【背景资料】:SUMOylation of substrate proteins takes place in a manner analogous to that of the ubiquitin conjugation system, utilising E1, E2 and E3 enzymes in an ATP dependent process and often requires a short sequence containing the consensus Ψ-K-X-D/E (where lysine is the modified amino acid, Ψ is a large hydrophobic residue and X is any amino acid residue) on the substrate protein for protein SUMO modification to occur. Whilst the specific roles of the three SUMO isoforms have not been fully elucidated they have been shown to regulate distinct mitotic processes in mammalian cells. In addition SUMO2 and SUMO3 can form homogenous and mixed chains, with SUMO1, which does not contain the internal SUMO consensus sites (K11) found in SUMO2 and SUMO3, thought to terminate mixed polySUMO chains. Recombinant human SUMO1 protein expressed with a N-terminal His-tag. Protein has utility in SUMOylation reactions and SUMO1 binding assays.