Biochemistry
Biochemistry
9th Edition
ISBN: 9781319114671
Author: Lubert Stryer, Jeremy M. Berg, John L. Tymoczko, Gregory J. Gatto Jr.
Publisher: W. H. Freeman
Bartleby Related Questions Icon

Related questions

bartleby

Concept explainers

Question
100%

**Please answer as soon as possible!!!** Can you check if the answer below is correct/has correct information and can you correct it? 

Question 7. 

A: Key Changes to Glycolysis Due to the New Enzyme:

The new enzyme catalyzes the conversion of glyceraldehyde-3-phosphate to 3-phosphoglycerate by the addition of molecular hydrogen (H₂). This event is a novel shortcut in the glycolytic pathway, bypassing several steps. The specific changes include:

* Bypassing Glyceraldehyde-3-Phosphate Dehydrogenase (GAPDH):

- Glyceraldehyde-3-phosphate is directly converted to 3-phosphoglycerate without undergoing the traditional GAPDH-catalyzed reaction, which involves the generation of NADH.

*Avoiding Generation of NADH:

- The conventional glycolytic pathway involves the generation of NADH during the GAPDH-catalyzed step. By bypassing this step, the new pathway does not produce NADH directly in this reaction.

* Eliminating the Need for Phosphoglycerate Kinase (PGK) and Phosphoglycerate Mutase (PGM):

- Phosphoglycerate is directly formed without the need for PGK and PGM, which are enzymes involved in the conversion of 1,3-bisphosphoglycerate to 3-phosphoglycerate in the canonical glycolytic pathway.

B: Benefits of Shortening the Glycolytic Pathway: 

*Energy Efficiency:

- The new pathway may be more energy-efficient since it avoids the production of NADH. While NADH is an important molecule for oxidative phosphorylation and ATP generation, the direct conversion of glyceraldehyde-3-phosphate to 3-phosphoglycerate without NADH production might be advantageous under specific cellular conditions.

*Reduced Complexity and Resource Utilization:

- Shortening the glycolytic pathway eliminates the need for certain enzymes (e.g., GAPDH, PGK, PGM) and associated cofactors, simplifying the biochemical processes in the cell. This event could result in resource savings and reduce the metabolic burden on the cell.

*Rerouting Metabolites for Anabolic Processes:

- The shortcut may enable the rerouting of glycolytic intermediates for anabolic processes. By bypassing certain steps, the cell could channel metabolites toward biosynthetic pathways, supporting the synthesis of macromolecules required for growth and proliferation.

*Adaptation to Specific Environmental Conditions:

- The presence of this mutant yeast might confer a selective advantage in certain environmental conditions where a shorter glycolytic pathway is more beneficial. This adoption could enhance the yeast's fitness in specific niches.

*Regulation of Redox Balance:

- The absence of NADH production in the glycolytic pathway might impact the cellular redox balance. The cell may need compensatory mechanisms to maintain the necessary balance of oxidized and reduced cofactors in other metabolic pathways.  

This is the question: There is an experimental biochemist who has just discovered a mutant yeast whose glycolytic pathway was shorter because of the presence of a new enzyme that catalyzes the following reaction:

glyceraldehydes-3-phosphate + H2 ----------> 3-phosphoglycerate The research questions are
a) What are the key changes to glycolysis does this new pathway cause
b) Whether shortening the glycolytic pathway in this way benefits the cell



Expert Solution
Check Mark
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
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