a) describe the overall reaction catalyzed by the pyruvate dehydrogenase complex (PDH) and its regulation; b) outline the intermediates and enzymes of the TCA cycle; c) explain the relationship between the reactions of PDH and the TCA cycle and the respiratory chain.
Q: Identify the means by which the pyruvate dehydrogenase complex is regulated.
A: Pyruvate dehydrogenase is a convergence point in the regulation of the metabolic finetuning between…
Q: Briefly describe the dual role of lipoic acid in the pyruvate dehydrogenase complex
A: Lipoic acid is essentially used in aerobic processes. It is important biological compound for the…
Q: If NADH acts as a NEGATIVE regulator of citrate synthase, how could this conserve oxidizable carbons…
A: Cellular respiration is a catabolic pathway of the process of metabolism, where a series of chemical…
Q: Explain why the reaction catalyzed by the pyruvate dehydrogenase complex is a crucial juncture in…
A: The pyruvate dehydrogenase complex is a multifunctional enzyme that catalyzes the conversion of…
Q: Which of the following cofactors is NOT used by the pyruvate dehydrogenase complex? a. NAD+ b. FAD…
A: The pyruvate formed by the process of glycolysis is converted into acetyl-CoA. The reaction is…
Q: How many molecules of CO2, NADH, and FADH2 are releasedper pyruvate oxidized in the citric acid…
A: Cell is the smallest structural and, functional unit of life. It is simple machinery that houses all…
Q: Which of the following is a negative regulator of the pyruvate dehydrogenase complex (PDC)? 1.…
A: Pyruvate dehydrogenase complex (PDC) : It converts pyruvate to acetyl CoA via pyruvate…
Q: Which of the following catalyzes the reduction of oxygen by using the electrons released from…
A: Oxidative phosphorylation is the process of producing ATP by using the proton gradient generated by…
Q: Which one of the five steps of the pyruvate dehydrogenase complex reaction is most likely to be…
A: Pyruvate dehydrogenase complex is a group of non-covalently associated enzymes. It catalyzes…
Q: If oxidation of acetyl-CoA yields 10 ATPS per mole through the citric acid cycle, how many ATPS will…
A: Amino acids catabolism can either be done to produce urea by removal of α-amino groups or to form…
Q: There are three steps in the Kreb cycle (beginning at pyruvate) where a single carbon is removed. In…
A: Glycolysis is the main process of cellular respiration involving glucose (6C) conversion to two…
Q: Indicate whether each of the following aspects of the carnitine shuttle system associated with the…
A: Beta oxidation is an important process that is associated with the Krebs cycle. It catabolizes the…
Q: Identify at least five biological effects of disorders of the citric acid cycle
A: In our body their are lot of metabolism pathways are carried out apart from them citric acid cycle…
Q: What is the main purpose and importance of pyruvate oxidation in the cellular respiration?
A: Pyruvate is created by glycolysis within the cytoplasm, yet pyruvate oxidation happens in the…
Q: How does an increase in the NADH/NAD1 ratio affect the activity of pyruvate dehydrogenase?
A: Introduction: The citric acid cycle is a series of reactions that yield two carbon dioxide…
Q: Why does it make sense that under conditions of low ATP levels in the cell the pyruvate carboxylase…
A: Reaction catalyzed by Pyruvate carboxylase is given below; Pyruvate + CO2 + ATP + H2O →Pyruvate…
Q: What are the two most common inhibitors of stepsof the citric acid cycle and the reaction catalyzed…
A: The citric acid cycle that takes place in the mitochondrial matrix is the second step of aerobic…
Q: Identify the Krebs cycle enzyme which acts on a five-carbon substrate, produces a four-carbon…
A: Hello! Since you have posted multiple questions, we are answering the first question only. Kindly…
Q: Why does it make sense that under conditions of low ATP levels in the cell the pyruvate carboxylase…
A: Glucose is degraded to pyruvate through the process of glycolysis that occurs in the cytoplasm.…
Q: What is the significance of acetyl-CoA as a "strategic intermediate" in respiration?
A: The Krebs cycle is a metabolic mechanism that aids in the conversion of the pyruvate molecule to…
Q: Two carbon atoms are fed into the citric acid cycle as acetyl-CoA. In what form are two carbon atoms…
A: The citric acid cycle is the central metabolic pathway that involves the oxidation of acetyl CoA…
Q: Which of the following reactions/ pathways does NOT produce NADH? Payoff phase of glycolysis…
A: Anabolism is the process in which two small molecules will form a large molecule and in catabolism,…
Q: Given the following question, for each of the three reactions catalyzed by NADH dehydrogenase…
A: The mitochondrial respiratory chain or electron transport chain is a biological oxidation process in…
Q: Which of the following statements is/are TRUE for the Krebs' cycle? Reaction 1: condensation of…
A: Krebs cycle is the typical process for fully oxidizing proteins, lipids, and carbohydrates as they…
Q: If oxidation of acetyl-CoA yields 10 ATPs per mole through the citric acid cycle, how many ATPs will…
A: Introduction: The TCA cycle fundamentally includes the association of a two-carbon acetyl CoA with…
Q: Describe in detail the structure of the pyruvate dehydrogenase complex.
A: Introduction The formation of Acetyl-CoA from Pyruvate formed after Glycolysis is regulated by a…
Q: Which of the following carries electrons from the NADH dehydrogenase complex to the cytochrome c…
A: Ans. In a sequence of three large protein complexes, called NADH-Q oxidoreductase, Q-cytochrome c…
Q: a) What is the reason for the non-oxidative phase of the pentose phosphate pathway?
A: The pentose phosphate pathway is an alternative pathway that is employed to oxidize glucose by…
Q: If 30 molecules of acetyl CoA enter into the mitochondria in the presence of O2, how many molecules…
A: Cellular respiration is a series of metabolic reactions and processes carried out in the cells of…
Q: Malate synthase, an enzyme of the glyoxylate cycle, catalyzes the condensa- tion of glyoxylate with…
A: Cellular respiration is a catabolic pathway of the process of metabolism, where a series of chemical…
Q: When one acetyl CoA is processed through the citric acid cycle, how many times does each of the…
A: In aerobic condition, pyruvate in the presence of pyruvate dehydrogenase complex produces Acetyl…
Q: List the following substances in order of their increasing oxidizing power: (a) acetoacetate, (b)…
A: Oxidizing power - Oxidizing power is defined as the ability to gain electrons. Oxidation is define…
Q: Why is acetyl-CoA considered a “strategic intermediate” in respiration?
A: Respiration is the process of oxidation of nutrients to retrieve the energy stored in them.
Q: The two main goals of the citric acid cycle are: (a) citrate synthesis and gluconeogenesis…
A: The citric acid cycle was discovered by H. A. Kreb. The reactions of the citric acid cycle occur in…
Q: In which of the given steps of TCA cycle one C is lost from substrate in the form of CO2 as well as…
A: Cellular respiration is a biochemical process of oxidation of organic compounds in an orderly manner…
Q: From the complete oxidation of glucose (glucose → 6CO2), how many total NADH electron carriers are…
A:
Q: How come high levels of NADH indicate reduced coenzymes rather than oxidized coenzymes? Isn't…
A: The cellular respiration is the process that involves production of energy by the metabolism of…
Q: Explain why pyruvate does not enter the mitochondrion in the absence of oxygen?
A: Pyruvate is an important chemical compound in biochemistry.It is the output of the metabolism of…
Q: Which of the following enzymes possesses a catalytic mechanism extremely similar to that of the…
A: The pyruvate dehydrogenase complex resembles the alpha ketoglutarate dehydrogenase complex. The…
Q: In the first step of the TCA cycle the acetyl group of acetyl-CoA is transferred to oxaloacetate to…
A: Citric acid cycle, also known as tricarboxylic acid cycle or Krebs cycle occurs in the…
Q: describe how the pyruvate dehydrogenase complex is regulated?
A: Pyruvate dehydrogenase complex (PDC) is a three-enzyme complex that decarboxylates pyruvate into…
Q: Why are compounds such as glyceraldehyde- 3-phosphate, pyruvate, and acetyl-CoA so important in…
A: Glyceraldehyde 3-phosphate is an intermediate during glycolysis. Pyruvate is the end product of…
Q: If the pyruvate is labelled with 14C at its carbonyl carbon, how many rounds of the TCA cycle are…
A: Glycolysis is the primary biochemical pathway of cellular respiration that involves the conversion…
Q: Write an equation for the pyruvate dehydrogenase reaction.
A: The pyruvate dehydrogenase (PDC) complex is considered as the crucial complex, which is known to…
Q: Describe the role played by each enzyme, cofactor, andcoenzyme of the pyruvate dehydrogenase complex
A: Introduction: The conversion of pyruvate to acetyl-CoA is done by oxidative decarboxylation. This…
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- Describe the effects of (1) oligomycin and (2) uncouplers of oxidative phosphorylation, e.g., dinitrophenol (DNP), carbonyl cyanide-p- trifluoromethoxyphenylhydrazone (FCCP), on respiration and ATP synthesis when added to a suspension of mitochondria with excess malate, ADP, and inorganic phosphate (Pi).The large amount of energy used during aerobic exercise(e.g., running) requires large amounts of oxaloacetate.Explain why acetyl-CoA cannot be used to produceoxaloacetate in this circumstance. What is the sourceof oxaloacetate molecules during aerobic activity?2. (a) ( In contrast to the pyruvate dehydrogen- ase complex, the a-ketoglutarate dehydrogenase (aKGDH) complex is not up- or downregulated by phosphorylation or dephosphorylation. However, the complex exhibits cooperativity modulated by the presence of ADP, ATP, inorganic phosphate (Pi), and Ca2+, as illustrated by the diagram on the right for the bovine kidney enzyme complex. Note in the diagram how the addition of 10 μM Ca2+ shifts the affinity of the enzyme complex for aKG from 20 mM Pi/-Ca2+ to 20 mM Pi/+Ca2+. Calcium especially en- hances the cooperative influence of ADP and ATP. Using the expanded copy of the diagram at the end of the problem set, estimate the change in S0.5 (re- member that for allosteric enzymes S0.5 corresponds to KM of a nonallosteric enzyme) for the enzyme complex in the presence of 20 mM Pi/-Ca2+ and in the presence of 20 mM Pi/+Ca2+. Compare similarly the change in S0.5 for the enzyme in the presence of 20 mM Pi/-Ca2+ plus 1.6 mM ADP to the enzyme in the…
- After pyruvate is formed, it must either be converted to another molecule to enter the citric acid cycle and ultimately produce ATP by utilizing the electron-transport chain, or go through alternate pathways to produce NAD Identify the products formed in the pathway of pyruvate and indicate whether NADH+H or NAD are produced under aerobic and anaerobic respiration Drag the appropriate labels to their respective targets. ▸ View Available Hint(s) Reset Help Alcohol (ethanol) Aerobic Respiration Anaerobic Respiration Acetyl coenzyme A Normal cell Yeast Lactate NAD+ produced NADH+H* produced Submit End products NAD*/ NADH+H* Previous Answers Request Answer Group 1 Group 2 Exercising Muscle Lactate Group 2 Group 1 Group 2. Briefly describe the biological rationale for cach of the following allosteric phenomena: (a) activation of pyruvate carboxylase by acetyl-CoA; (b) acti- vation of pyruvate dehydrogenase kinase by NADH; (c) inhibition of isoci- trate dehydrogenase by NADH; (d) activation of isocitrate dehydrogenase by ADP; (e) inhibition of a-ketoglutarate dehydrogenase by succinyl-CoA; (f) activation of pyruvate dehydrogenase phosphatase by Ca*.Describe the common characteristic among the reactions catalyzed by pyruvate dehydrogenase (PDH), isocitrate dehydrogenase (ID), and alpha-ketoglutarate dehydrogenase (KD) based on reversibility.
- Explain the indirect effect that allosteric effectors have on pyruvate dehydrogenase activity through phosphorylation/dephosphorylation of components within the PDH-complex. 2. The proton-motive force is a measure of the potential energy generated across the mitochondrial inner membrane during electron transport. Explain the factors that constitute this potential energy, that will be converted to the chemical energy of ATP by the cell.Although phosphoesters are generally not energetic enough to donate the phosphate to make a high energy bond (e.g., a phosphoanhydride), the phosphate in PEP is used to convert ADP to ATP in the pyruvate kinase reaction. Carefully explain the ‘quirk’ of this reaction that makes it energetically feasible.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.
- Explain how pyruvate dehydrogenase regulated using covalent modification (E1) of pyuvate dehydrogenase complex can be (phosphorylation or dephosphorylation).a. Some of the acetyl-CoA used in the citric acid cycle is produced from pyruvate. List the reactants and products of this reaction. The reactants are pyruvate and The products are acetyl-CoA and In the process, a(n) is to b. Name an enzyme complex that catalyzes this reaction and list its negative effectors. is the enzyme complex that catalyzes this reaction. Its negative effectors are andDescribe how the reaction catalyzed by triose phosphate isomerase is required based on the substrate for glyceraldehyde 3-phosphate dehydrogenase. Contrast ATP consumed in the investment stage with substrate level phosphorylation reaction Describe reactions catalyzed by phosphoglycerate kinase and pyruvate kinase based on substrate level phosphorylation reactions.