细菌体的代谢活性随着多糖的分子量下降而降低
Jeremy P H Wong1,2, Noémie Chillier1, Michaela Fischer-Stettler3
1Institute of Bioengineering and Global Health Institute, School of Life Sciences, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.
mBio
|February 20, 2024
概括
细菌的多糖利用,包括Bacteroides thetaiotaomicron的德克斯,受到分子重量的影响. 较大的多糖体会降低生长速度,影响肠道微生物群体的组成,并可能告知精确的前生物设计.
科学领域:
- 微生物新陈代谢和多糖的利用.
- 肠道微生物群的组成和功能.
- 酶动力学和基质特异性
背景情况:
- 人体肠道细菌,如 Bacteroides thetaiotaomicron (Bt),拥有大量的多糖利用位点 (PUL) 用于碳水化合物发酵.
- 虽然众所周知,PULs针对特定的多糖,但多糖分子量对其利用的影响还未得到充分研究.
- 食纤维的复杂性会影响微生物的新陈代谢和宿主健康.
研究的目的:
- 为了研究多糖的分子量如何影响粉利用系统 (Sus) 类似系统在 Bacteroides thetaiotaomicron中的功能.
- 阐明依赖于大小的右代谢对细菌生长和社区动态的影响.
- 探索基于多糖特性设计新型精密益生菌的潜力.
主要方法:
- 评估了使用不同分子量德克斯的 Bacteroides thetaiotaomicron 的生长速度和滞后时间.
- 描述了关键的甘酸酸酶 (GHs) 的酶活性,特别是BT3087和BT3088,参与了德克斯降解.
- 分析了 Bacteroides thetaiotaomicron 的代谢输出及其对 Bacteroides fragilis 的合成微生物群落的影响.
主要成果:
- 细菌菌体的thetaiotaomicron生长速度下降,延迟时间随着德克斯分子量增加而增加.
- 鉴定出乳酶BT3087 (GH家族66) 和BT3088是依赖大小的乳代谢中的关键酶.
- 多糖体大小依赖的新陈代谢调节了 Bacteroides thetaiotaomicron 的代谢输出,改变了生产者-消费者社区的组成.
结论:
- 在 Bacteroides thetaiotaomicron 中,Sus-like 系统的活性和效率受到多糖化合物分子重量的显著影响.
- 肠道微生物对多糖的取决于大小的代谢会影响微生物群落的结构和多样性.
- 了解多糖体的尺寸依赖利用,可以了解微生物生态和制定有针对性的营养干预措施.
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