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The reported bioisosteres share the following essential structural features for mimicking alpha - amino acids : an aromatic ring system joined to a lactam ring system with an acidic feature next to the lactam carbonyl , where this acidic feature together with the lactam carbonyl can mimic the alpha - carboxylate , and the lactam nitrogen together with the aromatic ring system can mimic the alpha - ammonium .
 Chemical: alpha - amino acids; Chemical: lactam carbonyl; Chemical: lactam carbonyl; Chemical: alpha - ammonium
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: alpha - amino acids; Chemical: lactam carbonyl; Chemical: lactam carbonyl; Chemical: alpha - ammonium