Ge Chengfeng, Chen Haiqin, Mei Tiantian, Tang Xin, Chang Lulu, Gu Zhennan, Zhang Hao, Chen Wei, Chen Yong Q
State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, China.
School of Food Science and Technology, Jiangnan University, Wuxi, China.
Front Bioeng Biotechnol. 2018 Jan 22;5:89. doi: 10.3389/fbioe.2017.00089. eCollection 2017.
In the industrial oleaginous fungus a, the arachidonic acid (AA; C20:4; ω-6) fraction can reach 50% of the total fatty acids (TFAs) . However, the eicosapentaenoic acid (EPA; C20:5; ω-3) fraction is less than 3% when this fungus is cultivated at a low temperature (12°C). Omega-3 fatty acid desaturase is a key enzyme in ω-3 long-chain polyunsaturated fatty acids biosynthesis pathways. To enhance EPA production, we transformed the ω-3 fatty acid desaturase (PaD17), which exhibits strong Δ-17 desaturase activity, into , thus increasing the AA to EPA conversion rate to 49.8%. This PaD17-harboring reconstruction strain produced 617 mg L of EPA at room temperature in broth medium, this yield was increased to 1.73 g L after culture medium optimization (i.e., about threefold higher than that under original culture conditions), with concomitant respective increases in dry cell weight and TFA content to 16.55 and 6.46 g L. These findings suggest a new platform for the future industrial production of EPA.
在工业产油真菌a中，花生四烯酸（AA；C20:4；ω-6）部分可占总脂肪酸（TFA）的50%。然而，当这种真菌在低温（12°C）下培养时，二十碳五烯酸（EPA；C20:5；ω-3）部分低于3%。ω-3脂肪酸去饱和酶是ω-3长链多不饱和脂肪酸生物合成途径中的关键酶。为了提高EPA产量，我们将具有强Δ-17去饱和酶活性的ω-3脂肪酸去饱和酶（PaD17）导入……，从而使AA到EPA的转化率提高到49.8%。这种携带PaD17的重组菌株在肉汤培养基中室温下产生617毫克/升的EPA，经过培养基优化后，该产量提高到1.73克/升（即比原始培养条件下高约三倍），同时干细胞重量和TFA含量分别增加到16.55克/升和6.46克/升。这些发现为未来EPA的工业化生产提供了一个新平台。
