Improving the sunlight-to-biomass conversion efficiency in microalgal biofactories

Area of Science:

• Biotechnology
• Sustainable Energy
• Algal Research

Background:

• Microalgae are vital for sustainable production of chemicals and fuels.
• Current microalgal mass culture productivity is limited by inefficient sunlight-to-biomass conversion.
• Energy losses occur during carbon dioxide conversion, with light-harvesting systems being a major factor.

Purpose of the Study:

• To explore strategies for enhancing microalgal culture productivity.
• To identify key targets for strain engineering to improve sunlight conversion efficiency.
• To assess methods for generating improved microalgal strains.

Main Methods:

• Reviewing engineering approaches for light-harvesting systems.
• Investigating metabolic engineering of the Calvin-Benson cycle and photorespiratory bypasses.
• Considering random mutagenesis and high-throughput screening for strain development.

Main Results:

• Truncating light-harvesting antennas in Chlamydomonas reinhardtii increases productivity under saturating light.
• Engineering the Calvin-Benson cycle and photorespiratory bypasses in A. thaliana enhances biomass productivity.
• These approaches demonstrate potential for improving microalgal efficiency.

Conclusions:

• Strain engineering, particularly targeting light-harvesting and metabolic pathways, is crucial for economic microalgae-based production.
• An expanded molecular toolkit is needed for efficient, targeted engineering of microalgae.
• Random mutagenesis and screening offer a viable alternative for generating improved strains in the interim.