Task: Named Entity Recognition
Input (English):  We recently described the isolation and characterization of nontoxic PAP mutants , NT123 - 2 , which has a point mutation ( E176V ) in the active site that abolishes enzymatic activity , and NT124 - 3 , which has a nonsense mutation that results in deletion of the C - terminal 25 aa ( W237Stop ) .
Output (English): PAP mutants