Construction of a chassis cell with conditional suicide from Pseudomonas putida F1

Abstract:

[Background] Pseudomonas putidaF1 with simple nutritional requirements, rapid growth, and diverse metabolic pathways is regarded as one of the most promising chassis cells in synthetic biology. However, few studies have reported the application of P. putida F1 as a biodegradable chassis cell by streamlining the genome. [Objective] To construct a chassis cell with high biosafety. [Methods] We employed scarless genome editing based on homologous recombination principle to streamline the genome of P. putida F1 and integrated the conditional suicide system into the genome. [Results] Two lysogenic phage genomic islands PP1 (50.7 kb) and PP2 (58.4 kb), which account for 1.83% of the genome size, were successfully knocked out, and a knockout strain P. putida F1ΔPP12 was constructed. Furthermore, the conditional suicide system controlled by the arabinose promoter was integrated into the site of upp in the genome of P. putida F1ΔPP12, and thus a chassis cell P.putida F1ΔPP12-P_ara-nuc with high biosafety was successfully constructed. [Conclusion] This study increases the application value of P.putida F1 and provides a theoretical basis for the application of this strain or genetically engineered bacteria from this strain in environment remediation in situ.