Its 3. Aspartate transcarbamoylase (ATCase) catalyzes the reaction: carbamoylphosphate + aspartate carbamoylaspartate and phosphate. The charge of carbamoylaspartate is activity is allosterically regulated by CTP and ATP. ATCase has six catalytic subunits and six regulatory subunits. CTP is an allosteric inhibitor and also a possible inhibitor. a) -1; noncompetitive b)-1; uncompetitive c) -2; noncompetitive d) -2; uncompetitive

Its 3. Aspartate transcarbamoylase (ATCase) catalyzes the reaction: carbamoylphosphate + aspartate carbamoylaspartate and phosphate. The charge of carbamoylaspartate is activity is allosterically regulated by CTP and ATP. ATCase has six catalytic subunits and six regulatory subunits. CTP is an allosteric inhibitor and also a possible inhibitor. a) -1; noncompetitive b)-1; uncompetitive c) -2; noncompetitive d) -2; uncompetitive

Biochemistry

6th Edition

ISBN:9781305577206

Author:Reginald H. Garrett, Charles M. Grisham

Publisher:Reginald H. Garrett, Charles M. Grisham

Chapter27: Metabolic Integration And Organ Specialization

Section: Chapter Questions

Problem 20P: Figure 27.3 illustrates the response of R (ATP-regenerating) and U (ATP-utilizing) enzymes to energy...

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The enzyme mutase which is important for the synthetic of tyrosine and phenylalanine in saccharomyces cerevisiae has been studied as an example of an allosteric enzyme. Tyrosine acts as a negative effector for this enzyme. What effects would you see on the action of the enzyme were you to increase the concentration of tyrosine? The chorismate mutase would shift to its R conformation The curve showing the kinetics or chorismate mutase would shift to the right The curve showing the kinetics of chorismate mutase would shift to the left The chorismate mutase would become saturated more rapidly
Trypsin uses a nearly identical mechanism as chymotrypsin (including the catalytic triad his57-ser195-asp102. beginning with the enzyme substrate complex draw the complete steps in the trypsin mechanism that occur to release the first product and create the acyl enzyme intermediate in the trypsin active site. The substrate for trypsin to be used is gly-lys-gly-ala
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UDP-glucose pyrophosphorylase catalyzes the removal of a pyrophosphate group from UTP as it synthesizes UDP-glucose. Why is this necessary, from a biochemical perspective? Both of the phosphate groups from UTP are needed to form UDP-glucose. There is no particular reason: wasteful reactions just happen sometimes. The pyrophosphate (after hydrolysis) is required to free up more phosphate for the synthesis of ATP by oxidative phosphorylation. The subsequent hydrolysis of pyrophosphate is a highly exergonic reaction, which pulls the equilibrium over towards UDP-glucose. Pyrophosphate is an allosteric activator of glycogen synthase, so this helps glycogen synthesis to proceed at a faster rate.
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The KMof the enzyme for the substrate adenosine is 3 × 10ꟷ5M. The product inosine acts as an inhibitor of the reaction, with an inhibition constant (KI, the dissociation constant for enzyme-inhibitor binding) of 3 × 10ꟷ4M. However, a transition state analog,Inhibits the reaction with KIof 1.5 × 10ꟷ13M. Explain why 1,6-dihydroinosine serves as a better inhibitor of adenosine deaminase than inosine. Elaborate on your answe
Aspartate transcarbamoylase, which is necessary for CTP production, is an essential enzyme for the human body. In the below graph, which line represents the rate of the reaction catalyzes by Aspartate transcarbamoylase? Explain.
Because it resembles the two physiological substrates, phosphonacetyl L - aspartate (PALA) is a strong inhibitor of ATCase. Low concentrations of this unreactive bisubstrate analog, on the other hand, enhance reaction velocity in the presence of substrates. The reaction rate rises as PALA is added, until three molecules of PALA are attached per molecule of enzyme. This maximum velocity is 17 times higher than it would be without PALA. With the addition of three additional molecules of PALA per molecule of enzyme, the reaction rate drops to practically nil. Why does PALA activate ATCase at such low concentrations?
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