AUTHOR=Chen Hao , Wu Jie , Huang Xiaodan , Feng Xuzhong , Ji Hongwu , Zhao Liangzhong , Wang Jianrong 

TITLE=Overexpression of Bacillus circulans alkaline protease in Bacillus subtilis and its potential application for recovery of protein from soybean dregs

JOURNAL=Frontiers in Microbiology

VOLUME=13

YEAR=2022

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2022.968439

DOI=10.3389/fmicb.2022.968439

ISSN=1664-302X

ABSTRACT=<p>Proteases are important for decomposition of proteins to generate peptides or amino acids and have a broad range of applications in different industries. Herein, a gene encoding an alkaline protease (AprBcp) from <italic>Bacillus circulans</italic> R1 was cloned and bioinformatics analyzed. In addition, a series of strategies were applied to achieve high-level expression of AprBcp in <italic>Bacillus subtilis</italic>. The maximum activity of AprBcp reached 165,870 U/ml after 60 h fed-batch cultivation in 50 l bioreactor. The purified recombinant AprBcp exhibited maximum activity at 60°C and pH 10.0, and remained stable in the range from pH 8.0 to 11.0 and 30 to 45°C. Metal ions Ca<sup>2+</sup>, Mn<sup>2+</sup>, and Mg<sup>2+</sup> could improve the stability of AprBcp. Furthermore, the recombinant AprBcp displayed great potential application on the recovery of protein from soybean dregs. The results of this study will provide an effective method to prepare AprBcp in <italic>B. subtilis</italic> and its potential application on utilization of soybean dregs.</p>