How can chemolithotrophs create a membrane pH gradient if they are not using traditional proton transporters such as complex I or III? a. They do not create pH gradients for use by the ATP synthase. b. Oxidation of extracellular substrates creates 'holes' in the membrane allowing protons to leak. c. Oxidation of extracellular substrates utilizes H2O as the oxygen source. This produces 2Ht. d. Instead of increasing proton concentration in the periplasmic space, these microorganisms neutralize protons in the cytoplasm.

How can chemolithotrophs create a membrane pH gradient if they are not using traditional proton transporters such as complex I or III? a. They do not create pH gradients for use by the ATP synthase. b. Oxidation of extracellular substrates creates 'holes' in the membrane allowing protons to leak. c. Oxidation of extracellular substrates utilizes H2O as the oxygen source. This produces 2Ht. d. Instead of increasing proton concentration in the periplasmic space, these microorganisms neutralize protons in the cytoplasm.

Biochemistry

6th Edition

ISBN:9781305577206

Author:Reginald H. Garrett, Charles M. Grisham

Publisher:Reginald H. Garrett, Charles M. Grisham

Chapter17: Metabolism: An Overview

Section: Chapter Questions

Problem 18P

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