Fig. 2

Quantitative analysis of the human gut archaea. The archaeal 16S rRNA gene copy number was quantified from faecal samples of Korean subjects using real-time quantitative PCR (n = 150, three technical replicates). Values were normalised to the abundance of the archaeal + bacterial 16S rRNA genes and are presented as relative amounts. The amount of the archaeal + bacterial 16S rRNA genes in each sample was arbitrarily considered 100. Colours of each bar graph represent the relative abundance from the archaeal 16S rRNA gene metataxonomic data. The dotted line represents the adjusted value of the gut archaeal abundance by the 16S rRNA gene copy number per genome (a mean of 1.7 and 5.0 16S rRNA genes per archaeal and bacterial genome, respectively)