Figure 3. The number of proteins matched to nitrogen metabolism functions among multiple metagenome studies.
a. marine metagenomes and b. soil metagenomes. To facilitate comparison among studies, the number of matches is normalized to the ‘discovery rate’ for proteins in the dataset (number of protein matches per 100 fragments). For a. the marine metagenomes are as in Table 2, while b. uses Midwestern soil metagenomes (MG-RAST ids 4441091.3, 4442657.3, 4442656.3, 4442658.3, 4442659.3, 4441281.3, respectively).
