Using transcriptomic analysis, the group of XU Jian at CAS Qingdao Institute of Bioenergy and Bioprocess Technology (QIBEBT) observed a nuclear-encoded RuBisCO activase (nRCA) in Nannochlorpsis oceanica which functions as a mechanochemical motor protein and uses the energy from ATP hydrolysis to facilitate carbamylation and thus maintaining activity of RuBisCO by removing various inhibitors from RuBisCO catalytic sites. By overexpressing RCA, microalgal growth rate under air-level CO2 was enhanced by ~32%, biomass accumulation by ~46% and lipid productivity by ~41%, and photosynthesis by ~28%. Furthermore, abundance of RuBisCO large subunit protein increased by ~45%.
CAS news release, September 4, 2017