Given the Km and Vmax values of three enzymes, A, B and C: Enzyme Km Vmax A 2.0 x 103 M 4.0 B 4.2 x 104M 1.8 C 1.0 x 10-3 M 2.5 Which enzyme would have the highest activity? Why?

A particular reaction has a ΔG‡ of 37.0 kJ mol-1. In the presence of an enzyme, the same reaction has a ΔG‡ of 5.70 kJ mol-1. Calculate the value of ΔΔG‡ in kJ mol-1.

The kinetic data of an enzymatic reaction shown in the following table: a. Calculate the Km and Vmax of the reactionb. A competitive inhibitor is added to the reaction at a concentration of 5 μM, determine the new Vmax of the reaction and what happened to the Km value.

The enzyme triosephosphate isomerase (TIM) catalyzes the following reaction in glycolysis, where it converts dihydroxyacetone phosphate (DHAP) to glyceraldehyde-3-phosphate (GAP). CH₂OH C=O CH₂OPO²- DHAP triose phosphate isomerase [DHAP] (MM 1.00 2.00 3.00 6.00 O V. (mM/s) 3.700 6.727 9.250 14.800 = H HCOH CH₂OPO²- Kinetics experiments were performed on TIM. Enzyme activity (initial velocity, V.) was measured at varying concentrations of DHAP. The enzyme kinetics were also measured in the presence of two inhibitors, A and B. The enzyme concentration used in all experiments was 25.00 μM. The data are shown below. GAP V. (mM/s) + A 1.452 2.794 4.038 7.281 V₁ (mM/s) + B 0.755 1.379 1.905 3.077

(b) You are investigating the effects of several agents on the activity of alcohol dehydrogenase. The enzyme activity data are shown in the table below. Construct a [substrate] vs. activity plot and a double-reciprocal plot for this enzyme. Be sure to label all axes. Determine the Vmax and KM for AD from the graphs in each type of plot. AD activity (nM/min) AD activity + agent A (nM/min) AD activity + agent B (nM/min) [Alcohol] (nM) 0.1 14 2 0.5 50 7 8. 1.0 65 10 30 2.0 72 12 45 4.0 80 14 62 8.0 85 15 75 32.0 90 16 90

An enzyme catalyzes a reaction with a Km of 7.50 mM and a Vmax of 2.90 mM - s-1. Calculate the reaction velocity, un, for each substrate concentration. [S] = 2.75 mM mM · s- * TOOLS x10 [S] = 7.50 mM mM · s-! [S] = 11.0 mM mM - s-

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.

Consider the Michaelis-Menten enzymes below and answer the following questions. Kcat (s') 9.5*105 1.4*10* 2.5*102 1.0*107 5.0*10 8.0*10² Enzyme Km (M) A В a. Which enzyme has the highest affinity substrate? How do you know? b. Which enzyme can convert the most substrate to product in a given period of time? How do you know? c. Which enzyme has the highest catalytic efficiency? How do you know?

How many net molecules of nucleoside triphosphate (ATP and equivalent molecules) are produced by complete aerobic catabolism of a glucose going through glycolysis, the pyruvate dehydrogenase complex and the citric acid cycle (TCA cycle)? Do not count the ATP eventually generated by re-oxidation of reduced coenzymes, just the number of NTPs produced in reactions of these pathways. Choose the one best answer. 02 03 04 05 06 8

Below is kinetic data obtained for an enzyme-catalyzed reaction. The enzyme concentration is fixed at 100 nM. Using a Lineweaver-Burke plot, calculate the catalytic efficiency for this reaction. Report your answer in scientific notation to three significant figures in units of M-1s-1.