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Comparing the Affinity of GTPase-binding Proteins using Competition Assays
Published on: October 8, 2015
在谷氨酸酸赛马酶中催化功率和连接体结合的决定因素
M Ashley Spies1, Joseph G Reese, Dylan Dodd
1Department of Biochemistry, Institute for Genomic Biology, University of Illinois, Urbana, Illinois 61801, USA. aspies@life.uiuc.edu
Journal of the American Chemical Society
|March 25, 2009
概括
谷氨酸赛马酶 (RacE) 使用分布式静电相互作用,而不是强键,来结合中间体. 这一发现是设计针对细菌细胞壁合成的新抗菌剂的关键.
科学领域:
- 生物化学 生物化学
- 酶学 是一种酶学.
- 结构生物学 结构生物学
背景情况:
- 谷氨酸种族酶 (EC 5.1.1.3) 对于细菌活力至关重要,它催化了酸盐的立体反转,用于类甘油的合成.
- 它们是抗菌药物开发的有希望的目标,但由于物种特异性,抑制剂的设计具有挑战性.
- 这些酶的催化机制和活性部位相互作用仍然不完全理解.
研究的目的:
- 为了研究来自 Bacillus subtilis (RacE) 的谷氨酸赛马酶的催化机制.
- 为了阐明RacE及其谷氨酸碳酸盐中间体之间的相互作用.
- 为设计辅因子独立的种族质的高亲缘关系联体提供见解.
主要方法:
- 综合计算和实验方法.
- 分析RacE-酸盐复合物的晶体结构.
- 在基和实验性位点定向突变发生.
- 酶 - 配方体相互作用能量计算.
主要成果:
- 拉塞-谷氨酸-氨酸复合物的活性形式与拉塞-D-谷氨酸复合物有显著差异.
- 对于carbanion中间体,观察到显著更强的酶-连接体相互作用能量.
- 相互作用强度归因于在活性位点内的分布式静电相互作用,而不是主导的键.
结论:
- RacE的催化功率依赖于活性部位的静电相互作用网络.
- 了解这些相互作用对于克服开发特定和强效抗菌剂的挑战至关重要.
- 这项研究为合理的药物设计奠定了基础,目标是细菌的谷氨酸谷氨酸种族酶.
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