Mycobacterium tuberculosisCitA的活性是通过囊氧化和酸盐结合调节的
Rasangi Pathirage1, Lorenza Favrot2, Cecile Petit2
1Department of Pharmaceutical Sciences, University of Nebraska Medical Center Omaha NE 68198 USA don.ronning@unmc.edu.
RSC medicinal chemistry
|May 30, 2023
概括
结核菌MycobacteriumCitA,一种药物点,是由酸盐调节的,而不是NADH. 对C143的共价修饰使CITA失活,这表明了新的结核病药物策略.
科学领域:
- 生物化学 生物化学
- 结构生物学 结构生物学
- 药物发现 药物发现 药物发现
背景情况:
- 结核菌菌 (TB) 感染涉及休眠状态,CitA被确定为潜在的药物标.
- 过度表达CitA增强了缺氧下结核病的生长,并增加了抗生素的敏感性.
- 了解CITA的药物可用性和监管对于开发新的结核病疗法至关重要.
研究的目的:
- 确定CitA的晶体结构并阐明其调节机制.
- 评估CitA作为结核病药物标的潜力.
- 为了研究小分子化合物对CitA抑制.
主要方法:
- 在2.1 Å分辨率下解决CitA结构的X射线晶体学.
- 在酸盐结合口袋中的关键残留物 (R149,R153) 的位点定向突变发生.
- 蛋白质热转移试验用于评估连接体结合和热稳定性.
- 酶活性测定和IC50抑制剂的确定.
- 对CitA抑制剂复合物的结晶学分析.
主要成果:
- CitA结构显示没有NADH结合部位,但一种pyruvate分子表明pyruvate是全调节剂.
- 将R153转化为甲因增加了CitA的催化效率2.6倍.
- 由Ebselen对C143的共价修饰完全抑制了CitA活动.
- 两个螺旋环迈克尔受体抑制了CitA,其IC50值为6.6和10.9微米.
- 在Ebselen修改后,晶体结构显示出最小的变化.
结论:
- 酸盐,而不是NADH,在全质上调节CitA,提供了一个新的调节机制.
- 在Pyruvate位点附近的C143的共价抑制有效地使CitA无活化.
- CitA是一种可药物向的向,向C143为新型结核病疗法提供了一个有前途的战略.
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