17143
Serine qua non : Substitution of the extended Ser13 in the core peptide of nosiheptide by analogous amino acids prevented enamide dealkylation of the terminal residue for nosiheptide maturation .
 Chemical: Serine; Chemical: Ser13; Chemical: nosiheptide; Chemical: amino acids; Chemical: enamide; Chemical: nosiheptide
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: Serine; Chemical: Ser13; Chemical: nosiheptide; Chemical: amino acids; Chemical: enamide; Chemical: nosiheptide