News Release

November 29, 2011

Contact: Geoffrey Schwartz Phone: +1 951-514-4223 Email: geoffrey.schwartz@merckgroup.com

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

November 29, 2011, Billerica, MA — EMD Millipore, the Life Science division of Merck KGaA* of 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-pending fluorescently-coupled enzyme assay for nicotinamide degradation to permit the use of native NAD+ substrate and flexibility with peptide/protein acceptor substrates.

For more information on the PARP1 Enzyme Assay kit, please visit www.millipore.com/catalogue/item/17-10149.

About PARP
Poly(ADP-ribose) (PAR) is a polymer of ADP-ribose present in the nucleus in a free state or as a post-translational modification on glutamate residues on a number of substrates. Synthesis and degradation of PAR are highly regulated, and its presence mediates DNA repair, chromatin structure, cell cycle, and cell death. A family of poly(ADP-ribose) polymerases (PARPs) catalyzes the addition of ADP-ribose moieties onto substrate proteins via cleavage of NAD+ and liberation of nicotinamide. PARP1 plays a key role in DNA damage repair. PARP2 overlaps functionally with PARP1 in DNA damage repair, but PARP2 plays a distinct role from PARP1 in development of spermatogonia, adipose tissue, and thymus tissue.

A number of PARP1 inhibitors have been developed to block repair of chemotherapeutic agent-induced genotoxic damage, and thereby potentiate the cytotoxic effect of chemotherapeutics in cancer patients. Inhibition of PARP1 appears to be particularly efficacious in conjunction with chemotherapeutics on cancer cells harboring mutations in components of homologous recombination DNA repair pathways, primarily BRCA1, and BRCA2. These mutations can lead to an increased risk for breast cancer. PARP inhibitors are also being evaluated in clinical trials.

About EMD Millipore
EMD Millipore is the Life Science division of Merck KGaA of Germany and offers a broad range of innovative, performance products, services and business relationships that enable our customers' success in research, development and production of biotech and pharmaceutical drug therapies. Through dedicated collaboration on new scientific and engineering insights, and as one of the top three R&D investors in the Life Science Tools industry, EMD Millipore serves as a strategic partner to customers and helps advance the promise of life science.

Headquartered in Billerica, Massachusetts, the division has around 10,000 employees, operations in 67 countries an 2010 revenues of $2.2 billion. EMD Millipore is known as Merck Millipore outside of the U.S. and Canada.

Note: Merck KGaA or Merck shall mean Merck KGaA, Darmstadt, Germany