Pascal Schönberg

• The aim of this bachelor thesis was to establish extracytoplasmic function (ECF) σ factors as synthetic genetic regulators for biotechnological and synthetic biology applications in the new emerging model organism Vibrio natriegens. Therefore, synthetic genetic circuits were engineered on plasmids as test set-up for the investigated ECFs and their target promoters. The resulting plasmid library consisted of the reporter plasmids with the target promoter, fused to a lux cassette, a set of high-copy ECF plasmids and a backup set of lower-copy ECF plasmids. First, the high-copy plasmids were transformed in V. natriegens to test them for their functionality upon different inducer levels, which yielded good inducibility for few, but showed too high ECF-expression in most strains. For this reason, the set of lower copy plasmids was used for combinatorial co-transformation, to investigate the ECFs for their cross-talk to unspecific ECF target promoters. The switching to the lower-copy plasmid-set seemed to be partly helpful, while still much room for fine-tuning of the circuits remains. The knowledge gained can be used to achieve higher success rates when engineering synthetic circuits for various applications in V. natriegens, by using the ECFs here recommended as suitable synthetic genetic regulators.