菌毒素candidalysin的分泌取决于保存的前体序列
Rita Müller1, Annika König1,2, Sabrina Groth3
1Department of Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Product Research and Infection Biology - Hans Knoell Institute (HKI), Jena, Germany.
Nature microbiology
|February 22, 2024
概括
在Candida albicans中的Ece1前体蛋白通过阻断candidalysin自聚,防止自我毒性. 非candidalysin Ece1对于这种真菌毒素的适当折叠和分泌至关重要.
科学领域:
- 菌类学 菌类学是指菌类学.
- 分子生物学分子生物学
- 病变的发生和发病.
背景情况:
- 香菌 (Candida albicans) 是一种机会主义的真菌病原体,它使用毒素candidalysin引起宿主细胞损伤.
- 甘素从真菌中通过前体蛋白质Ece1分泌出来,该蛋白质含有非甘素Ece1 (NCEPs).
- 目前尚不完全了解Ece1前体结构和NCEP在甘地素分泌中的作用.
研究的目的:
- 调查NCEPs在Ece1前体蛋白中的作用,在候选酶的折叠,分泌和毒性.
- 阐明Ece1前体防止自我毒性的机制.
主要方法:
- 在NCEP序列中删除或修改Ece1突变的构建和分析.
- 质谱法用于分析蛋白质相互作用和修饰.
- 用于检测和表征的纳米体中使用抗透分析.
- 评估突变对未折叠蛋白响应 (UPR),形形成和病原性 in vitro 的影响.
主要成果:
- Ece1的多蛋白结构与典型的毒素前体有所不同.
- 单个NCEP足以防止宿主细胞因candidatalysin而发生毒性.
- NCEPs对于正确的细胞内Ece1折叠和随后的候选酶分泌是必不可少的.
- 删除或修改NCEPs会触发一个未折叠的蛋白质反应 (UPR).
- 诱导UPR导致抑制菌形成,并降低了病原性.
结论:
- Ece1前体的主要作用不是防止过早的毒性,而是抑制candidalysin的细胞内自聚.
- NCEP对于维持Ece1蛋白质的稳态和调节甘地素分泌是至关重要的.
- 干扰NCEP功能会通过诱导UPR和损害状细胞发育影响C. albicans的毒性.
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