Figure 3.

(A) Effect of PSK on the transfer and transmission of incoming plasmids. (B) Effect of recipient cell immunity to PSK action on competitive exclusion. Transconjugant number was measured immediately after conjugation and after 10 generations of nonselective growth in LBH broth with vigorous shaking to give initial transfer frequency and final transmission frequency, respectively (as described in Materials and Methods). Transmission efficiency is the ratio of observed transmission to that expected if the resident plasmid had no effect on incoming plasmid stability. Values reported are the average (and SD) of at least four independent experiments.