An endonuclease induced after infection of Escherichia coli with bacteriophage T7. I. Purification and properties of the enzyme.
نویسندگان
چکیده
A deoxyribonuclease has been purified 1,800-fold from Escherichia coli infected with bacteriophage T7. The enzyme has an approximate molecular weight of 18,000, requires a divalent cation for activity, and is inhibited by high concentrations of RNA. The purified enzyme catalyzes an endonucleolytic cleavage of both singleand double-stranded DNA. The rate of hydrolysis of single-stranded DNA is 150-fold that of double-stranded DNA. The hydrolysis of single-stranded DNA results in the formation of acid-soluble oligonucleotides. No acid-soluble products have been observed during the hydrolysis of double-stranded DNA. Identity of the activities toward singleand double-stranded DNA is supported by identical sedimentation rates in sucrose gradients, reaction requirements, rates of heat inactivation, and genetic analysis.
منابع مشابه
Bacteriophage T7 endonuclease. I. Properties of the enzyme purified from T7 phage-infected Escherichia coli B.
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عنوان ژورنال:
- The Journal of biological chemistry
دوره 245 23 شماره
صفحات -
تاریخ انتشار 1970