28068
Like Artemis , Metnase efficiently trimmed overhangs terminated in 3 ' - phosphoglycolates ( PGs ) , and in some cases the presence of 3 ' - PG stimulated cleavage and altered its specificity .
 Chemical: 3 ' - phosphoglycolates; Chemical: PGs; Chemical: 3 ' - PG
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 Chemical: 3 ' - phosphoglycolates; Chemical: PGs; Chemical: 3 ' - PG