our results and the results from the literature search suggest that the aminopeptidase cleaves amino-terminal methionine when it precedes residues of alanine , glycine , proline , serine , threonine , and valine but not when it precedes residues of arginine , asparagine , aspartic acid , glutamine glutamic acid , isoleucine , leucine , lysine , or methionine .
C0017797
glutamine
C0061472
glutamic acid