Patent ID: 8603767

Claim:
A method of determining the effect of a test compound on a non-luminogenic enzyme activity in an assay sample not containing living cells, comprising: (a) contacting a test compound and a non-luminogenic enzyme so as to produce a first mixture; (b) contacting the first mixture with a luminogenic molecule so as to produce a first reaction mixture, wherein the luminogenic molecule is both a substrate of the non-luminogenic enzyme and a pro-substrate of a luciferase enzyme; (c) contacting the first reaction mixture with a reagent composition comprising luciferase and a tolerance enhancement agent so as to produce a second reaction mixture, wherein the tolerance enhancement agent is present in an amount sufficient to substantially protect the activity of the luciferase from interference from the test compound and thereby reduce the likelihood of a false positive resulting from the interfering effect of the test compound relative to the absence of the tolerance enhancement agent; (d) detecting luminescence in the second reaction mixture; and (e) determining the effect of the test compound, if any, on the non-luminescent enzyme activity by comparing the detected luminescence of step (d) to 1) the luminescence of a control reaction mixture similar to the first reaction mixture but not containing the test compound, or 2) the luminescence of another first reaction mixture containing the test compound at a different concentration.