CH•••S 键驱动微生物载体对厄戈氨的分子识别
Katherine A Legg1, Giovanni Gonzalez-Gutierrez2, Katherine A Edmonds1
1Department of Chemistry, Indiana University, Bloomington, IN, USA.
Science advances
|February 20, 2026
概括
细菌的ABC载体使用特定的CH•••S键来识别饮食中的抗氧化剂 - - ergothioneine (ET). 这些键的微妙变化会破坏ET的结合和传输,影响细菌的功能.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 微生物学 微生物学
背景情况:
- 细菌利用ATP结合盒 (ABC) 载体,如EGTU,来进口欧戈氨酸 (ET).
- ET是一种含有2-thioimidazole部分的人类饮食抗氧化剂.
- 通过EgtU溶解物结合域 (EgtUC) 区分ET与类似分子的机制尚不清楚.
研究的目的:
- 阐明了对ergothioneine的EgtUC载体的分子识别机制.
- 确定负责EGTUC.特异性的关键相互作用.
主要方法:
- 采用了使用 *Streptococcus pneumoniae* 和 *Helicobacter pylori* *的 EgtUC 蛋白质进行嵌合式突变发生的策略.
- 研究了特定键在蛋白质 - 配体相互作用中的作用.
- 分析了结构性扰动对结合口袋动态和封闭状态寿命的影响.
主要成果:
- 确定了一系列EgtUC基CH•••S键,对于识别ET硫原子至关重要.
- 证明CH•••S键形状的微小变化显著降低了对运输有能力的封闭状态的稳定性.
- 观察到结合口袋中的运动障碍增加,与偏远NH•••O键的削弱有关,而不是在硫原子周围的直接影响.
结论:
- 基CH•••S键是通过EGTUC.的ergothioneine分子识别的中心决定因素.
- 这项研究强调了CH•••S H-结合在水环境中的生物蛋白-连接体识别中的重要作用.
- 精确的键几何结构对于维持载体-连接体复合体的功能性构造和稳定性至关重要.
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