Catalytic Production of Oxo-fatty Acids by Lipoxygenases Is Mediated by the Radical–Radical Dismutation between Fatty Acid Alkoxyl Radicals and Fatty Acid Peroxyl Radicals in Fatty Acid Assembly
作者:Yuta Takigawa、Ichiro Koshiishi
DOI:10.1248/cpb.c19-00975
日期:2020.3.1
(E/Z)-HpODEs to an (E/Z)-linoleate alkoxyl radical through one-electron reduction. Taken together, we propose that (E/Z)-OxoODEs and (E/E)-HpODEs are produced through radical-radical dismutation between (E/Z)-linoleate alkoxyl radical and (E/E)-linoleate peroxyl radical. Furthermore, the production of (E/Z)-OxoODEs and (E/E)-HpODEs was remarkably inhibited by a hydrophobic radical scavenger, 2,2,6,6-tetramethylpiperidine
氧十八碳二烯酸(OxoODE)在生物学上起过氧化物酶体增殖物激活受体(PPAR)激动剂的作用,并且已知在脂氧合酶/亚油酸酯系统中产生。OxoODE似乎源自亚油酸脂氧合酶催化的拟过氧化物酶反应,由亚油酸(E / Z)-氢过氧十八碳二烯酸((E / Z)-HpODEs)生成的亚油酸酯烷氧基自由基。然而,烷氧基自由基转化为OxoODE的机制仍然不清楚。在本研究中,我们确认了氧代氧化酶在脂氧合酶/亚油酸酯系统中以氧依赖性方式产生。有趣的是,我们揭示了系统中(E / Z)-OxoODE含量与(E / E)-HpODEs含量之间的相关性。(E / E)-HpODEs可能来自(E / E)-亚油酸酯过氧自由基,它们是由亚油酸烯丙基酯自由基与氧分子之间的反应产生的。值得注意的是,脂氧合酶-亚油酸亚铁基烯丙基(LOx(Fe2 +)-L·)络合物是脂氧合酶/亚油酸酯系统中的中间体,趋于离解为LOx(Fe2 +)和亚油酸烯丙基。随后,LOx(Fe2