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一种具有广泛基质范围的对抗选择性脂酶的定向进化,用于解α替代性
Karin Engström1, Jonas Nyhlén, Anders G Sandström
1Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, SE-106 91 Stockholm, Sweden.
Journal of the American Chemical Society
|May 11, 2010
概括
定向进化创造了一种Candida antarctica脂酶A (CalA) 变体,具有显著增强的活性和水解的广泛基质范围. 这种工程酶表现出反向的 (R) 选择性,提供了新的合成可能性.
科学领域:
- 生物催化和酶工程 生物催化和酶工程
- 有机合成 有机合成
- 蛋白质工程是指蛋白质工程.
背景情况:
- 野生类型的Candida antarctica脂酶A (CalA) 在特定的合成应用中具有活动和选择性的限制.
- 替代α的p-nitrophenyl的水解对于产生性化合物至关重要.
- 定向进化是改善酶特性的一种强大工具.
研究的目的:
- 设计一种Candida antarctica脂酶A (CalA) 的变体,以提高催化效率和改变基质特异性.
- 评估工程性脂酶对α-置换的p-尼托烯酸的水解的性能.
- 探索该酶变体在产生反聚合物纯化合物的合成效用.
主要方法:
- 使用定向进化来修改Candida antarctica脂酶A (CalA) 的氨基酸序列.
- 选酶变体,以提高各种α-置换的p-尼托烯酸的水解中的活性和酶选择性.
- 描述野生类型和进化的酶的动力参数 (E值) 和酶体过量 (ee).
主要成果:
- 进化的CalA变体显示了催化效率的大幅增加,E值在45-276之间,比野生类型 (2-20) 显著改善.
- 在广泛的经过测试的基质中,水解过程具有很高的反体过量 (95-99%).
- 大多数基质的活性显著增加了30倍,与野生类型的 (S) 选择性相比,与反向 (R) 选择性相结合.
结论:
- 工程 CalA 变体表现出显著增强的活性,广泛的基质范围和反转的反选择性,使其成为非对称合成的有价值的生物催化剂.
- 这种酶变体为高效和选择性生产性中间体提供了一个有前途的工具.
- 这项研究强调了定向进化在调整酶特性以应对特定合成挑战方面的成功.
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