequence. The kinetics of reporter gene expression were analysed during photobioreactor cultivation, achieving Venus yields of 0.3% (for EF) and 4.9% (for NR::LS) of total soluble protein. Since inducible expression systems enable the production of toxic proteins, we developed an auto-induction medium for the NR promoter transformants. By switching the N source from ammonium to nitrate in the presence of low ammonium concentrations, the starting point of Venus induction could be fine-tuned and shifted towards exponential growth phase while maintaining high recombinant protein yields. Taken together, we demonstrate that a model recombinant protein can be produced robustly and at very high levels in N. oceanica not only under constitutive but also under auto-inducible cultivation conditions. KEY POINTS: • Nannochloropsis oceanica might serve as host for recombinant protein production. • Comparative promoter strength analyses were conducted for twelve different constructs. • Robust high-yield recombinant protein production was achieved under constitutive conditions. • The nitrate reductase promoter enabled protein production under auto-induction conditions.
Collapse
Affiliation(s)
- Imke de Grahl
- Plant Biochemistry and Infection Biology, Institute of Plant Science and Microbiology, Universität Hamburg, Ohnhorststr. 18, D-22609, Hamburg, Germany
| | - Sweta Suman Rout
- Plant Biochemistry and Infection Biology, Institute of Plant Science and Microbiology, Universität Hamburg, Ohnhorststr. 18, D-22609, Hamburg, Germany
| | - Jodi Maple-Grødem
- The Norwegian Centre for Movement Disorders, Stavanger University Hospital, N-4021, Stavanger, Norway.,Department of Chemistry, Bioscience and Environmental Engineering, University of Stavanger, N-4036, Stavanger, Norway
| | - Sigrun Reumann
- Plant Biochemistry and Infection Biology, Institute of Plant Science and Microbiology, Universität Hamburg, Ohnhorststr. 18, D-22609, Hamburg, Germany.
| |
Collapse
|
32
|
Zhou X, Zeng Y, Tang Y, Huang Y, Lv F, Liu L, Wang S. Artificial regulation of state transition for augmenting plant photosynthesis using synthetic light-harvesting polymer materials. SCIENCE ADVANCES 2020; 6:eabc5237. [PMID: 32923652 PMCID: PMC7449672 DOI: 10.1126/sciadv.abc5237] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Accepted: 07/13/2020] [Indexed: 05/27/2023]
Abstract
Artificial regulation of state transition between photosystem I (PSI) and PSII will be a smart and promising way to improve efficiency of natural photosynthesis. In this work, we found that a synthetic light-harvesting polymer [poly(boron-dipyrromethene-co-fluorene) (PBF)] with green light absorption and far-red emission could improve PSI activity of algae Chlorella pyrenoidosa, followed by further upgrading PSII activity to augment natural photosynthesis. For light-dependent reactions, PBF accelerated photosynthetic electron transfer, and the productions of oxygen, ATP and NADPH were increased by 120, 97, and 76%, respectively. For light-independent reactions, the RuBisCO activity was enhanced by 1.5-fold, while the expression levels of rbcL encoding RuBisCO and prk encoding phosphoribulokinase were up-regulated by 2.6 and 1.5-fold, respectively. Furthermore, PBF could be absorbed by the Arabidopsis thaliana to speed up cell mitosis and enhance photosynthesis. By improving the efficiency of natural photosynthesis, synthetic light-harvesting polymer materials show promising potential applications for biofuel production.
Collapse
Affiliation(s)
- Xin Zhou
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- College of Chemistry, University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Yue Zeng
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- College of Chemistry, University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Yongyan Tang
- Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, P. R. China
| | - Yiming Huang
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- College of Chemistry, University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Fengting Lv
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- College of Chemistry, University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Libing Liu
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- College of Chemistry, University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Shu Wang
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- College of Chemistry, University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| |
Collapse
|
33
|
Okada K, Fujiwara S, Tsuzuki M. Energy conservation in photosynthetic microorganisms. J GEN APPL MICROBIOL 2020; 66:59-65. [PMID: 32336724 DOI: 10.2323/jgam.2020.02.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Photosynthesis is a biological process of energy conversion from solar radiation to useful organic compounds for the photosynthetic organisms themselves. It, thereby, also plays a role of food production for almost all animals on the Earth. The utilization of photosynthesis as an artificial carbon cycle is also attracting a lot of attention regarding its benefits for human life. Hydrogen and biofuels, obtained from photosynthetic microorganisms, such as microalgae and cyanobacteria, will be promising products as energy and material resources. Considering that the efficiency of bioenergy production is insufficient to replace fossil fuels at present, techniques for the industrial utilization of photosynthesis processes need to be developed intensively. Increase in the efficiency of photosynthesis, the yields of target substances, and the growth rates of algae and cyanobacteria must be subjects for efficient industrialization. Here, we overview the whole aspect of the energy production from photosynthesis to biomass production of various photosynthetic microorganisms.
Collapse
Affiliation(s)
- Katsuhiko Okada
- School of Life Sciences, Tokyo University of Pharmacy and Life Sciences
| | - Shoko Fujiwara
- School of Life Sciences, Tokyo University of Pharmacy and Life Sciences
| | - Mikio Tsuzuki
- School of Life Sciences, Tokyo University of Pharmacy and Life Sciences
| |
Collapse
|
34
|
Johansson S, Stephenson P, Edwards R, Yoshida K, Moore C, Terauchi R, Zubkov M, Terry M, Bibby T. Isolation and molecular characterisation of Dunaliella tertiolecta with truncated light-harvesting antenna for enhanced photosynthetic efficiency. ALGAL RES 2020. [DOI: 10.1016/j.algal.2020.101917] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
|
35
|
He J, Chua EL, Qin L. Drought does not induce crassulacean acid metabolism (CAM) but regulates photosynthesis and enhances nutritional quality of Mesembryanthemum crystallinum. PLoS One 2020; 15:e0229897. [PMID: 32142525 PMCID: PMC7059918 DOI: 10.1371/journal.pone.0229897] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Accepted: 02/14/2020] [Indexed: 11/24/2022] Open
Abstract
Physiology and nutritional quality of a facultative CAM plant Mesembryanthemum crystallinum under drought stress alone are poorly understood. To induce drought, M. crystallinum was cultured aeroponically with different nutrient spraying intervals such as 5, 30, 60 and 240 min. The long spraying interval such as 240 min resulted in lower mass of root and shoot, shorter total root length with less tips and smaller surface area, compared to short interval of 5 min. Grown under the longest spraying interval of 240 min, M. crystallinumalso had significantly higher leaf dry matter content but lower leaf succulence. However, CAM acidity was undetectable for any plants. Although M. crystallinum grown under extended spraying intervals had higher photosynthetic pigments, they utilized lesser light energy and did not dissipate heat as effectively as those grown under 5 min. Compare to other shorter spraying intervals, photosynthetic gas exchange rates were significantly reduced under 240 min spraying interval, indicating signs of water deficit stress. Shoot nitrate, total reduced nitrogen, total soluble protein and Rubisco concentrations were similar for all plants. For phytochemicals and dietary minerals, plants grown under 240 min spraying interval had significantly higher values than the other plants. Therefore, drought does not result in the induction of CAM but regulates photosynthetic performance and enhances nutritional quality of M. crystallinum.
Collapse
Affiliation(s)
- Jie He
- National Institute of Education, Nanyang Technological University, Singapore, Singapore
| | - Ee Lyn Chua
- National Institute of Education, Nanyang Technological University, Singapore, Singapore
| | - Lin Qin
- National Institute of Education, Nanyang Technological University, Singapore, Singapore
| |
Collapse
|
36
|
Vecchi V, Barera S, Bassi R, Dall’Osto L. Potential and Challenges of Improving Photosynthesis in Algae. PLANTS 2020; 9:plants9010067. [PMID: 31947868 PMCID: PMC7020468 DOI: 10.3390/plants9010067] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Revised: 12/24/2019] [Accepted: 12/30/2019] [Indexed: 11/16/2022]
Abstract
Sunlight energy largely exceeds the energy required by anthropic activities, and therefore its exploitation represents a major target in the field of renewable energies. The interest in the mass cultivation of green microalgae has grown in the last decades, as algal biomass could be employed to cover a significant portion of global energy demand. Advantages of microalgal vs. plant biomass production include higher light-use efficiency, efficient carbon capture and the valorization of marginal lands and wastewaters. Realization of this potential requires a decrease of the current production costs, which can be obtained by increasing the productivity of the most common industrial strains, by the identification of factors limiting biomass yield, and by removing bottlenecks, namely through domestication strategies aimed to fill the gap between the theoretical and real productivity of algal cultures. In particular, the light-to-biomass conversion efficiency represents one of the major constraints for achieving a significant improvement of algal cell lines. This review outlines the molecular events of photosynthesis, which regulate the conversion of light into biomass, and discusses how these can be targeted to enhance productivity through mutagenesis, strain selection or genetic engineering. This review highlights the most recent results in the manipulation of the fundamental mechanisms of algal photosynthesis, which revealed that a significant yield enhancement is feasible. Moreover, metabolic engineering of microalgae, focused upon the development of renewable fuel biorefineries, has also drawn attention and resulted in efforts for enhancing productivity of oil or isoprenoids.
Collapse
Affiliation(s)
| | | | | | - Luca Dall’Osto
- Correspondence: ; Tel.: +39-045-8027806; Fax: +39-045-8027929
| |
Collapse
|
37
|
Di Caprio F, Altimari P, Pagnanelli F. New strategies enhancing feasibility of microalgal cultivations. ACTA ACUST UNITED AC 2020. [DOI: 10.1016/b978-0-444-64337-7.00016-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
|
38
|
Choi HI, Hwang SW, Sim SJ. Comprehensive approach to improving life-cycle CO 2 reduction efficiency of microalgal biorefineries: A review. BIORESOURCE TECHNOLOGY 2019; 291:121879. [PMID: 31377048 DOI: 10.1016/j.biortech.2019.121879] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Revised: 07/21/2019] [Accepted: 07/22/2019] [Indexed: 06/10/2023]
Abstract
Along with the increase in global awareness of rising CO2 levels, microalgae have attracted considerable interest as a promising CO2 reduction platforms since they exhibit outstanding biomass productivity and are capable of producing numerous valuable products. At this moment, however, two major barriers, relatively low photosynthetic CO2 fixation efficiency and necessity of carbon-intensive microalgal process, obstruct them to be practically utilized. This review suggests effective approaches to improve life-cycle CO2 reduction of microalgal biorefinery. In order to enhance photosynthetic CO2 fixation, strategies to augment carbon content and to increase biomass productivity should be considered. For reducing CO2 emissions associated with the process operations, introduction of efficient process elements, designing of energy-saving process routes, reuse of waste resources and utilization of process integration can be noteworthy options. These comprehensive strategies will provide guidance for microalgal biorefineries to become a practical CO2 reduction technology in near future.
Collapse
Affiliation(s)
- Hong Il Choi
- Department of Chemical and Biological Engineering, Korea University, 145, Anam-ro, Seongbuk-gu, Seoul 02841, South Korea
| | - Sung-Won Hwang
- Department of Chemical and Biological Engineering, Korea University, 145, Anam-ro, Seongbuk-gu, Seoul 02841, South Korea
| | - Sang Jun Sim
- Department of Chemical and Biological Engineering, Korea University, 145, Anam-ro, Seongbuk-gu, Seoul 02841, South Korea.
| |
Collapse
|
39
|
Mock M, Schmid A, Bühler K. Photoautotrophic production of succinate via the oxidative branch of the tricarboxylic acid cycle influences glycogen accumulation in Synechocystis sp. PCC 6803. ALGAL RES 2019. [DOI: 10.1016/j.algal.2019.101645] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
40
|
Khalid M. Nanotechnology and chemical engineering as a tool to bioprocess microalgae for its applications in therapeutics and bioresource management. Crit Rev Biotechnol 2019; 40:46-63. [DOI: 10.1080/07388551.2019.1680599] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Affiliation(s)
- Muneeba Khalid
- Atta ur Rahman School of Applied Biosciences, National University of Sciences and Technology, Islamabad, Pakistan
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, MD, USA
| |
Collapse
|
41
|
|
42
|
Dall’Osto L, Cazzaniga S, Guardini Z, Barera S, Benedetti M, Mannino G, Maffei ME, Bassi R. Combined resistance to oxidative stress and reduced antenna size enhance light-to-biomass conversion efficiency in Chlorella vulgaris cultures. BIOTECHNOLOGY FOR BIOFUELS 2019; 12:221. [PMID: 31534480 PMCID: PMC6745798 DOI: 10.1186/s13068-019-1566-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Accepted: 09/07/2019] [Indexed: 05/20/2023]
Abstract
BACKGROUND Microalgae are efficient producers of lipid-rich biomass, making them a key component in developing a sustainable energy source, and an alternative to fossil fuels. Chlorella species are of special interest because of their fast growth rate in photobioreactors. However, biological constraints still cast a significant gap between the high cost of biofuel and cheap oil, thus hampering perspective of producing CO2-neutral biofuels. A key issue is the inefficient use of light caused by its uneven distribution in the culture that generates photoinhibition of the surface-exposed cells and darkening of the inner layers. Efficient biofuel production, thus, requires domestication, including traits which reduce optical density of cultures and enhance photoprotection. RESULTS We applied two steps of mutagenesis and phenotypic selection to the microalga Chlorella vulgaris. First, a pale-green mutant (PG-14) was selected, with a 50% reduction of both chlorophyll content per cell and LHCII complement per PSII, with respect to WT. PG-14 showed a 30% increased photon conversion into biomass efficiency vs. WT. A second step of mutagenesis of PG-14, followed by selection for higher tolerance to Rose Bengal, led to the isolation of pale-green genotypes, exhibiting higher resistance to singlet oxygen (strains SOR). Growth in photobioreactors under high light conditions showed an enhanced biomass production of SOR strains with respect to PG-14. When compared to WT strain, biomass yield of the pale green + sor genotype was enhanced by 68%. CONCLUSIONS Domestication of microalgae like Chlorella vulgaris, by optimizing both light distribution and ROS resistance, yielded an enhanced carbon assimilation rate in photobioreactor.
Collapse
Affiliation(s)
- Luca Dall’Osto
- Dipartimento di Biotecnologie, Università di Verona, Strada Le Grazie 15, 37134 Verona, Italy
| | - Stefano Cazzaniga
- Dipartimento di Biotecnologie, Università di Verona, Strada Le Grazie 15, 37134 Verona, Italy
| | - Zeno Guardini
- Dipartimento di Biotecnologie, Università di Verona, Strada Le Grazie 15, 37134 Verona, Italy
| | - Simone Barera
- Dipartimento di Biotecnologie, Università di Verona, Strada Le Grazie 15, 37134 Verona, Italy
| | - Manuel Benedetti
- Dipartimento di Biotecnologie, Università di Verona, Strada Le Grazie 15, 37134 Verona, Italy
| | - Giuseppe Mannino
- Dipartimento di Scienze della Vita e Biologia dei Sistemi, Unità di Fisiologia Vegetale, Università di Torino, Via Quarello 15/a, 10135 Turin, Italy
| | - Massimo E. Maffei
- Dipartimento di Scienze della Vita e Biologia dei Sistemi, Unità di Fisiologia Vegetale, Università di Torino, Via Quarello 15/a, 10135 Turin, Italy
| | - Roberto Bassi
- Dipartimento di Biotecnologie, Università di Verona, Strada Le Grazie 15, 37134 Verona, Italy
| |
Collapse
|
43
|
Grund M, Jakob T, Wilhelm C, Bühler B, Schmid A. Electron balancing under different sink conditions reveals positive effects on photon efficiency and metabolic activity of Synechocystis sp. PCC 6803. BIOTECHNOLOGY FOR BIOFUELS 2019; 12:43. [PMID: 30858880 PMCID: PMC6391784 DOI: 10.1186/s13068-019-1378-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Accepted: 02/14/2019] [Indexed: 05/19/2023]
Abstract
BACKGROUND Cyanobacteria are ideal model organisms to exploit photosynthetically derived electrons or fixed carbon for the biotechnological synthesis of high value compounds and energy carriers. Much effort is spent on the rational design of heterologous pathways to produce value-added chemicals. Much less focus is drawn on the basic physiological responses and potentials of phototrophs to deal with natural or artificial electron and carbon sinks. However, an understanding of how electron sinks influence or regulate cellular physiology is essential for the efficient application of phototrophic organisms in an industrial setting, i.e., to achieve high productivities and product yields. RESULTS The physiological responses of the cyanobacterium Synechocystis sp. PCC 6803 to electron sink variation were investigated in a systematic and quantitative manner. A variation in electron demand was achieved by providing two N sources with different degrees of reduction. By additionally varying light and CO2 availabilities, steady state conditions with strongly differing source-sink ratios were established. Balancing absorbed photons and electrons used for different metabolic processes revealed physiological responses to sink/source ratio variation. Surprisingly, an additional electron sink under light and thus energy limitation was found not to hamper growth, but was compensated by improved photosynthetic efficiency and activity. In the absence of carbon and light limitation, an increase in electron demand even stimulated carbon assimilation and growth. CONCLUSION The metabolism of Synechocystis sp. PCC 6803 is highly flexible regarding the compensation of additional electron demands. Under light limitation, photosynthesis obviously does not necessarily run at its maximal capacity, possibly for the sake of robustness. Increased electron demands can even boost photosynthetic activity and growth.
Collapse
Affiliation(s)
- Marcel Grund
- Department of Solar Materials, Helmholtz Center for Environmental Research GmbH–UFZ, Permoserstraße 15, 04318 Leipzig, Germany
| | - Torsten Jakob
- Plant Physiology Group, Institute for Biology, University of Leipzig, Johannisallee 21-23, 04103 Leipzig, Germany
| | - Christian Wilhelm
- Plant Physiology Group, Institute for Biology, University of Leipzig, Johannisallee 21-23, 04103 Leipzig, Germany
| | - Bruno Bühler
- Department of Solar Materials, Helmholtz Center for Environmental Research GmbH–UFZ, Permoserstraße 15, 04318 Leipzig, Germany
| | - Andreas Schmid
- Department of Solar Materials, Helmholtz Center for Environmental Research GmbH–UFZ, Permoserstraße 15, 04318 Leipzig, Germany
| |
Collapse
|
44
|
Benedetti M, Vecchi V, Barera S, Dall’Osto L. Biomass from microalgae: the potential of domestication towards sustainable biofactories. Microb Cell Fact 2018; 17:173. [PMID: 30414618 PMCID: PMC6230293 DOI: 10.1186/s12934-018-1019-3] [Citation(s) in RCA: 98] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2018] [Accepted: 10/31/2018] [Indexed: 12/22/2022] Open
Abstract
Interest in bulk biomass from microalgae, for the extraction of high-value nutraceuticals, bio-products, animal feed and as a source of renewable fuels, is high. Advantages of microalgal vs. plant biomass production include higher yield, use of non-arable land, recovery of nutrients from wastewater, efficient carbon capture and faster development of new domesticated strains. Moreover, adaptation to a wide range of environmental conditions evolved a great genetic diversity within this polyphyletic group, making microalgae a rich source of interesting and useful metabolites. Microalgae have the potential to satisfy many global demands; however, realization of this potential requires a decrease of the current production costs. Average productivity of the most common industrial strains is far lower than maximal theoretical estimations, suggesting that identification of factors limiting biomass yield and removing bottlenecks are pivotal in domestication strategies aimed to make algal-derived bio-products profitable on the industrial scale. In particular, the light-to-biomass conversion efficiency represents a major constraint to finally fill the gap between theoretical and industrial productivity. In this respect, recent results suggest that significant yield enhancement is feasible. Full realization of this potential requires further advances in cultivation techniques, together with genetic manipulation of both algal physiology and metabolic networks, to maximize the efficiency with which solar energy is converted into biomass and bio-products. In this review, we draft the molecular events of photosynthesis which regulate the conversion of light into biomass, and discuss how these can be targeted to enhance productivity through mutagenesis, strain selection or genetic engineering. We outline major successes reached, and promising strategies to achieving significant contributions to future microalgae-based biotechnology.
Collapse
Affiliation(s)
- Manuel Benedetti
- Dipartimento di Biotecnologie, Università di Verona, Strada Le Grazie 15, 37134 Verona, Italy
| | - Valeria Vecchi
- Dipartimento di Biotecnologie, Università di Verona, Strada Le Grazie 15, 37134 Verona, Italy
| | - Simone Barera
- Dipartimento di Biotecnologie, Università di Verona, Strada Le Grazie 15, 37134 Verona, Italy
| | - Luca Dall’Osto
- Dipartimento di Biotecnologie, Università di Verona, Strada Le Grazie 15, 37134 Verona, Italy
| |
Collapse
|
45
|
Spontaneous mutation rate as a source of diversity for improving desirable traits in cultured microalgae. ALGAL RES 2018. [DOI: 10.1016/j.algal.2018.08.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
|
46
|
Berepiki A, Gittins JR, Moore CM, Bibby TS. Rational engineering of photosynthetic electron flux enhances light-powered cytochrome P450 activity. Synth Biol (Oxf) 2018; 3:ysy009. [PMID: 32995517 PMCID: PMC7445785 DOI: 10.1093/synbio/ysy009] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Revised: 05/04/2018] [Accepted: 05/25/2018] [Indexed: 11/21/2022] Open
Abstract
In this study, we exploited a modified photosynthetic electron transfer chain (PET) in the model cyanobacterium Synechococcus PCC 7002, where electrons derived from water-splitting are used to power reactions catalyzed by a heterologous cytochrome P450 (CYP1A1). A simple in vivo fluorescent assay for CYP1A1 activity was employed to determine the impact of rationally engineering of photosynthetic electron flow. This showed that knocking out a subunit of the type I NADH dehydrogenase complex (NDH-1), suggested to be involved in cyclic photosynthetic electron flow (ΔndhD2), can double the activity of CYP1A1, with a concomitant increase in the flux of electrons from photosynthesis. This also resulted in an increase in cellular adenosine triphosphate (ATP) and the ATP/nicotinamide adenine dinucleotide phosphate (NADPH) ratio, suggesting that expression of a heterologous electron sink in photosynthetic organisms can be used to modify the bioenergetic landscape of the cell. We therefore demonstrate that CYP1A1 is limited by electron supply and that photosynthesis can be re-engineered to increase heterologous P450 activity for the production of high-value bioproducts. The increase in cellular ATP achieved could be harnessed to support metabolically demanding heterologous processes. Furthermore, this experimental system could provide valuable insights into the mechanisms of photosynthesis.
Collapse
Affiliation(s)
- Adokiye Berepiki
- Ocean and Earth Science, University of Southampton, Waterfront Campus, National Oceanography Centre, Southampton SO14 3ZH, UK.,Manchester Institute of Biotechnology, University of Manchester, Princess St, Manchester M1 7DN, UK
| | - John R Gittins
- Ocean and Earth Science, University of Southampton, Waterfront Campus, National Oceanography Centre, Southampton SO14 3ZH, UK
| | - C Mark Moore
- Ocean and Earth Science, University of Southampton, Waterfront Campus, National Oceanography Centre, Southampton SO14 3ZH, UK
| | - Thomas S Bibby
- Ocean and Earth Science, University of Southampton, Waterfront Campus, National Oceanography Centre, Southampton SO14 3ZH, UK
| |
Collapse
|
47
|
Song HG, Byeon SY, Chung GY, Jung SM, Choi JI, Shin HS. A systematic correlation analysis of carotenoids, chlorophyll, non-pigmented cell mass, and cell number for the blueprint of Dunaliella salina culture in a photobioreactor. Bioprocess Biosyst Eng 2018; 41:1295-1303. [PMID: 29808420 DOI: 10.1007/s00449-018-1957-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Accepted: 05/23/2018] [Indexed: 11/24/2022]
Abstract
Microalgal carotenoids are attractive health ingredients, but their production should be optimized to improve cost-effectiveness. Understanding cellular physiology centered on carotenoid synthesis is the prerequisite for this work. Therefore, systematic correlation analyses were conducted among chlorophyll, carotenoids, non-pigmented cell mass, and cell number of Dunaliella salina in a specified condition over a relatively long culture time. First, an integrated correlation was performed: a temporal profile of the carotenoids was correlated with those of other factors, including chlorophyll, non-pigmented cell mass, and cell number. Pearson and Spearman correlation analyses were performed to identify linearity and monotonicity of the correlation, respectively, and then cross-correlation was executed to determine if the correlation had a time lag. Second, to understand the cellular potential of metabolism, the procedure was repeated to provide a data set composed of the specific synthesis rates of the factors or growth rate, which additionally provided kinetic correlations among the constituting components of the cell, excluding the effect of cell number. This systematic approach could generate a blueprint model that is composed of only what it needs, which could make it possible to efficiently control and optimize the process.
Collapse
Affiliation(s)
- Hyeon Gi Song
- Department of Biological Engineering, Inha University, Incheon, South Korea
| | - Seon Yeong Byeon
- Department of Biological Engineering, Inha University, Incheon, South Korea
| | - Goo Yong Chung
- Department of Biological Engineering, Inha University, Incheon, South Korea
| | - Sang-Myung Jung
- Department of Biological Engineering, Inha University, Incheon, South Korea
| | - Jung Il Choi
- Department of Biological Engineering, Inha University, Incheon, South Korea
| | - Hwa Sung Shin
- Department of Biological Engineering, Inha University, Incheon, South Korea.
| |
Collapse
|
48
|
Dann M, Leister D. Enhancing (crop) plant photosynthesis by introducing novel genetic diversity. Philos Trans R Soc Lond B Biol Sci 2018; 372:rstb.2016.0380. [PMID: 28808099 DOI: 10.1098/rstb.2016.0380] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/04/2017] [Indexed: 12/22/2022] Open
Abstract
Although some elements of the photosynthetic light reactions might appear to be ideal, the overall efficiency of light conversion to biomass has not been optimized during evolution. Because crop plants are depleted of genetic diversity for photosynthesis, efforts to enhance its efficiency with respect to light conversion to yield must generate new variation. In principle, three sources of natural variation are available: (i) rare diversity within extant higher plant species, (ii) photosynthetic variants from algae, and (iii) reconstruction of no longer extant types of plant photosynthesis. Here, we argue for a novel approach that outsources crop photosynthesis to a cyanobacterium that is amenable to adaptive evolution. This system offers numerous advantages, including a short generation time, virtually unlimited population sizes and high mutation rates, together with a versatile toolbox for genetic manipulation. On such a synthetic bacterial platform, 10 000 years of (crop) plant evolution can be recapitulated within weeks. Limitations of this system arise from its unicellular nature, which cannot reproduce all aspects of crop photosynthesis. But successful establishment of such a bacterial host for crop photosynthesis promises not only to enhance the performance of eukaryotic photosynthesis but will also reveal novel facets of the molecular basis of photosynthetic flexibility.This article is part of the themed issue 'Enhancing photosynthesis in crop plants: targets for improvement'.
Collapse
Affiliation(s)
- Marcel Dann
- Plant Molecular Biology, Faculty of Biology, Ludwig-Maximilians University of Munich, Großhaderner Str. 2, 82152 Planegg-Martinsried, Germany
| | - Dario Leister
- Plant Molecular Biology, Faculty of Biology, Ludwig-Maximilians University of Munich, Großhaderner Str. 2, 82152 Planegg-Martinsried, Germany
| |
Collapse
|
49
|
Corcoran AA, Saunders MA, Hanley AP, Lee PA, Lopez S, Ryan R, Yohn CB. Iterative screening of an evolutionary engineered Desmodesmus generates robust field strains with pesticide tolerance. ALGAL RES 2018. [DOI: 10.1016/j.algal.2018.02.026] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
|
50
|
Li Y, Xu Y, Zheng T, Wang H. Amino acids in cell wall of Gram-positive bacterium Micrococcus sp. hsn08 with flocculation activity on Chlorella vulgaris biomass. BIORESOURCE TECHNOLOGY 2018; 249:417-424. [PMID: 29065323 DOI: 10.1016/j.biortech.2017.10.056] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Revised: 10/09/2017] [Accepted: 10/13/2017] [Indexed: 06/07/2023]
Abstract
The aim of this work was to investigate the flocculation mechanism by Gram-positive bacterium, Micrococcus sp. hsn08 as a means for harvesting Chlorella vulgaris biomass. Bacterial cells of Micrococcus sp. hsn08 were added into algal culture to harvest algal cells through direct contacting with algae to form flocs. Viability dependence test confirmed that flocculation activity does not depend on live bacteria, but on part of the peptidoglycan. The further investigation has determined that amino acids in cell wall play an important role to flocculate algal cells. Positively charged calcium can combine bacterial and algal cells together, and form a bridge between them, thereby forming the flocs, suggesting that ions bridging is the main flocculation mechanism. These results suggest that bacterial cells of Micrococcus sp. hsn08 can be applied to harvest microalgae biomass with the help of amino acids in cell wall.
Collapse
Affiliation(s)
- Yi Li
- College of Life Sciences, Henan Normal University, Xinxiang 453007, China
| | - Yanting Xu
- College of Life Sciences, Henan Normal University, Xinxiang 453007, China
| | - Tianling Zheng
- State Key Laboratory of Marine Environmental Science, School of Life Sciences, Xiamen University, Xiamen 361005, China
| | - Hailei Wang
- College of Life Sciences, Henan Normal University, Xinxiang 453007, China.
| |
Collapse
|