甲尼尔-tRNA合成酶的合成和校对活动是抗生素持久性的决定因素
Whitney N Wood1,2, Miguel Angel Rubio1, Lorenzo Eugenio Leiva2
1Department of Microbiology, The Ohio State University, Columbus, OH, United States.
Frontiers in microbiology
|April 11, 2024
概括
细菌抗生素持久性是一种生存策略,由metG基因的突变增强. 这些变化扰乱了蛋白质合成和同氨酸代谢,增加了在抗生素暴露期间的细菌存活率.
科学领域:
- 微生物学 微生物学
- 分子生物学分子生物学
- 遗传学 遗传学 是一个
背景情况:
- 细菌抗生素持久性允许一个小小的亚群通过进入休眠状态来生存抗生素治疗.
- 蛋白质合成扰乱是细菌抗生素持久性的潜在机制.
- 该metG基因编码Methionyl-tRNA合成酶 (MetRS),对于蛋白质合成至关重要.
研究的目的:
- 研究metG突变在细菌抗生素耐药性中的作用.
- 为了确定改变的MetRS功能是否会影响翻译启动或延长.
- 探索MetRS活性,同型氨酸代谢和抗生素持久性之间的联系.
主要方法:
- 四种不同的metG突变的特征与MetRS催化或抗结合域的变化.
- 评估metG突变体和野生型株的抗生素持久性水平,其metG转录率降低.
- 在突变菌株中分析MetRS活性,翻译率和同型半氨酸校对.
主要成果:
- 所有四种metG突变和减少的野生型metG转录都显著增加了抗生素持久性.
- MetRS变体没有改变MetRS酶活性,但降低了整体翻译率.
- MetRS变种影响了同类氨酸校对,导致突变生长中的同类氨酸过敏.
结论:
- 蛋白质合成中断,特别是通过metG突变,增强了细菌抗生素的持久性.
- 细胞氨酸-tRNA合成能力的降低和MetRS对同类氨酸的校对受损是抗生素耐药性的关键决定因素.
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