19670
We have recently shown that thermolysine , a protease enzyme obtained from Bacillus thermoproteolyticus rokko , can be used to trigger the gelation of FEFK ( F , phenylalanine ; E , glutamic acid ; K , lysine ) tetrapeptides through reverse hydrolysis and formation of longer peptide sequences , mainly octapeptides , that self - assemble readily .
 Chemical: phenylalanine; Chemical: glutamic acid; Chemical: lysine
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: phenylalanine; Chemical: glutamic acid; Chemical: lysine