Catalysis of the transfer of FAT10 to a substrate protein via the reaction X-FAT10 + S = X + S-FAT10, where X is either an E2 or E3 enzyme, the X-FAT10 linkage is a thioester bond, and the S-FAT10 linkage is an isopeptide bond between the C-terminal glycine of FAT10 and the epsilon-amino group of lysine residues in the substrate.
E3