Addition of Co2+ to culture medium decides the functional expression of a recombinant nitrile hydratase in Escherichia coli

作者：Pei, Xiaolin^*; Wang, Qiuyan; Li, Chenglu; Yin, Xiaopu; Chen, Rong; Xie, Tian

来源：Biotechnology Letters, 2013, 35(9): 1419-1424.

DOI：10.1007/s10529-013-1215-5

• Cobalt ions
• beta-Mercaptoethanol
• Nitrile hydratase
• Recombinant expression
• Regeneration

A nitrile hydratase (NHase) gene from Aurantimonas manganoxydans, cloned and expressed in Escherichia coli, gave an enzyme that efficiently hydrated 3-cyanopyridine to nicotinamide with high thermal stability. We have now found that adding Co2+ at 0.1 mM to LB medium was essential for production of an active enzyme. However, a parts per thousand yen0.3 mM Co2+ inhibited the growth of host cells in LB medium and decreased the production of the recombinant NHase. Furthermore, beta-mercaptoethanol promoted regeneration of the Co2+-defective apoenzyme in vitro possibly by breaking a key disulfide bond thereby promoting the incorporation of Co2+ into the apoenzyme.

• 出版日期2013-9
• 单位杭州师范大学