核糖核苷酸对大鼠肠黏膜细胞质组分中DNA聚合酶测定底物可用性的影响。

Effect of ribonucleotides on substrate availability for DNA polymerase assays in cytoplasmic fractions of rat intestinal mucosa.

作者信息

Zbarsky S H, Chevalier S

出版信息

Can J Biochem. 1977 Apr;55(4):489-92. doi: 10.1139/o77-069.

Abstract

The deoxyribonucleoside triphosphate substrates for DNA synthesis were hydrolysed during the DNA polymerase (EC 2.7.7.7) assay with cytoplasmic subcellular fractions of rat intestinal mucosa. Presumably because of phosphatase (EC 3.1.3.2) activity in these fractions, inorganic phosphate was liberated from the nucleotides, and radioactive thymidine triphosphate was shown to be degraded to thymidine di-and mono-phosphate, thymidine, and thymine. Addition of ATP to the postmicrosomal supernatant increased its DNA polymerase activity by sparing the deoxyribonucleotide precursors from enzymatic degradation.

摘要

在使用大鼠肠黏膜细胞质亚细胞组分进行DNA聚合酶（EC 2.7.7.7）测定的过程中，用于DNA合成的脱氧核糖核苷三磷酸底物发生了水解。推测是由于这些组分中存在磷酸酶（EC 3.1.3.2）活性，核苷酸释放出无机磷酸盐，并且放射性三磷酸胸腺嘧啶核苷被证明降解为二磷酸胸腺嘧啶核苷、单磷酸胸腺嘧啶核苷、胸腺嘧啶核苷和胸腺嘧啶。向后微粒体上清液中添加ATP，通过使脱氧核苷酸前体免受酶促降解，提高了其DNA聚合酶活性。