达普托素对细胞壁生物合成的作用 在肠球菌体中
Binayak Rimal1,2, James Chang3, Chengyin Liu4
1Institute of Biomedical Studies, Baylor University, Waco, TX, 76798, USA.
Scientific reports
|July 28, 2023
概括
达普托米辛治疗通过扰乱丁糖的交叉连接和成熟来稀薄细菌细胞壁,而不是通过抑制前体合成. 这导致对降解的易感性增加,影响多药耐药的格拉姆阳性感染.
科学领域:
- 微生物学 微生物学
- 抗生素耐药性 抗生素耐药性
- 生物化学 生物化学
背景情况:
- 达普托米辛是治疗由多抗药性格拉姆阳性细菌引起的感染的关键抗生素.
- 其已知的机制包括细菌膜脱极化,但其对细胞壁生物合成的精确影响需要进一步澄清.
研究的目的:
- 阐明达普托米辛对细菌细胞壁生物合成作用的详细机制.
- 调查达普托米辛是否抑制丁糖原体的合成或影响细胞壁成熟.
主要方法:
- 使用15N交叉极化魔法角旋转NMR对*金黄色葡萄球菌*进行细胞壁组件分析.
- 采用液体染色学和质谱法来量化*Enterococcus faecalis*中的甘氨酸修饰.
主要成果:
- 达普托米辛治疗导致 *S. aureus* 细胞壁变薄,而没有积累丁糖素前体.
- 在*E. faecalis*中,达普素显著降低了甘氨酸的交叉连接和茎的修饰,增加了酸转糖酶的活性.
- 核磁共振 (NMR) 数据表明,没有抑制酸甘生物合成中的转糖酶化步骤.
结论:
- 达普托米辛通过阻碍丁糖的结合和成熟来抑制细菌细胞壁生物合成,而不是抑制前体合成.
- 这种干扰使细胞壁易受自溶性降解,有助于抗生素对抗耐药性病原体的疗效.
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