Biochemistry
6th Edition
ISBN: 9781305577206
Author: Reginald H. Garrett, Charles M. Grisham
Publisher: Cengage Learning
expand_more
expand_more
format_list_bulleted
Question
Chapter 19, Problem 9P
Interpretation Introduction
Interpretation:
A suitable chemical mechanism for pyruvate decarboxylase reaction in yeast should be suggested.
Concept Introduction:
Transformation of pyruvate to acetyl-CoA is called pyruvate decarboxylation which is contributed by pyruvate dehydrogenase complex. Acetyl- CoA is used for
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
Compare and contrast Pyruvate Dehydrogenase with a-ketoglutarate dehydrogenaseOutline the mechanisms of both enzymes. Discuss the functions of the coenzymes. List the similarities and the differences between the 2 enzymes. Both are very large membrane bound complexes. What are the advantages of this strategy?How detailed is the enzyme structure known below(It's Pyruvate Dehydrogenase )? What insight(s) does this structural detail give you about the enzyme mechanism.
. Pyruvate can be processed under anaerobic conditions to ethanol (in yeast) or to lactate (in
mammals), as shown.
Explain the primary purpose of these reactions.
Describe the major biochemical features of each reaction
Based on the action of thiamine pyrophosphate in catalysis of the pyruvate dehydrogenase reaction, suggest a suitable mechanism for the fourth step in the pyruvate decarboxylase reaction in yeast:
Chapter 19 Solutions
Biochemistry
Ch. 19 - Radiolabeling with 14C-Glutamate Describe the...Ch. 19 - Prob. 2PCh. 19 - Assessing the Effect of Active-Site...Ch. 19 - Understanding the Mechanism of the -Ketoglutarate...Ch. 19 - Understanding the Action of Fluoroacetate on the...Ch. 19 - Prob. 6PCh. 19 - Prob. 7PCh. 19 - Prob. 8PCh. 19 - Prob. 9PCh. 19 - Prob. 10P
Ch. 19 - Prob. 11PCh. 19 - Prob. 12PCh. 19 - Prob. 13PCh. 19 - Prob. 14PCh. 19 - Prob. 15PCh. 19 - Prob. 16PCh. 19 - Understanding the Oxidation of Glucose and Its...Ch. 19 - Prob. 18PCh. 19 - Prob. 19PCh. 19 - Prob. 20PCh. 19 - Complete oxidation of a 16-carbon fatty acid can...Ch. 19 - Study Figure 19.18 and decide which of the...Ch. 19 - Prob. 23P
Knowledge Booster
Similar questions
- Ethanol as a Source of Metabolic Energy (Integrates with Chapters 19 and 20.) Acetate produced in ethanol metabolism can be transformed into acetyl-COA by the acetyl thiokinase reaction: Acetate+ATP+CoASHacetyleCoA+AMP+PPiAcetyle-CoA then can enter the citric acid cycle and undergo oxidation to 2 CO2by this route, assuming oxidative phosphorylation is part of the process? (Assume all reactions prior to acetyl-CoA entering the citric acid cycle occur outside the mitochondrion). Per carbon atom, which is a better metabolic fuel, ethanol or glucose? That is, how many ATP equivalents per carbon atom are generated by combustion of glucose versus ethanol to CO2?arrow_forwardDistinguishing the Mechanisms of Class I and Class I Aldolases Fructose bisphosphate aldolase in animal muscle is a class 1 aldolase, which forms a Schiff base intermediate between substrate (for example. fructose-1, 6-bisphosphate or dihydroxyacetone phosphate) and a lysine at the active site (see Figure I8.12). The chemical evidence for this intermediate conies from studies with aldolase and the reducing agent sodium borohydride, NaBH4. Incubation of the enzyme with dihydroxyacetone phosphate and NaBH4 inactivates the enzyme. Interestingly, no inactivation is observed if NabH4 is added to the enzyme in the absence of substrate. Write a mechanism that explains these observations and provides evidence for the formation of a Schiff base intermediate in the aldolase reaction.arrow_forwardThe Effect of lodoacetic Acid on the Glyceraldehyde-3-P Dehydrogenase Reaction (Integrates with Chapters 4 and 14.) How might iodoacetic acid affect the glyceraldehydes-3-phosphate dehydrogenase reaction in glycolysis? Justify your answer.arrow_forward
- Understanding the Mechanism of the 3-ketosphinganine Synthase Reaction Write a reasonable mechanism for the 3-ketosphinganine synthase reaction, remembering that it is a pyridoxal phosphate-dependent reaction.arrow_forwardSketch out the schematic diagram for the enzymatic mechanism of pyruvate dehydrogenase complex Please provide the structure of the functional groups of the substrate and enzyme involved in the reaction at each step (rest of the structure can be indicated as R) Indicate clearly the flow of electrons in the E-1 and E-2 reaction Indicate in short form the cofactor involvedarrow_forwardThe glyceraldehyde-3-phosphate-deshydrogenase glyceraldehyde-3-phosphate in 1,3-bisphosphoglycerate. catalyses the catalyses -CH₂ -CHOH—CHO + Pi + NAD* the oxidation of CH₂ CHOH-COQ + H* + NADH When the enzyme is incubated with iodoacetate, it is observed that glyceraldehyde-3- phosphate still binds to the modified enzyme, but it is not oxidized. What conclusion can be drawn from this experiment? Data: iodoacetate ICH₂COO is an alkylating reagent that react with free sulfhydryl groups (-SH) to form (-S-CH₂COO).arrow_forward
- Catalytic mechanism of the Pyruvate Dehydrogenase Complex Match the following coenzymes with the type of reaction or catalytic steps they are associated with during the catalysis of Pyruvate transformation into Acetyl-CoA by the Pyruvate Dehydrogenase Complex: NAD+ V [Choose] formation of a low energy thioester bond decarboxylation TPP oxidation/reduction formation of a high energy thioester bond Coenzyme A [ Choose ] Lipoyl Lysine [ Choose ] FAD [ Choose ]arrow_forwardCompare and contrast Pyruvate Dehydrogenase with a-ketoglutarate dehydrogenaseOutline the mechanisms of both enzymes. Discuss the functions of the coenzymes. List the similarities and the differences between the 2 enzymes. Both are very large membrane bound complexes. What are the advantages of this strategy?Do a bit or research on the structure one of these enzymes. (include one recent reference) – How detailed is the enzyme structure known? What insight(s) does this structural detail give you about the enzyme mechanism.arrow_forwardThe Payoff Phase of Glycolysis in Skeletal Muscle In the skeletal muscle, in anaerobic conditions, glyceraldehyde 3- phosphate is converted into pyruvate during the payoff phase of glycolysis; and this pyruvate is reduced into lactate during lactic fermentation. 1-Write the 11 balanced biochemical equations corresponding to all| the reaction steps leading to the conversion of glyceraldehyde-3- phosphate into lactate through glycolysis followed by lactic fermentation. 2-Write the net equation of the whole transformation process (i.e. with glyceraldehyde-3-phosphate as the starting substrate; and lactate as the end product).arrow_forward
- Puting a metabolic pathway map together which includes glycolysis, gluconeogenesis, glycogen synthesis & glycogenolysis, and the two types of fermentation, and pyruvate oxidation (to acetyl-CoA). The map should have/illustrate/show all of the indicated 6 pathways stated previously on the same page, to emphasize how these processes are related to each other. map should include: a) Clear labels for all the pathways b) All the pathways shown on the same page and correctly integrated with each other, i.e., it should be clear which reactions are shared by different pathways c) The names of all metabolites (common abbreviations may be used) d) The names of all enzymes e) All relevant cofactors/co-substrates discussed in class, clearly showing, where ATP is used and produced f) Double or single arrows representing reversible or irreversible reactions, respectively g) All "high-energy" intermediates clearly labeled with an asterisk (*) h) Labels for cellular locations of…arrow_forwardH. OH co co2 но H co, 1-isopropylmalate 2-isopropylmalate Biosynthesis of leucine involves conversion of 1-isopropyimalate to 2-isopropylmalate (see above). This proceeds in four steps under basic enzymic catalysis via an isolable compound produced in step 2. Write a detailed mechanism for this conversion. Then, draw the intermediate compound) produced in step 2. • You do not have to consider stereochemistry. • Draw uninvolved carboxyl groups in the anionic state, and enolates as carbanions. When needed, abbreviate CoenzymeA-S- as CH3S- In your drawing. aalearrow_forwardThe reaction catalyzed by malate dehydrogenase has a ΔG°′ value of +29.7 kJ⋅mol−1. Given what this says about the occurrence of the reaction catalyzed by malate dehydrogenase in cells explain how the reaction catalyzed by citrate synthase (−31.5 kJ⋅mol−1) influences that activity of malate dehydrogenase. In addition, explain how the activity of citrate synthase functions as a regulatory point for the citric acid cyclearrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- BiochemistryBiochemistryISBN:9781305577206Author:Reginald H. Garrett, Charles M. GrishamPublisher:Cengage Learning
Biochemistry
Biochemistry
ISBN:9781305577206
Author:Reginald H. Garrett, Charles M. Grisham
Publisher:Cengage Learning