Crypthecodinium cohnii strain:ATCC 30556 Raw sequence reads. Crypthecodinium cohnii strain:ATCC 30556

Docosahexaenoic acid (DHA) has been demonstrated with valuable medical and nutritional applications. The heterotrophic microalga Crypthecodinium cohnii is well known for its lipid accumulation with a high fraction of DHA. In this study, we developed a novel screening approach for high growth and lipid-content mutants of C. cohnii using acetyl-CoA carboxylase (ACCase) inhibitor sethoxydim. C. cohnii mutants were generated using atmospheric and room temperature plasma (ARTP) and then screened for two rounds in media supplemented with sethoxydim. The efforts led to identification of a mutant M-1-2 with 24.32% higher growth and 7.45% higher lipid content than those of the wild type, respectively, demonstrating the effectiveness of the sethoxydim-based screening. Consistently, a comparative transcriptomic analysis showed that the ACCase encoding genes were up-regulated by 1.53 to 3.12 folds in the M-1-2 mutant. In addition, transcripts involved in fatty acid biosynthesis, energy, central carbohydrate, and amino acid metabolism were also up-regulated in the mutant when compared with the wild type.