期刊
JOURNAL OF STRUCTURAL BIOLOGY
卷 198, 期 3, 页码 154-162出版社
ACADEMIC PRESS INC ELSEVIER SCIENCE
DOI: 10.1016/j.jsb.2017.02.001
关键词
beta-Glycosidase; Glucose-tolerant; Thermostability; Crystal structure; Catalysis
资金
- Guangdong Innovative Research [2011Y038]
- Science and Technology Program of Guangzhou [201504010025]
- Fundamental Research Funds for the Central Universities [161gjc76]
Cellulose can be converted to ethanol via the fermentation of glucose, which is considered as a promising green alternative for transportation fuels. The conversion of cellulose to glucose needs three enzymes, in which B-glucosidase (BGL) plays an essential role. However, BGL is inhibited by its own product glucose, greatly limiting its applications in industry. We previously obtained a novel BGL named Bg16 with a high glucose tolerance. Further engineering through random mutagenesis produced a triple mutant M3 with improved thermostability. This enzyme shows promising properties for wide applications but the structural basis of the unusual properties of Bg16 is not clear. In this study, we determined the crystal structures of Bg16 and variants at high resolution, which provide insights into its glucose-tolerant mechanism and thermostability. Particularly, Bg16 forms an extra channel that could be used as a secondary binding site for glucose, which may contribute to glucose tolerance. Additionally, the triple mutations could strengthen the hydrophobic interactions within the enzyme and may be responsible for the enhanced thermostability exhibited by M3, which was further confirmed by dynamic light scattering data. Lastly, structural comparison to other orthologs allows us to formulate new strategies on how to improve the catalytic efficiency of Bg16. (C) 2017 Elsevier Inc. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据