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Illustration of various genetic-engineering strategies used in microalgae to improve (A) photosynthetic efficiency and biomass production, (B) value-added product synthesis, and (C) lipid production.
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Microalgae, due to their complex metabolic capacity, are being continuously explored for nutraceuticals, pharmaceuticals, and other industrially important bioactives. However, suboptimal yield and productivity of the bioactive of interest in local and robust wild-type strains are of perennial concerns for their industrial applications. To overcome...
Citations
... Nevertheless, these techniques are heavily time-consuming and hamper the reduction of the number of colonies to test. High-throughput technologies, such as fluorescence-activated cell sorting (FACS), are promising tools to address this lack of efficiency but still require further innovation and study to take full advantage of it [17,22,25,27]. Exposure to stressful conditions is also a commonly used approach to select mutants with tolerant phenotypes [21]. ...
... There is an increasing need to find efficient alternatives for energy extraction to keep up with the pace of this robust development. In the present era, third-generation biofuels extracted from microalgae are considered as one of the most practical approaches for meeting energy needs [5]. These thirdgeneration biofuels possess the capability of overcoming the challenges faced by the first & secondgeneration biofuels. ...
... Experimentally, it was found that 400 flux is ascertained as the most optimal intensity supporting the growth of the microalgae Chlorella vulgaris. The control variables for this experiment are Scenedesmus obliquus, Chlorophyta sp., Desmodesmus denticulatus, and, Monoraphidium sp. as these recorded the 5 highest values of absorbance [17]. The data extracted also proved that the light and dark periods alternation is essential for photosynthesis as the formation of high-energy substrate nicotinamide adenine dinucleotide phosphate (NADPH) & adenosine-5'-triphosphate (ATP) requires light to stimulate the dark reaction to synthesize carbon skeletons. ...
Chlorella vulgaris has considerable promise as a raw material for biofuel production since it has a high productivity per unit area, has a minimum influence on the environment, and does not significantly affect food security. Nevertheless, the low fatty content of their biomass poses a considerable economic obstacle for commercialization. Increasing the amount of biomass and lipids produced by these algae is essential for improving the economic feasibility of using them as biofuel sources. This review highlights the significance of identifying appropriate algal strains, namely those found in local environments, and utilising mutagenesis and genetic engineering techniques to create 'platform strains'. Prior endeavours have primarily concentrated on altering environmental and dietary parameters to enhance the production of biomass and lipids. Here, we review a scientific literature that examines biotechnological approaches and develops methodologies designed to increase lipid production, emphasising the importance of aligning engineering efforts with breakthroughs in DNA manipulation tools. In addition, the review research evaluates the present economic and commercial situation of algal biorefineries, including any related disadvantages. In summary, this thorough research highlights the importance of using creative methods to tackle the intricacies of lipogenesis and enhance the economic viability of producing biofuels from algae.
... Advancements in synthetic biology have facilitated the design of in silico genetic constructs for efficient transgene expression in microalgae. Strategies, such as codon optimization, promoter selection, and signal peptide fusion, have been used to enhance antigen accumulation and secretion [152] ; (3) provided usefulness in certain situations [27] ; (4) Using methods for detecting transgenes and antigens for quality control and vaccine characterization. Molecular biology techniques, such as quantitative PCR and immunoblotting, enable sensitive and specific detection of transgene expression levels. ...
Microalgal emergence is a promising platform with two‐decade historical background for producing vaccines and biopharmaceuticals. During that period, microalgal‐based vaccines have reported successful production for various diseases. Thus, species selection is important for genetic transformation and delivery methods that have been developed. Although many vaccine prototypes have been produced for infectious and non‐infectious diseases, fewer studies have reached immunological and immunoprotective evaluations. Microalgae‐made vaccines for Staphylococcus aureus , malaria, influenza, human papilloma, and Zika viruses have been explored in their capacity to induce humoral or cellular immune responses and protective efficacies against experimental challenges. Therefore, specific pathogen antigens and immune system role are important and addressed in controlling these infections. Regarding non‐communicable diseases, these vaccines have been investigated for breast cancer; microalgal‐produced therapeutic molecules and microalgal‐made interferon‐α have been explored for hypertension and potential applications in treating viral infections and cancer, respectively. Thus, conducting immunological trials is emphasized, discussing the promising results observed in terms of immunogenicity, desired immune response for controlling affections, and challenges for achieving the desired protection levels. The potential advantages and hurdles associated with this innovative approach are highlighted, underlining the relevance of assessing immune responses in preclinical and clinical trials to validate the efficacy of these biopharmaceuticals. The promising future of this healthcare technology is also envisaged.
... One of the ways to decrease the cost of microalgal biofuel generation is to enhance microalgal biomass concentration during cultivation. Various microalgae species can be positively affected by genetic engineering, chemical modulation, and nanomaterial approach to enhance their biomass growth and metabolite syntheses (Kumar et al., 2020). Advances in algomics techniques (such as lipidomics, genomics, metabolomics, proteomics, and transcriptomics) have granted valuable insights into the microbial responses of microalgal cells toward nutrient uptake, nutrient consumption, metabolite synthesis, metabolite accumulation under stress, as well as competition with surrounding microorganisms (as shown in Figure 1). ...
Microalgal biofuel is a promising solution to replace fossil fuel as a renewable and environmental‐friendly energy source, thereby contributing to the United Nations (UN) Sustainable Development Goals (SDGs), in particular SDG‐7, or Affordable and Clean Energy. Unlike energy crops (like oil palm and sugar cane), microalgae benefit from faster growth rate, higher lipid content, smaller land area required, ability to flourish using waste or brackish water, and posing zero competition with food crops. Microalgae‐derived biofuels (like biodiesel, bioethanol, biomethane, and biohydrogen) are sustainable energy sources that can be produced using well‐developed techniques (e.g., transesterification, fermentation, anaerobic digestion, and Fisher–Tropsch process). To prevent dire climate conditions resulting from the global temperature rise of 1.5°C and resolve worldwide energy security issue, our generation will need to establish and implement renewables on a global scale. To improve the industrial production of microalgal biofuel, the efficiencies of biomass and metabolite production to post‐cultivation biofuel synthesis processes must be enhanced. For the cultivation step, there exist three key techniques that can directly change the traits, structure, and behavior of microalgal cells, and induce them to accumulate targeted metabolites rapidly and in large amounts. These techniques are genetic engineering, chemical modulation, and nanomaterial approach. Genetic engineering commonly alters the chloroplast DNA of microalgae to overexpress or down‐regulate key genes in various metabolic pathways so that the cells accumulate more lipids. Chemicals can also be used to modulate microalgal growth and lipid accumulation by inducing oxidative stress or prevent conversion of lipid molecules. Nanomaterials and nanoparticles can also enhance microalgal lipid production by microenvironmental stress induction, vitamin supplementation, and light backscattering. Therefore, in this review, the recent progress as well as the pros and cons of genetic engineering, chemical modulation, and nanomaterial approach in achieving greater biofuel production from microalgae are comprehensively examined.
... In recent years, the so-called "omics" technologies have been shown to be valuable tools in microalgal research [15][16][17][18]. Omics, which includes genomics, transcriptomics, proteomics and metabolomics, broadly refers to the comprehensive analyses of classes of biological molecules, i.e., DNA, RNA, proteins and metabolites, and their interactions (interactomics, Figure 1). ...
... This approach is becoming central to biomarker discovery from proteomics data, and is beginning to outperform existing assays [27]. Furthermore, AI algorithms have been instrumental in analyzing large-scale proteomic datasets [27][28][29][30], ultimately enabling the identification of novel protein interactions and pathways that are critical for microalgal adaptation to environmental stresses [16,31]. It is noteworthy that the potential of microalgal biotechnology and that of proteomics technologies, along with their respective advantages and disadvantages, have been reviewed elsewhere [11,16,19,21,32,33]. ...
... Furthermore, AI algorithms have been instrumental in analyzing large-scale proteomic datasets [27][28][29][30], ultimately enabling the identification of novel protein interactions and pathways that are critical for microalgal adaptation to environmental stresses [16,31]. It is noteworthy that the potential of microalgal biotechnology and that of proteomics technologies, along with their respective advantages and disadvantages, have been reviewed elsewhere [11,16,19,21,32,33]. Therefore, these topics are not the primary focus of this review. ...
Microscopic, photosynthetic prokaryotes and eukaryotes, collectively referred to as microalgae, are widely studied to improve our understanding of key metabolic pathways (e.g., photosynthesis) and for the development of biotechnological applications. Omics technologies, which are now common tools in biological research, have been shown to be critical in microalgal research. In the past decade, significant technological advancements have allowed omics technologies to become more affordable and efficient, with huge datasets being generated. In particular, where studies focused on a single or few proteins decades ago, it is now possible to study the whole proteome of a microalgae. The development of mass spectrometry-based methods has provided this leap forward with the high-throughput identification and quantification of proteins. This review specifically provides an overview of the use of proteomics in fundamental (e.g., photosynthesis) and applied (e.g., lipid production for biofuel) microalgal research, and presents future research directions in this field.
... Phaeodactylum tricornutum is a marine unicellular diatom that is considered a source of PUFA, EPA, chlorophylls, phenolic compounds, and carotenoids such as fucoxanthin, a pigment of marine origin that shows anti-inflammatory, antioxidant and anticarcinogenic effects (Fajardo et al., 2007;Neumann et al., 2019). However, both growth and nutritional composition depend not only on the selected microalgae species but also on factors such as temperature, salinity, nutrient availability, and pH (Kumar et al., 2020). For this reason, it is of interest to study the microalgae P. tricornutum as a source of bioactive compounds that can be used in dietary supplements to reduce the increasing prevalence of concomitant diseases such as inflammation and oxidative stress, which in turn contribute to the development of cancer (Fajardo et al., 2007). ...
... Microalgae, renowned for their ability to efficiently convert solar energy and CO 2 into biomass, are recognized as a promising and sustainable source of energy and a diverse array of high-value products. They have demonstrated utility across multiple sectors, including energy, pharmaceuticals, industrial chemicals, and nutraceuticals [1,2]. In particular, due to the continuous increase in atmospheric CO 2 levels caused by human activities, it is imperative to explore and develop strategies for enhancing the carbon fixation potential of microalgae [3]. ...
Rubisco large-subunit methyltransferase (LSMT), a SET-domain protein lysine methyltransferase, catalyzes the formation of trimethyl-lysine in the large subunit of Rubisco or in fructose-1,6-bisphosphate aldolases (FBAs). Rubisco and FBAs are both vital proteins involved in CO2 fixation in chloroplasts; however, the physiological effect of their trimethylation remains unknown. In Nannochloropsis oceanica, a homolog of LSMT (NoLSMT) is found. Phylogenetic analysis indicates that NoLSMT and other algae LSMTs are clustered in a basal position, suggesting that algal species are the origin of LSMT. As NoLSMT lacks the His-Ala/ProTrp triad, it is predicted to have FBAs as its substrate instead of Rubisco. The 18–20% reduced abundance of FBA methylation in NoLSMT-defective mutants further confirms this observation. Moreover, this gene (nolsmt) can be induced by low-CO2 conditions. Intriguingly, NoLSMT-knockout N. oceanica mutants exhibit a 9.7–13.8% increase in dry weight and enhanced growth, which is attributed to the alleviation of photoinhibition under high-light stress. This suggests that the elimination of FBA trimethylation facilitates carbon fixation under high-light stress conditions. These findings have implications in engineering carbon fixation to improve microalgae biomass production.
... In parallel with selecting the most appropriate DNA elements required for transformation, various techniques have been developed to facilitate the uptake of foreign DNA into the cell and subsequently into the nucleus, chloroplast, or mitochondria of the algae, for ensuring higher yields of the targeted metabolite (lipids, antioxidants, high-value bioactive compounds, and proteins). Nevertheless, in contrast to the plant systems, the transformation of microalgae continues to face challenges in achieving high efficiency, with the exception of Chlamydomonas (Kumar et al., 2020). ...
... Assuming a conservative photosynthetic efficiency and the need to counteract Table 3 Comparative analysis of algae with other organisms and terraforming methods. atmospheric escape, the path to a minimally breathable atmosphere hinges on bioengineering advances and the development of supportive technologies for large-scale cultivation and environmental management (Kumar et al., 2020;Long et al., 2022). Creating contained biomes where multiple organisms coexist, each playing a specific role (e.g., algae producing oxygen, fungi breaking down rocks, and mosses stabilizing the soil), could serve as prototypes for more expansive Martian ecosystems (Silverstone et al., 2003). ...
The Martian environment, characterized by extreme aridity, frigid temperatures, and a lack of atmospheric oxygen , presents a formidable challenge for potential terraforming endeavors. This review article synthesizes current research on utilizing algae as biocatalysts in the proposed terraforming of Mars, assessing their capacity to facilitate Martian atmospheric conditions through photosynthetic bioengineering. We analyze the physiological and genetic traits of extremophile algae that equip them for survival in extreme habitats on Earth, which serve as analogs for Martian surface conditions. The potential for these organisms to mediate atmospheric change on Mars is evaluated, specifically their role in biogenic oxygen production and carbon dioxide sequestration. We discuss strategies for enhancing algal strains' resilience and metabolic efficiency, including genetic modification and the development of bioreactors for controlled growth in extraterrestrial environments. The integration of algal systems with existing mechanical and chemical terraforming proposals is also examined, proposing a synergistic approach for establishing a nascent Martian biosphere. Ethical and ecological considerations concerning introducing terrestrial life to extra-planetary bodies are critically appraised. This appraisal includes an examination of potential ecological feedback loops and inherent risks associated with biological terraforming. Biological ter-raforming is the theoretical process of deliberately altering a planet's atmosphere, temperature, and ecosystem to render it suitable for Earth-like life. The feasibility of a phased introduction of life, starting with microbial taxa and progressing to multicellular organisms, fosters a supportive atmosphere on Mars. By extending the frontier of biotechnological innovation into space, this work contributes to the foundational understanding necessary for one of humanity's most audacious goals-the terraforming of another planet.
... Microalgae have emerged as a promising group of organisms for pursuing sustainable solutions, specifically in bioproducts, biofuels, and consumer nutritional supplements. The recent data availability and advances in high-throughput techniques helped better understand and characterize the biology of microalgae (Kumar et al., 2020;Villanova and Spetea, 2021;Helmy et al., 2023). ...
Microalgae are emerging as a sustainable source of bioproducts, including food, animal feed, nutraceuticals, and biofuels. This review emphasizes the need to carefully select suitable species and highlights the importance of strain optimization to enhance the feasibility of developing algae as a sustainable resource for food and biomaterial production. It discusses microalgal bioprospecting methods, different types of cultivation systems, microalgal biomass yields, and cultivation using wastewater. The paper highlights advances in artificial intelligence that can optimize algal productivity and overcome the limitations faced in current microalgal industries. Additionally, the potential of UV mutagenesis combined with high-throughput screening is examined as a strategy for generating improved strains without introducing foreign genetic material. The necessity of a multifaceted optimization approach for enhanced productivity is acknowledged. This review provides an overview of recent developments crucial for the commercial success of microalgal production.
