14. The steady-state kinetics of an enzyme are studied in the absence and pres- ence of an inhibitor (inhibitor A). The initial rate is given as a function of substrate concentration in the following table: v[(mmol/L)min ] [S] (mmol/L) No inhibitor Inhibitor A 1.25 1.72 0.98 1.67 2.04 1.17 2.50 2.63 1.47 5.00 3.33 1.96 10.00 4.17 2.38 (a) What kind of inhibition (competitive, uncompetitive, or mixed) is involved? (b) Determine Vmar and K in the absence and presence of inhibitor. 15. The same enzyme as in Problem 14 is studied in the presence of a different inhibitor (inhibitor B). In this case, two different concentrations of inhibitor are used. Data are as follows: v[(mmol/L)min-] [S] (mmol/L) No inhibitor 3 mM inhibitor B 5 mM inhibitor B 1.25 1.72 1.25 1.01 1.67 2.04 1.54 1.26 2.50 2.63 2.00 1.72 5.00 3.33 2.86 2.56 10.00 4.17 3.70 3.49 (a) What kind of inhibitor is inhibitor B? (b) Determine the apparent Vmax and KM at each inhibitor concentration. (c) Estimate K from these data.

14. The steady-state kinetics of an enzyme are studied in the absence and pres- ence of an inhibitor (inhibitor A). The initial rate is given as a function of substrate concentration in the following table: v[(mmol/L)min ] [S] (mmol/L) No inhibitor Inhibitor A 1.25 1.72 0.98 1.67 2.04 1.17 2.50 2.63 1.47 5.00 3.33 1.96 10.00 4.17 2.38 (a) What kind of inhibition (competitive, uncompetitive, or mixed) is involved? (b) Determine Vmar and K in the absence and presence of inhibitor. 15. The same enzyme as in Problem 14 is studied in the presence of a different inhibitor (inhibitor B). In this case, two different concentrations of inhibitor are used. Data are as follows: v[(mmol/L)min-] [S] (mmol/L) No inhibitor 3 mM inhibitor B 5 mM inhibitor B 1.25 1.72 1.25 1.01 1.67 2.04 1.54 1.26 2.50 2.63 2.00 1.72 5.00 3.33 2.86 2.56 10.00 4.17 3.70 3.49 (a) What kind of inhibitor is inhibitor B? (b) Determine the apparent Vmax and KM at each inhibitor concentration. (c) Estimate K from these data.

Biology: The Dynamic Science (MindTap Course List)

4th Edition

ISBN:9781305389892

Author:Peter J. Russell, Paul E. Hertz, Beverly McMillan

Publisher:Peter J. Russell, Paul E. Hertz, Beverly McMillan

Chapter6: Energy, Enzymes, And Biological Reactions

Section: Chapter Questions

Problem 9TYK: Which of the following statements about inhibition is true? a. Allosteric inhibitors and allosteric...

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