Fig. 2
From: Structure-based design of pan-coronavirus inhibitors targeting host cathepsin L and calpain-1
Crystal structures of human CTSL, CAPN1 protease core, and SARS-CoV-2 Mpro in complex with 14a and 14b, respectively. a A comparison of the binding modes of 14a and 14b in human CTSL substrate-binding pocket. The major difference between both compounds is marked with a dashed rounded circle. Both compounds are shown as ball-and-stick models with the carbon atoms in salmon (14a), bright orange (14b), oxygen atoms in bright red, nitrogen atoms in blue, and fluorine atom in cyan (the same as below, unless otherwise indicated). b, c Close-up view of inhibitor binding pocket for 14a (b) and 14b (c) in human CTSL. Residues involved the binding of inhibitors are shown as milky sticks. Hydrogen bonds are indicated as dashed lines. d A comparison of the binding modes of 14a and 14b in human CAPN1 protease core substrate-binding pocket. The major difference between both compounds is marked with a dashed rounded circle. e, f Close-up view of the binding pocket of 14a (e) and 14b (f) in human CAPN1 protease core. Residues involved in the binding of inhibitors are shown as light gray sticks. Hydrogen bonds are indicated as dashed lines. g A comparison of the binding modes of 14a and 14b in SARS-CoV-2 Mpro substrate-binding pocket. The major difference between both compounds is marked with a dashed rounded rectangle. h, i Close-up view of the binding pocket of 14a (h) and 14b (i) in SARS-CoV-2 Mpro. Residues involved in the binding of inhibitors are shown as pale-cyan sticks. Hydrogen bonds are indicated as dashed lines
