Methods for Mutagenesis in Microalga Biotechnology

Richard Bessils^*
*Correspondence: Richard Bessils, Department of Biotechnology, Technical University Dresden, Dresden, Germany, Email:

Introduction

Microalgae have emerged as a promising source of biofuels, pharmaceuticals, and valuable compounds due to their high growth rates, efficient nutrient utilization, and ability to photosynthetically convert carbon dioxide into biomass. To further harness the potential of microalgae for biotechnological applications, genetic engineering and mutagenesis techniques are crucial tools. Mutagenesis, the induction of genetic changes, enables the modification of microalgal genomes to enhance desired traits. This article provides an overview of various methods employed in microalgal mutagenesis, including chemical mutagenesis, radiation mutagenesis, and targeted mutagenesis techniques such as CRISPR-Cas9.

Chemical mutagenesis involves the use of chemical agents that induce genetic alterations in microalgae. Ethyl methanesulfonate and N-methyl-N'- nitro-N-nitrosoguanidine are commonly used chemical mutagens. These agents chemically modify DNA, resulting in base substitutions, deletions, or insertions. Chemical mutagenesis can be applied to large populations of microalgae, allowing for the screening of mutants with desired traits. However, it is a random process, and the identification of desired mutants can be time-consuming. Radiation mutagenesis involves the use of ionizing radiation, such as X-rays or gamma rays, to induce genetic mutations in microalgae. Ionizing radiation generates free radicals that cause DNA damage, leading to mutations. The advantage of radiation mutagenesis is that it induces a wide range of genetic changes, including point mutations, deletions, and chromosomal rearrangements [1]. However, it is a relatively non-specific process, making it challenging to control the types of mutations generated. Furthermore, radiation mutagenesis requires specialized equipment and facilities, limiting its accessibility.

Description

With recent advancements in molecular biology, targeted mutagenesis techniques have revolutionized genetic manipulation in microalgae. One such technique is the CRISPR-Cas9 system, which enables precise genome editing. The CRISPR-Cas9 system consists of a guide RNA that guides the Cas9 nuclease to a specific DNA sequence, where it introduces double-strand breaks. These breaks can then be repaired by the cell's natural repair mechanisms, leading to targeted gene modifications.To apply CRISPR-Cas9 in microalgae, the first step is to design the gRNA to match the target gene. The gRNA is then synthesized and delivered into microalgal cells along with the Cas9 nuclease using various delivery methods, such as electroporation or biolistic transformation. After successful delivery, the CRISPR-Cas9 system induces DSBs at the target site, and the repair process can be directed towards desired outcomes, such as gene knockout or precise gene insertion [2].

Although CRISPR-Cas9 has revolutionized targeted mutagenesis, its application in microalgae still faces challenges. Efficient delivery of the CRISPRCas9 components into microalgal cells is one major hurdle. Additionally, the repair mechanisms in microalgae may differ from those in other organisms, affecting the efficiency of the desired modifications [3].

Mutagenesis techniques have significantly advanced microalgal biotechnology by enabling the targeted modification of microalgal genomes. Chemical mutagenesis and radiation mutagenesis offer random mutagenesis approaches, allowing the screening of large populations for desired traits. However, these methods lack precision and control over the types of mutations induced. In contrast, targeted mutagenesis techniques, such as the CRISPRCas9 system, provide precise genome editing capabilities. CRISPR-Cas9 has revolutionized genetic manipulation in microalgae, allowing for the knockout of specific genes or the insertion of desired genetic sequences. However, challenges remain, particularly in efficient delivery and understanding repair mechanisms in microalgae [4,5].

Conclusion

Future research in microalgal mutagenesis should focus on optimizing delivery methods, increasing the efficiency of desired modifications, and expanding the understanding of repair mechanisms in microalgae. By enhancing these techniques, microalgal biotechnology can unlock even greater potential in areas such as biofuel production, pharmaceutical synthesis, and environmental remediation.

Acknowledgement

None.

Conflict of Interest

There is no conflict of interest by author.

References

1. Chen, Chun-Yen, Chienyan Hsieh, Duu-Jong Lee and Chien-Hsiang Chang, et al. "Production, extraction and stabilization of lutein from microalga chlorella sorokiniana MB-1." Bioresour Technol 200 (2016): 500-505.

Google Scholar, Crossref, Indexed at

2. De Jesus Raposo, Maria Filomena, Alcina Maria Bernardo De Morais and Rui Manuel Santos Costa De Morais. "Marine polysaccharides from algae with potential biomedical applications." Mar Drugs 13 (2015): 2967-3028.

Google Scholar, Crossref, Indexed at

3. Brányiková, Irena, Barbora Maršálková, Jiří Doucha and Tomáš Brányik, et al. "Microalgae-novel highly efficient starch producers." Biotechnol Bioeng 108 (2011): 766-776.

Google Scholar, Crossref, Indexed at

4. Loh, Saw Hong, Mee Kee Chen, Nur Syazana Fauzi and Ahmad Aziz, et al. "Enhanced fatty acid methyl esters recovery through a simple and rapid direct transesterification of freshly harvested biomass of C. vulgaris and M. gracile." Sci Rep 11 (2021): 2720.

Google Scholar, Crossref, Indexed at

5. Woolston, Benjamin M., Steven Edgar and Gregory Stephanopoulos. "Metabolic engineering: Past and future." Annu Rev Chem Biomol 4 (2013): 259-288.

Google Scholar, Crossref, Indexed at