2. The overall reaction for the activation of a fatty acid to fatty acyl-CoA, with concomitant hydrolysis of ATP to AMP, has a free energy change of about zero. The reaction is favorable because of subsequent hydrolysis of pyrophosphate to orthophosphate (the reaction has a AG°' value of -19.2 kJ · mol-1). a. Write the equation for the coupled reaction and calculate AG°¹ (assume a temperature of 25°C). b. Calculate the equilibrium constant for the reaction. .

11. Quantitative Relationships between Rate Constants to Calculate Km, Kinetic Efficiency (kcat/Km) and Vmax - II Triose phosphate isomerase catalyzes the conversion of glyceraldehyde-3-phosphate to dihydroxyacetone phosphate. Glyceraldehyde-3-P dihydroxyacetone-P The Km of this enzyme for its substrate glyceraldehyde-3-phosphate is 1.8 x 10-5 M When [glyceraldehydes-3-phosphate] = 30 μM, the rate of the reaction, v, was 82.5 μmol mL-1 s-1. a. What is Vmax for this enzyme? b. Assuming 3 nm/mL of enzyme was used in this experiment (E total = 3nm/mL) for this enzyme? c. What is the catalytic efficiency (kcat/km) for triose phosphate isomerase? d. Does this enzyme reach catalytic perfection?

The conversion of dihyroxyacetone phosphate to glyceraldehyde 3-phosphate, catalyzed by triose phosphate isomerase, has an equilibrium constant of Keq’ = 0.0475. Calculate the standard free-energy change for this reaction at 25ºC and pH 7.0.

The equilibrium constant for the hydrolysis of the peptide alanylglycine (Gly-Ala in the reaction from Part B) by a peptidase is K = 9.0 × 10² at 310 K. Calculate AG for this reaction. Express the Gibbs free energy to three significant figures. AG = Submit ΠΑΠΙ ΑΣΦ Request Answer ? kJ/mol Keq [Gly] [Ala] [Gly-Ala]

23. An important step in glycolysis is the formation of ATP and pyruvate from phosphoenol-pyruvate (PEP) and ADP. PEP ADP pyruvate+ATP The equilibrium constant (Keq) for this reaction is approximately 2.5x10°. Calculate standard free energy change (AG°') for this reaction. Show your work. onege b. Is the reaction exergonic or endergonic at standard conditions? If, at equilibrium, the concentrations of ADP and ATP are 0.2 mM and 2.0 mM, respectively, what is the equilibrium concentration ratio of [pyruvate] to [PEP]? Show your work. с.

ver is given. A +B C+ D 1) Calculate AG for the above react un and indicáte whether the reaction is favorable or unfavorable [A] = 0.9 M 20°C AG° = 4 KJ/mol %3D [B] = 15mM [C] = 4mM [D] = 3 M R= 8.314 J/moleK %3D %3D 4.7 and explain how you know.

Calculate AG for this reaction under the following conditions: 37°C, pH 7, [Pyruvate] = [CO₂] = 4.0 mM, [OAA] = 2.0 mM, [ATP] = 3.5 mM, [P;] = 5.0 mM, and [ADP] = 1.8 mM. Use 2 signficant figures. AG= i kJ.mol-1 Under these conditions, the reaction is (Tolerance is +/- 2%)

6. The AG of the citric acid cycle reaction catalyzed by succinyl-CoA synthetase is approximately 0 kJ/mol. Which of the following statements explains why we would expect this reaction to be highly exergonic, but why the overall AG = 0 in reality. A) The reaction cleaves a thioether linkage, and the released free energy is used to generate a new thioester linkage in a product molecule. B) The reaction cleaves a thioester linkage, and the released free energy is used to generate GTP. C) The reaction cleaves a thioester linkage, and the released free energy is used to generate a new thioester linkage in a product molecule. D) None of the above

7. Representative values of Vm and ApH for the inner mitochondrial membrane and the thylakoid membrane at 25°C are provided in the table. Vm Арн 1.0 pmf Inner mitochondrial 0.166 V 0.2251 membrane Thylakoid membrane O,1483 0.03 V B) What is the value of AG for the thermodynamically feasible (“downhill") movement of 1 mole of H across the inner mitochondrial membrane?

3. Respiration is related to how cells balance redox reactions in the metabolic pathway. It can be aerobic if there is plenty of oxygen present or anaerobic if not. In class, we discussed the respiratory quotient for triolein as a carbon source. A. Calculate the respiratory quotient (RQ) for aerobic oxidation of the triglyceride formed by glycerin and three stearic acids (tristearin). Draw the structure and write the stoichiometrically balanced equation for the complete breakdown of the triglyceride by oxidation to CO₂ and water. B. As in part A, draw the structure of sucrose, write the stoichiometrically balanced equation and determine the RQ for it's metabolic breakdown to CO₂ and water. C. Anaerobic respiration occurs when cells operate without dissolved oxygen. List at least 4 different chemicals that act as electron acceptors when oxygen is not present.