环境pH控制人类益生菌Streptococcus salivarius的抗菌生产
Dieu Linh Nguyen1,2, Subhasree Saha1,2, Aswin Thacharodi1,2
1Center for Molecular and Translational Human Infectious Diseases Research, Houston Methodist Research Institute, Houston, Texas, USA.
Journal of bacteriology
|June 2, 2025
概括
口服益生菌Streptococcus salivarius K12产生抗微生物唾液菌素,在酸性环境中最有效. 酸化通过pH敏感的调节系统触发了唾液菌素的产生,从而提高了其益生菌的有效性.
科学领域:
- 微生物学 微生物学
- 分子生物学分子生物学
- 益生菌 益生菌 益生菌
背景情况:
- *Streptococcus salivarius* K12 (SAL) 是一种口服益生菌,用于预防感染.
- 盐可以产生像唾液菌素这样的抗微生物药物,但其产量是暂时的,可能会限制有效性.
- 影响SAL抗菌活性和生产的环境因素尚未完全理解.
研究的目的:
- 为了研究环境pH对S. salivariusK12的唾液菌素生产和抗菌活性的影响.
- 为了阐明调节在pH值变化时产生的唾液菌素的分子机制.
主要方法:
- 评估了环境pH对*sar-BGC*表达和唾液菌素产生的影响.
- 研究了定数感应系统和NrpR调节器在pH依赖调节中的作用.
- 分析了NrpR,NIP和细胞质pH之间的相互作用.
主要成果:
- 环境酸化显著诱导sar-BGC的表达和唾液菌素的产生.
- 酸性pH直接影响控制 *sar-BGC* 表达的定数感应系统.
- 细胞酸酸化导致NrpR质子化,增强其与NIP的相互作用,并上调*sar-BGC*表达.
结论:
- *S. salivarius* K12利用一个复杂的pH感应机制来协调唾液菌素的产生.
- 环境酸化对于最大限度地提高唾液巴克的抗菌活性和益生菌疗效至关重要.
- 了解这种调节途径可以为改善益生菌性能的策略提供信息.
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