Open AccessReplication of Colicinogenic Factor El in Escherichia coli
Author(s) -
Sherratt David J.,
Helinski Donald R.
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.tb02962.x
Subject(s) - replication factor c , dna replication , plasmid , replication (statistics) , biology , dna supercoil , microbiology and biotechnology , escherichia coli , dna , chloramphenicol , origin of replication , control of chromosome duplication , chemistry , biophysics , genetics , bacteria , gene , virology
Replication of the colicinogenic factor E1 (Col E1) has been studied in exponentially growing cells and in cells treated with chloramphenicol. Whereas about 80% of non‐replicating Co1E1 DNA is isolated from the cytoplasm, the membrane fraction is enriched for newly replicated DNA. Equal amounts of pulse label are incorporated into each of the strands of Col E1 supercoils isolated after a short pulse, indicating a symmetrical replication mechanism. The replication time of the Co1E1 plasmid is about 2 min at 33°C. The synthesis of Co1E1 supercoils was reduced to less than 10% of the control level 4 min after shift to 42 °C in a temperature‐sensitive mutant for DNA polymerase I.