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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- Energetics of the Hexokinase Reaction The standard-state free energy change. Gfor the hexokinase reaction, is — 1 6.7 kJ/mol. Use the values in Table I to calculate the value of Gfor this reaction in the erythrocyte at 37°C.Describe the common characteristic among the reactions catalyzed by pyruvate dehydrogenase (PDH), isocitrate dehydrogenase (ID), and alpha-ketoglutarate dehydrogenase (KD) based on reversibility.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).
- Given the following information on reduction potentials, calculate the standard free energy in kJ/mol based on your understanding of electron transfer through the pyruvate dehydrogenase complex. Round to nearest whole number. Lipoamide + 2H+ + 2e- → dihydrolipoamide ∆εο = -0.29 FAD + 2H+ + 2e- → FADH2 ∆εο = −0.01Explain the advantage to the cell of each of the following regulatory actions: a. The pyruvate dehydrogenase complex (PDC) is inhibited by ATP.b. Isocitrate dehydrogenase is stimulated by ADP.c. Pyruvate carboxylase is stimulated by acetyl-CoA.d. Citrate synthase is inhibited by NADH.e. PDC is inhibited by fatty acidsIn the complete b-oxidation of stearic acid (18:0), a) how many moles of acetyl CoA are produced? b) how many times would the fatty acid pass through the fatty acid spiral for complete oxidation? c) what is the total ATP produced in the citric acid cycle? d) how many moles of NADH are produced? e) how many moles of FADH2 are produced? f) how many moles of ATP are produced after all NADH are reoxidized in the respiratory chain? g) how many moles of ATP are produced after all FADH2 are reoxidized in the respiratory chain? h) how many moles of ATP are produced from the complete oxidation of stearic acid?
- In the complete b-oxidation of stearic acid (18:0), a)how many moles of acetyl CoA are produced? ________ b)how many times would the fatty acid pass through the fatty acid spiral for complete oxidation? ________ c)what is the total ATP produced in the citric acid cycle? ________ d)how many moles of NADH are produced? ________ e)how many moles of FADH2 are produced? ________ f)how many moles of ATP are produced after all NADH are reoxidized in the respiratory chain? ________ g)how many moles of ATP are produced after all FADH2 are…The pyruvate S lactate reaction in animals is reversible, but thepyruvate S ethanol fermentation in yeast is irreversible. ExplainBriefly describe the biological rationale for each of the following allosteric phenomena: (a) activation of pyruvate carboxylase by acetyl-CoA; (b) activation of pyruvate dehydrogenase kinase by NADH; (c) inhibition of isocitrate 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 Ca2+.
- The half-reactions involved in the lactate dehydrogenase (LDH) reaction and their standard reduction potentials are (see attached)). Calculate ΔG at pH 7.0 for the LDH-catalyzed reduction of pyruvate under the following conditions: (a) [lactate]/[pyruvate] = 1 and [NAD+]/[NADH] = 1. (b) [lactate]/[pyruvate] = 160 and [NAD+]/[NADH] = 160. (c) [lactate]/[pyruvate] = 1000 and [NAD+]/[NADH] = 1000. (d) Discuss the eff ect of the concentration ratios in Parts a–c on the direction of the reaction.Consider the oxidation of this compound:C3H5O3(OC4H7)3 + 18.5O2 → 15CO2 + 13H2O + 1, 941 kcal.a) Find the respiratory exchange ratio (RER), calorific equivalent, and energy release if theO2 is 2 liters/min. Are these values representative of fat? Why or why not? b) If the activity involves running for 45 minutes, how much kcal is expended?Consider the docosanoic acid, C21H43CO2H a. Label the a and B carbons b. Draw the acyl CoA derived from this fatty acid c. How many acetyl CoA molecules are formed by complete B-oxidation? d. How many cycles of B-oxidation are needed for complete oxidation? e. How many molecules of ATP are formed from the complete catabolism of this fatty acid?