Transfer competence, a bistable process induced by integrative and conjugative elements in bacteria

We have been able to characterise the main promoters present on ICEclc, which become bistably expressed in the same cell. This has been established using single copy promoter fusions to egfp and mcherry, and in combination with FISH for mRNA, which permit to follow expression at the single level and allow co-expression studies. In addition, time - laps imaging was carried out to detect the possible timing of ICEclc bistable gene expression and relative firing of the different promoters. A new regulatory locus was discovered on ICEclc, which functions as a master regulator to the ICEclc activation process in stationary phase cells. Finally, we have been trying with some success to reproduce bistability by construction from individual gene blocks in a host devoid of ICEclc.