在βB2-晶体中ATCUN类的铜部位在白内障相关聚合中起着保护作用
Martin E Tovar-Ramírez1, Nils Schuth1, Oscar Rodríguez-Meza2
1Department of Chemistry, Centro de Investigación y de Estudios Avanzados (Cinvestav), Mexico City 07360, Mexico.
Inorganic chemistry
|June 28, 2023
概括
双价金属离子如,,铜和可以导致人类βB2-晶聚合,这是白内障形成的关键因素. 在βB2-晶体中发现了包括保护性N端基因在内的铜结合部位,影响其聚合和稳定性.
科学领域:
- 生物化学 生物化学
- 眼科医生 眼科 眼科
- 蛋白质化学 蛋白质化学
背景情况:
- 白内障是全球失明的主要原因,是由于晶体损伤和聚合造成的.
- 透镜晶体,特别是βB2-晶体,是丰富的结构蛋白,易受金属离子诱导的聚合.
- 老年白内障镜片中金属含量升高表明金属离子在疾病发病过程中的作用.
研究的目的:
- 为了研究双价金属离子对人类βB2-晶体聚合物的影响.
- 为了阐明铜诱导的βB2-晶聚合的机制.
- 为了识别和描述βB2-晶体内的铜结合点.
主要方法:
- 度测试用于监测蛋白质聚合.
- 循环二重化和电子磁共振 (EPR) 光谱用于结构和结合位点分析.
- 异热定位热量计 (ITC) 用于确定金属离子的结合亲和力.
- 射线吸收光谱 (XAS) 用于研究铜的氧化还原状态和协调.
主要成果:
- Pb2+,Hg2+,Cu2+和Zn2+诱导了βB2-晶体聚合,可通过化剂部分逆转.
- 铜诱导的聚合包括金属桥接,二硫化物桥接,以及蛋白质稳定性的丧失.
- 确定了至少三个Cu2+结合位点,包括一个具有纳米分子亲和力的N端ATCUN样模因,可以防止聚合并增强热稳定性.
结论:
- 二元金属离子促进βB2-晶聚合,有助于白内障的形成.
- 在βB2-晶体中N端的ATCUN样铜结合部位起着保护作用.
- 需要进一步的研究来确定这种铜结合部位在镜片生理和进化的功能意义.
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