1966, Ferdinand showed that a random-order ternary-complex mechanism for a two-substrate enzyme-catalysed reaction can lead to sigmoidal kinetics being observation in the absence of cooperative binding. Discuss this scenario so that it is clear why a plot of Vo versus [AXo] at constant [Bo] will be sig

1966, Ferdinand showed that a random-order ternary-complex mechanism for a two-substrate enzyme-catalysed reaction can lead to sigmoidal kinetics being observation in the absence of cooperative binding. Discuss this scenario so that it is clear why a plot of Vo versus [AXo] at constant [Bo] will be sig

Biochemistry

6th Edition

ISBN:9781305577206

Author:Reginald H. Garrett, Charles M. Grisham

Publisher:Reginald H. Garrett, Charles M. Grisham

Chapter23: Fatty Acid Catabolism

Section: Chapter Questions

Problem 21P: Using the ActiveModel for enoyl-CoA dehydratase, give an example of a case in which conserved...

See similar textbooks

Similar questions

Using the ActiveModel for aldose reductase, describe the structure of the TIM barrel motif and the structure and location of the active site.
Using the ActiveModel for enoyl-CoA dehydratase, give an example of a case in which conserved residues in slightly different positions can change the catalytic rate of reaction.
In 1966, Ferdinand showed that a random-order ternary-complex mechanism for a two-substrate enzyme-catalysed reaction can lead to sigmoidal kinetics being observation in the absence of cooperative binding. Discuss this scenario so that it is clear why a plot of Vo versus [AXo] at constant [Bo] will be sigmoidal.
1967, Rabin demonstrated that a single substrate reaction catalised by an enzyme that has a single binding site for the substrate, can show sigmoidal kinetics. Discuss this scenario so that it is clear why a plot of Vo versus [SJ at fixed total enzyme concentration will be sigmoidal.
Explain and differentiate the lock-and-key and induced fit models for binding of a substrate to an enzyme. If only a few of the amino acid residues of an enzyme are involved in its catalytic activity, then why does the enzyme need such a large number of amino acids?
The accompanying figure shows three Lineweaver–Burk plots for enzymereactions that have been carried out in the presence, or absence, of aninhibitor. Indicate what type of inhibition is predicted based on eachLineweaver–Burk plot. For each plot indicate which line corresponds to thereaction without inhibitor and which line corresponds to the reaction withinhibitor present.
Compare and contrast Bound Fraction equation in ligand binding and Michaelis-Menten equation in enzyme kinetics, including their double-reciprocal forms. Discuss what Km is important for and what Vmax (or kcat) is important for? Under what (substrate) conditions is Km more important than Vmax, and under what (substrate) conditions is Vmax more important than Km? Based on the discussions in question 2, explain what type of inhibitors works best under (a) high substrate concentration and (b) low substrate concentration.
Many enzyme -catalyzed reactions are consistent with a modified version of the Michaelis -Menten mechanism in which the second step is also reversible. For this mechanism obtain an expression for the rate of formation of product and find its limiting behavior for large and small concentrations of substrate using steady state approximation
Explain why each of the following data sets from a Lineweaver–Burk plot are not individually ideal for determining KM for an enzymecatalyzed reaction that follows Michaelis–Menten kinetics.
Although graphical methods are available for accurate determination of the Vmax and Km of an enzyme-catalyzed reaction, sometimes these quantities can be quickly estimated by inspecting values of V0 at increasing [S]. Estimate the Vmax and Km of the enzyme-catalyzed reaction for which the following data were obtained:
Using the appropriate graph and table above, explain what the N426S mutation appears to be doing to the enzyme’s function. Discuss the kinetic parameter changes and their meaning in this context, not the structure of the enzyme, which was not given to you.
When enzyme solutions are heated, there is a progressive loss of catalytic activity over time due to denaturation of the enzyme. A solution of the enzyme hexokinase incubated at 45 °C lost 50% of its activity in 12 min, but when incubated at 45 °C in the presence of a very large concentration of one of its substrates, it lost only 3% of its activity in 12 min. Suggest why thermal denaturation of hexokinase was retarded in the presence of one of its substrates.