In this task, you are given a sentence. You are expected to recognize the name of gene or protein. Although there might be several correct answers, you need to write one of them.
Q: 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 ) .
A:
PAP mutants