The expression of recombinant genes from bacteriophage lambda strong promoters triggers the SOS response inEscherichia coli

Abstract

The production of several non‐related heterologous proteins in recombinant Escherichia coli cells promotes a significant transcription of recA and sfiA SOS DNA repair genes. The activation of the SOS system occurs when the expression of plasmid‐encoded genes is directed by the strong lambda lytic promoters, but not by IPTG‐controlled promoters either at 37 or at 42°C, and it is linked to an extensive degradation of the proteins after their synthesis. The triggering signal for the SOS response could be an important arrest of cell DNA replication observed within the first hour after the induction of recombinant gene expression. The stimulation of this DNA repair system can partially account for the toxicity exhibited by recombinant proteins on actively producing E. coli cells. © 1998 John Wiley & Sons, Inc. Biotechnol Bioeng 60: 551–559, 1998.

Efficient plasmid transfer via natural competence in a microbial co‐culture

“…Plasmid pBB275 consists of heterologous DNA sequences including sequences homologous to B. subtilis and a phage‐derived replication origin (f1 ori), which could activate the SOS response in E. coli (Arís et al , 1998; Lee et al , 2002; Johnson et al , 2019; Appendix Fig S4A). To evaluate the effect of the pBB275 plasmid on the activity of the SOS response, we characterized the SOS response in E. coli MG1655 harboring pBB275 and in E. coli MG1655 with a plasmid pUC19 that lacks the sequences homologous to ycgO in B. subtilis and the f1 ori (Appendix Fig S4B).…”

“…To our knowledge, the role of RecA in enhancing eDNA release and HGT efficiency in microbial communities has not been explored. Future studies can examine how different plasmid features could induce strong SOS response and plasmid multimerization (Arís et al , 1998; Lee et al , 2002; Johnson et al , 2019). For example, it is unknown whether the phage replication origin induces strong SOS response via forming single‐stranded DNA and thus triggers the SOS response (Johnson et al , 2019).…”