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细菌吸血主义通过出租车传递给血清
bioRxiv : the preprint server for biology
|July 18, 2023
概括
肠杆菌细菌通过L-胺化学反应被吸引到人体血清中. 这种"细菌吸血"有助于它们殖民出血部位,并可能解释它们引起血液感染的倾向.
科学领域:
- 微生物学 微生物学
- 分子生物学分子生物学
- 病变的发生和发病.
背景情况:
- 肠杆菌在炎症性肠病患者中引起胃肠道出血,败血症和死亡.
- 肠道细菌进入血液的机制尚不清楚.
- 这些细菌经常与败血症和血液感染有关.
研究的目的:
- 研究细菌对人体血清的吸引力.
- 确定血清出租车中涉及的化学吸引剂和受体.
- 了解血清化疗在Enterobacteriaceae病原发生中的作用.
主要方法:
- 使用微流体装置模拟胃肠道出血.
- 测试了细菌对人体血清的吸引力.
- 确定了L-氨酸和Tsr化学受体在化学吸引中的作用.
- 沙门氏菌Typhimurium Tsr与L-氨酸结合的溶解的晶体结构.
- 绘制了 Tsr 化学受体的遗传分布图.
主要成果:
- 肠道细菌 (Salmonella,大肠杆菌,Citrobacter koseri) 的临床分离物迅速被吸引到人类血清中.
- 氨酸是一种主要的化学吸引剂,被Tsr受体识别.
- 晶体结构揭示了Tsr.中保存的L-氨酸识别图案.
- Tsr 在肠杆菌和血液病原体中广泛存在.
- 肠杆菌利用血清进行生长,而Tsr介导的化学反应为病变殖民提供了竞争优势.
结论:
- 肠杆菌表现出"细菌吸血主义" - - 向血清的吸血,出血性病变的殖民化和营养消耗.
- 通过Tsr向L-氨酸的化学反应是Enterobacteriaceae进入血液的关键机制.
- 这种行为可能解释了Enterobacteriaceae导致败血症的倾向.
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