Expression of the kil gene of the ColE1 plasmid in Escherichia coli Kilr mutants causes release of periplasmic enzymes and of colicin without cell death.

Expression of the kil gene of the ColE1 plasmid in certain classes of Escherichia coli mutants (Kilr) resistant to kil-caused cell death brought about release of periplasmic enzymes and of colicin. Phospholipase A was present but was not activated by kil expression in any of the mutants. This indicates that in these mutants the various effects of kil gene expression have become dissociated.