Many metabolites are maintained at steady state concentrations that are far from equilibrium. A comparison of K'eg and Q, the mass-action ratio, can determine whether a metabolic reaction is far from equilibrium Fructose 6- phosphate ATP Fructose 1,6- bisphosphate ADP
Calculate Kaa for this reaction at T- 25.0 oC. AGO 14.2 kJ/mol
Number
K' eq =
Calculate the mass-action ratio, Q, from the approximate physiological concentrations for rat heart tissue shown at the right.
Number
Q =
Metabolite Concentration
(μ M)
Fructose 6- 87.0
phosphate
Fructose 1,6- 22.0
bisphosphate
ATP 12,100
ADP 1,310
Select the true statements about the PFK-1 reaction.
1. The PFK-1 reaction in heart tissue does not reach equilibrium.
2. In heart tissue, the PFK-1 products are more abundant than reactants.
3. In heart tissue, the PFK-1 reaction will be driven toward product formation.
4. Under standard conditions, the PFK-1 reaction reaches equilibrium when the concentrations of all products and reactants are equal.