1GQ6:
reference: Oligomeric structure of proclavaminic acid amidino hydrolase: evolution of a hydrolytic enzyme in clavulanic acid biosynthesis., Elkins JM, Clifton IJ, Hernandez H, Doan LX, Robinson CV, Schofield CJ, Hewitson KS, Biochem J 2002 Sep 1;366(Pt 2):423-34. PMID: 12020346

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