Strategy to Obtain High Yield of Aminopeptidase from Recombinant Bacillus subtilis and Its Extraction Process Optimization

Abstract:

This study aimed to investigate the effects of different enzyme accelerants on the production of aminopeptidase by recombinant Bacillus subtilis and develop an efficient extract process of aminopeptidase. The results indicated that the enzyme accelerants（KCl at 0.1 mol/L，Tween-80 at 2.4 μL/mL，L-glutamate at 0.6%，potassium tartrate at 0.7%） significantly increased the production of aminopeptidase. The cultural conditions were of 60 mL/250 mL of liquid，5% inoculation size，at 37 ℃，initial pH 7.5，shake flask rotation 220 r/min，and cultured time 36 h. Under these conditions，the aminopeptidase activity of recombinant Bacillus subtilis could reach 232.5 U/mL. Using the efficient extract process of aminopeptidase，the recovery and the purification fold of the L-leucine aminopeptidase could reach 67.23% and 8.29，respectively.