Extensive hydrolysis of raw rice starch by a chimeric α-amylase engineered with α-amylase (AmyP) and a starch-binding domain from Cryptococcus sp S-2
Extensive hydrolysis of raw rice starch by a chimeric α-amylase engineered with α-amylase (AmyP) and a starch-binding domain from Cryptococcus sp S-2
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DOI：
10.1007/s00253-017-8638-1
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发表时间：
2018-01-01
影响因子：
5
通讯作者：
Gao, Yi
中科院分区：
文献类型：
--
作者：
Peng, Hui;Li, Rui;Gao, Yi
重组嵌合α-淀粉酶(AmyP-Cr)由来自海洋宏基因组文库的α-淀粉酶(AmyP)的催化核心和来自隐球菌属的α-淀粉酶的淀粉结合域(SDCr)构建。 S-2。分子融合没有改变最适pH、最适温度、水解产物以及优先快速降解大米淀粉的能力，但催化效率和热稳定性较野生型AmyP显着提高。在 40 A 摄氏度下，每毫克生淀粉 1.0 U 条件下 4 小时后，AmyP-Cr 的最终水解度为 10% 生米淀粉 61.7 +/- 1.2%，15% 生米淀粉 47.3 +/- 0.8%。催化效率非常高，比AmyP高3.6-4.0倍。催化效率的提高归因于 SBDCr 更好的热稳定性以及对生米淀粉更高的吸附和破坏。 AmyP-Cr 的特性为生米淀粉加工的新设计开辟了新途径。
Recombinant chimeric alpha-amylase (AmyP-Cr) was constructed by a catalytic core of alpha-amylase (AmyP) from a marine metagenomic library and a starch-binding domain (SBDCr) of alpha-amylase from Cryptococcus sp. S-2. The molecular fusion did not alter optimum pH, optimum temperature, hydrolysis products, and an ability of preferential and rapid degradation towards raw rice starch, but catalytic efficiency and thermostability were remarkably improved compared with those of the wild-type AmyP. AmyP-Cr achieved the final hydrolysis degree of 61.7 +/- 1.2% for 10% raw rice starch and 47.3 +/- 0.8% for 15% raw rice starch after 4 h at 40 A degrees C with 1.0 U per mg of raw starch. The catalytic efficiency was very high, with 3.6-4.0 times higher than that of AmyP. The enhanced catalytic efficiency was attributed to the better thermostability and the higher adsorption and disruption to raw rice starch caused by SBDCr. The properties of AmyP-Cr open a new way in terms of a new design of raw rice starch processing.