FIG. 7.

Screenshot (at left) from the IMG/M database (91) showing one implementation of gene-centric analysis available through this system. Four PFAM families involved in cellulose hydrolysis are shown in columns color coded to match the pathway schematic to the right. The relative representation of these families in 12 metagenomic data sets (rows) is shown as fractions normalized for data set size. Overrepresented families are further highlighted by color: bisque, moderately overrepresented; yellow, highly overrepresented. This figure shows that termite hindgut followed by human gut samples have the greatest overrepresentation of genes involved in cellulose hydrolysis and, indeed, are the only communities of the compared data sets that appear to have the enzymatic potential to break down cellulose. It also shows that one whale fall sample, a soil sample from the drainage path of a silage storage bunker, and one laboratory-scale phosphorus-removing sludge sample are moderately overrepresented in genes for processing the dimer cellobiose. (Image courtesy of Falk Warnecke.)