菊粉酶基因克隆表达与油脂的组分分析

为了实现解脂亚罗威亚酵母（Yarrowia lipolytica）直接利用菊粉进行油脂生产，将外切菊粉酶基因INU1与表达质粒pINA1317连接，在解脂亚罗威亚酵母（Y. lipolytica）ACA-DC尿嘧啶缺陷突变菌株中表达。以尿嘧啶缺陷型筛选作为筛选标记获得转化子C37，经过培养菊粉酶酶活达到37.15 U/mL。在2 L发酵罐中，转化子C37以菊粉为底物进行发酵，油脂产量和细胞干质量分别为49%和14 g/L。脂肪酸分析结果显示棕榈酸、硬脂酸和油酸总和占总脂肪酸的92%以上，其中油酸含量高达59%，表明通过菊粉酶基因在解脂亚罗威亚酵母中的表达，实现了以菊粉为底物一步发酵产单细胞油脂。

Cloning and expression of inulinase gene and analysis of oil components

In order to realize oil production directly from inulin by Yarrowia lipolytica, exoinulinase gene INU1 was connected with expression plasmid pINA1317 and expressed in mutant strain Y. lipolytica ACA-DC with uracil deficiency. With uracil deficiency as selection marker, transformant C37 was obtained and the inulase activity was up to 37.15 U/ml by culture. In 2 L fermenter, transformant C37 was fermented with inulin as substrate, the oil yield and cell dry mass were 49% and 14 g/L, respectively. The results of fatty acids analysis showed that the total contents of palmitic acid, stearic acid and oleic acid were more than 92% of total fatty acids, and the oleic acid content was up to 59%, which indicated that the one-step fermentation was realized to produce single cell oil with inulin through the expression of the inulinase gene in Y. lipolytica.