在尼辛脱水酶 (NisB) 的催化过程中,领头结合的特征
Lindsay M Repka1, Kenton J Hetrick1, See Hyun Chee1
1Department of Chemistry and Howard Hughes Medical Institute, University of Illinois, Urbana-Champaign , 600 South Mathews Avenue , Urbana , Illinois 61801 , United States.
Journal of the American Chemical Society
|March 15, 2018
概括
尼斯B脱水酶对抗菌尼素进行修改. 研究人员证实,NisB在尼生物合成过程中使用单个结合点.
科学领域:
- 生物化学
- 分子生物学
- 酵素学
背景情况:
- 尼生物合成涉及脱水酶NisB,它修改了NisA前体.
- NisA有一个C端核心和一个N端领导 (LP),对脱水至关重要.
- 在NisB中介脱水中LP的确切作用尚不清楚.
研究的目的:
- 阐明NisA领导 (LP) 和NisB脱水酶之间的相互作用机制.
- 确定NisB是否使用单一的结合点来进行谷氨基化和谷氨基酸消除.
主要方法:
- 设计了一种二硫化键,以共价地将Nisa LP与NisB连接起来.
- 评估了绑定的Nisa-NisB复合物的脱水酶活性.
- 研究了NisA和tRNAGlu与NisB的结合顺序.
主要成果:
- 设计的二硫化物键成功地将NisA LP与NisB结合起来.
- 该酶完全脱水了绑定的Nisa,证实了功能性LP结合部位.
- 确定了与NisB结合的NisA和tRNAGlu的顺序,从而促进脱水.
结论:
- 尼斯B对尼斯ALP采用单一的结合位点,可以同时进行谷氨基化和谷氨基酸消除.
- 这些发现支持由NisB介导的尼脱水的顺序机制.
- 了解LP-NisB相互作用提供了对翻译后修改机制的见解.
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