IQF DiUb Technology
LifeSensors’ diubiquitin substrates represent a new class of substrates for the continuous fluorescent measurement of true isopeptidase activity. The C-terminus of wild-type ubiquitin is conjugated via an isopeptide bond to lysine 11, 48, or 63 of a second ubiquitin molecule with the resultant diubiquitin forming an internally quenched fluorescent FRET pair (IQF). Each ubiquitin is labeled with a single molecule of either a fluorescent reporter (i.e. TAMRA) or a highly efficient quenching dye. Cleavage of the IQF DiUb by deubiquitylases leads to separation of the fluorophore from quencher and subsequent increase in observed fluorescence. The ubiquitin-TAMRA reference standard can be used to optimize and calibrate the performance of individual plate readers (or fluorometers) for measurement of the rates of hydrolysis of our IQF-DiUb by DUBs.
|Molecular Weight||9,161 Da|
|Formulation||50 mM Sodium MES, pH 6.0|