酵母表现出一种动力效率高的13氨基酸基质的演化,用于脂酸结合酶
Sujiet Puthenveetil1, Daniel S Liu, Katharine A White
1Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA.
Journal of the American Chemical Society
|October 30, 2009
概括
研究人员为大肠杆菌的脂酸酶 (LplA) 设计了一种新的基质,LAP2. 这种工程可以增强LplA.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 生物技术是生物技术.
背景情况:
- 大肠杆菌的脂酸链酶 (LplA) 对于将脂酸连接到参与氧化代谢的蛋白质至关重要.
- LplA可以被设计为结合小分子探针,帮助成像和蛋白质组学.
- 自然的LplA基质具有β-hairpin结构,难以在短中复制.
研究的目的:
- 为了加深对脂酸代谢的理解.
- 增强LplA作为一个多功能生物技术平台的实用性.
- 为LplA.设计一种新的,高效的基质.
主要方法:
- 酵母表面显示的类库 (LplA受体,LAP) 的体外演化.
- 光激活细胞分类 (FACS) 用于有效隔离标记的LAP变体.
- 动力特征和理性突变发生,以优化序列.
主要成果:
- 工程LAP2基质实现了0.99μM-1分钟-1的k(cat) /K(m,比之前的LAP1序列改进了70倍以上.
- LAP2的动力效率与天然的脂酸盐和生物素受体蛋白相美.
- 改进的动力学使细胞表面受体能够快速用量子点标记.
结论:
- 工程LAP2代表了LplA基质设计的重大进步.
- 这种改进的基板扩大了LplA在生物技术应用中的实用性,包括生物成像.
- 这项研究证明了体外进化在制造量身定制的酶基质方面的力量.
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