DNA is essential for organisms survival; however, without protective mechanisms, it is highly susceptible to degradation by environmental factors. In response to unfavorable conditions, certain bacteria undergo sporulation to form spores that protect their genome from degradation. Recent studies have demonstrated that bacteriophages infecting spore-forming bacteria can modulate the host’s sporulation process and exploit it to facilitate the protection of their own genome. In this study, we investigated whether bacteriophage GIL01, infecting the spore-forming bacterium Bacillus thuringiensis serovar israelensis, influences the sporulation process of its host, and whether its linear genome is incorporated into spores alongside the host chromosome. No significant effect of GIL01 on the sporulation frequency of strains GBJ002 and T0131 was observed. Nonetheless, the GIL01 genome was detected in over 98 % of B. thuringiensis spores, supporting the hypothesis that certain phages can exploit host sporulation process as a strategy for survival under unfavorable environmental conditions. Insights into these natural DNA protection mechanisms can facilitate the development of synthetic platforms for DNA encapsulation. Accordingly, the second part of this study focused on the development of a programmable DNA encapsulation system in the non-sporulating bacterium Escherichia coli. The Pdu microcompartment, originally involved in 1,2-propanediol metabolism in Citrobacter freundii, was repurposed as a synthetic protein shell enabling encapsulation of a target linear DNA fragment. To facilitate this, the transcriptional repressor LacI was engineered to bind the target DNA and mediate its sequestration within the Pdu microcompartment. The modified microcompartments were subsequently purified from bacterial lysates via a Twin-Strep-tag by affinity chromatography. Sequencing of DNA isolated from affinity-purified microcompartments confirmed successful encapsulation of the target linear fragment carrying multiple LacI-binding sites. Moreover, the encapsulated DNA was protected from degradation by exogenously added nucleases, demonstrating that Pdu-derived microcompartments can serve as efficient protective carriers for nucleic acids.
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