调节由Lacticaseibacillus paracaseiL9中的酸耐受性反应驱动的异质性
Zhichao Shen1,2, Li Lin1, Zhengyuan Zhai1
1College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China.
Foods (Basel, Switzerland)
|November 14, 2023
概括
酸适应增强了乳酸细菌的耐受性. 该研究显示,bglG基因调节了酸耐受性反应 (ATR) 的异质性,改善了Lacticaseibacillus paracasei L9的存活率.
科学领域:
- 微生物学 微生物学
- 分子生物学分子生物学
- 生物化学 生物化学
背景情况:
- 酸耐受性对于乳酸细菌 (LAB) 在发酵和益生菌应用中至关重要.
- 酸适应增强了LAB的酸耐受性,在酸耐受性反应 (ATR) 下的表型异质性提供了生存优势.
- 驱动ATR诱导异质性的精确机制仍然不清楚,尽管涉及个体基因表达差异.
研究的目的:
- 在酸性压力下调查L9 (L9) Lacticaseibacillus paracasei种群的异质性.
- 确定调节这种异质性的关键基因,并阐明它们在酸耐受性反应 (ATR) 中的作用.
- 为提高L. paracasei L9.9的酸性耐受性提供理论基础.
主要方法:
- 在pH值为5.0的L. paracasei L9的酸适应40分钟.
- 流式细胞计量用于观察和分类异质子群 (可活,受伤,死亡,未染色).
- 用基因表达诱导和突变发生来对分类亚种群进行转录基因分析和基因特异验证.
主要成果:
- 鉴定出L9的四个不同的亚群. 酸性适应后.
- 与受伤或总人口相比,可活的亚群体表现出明显更高的酸耐受性.
- 五个基因被差异地表达;bglG在活跃细胞中被上调,在受伤细胞中被下调,在ATR异质性中发挥关键作用,可能是通过hsp20激活.
结论:
- 这项研究阐明了L. paracasei L9.的酸耐受反应 (ATR) 的异质性机制.
- 基因bglG被确定为ATR诱导异质性的关键调节者.
- 这些发现有助于理解和潜在地改善L. paracasei L9在工业和益生菌应用中的耐酸性.
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