Fig. 4

a Sensitivity testing of the Enterobacteriaceae database. Randomly fragmented 16S rRNA genes specific to S. enterica were compared to the Enterobacteriaceae database using BLASTn. Fragment sizes ranged from 100 to 500 bp and errors were randomly introduced at rates ranging from 0 to 1 %. The S. enterica non-exclusive plot (green) represents the percentage of hits to Salmonella and other Enterobacteriaceae. The S. enterica diagnostic plot (purple) represents the percentage of hits exclusive to Salmonella (left axis). The false negative rate plot (blue) represents the percentage of 16S fragments without a Salmonella best alignment (right axis). b Specificity testing of the Enterobacteriaceae database. 16S rRNA fragments specific to E. coli were randomly fragmented to sizes ranging from 100 to 500 bp and random errors were introduced. Fragments were searched against the Enterobacteriaceae database using BLASTn. c Validation of the Enterobacteriaceae database using BLASTn analysis of raw Illumina MiSeq reads from 105 S. enterica 16S rRNA genes to the EnteroDB. The S. enterica non-exclusive plot (green) represents the percentage of hits to Salmonella and other Enterobacteriaceae. The S. enterica diagnostic plot (purple) represents the percentage of hits exclusive to Salmonella (left axis). The false negative rate plot (blue) represents the percentage of 16S rRNA fragments without a Salmonella best alignment (right axis)