Active, human Three Prime Repair Exonculease 1 enzyme, His-tagged protein (AA 1-286) expressed and purified from baculovirus-infected insect cells. The enzyme has been thoroughly validated with Transcreener dAMP Exonculease Assay Kit. For specific activity, please refer to the Certificate of Analysis for each individual enzyme lot and full sequence. Purity is >90% in a 50 mM Tris, 500 mM NaCl, and 20% glycerol buffer composition (pH 8.0). Currently used with the Transcreener assay at a concentration between 0.06 - 0.52 nM in a 10 μL reaction.