The synthesis of murine ferrochelatase in vitro and in vivo.
The synthesis of murine ferrochelatase in vitro and in vivo.
复制标题
鼠亚铁螯合酶的体外和体内合成。
DOI：
10.1042/bj2540799
复制
发表时间：
1988
期刊：
影响因子：
--
通讯作者：
Dailey,HA
中科院分区：
文献类型：
--
作者：
Karr,SR;Dailey,HA
铁络合酶(Protohaem Ferro-lyase，EC 4.99.1.1)是血色素生物合成途径的终末酶，是线粒体内膜的一种完整的膜蛋白。用[35S]蛋氨酸活体标记小鼠红白血病细胞，裂解，提取液与兔抗(鼠)铁络合酶抗体免疫共沉淀，分离得到一种分子量为40,000的蛋白质。然而，当分离的小鼠RNA被翻译成无细胞的网织红细胞提取物时，就分离出了一种Mr为43,000的蛋白质。将这一MR 43,000蛋白质与分离的线粒体孵育，结果加工出MR 40,000成熟大小蛋白质的MR 43,000前体。添加羰基氰化物、间氯苯肼和/或邻菲咯啉可抑制这一过程。这些数据表明，像大多数线粒体蛋白质一样，铁络合酶是在细胞质中作为较大的前体合成的，然后在一个需要能量的步骤中被转移和加工成成熟大小的蛋白质。
Ferrochelatase (protohaem ferro-lyase, EC 4.99.1.1), the terminal enzyme of the haem-biosynthetic pathway, is an integral membrane protein of the mitochondrial inner membrane. When murine erythroleukaemia cells are labelled in vivo with [35S]methionine, lysed, and the extract is immunoprecipitated with rabbit anti-(mouse ferrochelatase) antibody, a protein of Mr 40,000 is isolated. However, when isolated mouse RNA is translated in a cell-free reticulocyte extract, a protein of Mr 43,000 is isolated. Incubation of this Mr 43,000 protein with isolated mitochondria resulted in processing of the Mr 43,000 precursor to the Mr 40,000 mature-sized protein. Addition of carbonyl cyanide m-chlorophenylhydrazone and/or phenanthroline inhibits this processing. These data indicate that ferrochelatase, like most mitochondrial proteins, is synthesized in the cytoplasm as a larger precursor and is then translocated and processed to a mature-sized protein in an energy-required step.