Eadie plots

Equation 7.3.31 gives rise to what is known as an Eadie or Hofstee plot, while equation 7.3.32 gives rise to a Hanes plot. The Eadie plot has the advantage of spreading the points out more evenly and of determining K and J ax separately. The three types of plots are shown schematically in Figure 7.4. The Lineweaver-Burk and Eadie plots are the ones used most frequently in data analysis. 

The Eadie plot does not compress the higher values, but the values of v against [S] are more difficult to determine rapidly from it. The Eadie plot is considered more accurate and generally superior.7,8... 

Equation 6.23 is in the same form as the Michaelis-Menten equation, and may be manipulated in the same way. A good strategy in plotting the data is to use the equivalent of the Eadie plot ... 

Czarniecki also has examined another cinnamic acid derivative (12), in an attempt to explore the relevance of our ideas about binding geometry. Since the f-butylphenyl group binds to j3-cyclodextrin in these mixed solvents about as well as a ferrocene nucleus does (4), Czarniecki examined substrate III, the p-nitrophenyl ester of cinnamic acid carrying a ra-t-butyl group. The methoxyl group is present on the substrate for synthetic simplicity. This substrate binds nicely to /3-cyclodextrin in our medium, and again an Eadie plot shows that a one-to-one complex is formed. However, the acceleration in this case is only 1200-fold compared with hydrolysis of the substrate by the same buffer, so this is approximately 600 times less effective as a sub-... 

Figure 14. Lineweaver-Burk plot and Eadie plot (inset) of the oxidation of la-DOFA by mushroom tyrosinase...

Michaelis-Menten saturation kinetics should occur only at low substrate concentrations, near 10 M. Using a spectrophotometric assay it is possible to observe statistically significant deviations as shown by the Line-weaver-Burke and Eadie plots in Figure 14 using DOPA as the substrate in the catecholase reaction. 

Example CD7-4 Derive a Rate Law For Non-Competitive Inhibition Example CD7-5 Match Eadie Plots to the Different Types of Inhibition... 

Because of the limitation of double-reciprocal plots described above, other linear plotting forms have been devised. One of these, the Eadie plot, graphs V versus V/[S]. Another, the Elanes-Woolf plot, ([S]/V versus [S]) is perhaps the most useful in minimizing the difficulties of the double-reciprocal plot. 

Use these data to prepare both Lineweaver-Burk and Eadie plots and determine the Michaehs-Menten parameters associated with each type of plot. Comment. 

An alternative linear plot is the Eadie plot," for which Eq. (13.1-45) is put into the form... 

Figure 14.3 (a) Lineweaver-Burk plot, (b) Eadie plot. 

Eadie plots represent v/[S] as a function of the reaction rate itself. The plot is also linear for a Michaelis-Menten mechanism, but the slope in l/K and the intercept at the origin is V JK, as illustrated in Figure 14.3. Although, where the quality of the experimental data permits, with the development of efficient computer software packages, the Eadie, Lineweaver-Burk and related treatments should be considered as starling points for more sophisticated treatments of data within the Michaelis-Menten scheme, these simple plots are still widely used. 

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