KEAP1 C151活性部位催化驱动电友信号,以调节细胞保护性酶的表达
Matthew R Schnell1, Tianhua Zhai2, Edwin R Ragwan3
1Department of Chemistry and Biochemistry, Villanova University, Villanova, PA, 19085, USA; Department of Biochemistry and Biophysics, University of Pennsylvania, Philadelphia, PA, 19104, USA.
Redox biology
|November 4, 2025
概括
电友激活剂向KEAP1的C151氨酸,通过NRF2途径促进抗氧化反应. 这项研究揭示了C151的酶催化,解释了这些治疗电友的选择性向.
科学领域:
- 分子生物学分子生物学
- 生物化学 生化学
- 药理学 药理学是指药理学的学科.
背景情况:
- 细胞激活了对电友的排毒,抗氧化和抗炎反应,由NRF2转录因子介导.
- 电友性NRF2激活剂在治疗慢性疾病方面具有重要意义,主要向KEAP1 C151氨酸.
- 不同的电友选择性地准KEAP1 C151的机制尚不清楚.
研究的目的:
- 研究KEAP1 C151的pKa及其在选择性电结合中的作用.
- 阐明电友NRF2激活剂与KEAP1的优先反应的结构和催化基础 C151.1.
- 解释电友化合物如何通过KEAP1 C151向实现选择性药理作用.
主要方法:
- 使用化的醇反应电单博胺来确定KEAP1的pKa C151.1.
- 使用临床NRF2激活剂 (omaveloxolone,bardoxolone甲基,硫福拉) 和单微博胺进行了竞争性结合试验.
- 采用X射线晶体学和4D灵活对接模型来分析酶基质复合体和活性位点相互作用.
主要成果:
- 确定KEAP1 C151的pKa为6.9,在生理pH下优化其反应能力.
- 与小分子酸盐相比,单胺与KEAP1 C151呈现出意想不到的快速反应动力学.
- 对接研究表明,KEAP1活性部位通过疏水相互作用和关键键键结合容纳了多种激活剂,以引导电友进行催化接近.
- 建议将与α,β不和碳酸氧结合起到催化作用,增强电友性并稳定过渡状态.
结论:
- 在KEAP1 C151的酶催化是其对治疗性电友NRF2激活剂的选择性检测的主要驱动因素.
- 活性部位的独特特性有利于与C151相比其他细胞半氨酸的反应,解释了这些化合物的选择性.
- 电友对C151活性部位的动态向支持它们作为选择性药理学剂的有效性.
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