Novel Insights into Phosphorus Deprivation Boosted Lipid Synthesis in the Marine Alga Nannochloropsis oceanica without Compromising Biomass Production

作者：Ying Shi, Meijing Liu, Wei Ding, Jin Liu · 发表于：Journal of Agricultural and Food Chemistry · 年份：2020 · DOI：10.1021/acs.jafc.0c04899 · 被引用次数：53 · 研究领域：Algal biology and biofuel production、Microbial Metabolic Engineering and Bioproduction、Photosynthetic Processes and Mechanisms

Nannochloropsis oceanica represents a preferred oleaginous alga for producing lipids. Here we found that phosphorus deprivation (PD) caused a severe decrease in protein and a considerable increase in lipids including triacylglycerol (TAG), yet it had little effect on the carbohydrate level and biomass production of N. oceanica . The combinatorial analysis by integrating physiological, biochemical, and transcriptomic data unraveled the molecular mechanisms underlying PD-induced lipid accumulation. Albeit attenuating the Calvin–Benson cycle, PD stimulated the C4-like pathway to maintain CO 2 fixation for biomass production. PD attenuated nitrogen utilization and enhanced protein catabolism thus leading to protein decrease, from which the carbon was likely salvaged into the stimulated tricarboxylic acid cycle for supplying lipid synthesis with carbon precursors. The impairment of TAG catabolism by downregulating certain lipases rather than the stimulation of TAG assembly pathways contributed to PD-boosted TAG increase. These findings provide novel insights into PD-induced lipogenesis without compromising biomass production by N. oceanica .