5OLJ:
reference: Crystal structure of Porphyromonas gingivalis dipeptidyl peptidase 4 and structure-activity relationships based on inhibitor profiling., Rea D, Van Elzen R, De Winter H, Van Goethem S, Landuyt B, Luyten W, Schoofs L, Van Der Veken P, Augustyns K, De Meester I, Fulop V, Lambeir AM, Eur J Med Chem. 2017 Aug 10;139:482-491. doi: 10.1016/j.ejmech.2017.08.024. PMID: 28826083

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