A list of KEGG enzymatic reactions given as trivial names and their EC numbers was downloaded from (accessed 2023-07-24) amounting to 20k reactions. The reactions were then passed through the EnzymeMap workflow, leading to 10k entries where a full 4-digit EC number was specified and all names could be resolved (after step 2). 7.1k entries had at least one possible balanced reaction SMILES. After step 6, 8.0k reactions (including reversed and suggested reactions, thus more than the initial 7.1k mapped reactions) were obtained, out of which 6.6k reactions were unique disregarding the EC number. MetaCyc version 27.0 was obtained from www.biocyc.org, Copyright SRI International 2022. The 18k atom mapped SMILES strings distributed with MetaCyc did not include cofactors and were partially not balanced, so that we cross-linked the distributed atom mapped SMILES with the unmapped MetaCyc reactions to add missing molecules and cofactors. Only entries with a full 4-digit EC class and not leading to an error upon loading into RDKit were retained, amounting to 7.0k reactions. The resulting reactions (balanced SMILES strings) were then passed to the EnzymeMap workflow skipping steps 1-3. After step 6, 4.6k reactions (including reversed and suggested reactions) were obtained, out of which 4.5k reactions were unique disregarding the EC number.