SUMO1 (human) (rec.) (Rhodamine 110)

SUMO1 is a ubiquitin-like protein that can be covalently attached to proteins as a monomer or a lysine-linked polymer. Covalent attachment via an isopeptide bond to its substrates requires prior activation by the E1 complex SAE1-SAE2 and linkage to the E2 enzyme UBE2I and can be promoted by E3 ligases such as PIAS1-4, RANBP2 or CBX4. This post-translational modification on lysine residues of proteins plays a crucial role in a number of cellular processes such as nuclear transport, DNA replication and repair, mitosis and signal transduction. This SUMO1 substrate is C-terminally derivatized with a bis-Gly-Rhodamine 110 fluorophore. The bis-Gly-Rh110 is quenched until the amide bond between the C-terminal glycine and the bis-Gly-Rh110 compound is hydrolyzed to mono-Gly-Rhodamine 110. The efficiency of quenching combined with the powerful signal upon hydrolysis yields a reagent with unparalleled signal-to-background. SUMO1-Rh110 can be used to study the deSUMOylating activity of hydrolases SENP1 and SENP2, or other deSUMOylating enzymes. The substrate activity of SUMO1-Rhodamine 110 was determined by measuring the SENP1 catalyzed release of unquenched mono-Gly-Rh110.