3NIP:
reference: Crystal structures of Pseudomonas aeruginosa guanidinobutyrase and guanidinopropionase, members of the ureohydrolase superfamily., Lee SJ, Kim DJ, Kim HS, Lee BI, Yoon HJ, Yoon JY, Kim KH, Jang JY, Im HN, An DR, Song JS, Kim HJ, Suh SW, J Struct Biol. 2011 May 12. PMID: 21600989

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