Aurantiochytrium sp., a marine thraustochytrid possesses a remarkable ability to produce lipid rich in polyunsaturated fatty acids (PUFAs), such as docosahexaenoic acid (DHA). Although gene regulation underlying lipid biosynthesis has been previously reported, proteomic analysis is still limited. In this study, high DHA accumulating strain Aurantiochytrium sp. SW1 has been used as a study model to elucidate the alteration in proteome profile under different cultivation phases i.e. growth, nitrogen-limitation and lipid accumulation. Of the total of 5146 identified proteins, 852 proteins were differentially expressed proteins (DEPs). The largest number of DEPs (488 proteins) was found to be uniquely expressed between lipid accumulating phase and growth phase. Interestingly, there were up-regulated proteins involved in glycolysis, glycerolipid, carotenoid and glutathione metabolism which were preferable metabolic routes towards lipid accumulation and DHA production as well as cellular oxidative defence. Integrated proteomic and transcriptomic data were also conducted to comprehend the gene and protein regulation underlying the lipid and DHA biosynthesis. A significant up-regulation of acetyl-CoA synthetase was observed which suggests alternative route of acetate metabolism for acetyl-CoA producer. This study presents the holistic routes underlying lipid accumulation and DHA production in Aurantiochytrium sp. SW1 and other relevant thraustochytrid.

Aurantiochytrium sp. 是一种海洋破囊壶菌，具有产生富含多不饱和脂肪酸 (PUFA)（例如二十二碳六烯酸(DHA)）的脂质的卓越能力。尽管之前已经报道了脂质生物合成的基因调控，但蛋白质组学分析仍然有限。在本研究中，高 DHA 积累菌株Aurantiochytrium sp. SW1 已被用作研究模型来阐明不同培养阶段（即生长、氮限制和脂质积累）下蛋白质组谱的变化。在总共 5146 个已鉴定的蛋白质中，852 个蛋白质是差异表达蛋白质 (DEP)。发现最大数量的 DEP（488 个蛋白质）在脂质积累期和生长期之间独特表达。有趣的是，参与糖酵解、甘油脂、类胡萝卜素和谷胱甘肽代谢的蛋白质上调，这些蛋白质是脂质积累、DHA 产生以及细胞氧化防御的优选代谢途径。还进行了整合的蛋白质组学和转录组学数据，以了解脂质和 DHA 生物合成背后的基因和蛋白质调控。观察到乙酰辅酶A合成酶的显着上调，这表明乙酰辅酶A生产者的乙酸代谢的替代途径。这项研究提出了Aurantiochytrium sp中脂质积累和 DHA 生产的整体途径。SW1 和其他相关的破囊壶菌。