Stereospecificity of the products of the fatty acid oxygenases derived from psoriatic scales.
Stereospecificity of the products of the fatty acid oxygenases derived from psoriatic scales.
复制标题
源自银屑病鳞屑的脂肪酸加氧酶产物的立体特异性。
作者：
A. Baer;P. Costello;F. Green
银屑病皮肤鳞屑中花生四烯酸和亚油酸的主要体内加氧酶产物是12-羟基二十碳四烯酸（R/S = 5.7）、13-羟基十八碳二烯酸（S/R = 1.9）和9-羟基十八碳二烯酸（R/S = 2.4）。定义这些脂肪酸衍生物的酶来源是评估其在银屑病发病机制中可能作用的重要步骤。银屑病皮肤鳞片与放射性标记的花生四烯酸和亚油酸孵育，并在体外产生的单羟基衍生物进行了表征。与[3 H]花生四烯酸孵育的产物是对映体纯的15（S）-[3 H]羟基二十碳四烯酸和12-[3 H]羟基二十碳四烯酸立体异构体的非外消旋混合物（R/S比= 4.5）。从[14 C]亚油酸制备对映体纯的13（S）-[14 C]羟基十八碳二烯酸。与热变性鳞片孵育后未产生放射性标记产物。这些结果为银屑病皮肤鳞屑中保留的两种不同的加氧酶活性提供了证据。一种是具有严格（S）立体特异性的ω-6加氧酶，与脂氧合酶的活性一致。这种酶的活性似乎与在培养的人角质形成细胞中描述的15-脂氧合酶的活性相似。第二种活性是花生四烯酸12（R）-加氧酶的活性，其在正常人表皮中未观察到，但似乎在银屑病表皮中表达。
The principal in vivo oxygenase products of arachidonic acid and linoleic acid in psoriatic skin scales are 12-hydroxyeicosatetraenoic acid (R/S ratio = 5.7), 13-hydroxyoctadecadienoic acid (S/R = 1.9), and 9-hydroxyoctadecadienoic acid (R/S = 2.4). Definition of the enzymatic origin of these fatty acid derivatives is an important step in assessing their possible role in the pathogenesis of psoriasis. Psoriatic skin scales were incubated with radiolabeled arachidonic acid and linoleic acid and the monohydroxylated derivatives produced in vitro were characterized. The products of incubation with [3H]arachidonic acid were an enantiopure 15(S)-[3H]hydroxyeicosatetraenoic acid and a nonracemic mixture of the 12-[3H]hydroxyeicosatetraenoic acid steroisomers (R/S ratio = 4.5). An enantiopure 13(S)-[14C]hydroxyoctadecadienoic acid was produced from [14C]linoleic acid. No radiolabeled products were derived from incubations with heat-denatured scales. These results provide evidence for two distinct oxygenase activities that are preserved in psoriatic skin scales. One is that of an omega-6 oxygenase with strict (S) stereospecificity, consistent with the activity of a lipoxygenase. This enzyme activity appears to be similar to that of the 15-lipoxygenase which has been described in cultured human keratinocytes. The second activity is that of an arachidonic acid 12(R)-oxygenase that has not been observed in normal human epidermis but which appears to be expressed in psoriatic epidermis.
海胆（Strongylocentrotus purpuratus）的卵含有显着的 (11R) 和 (12R) 脂氧合酶活性。
DOI：
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发表时间：
1987
期刊：
The Journal of biological chemistry
影响因子：
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作者：
Hawkins,DJ;Brash,AR
通讯作者：
Brash,AR