Figure 2: Predicted ORFs in the human gut microbiome.
From: A human gut microbial gene catalogue established by metagenomic sequencing

a, Number of unique genes as a function of the extent of sequencing. The gene accumulation curve corresponds to the Sobs (Mao Tau) values (number of observed genes), calculated using EstimateS21 (version 8.2.0) on randomly chosen 100 samples (due to memory limitation). b, Coverage of genes from 89 frequent gut microbial species (Supplementary Table 12). c, Number of functions captured by number of samples investigated, based on known (well characterized) orthologous groups (OGs; bottom), known plus unknown orthologous groups (including, for example, putative, predicted, conserved hypothetical functions; middle) and orthologous groups plus novel gene families (>20 proteins) recovered from the metagenome (top). Boxes denote the interquartile range (IQR) between the first and third quartiles (25th and 75th percentiles, respectively) and the line inside denotes the median. Whiskers denote the lowest and highest values within 1.5 times IQR from the first and third quartiles, respectively. Circles denote outliers beyond the whiskers.