Fig. 1
From: Comprehensive analysis of the Co-structures of dipeptidyl peptidase IV and its inhibitor
Inhibitor binding area of DPP-4. Representative image from the cocrystal structure of sitagliptin and DPP-4 (PDB ID: 1X70). The carbon skeleton of sitagliptin is represented by green stick. The carbon skeleton of 14 residues is labeled and represented by yellow stick. Val656 and Trp659 are positioned on the opposite side of view in this Figure; thus, they are not shown. O, N, and halogen atoms are labeled in red, blue and light blue sticks, respectively. The subsites, which are directly involved with binding to inhibitors (S1, S1′, S2, S2′ and S2 extensive), are labeled in orange