在Halohydrin脱基酶HheC中的保存序列动因1残留的工程同时增强活性,稳定性和酶选择性
Sophie Staar1, Miquel Estévez-Gay2, Felix Kaspar1,3
1Institute for Biochemistry, Biotechnology and Bioinformatics, Technische Universität Braunschweig, Spielmannstr. 7, Braunschweig 38106, Germany.
ACS catalysis
|April 10, 2025
概括
转基因在氨酸脱酶 (HHDHs) 模式1中的保存残留物显著改变了酶活性,稳定性和选择性. 这项研究增强了对HHDH活性位点的理解,用于未来的酶工程.
科学领域:
- 酶工程是什么? 酶工程是什么?
- 生物催化剂是一种生物催化剂.
- 蛋白质科学 蛋白质科学
背景情况:
- 氨酸脱酶 (HHDHs) 是不对称合成的关键生物催化剂.
- HHDHs具有两个保存的序列动图,动图1可能会影响酶功能.
- 关于1号动机在HHDH活动,稳定性和选择性中的作用的实验数据有限.
研究的目的:
- 系统地研究突变在保存的动机1残留物对HHDH属性的影响.
- 探索1号动机结构与HHDH活性,稳定性和酶选择性之间的关系.
- 为HHDHs的理性工程提供见解.
主要方法:
- 在HheC和HheG的第1动机中保存的残留物的位点定向突变发生.
- 酶活性,稳定性 (热) 和酶选择性测定.
- 量子力学 (QM) 和分子动力学 (MD) 模拟.
主要成果:
- 基因1的氨酸和甘氨酸的突变只能被结构相似的氨基酸容忍.
- 图形1中的中央芳香残留物显示出更高的可变性,其中的变体表现出改变的酶特性.
- 变种HheC F12Y显示活性增加 (高达5倍),增强的酶选择性 (E=74与E=22) 和改善的稳定性 (10K高于Tm).
结论:
- 保存的1型残留物的向性突变发生可以显著改变HHDH酶特性.
- 动因1在HHDH核结合,活性,可溶性和稳定性方面发挥着关键作用.
- 这些发现促进了对HHDH活性位点的理解,并促进了未来的酶工程工作.
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