HolSMP is toxic to E. coli and cyanide triggers the lethal potential of HolSMP. (A) The growth and viability assays of BL21(DE3)pLysS harboring plasmid pEXH1 were performed after addition of IPTG. At the time indicated by the arrow, KCN was added to the culture. Non-induced BL21(DE3)pLysS (pEXH1) was also monitored as control. (B) Western blotting was performed on total cellular protein of IPTG induced BL21(DE3)pLysS (pEXH1) to detect expression of HolSMP. Cultures of BL21(DE3)pLysS (pEX) were collected at 56 min after induction as a negative control (-). A size marker is shown in the last lane.