Open AccessEndonuclease Activity Associated with the DNA · Protein Complex of Minicircular DNA of Escherichia coli 15
Author(s) -
Messing Joachim,
Staudenbauer Walter L.,
Hofschneider Peter Hans
Publication year - 1973
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1973.tb02882.x
Subject(s) - dna , divalent , dna supercoil , escherichia coli , endonuclease , dna clamp , dna replication , chemistry , biophysics , biology , circular bacterial chromosome , biochemistry , rna , microbiology and biotechnology , gene , reverse transcriptase , organic chemistry
The DNA · protein complex (form I*) of minicircular DNA of Escherichia coli has associated with it an endonucleolytic activity which converts the supercoiled form I into an open circular form II by introducing one single‐stranded break per molecule. This nick can occur with similar frequency in either strand. Prolonged incubation results in the formation of linear duplex molecules (form III). The endonuclease requires a divalent cation (Mg 2+ or Mn 2+ ) and is inhibited by high salt concentration and transfer RNA. It might provide a swivel mechanism during the replication of minicircular DNA.