Many enzymes obey simple Michaelis–Mentenkinetics, which are summarized by the equationrate = Vmax [S]/([S] + Km)where Vmax = maximum velocity, [S] = concentration ofsubstrate, and Km = the Michaelis constant.It is instructive to plug a few values of [S] into theequation to see how rate is affected. What are the rates for[S] equal to zero, equal to Km, and equal to infinite concen-tration?

Many enzymes obey simple Michaelis–Mentenkinetics, which are summarized by the equationrate = Vmax [S]/([S] + Km)where Vmax = maximum velocity, [S] = concentration ofsubstrate, and Km = the Michaelis constant.It is instructive to plug a few values of [S] into theequation to see how rate is affected. What are the rates for[S] equal to zero, equal to Km, and equal to infinite concen-tration?

Biochemistry

6th Edition

ISBN:9781305577206

Author:Reginald H. Garrett, Charles M. Grisham

Publisher:Reginald H. Garrett, Charles M. Grisham

Chapter18: Glycolysis

Section: Chapter Questions

Problem 17P

See similar textbooks

Similar questions

Using the Nernst equation, calculate the equilibrium potential for Ca2 and for C1 from the following sets of data: a. Given [ Ca2+ ]0=1mM,[ Ca2+ ]i=100nM, find Eca2+ b. Given [ Cl- ]0=110mM,[ Cl- ]i=100mM, find Ecl
For a Michaelis-Menten enzyme, k1 = 5.2 ⅹ 108 M-1 s -1 , k-1 = 3.1 ⅹ 104 s -1 , and k2 = 3.4 ⅹ 105 s -1 . a) Write out the reaction, showing k1, k-1, and k2. Calculate Ks and Km. Does substrate binding approach rapid equilibrium or the steady state? Show work justify b) What is kcat for this reaction? Show work justify c) Calculate Vmax for the enzyme. The total enzyme concentration is 25 pmol L-1 , and each enzyme has two active sites.
If instead of using 3.5 µM myoglobin (receptor) you used half of this (that is, 1.75 µM myoglobin), what would be that value of the Kd, that you calculated ( how would it change)? Please explain so I can solve on my own :) (How does changing concentration of the receptor in a ligand-receptor binding experiment affect the dissociation constant?)
Neutral sphingomyelinase 2 converts sphingomyelin into ceramide and phosphorcholine. What kind of enzyme is it? Assume Vmax is 35 µM min-1. When you provide 3.0 x 10-5 M of sphingomyelin, you observe an initial velocity of 6.0 µM min-1. Calculate the KM.
An enzyme that follows simple Michaelis–Menten kinetics has an initial reaction velocity of 10 µmol⋅min-1 when the substrate concentration is five times greater than the KM. What is the Vmax of this enzyme in µmol⋅min−1?
The turnover number for an enzyme that approximates Michaelis-Menten kinetics is known to be 500 min^-1. From the results shown in the table, enumerate Km and total amount of enzyme present. What is the Km for this enzyme? What is the Vmax for this enzyme? And what is the [E]T for this enzyme?
For an enzyme that displays Michaelis-Menton kinetics, what is thereaction velocity, V (as a percentage of V max , observed at the followingvalues?[S] = K M[S] = 0.5K M[S] = 0.1K M[S] = 2K M[S] = 10K M
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:
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.
In a rat cardiomyocyte, the levels of creatine, phosphocreatine, and free phosphate were found to be 37.6mM, 40.3mM, and 8.02mM, respectively. Given that the standard free energy change is –43.0 kJ/mol, what is the true free energy change for phosphocreatine hydrolysis in the cardiomyocyte described above?
Give an example of a noncompetitive inhibitor and its target enzyme. Draw a hypothetical Michaelis-Menten curves in the presence and absence of the noncompetitive inhibitor. Discuss the effects of noncompetitive inhibition and the reasons for these effects on the values of Km and Vmax.
Q is an analog of substrate A that binds to enzyme X and produces the following kinetics:[A] V0 (µmole/ml/min) [Q] = 0 [Q] = 0.5 µM [Q] = 2 µM1 µM 10 7 43 µM 20 16 1010 µM 35 31 2330 µM 43 41 3680 µM 47 46 43a) Plot the data in Lineweaver Burk plot form (Hint: there should be three plots of dataon your graph) and determine the following: the KM and Vmax of the enzyme X in theabsence of Q, and the KMapp the Vmaxapp at each concentration of Q. b) What type of inhibition is this?c) Calculate the inhibition constant (Ki) for Compound Q