A vertebrate fatty acid desaturase with Delta 5 and Delta 6 activities.
A vertebrate fatty acid desaturase with Delta 5 and Delta 6 activities.
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一种具有 Delta 5 和 Delta 6 活性的脊椎动物脂肪酸去饱和酶。
DOI：
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发表时间：
2001
影响因子：
11.1
通讯作者：
A. Teale
中科院分区：
文献类型：
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作者：
N. Hastings;M. Agaba;D. Tocher;M. Leaver;J. Dick;J. Sargent;A. Teale
Δ 5和Δ 6脂肪酸去饱和酶是多不饱和脂肪酸花生四烯酸、二十碳五烯酸和二十二碳六烯酸生物合成途径中的关键酶。它们由哺乳动物和秀丽隐杆线虫中的不同基因编码。从斑马鱼（Danio rerio）中分离到一个与哺乳动物Delta 6去饱和酶基因高度相似的cDNA。这个1,590 bp的序列确定了一种蛋白质，与其他脂肪酸去饱和酶一样，它含有一个N-末端细胞色素B（5）结构域和三个组氨酸盒，据信与催化有关。当斑马鱼cDNA在酿酒酵母中表达时，它赋予了将亚油酸（18：2n-6）和α-亚麻酸（18：3 n-3）转化为其相应的Δ 6去饱和产物18：3 n-6和18：4 n-3的能力。然而，此外，它赋予酵母将二高γ-亚油酸（20：3 n-6）和二十碳四烯酸（20：4 n-3）分别转化为花生四烯酸（20：4 n-6）和二十碳五烯酸（20：5 n-3）的能力，表明斑马鱼基因编码具有Δ 5和Δ 6去饱和酶活性的酶。斑马鱼Delta 5/Delta 6去饱和酶可能代表原型脊椎动物多不饱和脂肪酸生物合成途径的组分。
Delta5 and Delta6 fatty acid desaturases are critical enzymes in the pathways for the biosynthesis of the polyunsaturated fatty acids arachidonic, eicosapentaenoic, and docosahexaenoic acids. They are encoded by distinct genes in mammals and Caenorhabditis elegans. This paper describes a cDNA isolated from zebrafish (Danio rerio) with high similarity to mammalian Delta6 desaturase genes. The 1,590-bp sequence specifies a protein that, in common with other fatty acid desaturases, contains an N-terminal cytochrome b(5) domain and three histidine boxes, believed to be involved in catalysis. When the zebrafish cDNA was expressed in Saccharomyces cerevisiae it conferred the ability to convert linoleic acid (18:2n-6) and alpha-linolenic acid (18:3n-3) to their corresponding Delta6 desaturated products, 18:3n-6 and 18:4n-3. However, in addition it conferred on the yeast the ability to convert di-homo-gamma-linoleic acid (20:3n-6) and eicosatetraenoic acid (20:4n-3) to arachidonic acid (20:4n-6) and eicosapentaenoic acid (20:5n-3), respectively, indicating that the zebrafish gene encodes an enzyme having both Delta5 and Delta6 desaturase activity. The zebrafish Delta5/Delta6 desaturase may represent a component of a prototypic vertebrate polyunsaturated fatty acids biosynthesis pathway.