文献类型：期刊文献

英文题名：N-Terminal Domain Truncation and Domain Insertion-Based Engineering of a Novel Thermostable Type I Pullulanase from Geobacillus thermocatenulatus

作者：Li, Lingmeng[1];Dong, Fengying[1];Lin, Lin[2,3];He, Dannong[3];Wei, Wei[1];Wei, Dongzhi[1]

机构：[1]East China Univ Sci & Technol, State Key Lab Bioreactor Engn, Newworld Inst Biotechnol, Shanghai 200237, Peoples R China;[2]Shanghai Univ Med & Hlth Sci, Shanghai 200093, Peoples R China;[3]Natl Engn Res Ctr Nanotechnol, Res Lab Funct Nanomat, Shanghai 200241, Peoples R China

年份：2018

卷号：66

期号：41

起止页码：10788

外文期刊名：JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY

收录：;EI(收录号：20183905860429);WOS:【SCI-EXPANDED(收录号:WOS:000447953900013)】；

基金：This research was financially supported by the National Natural Science Foundation of China (No. C31570795), the Shanghai International Science and Technology Cooperation Project (No. 14520720500), the Minhang District Leading Talent Project (No. 201541), and the Shanghai Talent Development Project (No. 201531).

语种：英文

外文关键词：Geobacillus thermocatenulatus; pullulanase; domain truncation and insertion; maize starch

摘要：A novel thermostable type I pullulanase gene (pul(GT)) from Geobacillus thermocatenulatus DSMZ730 was cloned. It has an open reading frame of 2154 bp encoding 718 amino acids. G. thermocatenulatus pullulanase (Pul(GT)) was found to be optimally active at pH 6.5 and 70 degrees C. It exhibited stable activity in the pH range of 5.5-7.0. Pul(GT) lacked three domains (CBM41 domain, X25 domain, and X45 domain) compared with the pullulanase from Bacillus acidopullulyticus (2WAN). Different N-terminally domain truncated (730T) or spliced (730T-U1 and 730T-U2) mutants were constructed. Truncating the N-terminal 85 amino acids decreased the K-m value and did not change its optimum pH, an advantageous biochemical property in some applications. Compared with 2WAN, Pul(GT) can be used directly for maize starch saccharification without adjusting the pH, which reduces cost and improves efficiency.