InterPro domain: IPR030661

The SUMO activating enzyme E1 enzyme facilitates conjugation of ubiquitin and ubiquitin-like proteins through adenylation, thioester transfer within E1, and thioester transfer from E1 to E2 conjugating proteins [ 1 ]. This entry represents a subunit of the E1 enzyme, including Uba2 from yeasts [ 2 ] and its homologue, SAE2 from animals [ 3 ]. E1 enzymes mediates ATP-dependent activation of SUMO proteins followed by formation of a thioester bond between a SUMO protein and a conserved active site cysteine residue on UBA2/SAE2 [ 4 , 5 ].

1. Structures of the SUMO E1 provide mechanistic insights into SUMO activation and E2 recruitment to E1. EMBO J. 24, 439-51
2. An essential yeast gene encoding a homolog of ubiquitin-activating enzyme. J. Biol. Chem. 270, 18099-109
3. Expression and regulation of the mammalian SUMO-1 E1 enzyme. FASEB J. 15, 1825-7
4. Active site remodelling accompanies thioester bond formation in the SUMO E1. Nature 463, 906-12
5. The intrinsic affinity between E2 and the Cys domain of E1 in ubiquitin-like modifications. Mol. Cell 27, 228-37