Figure 6.

Thermodynamics of ESV binding to MPro^WTand its catalytic dyad mutants.A, chemical structure of ensitrelivir (ESV). B, superposition of the crystal structures of MPro^WT-NMV (light pink cartoon, yellow carbon atoms) and MPro^WT-ESV (blue cartoon, cyan carbon atoms) complexes. H41 rotates ∼135° around the Cα-Cβ bond away from C145 to accommodate the chlorine atom present in P1′ group of ESV. C–E, binding isotherms of ESV to MPro^WT and catalytic dyad mutants. Titrations were performed in buffer C at 28 °C with 30 μM protein in the cell and inhibitor in the syringe. F, comparison of the K_d and enthalpy/entropy compensation upon binding of NMV and ESV to MPro^WT and catalytic dyad mutants (Table 1).