拟杆菌属微生物对多糖的利用调控机制
Title：
Navigating the Gut Buffet: Control of Polysaccharide Utilization in Bacteroides spp.
Abstract：
Bacteroides spp. are members of the human gut microbiota that confer myriad benefits on their hosts. Among them is the provision of energy from otherwise indigestible polysaccharides comprising part of the host diet, lining the intestinal mucosal layer, and decorating the surface of other microbes. Bacteroides spp. devote ∼20% of their genomes to the transport and breakdown of a wide variety of polysaccharides, and to the regulation of these processes. Bacteroides spp. rely on different families of transcriptional regulators to ensure that carbohydrate utilization genes are expressed under specific conditions. The regulators and mechanisms controlling carbohydrate utilization are often unique to these gut-dwelling bacteria, and do not conform to those of model organisms.
All Authors：
Nathan D Schwalm III, Eduardo A Groisman
First Authors：
Nathan D Schwalm III
Correspondence：
Eduardo A Groisman
内容要点：
1、拟杆菌属分解宿主膳食、小肠粘膜层和其他细菌表面的复合多糖；
2、多种跨膜调控蛋白控制多糖利用基因的转录，拟杆菌属贡献20%基因组进行多种多糖的转运和分解，并调控其加工过程，这些基因成簇分布在基因组上的特定区域，成为多糖利用位点（PUL）；
3、PUL调控因子包括胞外功能σ因子（ECF-σ）/抗-σ因子、SusR-型、双组分杂交系统（HTCS）；
4、多层次多种调控促进优先利用多糖，多糖分解的整体调控因子是拟杆菌在哺乳动物肠道内生存所必须。