1QB4:
reference: Plausible phosphoenolpyruvate binding site revealed by 2.6 A structure of Mn2+-bound phosphoenolpyruvate carboxylase from Escherichia coli., Matsumura H, Terada M, Shirakata S, Inoue T, Yoshinaga T, Izui K, Kai Y, FEBS Lett 1999 Sep 17;458(2):93-6. PMID: 10481043

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