抄録
An F- strain of E. coli K 12 is unable to transfer its colicinogenic factor unless it has been transformed into F+. However, an F- col+ can transmit its colicinogenic factor to F- col- when R factor (multiple resistance factor from Shigella flexneri 2b) is introduced into the F- col+ cell. The frequency of co-transfer of the R factor and the colicinogenic factor is lower than that of F and the colicinogenic factors. The R factor produces “R substance” on the surface of a cell and the substance is inactivated by the treatment with sodium periodate. The production of male substance is suppressed when the R factor is introduced into F+ cell.
