Reddanna P, Whelan J, Reddy P S, Reddy C C
Department of Veterinary Science, Pennsylvania State University, University Park 16802.
Biochem Biophys Res Commun. 1988 Dec 30;157(3):1348-51. doi: 10.1016/s0006-291x(88)81023-4.
An unique membrane bound lipoxygenase was isolated and purified from purple star tulip bulbs with a specific activity of 5.2 mu moles O2 consumed.min-1.mg-1 protein. The purified tulip enzyme exhibits regiospecificity for O2 insertion at C-5 of the arachidonic acid molecule. Identification of the reaction product was confirmed as 5-hydroperoxyeicosatetraenoic acid by analytical criteria which included: cochromatography with the authentic compound, as well as mass spectral and 1H-NMR analysis. Thus, the enzyme from tulip bulbs appears to be different from the cytosolic lipoxygenase from potato tubers, which exhibits non-regiospecificity in terms of O2 incorporation. However, the purified tulip lipoxygenase showed a strong immunological crossreactivity with antiserum raised against the purified potato lipoxygenase, indicating close immunological relationship with the other plant lipoxygenases.
从紫色郁金香球茎中分离并纯化出一种独特的膜结合脂氧合酶，其比活性为5.2微摩尔O₂消耗·分钟⁻¹·毫克⁻¹蛋白质。纯化后的郁金香酶对花生四烯酸分子的C-5位氧插入具有区域特异性。通过包括与标准品共色谱以及质谱和¹H-NMR分析在内的分析标准，确认反应产物为5-氢过氧化二十碳四烯酸。因此，郁金香球茎中的酶似乎与马铃薯块茎中的胞质脂氧合酶不同，后者在氧掺入方面表现出非区域特异性。然而，纯化后的郁金香脂氧合酶与针对纯化的马铃薯脂氧合酶产生的抗血清表现出强烈的免疫交叉反应，表明与其他植物脂氧合酶有密切的免疫关系。
