8872
In addition , Raman microspectroscopy demonstrated that different cations affected structures of aromatic amino acid residues differently , which indicates that cation - pi interactions play an important role in determination of the final structure of protein molecules .
 Chemical: aromatic amino acid
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: aromatic amino acid