文献类型：期刊文献

英文题名：Characterization of a nitrilase from Arthrobacter aurescens CYC705 for synthesis of iminodiacetic acid

作者：Cai, Wenwen[1];Su, Erzheng[2];Zhu, Shujing[1];Ren, Yuhong[1];Wei, Dongzhi[1]

机构：[1]E China Univ Sci & Technol, New World Inst Biotechnol, State Key Lab Bioreactor Engn, Shanghai 200237, Peoples R China;[2]Nanjing Forestry Univ, Coll Light Ind Sci & Engn, Enzyme & Fermentat Technol Lab, Nanjing 210037, Jiangsu, Peoples R China

年份：2014

卷号：60

期号：6

起止页码：207

外文期刊名：JOURNAL OF GENERAL AND APPLIED MICROBIOLOGY

收录：;WOS:【SCI-EXPANDED(收录号:WOS:000348704300001)】；

基金：This work was supported by the National Basic Research Program of China (No. 2012CB721003), the Fundamental Research Funds for the Central Universities and the Open Funding Project of the State Key Laboratory of Bioreactor Engineering.

语种：英文

外文关键词：Arthrobacter aurescens; characterization; iminodiacetic acid; nitrilase

摘要：A nitrilase gene cyc705 from Arthrobacter aurescens CYC705 for synthesis of iminodiacetic acid (IDA) was cloned. This gene contained a 930 bp ORF, which encoded a polypeptide of 310 amino acids. A recombinant Escherichia coli BL21(DE3)/pET28a-cyc705 was constructed to achieve the heterologous expression of cyc705. This recombinant nitrilase was purified to homogeneity with a molecular weight of 36.7 kDa on SDS-PAGE and mass spectrometry, and characterized to be an oligomer of 14 subunits by gel permeation chromatography. Using iminodiacetonitrile (IDAN) as the substrate, the V-max, K-m, k(cat) and k(cat)/K-m were 9.05 U mg(-1), 43.17 mM(-1), 94.1 min(-1) and 2.18 x 10(3) min(-1) M-1, respectively. The optimum temperature and pH were 25 degrees C and 5.8. The suitable substrates for the purified nitrilase were short-chain aliphatic dinitriles. High concentration of IDAN could be hydrolyzed to IDA in a shorter time.