The Transcreener ADP2 Assay uses a highly selective antibody and far-red fluorescent tracer to directly detect ADP produced by any ADP-producing enzyme (i.e. kinases, ATPases, helicases, carboxylases, nucleotidases, and chaperonins). The direct detection method offers a unique approach that simplifies the protocol (no coupling enzyme needed) and reduces compound interference. The assay can be used to:
- Measure activity of any ADP-producing enzyme
- Screen compound libraries for modulators
- Quantify inhibitor potency
- Inhibitor selectivity profiling
- Measure drug-target residence time
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Image Credit: BellBrook Labs
Targets Validated with the Transcreener ADP2 Assay
BellBrook Labs develops complete assay solutions for tougher enzyme targets that are difficult to source enzymes and/or develop assays for (so you can focus on optimizing your lead molecules). Currently, they have assay solutions for the ADP-producing enzyme targets listed in the table below. Click on a target to learn more.
Source: BellBrook Labs
Features
- Direct detection of unlabeled ADP
- Easy to use and HTS-ready
- Highly sensitive assay reduces enzyme usage
- Generic nature makes it compatible with any ADP-producing enzyme
- Robust Assay Z' > 0.7 under initial velocity conditions
- Far-red fluorescent readouts minimize compound interference
- A safe, non-radioactive method
- Use with ATP concentrations from 0.1 to 1000 µM
- Available in FP, FI, or TR-FRET readouts
- Can be used in continuous or endpoint mode
Example Data using MAPK1 Kinase
Robust Assay Ready to Scale for HTS
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Z' = 0.90. Robust data is neccessary to confirm the assay is well-suited for screening large compound libraries in a high-throughput format.
Image Credit: BellBrook Labs
Detection of ADP Under Initial Velocity Conditions
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MAPK1 enzyme titration using Transcreener ADP2 Assay with FP readout. The enzyme buffer included 20 mM Tris pH 7.5, 10 mM MgCl2, 1 mM DTT, and 0.01% Tween-20. The detection mix included 1X Stop and Detect Buffer B, 6.4 μg/mL ADP2 Antibody, and 4 nM ADP2 Tracer.
Image Credit: BellBrook Labs
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MAPK1 linear response. The assay shows linearity when raw data is converted to ADP using a standard curve.
Image Credit: BellBrook Labs
Screen Compound Libraries & Perform Dose Responses
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MAPK1 dose response with compound staurosporine using Transcreener ADP2 FP Assay. IC50 (Staurosporine)= 0.77 μM.
Image Credit: BellBrook Labs
Lead Discovery Services
BellBrook Labs also offers lead discovery services for scientists who want to advance their program but don't want to bring a biochemical assay in-house. Their services feature customizable assay conditions, quick turnaround times, and direct collaboration with a BellBrook scientist. Lead discovery services can include:
- Inhibitor Screening
- Inhibitor Potency Profiling
- Inhibitor Selectivity Profiling
- Residence Time Measurements
- Mechanism of Action Studies
- Triage Non-Stoichiometric Inhibitors
- Compound-Target Binding with Thermal Shift Assays