This is the category metabolic networks. It contains 8 networks. Metabolic networks model metabolic pathways, in which nodes a chemical substances and edges are often directed and represents chemical interactions. A subset are protein–protein interaction networks (PPI), in which nodes are proteins, and which are usually undirected.
| Name | Attributes | n | m | Node meaning | Edge meaning |
| PDZBase | | 212 | 244 | Protein | Interaction |
| Caenorhabditis elegans (metabolic) | | 453 | 2,025 | Substrate | Metabolic reaction |
| Yeast | | 1,870 | 2,277 | Protein | Interaction |
| Caenorhabditis elegans | | 453 | 4,596 | Metabolite | Interaction |
| Human proteins (Stelzl) | | 1,706 | 6,207 | Protein | Interaction |
| Human proteins (Vidal) | | 3,133 | 6,726 | Protein | Interaction |
| Human proteins (Figeys) | | 2,239 | 6,452 | Protein | Interaction |
| Reactome | | 6,327 | 147,547 | Protein | Interaction |