2J9P:
reference: Crystal Structure of the Bacillus subtilis Penicillin-binding Protein 4a, and its Complex with a Peptidoglycan Mimetic Peptide., Sauvage E, Duez C, Herman R, Kerff F, Petrella S, Anderson JW, Adediran SA, Pratt RF, Frere JM, Charlier P, J Mol Biol. 2007 Aug 10;371(2):528-39. Epub 2007 Jun 2. PMID: 17582436

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