Figure 3

Taxonomic profiles of metagenomes of lignocellulosic (blue)- and non-lignocellulosic (red)-degrading sources. A) The relative taxonomic distributions of bacterial phyla in different metagenomic datasets. Each bar represents the percentage of total reads. The numbers within the bars indicate numbers of unique genes that reads from metagenomic libraries mapped to. Proteobacteria dominate almost all metagenomic communities, except for human gut, mouse gut, and wallaby gut, which are dominated by Firmicutes, and termite gut by Spirochaetes. B) Principal component analysis (PCA) of bacterial diversity profiles (left) and metagenome profiles (right). The bacteria of many phyla are found in highly overlapping environments, except for Firmicutes and Spirochaetes, which are predominantly present in mammal and termite guts; this explains why their profiles are not clustered with other metagenomes in the PCA plot.