multisubstrate reactions

Question 1

random substrate binding

Answer 1

substrate 1 or substrate 2 can bind, there is not order of binding. (S1 or S2)

Question 2

ordered substrate binding

Answer 2

S1 binds before S2, because S1 sets up the binding site for S2.

Question 3

ping-pong mechanism

Answer 3

the 1st product of S1 must leave before S2 can bind. S1 modifys E in some way, such as adding a functional group.