核酸酶P1的分离纯化及部分酶学性质研究

Purification and Partial Enzymological Properties of Nuclease P1

桔青霉发酵液经离心、超滤、硫酸铵盐析、透析和DE-52型树脂柱色谱分离,纯化得到核酸酶P1。比活为28490u/mg,纯化10.5倍,收率为45%。SDS-PAGE电泳显示为单一条带。酶学性质研究结果表明,以酵母RNA为底物时的Km为3.36mmol/L,最适作用温度70℃,最适pH5.4。

The nuclease P1 was purified from fermentation broth of Penicillium citrinum by centrifugation, ultrafiltration, ammonium sulfate precipitation, dialysis and chromatography by DE-52 resin. The purity of the enzyme was increased 10.5 fold with the specific activity of 28490u/mg and 45% yield. The purified enzyme showed a single protein band on SDS-PAGE. The study on enzymological properties of nuclease P1 showed that the Km was 3.36mmol/L with yeast RNA as the substrate. The optimal reaction temperature and pH of the enzyme were 70℃ and 5.4, respectively.