Swapping the chitin-binding domain in Bacillus chitinases improves the substrate binding affinity and conformational stability
Swapping the chitin-binding domain in Bacillus chitinases improves the substrate binding affinity and conformational stability
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DOI：
10.1039/b923048c
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发表时间：
2010-01-01
影响因子：
--
通讯作者：
Podile, Appa Rao
中科院分区：
文献类型：
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作者：
Neeraja, Chilukoti;Subramanyam, Rajagopal;Podile, Appa Rao
苏云金芽孢杆菌和地衣芽孢杆菌的几丁质酶由N端催化结构域(GH18)和C端几丁质结合结构域(ChBD)组成。为了研究单个结构域的重要性，以结构域交换为策略构建了嵌合几丁质酶(BtGH-BliChBD和Bligh-BtChBD)，以实现BtGH-ChBD和Bligh-ChBD的CBD互换。两种嵌合几丁质酶均表现出对胶体几丁质亲和力增强。BtGH-BliChBD在最适温度和最适pH方面与所研究的其他三种几丁质酶不同。此外，与天然几丁质酶相比，BtGH-BliChBD和Bligh-BtChBD在功能稳定性、构象稳定性以及与不溶性几丁质底物的结合能力方面都有显著提高。
Chitinase from Bacillus thuringiensis and Bacillus licheniformis consisting of an N-terminal catalytic domain (GH18) and a C-terminal chitin-binding domain (ChBD), were cloned and characterised. In order to study the importance of individual domains, chimeric chitinases (BtGH-BliChBD and BliGH-BtChBD) were constructed using domain swapping as a strategy to exchange the CBD of BtGH-ChBD with that of BliGH-ChBD and vice versa. Both chimeric chitinases showed increased affinity to colloidal chitin. BtGH-BliChBD was different from the three other chitinases studied concerning optimum temperature and pH. Additionally, BtGH-BliChBD and BliGH-BtChBD showed significant improvement in functional stability, conformational stability, and binding ability towards insoluble chitinous substrates compared to those of the native chitinases.