Ringel Yehuda, Maharshak Nitsan, Ringel-Kulka Tamar, Wolber Elizabeth Ashley, Sartor R Balfour, Carroll Ian M
a Division of Gastroenterology and Hepatology; Center for Gastrointestinal Biology and Disease; University of North Carolina at Chapel Hill ; Chapel Hill , NC , USA.
Gut Microbes. 2015;6(3):173-81. doi: 10.1080/19490976.2015.1044711.
The intestinal microbiota is associated with human health and diseases. The luminal microbiota (LM) and the mucosal-associated microbiota (MAM) are 2 distinct ecosystems with different metabolic and immunological functions.
To characterize the intestinal LM and MAM in humans using high throughput sequencing of the 16S rRNA gene.
Fresh fecal samples and distal colonic mucosal biopsies collected from 24 healthy subjects before (fecal) and during (mucosa) a flexible sigmoidoscopy of an un-prepared bowel. High throughput sequencing of the 16S rRNA gene was used to characterize bacterial communities. Sequences were processed using the QIIME pipeline.
LM and MAM populations were significantly different (ANOSIM: R = 0.49, P = 0.001). The LM displayed tighter clustering compared to the MAM (average weighted UniFrac distances 0.27 ± 0.05 vs. 0.43 ± 0.09, P < 0.001, respectively), and showed higher diversity (Shannon diversity index: 4.96 ± 0.37 vs 4.14 ± 0.56, respectively, P < 0.001). The dominant phyla in the LM and MAM were significantly different: Firmicutes (41.4% vs. 29.1%, FDR < 0.0001, respectively), Bacteroidetes (20.2% vs. 26.3%, FDR < 0.05, respectively), Actinobacteria (22% vs. 12.6%, FDR < 0.0001, respectively) and Proteobacteria (9.3% vs. 19.3%, FDR < 0.0001, respectively). The abundance of 56 genera differed significantly (FDR < 0.1) between the 2 niches. All of the genera in the fecal microbiota were present in the MAM while 10 genera were found to be unique to the MAM.
The LM and MAM are distinct microbial ecosystems that differ significantly from each other in microbial diversity and composition. These two microbial niches should be investigated independently to better understand the role of the intestinal microbiota in health and disease.
肠道微生物群与人类健康和疾病相关。肠腔微生物群（LM）和黏膜相关微生物群（MAM）是两个具有不同代谢和免疫功能的独特生态系统。
通过对16S rRNA基因进行高通量测序来描述人类肠道LM和MAM的特征。
在未进行肠道准备的乙状结肠镜检查前（粪便）和检查期间（黏膜），从24名健康受试者收集新鲜粪便样本和远端结肠黏膜活检组织。使用16S rRNA基因的高通量测序来描述细菌群落特征。序列使用QIIME管道进行处理。
LM和MAM群体存在显著差异（ANOSIM：R = 0.49，P = 0.001）。与MAM相比，LM表现出更紧密的聚类（平均加权UniFrac距离分别为0.27±0.05和0.43±0.09，P < 0.001），并且具有更高的多样性（香农多样性指数：分别为4.96±0.37和4.14±0.56，P < 0.001）。LM和MAM中的优势菌门存在显著差异：厚壁菌门（分别为41.4%和29.1%，FDR < 0.0001）、拟杆菌门（分别为20.2%和26.3%，FDR < 0.05）、放线菌门（分别为22%和12.6%，FDR < 0.0001）和变形菌门（分别为9.3%和19.3%，FDR < 0.0001）。两个生态位之间56个属的丰度存在显著差异（FDR < 0.1）。粪便微生物群中的所有属均存在于MAM中，而发现有10个属是MAM特有的。
LM和MAM是不同的微生物生态系统，在微生物多样性和组成上彼此存在显著差异。应该独立研究这两个微生物生态位，以更好地了解肠道微生物群在健康和疾病中的作用。
