Use the molecular model (below) to obtain the measurements needed. The thin red lines link the atoms of interest.

1. Measure the distance between the 4-amino nitrogen atom and

   the hydroxy group of threonine (200).

2. Measure the distance between the 4-amino nitrogen atom and

   the adjacent water (red sphere) molecule.

3. Measure the distance between the closest sulfone oxygen

   atom (i.e. 7,7-dioxo) and the carboxamide nitrogen of glutamine (92).

Atom colours:
Carbon - grey (ligand = green); Oxygen - red; Nitrogen - blue; Sulfur - yellow; Hydrogen - white