KEGG API
The KEGG molecular database as an API, powered by the official KEGG REST service. KEGG (the Kyoto Encyclopedia of Genes and Genomes) links genomes, chemistry and disease. Fetch any KEGG entry parsed to JSON — a metabolic compound, KEGG Orthology group (KO), enzyme (EC number), reaction, module, drug, disease, glycan, gene or pathway map; search any KEGG database by name; list a database's entries; cross-link entries between databases (a gene to its pathways, a pathway to its compounds, an enzyme to its reactions); and convert KEGG identifiers to and from outside namespaces (NCBI Gene/Protein, UniProt, ChEBI, PubChem). Ideal for systems-biology and metabolomics pipelines, enzyme and orthology mapping, drug and disease research, gene-to-pathway annotation and bioinformatics id conversion. KEGG ids are letter-prefixed (C compound, K orthology, D drug, H disease, M module, R reaction, G glycan) or organism-coded (hsa human, eco E. coli).
api.oanor.com/kegg-api