Transfer of a Colicinogenic Character by Protoplast of Escherichia coli K-12

Protoplasts of Escherichia coli K 12 have the ability to transfer their F and colicinogenic characters to recipient cells. These transfers are effectively performed when F+ col+ is used as the donor and F- col- as the recipient. Simultaneous transfer of both characters in high freuquency is observed. F- col+ protoplasts can not transfer their col+ to either F- col- or F+ col-. The transformed cells maintain the properties of the initially non-colicinogenic and F- strain except for the newly acquired col+, F+ or F+ col+ characteristics.