Explain why a strain of yeast with a defect in the enzyme alcohol dehydrogenase can grow well under aerobic conditions, but not under anaerobic conditions. The yeast strain grows well when aerobic because acetaldehyde is quickly converted to lactate. The yeast strain uses CO2 to generate NAD+ when aerobic, but GAPDH needs NADH when anaerobic. The yeast strain grows equally well under aerobic and anaerobic, but polyphenol is lethal to this strain. The yeast strain cannot oxidize NADH to generate NAD+ for the GAPDH reaction when anaerobic. The yeast strain needs to generate ethanol in order to stimulate the PFK- 1 reaction when anaerobic.

Explain why a strain of yeast with a defect in the enzyme alcohol dehydrogenase can grow well under aerobic conditions, but not under anaerobic conditions. The yeast strain grows well when aerobic because acetaldehyde is quickly converted to lactate. The yeast strain uses CO2 to generate NAD+ when aerobic, but GAPDH needs NADH when anaerobic. The yeast strain grows equally well under aerobic and anaerobic, but polyphenol is lethal to this strain. The yeast strain cannot oxidize NADH to generate NAD+ for the GAPDH reaction when anaerobic. The yeast strain needs to generate ethanol in order to stimulate the PFK- 1 reaction when anaerobic.

Biochemistry

6th Edition

ISBN:9781305577206

Author:Reginald H. Garrett, Charles M. Grisham

Publisher:Reginald H. Garrett, Charles M. Grisham

Chapter26: Synthesis And Degradation Of Nucleotides

Section: Chapter Questions

Problem 14P: The Energy Cost of dTTP Synthesis (Integrates with Chapter 20.) Starting from HCO3, glutamine,...

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