Article 3 community structure 3 microbial diversity nonhuman 3 population abundance Faecalibacterium prausnitzii 2 Metagenomics 2 Prevotella 2 Selenomonas 2 adult 2 amino acid metabolism 2 bacterial metabolism 2 bacterium 2 carbohydrate metabolism 2 controlled study 2 disease association 2 fatty acid synthesis 2 feces analysis 2 female 2 fermentation 2 human 2 intestine flora 2 male 2 metagenomics 2 microbial community 2 operational taxonomic unit 2 species diversity 2 1,3 propanediol 1 Actinomyces 1 Actinomyces dentalis 1