Diczfalusy U, Alexson S E
Department of Clinical Chemistry I, Huddinge University Hospital, Sweden.
J Lipid Res. 1988 Dec;29(12):1629-36.
We have recently reported that prostaglandin F2 alpha can be chain-shortened by isolated rat liver peroxisomes. In the present study it is further established by cell fractionation experiments that the enzymes involved in this reaction are localized to peroxisomes. Under the conditions employed, the highest activity was found in the light mitochondrial fraction. Further fractionation of the light mitochondrial fraction by sucrose density gradient centrifugation showed that the prostaglandin oxidation activity comigrated with peroxisomal marker enzymes. Di(2-ethylhexyl)phthalate treatment resulted in a tenfold increased capacity for the conversion of prostaglandin F2 alpha into tetranorprostaglandin F1 alpha. The reaction was not inhibited by KCN. The reaction was further characterized with respect to cofactor requirements. The prostaglandin oxidation was found to be completely dependent on NAD, CoA, ATP, Mg2+ and was stimulated by FAD. Incubation of prostaglandin E2 with peroxisomes resulted in conversion into several products. After alkaline hydrolysis, one of these was identified as tetranorprostaglandin B1.
我们最近报道，前列腺素F2α可被分离的大鼠肝脏过氧化物酶体缩短碳链。在本研究中，通过细胞分级分离实验进一步证实，参与该反应的酶定位于过氧化物酶体。在所采用的条件下，在轻线粒体部分发现了最高活性。通过蔗糖密度梯度离心对轻线粒体部分进行进一步分级分离表明，前列腺素氧化活性与过氧化物酶体标记酶共迁移。邻苯二甲酸二（2-乙基己基）酯处理使前列腺素F2α转化为四去甲前列腺素F1α的能力提高了十倍。该反应不受KCN抑制。进一步研究了该反应对辅因子的需求。发现前列腺素氧化完全依赖于NAD、CoA、ATP、Mg2+，并受到FAD的刺激。前列腺素E2与过氧化物酶体孵育会转化为几种产物。碱性水解后，其中一种被鉴定为四去甲前列腺素B1。
