2864
The mutant Fc domain ( AglycoT - Fc1004 ) contained a total of 5 amino acid substitutions that conferred an activating to inhibitory ratio of 25 ( A / I ratio ; FcyRIIa - R131 : Fc gamma RIIb ) .
 amino acid
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 amino acid