MetaCyc

The MetaCyc database contains extensive information on metabolic pathways and enzymes from many organisms. MetaCyc stores experimentally determined metabolic pathways.

MetaCyc can serve as a reference data set for computationally predicting the metabolic pathways of organisms from their sequenced genomes, and has been used to perform pathway predictions for hundreds of organisms, including those in the BioCyc Database Collection.

MetaCyc contains extensive data on individual enzymes, describing their subunit structure, cofactors, activators and inhibitors, substrate specificity, and, in some cases, kinetic constants. It also provides commentary and literature references.