利基-tRNA-合成酶 (LeuRS) 的时间依赖抑制:洞察目标脆弱性
Mingqian Wang1, YongLe He1, Siobhan A Cohen1
1Center for Advanced Study of Drug Action, and Department of Chemistry, Stony Brook University, Stony Brook, New York 11794-3400, United States.
ACS infectious diseases
|April 2, 2025
概括
本佐xaboroles通过准leucyl-tRNA合成酶来抑制细菌蛋白质合成. 将它们与托布拉米辛结合,通过减少酶合成来增强后抗生素效应 (PAE),提供新的剂量策略.
科学领域:
- 微生物学 微生物学
- 药理学 药理学是指药理学的学科.
- 生物化学 生物化学
背景情况:
- 后抗生素效应 (PAE) 对于优化抗菌剂剂量方案至关重要.
- 了解药物标相互作用和蛋白质循环是阐明PAE机制的关键.
研究的目的:
- 调查佐xaborols的抗生素后作用 (PAE),以向大肠杆菌的leucyl-tRNA合成酶 (ecLeuRS).
- 评估托布拉米对可萨醇诱导的PAE和ecLeuRS合成的影响.
主要方法:
- 用时间依赖的抑制试验来研究佐xaboroles 的ecLeuRS抑制.
- 在大肠杆菌中测量了后抗生素效应 (PAE),其中有或没有托布拉米辛的亚抑制度.
- 使用 pSILAC 来量化 ecLeuRS 合成速率的变化.
主要成果:
- 包括epetraborole在内的benzoxaboroles显示出缓慢结合的ecLeuRS抑制,显著降低了IC50值.
- 单独使用本佐xaborols观察到短时间的PAE (<1小时),但与托布拉米结合时增加到1.70-3小时.
- 亚抑制性托布拉米辛将ecLeuRS合成降低了1.6倍,这表明蛋白质循环在目标脆弱性中的作用.
结论:
- 本佐xaboroles有效地抑制ecLeuRS,并观察到增强的结合亲和力.
- 佐xaboroles和托布拉米的组合增强PAE,表明协同作用.
- 蛋白质周转显著影响标脆弱性和整体后抗生素效应,为未来的抗菌药物开发提供信息.
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