1PEU:
reference: Structure of the large subunit of class Ib ribonucleotide reductase from Salmonella typhimurium and its complexes with allosteric effectors., Uppsten M, Farnegardh M, Jordan A, Eliasson R, Eklund H, Uhlin U, J Mol Biol 2003 Jun 27;330(1):87-97. PMID: 12818204

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