Table 2. Models used in molecular dynamic simulations.

Model Name	Protein	Substrate (dTTP)
Model 1	open state dimer	(no substrate)
Model 2	closed state dimer	(no substrate)
Model 3	closed state monomer	docking result
Model 4	open state monomer	same as in Model 3
Model 5	open state dimer	same as in Model 3
Model 6	open state dimer	same as in Model 3
Model 7	closed state dimer	same as in Model 3
Model 8	closed state dimer	same as in Model 3

The “docking result” in Model 3 indicates that dTTP conformation with the lowest docking energy and largest clustering number are extracted for further calculation. dTTP conformation in other models are set by superimposition.