2GAR:
reference: A pH-dependent stabilization of an active site loop observed from low and high pH crystal structures of mutant monomeric glycinamide ribonucleotide transformylase at 1.8 to 1.9 A., Su Y, Yamashita MM, Greasley SE, Mullen CA, Shim JH, Jennings PA, Benkovic SJ, Wilson IA, J Mol Biol. 1998 Aug 21;281(3):485-99. PMID: 9698564

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