sp. PKU#Mn4 的 ARTP 诱变和基于Clethodim 的突变体筛选以提高二十二碳六烯酸的积累。

ARTP Mutagenesis of sp. PKU#Mn4 and Clethodim-Based Mutant Screening for Enhanced Docosahexaenoic Acid Accumulation.

机构信息

Center for Marine Environmental Ecology, School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China.

Polar Research Institute of China, Shanghai 200136, China.

出版信息

Mar Drugs. 2021 Oct 7;19(10):564. doi: 10.3390/md19100564.

species are one of the best oleaginous thraustochytrids for high-yield production of docosahexaenoic acid (DHA, 22:6). However, the DHA yields from most wild-type (WT) strains of are unsatisfactory for large-scale production. In this study, we applied the atmospheric and room-temperature plasma (ARTP) tool to obtain the mutant library of a previously isolated strain of (i.e., PKU#Mn4). Two rounds of ARTP mutagenesis coupled with the acetyl-CoA carboxylase (ACCase) inhibitor (clethodim)-based screening yielded the mutant A78 that not only displayed better growth, glucose uptake and ACCase activity, but also increased (54.1%) DHA content than that of the WT strain. Subsequent optimization of medium components and supplementation improved the DHA content by 75.5 and 37.2%, respectively, compared with that of mutant A78 cultivated in the unoptimized medium. Interestingly, the ACCase activity of mutant A78 in a medium supplemented with biotin, citric acid or sodium citrate was significantly greater than that in a medium without supplementation. This study provides an effective bioengineering approach for improving the DHA accumulation in oleaginous microbes.

是产油能力最强的二十二碳六烯酸（DHA，22:6）生产菌之一。然而，大多数野生型（WT）菌株的 DHA 产量都不能满足大规模生产的要求。在本研究中，我们采用大气压室温等离子体（ARTP）诱变技术，构建了先前分离得到的一株的突变体文库（即 PKU#Mn4）。两轮 ARTP 诱变结合乙酰辅酶 A 羧化酶（ACCase）抑制剂（噻虫啉）筛选，得到了突变株 A78，该突变株不仅表现出更好的生长、葡萄糖摄取和 ACCase 活性，而且 DHA 含量比 WT 菌株提高了 54.1%。随后对培养基成分进行优化和补充，与在未优化的培养基中培养的突变株 A78 相比，分别提高了 75.5%和 37.2%的 DHA 含量。有趣的是，在添加生物素、柠檬酸或柠檬酸钠的培养基中，突变株 A78 的 ACCase 活性显著高于不添加的培养基。本研究为提高油脂微生物中 DHA 的积累提供了一种有效的生物工程方法。