1CM2:
reference: The aspartyl replacement of the active site histidine in histidine-containing protein, HPr, of the Escherichia coli Phosphoenolpyruvate:Sugar phosphotransferase system can accept and donate a phosphoryl group. Spontaneous dephosphorylation of acyl-phosphate autocatalyzes an internal cyclization., Napper S, Delbaere LT, Waygood EB, J Biol Chem 1999 Jul 30;274(31):21776-82. PMID: 10419492

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