Inhibition of ribonucleoside diphosphate reductase by hydroxyurea.
Inhibition of ribonucleoside diphosphate reductase by hydroxyurea.
复制标题
羟基脲抑制核糖核苷二磷酸还原酶。
作者：
I. Krakoff;N. Brown;P. Reichard
羟基脲是一种抑制动物和人体内快速增殖组织生长的化合物，已知它能抑制DNA合成，对原油系统的研究表明，羟基脲的作用是通过阻止核糖核苷酸还原为脱氧核糖核苷酸来实现的。
Hydroxyurea, a compound which inhibits the growth of rapidly proliferating tissues in animals and man, is known to inhibit DNA synthesis, and studies in crude systems have indicated that it does so by preventing the reduction of ribonucleotides to deoxyribonucleotides.
This study demonstrates hydroxyurea-induced inhibition of the reduction of ribonucleotides by a highly purified enzyme system from Escherichia coli B. The inhibition (70% at 3 × 10-3 m under standard incubation conditions) is dependent on the concentration of hydroxyurea and on the duration of exposure of the enzyme to hydroxyurea. The effect of hydroxyurea is specific for protein B2 of the ribonucleoside diphosphate reductase system. The inhibition of enzymatic activity is apparently irreversible, although there is negligible irreversible binding of 14C-labeled hydroxyurea to the enzyme protein.