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
Glycine is useful in all of the following synthetic processes, EXCEPT: 
Select and explain. 
A. Purine synthesis, B. Creatine synthesis, C. Heme synthesis, D. Synthesis of spermine
D: Synthesis of spermine
Answer: D: Synthesis of spermine 
Explanation: 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.