IDO2 Reaction Solution is an optimized, proprietary formulation containing all the necessary reaction components for IDO2-catalyzed conversion of L-tryptophan (L-Trp) to kynurenine (Kyn) in in vitro enzyme activity assays. This product is intended to be used with the BPS IDO2 Inhibitor Screening Assay Kit (BPS Cat. #72022) and/or with purified, active IDO2, His-tag (BPS Cat. #71194) in combination with 1x IDO2 Assay Buffer (BPS Cat. #73004).