Open AccessReplication of Colicin E1 Plasmid DNA in Minicells from a Unique Replication Initiation Site
Author(s) -
Joseph Inselburg
Publication year - 1974
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.71.6.2256
Subject(s) - dna replication , endonuclease , cleavage (geology) , origin recognition complex , replication factor c , plasmid , dna , control of chromosome duplication , biology , restriction enzyme , colicin , origin of replication , prokaryotic dna replication , eukaryotic dna replication , microbiology and biotechnology , genetics , paleontology , fracture (geology)
Replicating DNA molecules of the colicin E1 plasmid isolated from minicells are cleaved at a single site by R1 restriction endonuclease (Eco R1). Electron microscopic measurements of the replicating molecules treated with the endonuclease indicate that (a ) replication is initiated at a site between 14% and 20% of the distance from theEco R1 endonuclease cleavage site; and (b ) extensive replication of most molecules occurs in one direction from the initiation site, although a limited amount of replication in the opposite direction may occur. Single-stranded regions at one or both replication forks, involving one or both DNA strands, can be frequently found in replicating molecules.