A highly Conserved Aspartic Acid Residue of the Chitosanase from Bacillus Sp. TS Is Involved in the Substrate Binding

详细信息    查看全文

• 作者：Zhanping Zhou ; Shuangzhi Zhao ; Yang Liu…
• 关键词：Chitosanase ; Glycoside hydrolase family 8 ; Aspartic acid ; Enzyme ; substrate interaction
• 刊名：Applied Biochemistry and Biotechnology
• 出版年：2016
• 出版时间：November 2016
• 年：2016
• 卷：180
• 期：6
• 页码：1167-1179
• 全文大小：2,126 KB
• 刊物类别：Chemistry and Materials Science
• 刊物主题：Chemistry
  Biotechnology
  Biochemistry
  
• 出版者：Humana Press Inc.
• ISSN：1559-0291
• 卷排序：180

文摘

The chitosanase from Bacillus sp. TS (CsnTS) is an enzyme belonging to the glycoside hydrolase family 8. The sequence of CsnTS shares 98 % identity with the chitosanase from Bacillus sp. K17. Crystallography analysis and site-direct mutagenesis of the chitosanase from Bacillus sp. K17 identified the important residues involved in the catalytic interaction and substrate binding. However, despite progress in understanding the catalytic mechanism of the chitosanase from the family GH8, the functional roles of some residues that are highly conserved throughout this family have not been fully elucidated. This study focused on one of these residues, i.e., the aspartic acid residue at position 318. We found that apart from asparagine, mutation of Asp318 resulted in significant loss of enzyme activity. In-depth investigations showed that mutation of this residue not only impaired enzymatic activity but also affected substrate binding. Taken together, our results showed that Asp318 plays an important role in CsnTS activity.