SAMEA14084216 ERS11687349 uncultured Bacteroidales bacterium This sample represents a Third Party Annotation (TPA) Metagenome-Assembled Genome (MAG) assembled from the metagenomic run ERR321580 of study ERP003612. EBI Generic Generic.1.0 ERC000047 2023-01-03 2023-01-03 SAMEA14084216 EBI European Bioinformatics Institute 2023-01-03T00:33:33Z 2023-01-03T00:33:33Z public ERR321580_bin.101_CONCOCT_v1.1_MAG Many fragments with little to no review of assembly other than reporting of standard assembly statistics spades_v3.11.1 Default CONCOCT v1.1 EMG broker account, EMBL-EBI 2008-01-01 98.81 CheckM 1.13 Host-associated Human Digestive system Denmark 55.676098 12.568337 metagenome-assembled genome human gut metagenome human gut metagenome We are facing a global metabolic health crisis provoked by an obesity epidemic. Here we report the human gut microbial composition in a population sample of 123 non-obese and 169 obese Danish individuals. We find two groups of individuals that differ by the number of gut microbial genes and thus gut bacterial richness. They harbour known and previously unknown bacterial species at different proportions; individuals with a low bacterial richness (23% of the population) are characterized by more marked overall adiposity, insulin resistance and dyslipidaemia and a more pronounced inflammatory phenotype when compared with high bacterial richness individuals. The obese individuals among the former also gain more weight over time. Only a few bacterial species are sufficient to distinguish between individuals with high and low bacterial richness, and even between lean and obese. Our classifications based on variation in the gut microbiome identify subsets of individuals in the general white adult population who may be at increased risk of progressing to adiposity-associated co-morbidities. SAMEA2158769 ERR321580_bin.101_CONCOCT_v1.1_MAG uncultured Bacteroidales bacterium Illumina HiSeq 2000 multi-marker approach