Study on high-CO2 tolerant Dunaliella salina and its mechanism via transcriptomic analysis

Bo Huang; Gaopin Qu; Yulong He; Jinli Zhang; Jianhua Fan; Tao Tang

doi:10.3389/fbioe.2022.1086357

Study on high-CO₂ tolerant Dunaliella salina and its mechanism via transcriptomic analysis

Front Bioeng Biotechnol. 2022 Dec 1:10:1086357. doi: 10.3389/fbioe.2022.1086357. eCollection 2022.

Authors

Bo Huang¹, Gaopin Qu², Yulong He², Jinli Zhang¹, Jianhua Fan², Tao Tang¹

Affiliations

¹ CAS Key Lab of Low-Carbon Conversion Science and Engineering, Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai, China.
² State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China.

Abstract

Microalgae has been regarded as a promising method for reducing CO₂ emission. High CO₂ concentration generally inhibits algal growth, and previous studies have mostly focused on breeding freshwater algae with high CO₂ tolerance. In this study, one marine algal strain Dunaliella salina (D. salina) was grown under 0.03%-30 % CO₂ and 3% NaCl conditions, and was evaluated to determine its potential for CO₂ assimilation. The results showed that D. salina could tolerate 30% CO₂ , and its maximum biomass concentration could reach 1.13 g·L^-1 after 8 days incubation, which was 1.85 times higher than that of incubation in air (0.03%). The phenomenon of high-CO₂ tolerance in D. salina culture was discussed basing on transcriptome analysis. The results showed that D. salina was subjected to oxidative stress under 30% CO₂ conditions, and the majority genes involving in antioxidant system, such as SOD, CAT, and APX genes were up-regulated to scavenge ROS. In addition, most of the key enzyme genes related to photosynthesis, carbon fixation and metabolism were up-regulated, which are consistent with the higher physiological and biochemical values for D. salina incubation under 30% CO₂ .

Keywords: D. salina; antioxidant system; high-CO2 tolerance; high-salt tolerance; transcriptomic analysis.