Assessment of artificial operon in Bacillus subtilis to control transcription
2016
Majidian, Parastou | Najafi Zarrini, Hamid | Youshida, Ken | Ranjbar, Gholam Ali | Nemat Zadeh, Qorban Ali
In this study, we proposed the artificial operon which is capable of reversible transcriptional regulation control in Bacillus subtilis. Firstly, the creup and credown were mutated to release from CCR phenomenon. Then, the structural genes of gnt operon were placed under the control of constitutively strong promoter to degrade gluconate constitutively. In addition, the reporter gene (lacZ) was introduced under control of gnt promoters to evaluate functionality of the artificial operon. The results of pulse induction system showed no enzyme activity of each strain in the absence of inducer. By addition of 1 mM gluconate, the highest enzyme activity was shown at 1h after addition of inducer, and then the inducer degraded to turn off the operon. The maximum activation of enzyme was observed in 2h and 4h after addition of 2.5 and 5 mM gluconate into culture media, respectively. Our data indicated that the longer degradation of inducer and higher enzyme activity was appeared by more concentration of gluconate as well as growth arrest. It is suggested to use the pulse induction system and reversible artificial operon to achieve huge amount of special metabolite at short period of bacterial growth.
显示更多 [+] 显示较少 [-]