FIG. 5.

Stability of TraJ, TraM, and TraY expressed from a foreign promoter in cpxA101*. (A) Immunoblot analysis with polyclonal antiserum to detect TraJ expressed from the pBADTraJ overexpression vector. Lane 1, TraJ expressed from pOX38-Km in MC4100; lane 2, TraJ expressed from pBADTraJ under repressed conditions; lanes 3 to 7, TraJ expressed from pBADTraJ after induction by arabinose and subsequent inhibition of further rounds of transcription by the addition of glucose and rifampin. The number above each lane indicates the time (in minutes) at which each sample was taken after the addition of rifampin and glucose. The host strains tested are shown on the right, and the relevant molecular weight marker is shown (in kilodaltons) on the left. The loading control indicated at the bottom of the figure is obtained from a protein that nonspecifically cross-reacts with the antiserum. (B and C) Stability of TraM and TraY, respectively, expressed from the pBADTraM and pBADTraY overexpression vectors were examined as described in panel A.