Genetic Engineering of the Calvin Cycle in Microalgae

Photosynthetic microalgae are emerging as potential biomass feedstock for biofuel production. Mitigation of carbon dioxide release through these organisms can be a promising alternative to the existing carbon sequestration methods. However, the relatively low photosynthetic capacity of microalgae has hampered its use in carbon dioxide mitigation.

The team of Bo Yang from Peking University in China improved the photosynthetic capacity of the green microalga Chlorella vulgaris by manipulating its Calvin cycle. The team introduced the cyanobacterial fructose 1,6-bisphosphate aldolase into the C. vulgaris chloroplast, leading to enhanced photosynthetic capacity and cell growth.

Analysis suggested a possible role for aldolase overexpression in promoting the regeneration of ribulose 1,5-bisphosphate in the Calvin cycle and energy transfer in photosystems. This study is a proof-of-concept of enhancing the photosynthetic capacity by engineering the Calvin cycle in green microalgae.