In a study published in Bioresource Technology, researchers from the Institute of Modern Physics (IMP) of the Chinese Academy of Sciences and their collaborators, revealed that heavy-ion beams mutagenesis could affect energy and carbon metabolism in microalgae mutants, providing a new approach for developing engineering microalgae strains with enhanced carbon fixation abilities. Microalgae possess a strong ability to convert solar energy and carbon dioxide into biomass and high-value bioproducts, and have broad applications in carbon capture, utilization, and storage, as well as waste treatment.
However, the biotechnological applications of microalgae have been limited due to the lack of comprehensive understanding of their carbon metabolism and energy conversion. Aimed at coordinating energy utilization and carbon allocation, strain improvement is emerging as a promising strategy.
Using the Heavy Ion Research Facility in Lanzhou (HIRFL), the researchers applied the effective strain improvement technique, heavy-ion beams mutagenesis, to the environmentally adaptable microalgae Scenedesmus quadricauda.
After several rounds of screening, they identified two distinct mutants. One mutant showed low photosynthetic activity and biomass productivity, while the other mutant demonstrated adaptability to prolonged high light stress and achieved a 28.34 % increase in biomass yield compared with the wild-type strain.
Integrating their photosynthetic characteristics with comparative proteomics analysis, the researchers discovered that the contrasting protein regulations from central carbon metabolism mainly affect the different biomass accumulation patterns of the two mutants.
Furthermore, they found that divergent regulation of the tricarboxylic acid cycle following heavy-ion beams mutagenesis could be potential targets for developing engineering microalgal strains with superior biomass and high-value products.
This study shows that heavy-ion beams mutagenesis is a powerful breeding technique, which has significant advantages in producing robust microalgal mutant strains with potential for industrial applications.
