4349
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 ) .
 GENE: PAP mutants
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: GENE 
Text: {0} 
Answer:
 GENE: PAP mutants