This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Biochemistry
[{'content': 'Aminoacyl t-RNA is not require for ? \nSelect and explain. \nA. Proline, B. Lysine, C. Hydroxylysine, D. Methionine', 'role': 'user'}, {'content': "Answer: C \nExplanation: Ans. is 'c' i.e., Hydroxylysine The initial step in protein synthesis is the activation of amino acid in which each of the 20 amino-acids is covalently attached to their respective t-RNA, forming specific amino acyl t-RNA.The reaction is catalyzed by aminoacyl t-RNA synthase.Hydroxyproline and hydroxylysine are not represented into genetic code, i.e. they to not have t-RNA capable of accepting them and inseing them into polypeptide chain. Therefore, they have to be synthesized post-translationally from proline and lysine residues in the polypeptides.", 'role': 'assistant'}]