ANALYSIS OF A SPECIFIC OXYGENATION REACTION OF SOYBEAN LIPOXYGENASE-1 WITH FATTY-ACIDS ESTERIFIED IN PHOSPHOLIPIDS
ANALYSIS OF A SPECIFIC OXYGENATION REACTION OF SOYBEAN LIPOXYGENASE-1 WITH FATTY-ACIDS ESTERIFIED IN PHOSPHOLIPIDS
复制标题
DOI：
10.1021/bi00391a038
复制
发表时间：
1987-08-25
期刊：
影响因子：
2.9
通讯作者：
HARRIS, TM
中科院分区：
文献类型：
--
作者：
BRASH, AR;INGRAM, CD;HARRIS, TM
大豆脂肪氧合酶与磷脂酰胆碱（在pH 9，与10 mM脱氧胆酸盐）反应，并通过高压液相色谱，紫外，气相色谱-质谱（GC-MS），和NMR分析的氧化产物。通过磷脂酶C水解回收的甘油二酯的GC-MS和完整磷脂酰胆碱的质子NMR建立完整的甘油脂质产物的结构。这些分析以及酯交换脂肪酸的分析表明，磷脂酰胆碱中的花生四烯酰基和亚油酰基部分仅分别转化为15（S）-氢过氧基-5（Z），8（Z），11（Z），13（E）-二十碳四烯酸酯和13（S）-氢过氧基-9（Z），11（E）-十八碳二烯酸酯类似物。对照实验证明，完整的磷脂（和未水解/再酯化的脂肪酸）是氧化反应的真正底物。磷脂酰乙醇胺和磷脂酰肌醇脂类也是大豆脂氧合酶特异性氧化的底物。结果提供了具体的证据表明，在磷脂中酯化的脂肪酸可以通过脂氧合酶进行高度特异性的氧化。
Soybean lipoxygenase was reacted with phosphatidylcholine (at pH 9, with 10 mM deoxycholate), and the oxygenation products were analyzed by high-pressure liquid chromatography, UV, gas chromatography-mass spectrometry (GC-MS), and NMR. The structures of the intact glycerolipid products were established by GC-MS of diglycerides recovered by phospholipase C hydrolysis and by proton NMR of the intact phosphatidylcholine. These analyses, together with analyses of the transesterified fatty acids, indicated that arachidonyl and linoleoyl moieties in the phosphatidylcholine were converted exclusively to the 15(S)-hydroperoxy-5(Z),8(Z),11(Z),13(E)-eicosatetraenoate and 13(S)-hydroperoxy-9(Z),11(E)-octadecadienoate analogues, respectively. Control experiments proved that the intact phospholipid (and not hydrolyzed/reesterified fatty acid) was the true substrate of the oxygenation reaction. Phosphatidylethanolamine and phosphatidylinositol lipids were also substrates for specific oxygenation by the soybean lipoxygenase. The results provide concrete evidence that fatty acids esterified in phospholipid can be subject to highly specific oxygenation by a lipoxygenase enzyme.