10051
Substitution of Mag2 Asp56 , which caps the helix at the base of the DNA intercalation loop , with the corresponding serine residue in Mag1 endows Mag2 with epsilon A excision activity comparable to Mag1 .
 Chemical: serine
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: serine