Development of a conditional lethal system for a Streptomyces lividans strain and its use to investigate conjugative transfer in soil

In Streptomyces lividans, a conditional lethal mechanism was obtained by inactivation of gylB in the glycerol operon. The resulting strain was efficiently counter-selected on glycerol-containing medium but the mutation had no effect on the capacity of the strain to be maintained in non-sterile soil samples and to transfer derivatives of the genetic element pSAM2. However, despite the efficiency of the donor counter-selection system, the transfer of a pSAM2 derivative from S. lividans to indigenous soil bacteria was not detected.