21572
The mutagenesis of conserved amino acid residues revealed that in addition to the five M beta L family conserved motifs , YycJ appears to have its specific motifs that can be used to distinguish YycJ from other closely related M beta L family members .
 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