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': 'Glycine is useful in all of the following synthetic processes, EXCEPT: \nSelect and explain. \nA. Purine synthesis, B. Creatine synthesis, C. Heme synthesis, D. Synthesis of spermine', 'role': 'user'}, {'content': "Answer: D \nExplanation: Glycine is incorporated into creatine, and the nitrogen and -carbon of glycine are incorporated into the pyrrole rings and the methylene bridge carbons of heme, and the entire glycine molecule becomes atoms 4, 5, and 7 of purines. Following decarboxylation of S-adenosylmethionine by methionine decarboxylase, three carbons and the alpha-amino group of methionine contribute to the biosynthesis of the polyamines spermine and spermidine. Ref: Rodwell V.W. (2011). Chapter 30. Conversion of Amino Acids to Specialized Products. In D.A. Bender, K.M. Botham, P.A. Weil, P.J. Kennelly, R.K. Murray, V.W. Rodwell (Eds), Harper's Illustrated Biochemistry, 29e.", 'role': 'assistant'}]