A RESTRICTION ENZYME FROM HEMOPHILUS-INFLUENZAE .1. PURIFICATION AND GENERAL PROPERTIES
A RESTRICTION ENZYME FROM HEMOPHILUS-INFLUENZAE .1. PURIFICATION AND GENERAL PROPERTIES
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DOI：
10.1016/0022-2836(70)90149-x
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发表时间：
1970-01-01
影响因子：
5.6
通讯作者：
WILCOX, KW
中科院分区：
文献类型：
--
作者：
SMITH, HO;WILCOX, KW
流感嗜血杆菌Rd株的提取物含有一种核酸内切酶活性，它能迅速降低各种外源天然DNA的比粘度;流感病毒DNA在相同条件下不会发生改变。这种“限制性”核酸内切酶活性已经纯化了大约200倍。纯化的酶不含可检测的核酸内切或核酸外切活性。流感病毒DNA然而，以天然噬菌体T7 DNA为底物，它产生约40个双链5′-磷酰基，3′-羟基切割。极限产物的平均长度约为1000个核苷酸对，不含单链断裂。该酶对变性DNA无活性，并且除了镁离子之外不需要特殊的辅因子。
Extracts ofHemophilus influenzaestrain Rd contain an endonuclease activity which produces a rapid decrease in the specific viscosity of a variety of foreign native DNA's; the specific viscosity ofH. influenzaeDNA is not altered under the same conditions. This “restriction” endonuclease activity has been purified approximately 200-fold. The purified enzyme contains no detectable exo- or endonucleolytic activity againstH. influenzaeDNA. However, with native phage T7 DNA as substrate, it produces about 40 double-strand 5′-phosphoryl, 3′-hydroxyl cleavages. The limit product has an average length of about 1000 nucleotide pairs and contains no single-strand breaks. The enzyme is inactive on denatured DNA and it requires no special co-factors other than magnesium ions.