Chemical Substances and Reactions

KEGG LIGAND contains our knowledge on the universe of chemical substances and reactions that are relevant to life. It is a composite database consisting of COMPOUND, GLYCAN, REACTION, RCLASS, and ENZYME databases, whose entries are identified by C, G, R, RC, and EC numbers, respectively. ENZYME is derived from the IUBMB/IUPAC Enzyme Nomenclature with annotation of reactions and sequences. All the other databases are internally developed and maintained.
Database Identifier Content Specialized
entry point
LIGAND COMPOUND C number Chemical compound structures KEGG COMPOUND
GLYCAN G number Glycan structures KEGG GLYCAN
REACTION R number Biochemical reactions KEGG REACTION
RCLASS RC number Reaction class
ENZYME EC number Enzyme nomenclature

LIGAND Relational Database

The primary database of KEGG LIGAND is a relational database with the KegDraw interface, which is used to generated the secondary (flat file) database for DBGET. A read-only copy of the LIGAND relational database is made publicly accessible.

blue Search COMPOUND
blue Search GLYCAN
blue Search REACTION

Chemical Structure Search

blue Search similar compound structures
SIMCOMP:maximal common subgraph search -- a portion of the query compound is optimally matched to a portion of the database compound [references]
SUBCOMP:isomorphic subgraph search -- the query compound is fully matched to a portion of the database compound (substructure match) or a portion of the query compound is fully matched to the database compound (superstructure match)
blue Search similar glycan structures
KCaM: local or global search for matching tree structures [reference]
blue Download chemical structure drawing tool
KegDraw:Java application for drawing chemical compound structures and glycan structures with the capabilities to search against the KEGG databases

Reaction Search and Prediction

blue Assign EC number from chemical structures
E-zyme:automatic assignment of EC numbers (at the sub-subclass level) for a given set of substrate-product pairs [references]
blue Predict and search reaction pathways
PathPred:prediction of biodegradation and biosynthetic pathways by matching against known subsets of RDM patterns [reference]
PathComp:search for possible reaction paths between two compounds based on the information of reactions, enzymes, or enzyme genes
PathSearch:search for similar reaction subpathways for a given set of R numbers, RP numbers, or RC numbers

Last updated: September 20, 2016
KEGG GenomeNet Kanehisa Laboratories