1QM4:
reference: The crystal structure of tetrameric methionine adenosyltransferase from rat liver reveals the methionine-binding site., Gonzalez B, Pajares MA, Hermoso JA, Alvarez L, Garrido F, Sufrin JR, Sanz-Aparicio J, J Mol Biol 2000 Jul 7;300(2):363-75. PMID: 10873471

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