Bhatia Shashi Kant, Kim Yong Hyun, Kim Hyun Joong, Seo Hyung-Min, Kim Jung-Ho, Song Hun-Seok, Sathiyanarayanan Ganesan, Park Sung-Hee, Park Kyungmoon, Yang Yung-Hun
Department of Biological Engineering, College of Engineering, Konkuk University, Seoul, 143-701, Republic of Korea.
Food Ingredients Center, Foods R&D, CheilJedang, Guro-dong, Guro-Gu, Seoul, 152-051, Republic of Korea.
Bioprocess Biosyst Eng. 2015 Dec;38(12):2315-22. doi: 10.1007/s00449-015-1465-9. Epub 2015 Aug 28.
In this study, Escherichia coli cells overexpressing lysine decarboxylase (CadA) were used for cadaverine production. Barium alginate was selected as a matrix for immobilization of E. coli YH91. Free cells and immobilized cells (IC) were characterized for their physiochemical properties, and the optimum pH and temperature were determined as 6 and 37 °C, respectively. Immobilized cells were three times more thermally stable compared to free cells at the optimum temperature and had a half-life (t 1/2) of 131 h. The free cells lost most of lysine decarboxylase activity after nine cycles, but in contrast immobilized cells retained 56% of their residual activity even after the 18th cycle. The immobilized cells gave a maximum production of cadaverine (75.8 g/L) with 84% conversion.
在本研究中，使用过表达赖氨酸脱羧酶（CadA）的大肠杆菌细胞来生产尸胺。选择海藻酸钡作为固定化大肠杆菌YH91的基质。对游离细胞和固定化细胞（IC）的理化性质进行了表征，确定最佳pH值和温度分别为6和37℃。在最佳温度下，固定化细胞的热稳定性是游离细胞的三倍，半衰期（t 1/2）为131小时。游离细胞在九个循环后失去了大部分赖氨酸脱羧酶活性，但相比之下，固定化细胞即使在第18个循环后仍保留其残余活性的56%。固定化细胞产生的尸胺产量最高（75.8 g/L），转化率为84%。
