This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Translation, Subject name: Biochemistry
[{'content': 'Aminoacyl tRNA synthetase is required for all except: \nSelect and explain. \nA. Lysine, B. Cysteine, C. Methionine, D. Hydroxyproline', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Some proteins contain additional amino acids that arise due to post-translational modification of existing amino acyl residues. Examples: Vitamin C mediated hydroxylation of proline and peptidyl lysine to 4-hydroxyproline and 5-hydroxylysine Vitamin K mediated g-carboxylation of glutamate Methylation Formylation Acetylation Prenylation (addition of fatty acid residues) Glypiation (addition of Glycosyl PI anchor) Phosphorylation Therefore Aminoacyl tRNA synthetase is not required by these.', 'role': 'assistant'}]