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Perozeni F, Baier T. Current Nuclear Engineering Strategies in the Green Microalga Chlamydomonas reinhardtii. Life (Basel) 2023; 13:1566. [PMID: 37511941 PMCID: PMC10381326 DOI: 10.3390/life13071566] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 07/07/2023] [Accepted: 07/13/2023] [Indexed: 07/30/2023] Open
Abstract
The green model microalga Chlamydomonas reinhardtii recently emerged as a sustainable production chassis for the efficient biosynthesis of recombinant proteins and high-value metabolites. Its capacity for scalable, rapid and light-driven growth in minimal salt solutions, its simplicity for genetic manipulation and its "Generally Recognized As Safe" (GRAS) status are key features for its application in industrial biotechnology. Although nuclear transformation has typically resulted in limited transgene expression levels, recent developments now allow the design of powerful and innovative bioproduction concepts. In this review, we summarize the main obstacles to genetic engineering in C. reinhardtii and describe all essential aspects in sequence adaption and vector design to enable sufficient transgene expression from the nuclear genome. Several biotechnological examples of successful engineering serve as blueprints for the future establishment of C. reinhardtii as a green cell factory.
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Affiliation(s)
- Federico Perozeni
- Department of Biotechnology, University of Verona, 37134 Verona, Italy
| | - Thomas Baier
- Algae Biotechnology and Bioenergy, Faculty of Biology, Center for Biotechnology (CeBiTec), Bielefeld University, 33615 Bielefeld, Germany
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2
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Cui Y, Wang K, Xu W, Wang Y, Gao Z, Cui H, Meng C, Qin S. Plastid Engineering of a Marine Alga, Nannochloropsis gaditana, for Co-Expression of Two Recombinant Peptides. JOURNAL OF PHYCOLOGY 2021; 57:569-576. [PMID: 33174215 DOI: 10.1111/jpy.13099] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Revised: 10/16/2020] [Accepted: 10/28/2020] [Indexed: 06/11/2023]
Abstract
The purpose of this study was to establish a plastid transformation system for expressing recombinant proteins in Nannochloropsis gaditana. On the basis of the sequenced plastid genome, the homologous flanking region, 16S-trnI/trnA-23S, and the endogenous regulatory fragments containing the psbA promoter, rbcL promoter, rbcL terminator, and psbA terminator were amplified from N. gaditana as elements of a plastid transformation vector. Then, the herbicide-resistant gene (bar) was used as a selectable marker, regulated by the psbA promoter and rbcL terminator. Finally, two codon-optimized antimicrobial peptide-coding genes linked by endogenous ribosome binding site (RBS) in a polycistron were inserted into the constructed vector under the regulation of the rbcL promoter and psbA terminator. After microparticle bombardment, the positive clones were detected using polymerase chain reaction (PCR), and Southern and Western blotting were used to assess the co-expression of the two antimicrobial peptides from the plastid. Nannochloropsis gaditana showed the potential to express recombinant proteins for biotechnological applications, for example, for the development of oral vaccines in aquaculture.
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Affiliation(s)
- Yulin Cui
- Key Laboratory of Coastal Biology and Biological Resource Utilization, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, 264003, China
- Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao, 266071, China
| | - Kang Wang
- School of Life Sciences, Shandong University of Technology, Zibo, 255049, China
| | - Wenxin Xu
- Institute of Molecular Agriculture and Bioenergy, Shanxi Agricultural University, Taigu, 030801, China
| | - Yinchu Wang
- Key Laboratory of Coastal Biology and Biological Resource Utilization, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, 264003, China
- Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao, 266071, China
| | - Zhengquan Gao
- School of Life Sciences, Shandong University of Technology, Zibo, 255049, China
| | - Hongli Cui
- Institute of Molecular Agriculture and Bioenergy, Shanxi Agricultural University, Taigu, 030801, China
| | - Chunxiao Meng
- School of Life Sciences, Shandong University of Technology, Zibo, 255049, China
| | - Song Qin
- Key Laboratory of Coastal Biology and Biological Resource Utilization, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, 264003, China
- Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao, 266071, China
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Zhang MP, Wang M, Wang C. Nuclear transformation of Chlamydomonas reinhardtii: A review. Biochimie 2020; 181:1-11. [PMID: 33227342 DOI: 10.1016/j.biochi.2020.11.016] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2020] [Revised: 06/14/2020] [Accepted: 11/17/2020] [Indexed: 10/22/2022]
Abstract
Chlamydomonas reinhardtii is a model organism with three sequenced genomes capable of genetic transformation. C. reinhardtii has the advantages of being low cost, non-toxic, and having a post-translational modification system that ensures the recombinant proteins have the same activity as natural proteins, thus making it a great platform for application in molecular biology and other fields. In this review, we summarize the existing methods for nuclear transformation of C. reinhardtii, genes for selection, examples of foreign protein expression, and factors affecting transformation efficiency, to provide insights into effective strategies for the nuclear transformation of C. reinhardtii.
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Affiliation(s)
- Meng-Ping Zhang
- College of Biotechnology, Sichuan University of Science and Engineering, Zigong, 643000, Sichuan province, China
| | - Mou Wang
- College of Biotechnology, Sichuan University of Science and Engineering, Zigong, 643000, Sichuan province, China
| | - Chuan Wang
- College of Biotechnology, Sichuan University of Science and Engineering, Zigong, 643000, Sichuan province, China.
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EL-Sheekh MM, Almutairi AW, Touliabah HE. Construction of a novel vector for the nuclear transformation of the unicellular green alga Chlamydomonas reinhardtii and its stable expression. JOURNAL OF TAIBAH UNIVERSITY FOR SCIENCE 2019. [DOI: 10.1080/16583655.2019.1603574] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
| | - Adel W. Almutairi
- Rabigh –Faculty of Science & Arts, Biological Sciences Derpartment, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Hussein E. Touliabah
- Rabigh –Faculty of Science & Arts, Biological Sciences Derpartment, King Abdulaziz University, Jeddah, Saudi Arabia
- Faculty of Science, Arts and Education for Womens, Botany Department, Ain Shams University, Cairo, Egypt
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Lin H, Shen H, Lee YK. Cellular and Molecular Responses of Dunaliella tertiolecta by Expression of a Plant Medium Chain Length Fatty Acid Specific Acyl-ACP Thioesterase. Front Microbiol 2018; 9:619. [PMID: 29670594 PMCID: PMC5893845 DOI: 10.3389/fmicb.2018.00619] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2017] [Accepted: 03/16/2018] [Indexed: 01/18/2023] Open
Abstract
Metabolic engineering of microalgae to accumulate high levels of medium chain length fatty acids (MCFAs) has met with limited success. Traditional approaches employ single introduction of MCFA specific acyl-ACP thioesterases (TEs), but our current research in transgenic Dunaliella tertiolecta line has highlighted that, there is no single rate-limiting approach that can effectively increase MCFA levels. Here, we explore the accumulation of MCFAs in D. tertiolecta after transgenic expression of myristic acid biased TE (C14TE). We observe that the MCFA levels were negatively correlated to the fatty acid (FA) synthesis genes, ketoacyl-ACP synthase II (KASII), stearoyl-CoA-9-desaturase (Δ9D), and oleoyl-CoA-12-desaturase (Δ12D). To further examine the molecular mechanism of MCFA accumulation in microalgae, we investigate the transcriptomic dynamics of the MCFA producing strain of D. tertiolecta. At the transcript level, enhanced MCFA accumulation primarily involved up-regulation of photosynthetic genes and down-regulation of genes from central carbon metabolic processes, resulting in an overall decrease in carbon precursors for FA synthesis. We additionally observe that MCFA specific peroxisomal β-oxidation gene (ACX3) was greatly enhanced to prevent excessive build-up of unusual MCFA levels. Besides, long chain acyl-CoA synthetase gene (LACS) was down-regulated, likely in attempt to control fatty acyl supply flux to FA synthesis cycle. This article provides a spatial regulation model of unusual FA accumulation in microalgae and a platform for additional metabolic engineering targeting pathways from FA synthesis, FA transport, and peroxisomal β-oxidation to achieve microalgae oils with higher levels of MCFAs.
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Affiliation(s)
- Huixin Lin
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Hui Shen
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Yuan K Lee
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
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Lin H, Lee YK. Genetic engineering of medium-chain-length fatty acid synthesis in Dunaliella tertiolecta for improved biodiesel production. JOURNAL OF APPLIED PHYCOLOGY 2017; 29:2811-2819. [PMID: 29213182 PMCID: PMC5705751 DOI: 10.1007/s10811-017-1210-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/17/2017] [Revised: 06/22/2017] [Accepted: 06/22/2017] [Indexed: 06/07/2023]
Abstract
Genetic engineering of microalgae to accumulate high levels of medium-chain-length fatty acids (MCFAs) represents an attractive strategy to improve the quality of microalgae-based biodiesel, but it has thus far been least successful. We demonstrate that one limitation is the availability of fatty acyl-acyl carrier protein (ACP) substrate pool for acyl-ACP thioesterase (TE). A combinational expression platform that involved plant lauric acid-biased TE (C12TE) and MCFA-specific ketoacyl-ACP synthase (KASIV) increased lauric acid (C12:0) and myristic acid (C14:0) accumulation by almost sevenfold and fourfold, respectively, compared with native strain. These findings suggest a platform for further investigation into the enlargement of MCFA acyl-ACP substrate pool as an approach to sustainably improve quality of microalgae-based biodiesel with regard to MCFA production.
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Affiliation(s)
- Huixin Lin
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Block MD4, 5 Science Drive 2, Singapore, 117545 Singapore
| | - Yuan Kun Lee
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Block MD4, 5 Science Drive 2, Singapore, 117545 Singapore
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Tan KWM, Lee YK. Expression of the heterologous Dunaliella tertiolecta fatty acyl-ACP thioesterase leads to increased lipid production in Chlamydomonas reinhardtii. J Biotechnol 2017; 247:60-67. [PMID: 28279815 DOI: 10.1016/j.jbiotec.2017.03.004] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Revised: 03/03/2017] [Accepted: 03/04/2017] [Indexed: 12/22/2022]
Abstract
Biofuel production from genetically-engineered microalgae is currently among the most widely studied strategies in generating renewable energy. However, microalgae currently suffer from low oil yields which limit the commercial feasibility of industrial-scale production. A major bottleneck in cost-efficient biofuel production from microalgae is the dilemma between biomass productivity and lipid accumulation. When grown under stressful culture conditions such as nitrogen depletion, microalgae accumulate large amounts of neutral lipids, but it comes at the expense of growth which negatively impacts overall lipid productivity. Overexpression of acyl-ACP thioesterases (TE) had been successful in increasing the production of fatty acids (FA) in prokaryotes such as E. coli and cyanobacteria, but has not been effectively tested in microalgae. In this study, we introduced a TE from D. tertiolecta (DtTE) into C. reinhardtii to investigate its effects on FA production without compromising growth. The results indicate that C. reinhardtii transformants were able to produce 63 and 94% more neutral lipids than the wild-type, which translates to an approximately 56% improvement in total lipids, without compromising growth. These findings demonstrate the cross-species functionality of TE, and provide a platform for further studies into using TE as a strategy to increase biofuel production from microalgae.
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Affiliation(s)
- Kenneth Wei Min Tan
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117545
| | - Yuan Kun Lee
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117545.
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Simon DP, Anila N, Gayathri K, Sarada R. Heterologous expression of β-carotene hydroxylase in Dunaliella salina by Agrobacterium -mediated genetic transformation. ALGAL RES 2016. [DOI: 10.1016/j.algal.2016.06.017] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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Anila N, Simon DP, Chandrashekar A, Ravishankar GA, Sarada R. Metabolic engineering of Dunaliella salina for production of ketocarotenoids. PHOTOSYNTHESIS RESEARCH 2016; 127:321-33. [PMID: 26334599 DOI: 10.1007/s11120-015-0188-8] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2014] [Accepted: 08/25/2015] [Indexed: 05/09/2023]
Abstract
Dunaliella is a commercially important marine alga producing high amount of β-carotene. The use of Dunaliella as a potential transgenic system for the production of recombinant proteins has been recently recognized. The present study reports for the first time the metabolic engineering of carotenoid biosynthesis in Dunaliella salina for ketocarotenoid production. The pathway modification included the introduction of a bkt gene from H. pluvialis encoding β-carotene ketolase (4,4'β-oxygenase) along with chloroplast targeting for the production of ketocarotenoids. The bkt under the control of Dunaliella Rubisco smaller subunit promoter along with its transit peptide sequence was introduced into the alga through standardized Agrobacterium-mediated transformation procedure. The selected transformants were confirmed using GFP and GUS expression, PCR and southern blot analysis. A notable upregulation of the endogenous hydroxylase level of transformants was observed where the BKT expression was higher in nutrient-limiting conditions. Carotenoid analysis of the transformants through HPLC and MS analysis showed the presence of astaxanthin and canthaxanthin with maximum content of 3.5 and 1.9 µg/g DW, respectively. The present study reports the feasibility of using D. salina for the production of ketocarotenoids including astaxanthin.
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Affiliation(s)
- N Anila
- Department of Botany, St. Xavier's College For Women (Affiliated to Mahatma Gandhi University), Aluva, 683101, India
| | - Daris P Simon
- Plant Cell Biotechnology Department, Central Food Technological Research Institute (A Constituent Laboratory of the Council of Scientific and Industrial Research, CSIR), Mysore, Karnataka, 570 020, India
| | - Arun Chandrashekar
- Bhat Bio-Tech India (P) Ltd., 11-A, 4th Cross Veerasandra Industrial Area Electronics City, Bangalore, 561221, India
| | - G A Ravishankar
- Dr. C. D. Sagar Center for Life Sciences, Dayanada Sagar Institutions, Bangalore, 560008, India
| | - R Sarada
- Plant Cell Biotechnology Department, Central Food Technological Research Institute (A Constituent Laboratory of the Council of Scientific and Industrial Research, CSIR), Mysore, Karnataka, 570 020, India.
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Doron L, Segal N, Shapira M. Transgene Expression in Microalgae-From Tools to Applications. FRONTIERS IN PLANT SCIENCE 2016; 7:505. [PMID: 27148328 PMCID: PMC4840263 DOI: 10.3389/fpls.2016.00505] [Citation(s) in RCA: 92] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Accepted: 03/29/2016] [Indexed: 05/17/2023]
Abstract
Microalgae comprise a biodiverse group of photosynthetic organisms that reside in water sources and sediments. The green microalgae Chlamydomonas reinhardtii was adopted as a useful model organism for studying various physiological systems. Its ability to grow under both photosynthetic and heterotrophic conditions allows efficient growth of non-photosynthetic mutants, making Chlamydomonas a useful genetic tool to study photosynthesis. In addition, this green alga can grow as haploid or diploid cells, similar to yeast, providing a powerful genetic system. As a result, easy and efficient transformation systems have been developed for Chlamydomonas, targeting both the chloroplast and nuclear genomes. Since microalgae comprise a rich repertoire of species that offer variable advantages for biotech and biomed industries, gene transfer technologies were further developed for many microalgae to allow for the expression of foreign proteins of interest. Expressing foreign genes in the chloroplast enables the targeting of foreign DNA to specific sites by homologous recombination. Chloroplast transformation also allows for the introduction of genes encoding several enzymes from a complex pathway, possibly as an operon. Expressing foreign proteins in the chloroplast can also be achieved by introducing the target gene into the nuclear genome, with the protein product bearing a targeting signal that directs import of the transgene-product into the chloroplast, like other endogenous chloroplast proteins. Integration of foreign genes into the nuclear genome is mostly random, resulting in large variability between different clones, such that extensive screening is required. The use of different selection modalities is also described, with special emphasis on the use of herbicides and metabolic markers which are considered to be friendly to the environment, as compared to drug-resistance genes that are commonly used. Finally, despite the development of a wide range of transformation tools and approaches, expression of foreign genes in microalgae suffers from low efficiency. Thus, novel tools have appeared in recent years to deal with this problem. Finally, while C. reinhardtii was traditionally used as a model organism for the development of transformation systems and their subsequent improvement, similar technologies can be adapted for other microalgae that may have higher biotechnological value.
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The potential of transgenic green microalgae; a robust photobioreactor to produce recombinant therapeutic proteins. World J Microbiol Biotechnol 2014; 30:2783-96. [PMID: 25115849 DOI: 10.1007/s11274-014-1714-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2013] [Accepted: 07/30/2014] [Indexed: 02/01/2023]
Abstract
Microalgae have been used in food, cosmetic, and biofuel industries as a natural source of lipids, vitamins, pigments and antioxidants for a long time. Green microalgae, as potent photobioreactors, can be considered as an economical expression system to produce recombinant therapeutical proteins at large-scale due to low cost of production and scaling-up capitalization owning to the inexpensive medium requirement, fast growth rate, and the ease of manipulation. These microalgae possess all benefit eukaryotic expression systems including the ability of post-translational modifications required for proper folding and stability of active proteins. Among the many items regarded as recombinant protein production, this review compares the different expression systems with green microalgae like Dunaliella by viewing the nuclear/chloroplast transformation challenges/benefits, related selection markers/reporter genes, and crucial factors/strategies affecting the increase of foreign protein expression in microalgae transformants. Some important factors were discussed regarding the increase of protein yielding in microalgae transformants including: transformation-associated genotypic modifications, endogenous regulatory factors, promoters, codon optimization, enhancer elements, and milking of recombinant protein.
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Díaz-Santos E, de la Vega M, Vila M, Vigara J, León R. Efficiency of different heterologous promoters in the unicellular microalgaChlamydomonas reinhardtii. Biotechnol Prog 2013; 29:319-28. [DOI: 10.1002/btpr.1690] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2012] [Revised: 12/27/2012] [Indexed: 01/27/2023]
Affiliation(s)
- Encarnación Díaz-Santos
- Lab Bioquímica y Biología Molecular. Departamento de Química y Ciencia de Materiales, Facultad de Ciencias Experimentales; Universidad de Huelva; Avda. Fuerzas Armadas s/n 21007 Huelva Spain
| | - Marta de la Vega
- Lab Bioquímica y Biología Molecular. Departamento de Química y Ciencia de Materiales, Facultad de Ciencias Experimentales; Universidad de Huelva; Avda. Fuerzas Armadas s/n 21007 Huelva Spain
| | - Marta Vila
- Lab Bioquímica y Biología Molecular. Departamento de Química y Ciencia de Materiales, Facultad de Ciencias Experimentales; Universidad de Huelva; Avda. Fuerzas Armadas s/n 21007 Huelva Spain
| | - Javier Vigara
- Lab Bioquímica y Biología Molecular. Departamento de Química y Ciencia de Materiales, Facultad de Ciencias Experimentales; Universidad de Huelva; Avda. Fuerzas Armadas s/n 21007 Huelva Spain
| | - Rosa León
- Lab Bioquímica y Biología Molecular. Departamento de Química y Ciencia de Materiales, Facultad de Ciencias Experimentales; Universidad de Huelva; Avda. Fuerzas Armadas s/n 21007 Huelva Spain
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Georgianna DR, Hannon MJ, Marcuschi M, Wu S, Botsch K, Lewis AJ, Hyun J, Mendez M, Mayfield SP. Production of recombinant enzymes in the marine alga Dunaliella tertiolecta. ALGAL RES 2013. [DOI: 10.1016/j.algal.2012.10.004] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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Vila M, Díaz-Santos E, de la Vega M, Rodríguez H, Vargas A, León R. Promoter trapping in microalgae using the antibiotic paromomycin as selective agent. Mar Drugs 2012; 10:2749-65. [PMID: 23211713 PMCID: PMC3528124 DOI: 10.3390/md10122749] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2012] [Revised: 10/12/2012] [Accepted: 11/15/2012] [Indexed: 11/16/2022] Open
Abstract
The lack of highly active endogenous promoters to drive the expression of transgenes is one of the main drawbacks to achieving efficient transformation of many microalgal species. Using the model chlorophyte Chlamydomonas reinhardtii and the paromomycin resistance APHVIII gene from Streptomyces rimosus as a marker, we have demonstrated that random insertion of the promoterless marker gene and subsequent isolation of the most robust transformants allows for the identification of novel strong promoter sequences in microalgae. Digestion of the genomic DNA with an enzyme that has a unique restriction site inside the marker gene and a high number of target sites in the genome of the microalga, followed by inverse PCR, allows for easy determination of the genomic region, which precedes the APHVIII marker gene. In most of the transformants analyzed, the marker gene is inserted in intragenic regions and its expression relies on its adequate insertion in frame with native genes. As an example, one of the new promoters identified was used to direct the expression of the APHVIII marker gene in C. reinhardtii, showing high transformation efficiencies.
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Affiliation(s)
- Marta Vila
- Biochemistry Laboratory, Experimental Sciences Faculty, University of Huelva, Huelva 27071, Spain
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Thanh T, Chi VTQ, Omar H, Abdullah MP, Napis S. Sequence analysis and potentials of the native RbcS promoter in the development of an alternative eukaryotic expression system using green Microalga Ankistrodesmus convolutus. Int J Mol Sci 2012; 13:2676-2691. [PMID: 22489117 PMCID: PMC3317680 DOI: 10.3390/ijms13032676] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2011] [Revised: 02/02/2012] [Accepted: 02/05/2012] [Indexed: 12/17/2022] Open
Abstract
The availability of highly active homologous promoters is critical in the development of a transformation system and improvement of the transformation efficiency. To facilitate transformation of green microalga Ankistrodesmus convolutus which is considered as a potential candidate for many biotechnological applications, a highly-expressed native promoter sequence of ribulose-1,5-bisphosphate carboxylase/oxygenase small subunit (AcRbcS) has been used to drive the expression of β-glucuronidase (gusA) gene in this microalga. Besides the determination of the transcription start site by 5'-RACE, sequence analysis revealed that AcRbcS promoter contained consensus TATA-box and several putative cis-acting elements, including some representative light-regulatory elements (e.g., G-box, Sp1 motif and SORLIP2), which confer light responsiveness in plants, and several potential conserved motifs (e.g., CAGAC-motif, YCCYTGG-motifs and CACCACA-motif), which may be involved in light responsiveness of RbcS gene in green microalgae. Using AcRbcS promoter::gusA translational fusion, it was demonstrated that this promoter could function as a light-regulated promoter in transgenic A. convolutus, which suggested that the isolated AcRbcS promoter was a full and active promoter sequence that contained all cis-elements required for developmental and light-mediated control of gene expression, and this promoter can be used to drive the expression of heterologous genes in A. convolutus. This achievement therefore advances the development of A. convolutus as an alternative expression system for the production of recombinant proteins. This is the first report on development of gene manipulation system for unicellular green alga A. convolutus.
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Affiliation(s)
| | | | | | | | - Suhaimi Napis
- Author to whom correspondence should be addressed; E-Mail: or ; Tel.: +603-8947-1207; Fax: +603-8948-3514
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Cloning and characterization of ribulose-1,5-bisphosphate carboxylase/oxygenase small subunit (RbcS) cDNA from green microalga Ankistrodesmus convolutus. Mol Biol Rep 2011; 38:5297-305. [PMID: 21287365 DOI: 10.1007/s11033-011-0679-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2010] [Accepted: 01/10/2011] [Indexed: 10/18/2022]
Abstract
An initial study on gene cloning and characterization of unicellular green microalga Ankistrodesmus convolutus was carried out to isolate and characterize the full-length cDNA of ribulose-1,5-bisphosphate carboxylase/oxygenase small subunit (RbcS) as a first step towards elucidating the structure of A. convolutus RbcS gene. The full-length of A. convolutus RbcS cDNA (AcRbcS) contained 28 bp of 5' untranslated region (UTR), 225 bp of 3' non-coding region, and an open reading frame of 165 amino acids consisting of a chloroplast transit peptide with 24 amino acids and a mature protein of 141 amino acids. The amino acid sequence has high identity to those of other green algae RbcS genes. The AcRbcS contained a few conserved domains including protein kinase C phosphorylation site, tyrosine kinase phosphorylation site and N-myristoylation sites. The AcRbcS was successfully expressed in Escherichia coli and a ~21 kDa of anticipated protein band was observed on SDS-PAGE. From the phylogenetic analysis of RbcS protein sequences, it was found that the RbcS of A. convolutus has closer genetic relationship with green microalgae species compared to those of green seaweed and green macroalgae species. Southern hybridization analysis revealed that the AcRbcS is a member of a small multigene family comprising of two to six members in A. convolutus genome. Under different illumination conditions, RT-PCR analysis showed that AcRbcS transcription was reduced in the dark, and drastically recovered in the light condition. Results presented in this paper established a good foundation for further study on the photosynthetic process of A. convolutus and other green algae species where little information is known on Rubisco small subunit.
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Nuclear transformation of eukaryotic microalgae: historical overview, achievements and problems. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2008; 616:1-11. [PMID: 18161486 DOI: 10.1007/978-0-387-75532-8_1] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Transformation of microalgae is a first step in their use for biotechnological applications involving foreign protein production or molecular modifications of specific cell metabolic pathways. Since the first reliable achievements of nuclear transformation in Chlamydomonas, other eukaryotic microalgae have become transformed with molecular markers that allow a direct selection. Different methods--glass beads, electroporation, particle bombardment, or Agrobacterium--and constructions have been set up in several organisms and successfully used. However, some problems associated with efficiency, integration, or stability of the transgenes still persist and are analysed herein. Though the number of microalgae species successfully transformed is not very high, prospects for transformation of many more are good enough on the basis of what has been achieved so far.
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Hirakawa Y, Kofuji R, Ishida KI. TRANSIENT TRANSFORMATION OF A CHLORARACHNIOPHYTE ALGA, LOTHARELLA AMOEBIFORMIS (CHLORARACHNIOPHYCEAE), WITH uidA AND egfp REPORTER GENES(1). JOURNAL OF PHYCOLOGY 2008; 44:814-20. [PMID: 27041439 DOI: 10.1111/j.1529-8817.2008.00513.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
A transient genetic transformation system was established for a chlorarachniophyte alga, Lotharella amoebiformis K. Ishida et Y. Hara. We first isolated sequences that contain a putative promoter for a RUBISCO SSU (rbcS) gene and a terminator for another copy of rbcS gene from L. amoebiformis. With those promoter and terminator sequences, we developed two expression vectors, pLaRGus and pLaRGfp, which code uidA and egfp genes, respectively. The cells were then transformed with each vector using a microparticle bombardment system. When the cells were transformed with the pLaRGus, β-glucuronidase (GUS) staining dyed several cells blue. Green fluorescent protein (GFP) fluorescence was observed in the cells transformed with pLaRGfp. The highest transient transformation efficiency, 35 per 2 × 10(7) cells, was detected from the GUS staining. This study demonstrates that two reporter genes are expressed in L. amoebiformis cells when rbcS promoter and terminator are used. The conditions of transformation were also optimized. This is the first report of successful genetic transformation in chlorarachniophyte algae.
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Affiliation(s)
- Yoshihisa Hirakawa
- Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1, Tennodai, Tsukuba 305-8572, JapanDivision of Life Sciences, Graduate School of Natural Science and Technology, Kanazawa University, Kakuma, Kanazawa 920-1192, JapanGraduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1, Tennodai, Tsukuba 305-8572, Japan
| | - Rumiko Kofuji
- Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1, Tennodai, Tsukuba 305-8572, JapanDivision of Life Sciences, Graduate School of Natural Science and Technology, Kanazawa University, Kakuma, Kanazawa 920-1192, JapanGraduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1, Tennodai, Tsukuba 305-8572, Japan
| | - Ken-Ichiro Ishida
- Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1, Tennodai, Tsukuba 305-8572, JapanDivision of Life Sciences, Graduate School of Natural Science and Technology, Kanazawa University, Kakuma, Kanazawa 920-1192, JapanGraduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1, Tennodai, Tsukuba 305-8572, Japan
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Thomas-Hall S, Campbell PR, Carlens K, Kawanishi E, Swennen R, Sági L, Schenk PM. Phylogenetic and molecular analysis of the ribulose-1,5-bisphosphate carboxylase small subunit gene family in banana. JOURNAL OF EXPERIMENTAL BOTANY 2007; 58:2685-97. [PMID: 17584952 DOI: 10.1093/jxb/erm129] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Despite being the number one fruit crop in the world, very little is known about the phylogeny and molecular biology of banana (Musa spp.). Six banana rbcS gene families encoding the small subunit of ribulose-1,5-bisphosphate carboxylase/oxygenase from six different Musa spp. are presented. For a comprehensive phylogenetic study using Musa rbcS genes, a total of 57 distinct rbcS sequences was isolated from six accessions that contained different combinations of the A and B ancestral/parental genomes. As a result, five of the six members of the rbcS gene family could be affiliated with the A and/or B Musa genomes and at least three of the six gene families most likely existed before Musa A and B genomes separated. By combining sequence data with quantitative real-time PCR it was determined that the different Musa rbcS gene family members are also often multiply represented in each genome, with the highest copy numbers in the B genome. Expression of some of the rbcS genes varied in intensity and in different tissues indicating differences in regulation. To analyse and compare regulatory sequences of Musa rbcS genes, promoter and terminator regions were cloned for three Musa rbcS genes. Transient transformation assays using promoter-reporter-terminator constructs in maize, wheat, and sugarcane demonstrated that the rbcS-Ma1, rbcS-Ma3, and rbcS-Ma5 promoters could be useful for transgene expression in heterologous expression systems. Furthermore, the rbcS-Ma1 terminator resulted in a 2-fold increase of transgene expression when directly compared with the widely used Nos terminator.
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Affiliation(s)
- Skye Thomas-Hall
- School of Integrative Biology, The University of Queensland, St Lucia, Queensland, Australia
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Sun Y, Gao X, Li Q, Zhang Q, Xu Z. Functional complementation of a nitrate reductase defective mutant of a green alga Dunaliella viridis by introducing the nitrate reductase gene. Gene 2006; 377:140-9. [PMID: 16797881 DOI: 10.1016/j.gene.2006.03.018] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2005] [Revised: 03/03/2006] [Accepted: 03/28/2006] [Indexed: 11/21/2022]
Abstract
Nitrate reductase (NR) catalyzes NAD (P) H dependent reduction of nitrate to nitrite. Transformation systems have been established in several species of green algae by nitrate reductase gene functional complementation. In this report, an endogenous NR cDNA (3.4 kb) and a genomic fragment (14.6 kb) containing the NR gene (DvNIA1) were isolated from the D. viridis cDNA and genomic libraries respectively. Southern blot and Northern blot analyses showed that this gene exists as a single copy in D. viridis and is induced by nitrate. To obtain a NR defective mutant as a recipient strain, D. viridis cells were treated with a chemical mutagen and then cultured on a chlorate-containing plate to enrich chlorate tolerant mutants. Southern analysis showed that one isolate, B14, had a deletion in the DvNIA1 gene region. Using electroporation conditions determined in this laboratory, plasmid pDVNR containing the intact DvNIA1 gene has been electroporated into the defective mutant B14. Strains retaining a nitrate assimilation phenotype were obtained from nitrate plates after spreading the electroporated cells. In some individual strains, transcription of the introduced gene was detected. NR activity in these strains was slightly higher than that in the defective B14 cell, but excretion of nitrite into culture media was almost as high as that of the wild-type cell. Possible episomal presence of the introduced DNA in D. viridis is discussed.
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Affiliation(s)
- Yu Sun
- Institute of Plant Physiology and Ecology, Shanghai Institute for Biological Sciences, The Chinese Academy of Science, Shanghai, People's Republic of China
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