College of Pharmacy, Zhejiang University of Technology, Hangzhou, 310014, China.
College of Biological, Chemical Science and Engineering, Jiaxing University, Jiaxing, 314001, People's Republic of China.
World J Microbiol Biotechnol. 2022 Jul 14;38(9):160. doi: 10.1007/s11274-022-03346-w.
Photosynthetic and metabolomic performance of Euglena gracilis was examined and compared under autotrophic and mixotrophic conditions. Autotrophic protozoa (AP) obtained greater biomass (about 33% higher) than the mixotrophic protozoa (MP) after 12 days of growth. AP maintained steady photosynthesis, while MP showed a remarkable decrease in photosynthetic efficiency and dropped to an extremely low level at day 12. In MP, low light absorption and photosynthetic electron transport efficiency, and high energy dissipation were reflected by the chlorophyll (chl a) fluorescence (OJIP) of the protozoa. The values of Ψ, Φ, and ET/RC of MP decreased to extremely low levels, to 1/15, 1/46, and 1/9 those of AP, respectively, while DI/RC increased to approximately 16 times that of AP. A total of 137 metabolites were showed significant differences between AP and MP. AP accumulated more monosaccharide, lipids, and alkaloids, while MP produced more amino acids, peptides, and long-chain fatty acids including poly-unsaturated fatty acids. The top nine most important enriched pathways obtained from KEGG mapping were related to ABC transporters, biosynthesis of amino acids, purine metabolism, and carbohydrate metabolism. There were significant differences between AP and MP in photosynthetic activity, metabolites, and metabolic pathways. This work presented useful information for the production of high value bioproducts in E. gracilis cultured under different nutritional conditions.
研究并比较了自养和混合营养条件下绿眼虫的光合和代谢表现。在 12 天的生长后，自养原生动物（AP）获得了比混合营养原生动物（MP）更高的生物量（约高 33%）。AP 保持稳定的光合作用，而 MP 的光合作用效率显著下降，并在第 12 天降至极低水平。在 MP 中，低光吸收和光合电子传递效率，以及高能量耗散反映在原生动物的叶绿素（chl a）荧光（OJIP）上。MP 的Ψ、Φ和 ET/RC 值分别降低到 AP 的 1/15、1/46 和 1/9 的极低水平，而 DI/RC 增加到 AP 的约 16 倍。AP 和 MP 之间共有 137 种代谢物存在显著差异。AP 积累了更多的单糖、脂质和生物碱，而 MP 产生了更多的氨基酸、肽和长链脂肪酸，包括多不饱和脂肪酸。KEGG 映射获得的前 9 个最重要的富集途径与 ABC 转运蛋白、氨基酸生物合成、嘌呤代谢和碳水化合物代谢有关。AP 和 MP 在光合活性、代谢物和代谢途径方面存在显著差异。这项工作为在不同营养条件下培养的绿眼虫生产高价值生物制品提供了有用的信息。
