Difference between revisions of "Part:BBa K2817012"

Revision as of 16:02, 16 October 2018

PcspA-RBS-amilCP

CspA is a cold shock promoter and amilCP is a reporter.

Usage and Biology

We inserted this part into pColdI. Then we transformed the plasmid into DH5α and cultured overnight at 37℃. The overnight culture was diluted to OD = 0.2 and allowed to grow for 2 h at 37℃. It was then divided into different concentrations of IPTG at 16℃ and 37℃ for 6 h (Figure 1). It can be seen from the figure 1 that the reporter gene is efficiently expressed at low temperature, which indicates that the effective expression of the toxin gene mazF and the closed expression of the anti-toxin gene mazE at low temperature can kill our engineered bacteria in time. Although the cold shock promoter PcspA has a certain leakage at body temperature, the toxin is neutralized by the anti-toxin expressed at body temperature, so the effect is not significant. However, it is best to add a lacO site in the future to suppress leakage.

Figure 1. Pellets of bacteria transformed with constructed PcspA-amilCP plasmid after induction of 6h. From left to right: 37℃ without IPTG, 37℃ with 0.5mM IPTG, 37℃ with 1mM IPTG, 16℃ without IPTG, 16℃ with 0.5mM IPTG, 16℃ with 1mM IPTG.

[1] Stirling F, Bitzan L, O'Keefe S, et al. Rational Design of Evolutionarily Stable Microbial Kill Switches[J]. Molecular Cell, 2017, 68(4):686-697.

Sequence and Features