营养物质限制使人变得更加敏感
Derek C K Chan1, Katherine Dykema1, Mahrukh Fatima1
1David Braley Center for Antibiotic Discovery, Michael G. DeGroote Institute for Infectious Disease Research, Department of Biochemistry and Biomedical Sciences, McMaster University, 1280 Main Street West, Hamilton, Ontario L8S 4K1, Canada.
ACS infectious diseases
|June 6, 2023
概括
在营养有限的条件下对抗生素进行查,发现了万科米.
科学领域:
- 微生物学 微生物学
- 抗生素耐药性 抗生素耐药性
- 细菌病原体的产生
背景情况:
- 标准的抗菌查方法使用营养丰富的条件,不反映自然环境或感染地点.
- 从生理学上相关的查条件可能会揭示新的抗生素活性.
- Pseudomonas aeruginosa 是一种机会主义的阴性细菌.
研究的目的:
- 在营养和铁含量低的条件下,选针对Pseudomonas aeruginosa报告不活性的抗生素.
- 识别新型抗生素活动,了解新出现的抗药性机制.
主要方法:
- 在低营养和低铁条件下对 Pseudomonas aeruginosa 抗生素的查.
- 对万科米辛耐药机制的分析,包括遗传突变及其对细胞过程的影响.
- 脂多糖 (LPS) 概况和耐药突变体中的菌体敏感性的表征.
主要成果:
- 范科米辛在低微分子度下通过丁糖交叉连接的破坏显示出对Pseudomonas aeruginosa的抑制活性.
- 旺科米辛耐药性源于CpxSR双组分系统的突变,使其对β-乳糖胺和 cefiderocol产生交叉耐药性.
- 在LPS生物合成酶WapR的突变也赋予了万科米辛耐药性和改变了LPS结构,增加了菌体的敏感性.
结论:
- 在营养有限的条件下进行查,可以发现存在的抗生素 (如万科米辛) 对格拉姆阴性细菌的新活动.
- 发现新的抗药性机制,如涉及CpxSR和WapR的抗药性机制,对于了解抗生素疗效至关重要.
- 这种方法突出了通过模仿真实世界的细菌环境来寻找新的治疗策略的潜力.
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