槐糖脂合成过程中关键酶的研究进展

Research Progress on the Key Enzymes in the Process of Sophorolipids Synthesis

槐糖脂合成过程中的关键酶包括细胞色素P450、葡萄糖基转移酶、甘油醛-3-磷酸脱氢酶、内酯化酶和乙酰基转移酶。细胞色素P450的作用是将脂肪酸末端羟基化,是槐糖脂合成中的第一个关键酶。目前已经探究出CYP450及它们相应的还原酶,NADpH细胞色素P450还原酶,限制了烷烃和脂肪酸的ω氧化速率。葡萄糖基转移酶1将一分子葡萄糖转移到羟基脂肪酸的末端或近末端,形成葡萄糖脂。另一个葡萄糖分子在葡萄糖基转移酶2的作用下转移到葡萄糖脂上形成酸型槐糖脂。目前已经确认了一种葡萄糖转移酶基因:UGTB1,在槐糖脂合成过程中的糖基化中起了关键性的作用。甘油醛-3-磷酸脱氢酶作用是用于ATP形成和为细胞添加能量。酸型槐糖脂在一种内酯化酶的作用下将脂肪酸的羧基和槐糖4″位的羟基酯化形成内酯型槐糖脂。这种内酯化酶对于定向合成不同类型的槐糖脂具有非常重要的作用,它与南极脂肪酶A的具有同源性,经过研究表明lipase1就是将酸性槐糖脂内酯化反应的酶。乙酰基转移酶负责槐糖脂的乙酰化,对槐糖脂的修饰具有重要作用。

Several key enzymes played a very important role in synthesis of sophorolipids, including P450, UDP- glucosyltransferase, GPD, esterification enzyme, acetylase. Cytochrome P450 hydroxylated the end of fatty acids. It was the first key enzemy in the synthesis of sophorolipids. P450 restricted the oxidation rate of alkane and fatty acids. CYP52E3 and CYP52N1 have no relation with the synthesis of sophorolipids. UDP-glucosyltransferase transformed glucose into end of fatty acids. Now, the gene of glucosyltransferase ： UGTB1 was confirmed. And UGTB1 played an important role in glycosylation. GPD could provide energy to cells. Esterification enzyme made acid sophorolipids to lactone sophorolipids. Esterification enzyme was important to synthesize different sophorolipids. Acetylase was responsible for acetylation of sophorolipids.lt was important for modification of sophorolipids.