SAPLINGPLUS FOR PRINCIPLES OF BIOCHEMIS
SAPLINGPLUS FOR PRINCIPLES OF BIOCHEMIS
7th Edition
ISBN: 9781319424572
Author: nelson
Publisher: MAC HIGHER
bartleby

Concept explainers

bartleby

Videos

Question
Book Icon
Chapter 6, Problem 14P

(a)

Summary Introduction

To determine: The value of Vmax and Km of enzyme prostaglandin endoperoxide synthase.

Introduction:

Prostaglandin is class of lipid which is present at a site of injury and tissue damage in body. It is involved in healing process and induces inflammation, and initiation of pain.

(a)

Expert Solution
Check Mark

Explanation of Solution

Pictorial representation:

Table 1 shows the rate of formation of prostaglandin from arachidonic acid and Fig.1 shows the Lineweaver Burk plot, a double reciprocal plotting for 1/V0 Vs. 1/[S].

Table 1

SAPLINGPLUS FOR PRINCIPLES OF BIOCHEMIS, Chapter 6, Problem 14P , additional homework tip  1

SAPLINGPLUS FOR PRINCIPLES OF BIOCHEMIS, Chapter 6, Problem 14P , additional homework tip  2

Fig.1: Lineweaver Burk plot.

Lineweaver-Burk equation is the reciprocal of Michaelis-Menten equation, and given as:

Michaelis-Menten equation V°=Vmax[S]Km+[S]

Lineweaver-Burk equation 1V°=KmVmax[S]+1Vmax

So, by reciprocating the values given in first and second columns of the given table, we get 1/[S] and 1/V0 values in absence of the inhibitor, as mentioned in Table 1. By plotting these values we obtain the Lineweaver-Burk graph depicted in Fig.1. From the graph, calculating the V max in the absence of inhibitor:

y-axisintercept=-1VmaxVmax=10.0194=51.54mM51.5 mM/min

Calculating the Km in the absence of inhibitor:

x-axisintercept=-1KmKm=11.7=0.588mM0.59 mM

Conclusion

The Vmax of enzyme in the absence of inhibitor is 51.5mM/min, while Km of enzyme in the absence of inhibitor is 0.59mM.

(b)

Summary Introduction

To determine: The type of inhibition that ibuprofen exerts on prostaglandin endoperoxide synthase.

Introduction:

Enzyme inhibitors are defined as chemical molecules that bind at active site of enzymes and prevent the binding of substrate with enzyme. There are two types of inhibitors such as reversible and irreversible inhibitors.

(b)

Expert Solution
Check Mark

Explanation of Solution

Lineweaver-Burk equation is the reciprocal of Michaelis-Menten equation is given as:

Michaelis-Menten equation V°=Vmax[S]Km+[S]

Lineweaver-Burk equation 1V°=KmVmax[S]+1Vmax

So, by reciprocating the given values in column first and third, we get the rate of formation of prostaglandin from arachidonic acid in presence of inhibitor ibuprofen, as mentioned in Table 1. By plotting these values we obtain the Lineweaver-Burk graph for 1/[S] and 1/V0 in presence of inhibitor, as depicted in Fig.1.

Calculating the Vmax in presence of inhibitor:

Vmax in the presence of inhibitor:

y axis-intercept=1VmaxVmax=-1y axis-intercept=10.0194=51.54mM/min

Km of enzyme in the presence of inhibitor:

x axis-intercept=1KmKm=1x axis-intercept=11.2=0.83mM

The Vmax of enzyme both in the presence and absence of inhibitor is 51.54 mM/min, while Km of enzyme in the presence and absence of inhibitor is 0.83mM and 0.59mM.

Prostaglandin is involved in initiation of pain, and it is synthesized by prostaglandin endoperoxide synthase. Ibuprofen inhibits the activity of this enzyme by binding at the active site and preventing binding of substrate with enzyme. The double reciprocal graph in Fig.1 shows when competitive inhibitor ibuprofen is present, the Vmax remains unchanged while Km increases. Thus, -1/Km value is closer to the origin in the graph depicted in Fig.1. In competitive inhibition, Vmax remains unchanged while Km increases. Therefore, ibuprofen is a competitive inhibitor of prostaglandin.

Conclusion

The inhibition of prostaglandin by ibuprofen is example of competitive inhibition.

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
Biochemistry What is the process of "transamination" in either the muscles or the liver, that involves keto acid or glutamic acid? Please explain how the steps work. Thank you!
Biochemistry Please help. Thank you What is the importance of glutamic acid in the metabolism of nitrogen from amino acids? (we know therole; it’s used to remove the nitrogen from amino acids so that the remaining carbon skeleton can bebroken down by the “usual” pathways, but what is the important, unique role that only glutamicacid/glutamate can do?)
Biochemistry Please help. Thank you When carbamyl phosphate is joined to L-ornathine, where does the energy for the reaction come from?
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
Enzyme Kinetics; Author: MIT OpenCourseWare;https://www.youtube.com/watch?v=FXWZr3mscUo;License: Standard Youtube License