分子工程的有机酸盐水解活性从一个弱的乱交乳酶模板
Monika M Meier1, Chitra Rajendran, Christoph Malisi
1Institute of Biophysics and Physical Biochemistry, University of Regensburg, Regensburg, Germany.
Journal of the American Chemical Society
|July 11, 2013
概括
研究人员从一个散乱的酶支架中设计了一种新型的有机酸盐酸酶 (OPH). 这种工程化OPH表现出显著提高的催化效率和广泛的基质特异性,用于有机酸盐降解.
科学领域:
- 酶学 是一种酶学.
- 蛋白质工程是指蛋白质工程.
- 生物催化剂是一种生物催化剂.
背景情况:
- 酶进化提供了对蛋白质适应性和结构功能关系的见解.
- 来自Pseudomonas diminuta的三酶 (PTE) 是一种高效的有机酸盐酸酶.
- 假设PTE是从具有乱交活动的三酶类乳酶 (PLL) 进化而来的.
研究的目的:
- 从无序的三酶类乳酶 (PLL) 支架中设计一个高效的有机酸盐酸酶 (OPH).
- 研究PLL和PTE之间的进化关系.
- 阐明增强催化活性的分子基础.
主要方法:
- 一个PLL支架的理性和随机突变发生 (Dr0930).
- 对于有机酸盐水解的体外活性查.
- 工程变体的结构和计算分析.
主要成果:
- 设计了一个高达5个数量级的OPH,对7个有机基质增强了活性.
- 获得的催化效率高达10^6 M^-1 s^-1.
- 在工程 OPH 和本地 PTE 之间确定了不同的基质结合和催化机制.
结论:
- 从一个弱性散乱的PLL中证明了高效的OPH的成功工程.
- 提供了对催化效率和基质特异性演变的分子见解.
- 突出了工程PLL和自然PTE之间OPH催化中的显著差异.
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