Figure 4

Results from three different approaches to peptide spectrum matching of shotgun meta proteomics data. Spectra from NO1 (A) and NO3 (B) were identified in separate OMSSA runs using the 'synthetic metaproteome' (green), naive translation of the matched metagenome (blue) and a translated metagenomic subset (red) as search space. Combining the search results from the synthetic metagenome search and the results from the search against the translated metagenomic subset, the proposed method (Figure 3) yields the highest spectrum identification rate. As expected, most of the spectra identified using the 'synthetic metaproteome' are also identified using the translated subset.