宿主蛋白质体的降解产生了对于细胞内细菌生长必不可少的氨基酸
Christopher T D Price1, Tasneem Al-Quadan, Marina Santic
1Department of Microbiology and Immunology, College of Medicine, University of Louisville, KY 40202, USA.
概括
肺菌使用其AnkB效应器触发宿主细胞蛋白质分解,产生氨基酸,这对于杏仁菌,人类细胞和小鼠的细菌生长至关重要.
科学领域:
- 微生物学 微生物学
- 细胞生物学 细胞生物学
- 生物化学 生物化学
背景情况:
- 肺炎菌 (Legionella pneumophila) 是一种细胞内细菌,在一个专门的真空体 (LCV) 中复制.
- 细菌效应物准LCV膜,包括AnkB F-box蛋白,该蛋白通过宿主法尼基化定.
- 了解营养获取策略对于控制军团菌感染至关重要.
研究的目的:
- 研究AnkB在Legionella pneumophila营养获取中的作用.
- 为了确定Legionella如何利用宿主细胞机械进行其增殖.
- 为了识别宿主衍生资源对于细胞内细菌生存至关重要.
主要方法:
- 产生和分析Legionella pneumophila的AnkB无基因突变体.
- 在宿主细胞 (阿米巴,人类细胞) 和体内 (小鼠) 中评估细菌的增殖.
- 用氨基酸,氨酸,氨酸,酸盐或酸盐进行补充测定,以拯救突变的表型.
主要成果:
- 通过AnkB的介导,LCV上的Lys(48) 结合的多比基化蛋白质的宿主蛋白质体降解产生氨基酸.
- B突变体在阿米巴和人类细胞中表现出严重的增殖缺陷,这些细胞通过氨基酸补充物得到拯救.
- 在小鼠的ankB突变的肺内扩散缺陷也通过氨基酸或氨酸注射得到拯救.
结论:
- 肺炎菌 (Legionella pneumophila) 积极劫持宿主蛋白酶体系统,以降低宿主蛋白质的质量.
- 生成的氨基酸作为细菌繁殖的关键碳和能源.
- 这种营养获取机制在进化上遥远的宿主中得到保护,突出了军团菌的关键生存策略.
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