摘要
γ－亚麻酸（ＧＬＡ，Ｃ１８：３△６，９，１２）是由△６－脂肪酸脱氢酶以亚油酸（ＬＡ，Ｃ１８：２△９，１２）为底物，在Ｃ６位脱氢形成的。由于在人体中，γ－亚麻酸是花生四烯酸、前列腺素类和白三烯类等生理活性物质的前体物，而深黄被孢霉是目前用于微生物发酵生产γ－亚麻酸的主要菌株。本文根据脂肪酸脱氢酶的保守区设计引物，利用反转录聚合酶链式反应从丝状真菌深黄被孢霉中克隆了编码△６－脂肪酸脱氢酶的ｃＤＮＡ，全长为１３７４个核苷酸，编码４５７ 个氨基酸，但与其他位点的脂肪酸脱氢酶不同的是， △６－脂肪酸脱氢酶在其序列的 Ｎ 端特有细胞色素 ｂ５（Ｃｙｔｂ５）区。这是国际上对深黄被孢霉△６－脂肪酸脱氢酶基因的首次报道。
r -Lindenic acid (GLA, C18:3△6,9,12) is synthesized by △6-fatty acid desaturase using linoleic acid (LA, C 18:2△9,12) as a substrate by dehydrogenation in carbon 6. In human bodies, it is known to be Precursors of arachidonic acid, prostaglandins and leukotrienes. Mortierella isabellina is the main strain producing r -Lindenic acid by fermentation. We have isolated a cDNA encoding the △6-fatty acid desaturase from M isabellina via a polymerase chain reaction-based strategy using primers designed to the conserved regions of known △6-desaturase genes. The full-length cDNA fragment consists of 1374 nucleotides encoding 457 amino acids and differs from other position desaturases by the presence of an N-terminal domain related to cytochrome b5. This is the first report that △6-fatty acid desaturase gene from M isabellina is cloned in the world.
出处
《菌物系统》
CAS
CSCD
北大核心
2001年第1期44-50,共7页
Mycosystema
基金
国家自然科学基金项目!(39870020)
天津市自然科学基金项目!(973607611)
