A research group discovers a neW version oI happyasee, which they nappyase", that catalyzes the chemical reaction HAPPY = SAD The researchers begin to characterize the enzyme. In the first experiment, with [E] at 4 nM, they find that the Vmax is 1.6 µM s-1. Based on this experiment, what is the kcat for happyase*? kcat 400 S In another experiment, with [E,] at 1 nM and [HAPPY] at 30 µM, the researchers find that Vo is equal to 300 nM s-1. What i the measured Km of happyase* for its substrate HAPPY? Km 10 x10–6 Incorrect Further research shows that the purified happyase* used in the first two experiments was actually contaminated with a reversible inhibitor called ANGER. When ANGER is carefully removed from the happyase* preparation, and the two experiments repeated, the measured Vmax increases to 4.8 µM s-, and the measured Km is now 15 µM. S For the inhibitor ANGER, calculate the values of a' and a. a' 2 Incorrect 2

A research group discovers a neW version oI happyasee, which they nappyase", that catalyzes the chemical reaction HAPPY = SAD The researchers begin to characterize the enzyme. In the first experiment, with [E] at 4 nM, they find that the Vmax is 1.6 µM s-1. Based on this experiment, what is the kcat for happyase? kcat 400 S In another experiment, with [E,] at 1 nM and [HAPPY] at 30 µM, the researchers find that Vo is equal to 300 nM s-1. What i the measured Km of happyase for its substrate HAPPY? Km 10 x10–6 Incorrect Further research shows that the purified happyase* used in the first two experiments was actually contaminated with a reversible inhibitor called ANGER. When ANGER is carefully removed from the happyase* preparation, and the two experiments repeated, the measured Vmax increases to 4.8 µM s-, and the measured Km is now 15 µM. S For the inhibitor ANGER, calculate the values of a' and a. a' 2 Incorrect 2

Chemistry & Chemical Reactivity

10th Edition

ISBN:9781337399074

Author:John C. Kotz, Paul M. Treichel, John Townsend, David Treichel

Publisher:John C. Kotz, Paul M. Treichel, John Townsend, David Treichel

Chapter14: Chemical Kinetics: The Rates Of Chemical Reactions

Section14.7: Reaction Mechanisms

Problem 1.2ACP

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A research group discovers a new version of happyase, which they call happyase*, that catalyzes the chemical reaction HAPPY ⇌ SAD. The researchers begin to characterize the enzyme. (a) In the first experiment, with [Et] at 4 nM, they find that the Vmax is 1.6 μM s−1. Based on this experiment, what is the kcat for happyase*? (Include appropriate units.) (b) In another experiment, with [Et] at 1 nM and [HAPPY] at 30 μM, the researchers find that V0 = 300 nM s−1. What is the measured Km of happyase* for its substrate HAPPY? (Include appropriate units.) (c) Further research shows that the purified happyase used in the first two experiments was actually contaminated with a reversible inhibitor called ANGER. When ANGER is carefully removed from the happyase preparation and the two experiments repeated, the measured Vmax in (a) is increased to 4.8 μM s−1, and the measured Km in (b) is now 15 μM. For the inhibitor ANGER, calculate the values of α and α′. . (d) Based on the information given…
A research group discovers a new version of happyase, which they call happyase*, that catalyzes the chemical reaction The researchers begin to characterize the enzyme. a)In the first experiment, with [Et] at 4 nM, they find that the Vmax is 1.6 μM s-1. Based on this experiment, what is the kcat for happyase*? (Include appropriate units.) b)In another experiment, with [Et] at 1 nM and [HAPPY] at 30 μM, the researchers find that V0300 nM s-1. What is the measured Km of happyase* for its substrate HAPPY? (Include appropriate units.) c)Further research shows that the purified happyase* used in the first two experiments wasactually contaminated with a reversible inhibitor called ANGER. When ANGER is carefully removed from the happyase* preparation, and the two experiments repeated, the measured Vmax in (a) is increased to 4.8 μM s-1, and the measured Km in (b) is now 15 μM. For the inhibitor ANGER, calculate the values of αand α’.
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