For Michaelis-Menten phosphatase X with a Ks for substrate binding of 0.85 x 10-8 M, half maximal velocity is achieved with a substrate concentration of 0.35 μM.
a. What kind of kinetics does this enzyme follow: rapid equilibrium or just the general steady state? Justify your answer.
b. How many times larger is the catalytic rate constant than the reverse rate constant for substrate binding, k-1, by this phosphatase?
c. How many times smaller is the catalytic rate constant than the rate constant for substrate binding, k1?
d. How many times Km must the substrate concentration be in order to achieve a velocity that is 90% of Vmax?
e. If the [E]total is increased 5 times in a reaction while [S] is left constant, how much greater will the initial velocity be?