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Ethanol as a Source of Metabolic Energy (Integrates with Chapters 19 and 20.) Acetate produced in ethanol
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Check out a sample textbook solution- Complete oxidation of a 16-carbon fatty acid can yield 129 molecules of ATP Study Figure 19.2 and determine how many ATP molecules would be generated if a 16-carbon fatly acid were metabolized solely by the TCA cycle, in the form of S acetyl-CoA molecules.arrow_forwardUsing the ActiveModel for enoyl-CoA dehydratase, give an example of a case in which conserved residues in slightly different positions can change the catalytic rate of reaction.arrow_forwardExtending the Mechanism of Methylmalonyl-CoA Mutase to Similar Reactions Based on the mechanism for the methylmalonyl-CoA mutase (see problem 14), write reasonable mechanisms for the following reactions shown.arrow_forward
- A number of genetic deficiencies in acyl CoA dehydrogenases have been described. This deficiency presents early in life after a period of fasting. Symptoms include vomiting, lethargy, and sometimes coma. Not only are blood levels of glucose low ( hypoglycemia), but starvation-induced ketosis is absent. Provide a biochemical explanation for these last two observations.arrow_forwardThe citric acid cycle is shown. The methyl carbon in acetyl CoA is labeled with C14C14 (shown in red). Identify which of the carbons in each intermediate will be labeled in the first round of the cycle by selecting the indicated carbon(s). Each question has multiple options, please choose more than one. Which carbon(s) in α‑ketoglutarate will contain C14? 1 2 3 4 5 Which carbon(s) in succinyl‑CoA will contain C14? 1 2 3 4 Which carbon(s) in succinate will contain C14? 1 2 3 4 Which carbon(s) in fumarate will contain C14? 1 2 3 4 Which carbon(s) in malate will contain C14? 1 2 3 4 Which carbon(s) in oxaloacetate will contain C14? 1 2 3 4arrow_forwardThe total degradation of a fatty acid with an odd number of carbons yields acetyl-CoA and another compound, X. Show the structure of X, and describe the pathway by which it is converted into a citric acid cycle intermediate, including where any cofactors participate.arrow_forward
- 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.arrow_forwardClassify each reaction or process as one that decreases or replenishes the pool of oxaloacetate available for the activity of the citric acid cycle. Assume the reactions proceed in the forward direction. Decreases the oxaloacetate pool Replenishes the oxaloacetate pool Answer Bank reaction catalyzed by PEP carboxykinase reactions of gluconeogenesis reaction catalyzed by malic enzyme reaction catalyzed by PEP carboxylase reaction catalyzed by pyruvate carboxylasearrow_forwardThioester play an important role in glycolysis and the TCA cycle. Which reactions in glycolysis and tca cycle involve thioesters.arrow_forward
- Page > of 6 ZOOM + TCA cycle, oxidative phosphorylation, metabolic regulation TCA cycle (Ch. 16) 1. The citric acid cycle has eight enzymes: citrate synthase, aconitase, isocitrate dehydrogenase, a-ketoglutarate dehydrogenase, succinyl-CoA synthetase, succinate dehydrogenase, fumarase, and malate dehydrogenase. (a) Write a balanced equation for the reaction catalyzed by each enzyme. (b) Name the cofactor(s) required by each enzyme reaction. (c) For each enzyme determine which of the following describes the type of reaction(s) catalyzed: condensation (carbon–carbon bond formation); dehydration (loss of water); hydration (addition of water); decarboxylation (loss of CO2); oxidation-reduction; substrate-level phosphorylation; isomerization. (d) Write a balanced net equation for the catabolism of acetyl-CoA to CO2.arrow_forward1 2 points Order the following TCA cycle metabolites in the order they are produced in one turn of the citric acid cycle. Not all answers will be used. 2 1 4 3 TI Isocitrate Citrate Lactate Pyruvate Oxaloacetate Isocitrate Succinyl-CoA Aconitate 3-Phosphoglycerate -DOarrow_forwardMetabolizing a fatty acid via the B-oxidation pathway will generate acetyl CoA, NADH and FADH₂. Based on your biochemical knowledge, the major metabolic intermediate will enter cellular respiration in [Select] and the reduced coenzymes will enter cellular respiration in [Select] Could a mature red blood cell perform the ß-oxidation pathway? Yes, in their cytoplasm.arrow_forward
- BiochemistryBiochemistryISBN:9781305577206Author:Reginald H. Garrett, Charles M. GrishamPublisher:Cengage Learning