1
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Ou Y, Qin Y, Feng S, Yang H. Dual stress factors adaptive evolution for high EPA production in Schizochytrium sp. and metabolomics mechanism analysis. Bioprocess Biosyst Eng 2024; 47:863-875. [PMID: 38687387 DOI: 10.1007/s00449-024-03013-4] [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: 01/27/2024] [Accepted: 04/02/2024] [Indexed: 05/02/2024]
Abstract
Eicosapentaenoic acid (EPA) is a vital ɷ-3 polyunsaturated fatty acid (PUFA) for human body with various physiological functions. In this study, we proposed an adaptive evolutionary strategy based on high-temperature and high-oxygen two-factor stress to increase the EPA production capacity of Schizochytrium. High-temperature stress was used to increase EPA yield, and high oxygen was implemented to continuously stimulate cell growth and lipid accumulation. The biomass and EPA production of ALE-D50 reached 35.33 g/L and 1.54 g/L, which were 43.85% and 71.11% higher than that of the original strain, respectively. Lower in vivo reactive oxygen species levels indicated that the evolved strain possessed stronger antioxidant activity. Liquid chromatography-mass spectrometry metabolomics showed that enhanced glucose consumption and glycolysis metabolism, as well as a weakened tricarboxylic acid cycle and reduced amino acid metabolic tributaries in the evolved strain, might be associated with increased growth and EPA synthesis. Finally, the lipid production and EPA production in a fed-batch fermentation were further increased to 48.93 g/L and 3.55 g/L, improving by 54.30% and 90.86%, respectively. This study provides a novel pathway for promoting EPA biosynthesis in Schizochytrium.
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Affiliation(s)
- Ying Ou
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, WuXi, 214122, People's Republic of China
| | - Yu Qin
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, WuXi, 214122, People's Republic of China
| | - Shoushuai Feng
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, WuXi, 214122, People's Republic of China
| | - Hailin Yang
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, WuXi, 214122, People's Republic of China.
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2
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Webster LJ, Villa-Gomez D, Brown R, Clarke W, Schenk PM. A synthetic biology approach for the treatment of pollutants with microalgae. Front Bioeng Biotechnol 2024; 12:1379301. [PMID: 38646010 PMCID: PMC11032018 DOI: 10.3389/fbioe.2024.1379301] [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: 01/30/2024] [Accepted: 03/11/2024] [Indexed: 04/23/2024] Open
Abstract
The increase in global population and industrial development has led to a significant release of organic and inorganic pollutants into water streams, threatening human health and ecosystems. Microalgae, encompassing eukaryotic protists and prokaryotic cyanobacteria, have emerged as a sustainable and cost-effective solution for removing these pollutants and mitigating carbon emissions. Various microalgae species, such as C. vulgaris, P. tricornutum, N. oceanica, A. platensis, and C. reinhardtii, have demonstrated their ability to eliminate heavy metals, salinity, plastics, and pesticides. Synthetic biology holds the potential to enhance microalgae-based technologies by broadening the scope of treatment targets and improving pollutant removal rates. This review provides an overview of the recent advances in the synthetic biology of microalgae, focusing on genetic engineering tools to facilitate the removal of inorganic (heavy metals and salinity) and organic (pesticides and plastics) compounds. The development of these tools is crucial for enhancing pollutant removal mechanisms through gene expression manipulation, DNA introduction into cells, and the generation of mutants with altered phenotypes. Additionally, the review discusses the principles of synthetic biology tools, emphasizing the significance of genetic engineering in targeting specific metabolic pathways and creating phenotypic changes. It also explores the use of precise engineering tools, such as CRISPR/Cas9 and TALENs, to adapt genetic engineering to various microalgae species. The review concludes that there is much potential for synthetic biology based approaches for pollutant removal using microalgae, but there is a need for expansion of the tools involved, including the development of universal cloning toolkits for the efficient and rapid assembly of mutants and transgenic expression strains, and the need for adaptation of genetic engineering tools to a wider range of microalgae species.
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Affiliation(s)
- Luke J. Webster
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane, QLD, Australia
| | - Denys Villa-Gomez
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane, QLD, Australia
- School of Civil Engineering, The University of Queensland, Brisbane, QLD, Australia
| | - Reuben Brown
- Algae Biotechnology Laboratory, School of Agriculture and Food Sustainability, The University of Queensland, Brisbane, QLD, Australia
| | - William Clarke
- School of Civil Engineering, The University of Queensland, Brisbane, QLD, Australia
| | - Peer M. Schenk
- Algae Biotechnology Laboratory, School of Agriculture and Food Sustainability, The University of Queensland, Brisbane, QLD, Australia
- Algae Biotechnology, Sustainable Solutions Hub, Global Sustainable Solutions Pty Ltd, Brisbane, QLD, Australia
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3
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Pontén O, Xiao L, Kutter J, Cui Y, Wählby C, Behrendt L. PACMan: A software package for automated single-cell chlorophyll fluorometry. Cytometry A 2024; 105:203-213. [PMID: 37864330 DOI: 10.1002/cyto.a.24808] [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: 04/01/2023] [Revised: 10/03/2023] [Accepted: 10/07/2023] [Indexed: 10/22/2023]
Abstract
Microalgae, small photosynthetic unicells, are of great interest to ecology, ecotoxicology and biotechnology and there is a growing need to investigate the ability of cells to photosynthesize under variable conditions. Current strategies involve hand-operated pulse-amplitude-modulated (PAM) chlorophyll fluorimeters, which can provide detailed insights into the photophysiology of entire populations- or individual cells of microalgae but are typically limited in their throughput. To increase the throughput of a commercially available MICROSCOPY-PAM system, we present the PAM Automation Control Manager ('PACMan'), an open-source Python software package that automates image acquisition, microscopy stage control and the triggering of external hardware components. PACMan comes with a user-friendly graphical user interface and is released together with a stand-alone tool (PAMalysis) for the automated calculation of per-cell maximum quantum efficiencies (= Fv /Fm ). Using these two software packages, we successfully tracked the photophysiology of >1000 individual cells of green algae (Chlamydomonas reinhardtii) and dinoflagellates (genus Symbiodiniaceae) within custom-made microfluidic devices. Compared to the manual operation of MICROSCOPY-PAM systems, this represents a 10-fold increase in throughput. During experiments, PACMan coordinated the movement of the microscope stage and triggered the MICROSCOPY-PAM system to repeatedly capture high-quality image data across multiple positions. Finally, we analyzed single-cell Fv /Fm with the manufacturer-supplied software and PAMalysis, demonstrating a median difference <0.5% between both methods. We foresee that PACMan, and its auxiliary software package will help increase the experimental throughput in a range of microalgae studies currently relying on hand-operated MICROSCOPY-PAM technologies.
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Affiliation(s)
- Olle Pontén
- Department of Organismal Biology, Science for Life Laboratory, Uppsala University, Uppsala, Sweden
- School of Mathematics & Statistics, The University of Melbourne, Parkville, VIC, Australia
| | - Linhong Xiao
- Department of Organismal Biology, Science for Life Laboratory, Uppsala University, Uppsala, Sweden
| | - Jeanne Kutter
- Department of Organismal Biology, Science for Life Laboratory, Uppsala University, Uppsala, Sweden
| | - Yuan Cui
- Department of Organismal Biology, Science for Life Laboratory, Uppsala University, Uppsala, Sweden
| | - Carolina Wählby
- Department of Information Technology and Science for Life Laboratory, Uppsala University, Uppsala, Sweden
| | - Lars Behrendt
- Department of Organismal Biology, Science for Life Laboratory, Uppsala University, Uppsala, Sweden
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4
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Gupta A, Kang K, Pathania R, Saxton L, Saucedo B, Malik A, Torres-Tiji Y, Diaz CJ, Dutra Molino JV, Mayfield SP. Harnessing genetic engineering to drive economic bioproduct production in algae. Front Bioeng Biotechnol 2024; 12:1350722. [PMID: 38347913 PMCID: PMC10859422 DOI: 10.3389/fbioe.2024.1350722] [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: 12/05/2023] [Accepted: 01/16/2024] [Indexed: 02/15/2024] Open
Abstract
Our reliance on agriculture for sustenance, healthcare, and resources has been essential since the dawn of civilization. However, traditional agricultural practices are no longer adequate to meet the demands of a burgeoning population amidst climate-driven agricultural challenges. Microalgae emerge as a beacon of hope, offering a sustainable and renewable source of food, animal feed, and energy. Their rapid growth rates, adaptability to non-arable land and non-potable water, and diverse bioproduct range, encompassing biofuels and nutraceuticals, position them as a cornerstone of future resource management. Furthermore, microalgae's ability to capture carbon aligns with environmental conservation goals. While microalgae offers significant benefits, obstacles in cost-effective biomass production persist, which curtails broader application. This review examines microalgae compared to other host platforms, highlighting current innovative approaches aimed at overcoming existing barriers. These approaches include a range of techniques, from gene editing, synthetic promoters, and mutagenesis to selective breeding and metabolic engineering through transcription factors.
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Affiliation(s)
- Abhishek Gupta
- Mayfield Laboratory, Department of Molecular Biology, School of Biological Sciences, University of California San Diego, San Diego, CA, United States
| | - Kalisa Kang
- Mayfield Laboratory, Department of Molecular Biology, School of Biological Sciences, University of California San Diego, San Diego, CA, United States
| | - Ruchi Pathania
- Mayfield Laboratory, Department of Molecular Biology, School of Biological Sciences, University of California San Diego, San Diego, CA, United States
| | - Lisa Saxton
- Mayfield Laboratory, Department of Molecular Biology, School of Biological Sciences, University of California San Diego, San Diego, CA, United States
| | - Barbara Saucedo
- Mayfield Laboratory, Department of Molecular Biology, School of Biological Sciences, University of California San Diego, San Diego, CA, United States
| | - Ashleyn Malik
- Mayfield Laboratory, Department of Molecular Biology, School of Biological Sciences, University of California San Diego, San Diego, CA, United States
| | - Yasin Torres-Tiji
- Mayfield Laboratory, Department of Molecular Biology, School of Biological Sciences, University of California San Diego, San Diego, CA, United States
| | - Crisandra J. Diaz
- Mayfield Laboratory, Department of Molecular Biology, School of Biological Sciences, University of California San Diego, San Diego, CA, United States
| | - João Vitor Dutra Molino
- Mayfield Laboratory, Department of Molecular Biology, School of Biological Sciences, University of California San Diego, San Diego, CA, United States
| | - Stephen P. Mayfield
- Mayfield Laboratory, Department of Molecular Biology, School of Biological Sciences, University of California San Diego, San Diego, CA, United States
- California Center for Algae Biotechnology, University of California San Diego, San Diego, CA, United States
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5
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Chunzhuk EA, Grigorenko AV, Kiseleva SV, Chernova NI, Ryndin KG, Kumar V, Vlaskin MS. The Influence of Elevated CO 2 Concentrations on the Growth of Various Microalgae Strains. PLANTS (BASEL, SWITZERLAND) 2023; 12:2470. [PMID: 37447030 DOI: 10.3390/plants12132470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Revised: 06/22/2023] [Accepted: 06/26/2023] [Indexed: 07/15/2023]
Abstract
The influence of elevated CO2 concentrations on the growth and viability of various microalgae strains was studied. Arthrospira platensis, Chlorella ellipsoidea, Chlorella vulgaris, Gloeotila pulchra, and Elliptochloris subsphaerica were tested. The cultivation of microalgae was carried out at constant CO2 concentrations (0.04, 3, 6, or 9%-sequentially from lower to higher concentrations), under constant (24 h·day-1) illumination with an intensity of 74.3 µmol quanta·m-2·s-1, and a constant temperature of 23.5 ± 0.5 °C. The optical density of the microalgae biomass, pH, and the chemical composition of the culture medium were measured. Microscopy (including the cytochemical microscopic method) was conducted to monitor the state of the microalgae. The highest biomass growth rate (0.37 g·L-1·day-1), among all experiments, was achieved for Chlorella vulgaris at CO2 = 3% and for Chlorella ellipsoidea at CO2 = 6 and 9%. The lowest growth rate (0.12 g·L-1·day-1) was achieved for Arthrospira platensis at CO2 = 3 and 9%. The microscopy results showed the absence or a minimum number of dead cells of the strains under selected conditions. The ability to maintain the viability of cultures up to significant concentrations of CO2 = 9% was due to adaptation (gradual increase in CO2 concentrations in the experiments).
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Affiliation(s)
- Elizaveta A Chunzhuk
- Joint Institute for High Temperatures, Russian Academy of Sciences, 125412 Moscow, Russia
| | - Anatoly V Grigorenko
- Joint Institute for High Temperatures, Russian Academy of Sciences, 125412 Moscow, Russia
| | - Sophia V Kiseleva
- Joint Institute for High Temperatures, Russian Academy of Sciences, 125412 Moscow, Russia
| | - Nadezhda I Chernova
- Joint Institute for High Temperatures, Russian Academy of Sciences, 125412 Moscow, Russia
- Faculty of Geography, Lomonosov Moscow State University, 119991 Moscow, Russia
| | - Kirill G Ryndin
- Joint Institute for High Temperatures, Russian Academy of Sciences, 125412 Moscow, Russia
| | - Vinod Kumar
- Algal Research and Bioenergy Lab, Department of Food Science and Technology, Graphic Era (Deemed to Be University), Dehradun 248002, India
- Department of Environmental Safety and Product Quality Management, Peoples' Friendship University of Russia Named after Patrice Lumumba, 117198 Moscow, Russia
| | - Mikhail S Vlaskin
- Joint Institute for High Temperatures, Russian Academy of Sciences, 125412 Moscow, Russia
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6
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Sefbom J, Kremp A, Hansen PJ, Johannesson K, Godhe A, Rengefors K. Local adaptation through countergradient selection in northern populations of Skeletonema marinoi. Evol Appl 2023; 16:311-320. [PMID: 36793694 PMCID: PMC9923485 DOI: 10.1111/eva.13436] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Revised: 05/31/2022] [Accepted: 06/07/2022] [Indexed: 11/26/2022] Open
Abstract
Marine microorganisms have the potential to disperse widely with few obvious barriers to gene flow. However, among microalgae, several studies have demonstrated that species can be highly genetically structured with limited gene flow among populations, despite hydrographic connectivity. Ecological differentiation and local adaptation have been suggested as drivers of such population structure. Here we tested whether multiple strains from two genetically distinct Baltic Sea populations of the diatom Skeletonema marinoi showed evidence of local adaptation to their local environments: the estuarine Bothnian Sea and the marine Kattegat Sea. We performed reciprocal transplants of multiple strains between culture media based on water from the respective environments, and we also allowed competition between strains of estuarine and marine origin in both salinities. When grown alone, both marine and estuarine strains performed best in the high-salinity environment, and estuarine strains always grew faster than marine strains. This result suggests local adaptation through countergradient selection, that is, genetic effects counteract environmental effects. However, the higher growth rate of the estuarine strains appears to have a cost in the marine environment and when strains were allowed to compete, marine strains performed better than estuarine strains in the marine environment. Thus, other traits are likely to also affect fitness. We provide evidence that tolerance to pH could be involved and that estuarine strains that are adapted to a more fluctuating pH continue growing at higher pH than marine strains.
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Affiliation(s)
- Josefin Sefbom
- Department of Marine Sciences University of Gothenburg Gothenburg Sweden
| | - Anke Kremp
- Marine Research Centre Finnish Environment Institute (SYKE) Helsinki Finland.,Biological Oceanography Leibniz Institute for Baltic Sea Research Warnemünde Rostock Germany
| | - Per Juel Hansen
- Marine Biological Section University of Copenhagen Helsingør Denmark
| | - Kerstin Johannesson
- Department of Marine Sciences - Tjärnö University of Gothenburg Strömstad Sweden
| | - Anna Godhe
- Department of Marine Sciences University of Gothenburg Gothenburg Sweden
| | - Karin Rengefors
- Aquatic Ecology, Department of Biology Lund University Lund Sweden
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Chen Y, Liang H, Du H, Jesumani V, He W, Cheong KL, Li T, Hong T. Industry chain and challenges of microalgal food industry-a review. Crit Rev Food Sci Nutr 2022; 64:4789-4816. [PMID: 36377724 DOI: 10.1080/10408398.2022.2145455] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Currently, the whole world is facing hunger due to the increase in the global population and the rising level of food consumption. Unfortunately, the impact of environmental, climate, and political issues on agriculture has resulted in limited global food resources. Thus, it is important to develop new food sources that are environmentally friendly and not subject to climate or space limitations. Microalgae represent a potential source of nutrients and bioactive components for a wide range of high-value products. Advances in cultivation and genetic engineering techniques provide prospective approaches to widen their application for food. However, there are currently problems in the microalgae food industry in terms of assessing nutritional value, selecting processes for microalgae culture, obtaining suitable commercial strains of microalgae, etc. Additionally, the limitations of real data of market opportunities for microalgae make it difficult to assess their actual potential and to develop a better industrial chain. This review addresses the current status of the microalgae food industry, the process of commercializing microalgae food and breeding methods. Current research progress in addressing the limitations of microalgae industrialization and future prospects for developing microalgae food products are discussed.
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Affiliation(s)
- Yuanhao Chen
- Guangdong Provincial Key Laboratory of Marine Biotechnology, Department of Biology, College of Science, Shantou University, Shantou, Guangdong, China
- STU-UNIVPM Joint Algal Research Center, Institute of Marine Sciences, Shantou University, Shantou, Guangdong, China
- Guangdong Provincial Key Laboratory of Marine Disaster Prediction and Prevention, Shantou University, Shantou, Guangdong, China
| | - Honghao Liang
- Guangdong Provincial Key Laboratory of Marine Biotechnology, Department of Biology, College of Science, Shantou University, Shantou, Guangdong, China
- STU-UNIVPM Joint Algal Research Center, Institute of Marine Sciences, Shantou University, Shantou, Guangdong, China
- Guangdong Provincial Key Laboratory of Marine Disaster Prediction and Prevention, Shantou University, Shantou, Guangdong, China
| | - Hong Du
- Guangdong Provincial Key Laboratory of Marine Biotechnology, Department of Biology, College of Science, Shantou University, Shantou, Guangdong, China
- STU-UNIVPM Joint Algal Research Center, Institute of Marine Sciences, Shantou University, Shantou, Guangdong, China
- Guangdong Provincial Key Laboratory of Marine Disaster Prediction and Prevention, Shantou University, Shantou, Guangdong, China
| | - Valentina Jesumani
- Guangdong Provincial Key Laboratory of Marine Biotechnology, Department of Biology, College of Science, Shantou University, Shantou, Guangdong, China
| | - Weiling He
- Guangdong Provincial Key Laboratory of Marine Biotechnology, Department of Biology, College of Science, Shantou University, Shantou, Guangdong, China
- STU-UNIVPM Joint Algal Research Center, Institute of Marine Sciences, Shantou University, Shantou, Guangdong, China
- Guangdong Provincial Key Laboratory of Marine Disaster Prediction and Prevention, Shantou University, Shantou, Guangdong, China
| | - Kit-Leong Cheong
- Guangdong Provincial Key Laboratory of Marine Biotechnology, Department of Biology, College of Science, Shantou University, Shantou, Guangdong, China
| | - Tangcheng Li
- Guangdong Provincial Key Laboratory of Marine Biotechnology, Department of Biology, College of Science, Shantou University, Shantou, Guangdong, China
- STU-UNIVPM Joint Algal Research Center, Institute of Marine Sciences, Shantou University, Shantou, Guangdong, China
- Guangdong Provincial Key Laboratory of Marine Disaster Prediction and Prevention, Shantou University, Shantou, Guangdong, China
| | - Ting Hong
- Guangdong Provincial Key Laboratory of Marine Biotechnology, Department of Biology, College of Science, Shantou University, Shantou, Guangdong, China
- STU-UNIVPM Joint Algal Research Center, Institute of Marine Sciences, Shantou University, Shantou, Guangdong, China
- Guangdong Provincial Key Laboratory of Marine Disaster Prediction and Prevention, Shantou University, Shantou, Guangdong, China
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Random Mutagenesis as a Promising Tool for Microalgal Strain Improvement towards Industrial Production. Mar Drugs 2022; 20:md20070440. [PMID: 35877733 PMCID: PMC9318807 DOI: 10.3390/md20070440] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Revised: 06/27/2022] [Accepted: 06/27/2022] [Indexed: 02/06/2023] Open
Abstract
Microalgae have become a promising novel and sustainable feedstock for meeting the rising demand for food and feed. However, microalgae-based products are currently hindered by high production costs. One major reason for this is that commonly cultivated wildtype strains do not possess the robustness and productivity required for successful industrial production. Several strain improvement technologies have been developed towards creating more stress tolerant and productive strains. While classical methods of forward genetics have been extensively used to determine gene function of randomly generated mutants, reverse genetics has been explored to generate specific mutations and target phenotypes. Site-directed mutagenesis can be accomplished by employing different gene editing tools, which enable the generation of tailor-made genotypes. Nevertheless, strategies promoting the selection of randomly generated mutants avoid the introduction of foreign genetic material. In this paper, we review different microalgal strain improvement approaches and their applications, with a primary focus on random mutagenesis. Current challenges hampering strain improvement, selection, and commercialization will be discussed. The combination of these approaches with high-throughput technologies, such as fluorescence-activated cell sorting, as tools to select the most promising mutants, will also be discussed.
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9
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Theodosiou E, Tüllinghoff A, Toepel J, Bühler B. Exploitation of Hetero- and Phototrophic Metabolic Modules for Redox-Intensive Whole-Cell Biocatalysis. Front Bioeng Biotechnol 2022; 10:855715. [PMID: 35497353 PMCID: PMC9043136 DOI: 10.3389/fbioe.2022.855715] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2022] [Accepted: 03/09/2022] [Indexed: 11/13/2022] Open
Abstract
The successful realization of a sustainable manufacturing bioprocess and the maximization of its production potential and capacity are the main concerns of a bioprocess engineer. A main step towards this endeavor is the development of an efficient biocatalyst. Isolated enzyme(s), microbial cells, or (immobilized) formulations thereof can serve as biocatalysts. Living cells feature, beside active enzymes, metabolic modules that can be exploited to support energy-dependent and multi-step enzyme-catalyzed reactions. Metabolism can sustainably supply necessary cofactors or cosubstrates at the expense of readily available and cheap resources, rendering external addition of costly cosubstrates unnecessary. However, for the development of an efficient whole-cell biocatalyst, in depth comprehension of metabolic modules and their interconnection with cell growth, maintenance, and product formation is indispensable. In order to maximize the flux through biosynthetic reactions and pathways to an industrially relevant product and respective key performance indices (i.e., titer, yield, and productivity), existing metabolic modules can be redesigned and/or novel artificial ones established. This review focuses on whole-cell bioconversions that are coupled to heterotrophic or phototrophic metabolism and discusses metabolic engineering efforts aiming at 1) increasing regeneration and supply of redox equivalents, such as NAD(P/H), 2) blocking competing fluxes, and 3) increasing the availability of metabolites serving as (co)substrates of desired biosynthetic routes.
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Affiliation(s)
- Eleni Theodosiou
- Institute of Applied Biosciences, Centre for Research and Technology Hellas, Thessaloniki, Greece
| | - Adrian Tüllinghoff
- Department of Solar Materials, Helmholtz Centre for Environmental Research GmbH—UFZ, Leipzig, Germany
| | - Jörg Toepel
- Department of Solar Materials, Helmholtz Centre for Environmental Research GmbH—UFZ, Leipzig, Germany
| | - Bruno Bühler
- Department of Solar Materials, Helmholtz Centre for Environmental Research GmbH—UFZ, Leipzig, Germany
- *Correspondence: Bruno Bühler,
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10
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Inagaki N. Processing of D1 Protein: A Mysterious Process Carried Out in Thylakoid Lumen. Int J Mol Sci 2022; 23:ijms23052520. [PMID: 35269663 PMCID: PMC8909930 DOI: 10.3390/ijms23052520] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Revised: 02/16/2022] [Accepted: 02/21/2022] [Indexed: 11/16/2022] Open
Abstract
In oxygenic photosynthetic organisms, D1 protein, a core subunit of photosystem II (PSII), displays a rapid turnover in the light, in which D1 proteins are distinctively damaged and immediately removed from the PSII. In parallel, as a repair process, D1 proteins are synthesized and simultaneously assembled into the PSII. On this flow, the D1 protein is synthesized as a precursor with a carboxyl-terminal extension, and the D1 processing is defined as a step for proteolytic removal of the extension by a specific protease, CtpA. The D1 processing plays a crucial role in appearance of water-oxidizing capacity of PSII, because the main chain carboxyl group at carboxyl-terminus of the D1 protein, exposed by the D1 processing, ligates a manganese and a calcium atom in the Mn4CaO5-cluster, a special equipment for water-oxidizing chemistry of PSII. This review focuses on the D1 processing and discusses it from four angles: (i) Discovery of the D1 processing and recognition of its importance: (ii) Enzyme involved in the D1 processing: (iii) Efforts for understanding significance of the D1 processing: (iv) Remaining mysteries in the D1 processing. Through the review, I summarize the current status of our knowledge on and around the D1 processing.
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Affiliation(s)
- Noritoshi Inagaki
- Research Center for Advanced Analysis, National Agriculture and Food Research Organization (NARO), Tsukuba 305-8518, Japan
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