洞察到基酶合成酶的糖基酶活性部位:一个计算研究
Vivek S Bharadwaj1, Anthony M Dean, C Mark Maupin
1Chemical and Biological Engineering Department, Colorado School of Mines, 1500 Illinois Street, Golden, Colorado 80401, USA.
Journal of the American Chemical Society
|July 20, 2013
概括
酸合成酶 (BSS) 使用计算方法揭示微生物如何分解碳化合物. 这项研究揭示了酶的活性部位,这对无氧能量产生至关重要.
科学领域:
- 生物化学 生物化学
- 酶学 是一种酶学.
- 微生物的新陈代谢
背景情况:
- 基酸合成酶 (BSS) 催化了一种具有挑战性的烟酸添加反应.
- 这种反应对于微生物无氧代谢碳化合物至关重要.
- BSS的糖基的氧气敏感性限制了之前的结构和动力学研究.
研究的目的:
- 通过计算推断BSS的催化子单位 (BSSα) 的结构.
- 阐明由BSS.催化的烟酸添加反应背后的分子机制.
- 了解BSS如何促进微生物中的碳化合物利用.
主要方法:
- 同性学建模的模拟.
- 分子对接研究分子对接研究.
- 分子动力学 (MD) 模拟
主要成果:
- 在BSSα活性部位中分别发现了和烟酸的明显的疏水和极结合口袋.
- 确定了关键的活性部位残留物 (Glu509,Ser827,Leu390,Phe384),对基质结合至关重要.
- MD模拟显示了基质诱导的活性部位收紧和基质辅助的基因转移途径.
结论:
- 计算建模为BSS功能和烟酸添加机制提供了分子洞察力.
- 已确定的活性站点架构和残留物对于BSS催化是至关重要的.
- 了解BSS是理解微生物无氧碳化合物代谢的关键.
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