Vakil B V, Ramakrishnan N, Pradhan D S
Arch Microbiol. 1984 Oct;139(2-3):240-4. doi: 10.1007/BF00402007.
Besides the well-known heat-stable extracellular staphylococcal nuclease (EC 3.1.4.7) and cell surface bound nuclease, one more nuclease, which is heat-labile, has been identified and purified on phosphorylated cellulose column and characterized. Analyses by Sephadex G-75 gel chromatography indicates that the heat-labile cellular nuclease has molecular weight of about 16,000 similar to those of extracellular and cell-surface bound nucleases. Like the heat-stable nucleases, the heat-labile enzyme acts on both DNA and RNA, is more active on heat-denatured DNA, requires Ca2+ ions for activity and maximum catalytic activity is observed at pH 9.8-10 and at 45 degrees C. The results suggest that the three enzymes have properties strikingly similar to one another and therefore may be related structurally.
除了众所周知的热稳定细胞外葡萄球菌核酸酶（EC 3.1.4.7）和细胞表面结合核酸酶外，另一种热不稳定核酸酶已被鉴定出来，并在磷酸化纤维素柱上进行了纯化和表征。通过Sephadex G-75凝胶过滤分析表明，这种热不稳定细胞核酸酶的分子量约为16,000，与细胞外和细胞表面结合核酸酶的分子量相似。与热稳定核酸酶一样，这种热不稳定酶作用于DNA和RNA，对热变性DNA的活性更高，活性需要Ca2+离子，在pH 9.8-10和45℃时观察到最大催化活性。结果表明，这三种酶的性质彼此极为相似，因此在结构上可能相关。
