Han Yujuan, Gao Peixin, Yu Wengong, Lu Xinzhi
Key Laboratory of Glycoscience & Glycotechnology of Shandong Province; Key Laboratory of Marine Drugs, Chinese Ministry of Education; Laboratory for Marine Drugs and Bioproducts, Qingdao National Laboratory for Marine Science and Technology; School of Medicine and Pharmacy, Ocean University of China, 5 Yushan Road, Qingdao, 266003, China.
Department of Glycobiology, School of Medicine and Pharmacy, Ocean University of China, 5 Yushan Road, Qingdao, 266003, China.
Biotechnol Lett. 2017 Dec;39(12):1895-1901. doi: 10.1007/s10529-017-2406-2. Epub 2017 Jul 26.
To determine the effects of carbohydrate-binding modules (CBMs) on the thermostability and catalytic efficiency of chitosanase CsnA.
Three CBMs (BgCBM5, PfCBM32-2 and AoCBM35) were engineered at the C-terminus of chitosanase CsnA to create hybrid enzymes CsnA-CBM5, CsnA-CBM32 and CsnA-CBM35. K values of all the hybrid enzymes were lower than that of the wild type (WT) enzyme; however, only CsnA-CBM5 had an elevated specific activity and catalytic efficiency. The fusion of BgCBM5 enhanced the thermostability of the enzyme, which exhibited a 8.9 °C higher T and a 2.9 °C higher T than the WT. Secondary structural analysis indicated that appending BgCBM5 at the C-terminus considerably changed the secondary structure content.
The fusion of BgCBM5 improved the thermal stability of CsnA, and the obtained hybrid enzyme (CsnA-CBM5) is a useful candidate for industrial application.
确定碳水化合物结合模块（CBMs）对壳聚糖酶CsnA热稳定性和催化效率的影响。
在壳聚糖酶CsnA的C末端设计了三个CBMs（BgCBM5、PfCBM32-2和AoCBM35），以创建杂合酶CsnA-CBM5、CsnA-CBM32和CsnA-CBM35。所有杂合酶的K值均低于野生型（WT）酶；然而，只有CsnA-CBM5具有提高的比活性和催化效率。BgCBM5的融合增强了酶的热稳定性，其T比WT高8.9°C，T比WT高2.9°C。二级结构分析表明，在C末端附加BgCBM5显著改变了二级结构含量。
BgCBM5的融合提高了CsnA的热稳定性，所得杂合酶（CsnA-CBM5）是工业应用的有用候选物。
