用于细胞壁生物合成和降解控制的细胞质中间体诱导了格拉姆阴性细菌中可诱导的β-乳糖耐药性
Cell
|March 21, 1997
概括
格兰阴性细菌使用AmpR和muropeptides控制beta-lactamase的产生. 墨酸具有对抗性的作用,其中UDP-MurNAc-pentapeptide抑制,AnhMurNAc-tripeptide恢复了AmpR激活β-乳酸酶合成的作用.
科学领域:
- 微生物学 微生物学
- 分子生物学分子生物学
- 生物化学 生物化学
背景情况:
- 在グラム阴性细菌中的β-乳酸酶诱导对于抗生素耐药性至关重要.
- 这一过程需要转录调节器AmpR和细胞质木质.
研究的目的:
- 为了阐明beta-lactamase (ampC) 基因表达的调节机制.
- 研究muropeptides在控制AmpR介导的转录激活中的作用.
主要方法:
- 在体外转录试验中,使用纯化的AmpR.R.进行了转录试验.
- 对构成性AMPC激活的AmpR突变 (例如,AmpR(G102E)) 的分析.
- 测试特定的墨 (UDP-MurNAc-pentapeptide,anhMurNAc-tripeptide) 对AmpR活性的影响.
主要成果:
- 纯化的AmpR在体外激活AMPCβ-乳糖酶合成.
- UDP-MurNAc-pentapeptide抑制了AmpR介导的激活,但不是在一个组成的AmpR突变中.
- MurNAc-三抗 UDP-MurNAc-五的抑制,恢复 AmpR 的诱导能力.
结论:
- 细胞结合性木氨酸中间体具有对抗作用,可以调节β-乳糖酶的表达.
- 这个系统作为细胞壁传感机制,控制抗生素耐药性的功能.
- 了解这种途径为新型抗微生物战略提供了潜在的目标.
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