Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences , Wuhan 430062 , P. R. China.
Key Laboratory of Biology and Genetic Improvement of Oil Crops , Ministry of Agriculture , Wuhan 430062 , P. R. China.
J Agric Food Chem. 2019 Aug 28;67(34):9683-9693. doi: 10.1021/acs.jafc.9b03536. Epub 2019 Aug 19.
sp. A-2 is a heterotrophic marine fungus used for the commercial production of docosahexaenoic acid (DHA). However, the pattern of the distribution of DHA and how DHA is channeled into phospholipid (PL) and triacylglycerol (TAG) are unknown. In this study, we systematically analyzed the distribution of DHA in TAG and PL during the growth of the cell. The migration of DHA from PL to TAG was presumed during the fermentation cycle. DHA and docosapentaenoic acid were accumulated in both TAG and phosphatidylcholine (PC), whereas eicosapentaenoic acid was mainly deposited in PC. RNA seq revealed that malic enzyme may provide lipogenic NADPH. In addition, long-chain acyl-CoA synthase and acyl-CoA:lysophosphatidylcholine acyltransferase may participate in the accumulation of DHA in PL. No phosphatidylcholine:diacylglycerol cholinephosphotransferase was identified from the genome sequence. In contrast, phospholipid:diacylglycerol acyltransferase-mediated acyl-CoA-independent TAG synthesis pathway and phospholipase C may contribute to the channeling of DHA from PC to TAG.
A-2 株是一种用于商业化生产二十二碳六烯酸（DHA）的异养海洋真菌。然而，DHA 的分布模式以及 DHA 如何被转入磷脂（PL）和三酰基甘油（TAG）中尚不清楚。在本研究中，我们系统地分析了细胞生长过程中 TAG 和 PL 中 DHA 的分布情况。在发酵周期中推测 DHA 从 PL 向 TAG 的转移。DHA 和二十二碳五烯酸（docosapentaenoic acid）均在 TAG 和磷脂酰胆碱（phosphatidylcholine，PC）中积累，而二十碳五烯酸（eicosapentaenoic acid）主要沉积在 PC 中。RNA seq 表明，苹果酸酶可能为脂生物合成提供 NADPH。此外，长链酰基辅酶 A 合成酶和酰基辅酶 A：溶血磷脂酰胆碱酰基转移酶可能参与了 PL 中 DHA 的积累。从基因组序列中未鉴定出磷脂酰胆碱：二酰基甘油胆碱磷酸转移酶。相反，磷脂：二酰基甘油酰基转移酶介导的酰基辅酶 A 非依赖性 TAG 合成途径和磷脂酶 C 可能有助于 DHA 从 PC 向 TAG 的转移。
