7731
We recently discovered that the residues Met626 and Thr627 preceding the pocket - binding domain of the C peptide adopt a unique M - T hook structure that is crucial for the design of HIV - 1 fusion inhibitors .
 Chemical: Met626; Chemical: Thr627
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: Met626; Chemical: Thr627