**5. Explanation of a Metabolic Pathway Involving "Blue Fish"**A metabolic pathway leading to the end product “Blue fish” is depicted below. The enzymes facilitating each step are shown in italics above the respective arrows. The committed step involves the transformation of One Fish to Two Fish by Seuss1.**a. Committed Step and Allosteric Control**- **Explanation of the Committed Step**: The committed step in a metabolic pathway is the point after which the substrate is irreversibly committed to proceeding through the pathway to produce the final product. It often represents the first irreversible reaction unique to the pathway. - **Role of Seuss1**: It makes sense for Seuss1 to catalyze this step because controlling an early, committed step allows the regulation of the entire pathway efficiently. This step is most likely allosterically controlled to allow for rapid response to changes in cellular conditions, ensuring metabolic balance.**b. Allosteric Regulation by Blue Fish**Blue Fish acts as an allosteric ligand to regulate the activity of Seuss1. The binding areas for the substrate of Seuss1 (One Fish) are highlighted by circles. An arrow can be drawn to indicate that Blue Fish might bind at sites distinct from the active site, as allosteric sites are typically separate from substrate binding sites. This binding can alter enzyme activity, supporting the explanation.**c. Enzymatic Activity in Presence of Blue Fish**- **Graph Analysis**: In the graph, the solid line labeled “Control” represents the normal activity of Seuss1, with the x-axis (S) depicting the concentration of Blue Fish. The dotted lines are hypothetical activities of Seuss1 under high concentrations of Blue Fish.- **Determining Impact**: One could interpret the presence of Blue Fish as altering enzyme activity, likely by reducing the maximum velocity (Vmax) or changing the affinity (Km) for the substrate.- **Conclusion on Regulation**: The graph potentially illustrates a decrease in Vmax, suggesting that Blue Fish reduces the enzyme’s maximal catalytic efficiency, likely signifying its role as an allosteric inhibitor rather than affecting Km significantly.These insights highlight the nuanced regulatory mechanisms in metabolic pathways, emphasizing the importance of enzyme regulation through allosteric interactions.

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Answered: Briefly explain what the "committed…

Briefly explain what the "committed step" of a pathway is. Also explain why it makes sense for Seuss1 to catalyze the committed step, and why this step is most likely to be allosterically controlled.

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

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