Question

a. What is the Km and Vmax for PFK1 when treated with OmM (represents control for enzymatic activity) or with 5mM AMP Show work on the graph draw lines for Vmax and Km. Control: Vmax (AMP), 0.32 0.28 0.2 Km 0.24 0.20 (s)-FTY20 (20LM): 0.18 Vmax 0.12 0.08 0.04 Km 0.00 Fructose-6-phosphate (mM) b. Fructose-6-phosphate is the substrate of the reaction. Based on answer in "a", what type of regulation occurs with and what site on PFK1 is AMP likely binding to (active or regulatory site allosteric)? PFK-1 activity Aabs/min)

Answer 1

a. At 0 mM of cAMP
Vmax = 0.19 abs/min
Km = 10 mM

At 5 mM of cAMP
Vmax = 0.32 abs/min
Km = 1 mM

b. It is reducing the Km and increasing the Vmax.
cAMP is an allosteric activator.
It binds at an allosteric site on the enzyme.

(AMP), - - - - - - Fructose-6-phosphate (mm)

1M 1/[F6P]