人类calprotectin的高亲和度协调是依赖的,需要在二聚体接口形成的富含histidine的位点
Joshua A Hayden1, Megan Brunjes Brophy, Lisa S Cunden
1Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Journal of the American Chemical Society
|January 2, 2013
概括
蛋白质 (CP) 在特定的His (His) (4) 位点捕获 (Mn (II)),并增强了. 这种蛋白质合金属以抑制微生物生长,特别是在对梯度的反应中.
科学领域:
- 生物化学 生物化学
- 结构生物学 结构生物学
- 微生物学 微生物学
背景情况:
- 蛋白 (CP) 是一种由中性粒细胞产生的抗菌蛋白.
- 通过和等过渡金属离子的化,CP抑制了微生物的生长.
- CP的S100A8/S100A9二元接口形成了不同的金属结合点.
研究的目的:
- 为了研究Calprotectin (CP) 的结合特性.
- 为了表征S100A8/S100A9二次体内的特定协调位.
- 了解在调节CP的金属结合亲和力和选择性的作用.
主要方法:
- 低温电子偏磁共振 (EPR) 光谱检测Mn2结合.
- 位点定向突变发生,以确定关键的协调残留物.
- 金属离子选择性测试比较和的结合.
主要成果:
- 在S100A8/S100A9二元接口上的His(4) 动图是高亲和度Mn(II) 结合点.
- 光谱分析显示,在这个位置有一个八面体的Mn2协调球.
- 结合显著增加了Mn{\displaystyle Mn} 的亲和力,而CP对Zn{\displaystyle Zn} 的选择性更高.
结论:
- CP利用His(4) 位点进行高亲和度Mn(II) 协调,受水平的影响.
- 混合 Zn:Mn:CP 复合物的形成是有利的.
- CP作为一种调节的,高亲和度的金属化剂,以细胞外抑制微生物生长.
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