In the hydrolysis of ATP to ADP and Pi, the equilibrium concentration of ATP is too small to be measured accurately. A better way of determining K’eq, and hence ΔG◦’ of this reaction, is to break it up into two steps whose values of ΔG◦’ can be accurately determined. This has been done using the following pair of reactions (the first being catalyzed by glutamine synthetase): (1) ATP + glutamate + NH3 ⇌ ADP + Pi + glutamine + H+ ΔG1◦’= -16.3 kJ/mol (2) glutamate + NH3 ⇌ glutamine + H2O + H+ ΔG2◦’= 14.2 kJ/mol What is the ΔG◦’ of ATP hydrolysis according to these data and is the overall reaction spontaneous?What is the value of the equilibrium constant for the overall reaction at 25.0 °C.If the concentration of ATP at equilibrium is 20.0 mM and the concentration of ADP at equilibrium is 50 nM. What is the concentration the phosphate group (in mM) at equilibrium?

∆G'° for any reaction is a fixed parameter as it is defined by standard condition. For spontaneous…

What is the ΔG◦’ of ATP hydrolysis according to these data and is the overall reaction spontaneous? What is the value of the equilibrium constant for the overall reaction at 25.0 °C. If the concentration of ATP at equilibrium is 20.0 mM and the concentration of ADP at equilibrium is 50 nM. What is the concentration the phosphate group (in mM) at equilibrium?

What is the ΔG◦’ of ATP hydrolysis according to these data and is the overall reaction spontaneous? What is the value of the equilibrium constant for the overall reaction at 25.0 °C. If the concentration of ATP at equilibrium is 20.0 mM and the concentration of ADP at equilibrium is 50 nM. What is the concentration the phosphate group (in mM) at equilibrium?

Biochemistry

6th Edition

ISBN:9781305577206

Author:Reginald H. Garrett, Charles M. Grisham

Publisher:Reginald H. Garrett, Charles M. Grisham

Chapter25: Nitrogen Acquisition And Amino Acid Metabolism

Section: Chapter Questions

Problem 22P

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