Transcreener GDP FP Assay

The Transcreener^® HTS Assay platform overcomes the need for time-consuming, one-off assay development for individual members within a group transfer enzyme family by utilizing a single set of assay reagents that detect an invariant product. The generic nature of the Transcreener^® HTS Assay platform eliminates delays involved in assay development for new HTS targets, and greatly simplifies compound and inhibitor profiling across multiple target families. Transcreener assays have been validated with major HTS instruments to determine the optimal filters and settings for maximal assay performance. Application notes with all important details are available.

The Transcreener GDP GTPase assay is a homogenous, fluorescent immunoassay that monitors the activity of GTPases along with GEF and GAP partners. The assay directly measures the amount of GDP produced in an in vitro GTPase reaction. Three available fluorescent readouts, Fluorescence polarization (FP), Fluorescence intensity (FI) and Time-resolved Forster-resonance-energy-transfer (TR-FRET), provide a safe HTS-compatible alternative to cumbersome radioassay methods and are more sensitive and less subject to interference than colorimetric phosphate detection methods. All readouts use far-red tracers to minimize compound interference and lower false-positive rates.

Transcreener® GDP FP Assay (Prod. No. BBL-3009) is a mix-and-read fluorescent GTPase assay to follow the progress of any enzyme that produces GDP, including monomeric small G proteins, such as CDC42, and Gα subunits of heterotrimeric G proteins, such as Gαi1. It can be used for screening GTPases, fucosyltransferase or mannosyltransferase and covers a broad range of GTP concentrations. Highly selective, high-affinity antibody enables nanomolar GDP detection in the presence of excess GTP. This assay accommodates GTP concentrations ranging from 1 μM to 1,000 μM with excellent data quality (Z’ ≥ 0.7) at low substrate conversion (typically 10-30%).