通过祖先II类酸酶CfbA识别四氧化基质的结构洞察力
Shoko Ogawa1, Masahide Hikita2, Takashi Fujishiro1
1Department of Biochemistry and Molecular Biology, Graduate School of Science and Engineering, Saitama University, Saitama, Japan.
Protein science : a publication of the Protein Society
|November 16, 2024
概括
祖先基酶CfbA通过不同的结合位点识别不同的四氧化. 突变显示,活性位子残留物Ser11的极性和水相互作用是酶酶中基质选择性的关键.
科学领域:
- 生物化学 生物化学
- 结构生物学 结构生物学
- 酶学 是一种酶学.
背景情况:
- 切拉酶CfbA是一种祖先II类酶,具有独特的对称活性位点.
- 它使用氨酸 (SHC) 进行辅酶F430生物合成.
- 祖先酸酶表现出广泛的四聚烯特异性,使它们的基质识别机制引起了人们的兴趣.
研究的目的:
- 为了研究祖先基酶CfbA的基底识别机制.
- 要确定CfbA如何区分不同的四氧化基质.
- 阐明活性部位残留在基质结合和选择性中的作用.
主要方法:
- 对CfbA复合的X射线晶体分析与尿素林III (UPIII) 和尿素林I (UPI).
- 活性部位残留物Ser11的局部导向突变发生.
- 野生类型和突变CfbA变体的酶活性测定.
- 基质-酶相互作用的计算建模.
主要成果:
- UPIII和UPPI结合在CfbA活跃区域内的不同位置:入口处的UPPI和UPIII深处的UPIII.
- 对于与UPIII和UPPI的极性相互作用,Ser11是至关重要的.
- 这种CfbA S11T变体与更疏水的甲基胺I (CPI) 具有活性.
- 在残留物11中平衡极性和疏水性相互作用会影响基质选择性.
结论:
- 在CfbA中,不同的四氧化具有不同的结合模式,通过主动站点架构进行介绍.
- 通过极性相互作用,Ser11在四氧化的识别中发挥着关键作用.
- 在残留物11的调节相互作用可以改变基质选择性,为酶进化提供了见解.
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