双歧杆菌的最新研究进展|微生态前沿

一、为什么双歧杆菌代谢糖类的能力更强？



   

01

    

双歧杆菌是大多数动物肠道中定植的主要菌种，而糖则作为肠道微生物的主要碳源，对复杂的肠道菌群施加选择压力；

    

02

    

对47个代表性的双歧杆菌进行基因组分析，发现双歧杆菌与糖代谢吸收有关的基因多于肠道其他菌群；

    

03

    

双歧杆菌多糖代谢能力被认为可以反映哺乳动物肠道可用碳的水平，转录组分析也发现双歧杆菌多糖代谢的证据；

    

04

    

这样的发现与已有的人类粪菌样品数据一致。




延伸阅读：


Bifidobacteria exhibit social behavior through carbohydrate resource sharing in the gut

Abstract:
      Bifidobacteria are common and frequently dominant members of the gut microbiota of many animals, including mammals and insects. Carbohydrates are considered key carbon sources for the gut microbiota, imposing strong selective pressure on the complex microbial consortium of the gut. Despite its importance, the genetic traits that facilitate carbohydrate utilization by gut microbiota members are still poorly characterized. Here, genome analyses of 47 representative Bifidobacterium (sub)species revealed the genes predicted to be required for the degradation and internalization of a wide range of carbohydrates, outnumbering those found in many other gut microbiota members. The glycan-degrading abilities of bifidobacteria are believed to reflect available carbon sources in the mammalian gut. Furthermore, transcriptome profiling of bifidobacterial genomes supported the involvement of various chromosomal loci in glycan metabolism. The widespread occurrence of bifidobacterial saccharolytic features is in line with metagenomic and metatranscriptomic datasets obtained from human adult/infant faecal samples, thereby supporting the notion that bifidobacteria expand the human glycobiome. This study also underscores the hypothesis of saccharidic resource sharing among bifidobacteria through species-specific metabolic specialization and cross feeding, thereby forging trophic relationships between members of the gut microbiota.

All Authors:Christian Milani,Gabriele Andrea Lugli,Sabrina Duranti,Francesca Turroni,Leonardo Mancabelli,Chiara Ferrario,Marta Mangifesta,Arancha Hevia,Alice Viappiani,Matthias Scholz,Stefania Arioli,Borja Sánchez,Jonathan Lane,Doyle V Ward,Rita Hickey,Diego Mora,Nicola Segata,Abelardo Margolles,Douwe Van Sinderen,Marco Ventura

2015-10-28Article




二、双歧杆菌如何利用多糖和喂养其他细菌？(综述)


   

01

    

双歧杆菌分解多糖的能力促进了其在哺乳动物肠道中的定殖；

    

02

    

功能基因组分析揭示，双歧杆菌的基因组中含有大量与碳水化合物代谢相关的基因，且在富含多糖的环境中表现出物种特异性的适应性；

    

03

    

 饮食中（淀粉、木聚糖等）及宿主产生（母乳聚糖、黏蛋白等）的多糖，是塑造双歧杆菌基因组的潜在进化动力；

    

04

    

 双歧杆菌具有互养活性，可将复杂的多糖水解后产生较为简单的多糖，后者可被其它菌种/菌株利用。






延伸阅读：


Glycan Utilization and Cross-Feeding Activities by Bifidobacteria

Abstract:
      Bifidobacteria represent one of the first colonizers of the mammalian gut, where such colonization is facilitated by their saccharolytic capabilities. Genomic analyses of bifidobacteria have revealed intriguing genetic strategies employed by these bacteria to access a variety of dietary and host-produced glycans. Bifidobacterial genome evolution therefore represents a fascinating example of how their chromosomes were molded to contain a large number of genes involved in carbohydrate metabolism. One of the reasons as to why bifidobacteria are such dominant and prevalent members of the (early) microbiota is that they may access glycans in the gut through mutualistic cross-feeding or resource-sharing activities, which is indicative of 'social behavior' among bifidobacterial strains.

First Authors:Francesca Turroni

Correspondence:Marco Ventura

All Authors:Francesca Turroni,Christian Milani,Sabrina Duranti,Jennifer Mahony,Douwe van Sinderen,Marco Ventura

2017-10-28Review