响应调节器FpsR控制了Ligilactobacillus ruminis中的鞭毛-皮利过渡和粘膜殖民
Aya Misaki1, Shunya Suzuki2, Shintaro Maeno3
1Department of Agricultural Chemistry, Tokyo University of Agriculture, Tokyo, Japan.
Gut microbes
|December 4, 2025
概括
菌的鞭毛形成是由FpsR调节的,FpsR是一个控制运动和殖民的新型开关. 这一发现揭示了人类肠道环境中的细菌适应.
科学领域:
- 微生物学 微生物学
- 细菌遗传学 细菌遗传学
- 宿主-微生物相互作用
背景情况:
- 乳酸细菌Ligilactobacillus ruminis具有鞭毛基因,但在人类菌株中没有观察到鞭毛.
- 在L. ruminis中控制鞭毛表达的调节机制仍然未被描述.
研究的目的:
- 调查L. ruminis. 鞭毛形成和运动性的遗传基础.
- 确定控制鞭毛基因表达的调节因素及其对细菌殖民和宿主相互作用的影响.
主要方法:
- 一种L. ruminis的运动性获得突变体ATCC 25644.的隔离和特征.
- 全基因组测序以确定突变者的遗传变化.
- 功能补充测试以确定关键的调节基因.
- 在小鼠模型中评估毛囊产量,粘附性,酸/胆耐受性和肠道殖民.
主要成果:
- 在酸性条件下,一种获得运动性的突变体表现出完全的鞭和化学毒性.
- 确定了大约35kb的删除,包括响应调节器FpsR (鞭-化切换调节器).
- FpsR充当一个开关,抑制鞭和促进 pili; 它的缺席导致粘附性降低,增加对酸/胆的敏感性,并导致肠道殖民失败.
- 来自移动菌株的鞭毛素在体外诱导了亲炎性反应,但在体内由于殖民失败而不是.
结论:
- FpsR是一种新型遗传调节剂,协调L. ruminis.中的运动性和粘膜殖民.
- 通过FpsR使旗沉默对于这种人类共生细菌的共生相互作用和肠道殖民至关重要.
- 这项研究提供了对肠道环境中细菌鞭毛的调节的见解,以维持宿主-微生物共生.
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