School of Food and Biological Engineering, Shaanxi University of Science and Technology, Xi'an 710021, China; School of Ecology and Environment, Northwestern Polytechnical University, Xi'an 710012, China.
School of Food and Biological Engineering, Shaanxi University of Science and Technology, Xi'an 710021, China.
J Colloid Interface Sci. 2023 Nov;649:22-35. doi: 10.1016/j.jcis.2023.06.049. Epub 2023 Jun 13.
Carbon dots (CDs) have attracted increasing attention for their ability to artificially improve photosynthesis. Microalgal bioproducts have emerged as promising sources of sustainable nutrition and energy. However, the gene regulation mechanism of CDs on microalgae remains unexplored. The study synthesized red-emitting CDs and applied them to Chlamydomonas reinhardtii. Results showed that 0.5 mg/L-CDs acted as light supplements to promote cell division and biomass in C. reinhardtii. CDs improved the energy transfer of PS II, photochemical efficiency of PS II, and photosynthetic electron transfer. The pigment content and carbohydrate production slightly increased, while protein and lipid contents significantly increased (by 28.4% and 27.7%, respectively) in a short cultivation time. Transcriptome analysis identified 1166 differentially expressed genes. CDs resulted in faster cell growth by up-regulating the expression of genes associated with cell growth and death, promoting sister chromatid separation, accelerating the mitotic process and shortening the cell cycle. CDs improved the ability of energy conversion by up-regulating photosynthetic electron transfer-related genes. Carbohydrate metabolism-related genes were regulated and provided more available pyruvate for the citrate cycle. The study provides evidence for the genetic regulation of microalgal bioresources by artificially synthesized CDs.
碳点（CDs）因其能够人为地提高光合作用而受到越来越多的关注。微藻生物产品作为可持续营养和能源的有前途的来源已经出现。然而，CDs 对微藻的基因调控机制仍未被探索。本研究合成了红色发射 CDs，并将其应用于莱茵衣藻。结果表明，0.5mg/L-CDs 作为光补充剂，促进了莱茵衣藻的细胞分裂和生物量增加。CDs 提高了 PS II 的能量转移、PS II 的光化学效率和光合作用电子传递。在短时间培养过程中，色素含量和碳水化合物产量略有增加，而蛋白质和脂质含量显著增加（分别增加了 28.4%和 27.7%）。转录组分析鉴定出 1166 个差异表达基因。CDs 通过上调与细胞生长和死亡相关的基因表达，促进姐妹染色单体分离，加速有丝分裂过程并缩短细胞周期，从而实现更快的细胞生长。CDs 通过上调与光合作用电子传递相关的基因来提高能量转换能力。调节碳水化合物代谢相关基因，并为柠檬酸循环提供更多可用的丙酮酸。该研究为人工合成 CDs 对微藻生物资源的遗传调控提供了证据。
