福克斯感应调节了细菌肠道殖民的情况
Alline R Pacheco1, Meredith M Curtis, Jennifer M Ritchie
1Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9048, USA.
Nature
|November 20, 2012
概括
肠道出血性大肠杆菌 (EHEC) 使用肠道中丰富的糖分fucose来控制其毒性. 这种糖感应系统,FusKR,对于EHEC殖民和哺乳动物肠道中的致病性至关重要.
科学领域:
- 微生物学 微生物学
- 分子生物学分子生物学
- 胃肠病学 胃肠病学
背景情况:
- 哺乳动物的肠道是一个具有竞争力的微生物环境.
- 病原体殖民需要营养清理,信号传感和毒性基因调节.
- 肠道出血性大肠杆菌 (EHEC) 使用跨王国信号进行毒性.
研究的目的:
- 在EHEC中识别新的化学传感系统.
- 调查福克斯感应在EHEC毒性和殖民化中的作用.
- 阐明肠道中的微生物群和EHEC之间的相互作用.
主要方法:
- 一个新型的两组件系统FusKR (FusK传感器激酶,FusR响应调节器) 的表征.
- 对FusK的fucose感应能力的分析.
- 评估FusKR系统对EHEC肠道殖民化的要求.
- 调查 Bacteroides thetaiotaomicron 在通过 fucose 激活 EHEC 毒性的作用.
主要成果:
- 在EHEC中发现了一种新的fucose感应双组件系统FusKR.
- FusKR控制毒性和代谢基因的表达.
- 对于哺乳动物肠道的强大的EHEC殖民,FusKR系统至关重要.
- 细菌菌体thetaiotaomicron从粘素中切割fucose,激活EHEC的FusKR系统并调节毒性基因表达.
结论:
- EHEC使用FusKR系统来感知和利用肠道中易于获得的营养素fucose.
- 微生物群驱动的粉可用性会影响EHEC的致病性和代谢.
- 这项研究揭示了EHEC通过感知由共生细菌提供的宿主衍生信号来适应宿主环境的机制.
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