Patent ID: 9068972
Filing Date: 2015-06-30
Classification: C12N,C12Q,G01N

Abstract:
1. A method for detecting and quantitatively measuring the mutagenic potency of a test substance, the method comprising: a) providing a test substance, b) providing a functional quantitative reporter-antibiotic resistance fusion construct to act as a dual reporter, wherein the dual reporter comprises an antibiotic reversion reporter and a quantitative reporter fused together in the same open reading frame and under the control of the same promoter, wherein the dual reporter possesses a reversion site at the N-terminus of the quantitative reporter-antibiotic resistance operon, wherein the dual reporter is cloned into a multicopy plasmid, and wherein mutations at the reversion site allow read-through of the fusion protein producing both an antibiotic resistance protein and a quantitative reporter protein, and further wherein, in the presence of an antibiotic, the production of the antibiotic resistance protein confers a selective advantage that causes amplification of mutant plasmids, thereby raising the level of quantitative reporter protein wherein the level of quantitative reporter protein is proportional to the number of mutation events at the reversion site, c) transforming a host cell with the multicopy plasmid, d) contacting the host cell to the test substance to induce mutations at the reversion site, e) amplifying the plasmids that have mutations at the reversion site, f) measuring the level of quantitative reporter protein, wherein the level of quantitative reporter protein is quantitatively proportional to the number of mutation events at the reversion site and therefore to the mutagenic potency of the test substance.