ABSTRACT

The Gram-negative, strictly anaerobic A. muciniphila is a relatively prominent member of the human gut microbiota, where it constitutes 0.1-3% of the total bacterial gut flora. As the name indicates, it is

14.1 Verrucomicrobia .................................................................................... 243 14.1.1 Akkermansia ................................................................................ 243

14.1.1.1 Impact on the host ...................................................... 243 14.1.1.2 Characteristics of the agent ...................................... 244

14.2 Deferribacteres ...................................................................................... 244 14.2.1 Mucispirillum schaedleri ............................................................. 244

14.2.1.1 Impact on the host ...................................................... 244 14.2.1.2 Characteristics of the agent ...................................... 245

14.3 Fusobacteria ........................................................................................... 245 14.3.1 Fusobacterium necrophorum ....................................................... 245

14.3.1.1 Impact on the host ...................................................... 245 14.3.1.2 Characteristics of the agent ...................................... 246

14.3.2 Streptobacillus moniliformis ........................................................ 247 14.3.2.1 Impact on the host ...................................................... 247 14.3.2.2 Characteristics of the agent ...................................... 248

14.4 Candidate phylum TM7 ....................................................................... 248 References ........................................................................................................ 249

closely associated with the gut mucus layer, where it feeds on mucin.5 Monocolonization of germ-free mice with A. muciniphila has shown that it influences mucosal immune response6; in several studies, Akkermansia has been found to be negatively correlated with diseases such as type 1 diabetes (mice and humans), ulcerative colitis (humans), and autism (children) and seems to offer protection against metabolic disorders associated with diet-induced obesity (mice).7-11 In contrast it seems to be positively correlated to the development of colon cancer in mice induced with azoxymethan.12 Treatment with vancomycin has been found to propagate A. muciniphila in the gut of mice, leading to a gut microbiota dominated by this bacterium.8 Also, feeding with xylooligosaccharides has been found to propagate A. muciniphila in mice.13