Biochemical Characterization of An Arginine-Specific Alkaline Trypsin from Bacillus licheniformis

International Journal of Molecular Sciences

Jin-Song Gong¹  Wei Li¹  Dan-Dan Zhang²  Min-Feng Xie²  Biao Yang²  Rong-Xian Zhang²  Heng Li²  Zhen-Ming Lu²  Zheng-Hong Xu²  Jin-Song Shi¹ 

[1] School of Pharmaceutical Science, Jiangnan University, Wuxi 214122, China

关键词: trypsin;    Bacillus licheniformis;    enzymatic properties;    cloning;    biocatalysis;   

DOI  :  10.3390/ijms161226200

来源: mdpi

【 摘 要 】

In the present study, we isolated a trypsin-producing strain DMN6 from the leather waste and identified it as Bacillus licheniformis through a two-step screening strategy. The trypsin activity was increased up to 140 from 20 U/mL through culture optimization. The enzyme was purified to electrophoretic homogeneity with a molecular mass of 44 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and the specific activity of purified enzyme is 350 U/mg with Nα-Benzoyl-l-arginine ethylester as the substrate. The optimum temperature and pH for the trypsin are 65 °C and pH 9.0, respectively. Also, the enzyme can be significantly activated by Ba²⁺. This enzyme is relatively stable in alkaline environment and displays excellent activity at low temperatures. It could retain over 95% of enzyme activity after 180 min of incubation at 45 °C. The distinguished activity under low temperature and prominent stability enhance its catalytic potential. In the current work, the open reading frame was obtained with a length of 1371 nucleotides that encoded a protein of 456 amino acids. These data would warrant the B. licheniformis trypsin as a promising candidate for catalytic application in collagen preparation and leather bating through further protein engineering.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.