1.) The protein SIRT6 has been shown to be important in energy metabolism and inflammatory responses. The authors of a recent paper indicate that increasing expression and activity of SIRT6 may be beneficial in neurodegenerative diseases, diabetes and arthritis. The protein has deacetylase activity. The authors watched the disappearance of a nitro-fatty acid as a function of time in a reaction catalyzed by human Sirt6 as below. J. Biol. Chem. jbc.RA120.014883. doi:10.1074/jbc.RA120.014883 B Absorbance 330 nm 0.08 0.06 0.04 0.02- 0.00 0 2 4 ■ 6 8 10 12 14 16 t (min) a) How is the absorbance related to the fraction (0) of the reactant remaining? b) Is there evidence that the reaction is first order in this reactant concentration?

1.) The protein SIRT6 has been shown to be important in energy metabolism and inflammatory responses. The authors of a recent paper indicate that increasing expression and activity of SIRT6 may be beneficial in neurodegenerative diseases, diabetes and arthritis. The protein has deacetylase activity. The authors watched the disappearance of a nitro-fatty acid as a function of time in a reaction catalyzed by human Sirt6 as below. J. Biol. Chem. jbc.RA120.014883. doi:10.1074/jbc.RA120.014883 B Absorbance 330 nm 0.08 0.06 0.04 0.02- 0.00 0 2 4 ■ 6 8 10 12 14 16 t (min) a) How is the absorbance related to the fraction (0) of the reactant remaining? b) Is there evidence that the reaction is first order in this reactant concentration?

Biochemistry

9th Edition

ISBN:9781319114671

Author:Lubert Stryer, Jeremy M. Berg, John L. Tymoczko, Gregory J. Gatto Jr.

Publisher:Lubert Stryer, Jeremy M. Berg, John L. Tymoczko, Gregory J. Gatto Jr.

Chapter1: Biochemistry: An Evolving Science

Section: Chapter Questions

Problem 1P

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Human xanthine oxidase catalyzes the oxidation of hypoxanthine to xanthine and can furthercatalyze the oxidation of xanthine to uric acid. For the treatment of hyperuricemia and gout,several medications are used to inhibit the activity of xanthine oxidase and reduce theproduction of uric acid. You are a biochemist and just discovered a chemical that can inhibitthe activity of the human xanthine oxidase. When analyzing its mode of inhibition, you foundthat the enzyme inhibitor complex requires 450 kJ.mol-1 to dissociate and that it displayskinetics somehow similar to noncompetitive inhibition. You sent your inhibitor to the ministryof health for approval as a medication for gout. Based on the data provided, are they going toauthorize it as a medication or not? Explain? Please be aware that energy is 450 kJ.mol-1, not 450 J.mol-1
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Describe two reasons why the reaction glutamine synthetase performs is important to the body.
Human xanthine oxidase catalyzes the oxidation of hypoxanthine to xanthine and can furthercatalyze the oxidation of xanthine to uric acid. For the treatment of hyperuricemia and gout,several medications are used to inhibit the activity of xanthine oxidase and reduce theproduction of uric acid. You are a biochemist and just discovered a chemical that can inhibitthe activity of the human xanthine oxidase. When analyzing its mode of inhibition, you foundthat the enzyme inhibitor complex requires 450 kJ.mol-1 to dissociate and that it displayskinetics somehow similar to noncompetitive inhibition. You sent your inhibitor to the ministryof health for approval as a medication for gout. Based on the data provided, are they going toauthorize it as a medication or not? Explain? (notice that its 450 kj not j)
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