对L-乳酸盐脱酶的性调节:超出了效应因子介导的四度化
Hanfeng Cai1, Smadar Shulami1, Zoran Štefanić2
1Department of Biotechnology and Food Engineering, Technion-Israel Institute of Technology, Haifa, Israel.
Protein science : a publication of the Protein Society
|June 26, 2025
概括
果糖1,6-双酸盐 (FBP) 稳定了L-乳酸脱酶 (GsLDH) 的结构,并通过促进特定的相互作用,而不仅仅是寡合化,增强了它的活性. 这项研究揭示了GsLDH中的全调节的分子基础.
科学领域:
- 生物化学 生物化学
- 结构生物学 结构生物学
- 酶动力学 酶动力学
背景情况:
- 整体调节的酶通过效应器诱导的结构变化表现出调节的活性.
- 来自Geobacillus stearothermophilus (GsLDH) 的L-乳酸盐脱酶被果糖1,6-双酸盐 (FBP) 激活,但其分子机制尚不清楚.
研究的目的:
- 通过分子动力学 (MD) 模拟和生物化学测试,研究FBP对GsLDH结构和功能的影响.
- 阐明GsLDH中FBP介导的全调节的分子基础.
主要方法:
- 分子动力学 (MD) 模拟用于分析结构变化和相互作用.
- MDavocado工具用于识别关键的二进制接口区域.
- 微热量计定位以研究NADH结合动力学.
- 生物化学试验涉及部位定向突变发生 (Gln189Leu) 以评估酶活性和全反应.
主要成果:
- FBP稳定了GsLDH四重体形式,降低了残留物灵活性,并增强了与活性部位残留物之间的pyruvate相互作用.
- 结合NADH取决于FBP的存在,这表明一种由度驱动的相互作用.
- Gln189Leu突变保持了四基结构,但未能诱导全转变,导致催化效率降低.
结论:
- 单独的寡合化对全反应不够;像FBP这样的效应因子介导的特定相互作用至关重要.
- FBP作为一个关键的全效应因子,稳定四级结构,并通过特定的分子相互作用改善GsLDH活性.
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