A certain enzyme, which is only found in unicorns, catalyzes the synthesis of a growth regulator that affects the properties of unicorn horns. The activity of this enzyme is dependent on the protonation state of two ionizable groups that are present in the active site: the enzyme's N-terminal amino group and an aspartate residue. Based on biochemical studies, the role of aspartate (pk4) appears to be to stabilize a positive charge of a key reaction intermediate, while the N-terminal amino group (pk, = 6.4) acts as a general acid. The active site is located in a hydrophobic pocket. %3D Construct a semi-quantitative graph (x-axis = pH and y-axis = % activity) in which you plot how the activity of this enzyme varies with pH. [HINT: Be sure to clearly plot several well-chosen points on your graph so the form of the graph is reasonable. Minimally, you must plot points for when each ionizable group is 10%, 50% and 90% ionized. Each of these points can be readily determined from the Henderson-Hasselbach equation.) %3D %3D

A certain enzyme, which is only found in unicorns, catalyzes the synthesis of a growth regulator that affects the properties of unicorn horns. The activity of this enzyme is dependent on the protonation state of two ionizable groups that are present in the active site: the enzyme's N-terminal amino group and an aspartate residue. Based on biochemical studies, the role of aspartate (pk4) appears to be to stabilize a positive charge of a key reaction intermediate, while the N-terminal amino group (pk, = 6.4) acts as a general acid. The active site is located in a hydrophobic pocket. %3D Construct a semi-quantitative graph (x-axis = pH and y-axis = % activity) in which you plot how the activity of this enzyme varies with pH. [HINT: Be sure to clearly plot several well-chosen points on your graph so the form of the graph is reasonable. Minimally, you must plot points for when each ionizable group is 10%, 50% and 90% ionized. Each of these points can be readily determined from the Henderson-Hasselbach equation.) %3D %3D

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Description: 4. A certain enzyme, which is only found in unicorns, catalyzes the synthesis of a growth regulator that affectsthe properties of unicorn horns. The activity of this enzyme is dependent on the protonation state of twoionizable groups that are presen

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

Chapter4: Cells

Section: Chapter Questions

Problem 1ITD

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1. The diagram to the right illustrates in panel A the N- acetyl-glutamate content of rat livers as a function of time after intraperitoneal injection of a load of amino acids containing glutamate (1.5 g/kg body weight). The lower panel B illustrates the activity of carbamoyl phosphate synthetase I activity isolated from intact rat liver mitochondria similarly as a function of time after intraperitoneal injection of a load of amino acids (1.5 g/kg body weight). Virtually identical data were generated when only L- glutamate was injected intraperitoneally instead of the load of amino acids containing glutamate. It was also shown that the liver content of endogenous arginine and ornithine remained constant when arginine was omitted from the amino acid mixture. (a) (b) (c) (d) Write the reactions using structural formulas underlying the observations in the two diagrams to the right (one for each panel). Include all the reactants, enzymes and cofactors. Make sure the chiral centers are…
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