Identification of Functional Toxin/Immunity Genes Linked to Contact-Dependent Growth Inhibition (CDI) and Rearrangement Hotspot (Rhs) Systems
Figure 5
CdiA-CTo1EC93 inhibits the growth of E. coli cells.
A) Growth curves of E. coli ΔsspB cells expressing CdiA-CTo1EC93/CdiIo1EC93-DAS. Degradation of CdiIo1EC93-DAS was initiated by the addition of L-arabinose to induce SspB synthesis. Control cells express SspB(Δ47), which does not deliver CdiIo1EC93-DAS to the ClpXP protease. Growth curves with square symbols represent control strains expressing SspB or SspB(Δ47), but not CdiA-CTo1EC93/CdiIo1EC93-DAS. B) Analysis of in vivo CdiA-CTo1EC93 tRNase activity. Total RNA was isolated from cells expressing CdiA-CTo1EC93/CdiIo1EC93-DAS at varying times after L-arabinose induction. Samples were run on polyacrylamide gels followed by staining with ethidium bromide (EtBr) or Northern blot analysis using probes specific for tRNA1BAla and tRNAHis.