BIOCHEMISTRY (LOOSELEAF)
BIOCHEMISTRY (LOOSELEAF)
6th Edition
ISBN: 9780190612399
Author: MCKEE
Publisher: Oxford University Press
bartleby

Concept explainers

bartleby

Videos

Question
Book Icon
Chapter 4, Problem 26RQ
Summary Introduction

To review:

The concentration of phosphate at equilibrium is to be calculated.

Introduction:

Glucose-6-phosphatase is the enzyme thatcarries out the hydrolysis of glucose-6-phosphate. The end product of the hydrolysis is a phosphate group and a free glucose molecule. This hydrolysis reaction is an instrumental step in the production of glucose through gluconeogenesis.∆Go’ for the hydrolysis of glucose-6-phosphate is –13.8 kJ/mol (kilojoule per mole).

Expert Solution & Answer
Check Mark

Explanation of Solution

The hydrolysis reaction of glucose-6-phosphate is shown below:

Glucose6phosphateGlucose+pi

In case the pH (potential of hydrogen) is 7, the change in Gibbs free energy is denoted by ∆Go’. ∆Go’ for the hydrolysis of glucose-6-phosphate is –13.8 kJ/mol (kilojoule per mole) and the concentration of glucose-6-phosphate is4mM (millimolar).

Change in Gibb’s free energy (ΔG), standard Gibb’s free energy change (ΔG°'), and equilibrium constant Keq are related as

ΔG=ΔG°+RTlnKeq

At equilibrium, ΔG=0, thus, the above equation will be:

ΔG=ΔG°'+RTlnKeq0=ΔG°'+RTlnKeqΔG°'=RTlnKeqlnKeq=ΔG°'RT

Calculate the value of equilibrium constant by substituting the values of ΔG°'=13.8kJ/mol, R=0.008314 kJ K1mol1, and T=298K in the above expression:

lnKeq=(13.8 kJ/mol )0.008314 kJ K1mol1×298 KlnKeq=13.8 kJ/mol 2.477lnKeq=5.57Keq=262.43

The hydrolysis reaction of glucose-6-phosphate is as follows:

Glucose6phosphateGlucose+pi

The equilibrium constant is related to equilibrium concentrations of the reactants and products as

Keq=[Glucose] [Pi][Glucose6phosphate][Pi]=Keq×[Glucose6phosphate][Glucose]

Here, the concentration of glucose is ignored because glucose is exported out of the cell as soon as it is produced through the hydrolysis reaction. Thus, the above expression becomes:

[Pi]=Keq×[Glucose6phosphate]

Substitute Keq=262.43 and [Glucose6phosphate]=4mM in the above expression to get:

[Pi]=262.43×4mM=1049.72mM1.0×103mM

Conclusion

Therefore, it can be concluded that the final concentration of inorganic phosphate is 1.0×103mM.

Want to see more full solutions like this?

Subscribe now to access step-by-step solutions to millions of textbook problems written by subject matter experts!
Students have asked these similar questions
The breakdown of a complex carbohydrate into its monomeric unit can be described as an enzyme-catalyzed reaction that has a deltaG(∆G) of -90kcal/mol. Suppose you were to add triple the amount of enzyme into this reaction - what would be the ∆G of this reaction?
When a mixture of 3-phosphoglycerate and 2-phosphoglycerate is incubated at 25°C in the presence of the enzyme  phosphoglycerate mutase (which catalyzes the intervconversion of the two substances) until equilibrium is reached,  the final mixture contains 6 times as much 2-phosphoglycerate as 3-phosphoglycerate.  Which of the following statements is most nearly correct when applied to the reaction shown below: 3-phosphoglycerate ------> 2-phosphoglycerate (R=8.315 J/mole.K)   A. △G°' = +12.7 kJ/mole   B. △G°' = 0   C. △G°'  is incalculably large and positive   D. △G°' = -4.44 kJ/mole   E. △G°'  cannot be calculated from the information gven
What special properties of transition metals make them especially useful in enzyme catalysis?
Knowledge Booster
Background pattern image
Biochemistry
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, biochemistry and related others by exploring similar questions and additional content below.
Similar questions
SEE MORE QUESTIONS
Recommended textbooks for you
Text book image
Biochemistry
Biochemistry
ISBN:9781319114671
Author:Lubert Stryer, Jeremy M. Berg, John L. Tymoczko, Gregory J. Gatto Jr.
Publisher:W. H. Freeman
Text book image
Lehninger Principles of Biochemistry
Biochemistry
ISBN:9781464126116
Author:David L. Nelson, Michael M. Cox
Publisher:W. H. Freeman
Text book image
Fundamentals of Biochemistry: Life at the Molecul...
Biochemistry
ISBN:9781118918401
Author:Donald Voet, Judith G. Voet, Charlotte W. Pratt
Publisher:WILEY
Text book image
Biochemistry
Biochemistry
ISBN:9781305961135
Author:Mary K. Campbell, Shawn O. Farrell, Owen M. McDougal
Publisher:Cengage Learning
Text book image
Biochemistry
Biochemistry
ISBN:9781305577206
Author:Reginald H. Garrett, Charles M. Grisham
Publisher:Cengage Learning
Text book image
Fundamentals of General, Organic, and Biological ...
Biochemistry
ISBN:9780134015187
Author:John E. McMurry, David S. Ballantine, Carl A. Hoeger, Virginia E. Peterson
Publisher:PEARSON
Metabolic Pathways; Author: Wisc-Online;https://www.youtube.com/watch?v=m61bQYio9ys;License: Standard Youtube License