保存的 σD 包裹应激反应监测了角膜细菌包裹完整性的多个方面
Elizabeth M Hart1,2, Evan Lyerly1,2, Thomas G Bernhardt1,2
1Department of Microbiology, Harvard Medical School, Boston, Massachusetts, United States of America.
PLoS genetics
|June 3, 2024
概括
研究人员确定了真菌细菌细胞外的关键调节者,并揭示了 σD 应激反应如何监测真菌酸和阿拉比诺的组合,以进行适当的蛋白质出口.
科学领域:
- 微生物学 微生物学
- 细菌细胞外 生物学 生物学
背景情况:
- 菌根菌种具有独特而复杂的细胞外,对于它们的毒性至关重要.
- 这种包裹包括外层菌膜 (MM) 层和细胞壁,有助于抗生素耐药性.
- 了解包膜生物生成对于识别针对Mycobacterium tuberculosis等病原体的新治疗点至关重要.
研究的目的:
- 为了研究控制Corynebacterium glutamicum中膜 (MM) 生物发生的机制.
- 确定MM中蛋白质的适当表面暴露所涉及的遗传因素.
- 阐明应激反应途径在维持细胞外完整性的作用.
主要方法:
- 开发基于细胞分类的屏幕,以识别菌表面暴露缺陷的突变动物.
- 保存的σD外应激反应路径的特征.
- 确定MarP是激活 σD反应的位点-1蛋白酶.
- 使用报告系统来监测 σD 途径的激活,以应对包膜生物合成缺陷.
主要成果:
- 保存的σD外应力反应对于蛋白向菌膜输出至关重要.
- MarP蛋白酶被确定为 σD 途径的激活剂,通过分裂抗西格玛因子.
- 这种 σD 途径是由酸和阿拉比诺银生物合成中的缺陷诱导的.
- 这表明 σD 途径监测了不同的细胞外层的组装.
结论:
- 在C. glutamicum中 σD应激反应监测多个细胞外层的完整性.
- 这条通路是由受损的醇酸和阿拉比诺甲酸合成引起的信号激活的.
- σD regulon的成员可能在蛋白质出口到菌膜中发挥重要作用.
- 这些发现提供了细菌包膜恒温和潜在的抗生素点的见解.
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