通过SpuA介导的葡萄糖代谢通过酸和氨基酸利用Streptococcus pneumoniae调节酸性压力适应
Weichen Gong1,2,3, Masayuki Ono2, Xuefei Cheng4
1Laboratory of Animal Food Function, Graduate School of Agricultural Science, Tohoku University, Sendai 980-8572, Japan.
Microorganisms
|October 29, 2025
概括
在Streptococcus pneumoniae中缺少SpuA酶会导致酸的产生增加,改变细菌的新陈代谢和应激反应. 这种代谢转变会影响细菌在感染期间的生长和持续性.
科学领域:
- 微生物学 微生物学
- 细菌生理学 细菌生理学
- 病原体适应 病原体适应
背景情况:
- 糖原代谢对于细菌的适应至关重要.
- 糖原降解酶SpuA在Streptococcus pneumoniae中的作用尚不清楚.
- 研究SpuA的功能是了解S. pneumoniae的生存策略的关键.
研究的目的:
- 为了阐明SpuA在Streptococcus pneumoniae中的生理意义.
- 确定SpuA如何影响细菌生长和酸性应激反应.
- 在没有SpuA的情况下探索S. pneumoniae的代谢适应性.
主要方法:
- 野生类型和 ΔspuA Streptococcus pneumoniae 菌株的比较分析.
- 在各种条件下进行体外生长测定.
- 鼠标感染模型来评估细菌负载和宿主反应.
- 转录组分析以确定基因表达变化.
- 代谢物概况分析以分析代谢变化.
主要成果:
- ΔspuA菌株产生了更多的酸性代谢物,并表现出延迟的初始生长,但在体内增加了以后的持久性.
- ΔspuA菌株对酸的耐受性增加,血清粉样蛋白A1摄入量增加.
- 转录基因数据表明,在ΔspuA菌株中氨基酸利用率降低,特别是囊.
- 酸补充恢复了氨基酸利用率,并增强了ΔspuA的生长,这表明酸和氨基酸代谢之间存在联系.
结论:
- 缺少SpuA促使S. pneumoniae的新陈代谢转向酸生产,影响基因表达和应激耐受性.
- 这种适应促进了在酸性,低氧环境中生长,这是感染的特征.
- SpuA可能会限制细菌过度生长,促进宿主-病原体平衡.
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