Division of Biotechnology and Life Science, Institute of Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Naka-cho, Koganei, Tokyo, 184-8588, Japan.
Biotechnology Laboratory, Electric Power Development CO., Ltd., 1, Yanagisaki-machi, Wakamatsu-ku, Kitakyushu, Fukuoka, 808-0111, Japan.
Sci Rep. 2021 Oct 22;11(1):20905. doi: 10.1038/s41598-021-00453-w.
Microalgae are promising producers of biofuel due to higher accumulation of triacylglycerol (TAG). However, further improvement of the lipid metabolism is critical for feasible application of microalgae in industrial production of biofuel. Suppression of lipid degradation pathways is a promising way to remarkably increase the lipid production in model diatoms. In this study, we established an antisense-based knockdown (KD) technique in the marine oleaginous diatom, Fistulifera solaris. This species has a capability to accumulate high content of lipids. Tgl1 KD showed positive impact on cell growth and lipid accumulation in conventional culture in f/2 medium, resulting in higher oil contents compared to wild type strain. However, these impacts of Tgl1 KD were slight when the cells were subjected to the two-stage growth system. The Tgl1 KD resulted in slight change of fatty acid composition; increasing in C14:0, C16:0 and C16:1, and decreasing in C20:5. This study indicates that, although Tgl1 played a certain role in lipid degradation in F. solaris, suppression of only a single type of TAG lipase was not significantly effective to improve the lipid production. Comprehensive understanding of the lipid catabolism in this microalga is essential to further improve the lipid production.
微藻由于能够积累大量的三酰基甘油(TAG)，因此是有前途的生物燃料生产者。然而，进一步改善脂代谢对于微藻在生物燃料工业生产中的可行应用至关重要。抑制脂降解途径是显著增加模型硅藻中脂产量的一种有前途的方法。在本研究中，我们在海洋产油硅藻 Fistulifera solaris 中建立了基于反义的敲低 (KD) 技术。该物种具有积累高含量脂质的能力。与野生型菌株相比，Tgl1 KD 在 f/2 培养基的常规培养中对细胞生长和脂质积累有积极影响，导致油含量更高。然而，当细胞处于两阶段生长系统时，Tgl1 KD 的这些影响很小。Tgl1 KD 导致脂肪酸组成略有变化；C14:0、C16:0 和 C16:1 增加，C20:5 减少。本研究表明，尽管 Tgl1 在 F. solaris 的脂降解中发挥了一定作用，但仅抑制一种 TAG 脂肪酶对提高脂产量的效果并不显著。全面了解该微藻的脂分解代谢对于进一步提高脂产量至关重要。
