[Dictionary] KEGG (Kyoto Encyclopedia of Genes and Genomes)

A manually curated, integrated database resource -- initiated in 1995 by Minoru Kanehisa at Kyoto University's Institute for Chemical Research and maintained by the Kanehisa Laboratories -- that represents biological systems as a computable network linking genes, proteins, small molecules and reactions to the higher-level pathways and functions they participate in. Organized into linked component databases: PATHWAY (manually drawn pathway maps), MODULE (functional gene-set units), BRITE (hierarchical functional classifications), GENES/ORTHOLOGY (gene and ortholog annotation across sequenced genomes), and COMPOUND/REACTION/ENZYME (chemical and enzymatic data). Free to browse via the website; bulk FTP downloads have required a paid subscription since July 2011, a funding-driven access split worth noting explicitly in a data management plan rather than assuming KEGG data is unconditionally free to redistribute.