Heterogeneous expression, molecular modification of amylosucrase from Neisseria polysaccharea, and its application in the preparation of turanose.
Heterogeneous expression, molecular modification of amylosucrase from Neisseria polysaccharea, and its application in the preparation of turanose.
复制标题
DOI：
10.1016/j.foodchem.2020.126212
复制
发表时间：
2020-01
期刊：
影响因子：
8.8
通讯作者：
Lingqia Su;Yaqi Zhao;Dan Wu;Jing Wu
中科院分区：
文献类型：
--
作者：
Lingqia Su;Yaqi Zhao;Dan Wu;Jing Wu
松二糖是一种新型的食品甜味剂，利用多糖奈瑟氏菌淀粉蔗糖酶（NpAS）可以合成松二糖，但副产物麦芽低聚糖影响了松二糖的得率。在本研究中，获得了NpAS突变体G396 S，其预期通过增加空间位阻来干扰葡聚糖的延伸。在枯草杆菌中异源表达NpAS和G396 S，并分析其酶性质。结果表明，G396 S的聚合活性降低。此外，该突变株还用于松二糖的制备。当以2 M蔗糖为底物时，松二糖产量达到410.4g·L-1，比NpAS提高了61 g·L-1。当添加果糖时，G396 S的最佳果糖浓度从0.75 M降低到0.5 M。松二糖产量为523 g·L-1，转化率为76.5%。本研究有助于松二糖在食品工业中的应用。
Turanose, a potential novel sweetener in food industry, can be synthesized byNeisseria polysacchareaamylosucrase (NpAS).However, the malt-oligosaccharide byproduct affects the yield. In this study, the NpAS mutant G396S, which was expected to interfer with the extension of glucan by increasing steric hindrance, was obtained. The NpAS and G396S were heterologously expressed inBacillus subtilisand enzyme properties were analyzed. Results showed that the polymerization activity of G396S was decreased. In addition, the mutant was used in the preparation of turanose. When using 2 M sucrose as substrate, the turanose yield reached 410.4 g·L−1, an increase of 61 g·L−1compared with that of NpAS. When fructose was added, the optimal fructose concentration for G396S decreased from 0.75 M to 0.5 M. The turanose production reached 523 g·L−1with the conversion rate of 76.5%. This study contributes the use of turanose in food industry.