4ME6:
reference: Crystal structures of d-alanine-d-alanine ligase from Xanthomonas oryzae pv. oryzae alone and in complex with nucleotides., Doan TT, Kim JK, Ngo HP, Tran HT, Cha SS, Min Chung K, Huynh KH, Ahn YJ, Kang LW, Arch Biochem Biophys. 2014 Jan 16;545C:92-99. doi: 10.1016/j.abb.2014.01.009. PMID: 24440607

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