E + S1 -> ES; k1*E*S1
ES -> E + S1; k2*ES
ES -> E + P1; k3*ES
S2 -> P2; (Vm*S2)/(Km+S2)

k1 = 3.5
k2 = 6.2
k3 = 1.5
Km = (6.2+1.5)/3.5
Vm = 15
E = 10
S1 = 15
S2 = 15