| 초록 |
Violacein which has potent antibiotic properties is produced by expressing five genes from tryptophan, so we thought that changes in the production of tryptophan would affect the production of violacein. In this study, we applied the adaptive laboratory evolution (ALE) strategy to improve violacein production. A tryptophan-responsive biosensor was employed to enrich high-tryptophan-producing cells during the ALE. After six rounds of evolution, we transformed plasmids for violacein production into evolved cells and screened colonies showing the darkest purple. Consequently, we obtained the best violacein producer, which showed a 2.7-fold higher titer compared to the parental strain. Also, we identified several mutations via whole-genome sequencing of evolved strain, and we revealed that a missense mutation occurred on galR encoding galactose repressor. In conclusion, we showed that the biosensor-assisted ALE strategy could be useful to rapidly and selectively evolve strains. |
