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.
bioRxiv : the preprint server for biology
|August 6, 2025
概括
研究人员发现了细菌ABC载体是如何识别ergothioneine (ET) 的. EgtUC蛋白中的特定CH•••S键是结合这种重要的抗氧化剂的关键,揭示了新的分子识别机制.
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) 载体进行营养吸收和其他功能.
- 欧戈氨酸 (ET) 是一种低分子量硫醇和一种在各种生物体中发现的人类饮食抗氧化剂.
- EgtU 载体及其溶解物结合域 EgtUC 对于 ET 具有特异性,但识别机制尚不清楚.
研究的目的:
- 阐明EgtUC蛋白通过哪些分子机制来区分从其他分子中的ergothioneine (ET).
- 确定负责ET被EGTUC选择性结合的特定相互作用.
主要方法:
- 采用了一种"化学"突变发生策略,涉及来自*Streptococcus pneumoniae*和*Helicobacter pylori*的EgtUC蛋白质.
- 研究了特定的键的作用,特别是基CH•••S相互作用,在蛋白质-连接体识别.
- 分析了键距离和结合角度的小扰动对结合亲和力和蛋白质动态的影响.
主要成果:
- 确定了一套EgtUC基CH•••S键,对于识别ET的硫原子至关重要.
- 证明这些CH•••S债券的轻微变化显著降低了运输能力ET-bound"关闭"状态的稳定性.
- 由于NH•••O键减弱,观察到与硫原子距离的结合口袋中运动障碍增加.
结论:
- 基CH•••S键是EgtUC载体对ergothioneine分子识别的核心决定因素.
- 这项研究首次描述了基CH•••S H-结合在水性环境中的生物蛋白-连接体综合体中的作用.
- 了解这些相互作用可以为设计新型治疗剂或针对ABC载体的诊断工具提供信息.
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