1JKJ:
reference: Two glutamate residues, Glu 208 alpha and Glu 197 beta, are crucial for phosphorylation and dephosphorylation of the active-site histidine residue in succinyl-CoA synthetase., Fraser ME, Joyce MA, Ryan DG, Wolodko WT, Biochemistry 2002 Jan 15;41(2):537-46. PMID: 11781092

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