2HU7:
reference: The Acylaminoacyl Peptidase from Aeropyrum pernix K1 Thought to Be an Exopeptidase Displays Endopeptidase Activity., Kiss AL, Hornung B, Radi K, Gengeliczki Z, Sztaray B, Juhasz T, Szeltner Z, Harmat V, Polgar L, J Mol Biol. 2007 Apr 27;368(2):509-20. Epub 2007 Feb 20. PMID: 17350041

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