Characterization of a trifunctional fatty acid desaturase from oleaginous filamentous fungus Mortierella alpina 1S-4 using a yeast expression system
Characterization of a trifunctional fatty acid desaturase from oleaginous filamentous fungus Mortierella alpina 1S-4 using a yeast expression system
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DOI：
10.1016/j.jbiosc.2013.05.023
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发表时间：
2013-12-01
影响因子：
2.8
通讯作者：
Ogawa, Jun
中科院分区：
文献类型：
--
作者：
Kikukawa, Hiroshi;Sakuradani, Eiji;Ogawa, Jun
一个参与n-3多不饱和脂肪酸（PUFAs）生物合成的omega -3脂肪酸去饱和酶基因（maw3）先前从高山孢杆菌（Mortierella alpina） s -4中分离得到。在本报告中，我们研究了MAW3在酵母转化过程中与内源性和外源性脂肪酸催化反应的产物。通过GC-MS和H-1 NMR分析，在表达maw3基因的酵母转化中重新合成了两种不同寻常的脂肪酸，分别为n-4十六烯酸（16:2(9cis,12cis)）和n-1十六烯酸（16:3(9cis,12cis,15)）。除了对18碳和20碳PUFAs在omega - 3位置的去饱和活性外，酵母转化中的MAW3在内源性棕榈油酸的Delta - 12位置插入一个双键（16:1(9cis)），并在得到的16:2（9cis,12cis）的Delta - 15位置插入一个双键，形成16:3(9cis,12cis,15)，从而形成一个双功能的Delta 12/Delta 15-去饱和酶，用于16碳脂肪酸。此外，我们还评估了MAW3在酵母转化过程中不同温度下的活性。MAW3在28℃时对M. alpina s -4不具有去饱和活性，但在酵母转化中对多种脂肪酸具有去饱和活性。MAW3被证明是一个三重功能的Delta 12/Delta 15/omega 3-去饱和酶，表现出16:1（9顺式）的Delta 12去饱和，Delta 15对在Delta 12位置有一个预先存在的顺式双键的16-和18-碳脂肪酸去饱和，以及omega 3对在Delta 14位置有一个的20-碳脂肪酸去饱和。这是第一次报道脂肪酸去饱和酶（MAW3）除了其主要功能omega - 3去饱和活性外，还具有16碳脂肪酸的Delta 12-和Delta 15-去饱和活性。(C) 2013，生物技术学会，日本。版权所有。
A omega 3-fatty acid desaturase gene (maw3) which is involved in biosynthesis of n-3 polyunsaturated fatty acids (PUFAs) was previously isolated from Mortierella alpina 1S-4. In this report, we investigated the products of MAW3 catalyzing reaction with endogenous and exogenous fatty acids in the yeast transformant. Two unusual fatty acids de novo synthesized in the yeast transformant expressing maw3 gene were identified as n-4 hexadecadienoic acid (16:2(9cis,12cis)) and n-1 hexadecatrienoic acid (16:3(9cis,12cis,15)) by GC-MS and H-1 NMR analyses. In addition to the desaturation activity at the omega 3-position for 18- and 20-carbon PUFAs, MAW3 in the yeast transformant inserted a double bond at Delta 12-position of endogenous palmitoleic acid (16:1(9cis)) and further at Delta 15-position of the resulting 16:2(9cis,12cis) to result in the formation of 16:3(9cis,12cis,15) leading to a bifunctional Delta 12/Delta 15-desaturase for 16-carbon fatty acids. Moreover, we evaluated the activity of MAW3 in the yeast transformant under different temperatures. The MAW3 did not have desaturation activities in M. alpina 1S-4 at 28 degrees C but it had in the yeast transformant for various fatty acids. The MAW3 was demonstrated to be a trifunctional Delta 12/Delta 15/omega 3-desaturase, exhibiting Delta 12-desaturation for 16:1(9cis), Delta 15-desaturation for 16- and 18-carbon fatty acids that had a preexisting cis-double bond at Delta 12 position, and omega 3-desaturation for 20-carbon fatty acids having that at Delta 14-position. It is the first report that the fatty acid desaturase (MAW3) is shown to have Delta 12- and Delta 15-desaturation activities for a 16-carbon fatty acid, in addition to its major function, omega 3-desaturation activity. (C) 2013, The Society for Biotechnology, Japan. All rights reserved.