在胺 thiazole 生物合成中缺失的酶:确定 TenI 是一种 thiazole 复合酶
Amrita B Hazra1, Ying Han, Abhishek Chatterjee
1Department of Chemistry, Texas A&M University, College Station, Texas 77843, USA.
Journal of the American Chemical Society
|May 4, 2011
概括
以前功能不明的细菌酶TenI被确定为一种 thiazole tautomerase. 这一发现完成了主要细菌胺生物合成途径所需的酶组.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 酶学 是一种酶学.
背景情况:
- 酶TenI经常与细菌中胺 thiazole 生物合成的基因一起发现.
- 尽管其序列与胺酸盐合成酶相似,但TenI缺乏这种活性,因此其在胺生产中的作用尚不清楚.
研究的目的:
- 为了阐明细菌酶TENI的未知功能.
- 描述与胺生物合成有关的TenI的催化机制和结构.
主要方法:
- 酶净化和活性测定.
- 用X射线晶体学来确定酶-连接体复杂结构.
- 位点定向的突变发生,以确定催化残留物.
主要成果:
- 泰尼作为一种 thiazole 复合酶,而不是一种 thiamin 酸盐合成酶.
- 酶基质复合结构显示酸盐和胺122是关键的催化成分.
- 提出了一种涉及histidine 122作为酸催化剂的反应机制.
结论:
- 现在已经确定了TENI作为 thiazole tautomerase 的功能.
- 这一发现解决了细菌主要胺生物合成途径中所有酶的身份.
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