Identity of Phosphodiesterase and Phosphomonoesterase Activities with Nuclease P1 (a Nuclease from Penicillium citrinum)
Identity of Phosphodiesterase and Phosphomonoesterase Activities with Nuclease P1 (a Nuclease from Penicillium citrinum)
复制标题
核酸酶 P1（来自柑橘青霉的核酸酶）对磷酸二酯酶和磷酸单酯酶活性的鉴定
DOI：
10.1271/bbb1961.38.785
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发表时间：
1974
期刊：
影响因子：
--
通讯作者：
H. Yoshino
中科院分区：
文献类型：
--
作者：
M. Fujimoto;A. Kuninaka;H. Yoshino
研究了纯化青霉菌核酸酶（称为核酸酶 P1）的酶学特性。 RNA、热变性 DNA、天然 DNA、3′-AMP 和 2′-AMP 的酶活性在以下特性方面表现出很大程度的相似性：a) 稳定 pH 范围 (5~8)，b) 最适温度（70°C 左右），c) 热稳定性（67°C，pH 6.0 15 分钟约 50% 失活，d）金属离子和 SH 抑制剂的影响，e） Zn2+，f) 白蛋白和 Zn2+ 防止热失活，g) 寒冷时失活和加热时重新激活，h) 对蛋白酶的敏感性，i) 酶反应中底物之间的竞争关系。此外，几种柑橘青霉突变体的酶活性比率是恒定的。根据这些结果，加上整个纯化过程中比活性的恒定比率，可以得出结论：单一酶可能负责磷酸二酯酶和磷酸单酯酶的功能。
Enzymatic properties of a purified Penicillium nuclease (designated as nuclease P1) were investigated. The enzyme activities for RNA, heat-denatured DNA, native DNA, 3′-AMP and 2′-AMP showed a great degree of similarity with respect to the following properties: a) Range of stable pH (5~8), b) temperature optima (at around 70°C), c) thermostability (about 50% inactivation at 67°C, pH 6.0 for 15 min, d) effect of metal ions and SH inhibitors, e) requirement of Zn2+, f) protection from the heat-inactivation by albumin and Zn2+, g) inactivation on standing in the cold and reactivation on heating, h) sensitivity to protease, and i) competitive relationship between substrates in the enzyme reaction. Moreover, the ratio of enzyme activities in several mutants of Penicillium citrinum was constant. From these results, together with constant ratio of the specific activities throughout purification, it is concluded that a single enzyme might be responsible for both phosphodiesterase and phosphomonoesterase functions.