p1. Polynucleotide phosphorylase was partially purified from the inner membrane of rat liver mitochondria. 2. The partially purified particulate enzyme catalyses phosphorolysis of poly(A), poly(C), poly(U) and RNA to nucleoside diphosphates. 3. It is devoid of nucleoside diphosphate-polymerization activity. 4. Variable amounts of ADP/Psubi/sub-exchange activity are associated with the polynucleotide phosphorylase and are probably due to a different enzyme. 5. ADP is the preferred substrate for exchange, and little or no reaction occurs with other nucleoside diphosphates, but ATP/Psubi/sub-exchange takes place at one-third the rate observed with ADP. 6. The partially purified enzyme is free from the phosphatases found in the crude mitochondrial inner membrane, but is associated with an endonuclease activity and some adenylate kinase activity; no cytidylate kinase activity analogous to the latter was detectable./p
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机译:> 1。从大鼠肝脏线粒体的内膜中部分纯化了多核苷酸磷酸化酶。 2.部分纯化的颗粒酶催化聚(A),聚(C),聚(U)和RNA磷酸化为核苷二磷酸。 3.它没有核苷二磷酸的聚合活性。 4.可变数量的ADP / P i sub>交换活性与多核苷酸磷酸化酶有关,可能是由于不同的酶。 5. ADP是交换的首选底物,与其他核苷二磷酸几乎没有反应,甚至没有反应,但是ATP / P i sub>交换的发生率是ADP观察到的三分之一。 6.部分纯化的酶不含线粒体内膜中的磷酸酶,但与核酸内切酶活性和一些腺苷酸激酶活性有关;没有检测到与后者相似的胞苷酸激酶活性。 p>
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