酸化强烈影响人类碳酸酶I CO2水活动的抑制
Andrea Angeli1, Vivian De Luca2, Xiaojing Huang3
1Neurofarba Department, Pharmaceutical and Nutraceutical Section, University of Florence, Sesto Fiorentino, Italy.
Archives of biochemistry and biophysics
|October 16, 2024
概括
在Ser51的酸化显著改变了人类碳酸酶I (hCA I) 功能,降低了其催化效率,并大大改变了其对抑制剂的敏感性. 这影响了对hCA I的理解.
科学领域:
- 生物化学 生物化学
- 酶学 是一种酶学.
- 分子生物学分子生物学
背景情况:
- 人类碳酸无水酶 (hCA) 对生理过程至关重要,并与各种疾病有关.
- 人类CA I (hCA I) 在红细胞中丰富,对二氧化碳运输至关重要.
- 翻译后修饰 (PTMs) 的影响,特别是酸化,对hCA I活性和抑制剂结合的影响尚不清楚.
研究的目的:
- 研究hCA I.中保存的Ser51残留物酸化的功能后果.
- 为了检查相仿性突变 (S51E) 对hCA I的催化效率和抑制剂敏感性的影响.
主要方法:
- 利用复合表达系统产生野生类型和S51E突变hCA I.
- 使用停止流动的动力测试来测量二氧化碳水活性.
- 使用41个硫胺和37个小离子的小组评估抑制动力学.
主要成果:
- S51E突变增加了催化周转率 (kcat),但显著降低了基质亲和力 (KM),将整体催化效率降低了50%以上.
- S51E hCA I对硫胺胺抑制剂的敏感性发生了显著的变化,最有效的抑制剂变得效果超过35倍.
- 突变者对37个测试的离子中24个的敏感性显著降低,其中一些KI增加了多达11000倍.
结论:
- 在Ser51的酸化深刻影响hCA I的催化活性和抑制剂结合特征.
- 这些发现强调了考虑PTM对于理解酶功能和药物开发的重要性.
- 鉴定蛋白形特异性抑制是开发更有针对性的碳酸 anhydrase 相关疾病治疗方法的关键一步.
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