The antibiotic valinomycin is an ionophore that forms a specific complex with potassium ion. Because the complex is lipophilic and can diffuse into the membrane, valinomycin brings about the transport of K+ through the inner membrane. Valinomycin acts by decreasing the ∆ψ (membrane potential) component of the pmf, without a direct effect on the pH gradient. Another antibiotic, nigericin, acts as a K+ >H+ antiporter; itcarries H+ in one direction, coupled with the reverse transport of K+. Thus,nigericin dissipates the pH component of the pmf, with little effect on ∆c.Which antibiotic, nigericin or valinomycin, do you predict would have thegreater effect on oxidative phosphorylation when administered to respiring mitochondria? Assume the antibiotics are added to a suspension of mitochondria in equimolar amounts. Briefly explain your reasoning.

Biochemistry
9th Edition
ISBN:9781319114671
Author:Lubert Stryer, Jeremy M. Berg, John L. Tymoczko, Gregory J. Gatto Jr.
Publisher:Lubert Stryer, Jeremy M. Berg, John L. Tymoczko, Gregory J. Gatto Jr.
Chapter1: Biochemistry: An Evolving Science
Section: Chapter Questions
Problem 1P
icon
Related questions
Question

The antibiotic valinomycin is an ionophore that forms a specific complex with potassium ion. Because the complex is lipophilic and can diffuse into the membrane, valinomycin brings about the transport of K+ through the inner membrane. Valinomycin acts by decreasing the ∆ψ (membrane potential) component of the pmf, without a direct effect on the pH gradient. Another antibiotic, nigericin, acts as a K+ >H+ antiporter; it
carries H+ in one direction, coupled with the reverse transport of K+. Thus,
nigericin dissipates the pH component of the pmf, with little effect on ∆c.
Which antibiotic, nigericin or valinomycin, do you predict would have the
greater effect on oxidative phosphorylation when administered to respiring mitochondria? Assume the antibiotics are added to a suspension of mitochondria in equimolar amounts. Briefly explain your reasoning.

Expert Solution
trending now

Trending now

This is a popular solution!

steps

Step by step

Solved in 2 steps

Blurred answer
Knowledge Booster
Cell signaling
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
Biochemistry
Biochemistry
Biochemistry
ISBN:
9781319114671
Author:
Lubert Stryer, Jeremy M. Berg, John L. Tymoczko, Gregory J. Gatto Jr.
Publisher:
W. H. Freeman
Lehninger Principles of Biochemistry
Lehninger Principles of Biochemistry
Biochemistry
ISBN:
9781464126116
Author:
David L. Nelson, Michael M. Cox
Publisher:
W. H. Freeman
Fundamentals of Biochemistry: Life at the Molecul…
Fundamentals of Biochemistry: Life at the Molecul…
Biochemistry
ISBN:
9781118918401
Author:
Donald Voet, Judith G. Voet, Charlotte W. Pratt
Publisher:
WILEY
Biochemistry
Biochemistry
Biochemistry
ISBN:
9781305961135
Author:
Mary K. Campbell, Shawn O. Farrell, Owen M. McDougal
Publisher:
Cengage Learning
Biochemistry
Biochemistry
Biochemistry
ISBN:
9781305577206
Author:
Reginald H. Garrett, Charles M. Grisham
Publisher:
Cengage Learning
Fundamentals of General, Organic, and Biological …
Fundamentals of General, Organic, and Biological …
Biochemistry
ISBN:
9780134015187
Author:
John E. McMurry, David S. Ballantine, Carl A. Hoeger, Virginia E. Peterson
Publisher:
PEARSON