对两个细菌环氧化物酸盐的不同基质偏好进行结构洞察
Jisub Hwang1, Min Ju Lee2, Sung Gu Lee1
1Division of Life Sciences, Korea Polar Research Institute, Incheon 21990, Republic of Korea; Department of Polar Sciences, University of Science and Technology, Incheon 21990, Republic of Korea.
International journal of biological macromolecules
|February 29, 2024
概括
两个新特征的环氧化化酶 (EHs),BoEH和CaEH,显示出不同的基质特异性. 结构和计算分析确定了它们的基质结合位点的关键差异,解释了它们对阿利法,芳香和循环阿利法化合物的不同偏好.
科学领域:
- 生物化学 生化学
- 结构生物学 结构生物学
- 酶学 是一种酶学.
背景情况:
- 环氧化酶 (EHs) 是催化环氧化物转化为二醇的酶,在各种生物过程中至关重要.
- 由于其在合成有机化学应用中对抗原体纯二醇的有用性,EH越来越受认可.
研究的目的:
- 阐明两个不同的环氧化化酶,BoEH和CaEH的基质特异性的结构基础.
- 为了比较BoEH和CaEH的结构特征和催化机制.
主要方法:
- 采用X射线晶体学来确定BoEH和CaEH的高分辨率结构.
- 进行了酶活性测定,以评估基质偏好.
- 进行了计算对接模拟和道识别,以分析基质结合相互作用.
主要成果:
- 无论是BoEH还是CaEH,都表现出特有的α/β酶折叠,具有保存的催化残留物 (Asp-Asp-His) 和环开放残留物 (Tyr-Tyr).
- 在帽子域中观察到显著的序列变异,影响了基质结合部位.
- BoEH对线性合基板表现出更高的活性,而CaEH更喜欢芳香和环合基板.
- 计算分析突出了负责不同基质结合偏好的特定残留物.
结论:
- 结构上的差异,特别是盖域和基质结合位点残留的结构差异,与观察到的BoEH和CaEH的基质特异性密切相关.
- 这些发现提供了关于环氧化酶的结构功能关系及其在生物催化剂中定制应用的潜力有价值的见解.
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