微生物催化GABA和提拉胺与胆汁酸的结合
Michael W Mullowney1, Aretha Fiebig2, Matthew K Schnizlein2
1Duchossois Family Institute, University of Chicago , Chicago, Illinois, USA.
Journal of bacteriology
|January 4, 2024
概括
研究人员发现,肠道细菌可以将胆汁酸 (BAs) 与神经活性氨基酸 (如氨酸 (GABA) 和胺) 结合在一起. 这些新型BA-GABA和BA- tyramine胺基存在于人体肠道中,它们的水平在炎症和抗生素治疗期间会发生变化.
科学领域:
- 微生物学 微生物学
- 代谢学 代谢学 代谢学
- 胃肠病学 胃肠病学
背景情况:
- 胆汁酸 (BAs) 是关键的胆固醇衍生物,参与消化,营养吸收和宿主微生物相互作用.
- 肠道细菌通过酶来修改BA,这有助于它们的化学多样性.
- 之前的研究重点是细菌对氨基酸与BA的结合,因此对其他氨基酸类的结合尚未探索.
研究的目的:
- 调查细菌是否可以将胆汁酸与标准氨基酸以外的氨基酸类结合在一起.
- 确定能够将神经活性氨基,特别是氨酸 (GABA) 和胺结合为胆酸的细菌物种.
- 确定这些新型胆汁酸结合物的存在和动态在人类肠道中,特别是在炎症条件的背景下.
主要方法:
- 从人类肠道样本中分离和表征细菌菌株,包括J袋.
- 在体外分析细菌与脱氧胆酸和神经活性胺 (GABA,胺) 的结合能力.
- 纵向对人类J-袋的含量进行代谢分析,并对人类便样本进行分析,以识别和量化胆酸胺.
主要成果:
- 鉴定出 *Bacteroides fragilis* 菌株 P207 能够将GABA 和胺与脱氧醇酸结合.
- 发现了各种各样的人类肠道细菌物种,可以将GABA和 tyramine 与初级和二级胆汁酸结合起来.
- 在人类便样本中检测到各种胆汁酸-GABA和胆汁酸-胺胺胺.
- 观察到二次胆汁酸水平的显著变化和BA-GABA胺基的变化概况在患有性结肠炎囊的患者中.
- 发现抗生素治疗毛囊炎导致J袋内大多数BA胺的显着减少.
结论:
- 扩大了已知的细菌胆酸修饰的知识库,包括与GABA和胺的结合.
- 证明了人类肠道中新型胆汁酸-GABA和胆汁酸-提拉胺合物的存在.
- 突出了肠道炎症和抗生素治疗期间这些结合物的动态变化,表明它们在宿主微生物生理学中的潜在作用.
- 建议这些神经活性氨基结合胆酸可能会影响宿主和微生物受体介导机制,并通过肠肝循环影响宿主生理.
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