利用脂肪酸合成酶抑制剂和磷酸香草醛反应筛选高产油脂酵母菌

Selection of Yeast High in Lipids-yield by Fatty Acid Synthetase Inhibitor and Phosphoric Acid-vanillin Reaction

摘要:

利用80 MeV/u碳离子束对产油菌株粘红酵母进行辐照诱变, 采用含有脂肪酸合成酶抑制剂cerulenin的培养基进行高产油脂突变株的初筛, 并通过磷酸香草醛反应和氯仿甲醇抽提法对初筛菌株油脂含量进行分析。结果表明, cerulenin对酵母细胞生长有较好的抑制作用, 浓度为8.96×10-6 mol/L时, 抑制率达98%以上, 可作为筛选浓度。通过磷酸香草醛反应法对初筛菌体油脂含量进行定量分析, 发现菌体油脂含量与该反应在530 nm处的光吸收成线性正相关, 初筛菌株的正突变率达65%以上。该方法快速方便, 是一种较为理想的产油酵母筛选方法。通过该方法, 筛选出了2株油脂含量高于对照90%以上的突变株。

关键词:微生物油脂, 脂肪酸合成酶, Cerulenin, 磷酸香草醛反应

Abstract:

Rhodotorula glutinis (Fresenius) Harrison was irradiated with 80 MeV/u carbon ions. primary selection of yeast high in lipids-yield was performed with culture medium supplemented cerulenin, an inhibitor of fatty acid synthetase (FAS). The quantity of the lipids of selected strains was analyzed by phosphoric acid-vanillin reaction and traditional methanol-chloroform extraction methods. The results showed that the growth of Rhodotorula glutinis (Fresenius) could be inhibited efficiently by cerulenin. The inhibition rate was up to 98% at cerulenin concentration of 8.96×10-6 mol/L, which was considered suitable for mutant selection. Through the phosphoric acid-vanillin reaction, it was found that the quantity of the lipids was a positive linear relation with the OD at 530 nm. The positive mutant rate of primary selection reached to 65%. With the advantage of rapid and easy to perform, it can be considered as a good method to select yeast high in lipid-yield. By these methods, 2 mutant strains with lipid yield improved 90% compared with control was selected out.

Key words:Microbial lipids, Fatty acid synthetase (FAS), Cerulenin, Phosphoric acid-vanillin reaction