2GBG:
reference: Crystal Structures of DPP-IV (CD26) from Rat Kidney Exhibit Flexible Accommodation of Peptidase-Selective Inhibitors., Longenecker KL, Stewart KD, Madar DJ, Jakob CG, Fry EH, Wilk S, Lin CW, Ballaron SJ, Stashko MA, Lubben TH, Yong H, Pireh D, Pei Z, Basha F, Wiedeman PE, von Geldern TW, Trevillyan JM, Stoll VS, Biochemistry. 2006 Jun 20;45(24):7474-7482. PMID: 16768443

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