EMD Millipore Introduces PARP1 Enzyme Activity Assay for Enhanced Detection and Sensitivity as Compared with Traditional Activity Assays
  • Enables rapid quantitation of PARP activity with more sensitivity than traditional assays
  • Enables measurement of activity and screening of PARP activators and inhibitors
  • Overcomes limitations of existing assays by using native NAD+ as a substrate

EMD Millipore, the Life Science division of Merck KGaA of Darmstadt, Germany, today announced the launch of the PARP1 Enzyme Assay for detection of poly (ADP-ribose) polymerase(PARP) activity and screening of activators and inhibitors.  PARPs catalyze the addition of ADP-ribose moieties onto substrate proteins and play a role in DNA repair, chromatin structure, cell cycle, and cell death.

The kit is a flexible, homogenous, no-wash assay for quantifying enzymatic activity.  Based on patent-pending technology, this assay employs nicotinamidase to measure nicotinamide generated upon cleavage of NAD+ during PARP-mediated poly-ADP-ribosylation of a substrate, thereby providing a direct, positive signal assessment of the activity of PARP1 and PARP2.

“The most commonly used assays for PARP activity employ biotinylated NAD+ as a substrate for PARP to incorporate biotinyl-ADP-ribose into the PAR chain on an immobilized histone substrate”, describes Haizhen Liu, Lead R&D Scientist for Assay Development.   “The quantity of incorporated biotinyl-ADP-ribose is determined with streptavidin-HRP. Disadvantages of this method are that the use of non-native NAD+ analogs as a substrate may yield different kinetics than unmodified, native NAD+, a lack of flexibility in using protein/peptide substrates, and the need for multiple time-consuming wash steps.  All of these shortcomings are address by the new PARP assay.”

The new PARP assay utilizes a novel, patent-pendingfluorescently-coupled enzyme assay for nicotinamide degradation to permit the use of native NAD+ substrate and flexibility with peptide/protein acceptor substrates.