文献类型：期刊文献

英文题名：Enhanced Thermostability of Geobacillus stearothermophilus α-Amylase by Rational Design of Disulfide Bond and Application in Corn Starch Liquefaction and Bread Quality Improvement

作者：Zhu, Mengyu[1];Zhai, Wenxin[1];Song, Runfei[1];Lin, Lin[2,3];Wei, Wei[1];Wei, Dongzhi[1]

机构：[1]East China Univ Sci & Technol, Newworld Inst Biotechnol, State Key Lab Bioreactor Engn, Shanghai 200237, Peoples R China;[2]Shanghai Inst Technol, Sch Chem & Environm Engn, Shanghai 201418, Peoples R China;[3]Natl Engn Res Ctr Nanotechnol, Res Lab Funct Nanomat, Shanghai 200241, Peoples R China

年份：2023

卷号：71

期号：48

起止页码：18928

外文期刊名：JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY

收录：;EI(收录号：20234915173492);WOS:【SCI-EXPANDED(收录号:WOS:001115549600001)】；

基金：This work was supported by the grant from the National Key Research and Development Program of China (2021YFC2100300), the Shanghai Natural Science Foundation (no. 20ZR1415400), the Shanghai Institute of Technology's Collaborative Innovation Foundation (10120K228051), and the Shanghai Institute of Technology's scientific research start funds (10120K226107).

语种：英文

外文关键词：alpha-amylase; disulfide bond; thermostability; force network; corn starch liquefaction; breadaging

摘要：alpha-Amylase (EC 3.2.1.1) from Geobacillus stearothermophilus (generally recognized as safe) exhibited thermal inactivation, hampering its further application in starch-based industries. To address this, we performed structural analyses based on molecular dynamics targeting the flexible regions of alpha-amylase. Subsequently, we rationally designed a thermostable mutant, AmyS1, by introducing disulfide bonds to stabilize the flexible regions. AmyS1 showed excellent thermostability without any stability-activity trade-off, giving a 40-fold longer T-1/2 (1359 min) at 90 degrees C. Thermostability mechanism analysis revealed that the introduction of disulfide bonds in AmyS1 refined weak spots and reconfigured the protein's force network. Moreover, AmyS1 exhibited improved pH compatibility and enhanced corn starch liquefaction at 100 degrees C with a 5.1-fold increased product concentration. Baking tests confirmed that AmyS1 enhanced bread quality and extended the shelf life. Therefore, mutant AmyS1 is a robust candidate for the starch-based industry.