Atg12 transferase activity APG12 ligase activity Reactome:R-HSA-5681999 APG12 conjugating enzyme activity GO:0019777 Atg12 conjugating enzyme activity Catalysis of the transfer of ATG12 from one protein to another via the reaction X-ATG12 + Y = Y-ATG12 + X, where both X-ATG12 and Y-ATG12 are covalent linkages. Atg12 ligase activity molecular_function ubiquitin-like protein transferase activity