The phosphoryl group transfer potentials of phosphorylated compounds with high hydrolysis values are substantial.

The phosphorylation and oxidative decarboxylation of oxaloacetate by inorganic phosphate (Pi) to make phosphoenolpyruvate and carbon dioxide is endergonic under intracellular conditions. It is characterized by this equation:   Oxaloacetate + Pi ←→ Phosphoenolpyruvate + H2O + CO2 ΔG’ = +24.6 kJ/mol   The synthesis of GTP from GDP and inorganic phosphate (Pi) in solution is endergonic under intracellular conditions, and it is characterized by this equation:   GDP + Pi ←→ GTP + H2O ΔG’ = +30.5 kJ/mol   Write a new net thermodynamically coupled reaction equation that describes the synthesis of phosphoenolpyruvate from oxaloacetate using the hydrolysis of GTP to power the reaction and calculate the new net ΔG’ of this reaction. Show all of your work.

Phosphorylated molecules with high _____________ values of hydrolysis have large phosphoryl group transfer potentials.

Free energy changes under intracellular conditions differ markedly from those determined under standard conditions. AG" =-30.5 kJ/mol for ATP hydrolysis to ADP and P,. Calculate AG for ATP hydrolysis in a cell at 37 °C that contains [ATP] =3 mM, [ADP] =1mM, and [P] =1 mM.