Optimization of Trehalose Synthase Fermentation Conditions from Recombinant Escherichia coli

Abstract:

In order to achieve efficient production of the trehalose synthase from Thermus thermophilus，the optimization of fermentation conditions was investigated in E.coli BL21（DE3） harboring the plasmid pET24a（+）-TreS. The optimized fermentation conditions were as follows：the inducing temperature is 32 ℃，the adding rate of lactose is 0.2 g/（L·h） When OD600 reached 50. Under the condition，the enzyme activity reached 472 U/mL at cultivation of 35 h，was 2.3 times than before. In addition，the fermentation was performed in 30 L bioreactor under the condition of preceding narrative，the enzyme activity reached 356 U/mL. Because the thermal stability of trehalose synthase is good， E.coli cell was broken up through high temperature. The results showed that treated it 30 min under 80 ℃ the yield of trehalose synthase reached 72.3％. It have industrial application prospect.