FIG 2.

Relative conjugational transfer efficiencies of plasmid pLS20. The efficiencies were assessed in donor mutant strains and recipient mutant strains (gray) and compared to those of wild-type donors and wild-type recipients (black) from the same genetic background. To test for donor efficiency, the recipient strain was always kept the same and the genetic background of the donor strain varied. To test the ability to receive the plasmid from the wild-type strain, the donor strain was kept the same and the genetic background of the recipients varied. Each experiment was performed at least in triplicate, and the conjugation efficiency was calculated as the number of transconjugants (CFU) per number of donors (CFU). For comparing relative levels, the efficiency of wild-type donor or wild-type recipient cells were set to 100%. Error bars represent standard deviations. Statistical significances were computed using two-sided independent sample t test. P < 0.05 (*) and P < 0.001 (***) compared to the pLS20-free strain.