Current parent of 'ubiquitin-like protein transferase activity' (GO:0019787) is 'transferase activity' (GO:0016740) = EC:2.-.-.- But I notice that all the EC numbers relating to 'ubiquitin-like protein transferase activity' (either E2s or E3s) have a EC:2.3.2.- prefix: 2.3.2.23 E2 ...