Biopolym. Cell. 1986; 2(6):317-322.
Structure and Function of Biopolymers
Supercoiled dna as a substrate for detection of endonucleolytic activities in commercial and laboratory biochemical preparations
1Drygin Yu. F., 1Zuklys K. L.
  1. M. V. Lomonosov State University
    Moscow, USSR


Supercoiled DNA is known to be a sensitive substrate for detecting the endonucleolytic activity. Supercoiled pBR322 and other ColE1-related plasmids are shown to be highly useful both for detecting nonspecific endonucleolytic admixtures in many biochemical preparations and for comparative estimation of certain DNAses and RNAses activity.
More than 30 enzymes, proteins and chemical substances (salts, sucrose, eys.) commonly used for nuclear acids and nucleoproteins structural study are analyzed. Certain commercial praparation of proteolytic enzymes, kinases, ligases, polymerases, etc. are found to contain a detectable level of the endonucleolytic activity


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